1 /*
2 ** 2001-09-15
3 **
4 ** The author disclaims copyright to this source code.  In place of
5 ** a legal notice, here is a blessing:
6 **
7 **    May you do good and not evil.
8 **    May you find forgiveness for yourself and forgive others.
9 **    May you share freely, never taking more than you give.
10 **
11 *************************************************************************
12 ** This header file defines the interface that the SQLite library
13 ** presents to client programs.  If a C-function, structure, datatype,
14 ** or constant definition does not appear in this file, then it is
15 ** not a published API of SQLite, is subject to change without
16 ** notice, and should not be referenced by programs that use SQLite.
17 **
18 ** Some of the definitions that are in this file are marked as
19 ** "experimental".  Experimental interfaces are normally new
20 ** features recently added to SQLite.  We do not anticipate changes
21 ** to experimental interfaces but reserve the right to make minor changes
22 ** if experience from use "in the wild" suggest such changes are prudent.
23 **
24 ** The official C-language API documentation for SQLite is derived
25 ** from comments in this file.  This file is the authoritative source
26 ** on how SQLite interfaces are supposed to operate.
27 **
28 ** The name of this file under configuration management is "sqlite.h.in".
29 ** The makefile makes some minor changes to this file (such as inserting
30 ** the version number) and changes its name to "sqlite3.h" as
31 ** part of the build process.
32 */
33 
34 module d2sqlite3.sqlite3;
35 
36 import core.stdc.stdarg;
37 
38 extern (C):
39 nothrow:
40 @nogc:
41 
42 /* Needed for the definition of va_list */
43 
44 /*
45 ** Make sure we can call this stuff from C++.
46 */
47 
48 /*
49 ** Provide the ability to override linkage features of the interface.
50 */
51 
52 /*
53 ** These no-op macros are used in front of interfaces to mark those
54 ** interfaces as either deprecated or experimental.  New applications
55 ** should not use deprecated interfaces - they are supported for backwards
56 ** compatibility only.  Application writers should be aware that
57 ** experimental interfaces are subject to change in point releases.
58 **
59 ** These macros used to resolve to various kinds of compiler magic that
60 ** would generate warning messages when they were used.  But that
61 ** compiler magic ended up generating such a flurry of bug reports
62 ** that we have taken it all out and gone back to using simple
63 ** noop macros.
64 */
65 
66 /*
67 ** Ensure these symbols were not defined by some previous header file.
68 */
69 
70 /*
71 ** CAPI3REF: Compile-Time Library Version Numbers
72 **
73 ** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
74 ** evaluates to a string literal that is the SQLite version in the
75 ** format "X.Y.Z" where X is the major version number (always 3 for
76 ** SQLite3) and Y is the minor version number and Z is the release number.)^
77 ** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
78 ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
79 ** numbers used in [SQLITE_VERSION].)^
80 ** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
81 ** be larger than the release from which it is derived.  Either Y will
82 ** be held constant and Z will be incremented or else Y will be incremented
83 ** and Z will be reset to zero.
84 **
85 ** Since [version 3.6.18] ([dateof:3.6.18]),
86 ** SQLite source code has been stored in the
87 ** <a href="http://www.fossil-scm.org/">Fossil configuration management
88 ** system</a>.  ^The SQLITE_SOURCE_ID macro evaluates to
89 ** a string which identifies a particular check-in of SQLite
90 ** within its configuration management system.  ^The SQLITE_SOURCE_ID
91 ** string contains the date and time of the check-in (UTC) and a SHA1
92 ** or SHA3-256 hash of the entire source tree.  If the source code has
93 ** been edited in any way since it was last checked in, then the last
94 ** four hexadecimal digits of the hash may be modified.
95 **
96 ** See also: [sqlite3_libversion()],
97 ** [sqlite3_libversion_number()], [sqlite3_sourceid()],
98 ** [sqlite_version()] and [sqlite_source_id()].
99 */
100 enum SQLITE_VERSION = "3.21.0";
101 enum SQLITE_VERSION_NUMBER = 3021000;
102 enum SQLITE_SOURCE_ID = "2017-10-24 18:55:49 1a584e499906b5c87ec7d43d4abce641fdf017c42125b083109bc77c4de48827";
103 
104 /*
105 ** CAPI3REF: Run-Time Library Version Numbers
106 ** KEYWORDS: sqlite3_version sqlite3_sourceid
107 **
108 ** These interfaces provide the same information as the [SQLITE_VERSION],
109 ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
110 ** but are associated with the library instead of the header file.  ^(Cautious
111 ** programmers might include assert() statements in their application to
112 ** verify that values returned by these interfaces match the macros in
113 ** the header, and thus ensure that the application is
114 ** compiled with matching library and header files.
115 **
116 ** <blockquote><pre>
117 ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
118 ** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 );
119 ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
120 ** </pre></blockquote>)^
121 **
122 ** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
123 ** macro.  ^The sqlite3_libversion() function returns a pointer to the
124 ** to the sqlite3_version[] string constant.  The sqlite3_libversion()
125 ** function is provided for use in DLLs since DLL users usually do not have
126 ** direct access to string constants within the DLL.  ^The
127 ** sqlite3_libversion_number() function returns an integer equal to
128 ** [SQLITE_VERSION_NUMBER].  ^(The sqlite3_sourceid() function returns
129 ** a pointer to a string constant whose value is the same as the
130 ** [SQLITE_SOURCE_ID] C preprocessor macro.  Except if SQLite is built
131 ** using an edited copy of [the amalgamation], then the last four characters
132 ** of the hash might be different from [SQLITE_SOURCE_ID].)^
133 **
134 ** See also: [sqlite_version()] and [sqlite_source_id()].
135 */
136 extern __gshared const(char)[] sqlite3_version;
137 const(char)* sqlite3_libversion();
138 const(char)* sqlite3_sourceid();
139 int sqlite3_libversion_number();
140 
141 /*
142 ** CAPI3REF: Run-Time Library Compilation Options Diagnostics
143 **
144 ** ^The sqlite3_compileoption_used() function returns 0 or 1
145 ** indicating whether the specified option was defined at
146 ** compile time.  ^The SQLITE_ prefix may be omitted from the
147 ** option name passed to sqlite3_compileoption_used().
148 **
149 ** ^The sqlite3_compileoption_get() function allows iterating
150 ** over the list of options that were defined at compile time by
151 ** returning the N-th compile time option string.  ^If N is out of range,
152 ** sqlite3_compileoption_get() returns a NULL pointer.  ^The SQLITE_
153 ** prefix is omitted from any strings returned by
154 ** sqlite3_compileoption_get().
155 **
156 ** ^Support for the diagnostic functions sqlite3_compileoption_used()
157 ** and sqlite3_compileoption_get() may be omitted by specifying the
158 ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
159 **
160 ** See also: SQL functions [sqlite_compileoption_used()] and
161 ** [sqlite_compileoption_get()] and the [compile_options pragma].
162 */
163 
164 int sqlite3_compileoption_used(const(char)* zOptName);
165 const(char)* sqlite3_compileoption_get(int N);
166 
167 /*
168 ** CAPI3REF: Test To See If The Library Is Threadsafe
169 **
170 ** ^The sqlite3_threadsafe() function returns zero if and only if
171 ** SQLite was compiled with mutexing code omitted due to the
172 ** [SQLITE_THREADSAFE] compile-time option being set to 0.
173 **
174 ** SQLite can be compiled with or without mutexes.  When
175 ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
176 ** are enabled and SQLite is threadsafe.  When the
177 ** [SQLITE_THREADSAFE] macro is 0,
178 ** the mutexes are omitted.  Without the mutexes, it is not safe
179 ** to use SQLite concurrently from more than one thread.
180 **
181 ** Enabling mutexes incurs a measurable performance penalty.
182 ** So if speed is of utmost importance, it makes sense to disable
183 ** the mutexes.  But for maximum safety, mutexes should be enabled.
184 ** ^The default behavior is for mutexes to be enabled.
185 **
186 ** This interface can be used by an application to make sure that the
187 ** version of SQLite that it is linking against was compiled with
188 ** the desired setting of the [SQLITE_THREADSAFE] macro.
189 **
190 ** This interface only reports on the compile-time mutex setting
191 ** of the [SQLITE_THREADSAFE] flag.  If SQLite is compiled with
192 ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
193 ** can be fully or partially disabled using a call to [sqlite3_config()]
194 ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
195 ** or [SQLITE_CONFIG_SERIALIZED].  ^(The return value of the
196 ** sqlite3_threadsafe() function shows only the compile-time setting of
197 ** thread safety, not any run-time changes to that setting made by
198 ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
199 ** is unchanged by calls to sqlite3_config().)^
200 **
201 ** See the [threading mode] documentation for additional information.
202 */
203 int sqlite3_threadsafe();
204 
205 /*
206 ** CAPI3REF: Database Connection Handle
207 ** KEYWORDS: {database connection} {database connections}
208 **
209 ** Each open SQLite database is represented by a pointer to an instance of
210 ** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
211 ** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
212 ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
213 ** and [sqlite3_close_v2()] are its destructors.  There are many other
214 ** interfaces (such as
215 ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
216 ** [sqlite3_busy_timeout()] to name but three) that are methods on an
217 ** sqlite3 object.
218 */
219 struct sqlite3;
220 
221 /*
222 ** CAPI3REF: 64-Bit Integer Types
223 ** KEYWORDS: sqlite_int64 sqlite_uint64
224 **
225 ** Because there is no cross-platform way to specify 64-bit integer types
226 ** SQLite includes typedefs for 64-bit signed and unsigned integers.
227 **
228 ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
229 ** The sqlite_int64 and sqlite_uint64 types are supported for backwards
230 ** compatibility only.
231 **
232 ** ^The sqlite3_int64 and sqlite_int64 types can store integer values
233 ** between -9223372036854775808 and +9223372036854775807 inclusive.  ^The
234 ** sqlite3_uint64 and sqlite_uint64 types can store integer values
235 ** between 0 and +18446744073709551615 inclusive.
236 */
237 
238 alias sqlite_int64 = long;
239 alias sqlite_uint64 = ulong;
240 
241 alias sqlite3_int64 = long;
242 alias sqlite3_uint64 = ulong;
243 
244 /*
245 ** If compiling for a processor that lacks floating point support,
246 ** substitute integer for floating-point.
247 */
248 
249 /*
250 ** CAPI3REF: Closing A Database Connection
251 ** DESTRUCTOR: sqlite3
252 **
253 ** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
254 ** for the [sqlite3] object.
255 ** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
256 ** the [sqlite3] object is successfully destroyed and all associated
257 ** resources are deallocated.
258 **
259 ** ^If the database connection is associated with unfinalized prepared
260 ** statements or unfinished sqlite3_backup objects then sqlite3_close()
261 ** will leave the database connection open and return [SQLITE_BUSY].
262 ** ^If sqlite3_close_v2() is called with unfinalized prepared statements
263 ** and/or unfinished sqlite3_backups, then the database connection becomes
264 ** an unusable "zombie" which will automatically be deallocated when the
265 ** last prepared statement is finalized or the last sqlite3_backup is
266 ** finished.  The sqlite3_close_v2() interface is intended for use with
267 ** host languages that are garbage collected, and where the order in which
268 ** destructors are called is arbitrary.
269 **
270 ** Applications should [sqlite3_finalize | finalize] all [prepared statements],
271 ** [sqlite3_blob_close | close] all [BLOB handles], and
272 ** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
273 ** with the [sqlite3] object prior to attempting to close the object.  ^If
274 ** sqlite3_close_v2() is called on a [database connection] that still has
275 ** outstanding [prepared statements], [BLOB handles], and/or
276 ** [sqlite3_backup] objects then it returns [SQLITE_OK] and the deallocation
277 ** of resources is deferred until all [prepared statements], [BLOB handles],
278 ** and [sqlite3_backup] objects are also destroyed.
279 **
280 ** ^If an [sqlite3] object is destroyed while a transaction is open,
281 ** the transaction is automatically rolled back.
282 **
283 ** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
284 ** must be either a NULL
285 ** pointer or an [sqlite3] object pointer obtained
286 ** from [sqlite3_open()], [sqlite3_open16()], or
287 ** [sqlite3_open_v2()], and not previously closed.
288 ** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
289 ** argument is a harmless no-op.
290 */
291 int sqlite3_close(sqlite3*);
292 int sqlite3_close_v2(sqlite3*);
293 
294 /*
295 ** The type for a callback function.
296 ** This is legacy and deprecated.  It is included for historical
297 ** compatibility and is not documented.
298 */
299 alias sqlite3_callback = int function(void*, int, char**, char**);
300 
301 /*
302 ** CAPI3REF: One-Step Query Execution Interface
303 ** METHOD: sqlite3
304 **
305 ** The sqlite3_exec() interface is a convenience wrapper around
306 ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
307 ** that allows an application to run multiple statements of SQL
308 ** without having to use a lot of C code.
309 **
310 ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
311 ** semicolon-separate SQL statements passed into its 2nd argument,
312 ** in the context of the [database connection] passed in as its 1st
313 ** argument.  ^If the callback function of the 3rd argument to
314 ** sqlite3_exec() is not NULL, then it is invoked for each result row
315 ** coming out of the evaluated SQL statements.  ^The 4th argument to
316 ** sqlite3_exec() is relayed through to the 1st argument of each
317 ** callback invocation.  ^If the callback pointer to sqlite3_exec()
318 ** is NULL, then no callback is ever invoked and result rows are
319 ** ignored.
320 **
321 ** ^If an error occurs while evaluating the SQL statements passed into
322 ** sqlite3_exec(), then execution of the current statement stops and
323 ** subsequent statements are skipped.  ^If the 5th parameter to sqlite3_exec()
324 ** is not NULL then any error message is written into memory obtained
325 ** from [sqlite3_malloc()] and passed back through the 5th parameter.
326 ** To avoid memory leaks, the application should invoke [sqlite3_free()]
327 ** on error message strings returned through the 5th parameter of
328 ** sqlite3_exec() after the error message string is no longer needed.
329 ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
330 ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
331 ** NULL before returning.
332 **
333 ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
334 ** routine returns SQLITE_ABORT without invoking the callback again and
335 ** without running any subsequent SQL statements.
336 **
337 ** ^The 2nd argument to the sqlite3_exec() callback function is the
338 ** number of columns in the result.  ^The 3rd argument to the sqlite3_exec()
339 ** callback is an array of pointers to strings obtained as if from
340 ** [sqlite3_column_text()], one for each column.  ^If an element of a
341 ** result row is NULL then the corresponding string pointer for the
342 ** sqlite3_exec() callback is a NULL pointer.  ^The 4th argument to the
343 ** sqlite3_exec() callback is an array of pointers to strings where each
344 ** entry represents the name of corresponding result column as obtained
345 ** from [sqlite3_column_name()].
346 **
347 ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
348 ** to an empty string, or a pointer that contains only whitespace and/or
349 ** SQL comments, then no SQL statements are evaluated and the database
350 ** is not changed.
351 **
352 ** Restrictions:
353 **
354 ** <ul>
355 ** <li> The application must ensure that the 1st parameter to sqlite3_exec()
356 **      is a valid and open [database connection].
357 ** <li> The application must not close the [database connection] specified by
358 **      the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
359 ** <li> The application must not modify the SQL statement text passed into
360 **      the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
361 ** </ul>
362 */
363 /* An open database */
364 /* SQL to be evaluated */
365 /* Callback function */
366 /* 1st argument to callback */
367 /* Error msg written here */
368 int sqlite3_exec(
369     sqlite3*,
370     const(char)* sql,
371     int function(void*, int, char**, char**) callback,
372     void*,
373     char** errmsg);
374 
375 /*
376 ** CAPI3REF: Result Codes
377 ** KEYWORDS: {result code definitions}
378 **
379 ** Many SQLite functions return an integer result code from the set shown
380 ** here in order to indicate success or failure.
381 **
382 ** New error codes may be added in future versions of SQLite.
383 **
384 ** See also: [extended result code definitions]
385 */
386 enum SQLITE_OK = 0; /* Successful result */
387 /* beginning-of-error-codes */
388 enum SQLITE_ERROR = 1; /* Generic error */
389 enum SQLITE_INTERNAL = 2; /* Internal logic error in SQLite */
390 enum SQLITE_PERM = 3; /* Access permission denied */
391 enum SQLITE_ABORT = 4; /* Callback routine requested an abort */
392 enum SQLITE_BUSY = 5; /* The database file is locked */
393 enum SQLITE_LOCKED = 6; /* A table in the database is locked */
394 enum SQLITE_NOMEM = 7; /* A malloc() failed */
395 enum SQLITE_READONLY = 8; /* Attempt to write a readonly database */
396 enum SQLITE_INTERRUPT = 9; /* Operation terminated by sqlite3_interrupt()*/
397 enum SQLITE_IOERR = 10; /* Some kind of disk I/O error occurred */
398 enum SQLITE_CORRUPT = 11; /* The database disk image is malformed */
399 enum SQLITE_NOTFOUND = 12; /* Unknown opcode in sqlite3_file_control() */
400 enum SQLITE_FULL = 13; /* Insertion failed because database is full */
401 enum SQLITE_CANTOPEN = 14; /* Unable to open the database file */
402 enum SQLITE_PROTOCOL = 15; /* Database lock protocol error */
403 enum SQLITE_EMPTY = 16; /* Internal use only */
404 enum SQLITE_SCHEMA = 17; /* The database schema changed */
405 enum SQLITE_TOOBIG = 18; /* String or BLOB exceeds size limit */
406 enum SQLITE_CONSTRAINT = 19; /* Abort due to constraint violation */
407 enum SQLITE_MISMATCH = 20; /* Data type mismatch */
408 enum SQLITE_MISUSE = 21; /* Library used incorrectly */
409 enum SQLITE_NOLFS = 22; /* Uses OS features not supported on host */
410 enum SQLITE_AUTH = 23; /* Authorization denied */
411 enum SQLITE_FORMAT = 24; /* Not used */
412 enum SQLITE_RANGE = 25; /* 2nd parameter to sqlite3_bind out of range */
413 enum SQLITE_NOTADB = 26; /* File opened that is not a database file */
414 enum SQLITE_NOTICE = 27; /* Notifications from sqlite3_log() */
415 enum SQLITE_WARNING = 28; /* Warnings from sqlite3_log() */
416 enum SQLITE_ROW = 100; /* sqlite3_step() has another row ready */
417 enum SQLITE_DONE = 101; /* sqlite3_step() has finished executing */
418 /* end-of-error-codes */
419 
420 /*
421 ** CAPI3REF: Extended Result Codes
422 ** KEYWORDS: {extended result code definitions}
423 **
424 ** In its default configuration, SQLite API routines return one of 30 integer
425 ** [result codes].  However, experience has shown that many of
426 ** these result codes are too coarse-grained.  They do not provide as
427 ** much information about problems as programmers might like.  In an effort to
428 ** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8]
429 ** and later) include
430 ** support for additional result codes that provide more detailed information
431 ** about errors. These [extended result codes] are enabled or disabled
432 ** on a per database connection basis using the
433 ** [sqlite3_extended_result_codes()] API.  Or, the extended code for
434 ** the most recent error can be obtained using
435 ** [sqlite3_extended_errcode()].
436 */
437 enum SQLITE_IOERR_READ = SQLITE_IOERR | (1 << 8);
438 enum SQLITE_IOERR_SHORT_READ = SQLITE_IOERR | (2 << 8);
439 enum SQLITE_IOERR_WRITE = SQLITE_IOERR | (3 << 8);
440 enum SQLITE_IOERR_FSYNC = SQLITE_IOERR | (4 << 8);
441 enum SQLITE_IOERR_DIR_FSYNC = SQLITE_IOERR | (5 << 8);
442 enum SQLITE_IOERR_TRUNCATE = SQLITE_IOERR | (6 << 8);
443 enum SQLITE_IOERR_FSTAT = SQLITE_IOERR | (7 << 8);
444 enum SQLITE_IOERR_UNLOCK = SQLITE_IOERR | (8 << 8);
445 enum SQLITE_IOERR_RDLOCK = SQLITE_IOERR | (9 << 8);
446 enum SQLITE_IOERR_DELETE = SQLITE_IOERR | (10 << 8);
447 enum SQLITE_IOERR_BLOCKED = SQLITE_IOERR | (11 << 8);
448 enum SQLITE_IOERR_NOMEM = SQLITE_IOERR | (12 << 8);
449 enum SQLITE_IOERR_ACCESS = SQLITE_IOERR | (13 << 8);
450 enum SQLITE_IOERR_CHECKRESERVEDLOCK = SQLITE_IOERR | (14 << 8);
451 enum SQLITE_IOERR_LOCK = SQLITE_IOERR | (15 << 8);
452 enum SQLITE_IOERR_CLOSE = SQLITE_IOERR | (16 << 8);
453 enum SQLITE_IOERR_DIR_CLOSE = SQLITE_IOERR | (17 << 8);
454 enum SQLITE_IOERR_SHMOPEN = SQLITE_IOERR | (18 << 8);
455 enum SQLITE_IOERR_SHMSIZE = SQLITE_IOERR | (19 << 8);
456 enum SQLITE_IOERR_SHMLOCK = SQLITE_IOERR | (20 << 8);
457 enum SQLITE_IOERR_SHMMAP = SQLITE_IOERR | (21 << 8);
458 enum SQLITE_IOERR_SEEK = SQLITE_IOERR | (22 << 8);
459 enum SQLITE_IOERR_DELETE_NOENT = SQLITE_IOERR | (23 << 8);
460 enum SQLITE_IOERR_MMAP = SQLITE_IOERR | (24 << 8);
461 enum SQLITE_IOERR_GETTEMPPATH = SQLITE_IOERR | (25 << 8);
462 enum SQLITE_IOERR_CONVPATH = SQLITE_IOERR | (26 << 8);
463 enum SQLITE_IOERR_VNODE = SQLITE_IOERR | (27 << 8);
464 enum SQLITE_IOERR_AUTH = SQLITE_IOERR | (28 << 8);
465 enum SQLITE_IOERR_BEGIN_ATOMIC = SQLITE_IOERR | (29 << 8);
466 enum SQLITE_IOERR_COMMIT_ATOMIC = SQLITE_IOERR | (30 << 8);
467 enum SQLITE_IOERR_ROLLBACK_ATOMIC = SQLITE_IOERR | (31 << 8);
468 enum SQLITE_LOCKED_SHAREDCACHE = SQLITE_LOCKED | (1 << 8);
469 enum SQLITE_BUSY_RECOVERY = SQLITE_BUSY | (1 << 8);
470 enum SQLITE_BUSY_SNAPSHOT = SQLITE_BUSY | (2 << 8);
471 enum SQLITE_CANTOPEN_NOTEMPDIR = SQLITE_CANTOPEN | (1 << 8);
472 enum SQLITE_CANTOPEN_ISDIR = SQLITE_CANTOPEN | (2 << 8);
473 enum SQLITE_CANTOPEN_FULLPATH = SQLITE_CANTOPEN | (3 << 8);
474 enum SQLITE_CANTOPEN_CONVPATH = SQLITE_CANTOPEN | (4 << 8);
475 enum SQLITE_CORRUPT_VTAB = SQLITE_CORRUPT | (1 << 8);
476 enum SQLITE_READONLY_RECOVERY = SQLITE_READONLY | (1 << 8);
477 enum SQLITE_READONLY_CANTLOCK = SQLITE_READONLY | (2 << 8);
478 enum SQLITE_READONLY_ROLLBACK = SQLITE_READONLY | (3 << 8);
479 enum SQLITE_READONLY_DBMOVED = SQLITE_READONLY | (4 << 8);
480 enum SQLITE_ABORT_ROLLBACK = SQLITE_ABORT | (2 << 8);
481 enum SQLITE_CONSTRAINT_CHECK = SQLITE_CONSTRAINT | (1 << 8);
482 enum SQLITE_CONSTRAINT_COMMITHOOK = SQLITE_CONSTRAINT | (2 << 8);
483 enum SQLITE_CONSTRAINT_FOREIGNKEY = SQLITE_CONSTRAINT | (3 << 8);
484 enum SQLITE_CONSTRAINT_FUNCTION = SQLITE_CONSTRAINT | (4 << 8);
485 enum SQLITE_CONSTRAINT_NOTNULL = SQLITE_CONSTRAINT | (5 << 8);
486 enum SQLITE_CONSTRAINT_PRIMARYKEY = SQLITE_CONSTRAINT | (6 << 8);
487 enum SQLITE_CONSTRAINT_TRIGGER = SQLITE_CONSTRAINT | (7 << 8);
488 enum SQLITE_CONSTRAINT_UNIQUE = SQLITE_CONSTRAINT | (8 << 8);
489 enum SQLITE_CONSTRAINT_VTAB = SQLITE_CONSTRAINT | (9 << 8);
490 enum SQLITE_CONSTRAINT_ROWID = SQLITE_CONSTRAINT | (10 << 8);
491 enum SQLITE_NOTICE_RECOVER_WAL = SQLITE_NOTICE | (1 << 8);
492 enum SQLITE_NOTICE_RECOVER_ROLLBACK = SQLITE_NOTICE | (2 << 8);
493 enum SQLITE_WARNING_AUTOINDEX = SQLITE_WARNING | (1 << 8);
494 enum SQLITE_AUTH_USER = SQLITE_AUTH | (1 << 8);
495 enum SQLITE_OK_LOAD_PERMANENTLY = SQLITE_OK | (1 << 8);
496 
497 /*
498 ** CAPI3REF: Flags For File Open Operations
499 **
500 ** These bit values are intended for use in the
501 ** 3rd parameter to the [sqlite3_open_v2()] interface and
502 ** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
503 */
504 enum SQLITE_OPEN_READONLY = 0x00000001; /* Ok for sqlite3_open_v2() */
505 enum SQLITE_OPEN_READWRITE = 0x00000002; /* Ok for sqlite3_open_v2() */
506 enum SQLITE_OPEN_CREATE = 0x00000004; /* Ok for sqlite3_open_v2() */
507 enum SQLITE_OPEN_DELETEONCLOSE = 0x00000008; /* VFS only */
508 enum SQLITE_OPEN_EXCLUSIVE = 0x00000010; /* VFS only */
509 enum SQLITE_OPEN_AUTOPROXY = 0x00000020; /* VFS only */
510 enum SQLITE_OPEN_URI = 0x00000040; /* Ok for sqlite3_open_v2() */
511 enum SQLITE_OPEN_MEMORY = 0x00000080; /* Ok for sqlite3_open_v2() */
512 enum SQLITE_OPEN_MAIN_DB = 0x00000100; /* VFS only */
513 enum SQLITE_OPEN_TEMP_DB = 0x00000200; /* VFS only */
514 enum SQLITE_OPEN_TRANSIENT_DB = 0x00000400; /* VFS only */
515 enum SQLITE_OPEN_MAIN_JOURNAL = 0x00000800; /* VFS only */
516 enum SQLITE_OPEN_TEMP_JOURNAL = 0x00001000; /* VFS only */
517 enum SQLITE_OPEN_SUBJOURNAL = 0x00002000; /* VFS only */
518 enum SQLITE_OPEN_MASTER_JOURNAL = 0x00004000; /* VFS only */
519 enum SQLITE_OPEN_NOMUTEX = 0x00008000; /* Ok for sqlite3_open_v2() */
520 enum SQLITE_OPEN_FULLMUTEX = 0x00010000; /* Ok for sqlite3_open_v2() */
521 enum SQLITE_OPEN_SHAREDCACHE = 0x00020000; /* Ok for sqlite3_open_v2() */
522 enum SQLITE_OPEN_PRIVATECACHE = 0x00040000; /* Ok for sqlite3_open_v2() */
523 enum SQLITE_OPEN_WAL = 0x00080000; /* VFS only */
524 
525 /* Reserved:                         0x00F00000 */
526 
527 /*
528 ** CAPI3REF: Device Characteristics
529 **
530 ** The xDeviceCharacteristics method of the [sqlite3_io_methods]
531 ** object returns an integer which is a vector of these
532 ** bit values expressing I/O characteristics of the mass storage
533 ** device that holds the file that the [sqlite3_io_methods]
534 ** refers to.
535 **
536 ** The SQLITE_IOCAP_ATOMIC property means that all writes of
537 ** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
538 ** mean that writes of blocks that are nnn bytes in size and
539 ** are aligned to an address which is an integer multiple of
540 ** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
541 ** that when data is appended to a file, the data is appended
542 ** first then the size of the file is extended, never the other
543 ** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
544 ** information is written to disk in the same order as calls
545 ** to xWrite().  The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
546 ** after reboot following a crash or power loss, the only bytes in a
547 ** file that were written at the application level might have changed
548 ** and that adjacent bytes, even bytes within the same sector are
549 ** guaranteed to be unchanged.  The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
550 ** flag indicates that a file cannot be deleted when open.  The
551 ** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
552 ** read-only media and cannot be changed even by processes with
553 ** elevated privileges.
554 **
555 ** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying
556 ** filesystem supports doing multiple write operations atomically when those
557 ** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and
558 ** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].
559 */
560 enum SQLITE_IOCAP_ATOMIC = 0x00000001;
561 enum SQLITE_IOCAP_ATOMIC512 = 0x00000002;
562 enum SQLITE_IOCAP_ATOMIC1K = 0x00000004;
563 enum SQLITE_IOCAP_ATOMIC2K = 0x00000008;
564 enum SQLITE_IOCAP_ATOMIC4K = 0x00000010;
565 enum SQLITE_IOCAP_ATOMIC8K = 0x00000020;
566 enum SQLITE_IOCAP_ATOMIC16K = 0x00000040;
567 enum SQLITE_IOCAP_ATOMIC32K = 0x00000080;
568 enum SQLITE_IOCAP_ATOMIC64K = 0x00000100;
569 enum SQLITE_IOCAP_SAFE_APPEND = 0x00000200;
570 enum SQLITE_IOCAP_SEQUENTIAL = 0x00000400;
571 enum SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN = 0x00000800;
572 enum SQLITE_IOCAP_POWERSAFE_OVERWRITE = 0x00001000;
573 enum SQLITE_IOCAP_IMMUTABLE = 0x00002000;
574 enum SQLITE_IOCAP_BATCH_ATOMIC = 0x00004000;
575 
576 /*
577 ** CAPI3REF: File Locking Levels
578 **
579 ** SQLite uses one of these integer values as the second
580 ** argument to calls it makes to the xLock() and xUnlock() methods
581 ** of an [sqlite3_io_methods] object.
582 */
583 enum SQLITE_LOCK_NONE = 0;
584 enum SQLITE_LOCK_SHARED = 1;
585 enum SQLITE_LOCK_RESERVED = 2;
586 enum SQLITE_LOCK_PENDING = 3;
587 enum SQLITE_LOCK_EXCLUSIVE = 4;
588 
589 /*
590 ** CAPI3REF: Synchronization Type Flags
591 **
592 ** When SQLite invokes the xSync() method of an
593 ** [sqlite3_io_methods] object it uses a combination of
594 ** these integer values as the second argument.
595 **
596 ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
597 ** sync operation only needs to flush data to mass storage.  Inode
598 ** information need not be flushed. If the lower four bits of the flag
599 ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
600 ** If the lower four bits equal SQLITE_SYNC_FULL, that means
601 ** to use Mac OS X style fullsync instead of fsync().
602 **
603 ** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
604 ** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
605 ** settings.  The [synchronous pragma] determines when calls to the
606 ** xSync VFS method occur and applies uniformly across all platforms.
607 ** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
608 ** energetic or rigorous or forceful the sync operations are and
609 ** only make a difference on Mac OSX for the default SQLite code.
610 ** (Third-party VFS implementations might also make the distinction
611 ** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
612 ** operating systems natively supported by SQLite, only Mac OSX
613 ** cares about the difference.)
614 */
615 enum SQLITE_SYNC_NORMAL = 0x00002;
616 enum SQLITE_SYNC_FULL = 0x00003;
617 enum SQLITE_SYNC_DATAONLY = 0x00010;
618 
619 /*
620 ** CAPI3REF: OS Interface Open File Handle
621 **
622 ** An [sqlite3_file] object represents an open file in the
623 ** [sqlite3_vfs | OS interface layer].  Individual OS interface
624 ** implementations will
625 ** want to subclass this object by appending additional fields
626 ** for their own use.  The pMethods entry is a pointer to an
627 ** [sqlite3_io_methods] object that defines methods for performing
628 ** I/O operations on the open file.
629 */
630 struct sqlite3_file
631 {
632  /* Methods for an open file */
633 
634     /*
635     ** CAPI3REF: OS Interface File Virtual Methods Object
636     **
637     ** Every file opened by the [sqlite3_vfs.xOpen] method populates an
638     ** [sqlite3_file] object (or, more commonly, a subclass of the
639     ** [sqlite3_file] object) with a pointer to an instance of this object.
640     ** This object defines the methods used to perform various operations
641     ** against the open file represented by the [sqlite3_file] object.
642     **
643     ** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
644     ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
645     ** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed.  The
646     ** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
647     ** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
648     ** to NULL.
649     **
650     ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
651     ** [SQLITE_SYNC_FULL].  The first choice is the normal fsync().
652     ** The second choice is a Mac OS X style fullsync.  The [SQLITE_SYNC_DATAONLY]
653     ** flag may be ORed in to indicate that only the data of the file
654     ** and not its inode needs to be synced.
655     **
656     ** The integer values to xLock() and xUnlock() are one of
657     ** <ul>
658     ** <li> [SQLITE_LOCK_NONE],
659     ** <li> [SQLITE_LOCK_SHARED],
660     ** <li> [SQLITE_LOCK_RESERVED],
661     ** <li> [SQLITE_LOCK_PENDING], or
662     ** <li> [SQLITE_LOCK_EXCLUSIVE].
663     ** </ul>
664     ** xLock() increases the lock. xUnlock() decreases the lock.
665     ** The xCheckReservedLock() method checks whether any database connection,
666     ** either in this process or in some other process, is holding a RESERVED,
667     ** PENDING, or EXCLUSIVE lock on the file.  It returns true
668     ** if such a lock exists and false otherwise.
669     **
670     ** The xFileControl() method is a generic interface that allows custom
671     ** VFS implementations to directly control an open file using the
672     ** [sqlite3_file_control()] interface.  The second "op" argument is an
673     ** integer opcode.  The third argument is a generic pointer intended to
674     ** point to a structure that may contain arguments or space in which to
675     ** write return values.  Potential uses for xFileControl() might be
676     ** functions to enable blocking locks with timeouts, to change the
677     ** locking strategy (for example to use dot-file locks), to inquire
678     ** about the status of a lock, or to break stale locks.  The SQLite
679     ** core reserves all opcodes less than 100 for its own use.
680     ** A [file control opcodes | list of opcodes] less than 100 is available.
681     ** Applications that define a custom xFileControl method should use opcodes
682     ** greater than 100 to avoid conflicts.  VFS implementations should
683     ** return [SQLITE_NOTFOUND] for file control opcodes that they do not
684     ** recognize.
685     **
686     ** The xSectorSize() method returns the sector size of the
687     ** device that underlies the file.  The sector size is the
688     ** minimum write that can be performed without disturbing
689     ** other bytes in the file.  The xDeviceCharacteristics()
690     ** method returns a bit vector describing behaviors of the
691     ** underlying device:
692     **
693     ** <ul>
694     ** <li> [SQLITE_IOCAP_ATOMIC]
695     ** <li> [SQLITE_IOCAP_ATOMIC512]
696     ** <li> [SQLITE_IOCAP_ATOMIC1K]
697     ** <li> [SQLITE_IOCAP_ATOMIC2K]
698     ** <li> [SQLITE_IOCAP_ATOMIC4K]
699     ** <li> [SQLITE_IOCAP_ATOMIC8K]
700     ** <li> [SQLITE_IOCAP_ATOMIC16K]
701     ** <li> [SQLITE_IOCAP_ATOMIC32K]
702     ** <li> [SQLITE_IOCAP_ATOMIC64K]
703     ** <li> [SQLITE_IOCAP_SAFE_APPEND]
704     ** <li> [SQLITE_IOCAP_SEQUENTIAL]
705     ** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN]
706     ** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE]
707     ** <li> [SQLITE_IOCAP_IMMUTABLE]
708     ** <li> [SQLITE_IOCAP_BATCH_ATOMIC]
709     ** </ul>
710     **
711     ** The SQLITE_IOCAP_ATOMIC property means that all writes of
712     ** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
713     ** mean that writes of blocks that are nnn bytes in size and
714     ** are aligned to an address which is an integer multiple of
715     ** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
716     ** that when data is appended to a file, the data is appended
717     ** first then the size of the file is extended, never the other
718     ** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
719     ** information is written to disk in the same order as calls
720     ** to xWrite().
721     **
722     ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
723     ** in the unread portions of the buffer with zeros.  A VFS that
724     ** fails to zero-fill short reads might seem to work.  However,
725     ** failure to zero-fill short reads will eventually lead to
726     ** database corruption.
727     */
728 
729     struct sqlite3_io_methods
730     {
731         int iVersion;
732         int function(sqlite3_file*) xClose;
733         int function(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst) xRead;
734         int function(sqlite3_file*, const(void)*, int iAmt, sqlite3_int64 iOfst) xWrite;
735         int function(sqlite3_file*, sqlite3_int64 size) xTruncate;
736         int function(sqlite3_file*, int flags) xSync;
737         int function(sqlite3_file*, sqlite3_int64* pSize) xFileSize;
738         int function(sqlite3_file*, int) xLock;
739         int function(sqlite3_file*, int) xUnlock;
740         int function(sqlite3_file*, int* pResOut) xCheckReservedLock;
741         int function(sqlite3_file*, int op, void* pArg) xFileControl;
742         int function(sqlite3_file*) xSectorSize;
743         int function(sqlite3_file*) xDeviceCharacteristics;
744         /* Methods above are valid for version 1 */
745         int function(sqlite3_file*, int iPg, int pgsz, int, void**) xShmMap;
746         int function(sqlite3_file*, int offset, int n, int flags) xShmLock;
747         void function(sqlite3_file*) xShmBarrier;
748         int function(sqlite3_file*, int deleteFlag) xShmUnmap;
749         /* Methods above are valid for version 2 */
750         int function(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void** pp) xFetch;
751         int function(sqlite3_file*, sqlite3_int64 iOfst, void* p) xUnfetch;
752         /* Methods above are valid for version 3 */
753         /* Additional methods may be added in future releases */
754     }
755 
756     const(sqlite3_io_methods)* pMethods;
757 }
758 
759 struct sqlite3_io_methods
760 {
761     int iVersion;
762     int function(sqlite3_file*) xClose;
763     int function(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst) xRead;
764     int function(sqlite3_file*, const(void)*, int iAmt, sqlite3_int64 iOfst) xWrite;
765     int function(sqlite3_file*, sqlite3_int64 size) xTruncate;
766     int function(sqlite3_file*, int flags) xSync;
767     int function(sqlite3_file*, sqlite3_int64* pSize) xFileSize;
768     int function(sqlite3_file*, int) xLock;
769     int function(sqlite3_file*, int) xUnlock;
770     int function(sqlite3_file*, int* pResOut) xCheckReservedLock;
771     int function(sqlite3_file*, int op, void* pArg) xFileControl;
772     int function(sqlite3_file*) xSectorSize;
773     int function(sqlite3_file*) xDeviceCharacteristics;
774     int function(sqlite3_file*, int iPg, int pgsz, int, void**) xShmMap;
775     int function(sqlite3_file*, int offset, int n, int flags) xShmLock;
776     void function(sqlite3_file*) xShmBarrier;
777     int function(sqlite3_file*, int deleteFlag) xShmUnmap;
778     int function(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void** pp) xFetch;
779     int function(sqlite3_file*, sqlite3_int64 iOfst, void* p) xUnfetch;
780 }
781 
782 /*
783 ** CAPI3REF: Standard File Control Opcodes
784 ** KEYWORDS: {file control opcodes} {file control opcode}
785 **
786 ** These integer constants are opcodes for the xFileControl method
787 ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
788 ** interface.
789 **
790 ** <ul>
791 ** <li>[[SQLITE_FCNTL_LOCKSTATE]]
792 ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
793 ** opcode causes the xFileControl method to write the current state of
794 ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
795 ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
796 ** into an integer that the pArg argument points to. This capability
797 ** is used during testing and is only available when the SQLITE_TEST
798 ** compile-time option is used.
799 **
800 ** <li>[[SQLITE_FCNTL_SIZE_HINT]]
801 ** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
802 ** layer a hint of how large the database file will grow to be during the
803 ** current transaction.  This hint is not guaranteed to be accurate but it
804 ** is often close.  The underlying VFS might choose to preallocate database
805 ** file space based on this hint in order to help writes to the database
806 ** file run faster.
807 **
808 ** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
809 ** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
810 ** extends and truncates the database file in chunks of a size specified
811 ** by the user. The fourth argument to [sqlite3_file_control()] should
812 ** point to an integer (type int) containing the new chunk-size to use
813 ** for the nominated database. Allocating database file space in large
814 ** chunks (say 1MB at a time), may reduce file-system fragmentation and
815 ** improve performance on some systems.
816 **
817 ** <li>[[SQLITE_FCNTL_FILE_POINTER]]
818 ** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
819 ** to the [sqlite3_file] object associated with a particular database
820 ** connection.  See also [SQLITE_FCNTL_JOURNAL_POINTER].
821 **
822 ** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]]
823 ** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer
824 ** to the [sqlite3_file] object associated with the journal file (either
825 ** the [rollback journal] or the [write-ahead log]) for a particular database
826 ** connection.  See also [SQLITE_FCNTL_FILE_POINTER].
827 **
828 ** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
829 ** No longer in use.
830 **
831 ** <li>[[SQLITE_FCNTL_SYNC]]
832 ** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
833 ** sent to the VFS immediately before the xSync method is invoked on a
834 ** database file descriptor. Or, if the xSync method is not invoked
835 ** because the user has configured SQLite with
836 ** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place
837 ** of the xSync method. In most cases, the pointer argument passed with
838 ** this file-control is NULL. However, if the database file is being synced
839 ** as part of a multi-database commit, the argument points to a nul-terminated
840 ** string containing the transactions master-journal file name. VFSes that
841 ** do not need this signal should silently ignore this opcode. Applications
842 ** should not call [sqlite3_file_control()] with this opcode as doing so may
843 ** disrupt the operation of the specialized VFSes that do require it.
844 **
845 ** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
846 ** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
847 ** and sent to the VFS after a transaction has been committed immediately
848 ** but before the database is unlocked. VFSes that do not need this signal
849 ** should silently ignore this opcode. Applications should not call
850 ** [sqlite3_file_control()] with this opcode as doing so may disrupt the
851 ** operation of the specialized VFSes that do require it.
852 **
853 ** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
854 ** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
855 ** retry counts and intervals for certain disk I/O operations for the
856 ** windows [VFS] in order to provide robustness in the presence of
857 ** anti-virus programs.  By default, the windows VFS will retry file read,
858 ** file write, and file delete operations up to 10 times, with a delay
859 ** of 25 milliseconds before the first retry and with the delay increasing
860 ** by an additional 25 milliseconds with each subsequent retry.  This
861 ** opcode allows these two values (10 retries and 25 milliseconds of delay)
862 ** to be adjusted.  The values are changed for all database connections
863 ** within the same process.  The argument is a pointer to an array of two
864 ** integers where the first integer is the new retry count and the second
865 ** integer is the delay.  If either integer is negative, then the setting
866 ** is not changed but instead the prior value of that setting is written
867 ** into the array entry, allowing the current retry settings to be
868 ** interrogated.  The zDbName parameter is ignored.
869 **
870 ** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
871 ** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
872 ** persistent [WAL | Write Ahead Log] setting.  By default, the auxiliary
873 ** write ahead log and shared memory files used for transaction control
874 ** are automatically deleted when the latest connection to the database
875 ** closes.  Setting persistent WAL mode causes those files to persist after
876 ** close.  Persisting the files is useful when other processes that do not
877 ** have write permission on the directory containing the database file want
878 ** to read the database file, as the WAL and shared memory files must exist
879 ** in order for the database to be readable.  The fourth parameter to
880 ** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
881 ** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
882 ** WAL mode.  If the integer is -1, then it is overwritten with the current
883 ** WAL persistence setting.
884 **
885 ** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
886 ** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
887 ** persistent "powersafe-overwrite" or "PSOW" setting.  The PSOW setting
888 ** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
889 ** xDeviceCharacteristics methods. The fourth parameter to
890 ** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
891 ** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
892 ** mode.  If the integer is -1, then it is overwritten with the current
893 ** zero-damage mode setting.
894 **
895 ** <li>[[SQLITE_FCNTL_OVERWRITE]]
896 ** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
897 ** a write transaction to indicate that, unless it is rolled back for some
898 ** reason, the entire database file will be overwritten by the current
899 ** transaction. This is used by VACUUM operations.
900 **
901 ** <li>[[SQLITE_FCNTL_VFSNAME]]
902 ** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
903 ** all [VFSes] in the VFS stack.  The names are of all VFS shims and the
904 ** final bottom-level VFS are written into memory obtained from
905 ** [sqlite3_malloc()] and the result is stored in the char* variable
906 ** that the fourth parameter of [sqlite3_file_control()] points to.
907 ** The caller is responsible for freeing the memory when done.  As with
908 ** all file-control actions, there is no guarantee that this will actually
909 ** do anything.  Callers should initialize the char* variable to a NULL
910 ** pointer in case this file-control is not implemented.  This file-control
911 ** is intended for diagnostic use only.
912 **
913 ** <li>[[SQLITE_FCNTL_VFS_POINTER]]
914 ** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level
915 ** [VFSes] currently in use.  ^(The argument X in
916 ** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be
917 ** of type "[sqlite3_vfs] **".  This opcodes will set *X
918 ** to a pointer to the top-level VFS.)^
919 ** ^When there are multiple VFS shims in the stack, this opcode finds the
920 ** upper-most shim only.
921 **
922 ** <li>[[SQLITE_FCNTL_PRAGMA]]
923 ** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
924 ** file control is sent to the open [sqlite3_file] object corresponding
925 ** to the database file to which the pragma statement refers. ^The argument
926 ** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
927 ** pointers to strings (char**) in which the second element of the array
928 ** is the name of the pragma and the third element is the argument to the
929 ** pragma or NULL if the pragma has no argument.  ^The handler for an
930 ** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
931 ** of the char** argument point to a string obtained from [sqlite3_mprintf()]
932 ** or the equivalent and that string will become the result of the pragma or
933 ** the error message if the pragma fails. ^If the
934 ** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
935 ** [PRAGMA] processing continues.  ^If the [SQLITE_FCNTL_PRAGMA]
936 ** file control returns [SQLITE_OK], then the parser assumes that the
937 ** VFS has handled the PRAGMA itself and the parser generates a no-op
938 ** prepared statement if result string is NULL, or that returns a copy
939 ** of the result string if the string is non-NULL.
940 ** ^If the [SQLITE_FCNTL_PRAGMA] file control returns
941 ** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
942 ** that the VFS encountered an error while handling the [PRAGMA] and the
943 ** compilation of the PRAGMA fails with an error.  ^The [SQLITE_FCNTL_PRAGMA]
944 ** file control occurs at the beginning of pragma statement analysis and so
945 ** it is able to override built-in [PRAGMA] statements.
946 **
947 ** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
948 ** ^The [SQLITE_FCNTL_BUSYHANDLER]
949 ** file-control may be invoked by SQLite on the database file handle
950 ** shortly after it is opened in order to provide a custom VFS with access
951 ** to the connections busy-handler callback. The argument is of type (void **)
952 ** - an array of two (void *) values. The first (void *) actually points
953 ** to a function of type (int (*)(void *)). In order to invoke the connections
954 ** busy-handler, this function should be invoked with the second (void *) in
955 ** the array as the only argument. If it returns non-zero, then the operation
956 ** should be retried. If it returns zero, the custom VFS should abandon the
957 ** current operation.
958 **
959 ** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
960 ** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
961 ** to have SQLite generate a
962 ** temporary filename using the same algorithm that is followed to generate
963 ** temporary filenames for TEMP tables and other internal uses.  The
964 ** argument should be a char** which will be filled with the filename
965 ** written into memory obtained from [sqlite3_malloc()].  The caller should
966 ** invoke [sqlite3_free()] on the result to avoid a memory leak.
967 **
968 ** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
969 ** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
970 ** maximum number of bytes that will be used for memory-mapped I/O.
971 ** The argument is a pointer to a value of type sqlite3_int64 that
972 ** is an advisory maximum number of bytes in the file to memory map.  The
973 ** pointer is overwritten with the old value.  The limit is not changed if
974 ** the value originally pointed to is negative, and so the current limit
975 ** can be queried by passing in a pointer to a negative number.  This
976 ** file-control is used internally to implement [PRAGMA mmap_size].
977 **
978 ** <li>[[SQLITE_FCNTL_TRACE]]
979 ** The [SQLITE_FCNTL_TRACE] file control provides advisory information
980 ** to the VFS about what the higher layers of the SQLite stack are doing.
981 ** This file control is used by some VFS activity tracing [shims].
982 ** The argument is a zero-terminated string.  Higher layers in the
983 ** SQLite stack may generate instances of this file control if
984 ** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
985 **
986 ** <li>[[SQLITE_FCNTL_HAS_MOVED]]
987 ** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
988 ** pointer to an integer and it writes a boolean into that integer depending
989 ** on whether or not the file has been renamed, moved, or deleted since it
990 ** was first opened.
991 **
992 ** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]]
993 ** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the
994 ** underlying native file handle associated with a file handle.  This file
995 ** control interprets its argument as a pointer to a native file handle and
996 ** writes the resulting value there.
997 **
998 ** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
999 ** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging.  This
1000 ** opcode causes the xFileControl method to swap the file handle with the one
1001 ** pointed to by the pArg argument.  This capability is used during testing
1002 ** and only needs to be supported when SQLITE_TEST is defined.
1003 **
1004 ** <li>[[SQLITE_FCNTL_WAL_BLOCK]]
1005 ** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might
1006 ** be advantageous to block on the next WAL lock if the lock is not immediately
1007 ** available.  The WAL subsystem issues this signal during rare
1008 ** circumstances in order to fix a problem with priority inversion.
1009 ** Applications should <em>not</em> use this file-control.
1010 **
1011 ** <li>[[SQLITE_FCNTL_ZIPVFS]]
1012 ** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other
1013 ** VFS should return SQLITE_NOTFOUND for this opcode.
1014 **
1015 ** <li>[[SQLITE_FCNTL_RBU]]
1016 ** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by
1017 ** the RBU extension only.  All other VFS should return SQLITE_NOTFOUND for
1018 ** this opcode.
1019 **
1020 ** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]]
1021 ** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then
1022 ** the file descriptor is placed in "batch write mode", which
1023 ** means all subsequent write operations will be deferred and done
1024 ** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].  Systems
1025 ** that do not support batch atomic writes will return SQLITE_NOTFOUND.
1026 ** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to
1027 ** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or
1028 ** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make
1029 ** no VFS interface calls on the same [sqlite3_file] file descriptor
1030 ** except for calls to the xWrite method and the xFileControl method
1031 ** with [SQLITE_FCNTL_SIZE_HINT].
1032 **
1033 ** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]]
1034 ** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write
1035 ** operations since the previous successful call to
1036 ** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically.
1037 ** This file control returns [SQLITE_OK] if and only if the writes were
1038 ** all performed successfully and have been committed to persistent storage.
1039 ** ^Regardless of whether or not it is successful, this file control takes
1040 ** the file descriptor out of batch write mode so that all subsequent
1041 ** write operations are independent.
1042 ** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without
1043 ** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1044 **
1045 ** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]]
1046 ** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write
1047 ** operations since the previous successful call to
1048 ** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back.
1049 ** ^This file control takes the file descriptor out of batch write mode
1050 ** so that all subsequent write operations are independent.
1051 ** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without
1052 ** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1053 ** </ul>
1054 */
1055 enum SQLITE_FCNTL_LOCKSTATE = 1;
1056 enum SQLITE_FCNTL_GET_LOCKPROXYFILE = 2;
1057 enum SQLITE_FCNTL_SET_LOCKPROXYFILE = 3;
1058 enum SQLITE_FCNTL_LAST_ERRNO = 4;
1059 enum SQLITE_FCNTL_SIZE_HINT = 5;
1060 enum SQLITE_FCNTL_CHUNK_SIZE = 6;
1061 enum SQLITE_FCNTL_FILE_POINTER = 7;
1062 enum SQLITE_FCNTL_SYNC_OMITTED = 8;
1063 enum SQLITE_FCNTL_WIN32_AV_RETRY = 9;
1064 enum SQLITE_FCNTL_PERSIST_WAL = 10;
1065 enum SQLITE_FCNTL_OVERWRITE = 11;
1066 enum SQLITE_FCNTL_VFSNAME = 12;
1067 enum SQLITE_FCNTL_POWERSAFE_OVERWRITE = 13;
1068 enum SQLITE_FCNTL_PRAGMA = 14;
1069 enum SQLITE_FCNTL_BUSYHANDLER = 15;
1070 enum SQLITE_FCNTL_TEMPFILENAME = 16;
1071 enum SQLITE_FCNTL_MMAP_SIZE = 18;
1072 enum SQLITE_FCNTL_TRACE = 19;
1073 enum SQLITE_FCNTL_HAS_MOVED = 20;
1074 enum SQLITE_FCNTL_SYNC = 21;
1075 enum SQLITE_FCNTL_COMMIT_PHASETWO = 22;
1076 enum SQLITE_FCNTL_WIN32_SET_HANDLE = 23;
1077 enum SQLITE_FCNTL_WAL_BLOCK = 24;
1078 enum SQLITE_FCNTL_ZIPVFS = 25;
1079 enum SQLITE_FCNTL_RBU = 26;
1080 enum SQLITE_FCNTL_VFS_POINTER = 27;
1081 enum SQLITE_FCNTL_JOURNAL_POINTER = 28;
1082 enum SQLITE_FCNTL_WIN32_GET_HANDLE = 29;
1083 enum SQLITE_FCNTL_PDB = 30;
1084 enum SQLITE_FCNTL_BEGIN_ATOMIC_WRITE = 31;
1085 enum SQLITE_FCNTL_COMMIT_ATOMIC_WRITE = 32;
1086 enum SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE = 33;
1087 
1088 /* deprecated names */
1089 enum SQLITE_GET_LOCKPROXYFILE = SQLITE_FCNTL_GET_LOCKPROXYFILE;
1090 enum SQLITE_SET_LOCKPROXYFILE = SQLITE_FCNTL_SET_LOCKPROXYFILE;
1091 enum SQLITE_LAST_ERRNO = SQLITE_FCNTL_LAST_ERRNO;
1092 
1093 /*
1094 ** CAPI3REF: Mutex Handle
1095 **
1096 ** The mutex module within SQLite defines [sqlite3_mutex] to be an
1097 ** abstract type for a mutex object.  The SQLite core never looks
1098 ** at the internal representation of an [sqlite3_mutex].  It only
1099 ** deals with pointers to the [sqlite3_mutex] object.
1100 **
1101 ** Mutexes are created using [sqlite3_mutex_alloc()].
1102 */
1103 struct sqlite3_mutex;
1104 
1105 /*
1106 ** CAPI3REF: Loadable Extension Thunk
1107 **
1108 ** A pointer to the opaque sqlite3_api_routines structure is passed as
1109 ** the third parameter to entry points of [loadable extensions].  This
1110 ** structure must be typedefed in order to work around compiler warnings
1111 ** on some platforms.
1112 */
1113 struct sqlite3_api_routines;
1114 
1115 /*
1116 ** CAPI3REF: OS Interface Object
1117 **
1118 ** An instance of the sqlite3_vfs object defines the interface between
1119 ** the SQLite core and the underlying operating system.  The "vfs"
1120 ** in the name of the object stands for "virtual file system".  See
1121 ** the [VFS | VFS documentation] for further information.
1122 **
1123 ** The value of the iVersion field is initially 1 but may be larger in
1124 ** future versions of SQLite.  Additional fields may be appended to this
1125 ** object when the iVersion value is increased.  Note that the structure
1126 ** of the sqlite3_vfs object changes in the transaction between
1127 ** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
1128 ** modified.
1129 **
1130 ** The szOsFile field is the size of the subclassed [sqlite3_file]
1131 ** structure used by this VFS.  mxPathname is the maximum length of
1132 ** a pathname in this VFS.
1133 **
1134 ** Registered sqlite3_vfs objects are kept on a linked list formed by
1135 ** the pNext pointer.  The [sqlite3_vfs_register()]
1136 ** and [sqlite3_vfs_unregister()] interfaces manage this list
1137 ** in a thread-safe way.  The [sqlite3_vfs_find()] interface
1138 ** searches the list.  Neither the application code nor the VFS
1139 ** implementation should use the pNext pointer.
1140 **
1141 ** The pNext field is the only field in the sqlite3_vfs
1142 ** structure that SQLite will ever modify.  SQLite will only access
1143 ** or modify this field while holding a particular static mutex.
1144 ** The application should never modify anything within the sqlite3_vfs
1145 ** object once the object has been registered.
1146 **
1147 ** The zName field holds the name of the VFS module.  The name must
1148 ** be unique across all VFS modules.
1149 **
1150 ** [[sqlite3_vfs.xOpen]]
1151 ** ^SQLite guarantees that the zFilename parameter to xOpen
1152 ** is either a NULL pointer or string obtained
1153 ** from xFullPathname() with an optional suffix added.
1154 ** ^If a suffix is added to the zFilename parameter, it will
1155 ** consist of a single "-" character followed by no more than
1156 ** 11 alphanumeric and/or "-" characters.
1157 ** ^SQLite further guarantees that
1158 ** the string will be valid and unchanged until xClose() is
1159 ** called. Because of the previous sentence,
1160 ** the [sqlite3_file] can safely store a pointer to the
1161 ** filename if it needs to remember the filename for some reason.
1162 ** If the zFilename parameter to xOpen is a NULL pointer then xOpen
1163 ** must invent its own temporary name for the file.  ^Whenever the
1164 ** xFilename parameter is NULL it will also be the case that the
1165 ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
1166 **
1167 ** The flags argument to xOpen() includes all bits set in
1168 ** the flags argument to [sqlite3_open_v2()].  Or if [sqlite3_open()]
1169 ** or [sqlite3_open16()] is used, then flags includes at least
1170 ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
1171 ** If xOpen() opens a file read-only then it sets *pOutFlags to
1172 ** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
1173 **
1174 ** ^(SQLite will also add one of the following flags to the xOpen()
1175 ** call, depending on the object being opened:
1176 **
1177 ** <ul>
1178 ** <li>  [SQLITE_OPEN_MAIN_DB]
1179 ** <li>  [SQLITE_OPEN_MAIN_JOURNAL]
1180 ** <li>  [SQLITE_OPEN_TEMP_DB]
1181 ** <li>  [SQLITE_OPEN_TEMP_JOURNAL]
1182 ** <li>  [SQLITE_OPEN_TRANSIENT_DB]
1183 ** <li>  [SQLITE_OPEN_SUBJOURNAL]
1184 ** <li>  [SQLITE_OPEN_MASTER_JOURNAL]
1185 ** <li>  [SQLITE_OPEN_WAL]
1186 ** </ul>)^
1187 **
1188 ** The file I/O implementation can use the object type flags to
1189 ** change the way it deals with files.  For example, an application
1190 ** that does not care about crash recovery or rollback might make
1191 ** the open of a journal file a no-op.  Writes to this journal would
1192 ** also be no-ops, and any attempt to read the journal would return
1193 ** SQLITE_IOERR.  Or the implementation might recognize that a database
1194 ** file will be doing page-aligned sector reads and writes in a random
1195 ** order and set up its I/O subsystem accordingly.
1196 **
1197 ** SQLite might also add one of the following flags to the xOpen method:
1198 **
1199 ** <ul>
1200 ** <li> [SQLITE_OPEN_DELETEONCLOSE]
1201 ** <li> [SQLITE_OPEN_EXCLUSIVE]
1202 ** </ul>
1203 **
1204 ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
1205 ** deleted when it is closed.  ^The [SQLITE_OPEN_DELETEONCLOSE]
1206 ** will be set for TEMP databases and their journals, transient
1207 ** databases, and subjournals.
1208 **
1209 ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
1210 ** with the [SQLITE_OPEN_CREATE] flag, which are both directly
1211 ** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
1212 ** API.  The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
1213 ** SQLITE_OPEN_CREATE, is used to indicate that file should always
1214 ** be created, and that it is an error if it already exists.
1215 ** It is <i>not</i> used to indicate the file should be opened
1216 ** for exclusive access.
1217 **
1218 ** ^At least szOsFile bytes of memory are allocated by SQLite
1219 ** to hold the  [sqlite3_file] structure passed as the third
1220 ** argument to xOpen.  The xOpen method does not have to
1221 ** allocate the structure; it should just fill it in.  Note that
1222 ** the xOpen method must set the sqlite3_file.pMethods to either
1223 ** a valid [sqlite3_io_methods] object or to NULL.  xOpen must do
1224 ** this even if the open fails.  SQLite expects that the sqlite3_file.pMethods
1225 ** element will be valid after xOpen returns regardless of the success
1226 ** or failure of the xOpen call.
1227 **
1228 ** [[sqlite3_vfs.xAccess]]
1229 ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
1230 ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
1231 ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
1232 ** to test whether a file is at least readable.   The file can be a
1233 ** directory.
1234 **
1235 ** ^SQLite will always allocate at least mxPathname+1 bytes for the
1236 ** output buffer xFullPathname.  The exact size of the output buffer
1237 ** is also passed as a parameter to both  methods. If the output buffer
1238 ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
1239 ** handled as a fatal error by SQLite, vfs implementations should endeavor
1240 ** to prevent this by setting mxPathname to a sufficiently large value.
1241 **
1242 ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
1243 ** interfaces are not strictly a part of the filesystem, but they are
1244 ** included in the VFS structure for completeness.
1245 ** The xRandomness() function attempts to return nBytes bytes
1246 ** of good-quality randomness into zOut.  The return value is
1247 ** the actual number of bytes of randomness obtained.
1248 ** The xSleep() method causes the calling thread to sleep for at
1249 ** least the number of microseconds given.  ^The xCurrentTime()
1250 ** method returns a Julian Day Number for the current date and time as
1251 ** a floating point value.
1252 ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
1253 ** Day Number multiplied by 86400000 (the number of milliseconds in
1254 ** a 24-hour day).
1255 ** ^SQLite will use the xCurrentTimeInt64() method to get the current
1256 ** date and time if that method is available (if iVersion is 2 or
1257 ** greater and the function pointer is not NULL) and will fall back
1258 ** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
1259 **
1260 ** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
1261 ** are not used by the SQLite core.  These optional interfaces are provided
1262 ** by some VFSes to facilitate testing of the VFS code. By overriding
1263 ** system calls with functions under its control, a test program can
1264 ** simulate faults and error conditions that would otherwise be difficult
1265 ** or impossible to induce.  The set of system calls that can be overridden
1266 ** varies from one VFS to another, and from one version of the same VFS to the
1267 ** next.  Applications that use these interfaces must be prepared for any
1268 ** or all of these interfaces to be NULL or for their behavior to change
1269 ** from one release to the next.  Applications must not attempt to access
1270 ** any of these methods if the iVersion of the VFS is less than 3.
1271 */
1272 alias sqlite3_syscall_ptr = void function();
1273 
1274 struct sqlite3_vfs
1275 {
1276     int iVersion; /* Structure version number (currently 3) */
1277     int szOsFile; /* Size of subclassed sqlite3_file */
1278     int mxPathname; /* Maximum file pathname length */
1279     sqlite3_vfs* pNext; /* Next registered VFS */
1280     const(char)* zName; /* Name of this virtual file system */
1281     void* pAppData; /* Pointer to application-specific data */
1282     int function(sqlite3_vfs*, const(char)* zName, sqlite3_file*, int flags, int* pOutFlags) xOpen;
1283     int function(sqlite3_vfs*, const(char)* zName, int syncDir) xDelete;
1284     int function(sqlite3_vfs*, const(char)* zName, int flags, int* pResOut) xAccess;
1285     int function(sqlite3_vfs*, const(char)* zName, int nOut, char* zOut) xFullPathname;
1286     void* function(sqlite3_vfs*, const(char)* zFilename) xDlOpen;
1287     void function(sqlite3_vfs*, int nByte, char* zErrMsg) xDlError;
1288     void function(sqlite3_vfs*, void*, const(char)* zSymbol) function(sqlite3_vfs*, void*, const(char)* zSymbol) xDlSym;
1289     void function(sqlite3_vfs*, void*) xDlClose;
1290     int function(sqlite3_vfs*, int nByte, char* zOut) xRandomness;
1291     int function(sqlite3_vfs*, int microseconds) xSleep;
1292     int function(sqlite3_vfs*, double*) xCurrentTime;
1293     int function(sqlite3_vfs*, int, char*) xGetLastError;
1294     /*
1295     ** The methods above are in version 1 of the sqlite_vfs object
1296     ** definition.  Those that follow are added in version 2 or later
1297     */
1298     int function(sqlite3_vfs*, sqlite3_int64*) xCurrentTimeInt64;
1299     /*
1300     ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
1301     ** Those below are for version 3 and greater.
1302     */
1303     int function(sqlite3_vfs*, const(char)* zName, sqlite3_syscall_ptr) xSetSystemCall;
1304     sqlite3_syscall_ptr function(sqlite3_vfs*, const(char)* zName) xGetSystemCall;
1305     const(char)* function(sqlite3_vfs*, const(char)* zName) xNextSystemCall;
1306     /*
1307     ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
1308     ** New fields may be appended in future versions.  The iVersion
1309     ** value will increment whenever this happens.
1310     */
1311 }
1312 
1313 /*
1314 ** CAPI3REF: Flags for the xAccess VFS method
1315 **
1316 ** These integer constants can be used as the third parameter to
1317 ** the xAccess method of an [sqlite3_vfs] object.  They determine
1318 ** what kind of permissions the xAccess method is looking for.
1319 ** With SQLITE_ACCESS_EXISTS, the xAccess method
1320 ** simply checks whether the file exists.
1321 ** With SQLITE_ACCESS_READWRITE, the xAccess method
1322 ** checks whether the named directory is both readable and writable
1323 ** (in other words, if files can be added, removed, and renamed within
1324 ** the directory).
1325 ** The SQLITE_ACCESS_READWRITE constant is currently used only by the
1326 ** [temp_store_directory pragma], though this could change in a future
1327 ** release of SQLite.
1328 ** With SQLITE_ACCESS_READ, the xAccess method
1329 ** checks whether the file is readable.  The SQLITE_ACCESS_READ constant is
1330 ** currently unused, though it might be used in a future release of
1331 ** SQLite.
1332 */
1333 enum SQLITE_ACCESS_EXISTS = 0;
1334 enum SQLITE_ACCESS_READWRITE = 1; /* Used by PRAGMA temp_store_directory */
1335 enum SQLITE_ACCESS_READ = 2; /* Unused */
1336 
1337 /*
1338 ** CAPI3REF: Flags for the xShmLock VFS method
1339 **
1340 ** These integer constants define the various locking operations
1341 ** allowed by the xShmLock method of [sqlite3_io_methods].  The
1342 ** following are the only legal combinations of flags to the
1343 ** xShmLock method:
1344 **
1345 ** <ul>
1346 ** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
1347 ** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
1348 ** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
1349 ** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
1350 ** </ul>
1351 **
1352 ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
1353 ** was given on the corresponding lock.
1354 **
1355 ** The xShmLock method can transition between unlocked and SHARED or
1356 ** between unlocked and EXCLUSIVE.  It cannot transition between SHARED
1357 ** and EXCLUSIVE.
1358 */
1359 enum SQLITE_SHM_UNLOCK = 1;
1360 enum SQLITE_SHM_LOCK = 2;
1361 enum SQLITE_SHM_SHARED = 4;
1362 enum SQLITE_SHM_EXCLUSIVE = 8;
1363 
1364 /*
1365 ** CAPI3REF: Maximum xShmLock index
1366 **
1367 ** The xShmLock method on [sqlite3_io_methods] may use values
1368 ** between 0 and this upper bound as its "offset" argument.
1369 ** The SQLite core will never attempt to acquire or release a
1370 ** lock outside of this range
1371 */
1372 enum SQLITE_SHM_NLOCK = 8;
1373 
1374 /*
1375 ** CAPI3REF: Initialize The SQLite Library
1376 **
1377 ** ^The sqlite3_initialize() routine initializes the
1378 ** SQLite library.  ^The sqlite3_shutdown() routine
1379 ** deallocates any resources that were allocated by sqlite3_initialize().
1380 ** These routines are designed to aid in process initialization and
1381 ** shutdown on embedded systems.  Workstation applications using
1382 ** SQLite normally do not need to invoke either of these routines.
1383 **
1384 ** A call to sqlite3_initialize() is an "effective" call if it is
1385 ** the first time sqlite3_initialize() is invoked during the lifetime of
1386 ** the process, or if it is the first time sqlite3_initialize() is invoked
1387 ** following a call to sqlite3_shutdown().  ^(Only an effective call
1388 ** of sqlite3_initialize() does any initialization.  All other calls
1389 ** are harmless no-ops.)^
1390 **
1391 ** A call to sqlite3_shutdown() is an "effective" call if it is the first
1392 ** call to sqlite3_shutdown() since the last sqlite3_initialize().  ^(Only
1393 ** an effective call to sqlite3_shutdown() does any deinitialization.
1394 ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
1395 **
1396 ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
1397 ** is not.  The sqlite3_shutdown() interface must only be called from a
1398 ** single thread.  All open [database connections] must be closed and all
1399 ** other SQLite resources must be deallocated prior to invoking
1400 ** sqlite3_shutdown().
1401 **
1402 ** Among other things, ^sqlite3_initialize() will invoke
1403 ** sqlite3_os_init().  Similarly, ^sqlite3_shutdown()
1404 ** will invoke sqlite3_os_end().
1405 **
1406 ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
1407 ** ^If for some reason, sqlite3_initialize() is unable to initialize
1408 ** the library (perhaps it is unable to allocate a needed resource such
1409 ** as a mutex) it returns an [error code] other than [SQLITE_OK].
1410 **
1411 ** ^The sqlite3_initialize() routine is called internally by many other
1412 ** SQLite interfaces so that an application usually does not need to
1413 ** invoke sqlite3_initialize() directly.  For example, [sqlite3_open()]
1414 ** calls sqlite3_initialize() so the SQLite library will be automatically
1415 ** initialized when [sqlite3_open()] is called if it has not be initialized
1416 ** already.  ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
1417 ** compile-time option, then the automatic calls to sqlite3_initialize()
1418 ** are omitted and the application must call sqlite3_initialize() directly
1419 ** prior to using any other SQLite interface.  For maximum portability,
1420 ** it is recommended that applications always invoke sqlite3_initialize()
1421 ** directly prior to using any other SQLite interface.  Future releases
1422 ** of SQLite may require this.  In other words, the behavior exhibited
1423 ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
1424 ** default behavior in some future release of SQLite.
1425 **
1426 ** The sqlite3_os_init() routine does operating-system specific
1427 ** initialization of the SQLite library.  The sqlite3_os_end()
1428 ** routine undoes the effect of sqlite3_os_init().  Typical tasks
1429 ** performed by these routines include allocation or deallocation
1430 ** of static resources, initialization of global variables,
1431 ** setting up a default [sqlite3_vfs] module, or setting up
1432 ** a default configuration using [sqlite3_config()].
1433 **
1434 ** The application should never invoke either sqlite3_os_init()
1435 ** or sqlite3_os_end() directly.  The application should only invoke
1436 ** sqlite3_initialize() and sqlite3_shutdown().  The sqlite3_os_init()
1437 ** interface is called automatically by sqlite3_initialize() and
1438 ** sqlite3_os_end() is called by sqlite3_shutdown().  Appropriate
1439 ** implementations for sqlite3_os_init() and sqlite3_os_end()
1440 ** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
1441 ** When [custom builds | built for other platforms]
1442 ** (using the [SQLITE_OS_OTHER=1] compile-time
1443 ** option) the application must supply a suitable implementation for
1444 ** sqlite3_os_init() and sqlite3_os_end().  An application-supplied
1445 ** implementation of sqlite3_os_init() or sqlite3_os_end()
1446 ** must return [SQLITE_OK] on success and some other [error code] upon
1447 ** failure.
1448 */
1449 int sqlite3_initialize();
1450 int sqlite3_shutdown();
1451 int sqlite3_os_init();
1452 int sqlite3_os_end();
1453 
1454 /*
1455 ** CAPI3REF: Configuring The SQLite Library
1456 **
1457 ** The sqlite3_config() interface is used to make global configuration
1458 ** changes to SQLite in order to tune SQLite to the specific needs of
1459 ** the application.  The default configuration is recommended for most
1460 ** applications and so this routine is usually not necessary.  It is
1461 ** provided to support rare applications with unusual needs.
1462 **
1463 ** <b>The sqlite3_config() interface is not threadsafe. The application
1464 ** must ensure that no other SQLite interfaces are invoked by other
1465 ** threads while sqlite3_config() is running.</b>
1466 **
1467 ** The sqlite3_config() interface
1468 ** may only be invoked prior to library initialization using
1469 ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
1470 ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
1471 ** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
1472 ** Note, however, that ^sqlite3_config() can be called as part of the
1473 ** implementation of an application-defined [sqlite3_os_init()].
1474 **
1475 ** The first argument to sqlite3_config() is an integer
1476 ** [configuration option] that determines
1477 ** what property of SQLite is to be configured.  Subsequent arguments
1478 ** vary depending on the [configuration option]
1479 ** in the first argument.
1480 **
1481 ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
1482 ** ^If the option is unknown or SQLite is unable to set the option
1483 ** then this routine returns a non-zero [error code].
1484 */
1485 int sqlite3_config(int, ...);
1486 
1487 /*
1488 ** CAPI3REF: Configure database connections
1489 ** METHOD: sqlite3
1490 **
1491 ** The sqlite3_db_config() interface is used to make configuration
1492 ** changes to a [database connection].  The interface is similar to
1493 ** [sqlite3_config()] except that the changes apply to a single
1494 ** [database connection] (specified in the first argument).
1495 **
1496 ** The second argument to sqlite3_db_config(D,V,...)  is the
1497 ** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
1498 ** that indicates what aspect of the [database connection] is being configured.
1499 ** Subsequent arguments vary depending on the configuration verb.
1500 **
1501 ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
1502 ** the call is considered successful.
1503 */
1504 int sqlite3_db_config(sqlite3*, int op, ...);
1505 
1506 /*
1507 ** CAPI3REF: Memory Allocation Routines
1508 **
1509 ** An instance of this object defines the interface between SQLite
1510 ** and low-level memory allocation routines.
1511 **
1512 ** This object is used in only one place in the SQLite interface.
1513 ** A pointer to an instance of this object is the argument to
1514 ** [sqlite3_config()] when the configuration option is
1515 ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
1516 ** By creating an instance of this object
1517 ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
1518 ** during configuration, an application can specify an alternative
1519 ** memory allocation subsystem for SQLite to use for all of its
1520 ** dynamic memory needs.
1521 **
1522 ** Note that SQLite comes with several [built-in memory allocators]
1523 ** that are perfectly adequate for the overwhelming majority of applications
1524 ** and that this object is only useful to a tiny minority of applications
1525 ** with specialized memory allocation requirements.  This object is
1526 ** also used during testing of SQLite in order to specify an alternative
1527 ** memory allocator that simulates memory out-of-memory conditions in
1528 ** order to verify that SQLite recovers gracefully from such
1529 ** conditions.
1530 **
1531 ** The xMalloc, xRealloc, and xFree methods must work like the
1532 ** malloc(), realloc() and free() functions from the standard C library.
1533 ** ^SQLite guarantees that the second argument to
1534 ** xRealloc is always a value returned by a prior call to xRoundup.
1535 **
1536 ** xSize should return the allocated size of a memory allocation
1537 ** previously obtained from xMalloc or xRealloc.  The allocated size
1538 ** is always at least as big as the requested size but may be larger.
1539 **
1540 ** The xRoundup method returns what would be the allocated size of
1541 ** a memory allocation given a particular requested size.  Most memory
1542 ** allocators round up memory allocations at least to the next multiple
1543 ** of 8.  Some allocators round up to a larger multiple or to a power of 2.
1544 ** Every memory allocation request coming in through [sqlite3_malloc()]
1545 ** or [sqlite3_realloc()] first calls xRoundup.  If xRoundup returns 0,
1546 ** that causes the corresponding memory allocation to fail.
1547 **
1548 ** The xInit method initializes the memory allocator.  For example,
1549 ** it might allocate any require mutexes or initialize internal data
1550 ** structures.  The xShutdown method is invoked (indirectly) by
1551 ** [sqlite3_shutdown()] and should deallocate any resources acquired
1552 ** by xInit.  The pAppData pointer is used as the only parameter to
1553 ** xInit and xShutdown.
1554 **
1555 ** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
1556 ** the xInit method, so the xInit method need not be threadsafe.  The
1557 ** xShutdown method is only called from [sqlite3_shutdown()] so it does
1558 ** not need to be threadsafe either.  For all other methods, SQLite
1559 ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1560 ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1561 ** it is by default) and so the methods are automatically serialized.
1562 ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1563 ** methods must be threadsafe or else make their own arrangements for
1564 ** serialization.
1565 **
1566 ** SQLite will never invoke xInit() more than once without an intervening
1567 ** call to xShutdown().
1568 */
1569 struct sqlite3_mem_methods
1570 {
1571     void* function(int) xMalloc; /* Memory allocation function */
1572     void function(void*) xFree; /* Free a prior allocation */
1573     void* function(void*, int) xRealloc; /* Resize an allocation */
1574     int function(void*) xSize; /* Return the size of an allocation */
1575     int function(int) xRoundup; /* Round up request size to allocation size */
1576     int function(void*) xInit; /* Initialize the memory allocator */
1577     void function(void*) xShutdown; /* Deinitialize the memory allocator */
1578     void* pAppData; /* Argument to xInit() and xShutdown() */
1579 }
1580 
1581 /*
1582 ** CAPI3REF: Configuration Options
1583 ** KEYWORDS: {configuration option}
1584 **
1585 ** These constants are the available integer configuration options that
1586 ** can be passed as the first argument to the [sqlite3_config()] interface.
1587 **
1588 ** New configuration options may be added in future releases of SQLite.
1589 ** Existing configuration options might be discontinued.  Applications
1590 ** should check the return code from [sqlite3_config()] to make sure that
1591 ** the call worked.  The [sqlite3_config()] interface will return a
1592 ** non-zero [error code] if a discontinued or unsupported configuration option
1593 ** is invoked.
1594 **
1595 ** <dl>
1596 ** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1597 ** <dd>There are no arguments to this option.  ^This option sets the
1598 ** [threading mode] to Single-thread.  In other words, it disables
1599 ** all mutexing and puts SQLite into a mode where it can only be used
1600 ** by a single thread.   ^If SQLite is compiled with
1601 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1602 ** it is not possible to change the [threading mode] from its default
1603 ** value of Single-thread and so [sqlite3_config()] will return
1604 ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
1605 ** configuration option.</dd>
1606 **
1607 ** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1608 ** <dd>There are no arguments to this option.  ^This option sets the
1609 ** [threading mode] to Multi-thread.  In other words, it disables
1610 ** mutexing on [database connection] and [prepared statement] objects.
1611 ** The application is responsible for serializing access to
1612 ** [database connections] and [prepared statements].  But other mutexes
1613 ** are enabled so that SQLite will be safe to use in a multi-threaded
1614 ** environment as long as no two threads attempt to use the same
1615 ** [database connection] at the same time.  ^If SQLite is compiled with
1616 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1617 ** it is not possible to set the Multi-thread [threading mode] and
1618 ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1619 ** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
1620 **
1621 ** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
1622 ** <dd>There are no arguments to this option.  ^This option sets the
1623 ** [threading mode] to Serialized. In other words, this option enables
1624 ** all mutexes including the recursive
1625 ** mutexes on [database connection] and [prepared statement] objects.
1626 ** In this mode (which is the default when SQLite is compiled with
1627 ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
1628 ** to [database connections] and [prepared statements] so that the
1629 ** application is free to use the same [database connection] or the
1630 ** same [prepared statement] in different threads at the same time.
1631 ** ^If SQLite is compiled with
1632 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1633 ** it is not possible to set the Serialized [threading mode] and
1634 ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1635 ** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
1636 **
1637 ** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
1638 ** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is
1639 ** a pointer to an instance of the [sqlite3_mem_methods] structure.
1640 ** The argument specifies
1641 ** alternative low-level memory allocation routines to be used in place of
1642 ** the memory allocation routines built into SQLite.)^ ^SQLite makes
1643 ** its own private copy of the content of the [sqlite3_mem_methods] structure
1644 ** before the [sqlite3_config()] call returns.</dd>
1645 **
1646 ** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
1647 ** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which
1648 ** is a pointer to an instance of the [sqlite3_mem_methods] structure.
1649 ** The [sqlite3_mem_methods]
1650 ** structure is filled with the currently defined memory allocation routines.)^
1651 ** This option can be used to overload the default memory allocation
1652 ** routines with a wrapper that simulations memory allocation failure or
1653 ** tracks memory usage, for example. </dd>
1654 **
1655 ** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt>
1656 ** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of
1657 ** type int, interpreted as a boolean, which if true provides a hint to
1658 ** SQLite that it should avoid large memory allocations if possible.
1659 ** SQLite will run faster if it is free to make large memory allocations,
1660 ** but some application might prefer to run slower in exchange for
1661 ** guarantees about memory fragmentation that are possible if large
1662 ** allocations are avoided.  This hint is normally off.
1663 ** </dd>
1664 **
1665 ** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
1666 ** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int,
1667 ** interpreted as a boolean, which enables or disables the collection of
1668 ** memory allocation statistics. ^(When memory allocation statistics are
1669 ** disabled, the following SQLite interfaces become non-operational:
1670 **   <ul>
1671 **   <li> [sqlite3_memory_used()]
1672 **   <li> [sqlite3_memory_highwater()]
1673 **   <li> [sqlite3_soft_heap_limit64()]
1674 **   <li> [sqlite3_status64()]
1675 **   </ul>)^
1676 ** ^Memory allocation statistics are enabled by default unless SQLite is
1677 ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
1678 ** allocation statistics are disabled by default.
1679 ** </dd>
1680 **
1681 ** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
1682 ** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used.
1683 ** </dd>
1684 **
1685 ** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
1686 ** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool
1687 ** that SQLite can use for the database page cache with the default page
1688 ** cache implementation.
1689 ** This configuration option is a no-op if an application-define page
1690 ** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2].
1691 ** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to
1692 ** 8-byte aligned memory (pMem), the size of each page cache line (sz),
1693 ** and the number of cache lines (N).
1694 ** The sz argument should be the size of the largest database page
1695 ** (a power of two between 512 and 65536) plus some extra bytes for each
1696 ** page header.  ^The number of extra bytes needed by the page header
1697 ** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ].
1698 ** ^It is harmless, apart from the wasted memory,
1699 ** for the sz parameter to be larger than necessary.  The pMem
1700 ** argument must be either a NULL pointer or a pointer to an 8-byte
1701 ** aligned block of memory of at least sz*N bytes, otherwise
1702 ** subsequent behavior is undefined.
1703 ** ^When pMem is not NULL, SQLite will strive to use the memory provided
1704 ** to satisfy page cache needs, falling back to [sqlite3_malloc()] if
1705 ** a page cache line is larger than sz bytes or if all of the pMem buffer
1706 ** is exhausted.
1707 ** ^If pMem is NULL and N is non-zero, then each database connection
1708 ** does an initial bulk allocation for page cache memory
1709 ** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or
1710 ** of -1024*N bytes if N is negative, . ^If additional
1711 ** page cache memory is needed beyond what is provided by the initial
1712 ** allocation, then SQLite goes to [sqlite3_malloc()] separately for each
1713 ** additional cache line. </dd>
1714 **
1715 ** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
1716 ** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer
1717 ** that SQLite will use for all of its dynamic memory allocation needs
1718 ** beyond those provided for by [SQLITE_CONFIG_PAGECACHE].
1719 ** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled
1720 ** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns
1721 ** [SQLITE_ERROR] if invoked otherwise.
1722 ** ^There are three arguments to SQLITE_CONFIG_HEAP:
1723 ** An 8-byte aligned pointer to the memory,
1724 ** the number of bytes in the memory buffer, and the minimum allocation size.
1725 ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
1726 ** to using its default memory allocator (the system malloc() implementation),
1727 ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC].  ^If the
1728 ** memory pointer is not NULL then the alternative memory
1729 ** allocator is engaged to handle all of SQLites memory allocation needs.
1730 ** The first pointer (the memory pointer) must be aligned to an 8-byte
1731 ** boundary or subsequent behavior of SQLite will be undefined.
1732 ** The minimum allocation size is capped at 2**12. Reasonable values
1733 ** for the minimum allocation size are 2**5 through 2**8.</dd>
1734 **
1735 ** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
1736 ** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a
1737 ** pointer to an instance of the [sqlite3_mutex_methods] structure.
1738 ** The argument specifies alternative low-level mutex routines to be used
1739 ** in place the mutex routines built into SQLite.)^  ^SQLite makes a copy of
1740 ** the content of the [sqlite3_mutex_methods] structure before the call to
1741 ** [sqlite3_config()] returns. ^If SQLite is compiled with
1742 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1743 ** the entire mutexing subsystem is omitted from the build and hence calls to
1744 ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
1745 ** return [SQLITE_ERROR].</dd>
1746 **
1747 ** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
1748 ** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which
1749 ** is a pointer to an instance of the [sqlite3_mutex_methods] structure.  The
1750 ** [sqlite3_mutex_methods]
1751 ** structure is filled with the currently defined mutex routines.)^
1752 ** This option can be used to overload the default mutex allocation
1753 ** routines with a wrapper used to track mutex usage for performance
1754 ** profiling or testing, for example.   ^If SQLite is compiled with
1755 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1756 ** the entire mutexing subsystem is omitted from the build and hence calls to
1757 ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
1758 ** return [SQLITE_ERROR].</dd>
1759 **
1760 ** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
1761 ** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine
1762 ** the default size of lookaside memory on each [database connection].
1763 ** The first argument is the
1764 ** size of each lookaside buffer slot and the second is the number of
1765 ** slots allocated to each database connection.)^  ^(SQLITE_CONFIG_LOOKASIDE
1766 ** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
1767 ** option to [sqlite3_db_config()] can be used to change the lookaside
1768 ** configuration on individual connections.)^ </dd>
1769 **
1770 ** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
1771 ** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is
1772 ** a pointer to an [sqlite3_pcache_methods2] object.  This object specifies
1773 ** the interface to a custom page cache implementation.)^
1774 ** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd>
1775 **
1776 ** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
1777 ** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which
1778 ** is a pointer to an [sqlite3_pcache_methods2] object.  SQLite copies of
1779 ** the current page cache implementation into that object.)^ </dd>
1780 **
1781 ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
1782 ** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
1783 ** global [error log].
1784 ** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
1785 ** function with a call signature of void(*)(void*,int,const char*),
1786 ** and a pointer to void. ^If the function pointer is not NULL, it is
1787 ** invoked by [sqlite3_log()] to process each logging event.  ^If the
1788 ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
1789 ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
1790 ** passed through as the first parameter to the application-defined logger
1791 ** function whenever that function is invoked.  ^The second parameter to
1792 ** the logger function is a copy of the first parameter to the corresponding
1793 ** [sqlite3_log()] call and is intended to be a [result code] or an
1794 ** [extended result code].  ^The third parameter passed to the logger is
1795 ** log message after formatting via [sqlite3_snprintf()].
1796 ** The SQLite logging interface is not reentrant; the logger function
1797 ** supplied by the application must not invoke any SQLite interface.
1798 ** In a multi-threaded application, the application-defined logger
1799 ** function must be threadsafe. </dd>
1800 **
1801 ** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
1802 ** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int.
1803 ** If non-zero, then URI handling is globally enabled. If the parameter is zero,
1804 ** then URI handling is globally disabled.)^ ^If URI handling is globally
1805 ** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()],
1806 ** [sqlite3_open16()] or
1807 ** specified as part of [ATTACH] commands are interpreted as URIs, regardless
1808 ** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
1809 ** connection is opened. ^If it is globally disabled, filenames are
1810 ** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
1811 ** database connection is opened. ^(By default, URI handling is globally
1812 ** disabled. The default value may be changed by compiling with the
1813 ** [SQLITE_USE_URI] symbol defined.)^
1814 **
1815 ** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
1816 ** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer
1817 ** argument which is interpreted as a boolean in order to enable or disable
1818 ** the use of covering indices for full table scans in the query optimizer.
1819 ** ^The default setting is determined
1820 ** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
1821 ** if that compile-time option is omitted.
1822 ** The ability to disable the use of covering indices for full table scans
1823 ** is because some incorrectly coded legacy applications might malfunction
1824 ** when the optimization is enabled.  Providing the ability to
1825 ** disable the optimization allows the older, buggy application code to work
1826 ** without change even with newer versions of SQLite.
1827 **
1828 ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
1829 ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
1830 ** <dd> These options are obsolete and should not be used by new code.
1831 ** They are retained for backwards compatibility but are now no-ops.
1832 ** </dd>
1833 **
1834 ** [[SQLITE_CONFIG_SQLLOG]]
1835 ** <dt>SQLITE_CONFIG_SQLLOG
1836 ** <dd>This option is only available if sqlite is compiled with the
1837 ** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
1838 ** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
1839 ** The second should be of type (void*). The callback is invoked by the library
1840 ** in three separate circumstances, identified by the value passed as the
1841 ** fourth parameter. If the fourth parameter is 0, then the database connection
1842 ** passed as the second argument has just been opened. The third argument
1843 ** points to a buffer containing the name of the main database file. If the
1844 ** fourth parameter is 1, then the SQL statement that the third parameter
1845 ** points to has just been executed. Or, if the fourth parameter is 2, then
1846 ** the connection being passed as the second parameter is being closed. The
1847 ** third parameter is passed NULL In this case.  An example of using this
1848 ** configuration option can be seen in the "test_sqllog.c" source file in
1849 ** the canonical SQLite source tree.</dd>
1850 **
1851 ** [[SQLITE_CONFIG_MMAP_SIZE]]
1852 ** <dt>SQLITE_CONFIG_MMAP_SIZE
1853 ** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
1854 ** that are the default mmap size limit (the default setting for
1855 ** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
1856 ** ^The default setting can be overridden by each database connection using
1857 ** either the [PRAGMA mmap_size] command, or by using the
1858 ** [SQLITE_FCNTL_MMAP_SIZE] file control.  ^(The maximum allowed mmap size
1859 ** will be silently truncated if necessary so that it does not exceed the
1860 ** compile-time maximum mmap size set by the
1861 ** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
1862 ** ^If either argument to this option is negative, then that argument is
1863 ** changed to its compile-time default.
1864 **
1865 ** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
1866 ** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
1867 ** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is
1868 ** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro
1869 ** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
1870 ** that specifies the maximum size of the created heap.
1871 **
1872 ** [[SQLITE_CONFIG_PCACHE_HDRSZ]]
1873 ** <dt>SQLITE_CONFIG_PCACHE_HDRSZ
1874 ** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which
1875 ** is a pointer to an integer and writes into that integer the number of extra
1876 ** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE].
1877 ** The amount of extra space required can change depending on the compiler,
1878 ** target platform, and SQLite version.
1879 **
1880 ** [[SQLITE_CONFIG_PMASZ]]
1881 ** <dt>SQLITE_CONFIG_PMASZ
1882 ** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which
1883 ** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
1884 ** sorter to that integer.  The default minimum PMA Size is set by the
1885 ** [SQLITE_SORTER_PMASZ] compile-time option.  New threads are launched
1886 ** to help with sort operations when multithreaded sorting
1887 ** is enabled (using the [PRAGMA threads] command) and the amount of content
1888 ** to be sorted exceeds the page size times the minimum of the
1889 ** [PRAGMA cache_size] setting and this value.
1890 **
1891 ** [[SQLITE_CONFIG_STMTJRNL_SPILL]]
1892 ** <dt>SQLITE_CONFIG_STMTJRNL_SPILL
1893 ** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which
1894 ** becomes the [statement journal] spill-to-disk threshold.
1895 ** [Statement journals] are held in memory until their size (in bytes)
1896 ** exceeds this threshold, at which point they are written to disk.
1897 ** Or if the threshold is -1, statement journals are always held
1898 ** exclusively in memory.
1899 ** Since many statement journals never become large, setting the spill
1900 ** threshold to a value such as 64KiB can greatly reduce the amount of
1901 ** I/O required to support statement rollback.
1902 ** The default value for this setting is controlled by the
1903 ** [SQLITE_STMTJRNL_SPILL] compile-time option.
1904 ** </dl>
1905 */
1906 enum SQLITE_CONFIG_SINGLETHREAD = 1; /* nil */
1907 enum SQLITE_CONFIG_MULTITHREAD = 2; /* nil */
1908 enum SQLITE_CONFIG_SERIALIZED = 3; /* nil */
1909 enum SQLITE_CONFIG_MALLOC = 4; /* sqlite3_mem_methods* */
1910 enum SQLITE_CONFIG_GETMALLOC = 5; /* sqlite3_mem_methods* */
1911 enum SQLITE_CONFIG_SCRATCH = 6; /* No longer used */
1912 enum SQLITE_CONFIG_PAGECACHE = 7; /* void*, int sz, int N */
1913 enum SQLITE_CONFIG_HEAP = 8; /* void*, int nByte, int min */
1914 enum SQLITE_CONFIG_MEMSTATUS = 9; /* boolean */
1915 enum SQLITE_CONFIG_MUTEX = 10; /* sqlite3_mutex_methods* */
1916 enum SQLITE_CONFIG_GETMUTEX = 11; /* sqlite3_mutex_methods* */
1917 /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
1918 enum SQLITE_CONFIG_LOOKASIDE = 13; /* int int */
1919 enum SQLITE_CONFIG_PCACHE = 14; /* no-op */
1920 enum SQLITE_CONFIG_GETPCACHE = 15; /* no-op */
1921 enum SQLITE_CONFIG_LOG = 16; /* xFunc, void* */
1922 enum SQLITE_CONFIG_URI = 17; /* int */
1923 enum SQLITE_CONFIG_PCACHE2 = 18; /* sqlite3_pcache_methods2* */
1924 enum SQLITE_CONFIG_GETPCACHE2 = 19; /* sqlite3_pcache_methods2* */
1925 enum SQLITE_CONFIG_COVERING_INDEX_SCAN = 20; /* int */
1926 enum SQLITE_CONFIG_SQLLOG = 21; /* xSqllog, void* */
1927 enum SQLITE_CONFIG_MMAP_SIZE = 22; /* sqlite3_int64, sqlite3_int64 */
1928 enum SQLITE_CONFIG_WIN32_HEAPSIZE = 23; /* int nByte */
1929 enum SQLITE_CONFIG_PCACHE_HDRSZ = 24; /* int *psz */
1930 enum SQLITE_CONFIG_PMASZ = 25; /* unsigned int szPma */
1931 enum SQLITE_CONFIG_STMTJRNL_SPILL = 26; /* int nByte */
1932 enum SQLITE_CONFIG_SMALL_MALLOC = 27; /* boolean */
1933 
1934 /*
1935 ** CAPI3REF: Database Connection Configuration Options
1936 **
1937 ** These constants are the available integer configuration options that
1938 ** can be passed as the second argument to the [sqlite3_db_config()] interface.
1939 **
1940 ** New configuration options may be added in future releases of SQLite.
1941 ** Existing configuration options might be discontinued.  Applications
1942 ** should check the return code from [sqlite3_db_config()] to make sure that
1943 ** the call worked.  ^The [sqlite3_db_config()] interface will return a
1944 ** non-zero [error code] if a discontinued or unsupported configuration option
1945 ** is invoked.
1946 **
1947 ** <dl>
1948 ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
1949 ** <dd> ^This option takes three additional arguments that determine the
1950 ** [lookaside memory allocator] configuration for the [database connection].
1951 ** ^The first argument (the third parameter to [sqlite3_db_config()] is a
1952 ** pointer to a memory buffer to use for lookaside memory.
1953 ** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
1954 ** may be NULL in which case SQLite will allocate the
1955 ** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
1956 ** size of each lookaside buffer slot.  ^The third argument is the number of
1957 ** slots.  The size of the buffer in the first argument must be greater than
1958 ** or equal to the product of the second and third arguments.  The buffer
1959 ** must be aligned to an 8-byte boundary.  ^If the second argument to
1960 ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
1961 ** rounded down to the next smaller multiple of 8.  ^(The lookaside memory
1962 ** configuration for a database connection can only be changed when that
1963 ** connection is not currently using lookaside memory, or in other words
1964 ** when the "current value" returned by
1965 ** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
1966 ** Any attempt to change the lookaside memory configuration when lookaside
1967 ** memory is in use leaves the configuration unchanged and returns
1968 ** [SQLITE_BUSY].)^</dd>
1969 **
1970 ** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
1971 ** <dd> ^This option is used to enable or disable the enforcement of
1972 ** [foreign key constraints].  There should be two additional arguments.
1973 ** The first argument is an integer which is 0 to disable FK enforcement,
1974 ** positive to enable FK enforcement or negative to leave FK enforcement
1975 ** unchanged.  The second parameter is a pointer to an integer into which
1976 ** is written 0 or 1 to indicate whether FK enforcement is off or on
1977 ** following this call.  The second parameter may be a NULL pointer, in
1978 ** which case the FK enforcement setting is not reported back. </dd>
1979 **
1980 ** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
1981 ** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
1982 ** There should be two additional arguments.
1983 ** The first argument is an integer which is 0 to disable triggers,
1984 ** positive to enable triggers or negative to leave the setting unchanged.
1985 ** The second parameter is a pointer to an integer into which
1986 ** is written 0 or 1 to indicate whether triggers are disabled or enabled
1987 ** following this call.  The second parameter may be a NULL pointer, in
1988 ** which case the trigger setting is not reported back. </dd>
1989 **
1990 ** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt>
1991 ** <dd> ^This option is used to enable or disable the two-argument
1992 ** version of the [fts3_tokenizer()] function which is part of the
1993 ** [FTS3] full-text search engine extension.
1994 ** There should be two additional arguments.
1995 ** The first argument is an integer which is 0 to disable fts3_tokenizer() or
1996 ** positive to enable fts3_tokenizer() or negative to leave the setting
1997 ** unchanged.
1998 ** The second parameter is a pointer to an integer into which
1999 ** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled
2000 ** following this call.  The second parameter may be a NULL pointer, in
2001 ** which case the new setting is not reported back. </dd>
2002 **
2003 ** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt>
2004 ** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()]
2005 ** interface independently of the [load_extension()] SQL function.
2006 ** The [sqlite3_enable_load_extension()] API enables or disables both the
2007 ** C-API [sqlite3_load_extension()] and the SQL function [load_extension()].
2008 ** There should be two additional arguments.
2009 ** When the first argument to this interface is 1, then only the C-API is
2010 ** enabled and the SQL function remains disabled.  If the first argument to
2011 ** this interface is 0, then both the C-API and the SQL function are disabled.
2012 ** If the first argument is -1, then no changes are made to state of either the
2013 ** C-API or the SQL function.
2014 ** The second parameter is a pointer to an integer into which
2015 ** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface
2016 ** is disabled or enabled following this call.  The second parameter may
2017 ** be a NULL pointer, in which case the new setting is not reported back.
2018 ** </dd>
2019 **
2020 ** <dt>SQLITE_DBCONFIG_MAINDBNAME</dt>
2021 ** <dd> ^This option is used to change the name of the "main" database
2022 ** schema.  ^The sole argument is a pointer to a constant UTF8 string
2023 ** which will become the new schema name in place of "main".  ^SQLite
2024 ** does not make a copy of the new main schema name string, so the application
2025 ** must ensure that the argument passed into this DBCONFIG option is unchanged
2026 ** until after the database connection closes.
2027 ** </dd>
2028 **
2029 ** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt>
2030 ** <dd> Usually, when a database in wal mode is closed or detached from a
2031 ** database handle, SQLite checks if this will mean that there are now no
2032 ** connections at all to the database. If so, it performs a checkpoint
2033 ** operation before closing the connection. This option may be used to
2034 ** override this behaviour. The first parameter passed to this operation
2035 ** is an integer - non-zero to disable checkpoints-on-close, or zero (the
2036 ** default) to enable them. The second parameter is a pointer to an integer
2037 ** into which is written 0 or 1 to indicate whether checkpoints-on-close
2038 ** have been disabled - 0 if they are not disabled, 1 if they are.
2039 ** </dd>
2040 **
2041 ** <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt>
2042 ** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates
2043 ** the [query planner stability guarantee] (QPSG).  When the QPSG is active,
2044 ** a single SQL query statement will always use the same algorithm regardless
2045 ** of values of [bound parameters].)^ The QPSG disables some query optimizations
2046 ** that look at the values of bound parameters, which can make some queries
2047 ** slower.  But the QPSG has the advantage of more predictable behavior.  With
2048 ** the QPSG active, SQLite will always use the same query plan in the field as
2049 ** was used during testing in the lab.
2050 ** </dd>
2051 **
2052 ** </dl>
2053 */
2054 enum SQLITE_DBCONFIG_MAINDBNAME = 1000; /* const char* */
2055 enum SQLITE_DBCONFIG_LOOKASIDE = 1001; /* void* int int */
2056 enum SQLITE_DBCONFIG_ENABLE_FKEY = 1002; /* int int* */
2057 enum SQLITE_DBCONFIG_ENABLE_TRIGGER = 1003; /* int int* */
2058 enum SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER = 1004; /* int int* */
2059 enum SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION = 1005; /* int int* */
2060 enum SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE = 1006; /* int int* */
2061 enum SQLITE_DBCONFIG_ENABLE_QPSG = 1007; /* int int* */
2062 
2063 /*
2064 ** CAPI3REF: Enable Or Disable Extended Result Codes
2065 ** METHOD: sqlite3
2066 **
2067 ** ^The sqlite3_extended_result_codes() routine enables or disables the
2068 ** [extended result codes] feature of SQLite. ^The extended result
2069 ** codes are disabled by default for historical compatibility.
2070 */
2071 int sqlite3_extended_result_codes(sqlite3*, int onoff);
2072 
2073 /*
2074 ** CAPI3REF: Last Insert Rowid
2075 ** METHOD: sqlite3
2076 **
2077 ** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
2078 ** has a unique 64-bit signed
2079 ** integer key called the [ROWID | "rowid"]. ^The rowid is always available
2080 ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
2081 ** names are not also used by explicitly declared columns. ^If
2082 ** the table has a column of type [INTEGER PRIMARY KEY] then that column
2083 ** is another alias for the rowid.
2084 **
2085 ** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of
2086 ** the most recent successful [INSERT] into a rowid table or [virtual table]
2087 ** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not
2088 ** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred
2089 ** on the database connection D, then sqlite3_last_insert_rowid(D) returns
2090 ** zero.
2091 **
2092 ** As well as being set automatically as rows are inserted into database
2093 ** tables, the value returned by this function may be set explicitly by
2094 ** [sqlite3_set_last_insert_rowid()]
2095 **
2096 ** Some virtual table implementations may INSERT rows into rowid tables as
2097 ** part of committing a transaction (e.g. to flush data accumulated in memory
2098 ** to disk). In this case subsequent calls to this function return the rowid
2099 ** associated with these internal INSERT operations, which leads to
2100 ** unintuitive results. Virtual table implementations that do write to rowid
2101 ** tables in this way can avoid this problem by restoring the original
2102 ** rowid value using [sqlite3_set_last_insert_rowid()] before returning
2103 ** control to the user.
2104 **
2105 ** ^(If an [INSERT] occurs within a trigger then this routine will
2106 ** return the [rowid] of the inserted row as long as the trigger is
2107 ** running. Once the trigger program ends, the value returned
2108 ** by this routine reverts to what it was before the trigger was fired.)^
2109 **
2110 ** ^An [INSERT] that fails due to a constraint violation is not a
2111 ** successful [INSERT] and does not change the value returned by this
2112 ** routine.  ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
2113 ** and INSERT OR ABORT make no changes to the return value of this
2114 ** routine when their insertion fails.  ^(When INSERT OR REPLACE
2115 ** encounters a constraint violation, it does not fail.  The
2116 ** INSERT continues to completion after deleting rows that caused
2117 ** the constraint problem so INSERT OR REPLACE will always change
2118 ** the return value of this interface.)^
2119 **
2120 ** ^For the purposes of this routine, an [INSERT] is considered to
2121 ** be successful even if it is subsequently rolled back.
2122 **
2123 ** This function is accessible to SQL statements via the
2124 ** [last_insert_rowid() SQL function].
2125 **
2126 ** If a separate thread performs a new [INSERT] on the same
2127 ** database connection while the [sqlite3_last_insert_rowid()]
2128 ** function is running and thus changes the last insert [rowid],
2129 ** then the value returned by [sqlite3_last_insert_rowid()] is
2130 ** unpredictable and might not equal either the old or the new
2131 ** last insert [rowid].
2132 */
2133 sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
2134 
2135 /*
2136 ** CAPI3REF: Set the Last Insert Rowid value.
2137 ** METHOD: sqlite3
2138 **
2139 ** The sqlite3_set_last_insert_rowid(D, R) method allows the application to
2140 ** set the value returned by calling sqlite3_last_insert_rowid(D) to R
2141 ** without inserting a row into the database.
2142 */
2143 void sqlite3_set_last_insert_rowid(sqlite3*, sqlite3_int64);
2144 
2145 /*
2146 ** CAPI3REF: Count The Number Of Rows Modified
2147 ** METHOD: sqlite3
2148 **
2149 ** ^This function returns the number of rows modified, inserted or
2150 ** deleted by the most recently completed INSERT, UPDATE or DELETE
2151 ** statement on the database connection specified by the only parameter.
2152 ** ^Executing any other type of SQL statement does not modify the value
2153 ** returned by this function.
2154 **
2155 ** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are
2156 ** considered - auxiliary changes caused by [CREATE TRIGGER | triggers],
2157 ** [foreign key actions] or [REPLACE] constraint resolution are not counted.
2158 **
2159 ** Changes to a view that are intercepted by
2160 ** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value
2161 ** returned by sqlite3_changes() immediately after an INSERT, UPDATE or
2162 ** DELETE statement run on a view is always zero. Only changes made to real
2163 ** tables are counted.
2164 **
2165 ** Things are more complicated if the sqlite3_changes() function is
2166 ** executed while a trigger program is running. This may happen if the
2167 ** program uses the [changes() SQL function], or if some other callback
2168 ** function invokes sqlite3_changes() directly. Essentially:
2169 **
2170 ** <ul>
2171 **   <li> ^(Before entering a trigger program the value returned by
2172 **        sqlite3_changes() function is saved. After the trigger program
2173 **        has finished, the original value is restored.)^
2174 **
2175 **   <li> ^(Within a trigger program each INSERT, UPDATE and DELETE
2176 **        statement sets the value returned by sqlite3_changes()
2177 **        upon completion as normal. Of course, this value will not include
2178 **        any changes performed by sub-triggers, as the sqlite3_changes()
2179 **        value will be saved and restored after each sub-trigger has run.)^
2180 ** </ul>
2181 **
2182 ** ^This means that if the changes() SQL function (or similar) is used
2183 ** by the first INSERT, UPDATE or DELETE statement within a trigger, it
2184 ** returns the value as set when the calling statement began executing.
2185 ** ^If it is used by the second or subsequent such statement within a trigger
2186 ** program, the value returned reflects the number of rows modified by the
2187 ** previous INSERT, UPDATE or DELETE statement within the same trigger.
2188 **
2189 ** See also the [sqlite3_total_changes()] interface, the
2190 ** [count_changes pragma], and the [changes() SQL function].
2191 **
2192 ** If a separate thread makes changes on the same database connection
2193 ** while [sqlite3_changes()] is running then the value returned
2194 ** is unpredictable and not meaningful.
2195 */
2196 int sqlite3_changes(sqlite3*);
2197 
2198 /*
2199 ** CAPI3REF: Total Number Of Rows Modified
2200 ** METHOD: sqlite3
2201 **
2202 ** ^This function returns the total number of rows inserted, modified or
2203 ** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed
2204 ** since the database connection was opened, including those executed as
2205 ** part of trigger programs. ^Executing any other type of SQL statement
2206 ** does not affect the value returned by sqlite3_total_changes().
2207 **
2208 ** ^Changes made as part of [foreign key actions] are included in the
2209 ** count, but those made as part of REPLACE constraint resolution are
2210 ** not. ^Changes to a view that are intercepted by INSTEAD OF triggers
2211 ** are not counted.
2212 **
2213 ** See also the [sqlite3_changes()] interface, the
2214 ** [count_changes pragma], and the [total_changes() SQL function].
2215 **
2216 ** If a separate thread makes changes on the same database connection
2217 ** while [sqlite3_total_changes()] is running then the value
2218 ** returned is unpredictable and not meaningful.
2219 */
2220 int sqlite3_total_changes(sqlite3*);
2221 
2222 /*
2223 ** CAPI3REF: Interrupt A Long-Running Query
2224 ** METHOD: sqlite3
2225 **
2226 ** ^This function causes any pending database operation to abort and
2227 ** return at its earliest opportunity. This routine is typically
2228 ** called in response to a user action such as pressing "Cancel"
2229 ** or Ctrl-C where the user wants a long query operation to halt
2230 ** immediately.
2231 **
2232 ** ^It is safe to call this routine from a thread different from the
2233 ** thread that is currently running the database operation.  But it
2234 ** is not safe to call this routine with a [database connection] that
2235 ** is closed or might close before sqlite3_interrupt() returns.
2236 **
2237 ** ^If an SQL operation is very nearly finished at the time when
2238 ** sqlite3_interrupt() is called, then it might not have an opportunity
2239 ** to be interrupted and might continue to completion.
2240 **
2241 ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
2242 ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
2243 ** that is inside an explicit transaction, then the entire transaction
2244 ** will be rolled back automatically.
2245 **
2246 ** ^The sqlite3_interrupt(D) call is in effect until all currently running
2247 ** SQL statements on [database connection] D complete.  ^Any new SQL statements
2248 ** that are started after the sqlite3_interrupt() call and before the
2249 ** running statements reaches zero are interrupted as if they had been
2250 ** running prior to the sqlite3_interrupt() call.  ^New SQL statements
2251 ** that are started after the running statement count reaches zero are
2252 ** not effected by the sqlite3_interrupt().
2253 ** ^A call to sqlite3_interrupt(D) that occurs when there are no running
2254 ** SQL statements is a no-op and has no effect on SQL statements
2255 ** that are started after the sqlite3_interrupt() call returns.
2256 */
2257 void sqlite3_interrupt(sqlite3*);
2258 
2259 /*
2260 ** CAPI3REF: Determine If An SQL Statement Is Complete
2261 **
2262 ** These routines are useful during command-line input to determine if the
2263 ** currently entered text seems to form a complete SQL statement or
2264 ** if additional input is needed before sending the text into
2265 ** SQLite for parsing.  ^These routines return 1 if the input string
2266 ** appears to be a complete SQL statement.  ^A statement is judged to be
2267 ** complete if it ends with a semicolon token and is not a prefix of a
2268 ** well-formed CREATE TRIGGER statement.  ^Semicolons that are embedded within
2269 ** string literals or quoted identifier names or comments are not
2270 ** independent tokens (they are part of the token in which they are
2271 ** embedded) and thus do not count as a statement terminator.  ^Whitespace
2272 ** and comments that follow the final semicolon are ignored.
2273 **
2274 ** ^These routines return 0 if the statement is incomplete.  ^If a
2275 ** memory allocation fails, then SQLITE_NOMEM is returned.
2276 **
2277 ** ^These routines do not parse the SQL statements thus
2278 ** will not detect syntactically incorrect SQL.
2279 **
2280 ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
2281 ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
2282 ** automatically by sqlite3_complete16().  If that initialization fails,
2283 ** then the return value from sqlite3_complete16() will be non-zero
2284 ** regardless of whether or not the input SQL is complete.)^
2285 **
2286 ** The input to [sqlite3_complete()] must be a zero-terminated
2287 ** UTF-8 string.
2288 **
2289 ** The input to [sqlite3_complete16()] must be a zero-terminated
2290 ** UTF-16 string in native byte order.
2291 */
2292 int sqlite3_complete(const(char)* sql);
2293 int sqlite3_complete16(const(void)* sql);
2294 
2295 /*
2296 ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
2297 ** KEYWORDS: {busy-handler callback} {busy handler}
2298 ** METHOD: sqlite3
2299 **
2300 ** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
2301 ** that might be invoked with argument P whenever
2302 ** an attempt is made to access a database table associated with
2303 ** [database connection] D when another thread
2304 ** or process has the table locked.
2305 ** The sqlite3_busy_handler() interface is used to implement
2306 ** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
2307 **
2308 ** ^If the busy callback is NULL, then [SQLITE_BUSY]
2309 ** is returned immediately upon encountering the lock.  ^If the busy callback
2310 ** is not NULL, then the callback might be invoked with two arguments.
2311 **
2312 ** ^The first argument to the busy handler is a copy of the void* pointer which
2313 ** is the third argument to sqlite3_busy_handler().  ^The second argument to
2314 ** the busy handler callback is the number of times that the busy handler has
2315 ** been invoked previously for the same locking event.  ^If the
2316 ** busy callback returns 0, then no additional attempts are made to
2317 ** access the database and [SQLITE_BUSY] is returned
2318 ** to the application.
2319 ** ^If the callback returns non-zero, then another attempt
2320 ** is made to access the database and the cycle repeats.
2321 **
2322 ** The presence of a busy handler does not guarantee that it will be invoked
2323 ** when there is lock contention. ^If SQLite determines that invoking the busy
2324 ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
2325 ** to the application instead of invoking the
2326 ** busy handler.
2327 ** Consider a scenario where one process is holding a read lock that
2328 ** it is trying to promote to a reserved lock and
2329 ** a second process is holding a reserved lock that it is trying
2330 ** to promote to an exclusive lock.  The first process cannot proceed
2331 ** because it is blocked by the second and the second process cannot
2332 ** proceed because it is blocked by the first.  If both processes
2333 ** invoke the busy handlers, neither will make any progress.  Therefore,
2334 ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
2335 ** will induce the first process to release its read lock and allow
2336 ** the second process to proceed.
2337 **
2338 ** ^The default busy callback is NULL.
2339 **
2340 ** ^(There can only be a single busy handler defined for each
2341 ** [database connection].  Setting a new busy handler clears any
2342 ** previously set handler.)^  ^Note that calling [sqlite3_busy_timeout()]
2343 ** or evaluating [PRAGMA busy_timeout=N] will change the
2344 ** busy handler and thus clear any previously set busy handler.
2345 **
2346 ** The busy callback should not take any actions which modify the
2347 ** database connection that invoked the busy handler.  In other words,
2348 ** the busy handler is not reentrant.  Any such actions
2349 ** result in undefined behavior.
2350 **
2351 ** A busy handler must not close the database connection
2352 ** or [prepared statement] that invoked the busy handler.
2353 */
2354 int sqlite3_busy_handler(sqlite3*, int function(void*, int), void*);
2355 
2356 /*
2357 ** CAPI3REF: Set A Busy Timeout
2358 ** METHOD: sqlite3
2359 **
2360 ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
2361 ** for a specified amount of time when a table is locked.  ^The handler
2362 ** will sleep multiple times until at least "ms" milliseconds of sleeping
2363 ** have accumulated.  ^After at least "ms" milliseconds of sleeping,
2364 ** the handler returns 0 which causes [sqlite3_step()] to return
2365 ** [SQLITE_BUSY].
2366 **
2367 ** ^Calling this routine with an argument less than or equal to zero
2368 ** turns off all busy handlers.
2369 **
2370 ** ^(There can only be a single busy handler for a particular
2371 ** [database connection] at any given moment.  If another busy handler
2372 ** was defined  (using [sqlite3_busy_handler()]) prior to calling
2373 ** this routine, that other busy handler is cleared.)^
2374 **
2375 ** See also:  [PRAGMA busy_timeout]
2376 */
2377 int sqlite3_busy_timeout(sqlite3*, int ms);
2378 
2379 /*
2380 ** CAPI3REF: Convenience Routines For Running Queries
2381 ** METHOD: sqlite3
2382 **
2383 ** This is a legacy interface that is preserved for backwards compatibility.
2384 ** Use of this interface is not recommended.
2385 **
2386 ** Definition: A <b>result table</b> is memory data structure created by the
2387 ** [sqlite3_get_table()] interface.  A result table records the
2388 ** complete query results from one or more queries.
2389 **
2390 ** The table conceptually has a number of rows and columns.  But
2391 ** these numbers are not part of the result table itself.  These
2392 ** numbers are obtained separately.  Let N be the number of rows
2393 ** and M be the number of columns.
2394 **
2395 ** A result table is an array of pointers to zero-terminated UTF-8 strings.
2396 ** There are (N+1)*M elements in the array.  The first M pointers point
2397 ** to zero-terminated strings that  contain the names of the columns.
2398 ** The remaining entries all point to query results.  NULL values result
2399 ** in NULL pointers.  All other values are in their UTF-8 zero-terminated
2400 ** string representation as returned by [sqlite3_column_text()].
2401 **
2402 ** A result table might consist of one or more memory allocations.
2403 ** It is not safe to pass a result table directly to [sqlite3_free()].
2404 ** A result table should be deallocated using [sqlite3_free_table()].
2405 **
2406 ** ^(As an example of the result table format, suppose a query result
2407 ** is as follows:
2408 **
2409 ** <blockquote><pre>
2410 **        Name        | Age
2411 **        -----------------------
2412 **        Alice       | 43
2413 **        Bob         | 28
2414 **        Cindy       | 21
2415 ** </pre></blockquote>
2416 **
2417 ** There are two column (M==2) and three rows (N==3).  Thus the
2418 ** result table has 8 entries.  Suppose the result table is stored
2419 ** in an array names azResult.  Then azResult holds this content:
2420 **
2421 ** <blockquote><pre>
2422 **        azResult&#91;0] = "Name";
2423 **        azResult&#91;1] = "Age";
2424 **        azResult&#91;2] = "Alice";
2425 **        azResult&#91;3] = "43";
2426 **        azResult&#91;4] = "Bob";
2427 **        azResult&#91;5] = "28";
2428 **        azResult&#91;6] = "Cindy";
2429 **        azResult&#91;7] = "21";
2430 ** </pre></blockquote>)^
2431 **
2432 ** ^The sqlite3_get_table() function evaluates one or more
2433 ** semicolon-separated SQL statements in the zero-terminated UTF-8
2434 ** string of its 2nd parameter and returns a result table to the
2435 ** pointer given in its 3rd parameter.
2436 **
2437 ** After the application has finished with the result from sqlite3_get_table(),
2438 ** it must pass the result table pointer to sqlite3_free_table() in order to
2439 ** release the memory that was malloced.  Because of the way the
2440 ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
2441 ** function must not try to call [sqlite3_free()] directly.  Only
2442 ** [sqlite3_free_table()] is able to release the memory properly and safely.
2443 **
2444 ** The sqlite3_get_table() interface is implemented as a wrapper around
2445 ** [sqlite3_exec()].  The sqlite3_get_table() routine does not have access
2446 ** to any internal data structures of SQLite.  It uses only the public
2447 ** interface defined here.  As a consequence, errors that occur in the
2448 ** wrapper layer outside of the internal [sqlite3_exec()] call are not
2449 ** reflected in subsequent calls to [sqlite3_errcode()] or
2450 ** [sqlite3_errmsg()].
2451 */
2452 /* An open database */
2453 /* SQL to be evaluated */
2454 /* Results of the query */
2455 /* Number of result rows written here */
2456 /* Number of result columns written here */
2457 /* Error msg written here */
2458 int sqlite3_get_table(
2459     sqlite3* db,
2460     const(char)* zSql,
2461     char*** pazResult,
2462     int* pnRow,
2463     int* pnColumn,
2464     char** pzErrmsg);
2465 void sqlite3_free_table(char** result);
2466 
2467 /*
2468 ** CAPI3REF: Formatted String Printing Functions
2469 **
2470 ** These routines are work-alikes of the "printf()" family of functions
2471 ** from the standard C library.
2472 ** These routines understand most of the common K&R formatting options,
2473 ** plus some additional non-standard formats, detailed below.
2474 ** Note that some of the more obscure formatting options from recent
2475 ** C-library standards are omitted from this implementation.
2476 **
2477 ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
2478 ** results into memory obtained from [sqlite3_malloc()].
2479 ** The strings returned by these two routines should be
2480 ** released by [sqlite3_free()].  ^Both routines return a
2481 ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
2482 ** memory to hold the resulting string.
2483 **
2484 ** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
2485 ** the standard C library.  The result is written into the
2486 ** buffer supplied as the second parameter whose size is given by
2487 ** the first parameter. Note that the order of the
2488 ** first two parameters is reversed from snprintf().)^  This is an
2489 ** historical accident that cannot be fixed without breaking
2490 ** backwards compatibility.  ^(Note also that sqlite3_snprintf()
2491 ** returns a pointer to its buffer instead of the number of
2492 ** characters actually written into the buffer.)^  We admit that
2493 ** the number of characters written would be a more useful return
2494 ** value but we cannot change the implementation of sqlite3_snprintf()
2495 ** now without breaking compatibility.
2496 **
2497 ** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
2498 ** guarantees that the buffer is always zero-terminated.  ^The first
2499 ** parameter "n" is the total size of the buffer, including space for
2500 ** the zero terminator.  So the longest string that can be completely
2501 ** written will be n-1 characters.
2502 **
2503 ** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
2504 **
2505 ** These routines all implement some additional formatting
2506 ** options that are useful for constructing SQL statements.
2507 ** All of the usual printf() formatting options apply.  In addition, there
2508 ** is are "%q", "%Q", "%w" and "%z" options.
2509 **
2510 ** ^(The %q option works like %s in that it substitutes a nul-terminated
2511 ** string from the argument list.  But %q also doubles every '\'' character.
2512 ** %q is designed for use inside a string literal.)^  By doubling each '\''
2513 ** character it escapes that character and allows it to be inserted into
2514 ** the string.
2515 **
2516 ** For example, assume the string variable zText contains text as follows:
2517 **
2518 ** <blockquote><pre>
2519 **  char *zText = "It's a happy day!";
2520 ** </pre></blockquote>
2521 **
2522 ** One can use this text in an SQL statement as follows:
2523 **
2524 ** <blockquote><pre>
2525 **  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
2526 **  sqlite3_exec(db, zSQL, 0, 0, 0);
2527 **  sqlite3_free(zSQL);
2528 ** </pre></blockquote>
2529 **
2530 ** Because the %q format string is used, the '\'' character in zText
2531 ** is escaped and the SQL generated is as follows:
2532 **
2533 ** <blockquote><pre>
2534 **  INSERT INTO table1 VALUES('It''s a happy day!')
2535 ** </pre></blockquote>
2536 **
2537 ** This is correct.  Had we used %s instead of %q, the generated SQL
2538 ** would have looked like this:
2539 **
2540 ** <blockquote><pre>
2541 **  INSERT INTO table1 VALUES('It's a happy day!');
2542 ** </pre></blockquote>
2543 **
2544 ** This second example is an SQL syntax error.  As a general rule you should
2545 ** always use %q instead of %s when inserting text into a string literal.
2546 **
2547 ** ^(The %Q option works like %q except it also adds single quotes around
2548 ** the outside of the total string.  Additionally, if the parameter in the
2549 ** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
2550 ** single quotes).)^  So, for example, one could say:
2551 **
2552 ** <blockquote><pre>
2553 **  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
2554 **  sqlite3_exec(db, zSQL, 0, 0, 0);
2555 **  sqlite3_free(zSQL);
2556 ** </pre></blockquote>
2557 **
2558 ** The code above will render a correct SQL statement in the zSQL
2559 ** variable even if the zText variable is a NULL pointer.
2560 **
2561 ** ^(The "%w" formatting option is like "%q" except that it expects to
2562 ** be contained within double-quotes instead of single quotes, and it
2563 ** escapes the double-quote character instead of the single-quote
2564 ** character.)^  The "%w" formatting option is intended for safely inserting
2565 ** table and column names into a constructed SQL statement.
2566 **
2567 ** ^(The "%z" formatting option works like "%s" but with the
2568 ** addition that after the string has been read and copied into
2569 ** the result, [sqlite3_free()] is called on the input string.)^
2570 */
2571 char* sqlite3_mprintf(const(char)*, ...);
2572 char* sqlite3_vmprintf(const(char)*, va_list);
2573 char* sqlite3_snprintf(int, char*, const(char)*, ...);
2574 char* sqlite3_vsnprintf(int, char*, const(char)*, va_list);
2575 
2576 /*
2577 ** CAPI3REF: Memory Allocation Subsystem
2578 **
2579 ** The SQLite core uses these three routines for all of its own
2580 ** internal memory allocation needs. "Core" in the previous sentence
2581 ** does not include operating-system specific VFS implementation.  The
2582 ** Windows VFS uses native malloc() and free() for some operations.
2583 **
2584 ** ^The sqlite3_malloc() routine returns a pointer to a block
2585 ** of memory at least N bytes in length, where N is the parameter.
2586 ** ^If sqlite3_malloc() is unable to obtain sufficient free
2587 ** memory, it returns a NULL pointer.  ^If the parameter N to
2588 ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
2589 ** a NULL pointer.
2590 **
2591 ** ^The sqlite3_malloc64(N) routine works just like
2592 ** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead
2593 ** of a signed 32-bit integer.
2594 **
2595 ** ^Calling sqlite3_free() with a pointer previously returned
2596 ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
2597 ** that it might be reused.  ^The sqlite3_free() routine is
2598 ** a no-op if is called with a NULL pointer.  Passing a NULL pointer
2599 ** to sqlite3_free() is harmless.  After being freed, memory
2600 ** should neither be read nor written.  Even reading previously freed
2601 ** memory might result in a segmentation fault or other severe error.
2602 ** Memory corruption, a segmentation fault, or other severe error
2603 ** might result if sqlite3_free() is called with a non-NULL pointer that
2604 ** was not obtained from sqlite3_malloc() or sqlite3_realloc().
2605 **
2606 ** ^The sqlite3_realloc(X,N) interface attempts to resize a
2607 ** prior memory allocation X to be at least N bytes.
2608 ** ^If the X parameter to sqlite3_realloc(X,N)
2609 ** is a NULL pointer then its behavior is identical to calling
2610 ** sqlite3_malloc(N).
2611 ** ^If the N parameter to sqlite3_realloc(X,N) is zero or
2612 ** negative then the behavior is exactly the same as calling
2613 ** sqlite3_free(X).
2614 ** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation
2615 ** of at least N bytes in size or NULL if insufficient memory is available.
2616 ** ^If M is the size of the prior allocation, then min(N,M) bytes
2617 ** of the prior allocation are copied into the beginning of buffer returned
2618 ** by sqlite3_realloc(X,N) and the prior allocation is freed.
2619 ** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the
2620 ** prior allocation is not freed.
2621 **
2622 ** ^The sqlite3_realloc64(X,N) interfaces works the same as
2623 ** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead
2624 ** of a 32-bit signed integer.
2625 **
2626 ** ^If X is a memory allocation previously obtained from sqlite3_malloc(),
2627 ** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then
2628 ** sqlite3_msize(X) returns the size of that memory allocation in bytes.
2629 ** ^The value returned by sqlite3_msize(X) might be larger than the number
2630 ** of bytes requested when X was allocated.  ^If X is a NULL pointer then
2631 ** sqlite3_msize(X) returns zero.  If X points to something that is not
2632 ** the beginning of memory allocation, or if it points to a formerly
2633 ** valid memory allocation that has now been freed, then the behavior
2634 ** of sqlite3_msize(X) is undefined and possibly harmful.
2635 **
2636 ** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(),
2637 ** sqlite3_malloc64(), and sqlite3_realloc64()
2638 ** is always aligned to at least an 8 byte boundary, or to a
2639 ** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
2640 ** option is used.
2641 **
2642 ** In SQLite version 3.5.0 and 3.5.1, it was possible to define
2643 ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
2644 ** implementation of these routines to be omitted.  That capability
2645 ** is no longer provided.  Only built-in memory allocators can be used.
2646 **
2647 ** Prior to SQLite version 3.7.10, the Windows OS interface layer called
2648 ** the system malloc() and free() directly when converting
2649 ** filenames between the UTF-8 encoding used by SQLite
2650 ** and whatever filename encoding is used by the particular Windows
2651 ** installation.  Memory allocation errors were detected, but
2652 ** they were reported back as [SQLITE_CANTOPEN] or
2653 ** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
2654 **
2655 ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
2656 ** must be either NULL or else pointers obtained from a prior
2657 ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
2658 ** not yet been released.
2659 **
2660 ** The application must not read or write any part of
2661 ** a block of memory after it has been released using
2662 ** [sqlite3_free()] or [sqlite3_realloc()].
2663 */
2664 void* sqlite3_malloc(int);
2665 void* sqlite3_malloc64(sqlite3_uint64);
2666 void* sqlite3_realloc(void*, int);
2667 void* sqlite3_realloc64(void*, sqlite3_uint64);
2668 void sqlite3_free(void*);
2669 sqlite3_uint64 sqlite3_msize(void*);
2670 
2671 /*
2672 ** CAPI3REF: Memory Allocator Statistics
2673 **
2674 ** SQLite provides these two interfaces for reporting on the status
2675 ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
2676 ** routines, which form the built-in memory allocation subsystem.
2677 **
2678 ** ^The [sqlite3_memory_used()] routine returns the number of bytes
2679 ** of memory currently outstanding (malloced but not freed).
2680 ** ^The [sqlite3_memory_highwater()] routine returns the maximum
2681 ** value of [sqlite3_memory_used()] since the high-water mark
2682 ** was last reset.  ^The values returned by [sqlite3_memory_used()] and
2683 ** [sqlite3_memory_highwater()] include any overhead
2684 ** added by SQLite in its implementation of [sqlite3_malloc()],
2685 ** but not overhead added by the any underlying system library
2686 ** routines that [sqlite3_malloc()] may call.
2687 **
2688 ** ^The memory high-water mark is reset to the current value of
2689 ** [sqlite3_memory_used()] if and only if the parameter to
2690 ** [sqlite3_memory_highwater()] is true.  ^The value returned
2691 ** by [sqlite3_memory_highwater(1)] is the high-water mark
2692 ** prior to the reset.
2693 */
2694 sqlite3_int64 sqlite3_memory_used();
2695 sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
2696 
2697 /*
2698 ** CAPI3REF: Pseudo-Random Number Generator
2699 **
2700 ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
2701 ** select random [ROWID | ROWIDs] when inserting new records into a table that
2702 ** already uses the largest possible [ROWID].  The PRNG is also used for
2703 ** the build-in random() and randomblob() SQL functions.  This interface allows
2704 ** applications to access the same PRNG for other purposes.
2705 **
2706 ** ^A call to this routine stores N bytes of randomness into buffer P.
2707 ** ^The P parameter can be a NULL pointer.
2708 **
2709 ** ^If this routine has not been previously called or if the previous
2710 ** call had N less than one or a NULL pointer for P, then the PRNG is
2711 ** seeded using randomness obtained from the xRandomness method of
2712 ** the default [sqlite3_vfs] object.
2713 ** ^If the previous call to this routine had an N of 1 or more and a
2714 ** non-NULL P then the pseudo-randomness is generated
2715 ** internally and without recourse to the [sqlite3_vfs] xRandomness
2716 ** method.
2717 */
2718 void sqlite3_randomness(int N, void* P);
2719 
2720 /*
2721 ** CAPI3REF: Compile-Time Authorization Callbacks
2722 ** METHOD: sqlite3
2723 ** KEYWORDS: {authorizer callback}
2724 **
2725 ** ^This routine registers an authorizer callback with a particular
2726 ** [database connection], supplied in the first argument.
2727 ** ^The authorizer callback is invoked as SQL statements are being compiled
2728 ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
2729 ** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()],
2730 ** and [sqlite3_prepare16_v3()].  ^At various
2731 ** points during the compilation process, as logic is being created
2732 ** to perform various actions, the authorizer callback is invoked to
2733 ** see if those actions are allowed.  ^The authorizer callback should
2734 ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
2735 ** specific action but allow the SQL statement to continue to be
2736 ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
2737 ** rejected with an error.  ^If the authorizer callback returns
2738 ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
2739 ** then the [sqlite3_prepare_v2()] or equivalent call that triggered
2740 ** the authorizer will fail with an error message.
2741 **
2742 ** When the callback returns [SQLITE_OK], that means the operation
2743 ** requested is ok.  ^When the callback returns [SQLITE_DENY], the
2744 ** [sqlite3_prepare_v2()] or equivalent call that triggered the
2745 ** authorizer will fail with an error message explaining that
2746 ** access is denied.
2747 **
2748 ** ^The first parameter to the authorizer callback is a copy of the third
2749 ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
2750 ** to the callback is an integer [SQLITE_COPY | action code] that specifies
2751 ** the particular action to be authorized. ^The third through sixth parameters
2752 ** to the callback are either NULL pointers or zero-terminated strings
2753 ** that contain additional details about the action to be authorized.
2754 ** Applications must always be prepared to encounter a NULL pointer in any
2755 ** of the third through the sixth parameters of the authorization callback.
2756 **
2757 ** ^If the action code is [SQLITE_READ]
2758 ** and the callback returns [SQLITE_IGNORE] then the
2759 ** [prepared statement] statement is constructed to substitute
2760 ** a NULL value in place of the table column that would have
2761 ** been read if [SQLITE_OK] had been returned.  The [SQLITE_IGNORE]
2762 ** return can be used to deny an untrusted user access to individual
2763 ** columns of a table.
2764 ** ^When a table is referenced by a [SELECT] but no column values are
2765 ** extracted from that table (for example in a query like
2766 ** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback
2767 ** is invoked once for that table with a column name that is an empty string.
2768 ** ^If the action code is [SQLITE_DELETE] and the callback returns
2769 ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
2770 ** [truncate optimization] is disabled and all rows are deleted individually.
2771 **
2772 ** An authorizer is used when [sqlite3_prepare | preparing]
2773 ** SQL statements from an untrusted source, to ensure that the SQL statements
2774 ** do not try to access data they are not allowed to see, or that they do not
2775 ** try to execute malicious statements that damage the database.  For
2776 ** example, an application may allow a user to enter arbitrary
2777 ** SQL queries for evaluation by a database.  But the application does
2778 ** not want the user to be able to make arbitrary changes to the
2779 ** database.  An authorizer could then be put in place while the
2780 ** user-entered SQL is being [sqlite3_prepare | prepared] that
2781 ** disallows everything except [SELECT] statements.
2782 **
2783 ** Applications that need to process SQL from untrusted sources
2784 ** might also consider lowering resource limits using [sqlite3_limit()]
2785 ** and limiting database size using the [max_page_count] [PRAGMA]
2786 ** in addition to using an authorizer.
2787 **
2788 ** ^(Only a single authorizer can be in place on a database connection
2789 ** at a time.  Each call to sqlite3_set_authorizer overrides the
2790 ** previous call.)^  ^Disable the authorizer by installing a NULL callback.
2791 ** The authorizer is disabled by default.
2792 **
2793 ** The authorizer callback must not do anything that will modify
2794 ** the database connection that invoked the authorizer callback.
2795 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
2796 ** database connections for the meaning of "modify" in this paragraph.
2797 **
2798 ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
2799 ** statement might be re-prepared during [sqlite3_step()] due to a
2800 ** schema change.  Hence, the application should ensure that the
2801 ** correct authorizer callback remains in place during the [sqlite3_step()].
2802 **
2803 ** ^Note that the authorizer callback is invoked only during
2804 ** [sqlite3_prepare()] or its variants.  Authorization is not
2805 ** performed during statement evaluation in [sqlite3_step()], unless
2806 ** as stated in the previous paragraph, sqlite3_step() invokes
2807 ** sqlite3_prepare_v2() to reprepare a statement after a schema change.
2808 */
2809 int sqlite3_set_authorizer(
2810     sqlite3*,
2811     int function(void*, int, const(char)*, const(char)*, const(char)*, const(char)*) xAuth,
2812     void* pUserData);
2813 
2814 /*
2815 ** CAPI3REF: Authorizer Return Codes
2816 **
2817 ** The [sqlite3_set_authorizer | authorizer callback function] must
2818 ** return either [SQLITE_OK] or one of these two constants in order
2819 ** to signal SQLite whether or not the action is permitted.  See the
2820 ** [sqlite3_set_authorizer | authorizer documentation] for additional
2821 ** information.
2822 **
2823 ** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
2824 ** returned from the [sqlite3_vtab_on_conflict()] interface.
2825 */
2826 enum SQLITE_DENY = 1; /* Abort the SQL statement with an error */
2827 enum SQLITE_IGNORE = 2; /* Don't allow access, but don't generate an error */
2828 
2829 /*
2830 ** CAPI3REF: Authorizer Action Codes
2831 **
2832 ** The [sqlite3_set_authorizer()] interface registers a callback function
2833 ** that is invoked to authorize certain SQL statement actions.  The
2834 ** second parameter to the callback is an integer code that specifies
2835 ** what action is being authorized.  These are the integer action codes that
2836 ** the authorizer callback may be passed.
2837 **
2838 ** These action code values signify what kind of operation is to be
2839 ** authorized.  The 3rd and 4th parameters to the authorization
2840 ** callback function will be parameters or NULL depending on which of these
2841 ** codes is used as the second parameter.  ^(The 5th parameter to the
2842 ** authorizer callback is the name of the database ("main", "temp",
2843 ** etc.) if applicable.)^  ^The 6th parameter to the authorizer callback
2844 ** is the name of the inner-most trigger or view that is responsible for
2845 ** the access attempt or NULL if this access attempt is directly from
2846 ** top-level SQL code.
2847 */
2848 /******************************************* 3rd ************ 4th ***********/
2849 enum SQLITE_CREATE_INDEX = 1; /* Index Name      Table Name      */
2850 enum SQLITE_CREATE_TABLE = 2; /* Table Name      NULL            */
2851 enum SQLITE_CREATE_TEMP_INDEX = 3; /* Index Name      Table Name      */
2852 enum SQLITE_CREATE_TEMP_TABLE = 4; /* Table Name      NULL            */
2853 enum SQLITE_CREATE_TEMP_TRIGGER = 5; /* Trigger Name    Table Name      */
2854 enum SQLITE_CREATE_TEMP_VIEW = 6; /* View Name       NULL            */
2855 enum SQLITE_CREATE_TRIGGER = 7; /* Trigger Name    Table Name      */
2856 enum SQLITE_CREATE_VIEW = 8; /* View Name       NULL            */
2857 enum SQLITE_DELETE = 9; /* Table Name      NULL            */
2858 enum SQLITE_DROP_INDEX = 10; /* Index Name      Table Name      */
2859 enum SQLITE_DROP_TABLE = 11; /* Table Name      NULL            */
2860 enum SQLITE_DROP_TEMP_INDEX = 12; /* Index Name      Table Name      */
2861 enum SQLITE_DROP_TEMP_TABLE = 13; /* Table Name      NULL            */
2862 enum SQLITE_DROP_TEMP_TRIGGER = 14; /* Trigger Name    Table Name      */
2863 enum SQLITE_DROP_TEMP_VIEW = 15; /* View Name       NULL            */
2864 enum SQLITE_DROP_TRIGGER = 16; /* Trigger Name    Table Name      */
2865 enum SQLITE_DROP_VIEW = 17; /* View Name       NULL            */
2866 enum SQLITE_INSERT = 18; /* Table Name      NULL            */
2867 enum SQLITE_PRAGMA = 19; /* Pragma Name     1st arg or NULL */
2868 enum SQLITE_READ = 20; /* Table Name      Column Name     */
2869 enum SQLITE_SELECT = 21; /* NULL            NULL            */
2870 enum SQLITE_TRANSACTION = 22; /* Operation       NULL            */
2871 enum SQLITE_UPDATE = 23; /* Table Name      Column Name     */
2872 enum SQLITE_ATTACH = 24; /* Filename        NULL            */
2873 enum SQLITE_DETACH = 25; /* Database Name   NULL            */
2874 enum SQLITE_ALTER_TABLE = 26; /* Database Name   Table Name      */
2875 enum SQLITE_REINDEX = 27; /* Index Name      NULL            */
2876 enum SQLITE_ANALYZE = 28; /* Table Name      NULL            */
2877 enum SQLITE_CREATE_VTABLE = 29; /* Table Name      Module Name     */
2878 enum SQLITE_DROP_VTABLE = 30; /* Table Name      Module Name     */
2879 enum SQLITE_FUNCTION = 31; /* NULL            Function Name   */
2880 enum SQLITE_SAVEPOINT = 32; /* Operation       Savepoint Name  */
2881 enum SQLITE_COPY = 0; /* No longer used */
2882 enum SQLITE_RECURSIVE = 33; /* NULL            NULL            */
2883 
2884 /*
2885 ** CAPI3REF: Tracing And Profiling Functions
2886 ** METHOD: sqlite3
2887 **
2888 ** These routines are deprecated. Use the [sqlite3_trace_v2()] interface
2889 ** instead of the routines described here.
2890 **
2891 ** These routines register callback functions that can be used for
2892 ** tracing and profiling the execution of SQL statements.
2893 **
2894 ** ^The callback function registered by sqlite3_trace() is invoked at
2895 ** various times when an SQL statement is being run by [sqlite3_step()].
2896 ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
2897 ** SQL statement text as the statement first begins executing.
2898 ** ^(Additional sqlite3_trace() callbacks might occur
2899 ** as each triggered subprogram is entered.  The callbacks for triggers
2900 ** contain a UTF-8 SQL comment that identifies the trigger.)^
2901 **
2902 ** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
2903 ** the length of [bound parameter] expansion in the output of sqlite3_trace().
2904 **
2905 ** ^The callback function registered by sqlite3_profile() is invoked
2906 ** as each SQL statement finishes.  ^The profile callback contains
2907 ** the original statement text and an estimate of wall-clock time
2908 ** of how long that statement took to run.  ^The profile callback
2909 ** time is in units of nanoseconds, however the current implementation
2910 ** is only capable of millisecond resolution so the six least significant
2911 ** digits in the time are meaningless.  Future versions of SQLite
2912 ** might provide greater resolution on the profiler callback.  The
2913 ** sqlite3_profile() function is considered experimental and is
2914 ** subject to change in future versions of SQLite.
2915 */
2916 void* sqlite3_trace(sqlite3*, void function(void*, const(char)*) xTrace, void*);
2917 void* sqlite3_profile(
2918     sqlite3*,
2919     void function(void*, const(char)*, sqlite3_uint64) xProfile,
2920     void*);
2921 
2922 /*
2923 ** CAPI3REF: SQL Trace Event Codes
2924 ** KEYWORDS: SQLITE_TRACE
2925 **
2926 ** These constants identify classes of events that can be monitored
2927 ** using the [sqlite3_trace_v2()] tracing logic.  The third argument
2928 ** to [sqlite3_trace_v2()] is an OR-ed combination of one or more of
2929 ** the following constants.  ^The first argument to the trace callback
2930 ** is one of the following constants.
2931 **
2932 ** New tracing constants may be added in future releases.
2933 **
2934 ** ^A trace callback has four arguments: xCallback(T,C,P,X).
2935 ** ^The T argument is one of the integer type codes above.
2936 ** ^The C argument is a copy of the context pointer passed in as the
2937 ** fourth argument to [sqlite3_trace_v2()].
2938 ** The P and X arguments are pointers whose meanings depend on T.
2939 **
2940 ** <dl>
2941 ** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt>
2942 ** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement
2943 ** first begins running and possibly at other times during the
2944 ** execution of the prepared statement, such as at the start of each
2945 ** trigger subprogram. ^The P argument is a pointer to the
2946 ** [prepared statement]. ^The X argument is a pointer to a string which
2947 ** is the unexpanded SQL text of the prepared statement or an SQL comment
2948 ** that indicates the invocation of a trigger.  ^The callback can compute
2949 ** the same text that would have been returned by the legacy [sqlite3_trace()]
2950 ** interface by using the X argument when X begins with "--" and invoking
2951 ** [sqlite3_expanded_sql(P)] otherwise.
2952 **
2953 ** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt>
2954 ** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same
2955 ** information as is provided by the [sqlite3_profile()] callback.
2956 ** ^The P argument is a pointer to the [prepared statement] and the
2957 ** X argument points to a 64-bit integer which is the estimated of
2958 ** the number of nanosecond that the prepared statement took to run.
2959 ** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes.
2960 **
2961 ** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt>
2962 ** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared
2963 ** statement generates a single row of result.
2964 ** ^The P argument is a pointer to the [prepared statement] and the
2965 ** X argument is unused.
2966 **
2967 ** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt>
2968 ** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database
2969 ** connection closes.
2970 ** ^The P argument is a pointer to the [database connection] object
2971 ** and the X argument is unused.
2972 ** </dl>
2973 */
2974 enum SQLITE_TRACE_STMT = 0x01;
2975 enum SQLITE_TRACE_PROFILE = 0x02;
2976 enum SQLITE_TRACE_ROW = 0x04;
2977 enum SQLITE_TRACE_CLOSE = 0x08;
2978 
2979 /*
2980 ** CAPI3REF: SQL Trace Hook
2981 ** METHOD: sqlite3
2982 **
2983 ** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback
2984 ** function X against [database connection] D, using property mask M
2985 ** and context pointer P.  ^If the X callback is
2986 ** NULL or if the M mask is zero, then tracing is disabled.  The
2987 ** M argument should be the bitwise OR-ed combination of
2988 ** zero or more [SQLITE_TRACE] constants.
2989 **
2990 ** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides
2991 ** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2().
2992 **
2993 ** ^The X callback is invoked whenever any of the events identified by
2994 ** mask M occur.  ^The integer return value from the callback is currently
2995 ** ignored, though this may change in future releases.  Callback
2996 ** implementations should return zero to ensure future compatibility.
2997 **
2998 ** ^A trace callback is invoked with four arguments: callback(T,C,P,X).
2999 ** ^The T argument is one of the [SQLITE_TRACE]
3000 ** constants to indicate why the callback was invoked.
3001 ** ^The C argument is a copy of the context pointer.
3002 ** The P and X arguments are pointers whose meanings depend on T.
3003 **
3004 ** The sqlite3_trace_v2() interface is intended to replace the legacy
3005 ** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which
3006 ** are deprecated.
3007 */
3008 int sqlite3_trace_v2(
3009     sqlite3*,
3010     uint uMask,
3011     int function(uint, void*, void*, void*) xCallback,
3012     void* pCtx);
3013 
3014 /*
3015 ** CAPI3REF: Query Progress Callbacks
3016 ** METHOD: sqlite3
3017 **
3018 ** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
3019 ** function X to be invoked periodically during long running calls to
3020 ** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
3021 ** database connection D.  An example use for this
3022 ** interface is to keep a GUI updated during a large query.
3023 **
3024 ** ^The parameter P is passed through as the only parameter to the
3025 ** callback function X.  ^The parameter N is the approximate number of
3026 ** [virtual machine instructions] that are evaluated between successive
3027 ** invocations of the callback X.  ^If N is less than one then the progress
3028 ** handler is disabled.
3029 **
3030 ** ^Only a single progress handler may be defined at one time per
3031 ** [database connection]; setting a new progress handler cancels the
3032 ** old one.  ^Setting parameter X to NULL disables the progress handler.
3033 ** ^The progress handler is also disabled by setting N to a value less
3034 ** than 1.
3035 **
3036 ** ^If the progress callback returns non-zero, the operation is
3037 ** interrupted.  This feature can be used to implement a
3038 ** "Cancel" button on a GUI progress dialog box.
3039 **
3040 ** The progress handler callback must not do anything that will modify
3041 ** the database connection that invoked the progress handler.
3042 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3043 ** database connections for the meaning of "modify" in this paragraph.
3044 **
3045 */
3046 void sqlite3_progress_handler(sqlite3*, int, int function(void*), void*);
3047 
3048 /*
3049 ** CAPI3REF: Opening A New Database Connection
3050 ** CONSTRUCTOR: sqlite3
3051 **
3052 ** ^These routines open an SQLite database file as specified by the
3053 ** filename argument. ^The filename argument is interpreted as UTF-8 for
3054 ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
3055 ** order for sqlite3_open16(). ^(A [database connection] handle is usually
3056 ** returned in *ppDb, even if an error occurs.  The only exception is that
3057 ** if SQLite is unable to allocate memory to hold the [sqlite3] object,
3058 ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
3059 ** object.)^ ^(If the database is opened (and/or created) successfully, then
3060 ** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.)^ ^The
3061 ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
3062 ** an English language description of the error following a failure of any
3063 ** of the sqlite3_open() routines.
3064 **
3065 ** ^The default encoding will be UTF-8 for databases created using
3066 ** sqlite3_open() or sqlite3_open_v2().  ^The default encoding for databases
3067 ** created using sqlite3_open16() will be UTF-16 in the native byte order.
3068 **
3069 ** Whether or not an error occurs when it is opened, resources
3070 ** associated with the [database connection] handle should be released by
3071 ** passing it to [sqlite3_close()] when it is no longer required.
3072 **
3073 ** The sqlite3_open_v2() interface works like sqlite3_open()
3074 ** except that it accepts two additional parameters for additional control
3075 ** over the new database connection.  ^(The flags parameter to
3076 ** sqlite3_open_v2() can take one of
3077 ** the following three values, optionally combined with the
3078 ** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
3079 ** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^
3080 **
3081 ** <dl>
3082 ** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
3083 ** <dd>The database is opened in read-only mode.  If the database does not
3084 ** already exist, an error is returned.</dd>)^
3085 **
3086 ** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
3087 ** <dd>The database is opened for reading and writing if possible, or reading
3088 ** only if the file is write protected by the operating system.  In either
3089 ** case the database must already exist, otherwise an error is returned.</dd>)^
3090 **
3091 ** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
3092 ** <dd>The database is opened for reading and writing, and is created if
3093 ** it does not already exist. This is the behavior that is always used for
3094 ** sqlite3_open() and sqlite3_open16().</dd>)^
3095 ** </dl>
3096 **
3097 ** If the 3rd parameter to sqlite3_open_v2() is not one of the
3098 ** combinations shown above optionally combined with other
3099 ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
3100 ** then the behavior is undefined.
3101 **
3102 ** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
3103 ** opens in the multi-thread [threading mode] as long as the single-thread
3104 ** mode has not been set at compile-time or start-time.  ^If the
3105 ** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
3106 ** in the serialized [threading mode] unless single-thread was
3107 ** previously selected at compile-time or start-time.
3108 ** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
3109 ** eligible to use [shared cache mode], regardless of whether or not shared
3110 ** cache is enabled using [sqlite3_enable_shared_cache()].  ^The
3111 ** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
3112 ** participate in [shared cache mode] even if it is enabled.
3113 **
3114 ** ^The fourth parameter to sqlite3_open_v2() is the name of the
3115 ** [sqlite3_vfs] object that defines the operating system interface that
3116 ** the new database connection should use.  ^If the fourth parameter is
3117 ** a NULL pointer then the default [sqlite3_vfs] object is used.
3118 **
3119 ** ^If the filename is ":memory:", then a private, temporary in-memory database
3120 ** is created for the connection.  ^This in-memory database will vanish when
3121 ** the database connection is closed.  Future versions of SQLite might
3122 ** make use of additional special filenames that begin with the ":" character.
3123 ** It is recommended that when a database filename actually does begin with
3124 ** a ":" character you should prefix the filename with a pathname such as
3125 ** "./" to avoid ambiguity.
3126 **
3127 ** ^If the filename is an empty string, then a private, temporary
3128 ** on-disk database will be created.  ^This private database will be
3129 ** automatically deleted as soon as the database connection is closed.
3130 **
3131 ** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
3132 **
3133 ** ^If [URI filename] interpretation is enabled, and the filename argument
3134 ** begins with "file:", then the filename is interpreted as a URI. ^URI
3135 ** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
3136 ** set in the third argument to sqlite3_open_v2(), or if it has
3137 ** been enabled globally using the [SQLITE_CONFIG_URI] option with the
3138 ** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
3139 ** URI filename interpretation is turned off
3140 ** by default, but future releases of SQLite might enable URI filename
3141 ** interpretation by default.  See "[URI filenames]" for additional
3142 ** information.
3143 **
3144 ** URI filenames are parsed according to RFC 3986. ^If the URI contains an
3145 ** authority, then it must be either an empty string or the string
3146 ** "localhost". ^If the authority is not an empty string or "localhost", an
3147 ** error is returned to the caller. ^The fragment component of a URI, if
3148 ** present, is ignored.
3149 **
3150 ** ^SQLite uses the path component of the URI as the name of the disk file
3151 ** which contains the database. ^If the path begins with a '/' character,
3152 ** then it is interpreted as an absolute path. ^If the path does not begin
3153 ** with a '/' (meaning that the authority section is omitted from the URI)
3154 ** then the path is interpreted as a relative path.
3155 ** ^(On windows, the first component of an absolute path
3156 ** is a drive specification (e.g. "C:").)^
3157 **
3158 ** [[core URI query parameters]]
3159 ** The query component of a URI may contain parameters that are interpreted
3160 ** either by SQLite itself, or by a [VFS | custom VFS implementation].
3161 ** SQLite and its built-in [VFSes] interpret the
3162 ** following query parameters:
3163 **
3164 ** <ul>
3165 **   <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
3166 **     a VFS object that provides the operating system interface that should
3167 **     be used to access the database file on disk. ^If this option is set to
3168 **     an empty string the default VFS object is used. ^Specifying an unknown
3169 **     VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
3170 **     present, then the VFS specified by the option takes precedence over
3171 **     the value passed as the fourth parameter to sqlite3_open_v2().
3172 **
3173 **   <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
3174 **     "rwc", or "memory". Attempting to set it to any other value is
3175 **     an error)^.
3176 **     ^If "ro" is specified, then the database is opened for read-only
3177 **     access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
3178 **     third argument to sqlite3_open_v2(). ^If the mode option is set to
3179 **     "rw", then the database is opened for read-write (but not create)
3180 **     access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
3181 **     been set. ^Value "rwc" is equivalent to setting both
3182 **     SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE.  ^If the mode option is
3183 **     set to "memory" then a pure [in-memory database] that never reads
3184 **     or writes from disk is used. ^It is an error to specify a value for
3185 **     the mode parameter that is less restrictive than that specified by
3186 **     the flags passed in the third parameter to sqlite3_open_v2().
3187 **
3188 **   <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
3189 **     "private". ^Setting it to "shared" is equivalent to setting the
3190 **     SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
3191 **     sqlite3_open_v2(). ^Setting the cache parameter to "private" is
3192 **     equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
3193 **     ^If sqlite3_open_v2() is used and the "cache" parameter is present in
3194 **     a URI filename, its value overrides any behavior requested by setting
3195 **     SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
3196 **
3197 **  <li> <b>psow</b>: ^The psow parameter indicates whether or not the
3198 **     [powersafe overwrite] property does or does not apply to the
3199 **     storage media on which the database file resides.
3200 **
3201 **  <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
3202 **     which if set disables file locking in rollback journal modes.  This
3203 **     is useful for accessing a database on a filesystem that does not
3204 **     support locking.  Caution:  Database corruption might result if two
3205 **     or more processes write to the same database and any one of those
3206 **     processes uses nolock=1.
3207 **
3208 **  <li> <b>immutable</b>: ^The immutable parameter is a boolean query
3209 **     parameter that indicates that the database file is stored on
3210 **     read-only media.  ^When immutable is set, SQLite assumes that the
3211 **     database file cannot be changed, even by a process with higher
3212 **     privilege, and so the database is opened read-only and all locking
3213 **     and change detection is disabled.  Caution: Setting the immutable
3214 **     property on a database file that does in fact change can result
3215 **     in incorrect query results and/or [SQLITE_CORRUPT] errors.
3216 **     See also: [SQLITE_IOCAP_IMMUTABLE].
3217 **
3218 ** </ul>
3219 **
3220 ** ^Specifying an unknown parameter in the query component of a URI is not an
3221 ** error.  Future versions of SQLite might understand additional query
3222 ** parameters.  See "[query parameters with special meaning to SQLite]" for
3223 ** additional information.
3224 **
3225 ** [[URI filename examples]] <h3>URI filename examples</h3>
3226 **
3227 ** <table border="1" align=center cellpadding=5>
3228 ** <tr><th> URI filenames <th> Results
3229 ** <tr><td> file:data.db <td>
3230 **          Open the file "data.db" in the current directory.
3231 ** <tr><td> file:/home/fred/data.db<br>
3232 **          file:///home/fred/data.db <br>
3233 **          file://localhost/home/fred/data.db <br> <td>
3234 **          Open the database file "/home/fred/data.db".
3235 ** <tr><td> file://darkstar/home/fred/data.db <td>
3236 **          An error. "darkstar" is not a recognized authority.
3237 ** <tr><td style="white-space:nowrap">
3238 **          file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
3239 **     <td> Windows only: Open the file "data.db" on fred's desktop on drive
3240 **          C:. Note that the %20 escaping in this example is not strictly
3241 **          necessary - space characters can be used literally
3242 **          in URI filenames.
3243 ** <tr><td> file:data.db?mode=ro&cache=private <td>
3244 **          Open file "data.db" in the current directory for read-only access.
3245 **          Regardless of whether or not shared-cache mode is enabled by
3246 **          default, use a private cache.
3247 ** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>
3248 **          Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
3249 **          that uses dot-files in place of posix advisory locking.
3250 ** <tr><td> file:data.db?mode=readonly <td>
3251 **          An error. "readonly" is not a valid option for the "mode" parameter.
3252 ** </table>
3253 **
3254 ** ^URI hexadecimal escape sequences (%HH) are supported within the path and
3255 ** query components of a URI. A hexadecimal escape sequence consists of a
3256 ** percent sign - "%" - followed by exactly two hexadecimal digits
3257 ** specifying an octet value. ^Before the path or query components of a
3258 ** URI filename are interpreted, they are encoded using UTF-8 and all
3259 ** hexadecimal escape sequences replaced by a single byte containing the
3260 ** corresponding octet. If this process generates an invalid UTF-8 encoding,
3261 ** the results are undefined.
3262 **
3263 ** <b>Note to Windows users:</b>  The encoding used for the filename argument
3264 ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
3265 ** codepage is currently defined.  Filenames containing international
3266 ** characters must be converted to UTF-8 prior to passing them into
3267 ** sqlite3_open() or sqlite3_open_v2().
3268 **
3269 ** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
3270 ** prior to calling sqlite3_open() or sqlite3_open_v2().  Otherwise, various
3271 ** features that require the use of temporary files may fail.
3272 **
3273 ** See also: [sqlite3_temp_directory]
3274 */
3275 /* Database filename (UTF-8) */
3276 /* OUT: SQLite db handle */
3277 int sqlite3_open(const(char)* filename, sqlite3** ppDb);
3278 
3279 /* Database filename (UTF-16) */
3280 /* OUT: SQLite db handle */
3281 int sqlite3_open16(const(void)* filename, sqlite3** ppDb);
3282 
3283 /* Database filename (UTF-8) */
3284 /* OUT: SQLite db handle */
3285 /* Flags */
3286 /* Name of VFS module to use */
3287 int sqlite3_open_v2(
3288     const(char)* filename,
3289     sqlite3** ppDb,
3290     int flags,
3291     const(char)* zVfs);
3292 
3293 /*
3294 ** CAPI3REF: Obtain Values For URI Parameters
3295 **
3296 ** These are utility routines, useful to VFS implementations, that check
3297 ** to see if a database file was a URI that contained a specific query
3298 ** parameter, and if so obtains the value of that query parameter.
3299 **
3300 ** If F is the database filename pointer passed into the xOpen() method of
3301 ** a VFS implementation when the flags parameter to xOpen() has one or
3302 ** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and
3303 ** P is the name of the query parameter, then
3304 ** sqlite3_uri_parameter(F,P) returns the value of the P
3305 ** parameter if it exists or a NULL pointer if P does not appear as a
3306 ** query parameter on F.  If P is a query parameter of F
3307 ** has no explicit value, then sqlite3_uri_parameter(F,P) returns
3308 ** a pointer to an empty string.
3309 **
3310 ** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
3311 ** parameter and returns true (1) or false (0) according to the value
3312 ** of P.  The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
3313 ** value of query parameter P is one of "yes", "true", or "on" in any
3314 ** case or if the value begins with a non-zero number.  The
3315 ** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
3316 ** query parameter P is one of "no", "false", or "off" in any case or
3317 ** if the value begins with a numeric zero.  If P is not a query
3318 ** parameter on F or if the value of P is does not match any of the
3319 ** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
3320 **
3321 ** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
3322 ** 64-bit signed integer and returns that integer, or D if P does not
3323 ** exist.  If the value of P is something other than an integer, then
3324 ** zero is returned.
3325 **
3326 ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
3327 ** sqlite3_uri_boolean(F,P,B) returns B.  If F is not a NULL pointer and
3328 ** is not a database file pathname pointer that SQLite passed into the xOpen
3329 ** VFS method, then the behavior of this routine is undefined and probably
3330 ** undesirable.
3331 */
3332 const(char)* sqlite3_uri_parameter(const(char)* zFilename, const(char)* zParam);
3333 int sqlite3_uri_boolean(const(char)* zFile, const(char)* zParam, int bDefault);
3334 sqlite3_int64 sqlite3_uri_int64(const(char)*, const(char)*, sqlite3_int64);
3335 
3336 /*
3337 ** CAPI3REF: Error Codes And Messages
3338 ** METHOD: sqlite3
3339 **
3340 ** ^If the most recent sqlite3_* API call associated with
3341 ** [database connection] D failed, then the sqlite3_errcode(D) interface
3342 ** returns the numeric [result code] or [extended result code] for that
3343 ** API call.
3344 ** If the most recent API call was successful,
3345 ** then the return value from sqlite3_errcode() is undefined.
3346 ** ^The sqlite3_extended_errcode()
3347 ** interface is the same except that it always returns the
3348 ** [extended result code] even when extended result codes are
3349 ** disabled.
3350 **
3351 ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
3352 ** text that describes the error, as either UTF-8 or UTF-16 respectively.
3353 ** ^(Memory to hold the error message string is managed internally.
3354 ** The application does not need to worry about freeing the result.
3355 ** However, the error string might be overwritten or deallocated by
3356 ** subsequent calls to other SQLite interface functions.)^
3357 **
3358 ** ^The sqlite3_errstr() interface returns the English-language text
3359 ** that describes the [result code], as UTF-8.
3360 ** ^(Memory to hold the error message string is managed internally
3361 ** and must not be freed by the application)^.
3362 **
3363 ** When the serialized [threading mode] is in use, it might be the
3364 ** case that a second error occurs on a separate thread in between
3365 ** the time of the first error and the call to these interfaces.
3366 ** When that happens, the second error will be reported since these
3367 ** interfaces always report the most recent result.  To avoid
3368 ** this, each thread can obtain exclusive use of the [database connection] D
3369 ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
3370 ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
3371 ** all calls to the interfaces listed here are completed.
3372 **
3373 ** If an interface fails with SQLITE_MISUSE, that means the interface
3374 ** was invoked incorrectly by the application.  In that case, the
3375 ** error code and message may or may not be set.
3376 */
3377 int sqlite3_errcode(sqlite3* db);
3378 int sqlite3_extended_errcode(sqlite3* db);
3379 const(char)* sqlite3_errmsg(sqlite3*);
3380 const(void)* sqlite3_errmsg16(sqlite3*);
3381 const(char)* sqlite3_errstr(int);
3382 
3383 /*
3384 ** CAPI3REF: Prepared Statement Object
3385 ** KEYWORDS: {prepared statement} {prepared statements}
3386 **
3387 ** An instance of this object represents a single SQL statement that
3388 ** has been compiled into binary form and is ready to be evaluated.
3389 **
3390 ** Think of each SQL statement as a separate computer program.  The
3391 ** original SQL text is source code.  A prepared statement object
3392 ** is the compiled object code.  All SQL must be converted into a
3393 ** prepared statement before it can be run.
3394 **
3395 ** The life-cycle of a prepared statement object usually goes like this:
3396 **
3397 ** <ol>
3398 ** <li> Create the prepared statement object using [sqlite3_prepare_v2()].
3399 ** <li> Bind values to [parameters] using the sqlite3_bind_*()
3400 **      interfaces.
3401 ** <li> Run the SQL by calling [sqlite3_step()] one or more times.
3402 ** <li> Reset the prepared statement using [sqlite3_reset()] then go back
3403 **      to step 2.  Do this zero or more times.
3404 ** <li> Destroy the object using [sqlite3_finalize()].
3405 ** </ol>
3406 */
3407 struct sqlite3_stmt;
3408 
3409 /*
3410 ** CAPI3REF: Run-time Limits
3411 ** METHOD: sqlite3
3412 **
3413 ** ^(This interface allows the size of various constructs to be limited
3414 ** on a connection by connection basis.  The first parameter is the
3415 ** [database connection] whose limit is to be set or queried.  The
3416 ** second parameter is one of the [limit categories] that define a
3417 ** class of constructs to be size limited.  The third parameter is the
3418 ** new limit for that construct.)^
3419 **
3420 ** ^If the new limit is a negative number, the limit is unchanged.
3421 ** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
3422 ** [limits | hard upper bound]
3423 ** set at compile-time by a C preprocessor macro called
3424 ** [limits | SQLITE_MAX_<i>NAME</i>].
3425 ** (The "_LIMIT_" in the name is changed to "_MAX_".))^
3426 ** ^Attempts to increase a limit above its hard upper bound are
3427 ** silently truncated to the hard upper bound.
3428 **
3429 ** ^Regardless of whether or not the limit was changed, the
3430 ** [sqlite3_limit()] interface returns the prior value of the limit.
3431 ** ^Hence, to find the current value of a limit without changing it,
3432 ** simply invoke this interface with the third parameter set to -1.
3433 **
3434 ** Run-time limits are intended for use in applications that manage
3435 ** both their own internal database and also databases that are controlled
3436 ** by untrusted external sources.  An example application might be a
3437 ** web browser that has its own databases for storing history and
3438 ** separate databases controlled by JavaScript applications downloaded
3439 ** off the Internet.  The internal databases can be given the
3440 ** large, default limits.  Databases managed by external sources can
3441 ** be given much smaller limits designed to prevent a denial of service
3442 ** attack.  Developers might also want to use the [sqlite3_set_authorizer()]
3443 ** interface to further control untrusted SQL.  The size of the database
3444 ** created by an untrusted script can be contained using the
3445 ** [max_page_count] [PRAGMA].
3446 **
3447 ** New run-time limit categories may be added in future releases.
3448 */
3449 int sqlite3_limit(sqlite3*, int id, int newVal);
3450 
3451 /*
3452 ** CAPI3REF: Run-Time Limit Categories
3453 ** KEYWORDS: {limit category} {*limit categories}
3454 **
3455 ** These constants define various performance limits
3456 ** that can be lowered at run-time using [sqlite3_limit()].
3457 ** The synopsis of the meanings of the various limits is shown below.
3458 ** Additional information is available at [limits | Limits in SQLite].
3459 **
3460 ** <dl>
3461 ** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
3462 ** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
3463 **
3464 ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
3465 ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
3466 **
3467 ** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
3468 ** <dd>The maximum number of columns in a table definition or in the
3469 ** result set of a [SELECT] or the maximum number of columns in an index
3470 ** or in an ORDER BY or GROUP BY clause.</dd>)^
3471 **
3472 ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
3473 ** <dd>The maximum depth of the parse tree on any expression.</dd>)^
3474 **
3475 ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
3476 ** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
3477 **
3478 ** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
3479 ** <dd>The maximum number of instructions in a virtual machine program
3480 ** used to implement an SQL statement.  If [sqlite3_prepare_v2()] or
3481 ** the equivalent tries to allocate space for more than this many opcodes
3482 ** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^
3483 **
3484 ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
3485 ** <dd>The maximum number of arguments on a function.</dd>)^
3486 **
3487 ** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
3488 ** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
3489 **
3490 ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
3491 ** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
3492 ** <dd>The maximum length of the pattern argument to the [LIKE] or
3493 ** [GLOB] operators.</dd>)^
3494 **
3495 ** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
3496 ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
3497 ** <dd>The maximum index number of any [parameter] in an SQL statement.)^
3498 **
3499 ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
3500 ** <dd>The maximum depth of recursion for triggers.</dd>)^
3501 **
3502 ** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt>
3503 ** <dd>The maximum number of auxiliary worker threads that a single
3504 ** [prepared statement] may start.</dd>)^
3505 ** </dl>
3506 */
3507 enum SQLITE_LIMIT_LENGTH = 0;
3508 enum SQLITE_LIMIT_SQL_LENGTH = 1;
3509 enum SQLITE_LIMIT_COLUMN = 2;
3510 enum SQLITE_LIMIT_EXPR_DEPTH = 3;
3511 enum SQLITE_LIMIT_COMPOUND_SELECT = 4;
3512 enum SQLITE_LIMIT_VDBE_OP = 5;
3513 enum SQLITE_LIMIT_FUNCTION_ARG = 6;
3514 enum SQLITE_LIMIT_ATTACHED = 7;
3515 enum SQLITE_LIMIT_LIKE_PATTERN_LENGTH = 8;
3516 enum SQLITE_LIMIT_VARIABLE_NUMBER = 9;
3517 enum SQLITE_LIMIT_TRIGGER_DEPTH = 10;
3518 enum SQLITE_LIMIT_WORKER_THREADS = 11;
3519 
3520 /*
3521 ** CAPI3REF: Prepare Flags
3522 **
3523 ** These constants define various flags that can be passed into
3524 ** "prepFlags" parameter of the [sqlite3_prepare_v3()] and
3525 ** [sqlite3_prepare16_v3()] interfaces.
3526 **
3527 ** New flags may be added in future releases of SQLite.
3528 **
3529 ** <dl>
3530 ** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt>
3531 ** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner
3532 ** that the prepared statement will be retained for a long time and
3533 ** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()]
3534 ** and [sqlite3_prepare16_v3()] assume that the prepared statement will
3535 ** be used just once or at most a few times and then destroyed using
3536 ** [sqlite3_finalize()] relatively soon. The current implementation acts
3537 ** on this hint by avoiding the use of [lookaside memory] so as not to
3538 ** deplete the limited store of lookaside memory. Future versions of
3539 ** SQLite may act on this hint differently.
3540 ** </dl>
3541 */
3542 enum SQLITE_PREPARE_PERSISTENT = 0x01;
3543 
3544 /*
3545 ** CAPI3REF: Compiling An SQL Statement
3546 ** KEYWORDS: {SQL statement compiler}
3547 ** METHOD: sqlite3
3548 ** CONSTRUCTOR: sqlite3_stmt
3549 **
3550 ** To execute an SQL statement, it must first be compiled into a byte-code
3551 ** program using one of these routines.  Or, in other words, these routines
3552 ** are constructors for the [prepared statement] object.
3553 **
3554 ** The preferred routine to use is [sqlite3_prepare_v2()].  The
3555 ** [sqlite3_prepare()] interface is legacy and should be avoided.
3556 ** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used
3557 ** for special purposes.
3558 **
3559 ** The use of the UTF-8 interfaces is preferred, as SQLite currently
3560 ** does all parsing using UTF-8.  The UTF-16 interfaces are provided
3561 ** as a convenience.  The UTF-16 interfaces work by converting the
3562 ** input text into UTF-8, then invoking the corresponding UTF-8 interface.
3563 **
3564 ** The first argument, "db", is a [database connection] obtained from a
3565 ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
3566 ** [sqlite3_open16()].  The database connection must not have been closed.
3567 **
3568 ** The second argument, "zSql", is the statement to be compiled, encoded
3569 ** as either UTF-8 or UTF-16.  The sqlite3_prepare(), sqlite3_prepare_v2(),
3570 ** and sqlite3_prepare_v3()
3571 ** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(),
3572 ** and sqlite3_prepare16_v3() use UTF-16.
3573 **
3574 ** ^If the nByte argument is negative, then zSql is read up to the
3575 ** first zero terminator. ^If nByte is positive, then it is the
3576 ** number of bytes read from zSql.  ^If nByte is zero, then no prepared
3577 ** statement is generated.
3578 ** If the caller knows that the supplied string is nul-terminated, then
3579 ** there is a small performance advantage to passing an nByte parameter that
3580 ** is the number of bytes in the input string <i>including</i>
3581 ** the nul-terminator.
3582 **
3583 ** ^If pzTail is not NULL then *pzTail is made to point to the first byte
3584 ** past the end of the first SQL statement in zSql.  These routines only
3585 ** compile the first statement in zSql, so *pzTail is left pointing to
3586 ** what remains uncompiled.
3587 **
3588 ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
3589 ** executed using [sqlite3_step()].  ^If there is an error, *ppStmt is set
3590 ** to NULL.  ^If the input text contains no SQL (if the input is an empty
3591 ** string or a comment) then *ppStmt is set to NULL.
3592 ** The calling procedure is responsible for deleting the compiled
3593 ** SQL statement using [sqlite3_finalize()] after it has finished with it.
3594 ** ppStmt may not be NULL.
3595 **
3596 ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
3597 ** otherwise an [error code] is returned.
3598 **
3599 ** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(),
3600 ** and sqlite3_prepare16_v3() interfaces are recommended for all new programs.
3601 ** The older interfaces (sqlite3_prepare() and sqlite3_prepare16())
3602 ** are retained for backwards compatibility, but their use is discouraged.
3603 ** ^In the "vX" interfaces, the prepared statement
3604 ** that is returned (the [sqlite3_stmt] object) contains a copy of the
3605 ** original SQL text. This causes the [sqlite3_step()] interface to
3606 ** behave differently in three ways:
3607 **
3608 ** <ol>
3609 ** <li>
3610 ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
3611 ** always used to do, [sqlite3_step()] will automatically recompile the SQL
3612 ** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
3613 ** retries will occur before sqlite3_step() gives up and returns an error.
3614 ** </li>
3615 **
3616 ** <li>
3617 ** ^When an error occurs, [sqlite3_step()] will return one of the detailed
3618 ** [error codes] or [extended error codes].  ^The legacy behavior was that
3619 ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
3620 ** and the application would have to make a second call to [sqlite3_reset()]
3621 ** in order to find the underlying cause of the problem. With the "v2" prepare
3622 ** interfaces, the underlying reason for the error is returned immediately.
3623 ** </li>
3624 **
3625 ** <li>
3626 ** ^If the specific value bound to [parameter | host parameter] in the
3627 ** WHERE clause might influence the choice of query plan for a statement,
3628 ** then the statement will be automatically recompiled, as if there had been
3629 ** a schema change, on the first  [sqlite3_step()] call following any change
3630 ** to the [sqlite3_bind_text | bindings] of that [parameter].
3631 ** ^The specific value of WHERE-clause [parameter] might influence the
3632 ** choice of query plan if the parameter is the left-hand side of a [LIKE]
3633 ** or [GLOB] operator or if the parameter is compared to an indexed column
3634 ** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.
3635 ** </li>
3636 **
3637 ** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having
3638 ** the extra prepFlags parameter, which is a bit array consisting of zero or
3639 ** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags.  ^The
3640 ** sqlite3_prepare_v2() interface works exactly the same as
3641 ** sqlite3_prepare_v3() with a zero prepFlags parameter.
3642 ** </ol>
3643 */
3644 /* Database handle */
3645 /* SQL statement, UTF-8 encoded */
3646 /* Maximum length of zSql in bytes. */
3647 /* OUT: Statement handle */
3648 /* OUT: Pointer to unused portion of zSql */
3649 int sqlite3_prepare(
3650     sqlite3* db,
3651     const(char)* zSql,
3652     int nByte,
3653     sqlite3_stmt** ppStmt,
3654     const(char*)* pzTail);
3655 
3656 /* Database handle */
3657 /* SQL statement, UTF-8 encoded */
3658 /* Maximum length of zSql in bytes. */
3659 /* OUT: Statement handle */
3660 /* OUT: Pointer to unused portion of zSql */
3661 int sqlite3_prepare_v2(
3662     sqlite3* db,
3663     const(char)* zSql,
3664     int nByte,
3665     sqlite3_stmt** ppStmt,
3666     const(char*)* pzTail);
3667 
3668 /* Database handle */
3669 /* SQL statement, UTF-8 encoded */
3670 /* Maximum length of zSql in bytes. */
3671 /* Zero or more SQLITE_PREPARE_ flags */
3672 /* OUT: Statement handle */
3673 /* OUT: Pointer to unused portion of zSql */
3674 int sqlite3_prepare_v3(
3675     sqlite3* db,
3676     const(char)* zSql,
3677     int nByte,
3678     uint prepFlags,
3679     sqlite3_stmt** ppStmt,
3680     const(char*)* pzTail);
3681 
3682 /* Database handle */
3683 /* SQL statement, UTF-16 encoded */
3684 /* Maximum length of zSql in bytes. */
3685 /* OUT: Statement handle */
3686 /* OUT: Pointer to unused portion of zSql */
3687 int sqlite3_prepare16(
3688     sqlite3* db,
3689     const(void)* zSql,
3690     int nByte,
3691     sqlite3_stmt** ppStmt,
3692     const(void*)* pzTail);
3693 
3694 /* Database handle */
3695 /* SQL statement, UTF-16 encoded */
3696 /* Maximum length of zSql in bytes. */
3697 /* OUT: Statement handle */
3698 /* OUT: Pointer to unused portion of zSql */
3699 int sqlite3_prepare16_v2(
3700     sqlite3* db,
3701     const(void)* zSql,
3702     int nByte,
3703     sqlite3_stmt** ppStmt,
3704     const(void*)* pzTail);
3705 
3706 /* Database handle */
3707 /* SQL statement, UTF-16 encoded */
3708 /* Maximum length of zSql in bytes. */
3709 /* Zero or more SQLITE_PREPARE_ flags */
3710 /* OUT: Statement handle */
3711 /* OUT: Pointer to unused portion of zSql */
3712 int sqlite3_prepare16_v3(
3713     sqlite3* db,
3714     const(void)* zSql,
3715     int nByte,
3716     uint prepFlags,
3717     sqlite3_stmt** ppStmt,
3718     const(void*)* pzTail);
3719 
3720 /*
3721 ** CAPI3REF: Retrieving Statement SQL
3722 ** METHOD: sqlite3_stmt
3723 **
3724 ** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8
3725 ** SQL text used to create [prepared statement] P if P was
3726 ** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()],
3727 ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
3728 ** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8
3729 ** string containing the SQL text of prepared statement P with
3730 ** [bound parameters] expanded.
3731 **
3732 ** ^(For example, if a prepared statement is created using the SQL
3733 ** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345
3734 ** and parameter :xyz is unbound, then sqlite3_sql() will return
3735 ** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql()
3736 ** will return "SELECT 2345,NULL".)^
3737 **
3738 ** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory
3739 ** is available to hold the result, or if the result would exceed the
3740 ** the maximum string length determined by the [SQLITE_LIMIT_LENGTH].
3741 **
3742 ** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of
3743 ** bound parameter expansions.  ^The [SQLITE_OMIT_TRACE] compile-time
3744 ** option causes sqlite3_expanded_sql() to always return NULL.
3745 **
3746 ** ^The string returned by sqlite3_sql(P) is managed by SQLite and is
3747 ** automatically freed when the prepared statement is finalized.
3748 ** ^The string returned by sqlite3_expanded_sql(P), on the other hand,
3749 ** is obtained from [sqlite3_malloc()] and must be free by the application
3750 ** by passing it to [sqlite3_free()].
3751 */
3752 const(char)* sqlite3_sql(sqlite3_stmt* pStmt);
3753 char* sqlite3_expanded_sql(sqlite3_stmt* pStmt);
3754 
3755 /*
3756 ** CAPI3REF: Determine If An SQL Statement Writes The Database
3757 ** METHOD: sqlite3_stmt
3758 **
3759 ** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
3760 ** and only if the [prepared statement] X makes no direct changes to
3761 ** the content of the database file.
3762 **
3763 ** Note that [application-defined SQL functions] or
3764 ** [virtual tables] might change the database indirectly as a side effect.
3765 ** ^(For example, if an application defines a function "eval()" that
3766 ** calls [sqlite3_exec()], then the following SQL statement would
3767 ** change the database file through side-effects:
3768 **
3769 ** <blockquote><pre>
3770 **    SELECT eval('DELETE FROM t1') FROM t2;
3771 ** </pre></blockquote>
3772 **
3773 ** But because the [SELECT] statement does not change the database file
3774 ** directly, sqlite3_stmt_readonly() would still return true.)^
3775 **
3776 ** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
3777 ** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
3778 ** since the statements themselves do not actually modify the database but
3779 ** rather they control the timing of when other statements modify the
3780 ** database.  ^The [ATTACH] and [DETACH] statements also cause
3781 ** sqlite3_stmt_readonly() to return true since, while those statements
3782 ** change the configuration of a database connection, they do not make
3783 ** changes to the content of the database files on disk.
3784 ** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since
3785 ** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and
3786 ** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so
3787 ** sqlite3_stmt_readonly() returns false for those commands.
3788 */
3789 int sqlite3_stmt_readonly(sqlite3_stmt* pStmt);
3790 
3791 /*
3792 ** CAPI3REF: Determine If A Prepared Statement Has Been Reset
3793 ** METHOD: sqlite3_stmt
3794 **
3795 ** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
3796 ** [prepared statement] S has been stepped at least once using
3797 ** [sqlite3_step(S)] but has neither run to completion (returned
3798 ** [SQLITE_DONE] from [sqlite3_step(S)]) nor
3799 ** been reset using [sqlite3_reset(S)].  ^The sqlite3_stmt_busy(S)
3800 ** interface returns false if S is a NULL pointer.  If S is not a
3801 ** NULL pointer and is not a pointer to a valid [prepared statement]
3802 ** object, then the behavior is undefined and probably undesirable.
3803 **
3804 ** This interface can be used in combination [sqlite3_next_stmt()]
3805 ** to locate all prepared statements associated with a database
3806 ** connection that are in need of being reset.  This can be used,
3807 ** for example, in diagnostic routines to search for prepared
3808 ** statements that are holding a transaction open.
3809 */
3810 int sqlite3_stmt_busy(sqlite3_stmt*);
3811 
3812 /*
3813 ** CAPI3REF: Dynamically Typed Value Object
3814 ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
3815 **
3816 ** SQLite uses the sqlite3_value object to represent all values
3817 ** that can be stored in a database table. SQLite uses dynamic typing
3818 ** for the values it stores.  ^Values stored in sqlite3_value objects
3819 ** can be integers, floating point values, strings, BLOBs, or NULL.
3820 **
3821 ** An sqlite3_value object may be either "protected" or "unprotected".
3822 ** Some interfaces require a protected sqlite3_value.  Other interfaces
3823 ** will accept either a protected or an unprotected sqlite3_value.
3824 ** Every interface that accepts sqlite3_value arguments specifies
3825 ** whether or not it requires a protected sqlite3_value.  The
3826 ** [sqlite3_value_dup()] interface can be used to construct a new
3827 ** protected sqlite3_value from an unprotected sqlite3_value.
3828 **
3829 ** The terms "protected" and "unprotected" refer to whether or not
3830 ** a mutex is held.  An internal mutex is held for a protected
3831 ** sqlite3_value object but no mutex is held for an unprotected
3832 ** sqlite3_value object.  If SQLite is compiled to be single-threaded
3833 ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
3834 ** or if SQLite is run in one of reduced mutex modes
3835 ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
3836 ** then there is no distinction between protected and unprotected
3837 ** sqlite3_value objects and they can be used interchangeably.  However,
3838 ** for maximum code portability it is recommended that applications
3839 ** still make the distinction between protected and unprotected
3840 ** sqlite3_value objects even when not strictly required.
3841 **
3842 ** ^The sqlite3_value objects that are passed as parameters into the
3843 ** implementation of [application-defined SQL functions] are protected.
3844 ** ^The sqlite3_value object returned by
3845 ** [sqlite3_column_value()] is unprotected.
3846 ** Unprotected sqlite3_value objects may only be used as arguments
3847 ** to [sqlite3_result_value()], [sqlite3_bind_value()], and
3848 ** [sqlite3_value_dup()].
3849 ** The [sqlite3_value_blob | sqlite3_value_type()] family of
3850 ** interfaces require protected sqlite3_value objects.
3851 */
3852 struct sqlite3_value;
3853 
3854 /*
3855 ** CAPI3REF: SQL Function Context Object
3856 **
3857 ** The context in which an SQL function executes is stored in an
3858 ** sqlite3_context object.  ^A pointer to an sqlite3_context object
3859 ** is always first parameter to [application-defined SQL functions].
3860 ** The application-defined SQL function implementation will pass this
3861 ** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
3862 ** [sqlite3_aggregate_context()], [sqlite3_user_data()],
3863 ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
3864 ** and/or [sqlite3_set_auxdata()].
3865 */
3866 struct sqlite3_context;
3867 
3868 /*
3869 ** CAPI3REF: Binding Values To Prepared Statements
3870 ** KEYWORDS: {host parameter} {host parameters} {host parameter name}
3871 ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
3872 ** METHOD: sqlite3_stmt
3873 **
3874 ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
3875 ** literals may be replaced by a [parameter] that matches one of following
3876 ** templates:
3877 **
3878 ** <ul>
3879 ** <li>  ?
3880 ** <li>  ?NNN
3881 ** <li>  :VVV
3882 ** <li>  @VVV
3883 ** <li>  $VVV
3884 ** </ul>
3885 **
3886 ** In the templates above, NNN represents an integer literal,
3887 ** and VVV represents an alphanumeric identifier.)^  ^The values of these
3888 ** parameters (also called "host parameter names" or "SQL parameters")
3889 ** can be set using the sqlite3_bind_*() routines defined here.
3890 **
3891 ** ^The first argument to the sqlite3_bind_*() routines is always
3892 ** a pointer to the [sqlite3_stmt] object returned from
3893 ** [sqlite3_prepare_v2()] or its variants.
3894 **
3895 ** ^The second argument is the index of the SQL parameter to be set.
3896 ** ^The leftmost SQL parameter has an index of 1.  ^When the same named
3897 ** SQL parameter is used more than once, second and subsequent
3898 ** occurrences have the same index as the first occurrence.
3899 ** ^The index for named parameters can be looked up using the
3900 ** [sqlite3_bind_parameter_index()] API if desired.  ^The index
3901 ** for "?NNN" parameters is the value of NNN.
3902 ** ^The NNN value must be between 1 and the [sqlite3_limit()]
3903 ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
3904 **
3905 ** ^The third argument is the value to bind to the parameter.
3906 ** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
3907 ** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
3908 ** is ignored and the end result is the same as sqlite3_bind_null().
3909 **
3910 ** ^(In those routines that have a fourth argument, its value is the
3911 ** number of bytes in the parameter.  To be clear: the value is the
3912 ** number of <u>bytes</u> in the value, not the number of characters.)^
3913 ** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
3914 ** is negative, then the length of the string is
3915 ** the number of bytes up to the first zero terminator.
3916 ** If the fourth parameter to sqlite3_bind_blob() is negative, then
3917 ** the behavior is undefined.
3918 ** If a non-negative fourth parameter is provided to sqlite3_bind_text()
3919 ** or sqlite3_bind_text16() or sqlite3_bind_text64() then
3920 ** that parameter must be the byte offset
3921 ** where the NUL terminator would occur assuming the string were NUL
3922 ** terminated.  If any NUL characters occur at byte offsets less than
3923 ** the value of the fourth parameter then the resulting string value will
3924 ** contain embedded NULs.  The result of expressions involving strings
3925 ** with embedded NULs is undefined.
3926 **
3927 ** ^The fifth argument to the BLOB and string binding interfaces
3928 ** is a destructor used to dispose of the BLOB or
3929 ** string after SQLite has finished with it.  ^The destructor is called
3930 ** to dispose of the BLOB or string even if the call to bind API fails.
3931 ** ^If the fifth argument is
3932 ** the special value [SQLITE_STATIC], then SQLite assumes that the
3933 ** information is in static, unmanaged space and does not need to be freed.
3934 ** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
3935 ** SQLite makes its own private copy of the data immediately, before
3936 ** the sqlite3_bind_*() routine returns.
3937 **
3938 ** ^The sixth argument to sqlite3_bind_text64() must be one of
3939 ** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]
3940 ** to specify the encoding of the text in the third parameter.  If
3941 ** the sixth argument to sqlite3_bind_text64() is not one of the
3942 ** allowed values shown above, or if the text encoding is different
3943 ** from the encoding specified by the sixth parameter, then the behavior
3944 ** is undefined.
3945 **
3946 ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
3947 ** is filled with zeroes.  ^A zeroblob uses a fixed amount of memory
3948 ** (just an integer to hold its size) while it is being processed.
3949 ** Zeroblobs are intended to serve as placeholders for BLOBs whose
3950 ** content is later written using
3951 ** [sqlite3_blob_open | incremental BLOB I/O] routines.
3952 ** ^A negative value for the zeroblob results in a zero-length BLOB.
3953 **
3954 ** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in
3955 ** [prepared statement] S to have an SQL value of NULL, but to also be
3956 ** associated with the pointer P of type T.  ^D is either a NULL pointer or
3957 ** a pointer to a destructor function for P. ^SQLite will invoke the
3958 ** destructor D with a single argument of P when it is finished using
3959 ** P.  The T parameter should be a static string, preferably a string
3960 ** literal. The sqlite3_bind_pointer() routine is part of the
3961 ** [pointer passing interface] added for SQLite 3.20.0.
3962 **
3963 ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
3964 ** for the [prepared statement] or with a prepared statement for which
3965 ** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
3966 ** then the call will return [SQLITE_MISUSE].  If any sqlite3_bind_()
3967 ** routine is passed a [prepared statement] that has been finalized, the
3968 ** result is undefined and probably harmful.
3969 **
3970 ** ^Bindings are not cleared by the [sqlite3_reset()] routine.
3971 ** ^Unbound parameters are interpreted as NULL.
3972 **
3973 ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
3974 ** [error code] if anything goes wrong.
3975 ** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB
3976 ** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or
3977 ** [SQLITE_MAX_LENGTH].
3978 ** ^[SQLITE_RANGE] is returned if the parameter
3979 ** index is out of range.  ^[SQLITE_NOMEM] is returned if malloc() fails.
3980 **
3981 ** See also: [sqlite3_bind_parameter_count()],
3982 ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
3983 */
3984 int sqlite3_bind_blob(sqlite3_stmt*, int, const(void)*, int n, void function(void*));
3985 int sqlite3_bind_blob64(
3986     sqlite3_stmt*,
3987     int,
3988     const(void)*,
3989     sqlite3_uint64,
3990     void function(void*));
3991 int sqlite3_bind_double(sqlite3_stmt*, int, double);
3992 int sqlite3_bind_int(sqlite3_stmt*, int, int);
3993 int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
3994 int sqlite3_bind_null(sqlite3_stmt*, int);
3995 int sqlite3_bind_text(sqlite3_stmt*, int, const(char)*, int, void function(void*));
3996 int sqlite3_bind_text16(sqlite3_stmt*, int, const(void)*, int, void function(void*));
3997 int sqlite3_bind_text64(
3998     sqlite3_stmt*,
3999     int,
4000     const(char)*,
4001     sqlite3_uint64,
4002     void function(void*),
4003     ubyte encoding);
4004 int sqlite3_bind_value(sqlite3_stmt*, int, const(sqlite3_value)*);
4005 int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const(char)*, void function(void*));
4006 int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
4007 int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64);
4008 
4009 /*
4010 ** CAPI3REF: Number Of SQL Parameters
4011 ** METHOD: sqlite3_stmt
4012 **
4013 ** ^This routine can be used to find the number of [SQL parameters]
4014 ** in a [prepared statement].  SQL parameters are tokens of the
4015 ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
4016 ** placeholders for values that are [sqlite3_bind_blob | bound]
4017 ** to the parameters at a later time.
4018 **
4019 ** ^(This routine actually returns the index of the largest (rightmost)
4020 ** parameter. For all forms except ?NNN, this will correspond to the
4021 ** number of unique parameters.  If parameters of the ?NNN form are used,
4022 ** there may be gaps in the list.)^
4023 **
4024 ** See also: [sqlite3_bind_blob|sqlite3_bind()],
4025 ** [sqlite3_bind_parameter_name()], and
4026 ** [sqlite3_bind_parameter_index()].
4027 */
4028 int sqlite3_bind_parameter_count(sqlite3_stmt*);
4029 
4030 /*
4031 ** CAPI3REF: Name Of A Host Parameter
4032 ** METHOD: sqlite3_stmt
4033 **
4034 ** ^The sqlite3_bind_parameter_name(P,N) interface returns
4035 ** the name of the N-th [SQL parameter] in the [prepared statement] P.
4036 ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
4037 ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
4038 ** respectively.
4039 ** In other words, the initial ":" or "$" or "@" or "?"
4040 ** is included as part of the name.)^
4041 ** ^Parameters of the form "?" without a following integer have no name
4042 ** and are referred to as "nameless" or "anonymous parameters".
4043 **
4044 ** ^The first host parameter has an index of 1, not 0.
4045 **
4046 ** ^If the value N is out of range or if the N-th parameter is
4047 ** nameless, then NULL is returned.  ^The returned string is
4048 ** always in UTF-8 encoding even if the named parameter was
4049 ** originally specified as UTF-16 in [sqlite3_prepare16()],
4050 ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
4051 **
4052 ** See also: [sqlite3_bind_blob|sqlite3_bind()],
4053 ** [sqlite3_bind_parameter_count()], and
4054 ** [sqlite3_bind_parameter_index()].
4055 */
4056 const(char)* sqlite3_bind_parameter_name(sqlite3_stmt*, int);
4057 
4058 /*
4059 ** CAPI3REF: Index Of A Parameter With A Given Name
4060 ** METHOD: sqlite3_stmt
4061 **
4062 ** ^Return the index of an SQL parameter given its name.  ^The
4063 ** index value returned is suitable for use as the second
4064 ** parameter to [sqlite3_bind_blob|sqlite3_bind()].  ^A zero
4065 ** is returned if no matching parameter is found.  ^The parameter
4066 ** name must be given in UTF-8 even if the original statement
4067 ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or
4068 ** [sqlite3_prepare16_v3()].
4069 **
4070 ** See also: [sqlite3_bind_blob|sqlite3_bind()],
4071 ** [sqlite3_bind_parameter_count()], and
4072 ** [sqlite3_bind_parameter_name()].
4073 */
4074 int sqlite3_bind_parameter_index(sqlite3_stmt*, const(char)* zName);
4075 
4076 /*
4077 ** CAPI3REF: Reset All Bindings On A Prepared Statement
4078 ** METHOD: sqlite3_stmt
4079 **
4080 ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
4081 ** the [sqlite3_bind_blob | bindings] on a [prepared statement].
4082 ** ^Use this routine to reset all host parameters to NULL.
4083 */
4084 int sqlite3_clear_bindings(sqlite3_stmt*);
4085 
4086 /*
4087 ** CAPI3REF: Number Of Columns In A Result Set
4088 ** METHOD: sqlite3_stmt
4089 **
4090 ** ^Return the number of columns in the result set returned by the
4091 ** [prepared statement]. ^If this routine returns 0, that means the
4092 ** [prepared statement] returns no data (for example an [UPDATE]).
4093 ** ^However, just because this routine returns a positive number does not
4094 ** mean that one or more rows of data will be returned.  ^A SELECT statement
4095 ** will always have a positive sqlite3_column_count() but depending on the
4096 ** WHERE clause constraints and the table content, it might return no rows.
4097 **
4098 ** See also: [sqlite3_data_count()]
4099 */
4100 int sqlite3_column_count(sqlite3_stmt* pStmt);
4101 
4102 /*
4103 ** CAPI3REF: Column Names In A Result Set
4104 ** METHOD: sqlite3_stmt
4105 **
4106 ** ^These routines return the name assigned to a particular column
4107 ** in the result set of a [SELECT] statement.  ^The sqlite3_column_name()
4108 ** interface returns a pointer to a zero-terminated UTF-8 string
4109 ** and sqlite3_column_name16() returns a pointer to a zero-terminated
4110 ** UTF-16 string.  ^The first parameter is the [prepared statement]
4111 ** that implements the [SELECT] statement. ^The second parameter is the
4112 ** column number.  ^The leftmost column is number 0.
4113 **
4114 ** ^The returned string pointer is valid until either the [prepared statement]
4115 ** is destroyed by [sqlite3_finalize()] or until the statement is automatically
4116 ** reprepared by the first call to [sqlite3_step()] for a particular run
4117 ** or until the next call to
4118 ** sqlite3_column_name() or sqlite3_column_name16() on the same column.
4119 **
4120 ** ^If sqlite3_malloc() fails during the processing of either routine
4121 ** (for example during a conversion from UTF-8 to UTF-16) then a
4122 ** NULL pointer is returned.
4123 **
4124 ** ^The name of a result column is the value of the "AS" clause for
4125 ** that column, if there is an AS clause.  If there is no AS clause
4126 ** then the name of the column is unspecified and may change from
4127 ** one release of SQLite to the next.
4128 */
4129 const(char)* sqlite3_column_name(sqlite3_stmt*, int N);
4130 const(void)* sqlite3_column_name16(sqlite3_stmt*, int N);
4131 
4132 /*
4133 ** CAPI3REF: Source Of Data In A Query Result
4134 ** METHOD: sqlite3_stmt
4135 **
4136 ** ^These routines provide a means to determine the database, table, and
4137 ** table column that is the origin of a particular result column in
4138 ** [SELECT] statement.
4139 ** ^The name of the database or table or column can be returned as
4140 ** either a UTF-8 or UTF-16 string.  ^The _database_ routines return
4141 ** the database name, the _table_ routines return the table name, and
4142 ** the origin_ routines return the column name.
4143 ** ^The returned string is valid until the [prepared statement] is destroyed
4144 ** using [sqlite3_finalize()] or until the statement is automatically
4145 ** reprepared by the first call to [sqlite3_step()] for a particular run
4146 ** or until the same information is requested
4147 ** again in a different encoding.
4148 **
4149 ** ^The names returned are the original un-aliased names of the
4150 ** database, table, and column.
4151 **
4152 ** ^The first argument to these interfaces is a [prepared statement].
4153 ** ^These functions return information about the Nth result column returned by
4154 ** the statement, where N is the second function argument.
4155 ** ^The left-most column is column 0 for these routines.
4156 **
4157 ** ^If the Nth column returned by the statement is an expression or
4158 ** subquery and is not a column value, then all of these functions return
4159 ** NULL.  ^These routine might also return NULL if a memory allocation error
4160 ** occurs.  ^Otherwise, they return the name of the attached database, table,
4161 ** or column that query result column was extracted from.
4162 **
4163 ** ^As with all other SQLite APIs, those whose names end with "16" return
4164 ** UTF-16 encoded strings and the other functions return UTF-8.
4165 **
4166 ** ^These APIs are only available if the library was compiled with the
4167 ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
4168 **
4169 ** If two or more threads call one or more of these routines against the same
4170 ** prepared statement and column at the same time then the results are
4171 ** undefined.
4172 **
4173 ** If two or more threads call one or more
4174 ** [sqlite3_column_database_name | column metadata interfaces]
4175 ** for the same [prepared statement] and result column
4176 ** at the same time then the results are undefined.
4177 */
4178 const(char)* sqlite3_column_database_name(sqlite3_stmt*, int);
4179 const(void)* sqlite3_column_database_name16(sqlite3_stmt*, int);
4180 const(char)* sqlite3_column_table_name(sqlite3_stmt*, int);
4181 const(void)* sqlite3_column_table_name16(sqlite3_stmt*, int);
4182 const(char)* sqlite3_column_origin_name(sqlite3_stmt*, int);
4183 const(void)* sqlite3_column_origin_name16(sqlite3_stmt*, int);
4184 
4185 /*
4186 ** CAPI3REF: Declared Datatype Of A Query Result
4187 ** METHOD: sqlite3_stmt
4188 **
4189 ** ^(The first parameter is a [prepared statement].
4190 ** If this statement is a [SELECT] statement and the Nth column of the
4191 ** returned result set of that [SELECT] is a table column (not an
4192 ** expression or subquery) then the declared type of the table
4193 ** column is returned.)^  ^If the Nth column of the result set is an
4194 ** expression or subquery, then a NULL pointer is returned.
4195 ** ^The returned string is always UTF-8 encoded.
4196 **
4197 ** ^(For example, given the database schema:
4198 **
4199 ** CREATE TABLE t1(c1 VARIANT);
4200 **
4201 ** and the following statement to be compiled:
4202 **
4203 ** SELECT c1 + 1, c1 FROM t1;
4204 **
4205 ** this routine would return the string "VARIANT" for the second result
4206 ** column (i==1), and a NULL pointer for the first result column (i==0).)^
4207 **
4208 ** ^SQLite uses dynamic run-time typing.  ^So just because a column
4209 ** is declared to contain a particular type does not mean that the
4210 ** data stored in that column is of the declared type.  SQLite is
4211 ** strongly typed, but the typing is dynamic not static.  ^Type
4212 ** is associated with individual values, not with the containers
4213 ** used to hold those values.
4214 */
4215 const(char)* sqlite3_column_decltype(sqlite3_stmt*, int);
4216 const(void)* sqlite3_column_decltype16(sqlite3_stmt*, int);
4217 
4218 /*
4219 ** CAPI3REF: Evaluate An SQL Statement
4220 ** METHOD: sqlite3_stmt
4221 **
4222 ** After a [prepared statement] has been prepared using any of
4223 ** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()],
4224 ** or [sqlite3_prepare16_v3()] or one of the legacy
4225 ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
4226 ** must be called one or more times to evaluate the statement.
4227 **
4228 ** The details of the behavior of the sqlite3_step() interface depend
4229 ** on whether the statement was prepared using the newer "vX" interfaces
4230 ** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()],
4231 ** [sqlite3_prepare16_v2()] or the older legacy
4232 ** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()].  The use of the
4233 ** new "vX" interface is recommended for new applications but the legacy
4234 ** interface will continue to be supported.
4235 **
4236 ** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
4237 ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
4238 ** ^With the "v2" interface, any of the other [result codes] or
4239 ** [extended result codes] might be returned as well.
4240 **
4241 ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
4242 ** database locks it needs to do its job.  ^If the statement is a [COMMIT]
4243 ** or occurs outside of an explicit transaction, then you can retry the
4244 ** statement.  If the statement is not a [COMMIT] and occurs within an
4245 ** explicit transaction then you should rollback the transaction before
4246 ** continuing.
4247 **
4248 ** ^[SQLITE_DONE] means that the statement has finished executing
4249 ** successfully.  sqlite3_step() should not be called again on this virtual
4250 ** machine without first calling [sqlite3_reset()] to reset the virtual
4251 ** machine back to its initial state.
4252 **
4253 ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
4254 ** is returned each time a new row of data is ready for processing by the
4255 ** caller. The values may be accessed using the [column access functions].
4256 ** sqlite3_step() is called again to retrieve the next row of data.
4257 **
4258 ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
4259 ** violation) has occurred.  sqlite3_step() should not be called again on
4260 ** the VM. More information may be found by calling [sqlite3_errmsg()].
4261 ** ^With the legacy interface, a more specific error code (for example,
4262 ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
4263 ** can be obtained by calling [sqlite3_reset()] on the
4264 ** [prepared statement].  ^In the "v2" interface,
4265 ** the more specific error code is returned directly by sqlite3_step().
4266 **
4267 ** [SQLITE_MISUSE] means that the this routine was called inappropriately.
4268 ** Perhaps it was called on a [prepared statement] that has
4269 ** already been [sqlite3_finalize | finalized] or on one that had
4270 ** previously returned [SQLITE_ERROR] or [SQLITE_DONE].  Or it could
4271 ** be the case that the same database connection is being used by two or
4272 ** more threads at the same moment in time.
4273 **
4274 ** For all versions of SQLite up to and including 3.6.23.1, a call to
4275 ** [sqlite3_reset()] was required after sqlite3_step() returned anything
4276 ** other than [SQLITE_ROW] before any subsequent invocation of
4277 ** sqlite3_step().  Failure to reset the prepared statement using
4278 ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
4279 ** sqlite3_step().  But after [version 3.6.23.1] ([dateof:3.6.23.1],
4280 ** sqlite3_step() began
4281 ** calling [sqlite3_reset()] automatically in this circumstance rather
4282 ** than returning [SQLITE_MISUSE].  This is not considered a compatibility
4283 ** break because any application that ever receives an SQLITE_MISUSE error
4284 ** is broken by definition.  The [SQLITE_OMIT_AUTORESET] compile-time option
4285 ** can be used to restore the legacy behavior.
4286 **
4287 ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
4288 ** API always returns a generic error code, [SQLITE_ERROR], following any
4289 ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE].  You must call
4290 ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
4291 ** specific [error codes] that better describes the error.
4292 ** We admit that this is a goofy design.  The problem has been fixed
4293 ** with the "v2" interface.  If you prepare all of your SQL statements
4294 ** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()]
4295 ** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead
4296 ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
4297 ** then the more specific [error codes] are returned directly
4298 ** by sqlite3_step().  The use of the "vX" interfaces is recommended.
4299 */
4300 int sqlite3_step(sqlite3_stmt*);
4301 
4302 /*
4303 ** CAPI3REF: Number of columns in a result set
4304 ** METHOD: sqlite3_stmt
4305 **
4306 ** ^The sqlite3_data_count(P) interface returns the number of columns in the
4307 ** current row of the result set of [prepared statement] P.
4308 ** ^If prepared statement P does not have results ready to return
4309 ** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
4310 ** interfaces) then sqlite3_data_count(P) returns 0.
4311 ** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
4312 ** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
4313 ** [sqlite3_step](P) returned [SQLITE_DONE].  ^The sqlite3_data_count(P)
4314 ** will return non-zero if previous call to [sqlite3_step](P) returned
4315 ** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
4316 ** where it always returns zero since each step of that multi-step
4317 ** pragma returns 0 columns of data.
4318 **
4319 ** See also: [sqlite3_column_count()]
4320 */
4321 int sqlite3_data_count(sqlite3_stmt* pStmt);
4322 
4323 /*
4324 ** CAPI3REF: Fundamental Datatypes
4325 ** KEYWORDS: SQLITE_TEXT
4326 **
4327 ** ^(Every value in SQLite has one of five fundamental datatypes:
4328 **
4329 ** <ul>
4330 ** <li> 64-bit signed integer
4331 ** <li> 64-bit IEEE floating point number
4332 ** <li> string
4333 ** <li> BLOB
4334 ** <li> NULL
4335 ** </ul>)^
4336 **
4337 ** These constants are codes for each of those types.
4338 **
4339 ** Note that the SQLITE_TEXT constant was also used in SQLite version 2
4340 ** for a completely different meaning.  Software that links against both
4341 ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
4342 ** SQLITE_TEXT.
4343 */
4344 enum SQLITE_INTEGER = 1;
4345 enum SQLITE_FLOAT = 2;
4346 enum SQLITE_BLOB = 4;
4347 enum SQLITE_NULL = 5;
4348 
4349 enum SQLITE_TEXT = 3;
4350 
4351 enum SQLITE3_TEXT = 3;
4352 
4353 /*
4354 ** CAPI3REF: Result Values From A Query
4355 ** KEYWORDS: {column access functions}
4356 ** METHOD: sqlite3_stmt
4357 **
4358 ** <b>Summary:</b>
4359 ** <blockquote><table border=0 cellpadding=0 cellspacing=0>
4360 ** <tr><td><b>sqlite3_column_blob</b><td>&rarr;<td>BLOB result
4361 ** <tr><td><b>sqlite3_column_double</b><td>&rarr;<td>REAL result
4362 ** <tr><td><b>sqlite3_column_int</b><td>&rarr;<td>32-bit INTEGER result
4363 ** <tr><td><b>sqlite3_column_int64</b><td>&rarr;<td>64-bit INTEGER result
4364 ** <tr><td><b>sqlite3_column_text</b><td>&rarr;<td>UTF-8 TEXT result
4365 ** <tr><td><b>sqlite3_column_text16</b><td>&rarr;<td>UTF-16 TEXT result
4366 ** <tr><td><b>sqlite3_column_value</b><td>&rarr;<td>The result as an
4367 ** [sqlite3_value|unprotected sqlite3_value] object.
4368 ** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
4369 ** <tr><td><b>sqlite3_column_bytes</b><td>&rarr;<td>Size of a BLOB
4370 ** or a UTF-8 TEXT result in bytes
4371 ** <tr><td><b>sqlite3_column_bytes16&nbsp;&nbsp;</b>
4372 ** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
4373 ** TEXT in bytes
4374 ** <tr><td><b>sqlite3_column_type</b><td>&rarr;<td>Default
4375 ** datatype of the result
4376 ** </table></blockquote>
4377 **
4378 ** <b>Details:</b>
4379 **
4380 ** ^These routines return information about a single column of the current
4381 ** result row of a query.  ^In every case the first argument is a pointer
4382 ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
4383 ** that was returned from [sqlite3_prepare_v2()] or one of its variants)
4384 ** and the second argument is the index of the column for which information
4385 ** should be returned. ^The leftmost column of the result set has the index 0.
4386 ** ^The number of columns in the result can be determined using
4387 ** [sqlite3_column_count()].
4388 **
4389 ** If the SQL statement does not currently point to a valid row, or if the
4390 ** column index is out of range, the result is undefined.
4391 ** These routines may only be called when the most recent call to
4392 ** [sqlite3_step()] has returned [SQLITE_ROW] and neither
4393 ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
4394 ** If any of these routines are called after [sqlite3_reset()] or
4395 ** [sqlite3_finalize()] or after [sqlite3_step()] has returned
4396 ** something other than [SQLITE_ROW], the results are undefined.
4397 ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
4398 ** are called from a different thread while any of these routines
4399 ** are pending, then the results are undefined.
4400 **
4401 ** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16)
4402 ** each return the value of a result column in a specific data format.  If
4403 ** the result column is not initially in the requested format (for example,
4404 ** if the query returns an integer but the sqlite3_column_text() interface
4405 ** is used to extract the value) then an automatic type conversion is performed.
4406 **
4407 ** ^The sqlite3_column_type() routine returns the
4408 ** [SQLITE_INTEGER | datatype code] for the initial data type
4409 ** of the result column.  ^The returned value is one of [SQLITE_INTEGER],
4410 ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].
4411 ** The return value of sqlite3_column_type() can be used to decide which
4412 ** of the first six interface should be used to extract the column value.
4413 ** The value returned by sqlite3_column_type() is only meaningful if no
4414 ** automatic type conversions have occurred for the value in question.
4415 ** After a type conversion, the result of calling sqlite3_column_type()
4416 ** is undefined, though harmless.  Future
4417 ** versions of SQLite may change the behavior of sqlite3_column_type()
4418 ** following a type conversion.
4419 **
4420 ** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes()
4421 ** or sqlite3_column_bytes16() interfaces can be used to determine the size
4422 ** of that BLOB or string.
4423 **
4424 ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
4425 ** routine returns the number of bytes in that BLOB or string.
4426 ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
4427 ** the string to UTF-8 and then returns the number of bytes.
4428 ** ^If the result is a numeric value then sqlite3_column_bytes() uses
4429 ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
4430 ** the number of bytes in that string.
4431 ** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
4432 **
4433 ** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
4434 ** routine returns the number of bytes in that BLOB or string.
4435 ** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
4436 ** the string to UTF-16 and then returns the number of bytes.
4437 ** ^If the result is a numeric value then sqlite3_column_bytes16() uses
4438 ** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
4439 ** the number of bytes in that string.
4440 ** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
4441 **
4442 ** ^The values returned by [sqlite3_column_bytes()] and
4443 ** [sqlite3_column_bytes16()] do not include the zero terminators at the end
4444 ** of the string.  ^For clarity: the values returned by
4445 ** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
4446 ** bytes in the string, not the number of characters.
4447 **
4448 ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
4449 ** even empty strings, are always zero-terminated.  ^The return
4450 ** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
4451 **
4452 ** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an
4453 ** [unprotected sqlite3_value] object.  In a multithreaded environment,
4454 ** an unprotected sqlite3_value object may only be used safely with
4455 ** [sqlite3_bind_value()] and [sqlite3_result_value()].
4456 ** If the [unprotected sqlite3_value] object returned by
4457 ** [sqlite3_column_value()] is used in any other way, including calls
4458 ** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
4459 ** or [sqlite3_value_bytes()], the behavior is not threadsafe.
4460 ** Hence, the sqlite3_column_value() interface
4461 ** is normally only useful within the implementation of
4462 ** [application-defined SQL functions] or [virtual tables], not within
4463 ** top-level application code.
4464 **
4465 ** The these routines may attempt to convert the datatype of the result.
4466 ** ^For example, if the internal representation is FLOAT and a text result
4467 ** is requested, [sqlite3_snprintf()] is used internally to perform the
4468 ** conversion automatically.  ^(The following table details the conversions
4469 ** that are applied:
4470 **
4471 ** <blockquote>
4472 ** <table border="1">
4473 ** <tr><th> Internal<br>Type <th> Requested<br>Type <th>  Conversion
4474 **
4475 ** <tr><td>  NULL    <td> INTEGER   <td> Result is 0
4476 ** <tr><td>  NULL    <td>  FLOAT    <td> Result is 0.0
4477 ** <tr><td>  NULL    <td>   TEXT    <td> Result is a NULL pointer
4478 ** <tr><td>  NULL    <td>   BLOB    <td> Result is a NULL pointer
4479 ** <tr><td> INTEGER  <td>  FLOAT    <td> Convert from integer to float
4480 ** <tr><td> INTEGER  <td>   TEXT    <td> ASCII rendering of the integer
4481 ** <tr><td> INTEGER  <td>   BLOB    <td> Same as INTEGER->TEXT
4482 ** <tr><td>  FLOAT   <td> INTEGER   <td> [CAST] to INTEGER
4483 ** <tr><td>  FLOAT   <td>   TEXT    <td> ASCII rendering of the float
4484 ** <tr><td>  FLOAT   <td>   BLOB    <td> [CAST] to BLOB
4485 ** <tr><td>  TEXT    <td> INTEGER   <td> [CAST] to INTEGER
4486 ** <tr><td>  TEXT    <td>  FLOAT    <td> [CAST] to REAL
4487 ** <tr><td>  TEXT    <td>   BLOB    <td> No change
4488 ** <tr><td>  BLOB    <td> INTEGER   <td> [CAST] to INTEGER
4489 ** <tr><td>  BLOB    <td>  FLOAT    <td> [CAST] to REAL
4490 ** <tr><td>  BLOB    <td>   TEXT    <td> Add a zero terminator if needed
4491 ** </table>
4492 ** </blockquote>)^
4493 **
4494 ** Note that when type conversions occur, pointers returned by prior
4495 ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
4496 ** sqlite3_column_text16() may be invalidated.
4497 ** Type conversions and pointer invalidations might occur
4498 ** in the following cases:
4499 **
4500 ** <ul>
4501 ** <li> The initial content is a BLOB and sqlite3_column_text() or
4502 **      sqlite3_column_text16() is called.  A zero-terminator might
4503 **      need to be added to the string.</li>
4504 ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
4505 **      sqlite3_column_text16() is called.  The content must be converted
4506 **      to UTF-16.</li>
4507 ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
4508 **      sqlite3_column_text() is called.  The content must be converted
4509 **      to UTF-8.</li>
4510 ** </ul>
4511 **
4512 ** ^Conversions between UTF-16be and UTF-16le are always done in place and do
4513 ** not invalidate a prior pointer, though of course the content of the buffer
4514 ** that the prior pointer references will have been modified.  Other kinds
4515 ** of conversion are done in place when it is possible, but sometimes they
4516 ** are not possible and in those cases prior pointers are invalidated.
4517 **
4518 ** The safest policy is to invoke these routines
4519 ** in one of the following ways:
4520 **
4521 ** <ul>
4522 **  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
4523 **  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
4524 **  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
4525 ** </ul>
4526 **
4527 ** In other words, you should call sqlite3_column_text(),
4528 ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
4529 ** into the desired format, then invoke sqlite3_column_bytes() or
4530 ** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
4531 ** to sqlite3_column_text() or sqlite3_column_blob() with calls to
4532 ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
4533 ** with calls to sqlite3_column_bytes().
4534 **
4535 ** ^The pointers returned are valid until a type conversion occurs as
4536 ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
4537 ** [sqlite3_finalize()] is called.  ^The memory space used to hold strings
4538 ** and BLOBs is freed automatically.  Do not pass the pointers returned
4539 ** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
4540 ** [sqlite3_free()].
4541 **
4542 ** ^(If a memory allocation error occurs during the evaluation of any
4543 ** of these routines, a default value is returned.  The default value
4544 ** is either the integer 0, the floating point number 0.0, or a NULL
4545 ** pointer.  Subsequent calls to [sqlite3_errcode()] will return
4546 ** [SQLITE_NOMEM].)^
4547 */
4548 const(void)* sqlite3_column_blob(sqlite3_stmt*, int iCol);
4549 double sqlite3_column_double(sqlite3_stmt*, int iCol);
4550 int sqlite3_column_int(sqlite3_stmt*, int iCol);
4551 sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
4552 const(ubyte)* sqlite3_column_text(sqlite3_stmt*, int iCol);
4553 const(void)* sqlite3_column_text16(sqlite3_stmt*, int iCol);
4554 sqlite3_value* sqlite3_column_value(sqlite3_stmt*, int iCol);
4555 int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
4556 int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
4557 int sqlite3_column_type(sqlite3_stmt*, int iCol);
4558 
4559 /*
4560 ** CAPI3REF: Destroy A Prepared Statement Object
4561 ** DESTRUCTOR: sqlite3_stmt
4562 **
4563 ** ^The sqlite3_finalize() function is called to delete a [prepared statement].
4564 ** ^If the most recent evaluation of the statement encountered no errors
4565 ** or if the statement is never been evaluated, then sqlite3_finalize() returns
4566 ** SQLITE_OK.  ^If the most recent evaluation of statement S failed, then
4567 ** sqlite3_finalize(S) returns the appropriate [error code] or
4568 ** [extended error code].
4569 **
4570 ** ^The sqlite3_finalize(S) routine can be called at any point during
4571 ** the life cycle of [prepared statement] S:
4572 ** before statement S is ever evaluated, after
4573 ** one or more calls to [sqlite3_reset()], or after any call
4574 ** to [sqlite3_step()] regardless of whether or not the statement has
4575 ** completed execution.
4576 **
4577 ** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
4578 **
4579 ** The application must finalize every [prepared statement] in order to avoid
4580 ** resource leaks.  It is a grievous error for the application to try to use
4581 ** a prepared statement after it has been finalized.  Any use of a prepared
4582 ** statement after it has been finalized can result in undefined and
4583 ** undesirable behavior such as segfaults and heap corruption.
4584 */
4585 int sqlite3_finalize(sqlite3_stmt* pStmt);
4586 
4587 /*
4588 ** CAPI3REF: Reset A Prepared Statement Object
4589 ** METHOD: sqlite3_stmt
4590 **
4591 ** The sqlite3_reset() function is called to reset a [prepared statement]
4592 ** object back to its initial state, ready to be re-executed.
4593 ** ^Any SQL statement variables that had values bound to them using
4594 ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
4595 ** Use [sqlite3_clear_bindings()] to reset the bindings.
4596 **
4597 ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
4598 ** back to the beginning of its program.
4599 **
4600 ** ^If the most recent call to [sqlite3_step(S)] for the
4601 ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
4602 ** or if [sqlite3_step(S)] has never before been called on S,
4603 ** then [sqlite3_reset(S)] returns [SQLITE_OK].
4604 **
4605 ** ^If the most recent call to [sqlite3_step(S)] for the
4606 ** [prepared statement] S indicated an error, then
4607 ** [sqlite3_reset(S)] returns an appropriate [error code].
4608 **
4609 ** ^The [sqlite3_reset(S)] interface does not change the values
4610 ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
4611 */
4612 int sqlite3_reset(sqlite3_stmt* pStmt);
4613 
4614 /*
4615 ** CAPI3REF: Create Or Redefine SQL Functions
4616 ** KEYWORDS: {function creation routines}
4617 ** KEYWORDS: {application-defined SQL function}
4618 ** KEYWORDS: {application-defined SQL functions}
4619 ** METHOD: sqlite3
4620 **
4621 ** ^These functions (collectively known as "function creation routines")
4622 ** are used to add SQL functions or aggregates or to redefine the behavior
4623 ** of existing SQL functions or aggregates.  The only differences between
4624 ** these routines are the text encoding expected for
4625 ** the second parameter (the name of the function being created)
4626 ** and the presence or absence of a destructor callback for
4627 ** the application data pointer.
4628 **
4629 ** ^The first parameter is the [database connection] to which the SQL
4630 ** function is to be added.  ^If an application uses more than one database
4631 ** connection then application-defined SQL functions must be added
4632 ** to each database connection separately.
4633 **
4634 ** ^The second parameter is the name of the SQL function to be created or
4635 ** redefined.  ^The length of the name is limited to 255 bytes in a UTF-8
4636 ** representation, exclusive of the zero-terminator.  ^Note that the name
4637 ** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
4638 ** ^Any attempt to create a function with a longer name
4639 ** will result in [SQLITE_MISUSE] being returned.
4640 **
4641 ** ^The third parameter (nArg)
4642 ** is the number of arguments that the SQL function or
4643 ** aggregate takes. ^If this parameter is -1, then the SQL function or
4644 ** aggregate may take any number of arguments between 0 and the limit
4645 ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]).  If the third
4646 ** parameter is less than -1 or greater than 127 then the behavior is
4647 ** undefined.
4648 **
4649 ** ^The fourth parameter, eTextRep, specifies what
4650 ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
4651 ** its parameters.  The application should set this parameter to
4652 ** [SQLITE_UTF16LE] if the function implementation invokes
4653 ** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
4654 ** implementation invokes [sqlite3_value_text16be()] on an input, or
4655 ** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
4656 ** otherwise.  ^The same SQL function may be registered multiple times using
4657 ** different preferred text encodings, with different implementations for
4658 ** each encoding.
4659 ** ^When multiple implementations of the same function are available, SQLite
4660 ** will pick the one that involves the least amount of data conversion.
4661 **
4662 ** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
4663 ** to signal that the function will always return the same result given
4664 ** the same inputs within a single SQL statement.  Most SQL functions are
4665 ** deterministic.  The built-in [random()] SQL function is an example of a
4666 ** function that is not deterministic.  The SQLite query planner is able to
4667 ** perform additional optimizations on deterministic functions, so use
4668 ** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
4669 **
4670 ** ^(The fifth parameter is an arbitrary pointer.  The implementation of the
4671 ** function can gain access to this pointer using [sqlite3_user_data()].)^
4672 **
4673 ** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are
4674 ** pointers to C-language functions that implement the SQL function or
4675 ** aggregate. ^A scalar SQL function requires an implementation of the xFunc
4676 ** callback only; NULL pointers must be passed as the xStep and xFinal
4677 ** parameters. ^An aggregate SQL function requires an implementation of xStep
4678 ** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
4679 ** SQL function or aggregate, pass NULL pointers for all three function
4680 ** callbacks.
4681 **
4682 ** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL,
4683 ** then it is destructor for the application data pointer.
4684 ** The destructor is invoked when the function is deleted, either by being
4685 ** overloaded or when the database connection closes.)^
4686 ** ^The destructor is also invoked if the call to
4687 ** sqlite3_create_function_v2() fails.
4688 ** ^When the destructor callback of the tenth parameter is invoked, it
4689 ** is passed a single argument which is a copy of the application data
4690 ** pointer which was the fifth parameter to sqlite3_create_function_v2().
4691 **
4692 ** ^It is permitted to register multiple implementations of the same
4693 ** functions with the same name but with either differing numbers of
4694 ** arguments or differing preferred text encodings.  ^SQLite will use
4695 ** the implementation that most closely matches the way in which the
4696 ** SQL function is used.  ^A function implementation with a non-negative
4697 ** nArg parameter is a better match than a function implementation with
4698 ** a negative nArg.  ^A function where the preferred text encoding
4699 ** matches the database encoding is a better
4700 ** match than a function where the encoding is different.
4701 ** ^A function where the encoding difference is between UTF16le and UTF16be
4702 ** is a closer match than a function where the encoding difference is
4703 ** between UTF8 and UTF16.
4704 **
4705 ** ^Built-in functions may be overloaded by new application-defined functions.
4706 **
4707 ** ^An application-defined function is permitted to call other
4708 ** SQLite interfaces.  However, such calls must not
4709 ** close the database connection nor finalize or reset the prepared
4710 ** statement in which the function is running.
4711 */
4712 int sqlite3_create_function(
4713     sqlite3* db,
4714     const(char)* zFunctionName,
4715     int nArg,
4716     int eTextRep,
4717     void* pApp,
4718     void function(sqlite3_context*, int, sqlite3_value**) xFunc,
4719     void function(sqlite3_context*, int, sqlite3_value**) xStep,
4720     void function(sqlite3_context*) xFinal);
4721 int sqlite3_create_function16(
4722     sqlite3* db,
4723     const(void)* zFunctionName,
4724     int nArg,
4725     int eTextRep,
4726     void* pApp,
4727     void function(sqlite3_context*, int, sqlite3_value**) xFunc,
4728     void function(sqlite3_context*, int, sqlite3_value**) xStep,
4729     void function(sqlite3_context*) xFinal);
4730 int sqlite3_create_function_v2(
4731     sqlite3* db,
4732     const(char)* zFunctionName,
4733     int nArg,
4734     int eTextRep,
4735     void* pApp,
4736     void function(sqlite3_context*, int, sqlite3_value**) xFunc,
4737     void function(sqlite3_context*, int, sqlite3_value**) xStep,
4738     void function(sqlite3_context*) xFinal,
4739     void function(void*) xDestroy);
4740 
4741 /*
4742 ** CAPI3REF: Text Encodings
4743 **
4744 ** These constant define integer codes that represent the various
4745 ** text encodings supported by SQLite.
4746 */
4747 enum SQLITE_UTF8 = 1; /* IMP: R-37514-35566 */
4748 enum SQLITE_UTF16LE = 2; /* IMP: R-03371-37637 */
4749 enum SQLITE_UTF16BE = 3; /* IMP: R-51971-34154 */
4750 enum SQLITE_UTF16 = 4; /* Use native byte order */
4751 enum SQLITE_ANY = 5; /* Deprecated */
4752 enum SQLITE_UTF16_ALIGNED = 8; /* sqlite3_create_collation only */
4753 
4754 /*
4755 ** CAPI3REF: Function Flags
4756 **
4757 ** These constants may be ORed together with the
4758 ** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
4759 ** to [sqlite3_create_function()], [sqlite3_create_function16()], or
4760 ** [sqlite3_create_function_v2()].
4761 */
4762 enum SQLITE_DETERMINISTIC = 0x800;
4763 
4764 /*
4765 ** CAPI3REF: Deprecated Functions
4766 ** DEPRECATED
4767 **
4768 ** These functions are [deprecated].  In order to maintain
4769 ** backwards compatibility with older code, these functions continue
4770 ** to be supported.  However, new applications should avoid
4771 ** the use of these functions.  To encourage programmers to avoid
4772 ** these functions, we will not explain what they do.
4773 */
4774 
4775 int sqlite3_aggregate_count(sqlite3_context*);
4776 int sqlite3_expired(sqlite3_stmt*);
4777 int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
4778 int sqlite3_global_recover();
4779 void sqlite3_thread_cleanup();
4780 int sqlite3_memory_alarm(
4781     void function(void*, sqlite3_int64, int),
4782     void*,
4783     sqlite3_int64);
4784 
4785 /*
4786 ** CAPI3REF: Obtaining SQL Values
4787 ** METHOD: sqlite3_value
4788 **
4789 ** <b>Summary:</b>
4790 ** <blockquote><table border=0 cellpadding=0 cellspacing=0>
4791 ** <tr><td><b>sqlite3_value_blob</b><td>&rarr;<td>BLOB value
4792 ** <tr><td><b>sqlite3_value_double</b><td>&rarr;<td>REAL value
4793 ** <tr><td><b>sqlite3_value_int</b><td>&rarr;<td>32-bit INTEGER value
4794 ** <tr><td><b>sqlite3_value_int64</b><td>&rarr;<td>64-bit INTEGER value
4795 ** <tr><td><b>sqlite3_value_pointer</b><td>&rarr;<td>Pointer value
4796 ** <tr><td><b>sqlite3_value_text</b><td>&rarr;<td>UTF-8 TEXT value
4797 ** <tr><td><b>sqlite3_value_text16</b><td>&rarr;<td>UTF-16 TEXT value in
4798 ** the native byteorder
4799 ** <tr><td><b>sqlite3_value_text16be</b><td>&rarr;<td>UTF-16be TEXT value
4800 ** <tr><td><b>sqlite3_value_text16le</b><td>&rarr;<td>UTF-16le TEXT value
4801 ** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
4802 ** <tr><td><b>sqlite3_value_bytes</b><td>&rarr;<td>Size of a BLOB
4803 ** or a UTF-8 TEXT in bytes
4804 ** <tr><td><b>sqlite3_value_bytes16&nbsp;&nbsp;</b>
4805 ** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
4806 ** TEXT in bytes
4807 ** <tr><td><b>sqlite3_value_type</b><td>&rarr;<td>Default
4808 ** datatype of the value
4809 ** <tr><td><b>sqlite3_value_numeric_type&nbsp;&nbsp;</b>
4810 ** <td>&rarr;&nbsp;&nbsp;<td>Best numeric datatype of the value
4811 ** </table></blockquote>
4812 **
4813 ** <b>Details:</b>
4814 **
4815 ** These routines extract type, size, and content information from
4816 ** [protected sqlite3_value] objects.  Protected sqlite3_value objects
4817 ** are used to pass parameter information into implementation of
4818 ** [application-defined SQL functions] and [virtual tables].
4819 **
4820 ** These routines work only with [protected sqlite3_value] objects.
4821 ** Any attempt to use these routines on an [unprotected sqlite3_value]
4822 ** is not threadsafe.
4823 **
4824 ** ^These routines work just like the corresponding [column access functions]
4825 ** except that these routines take a single [protected sqlite3_value] object
4826 ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
4827 **
4828 ** ^The sqlite3_value_text16() interface extracts a UTF-16 string
4829 ** in the native byte-order of the host machine.  ^The
4830 ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
4831 ** extract UTF-16 strings as big-endian and little-endian respectively.
4832 **
4833 ** ^If [sqlite3_value] object V was initialized
4834 ** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)]
4835 ** and if X and Y are strings that compare equal according to strcmp(X,Y),
4836 ** then sqlite3_value_pointer(V,Y) will return the pointer P.  ^Otherwise,
4837 ** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer()
4838 ** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
4839 **
4840 ** ^(The sqlite3_value_type(V) interface returns the
4841 ** [SQLITE_INTEGER | datatype code] for the initial datatype of the
4842 ** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER],
4843 ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^
4844 ** Other interfaces might change the datatype for an sqlite3_value object.
4845 ** For example, if the datatype is initially SQLITE_INTEGER and
4846 ** sqlite3_value_text(V) is called to extract a text value for that
4847 ** integer, then subsequent calls to sqlite3_value_type(V) might return
4848 ** SQLITE_TEXT.  Whether or not a persistent internal datatype conversion
4849 ** occurs is undefined and may change from one release of SQLite to the next.
4850 **
4851 ** ^(The sqlite3_value_numeric_type() interface attempts to apply
4852 ** numeric affinity to the value.  This means that an attempt is
4853 ** made to convert the value to an integer or floating point.  If
4854 ** such a conversion is possible without loss of information (in other
4855 ** words, if the value is a string that looks like a number)
4856 ** then the conversion is performed.  Otherwise no conversion occurs.
4857 ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
4858 **
4859 ** Please pay particular attention to the fact that the pointer returned
4860 ** from [sqlite3_value_blob()], [sqlite3_value_text()], or
4861 ** [sqlite3_value_text16()] can be invalidated by a subsequent call to
4862 ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
4863 ** or [sqlite3_value_text16()].
4864 **
4865 ** These routines must be called from the same thread as
4866 ** the SQL function that supplied the [sqlite3_value*] parameters.
4867 */
4868 const(void)* sqlite3_value_blob(sqlite3_value*);
4869 double sqlite3_value_double(sqlite3_value*);
4870 int sqlite3_value_int(sqlite3_value*);
4871 sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
4872 void* sqlite3_value_pointer(sqlite3_value*, const(char)*);
4873 const(ubyte)* sqlite3_value_text(sqlite3_value*);
4874 const(void)* sqlite3_value_text16(sqlite3_value*);
4875 const(void)* sqlite3_value_text16le(sqlite3_value*);
4876 const(void)* sqlite3_value_text16be(sqlite3_value*);
4877 int sqlite3_value_bytes(sqlite3_value*);
4878 int sqlite3_value_bytes16(sqlite3_value*);
4879 int sqlite3_value_type(sqlite3_value*);
4880 int sqlite3_value_numeric_type(sqlite3_value*);
4881 
4882 /*
4883 ** CAPI3REF: Finding The Subtype Of SQL Values
4884 ** METHOD: sqlite3_value
4885 **
4886 ** The sqlite3_value_subtype(V) function returns the subtype for
4887 ** an [application-defined SQL function] argument V.  The subtype
4888 ** information can be used to pass a limited amount of context from
4889 ** one SQL function to another.  Use the [sqlite3_result_subtype()]
4890 ** routine to set the subtype for the return value of an SQL function.
4891 */
4892 uint sqlite3_value_subtype(sqlite3_value*);
4893 
4894 /*
4895 ** CAPI3REF: Copy And Free SQL Values
4896 ** METHOD: sqlite3_value
4897 **
4898 ** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value]
4899 ** object D and returns a pointer to that copy.  ^The [sqlite3_value] returned
4900 ** is a [protected sqlite3_value] object even if the input is not.
4901 ** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a
4902 ** memory allocation fails.
4903 **
4904 ** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object
4905 ** previously obtained from [sqlite3_value_dup()].  ^If V is a NULL pointer
4906 ** then sqlite3_value_free(V) is a harmless no-op.
4907 */
4908 sqlite3_value* sqlite3_value_dup(const(sqlite3_value)*);
4909 void sqlite3_value_free(sqlite3_value*);
4910 
4911 /*
4912 ** CAPI3REF: Obtain Aggregate Function Context
4913 ** METHOD: sqlite3_context
4914 **
4915 ** Implementations of aggregate SQL functions use this
4916 ** routine to allocate memory for storing their state.
4917 **
4918 ** ^The first time the sqlite3_aggregate_context(C,N) routine is called
4919 ** for a particular aggregate function, SQLite
4920 ** allocates N of memory, zeroes out that memory, and returns a pointer
4921 ** to the new memory. ^On second and subsequent calls to
4922 ** sqlite3_aggregate_context() for the same aggregate function instance,
4923 ** the same buffer is returned.  Sqlite3_aggregate_context() is normally
4924 ** called once for each invocation of the xStep callback and then one
4925 ** last time when the xFinal callback is invoked.  ^(When no rows match
4926 ** an aggregate query, the xStep() callback of the aggregate function
4927 ** implementation is never called and xFinal() is called exactly once.
4928 ** In those cases, sqlite3_aggregate_context() might be called for the
4929 ** first time from within xFinal().)^
4930 **
4931 ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer
4932 ** when first called if N is less than or equal to zero or if a memory
4933 ** allocate error occurs.
4934 **
4935 ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
4936 ** determined by the N parameter on first successful call.  Changing the
4937 ** value of N in subsequent call to sqlite3_aggregate_context() within
4938 ** the same aggregate function instance will not resize the memory
4939 ** allocation.)^  Within the xFinal callback, it is customary to set
4940 ** N=0 in calls to sqlite3_aggregate_context(C,N) so that no
4941 ** pointless memory allocations occur.
4942 **
4943 ** ^SQLite automatically frees the memory allocated by
4944 ** sqlite3_aggregate_context() when the aggregate query concludes.
4945 **
4946 ** The first parameter must be a copy of the
4947 ** [sqlite3_context | SQL function context] that is the first parameter
4948 ** to the xStep or xFinal callback routine that implements the aggregate
4949 ** function.
4950 **
4951 ** This routine must be called from the same thread in which
4952 ** the aggregate SQL function is running.
4953 */
4954 void* sqlite3_aggregate_context(sqlite3_context*, int nBytes);
4955 
4956 /*
4957 ** CAPI3REF: User Data For Functions
4958 ** METHOD: sqlite3_context
4959 **
4960 ** ^The sqlite3_user_data() interface returns a copy of
4961 ** the pointer that was the pUserData parameter (the 5th parameter)
4962 ** of the [sqlite3_create_function()]
4963 ** and [sqlite3_create_function16()] routines that originally
4964 ** registered the application defined function.
4965 **
4966 ** This routine must be called from the same thread in which
4967 ** the application-defined function is running.
4968 */
4969 void* sqlite3_user_data(sqlite3_context*);
4970 
4971 /*
4972 ** CAPI3REF: Database Connection For Functions
4973 ** METHOD: sqlite3_context
4974 **
4975 ** ^The sqlite3_context_db_handle() interface returns a copy of
4976 ** the pointer to the [database connection] (the 1st parameter)
4977 ** of the [sqlite3_create_function()]
4978 ** and [sqlite3_create_function16()] routines that originally
4979 ** registered the application defined function.
4980 */
4981 sqlite3* sqlite3_context_db_handle(sqlite3_context*);
4982 
4983 /*
4984 ** CAPI3REF: Function Auxiliary Data
4985 ** METHOD: sqlite3_context
4986 **
4987 ** These functions may be used by (non-aggregate) SQL functions to
4988 ** associate metadata with argument values. If the same value is passed to
4989 ** multiple invocations of the same SQL function during query execution, under
4990 ** some circumstances the associated metadata may be preserved.  An example
4991 ** of where this might be useful is in a regular-expression matching
4992 ** function. The compiled version of the regular expression can be stored as
4993 ** metadata associated with the pattern string.
4994 ** Then as long as the pattern string remains the same,
4995 ** the compiled regular expression can be reused on multiple
4996 ** invocations of the same function.
4997 **
4998 ** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the metadata
4999 ** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument
5000 ** value to the application-defined function.  ^N is zero for the left-most
5001 ** function argument.  ^If there is no metadata
5002 ** associated with the function argument, the sqlite3_get_auxdata(C,N) interface
5003 ** returns a NULL pointer.
5004 **
5005 ** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
5006 ** argument of the application-defined function.  ^Subsequent
5007 ** calls to sqlite3_get_auxdata(C,N) return P from the most recent
5008 ** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
5009 ** NULL if the metadata has been discarded.
5010 ** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
5011 ** SQLite will invoke the destructor function X with parameter P exactly
5012 ** once, when the metadata is discarded.
5013 ** SQLite is free to discard the metadata at any time, including: <ul>
5014 ** <li> ^(when the corresponding function parameter changes)^, or
5015 ** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
5016 **      SQL statement)^, or
5017 ** <li> ^(when sqlite3_set_auxdata() is invoked again on the same
5018 **       parameter)^, or
5019 ** <li> ^(during the original sqlite3_set_auxdata() call when a memory
5020 **      allocation error occurs.)^ </ul>
5021 **
5022 ** Note the last bullet in particular.  The destructor X in
5023 ** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
5024 ** sqlite3_set_auxdata() interface even returns.  Hence sqlite3_set_auxdata()
5025 ** should be called near the end of the function implementation and the
5026 ** function implementation should not make any use of P after
5027 ** sqlite3_set_auxdata() has been called.
5028 **
5029 ** ^(In practice, metadata is preserved between function calls for
5030 ** function parameters that are compile-time constants, including literal
5031 ** values and [parameters] and expressions composed from the same.)^
5032 **
5033 ** The value of the N parameter to these interfaces should be non-negative.
5034 ** Future enhancements may make use of negative N values to define new
5035 ** kinds of function caching behavior.
5036 **
5037 ** These routines must be called from the same thread in which
5038 ** the SQL function is running.
5039 */
5040 void* sqlite3_get_auxdata(sqlite3_context*, int N);
5041 void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void function(void*));
5042 
5043 /*
5044 ** CAPI3REF: Constants Defining Special Destructor Behavior
5045 **
5046 ** These are special values for the destructor that is passed in as the
5047 ** final argument to routines like [sqlite3_result_blob()].  ^If the destructor
5048 ** argument is SQLITE_STATIC, it means that the content pointer is constant
5049 ** and will never change.  It does not need to be destroyed.  ^The
5050 ** SQLITE_TRANSIENT value means that the content will likely change in
5051 ** the near future and that SQLite should make its own private copy of
5052 ** the content before returning.
5053 **
5054 ** The typedef is necessary to work around problems in certain
5055 ** C++ compilers.
5056 */
5057 alias sqlite3_destructor_type = void function(void*);
5058 enum SQLITE_STATIC = cast(sqlite3_destructor_type) 0;
5059 enum SQLITE_TRANSIENT = cast(sqlite3_destructor_type) -1;
5060 
5061 /*
5062 ** CAPI3REF: Setting The Result Of An SQL Function
5063 ** METHOD: sqlite3_context
5064 **
5065 ** These routines are used by the xFunc or xFinal callbacks that
5066 ** implement SQL functions and aggregates.  See
5067 ** [sqlite3_create_function()] and [sqlite3_create_function16()]
5068 ** for additional information.
5069 **
5070 ** These functions work very much like the [parameter binding] family of
5071 ** functions used to bind values to host parameters in prepared statements.
5072 ** Refer to the [SQL parameter] documentation for additional information.
5073 **
5074 ** ^The sqlite3_result_blob() interface sets the result from
5075 ** an application-defined function to be the BLOB whose content is pointed
5076 ** to by the second parameter and which is N bytes long where N is the
5077 ** third parameter.
5078 **
5079 ** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N)
5080 ** interfaces set the result of the application-defined function to be
5081 ** a BLOB containing all zero bytes and N bytes in size.
5082 **
5083 ** ^The sqlite3_result_double() interface sets the result from
5084 ** an application-defined function to be a floating point value specified
5085 ** by its 2nd argument.
5086 **
5087 ** ^The sqlite3_result_error() and sqlite3_result_error16() functions
5088 ** cause the implemented SQL function to throw an exception.
5089 ** ^SQLite uses the string pointed to by the
5090 ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
5091 ** as the text of an error message.  ^SQLite interprets the error
5092 ** message string from sqlite3_result_error() as UTF-8. ^SQLite
5093 ** interprets the string from sqlite3_result_error16() as UTF-16 in native
5094 ** byte order.  ^If the third parameter to sqlite3_result_error()
5095 ** or sqlite3_result_error16() is negative then SQLite takes as the error
5096 ** message all text up through the first zero character.
5097 ** ^If the third parameter to sqlite3_result_error() or
5098 ** sqlite3_result_error16() is non-negative then SQLite takes that many
5099 ** bytes (not characters) from the 2nd parameter as the error message.
5100 ** ^The sqlite3_result_error() and sqlite3_result_error16()
5101 ** routines make a private copy of the error message text before
5102 ** they return.  Hence, the calling function can deallocate or
5103 ** modify the text after they return without harm.
5104 ** ^The sqlite3_result_error_code() function changes the error code
5105 ** returned by SQLite as a result of an error in a function.  ^By default,
5106 ** the error code is SQLITE_ERROR.  ^A subsequent call to sqlite3_result_error()
5107 ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
5108 **
5109 ** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
5110 ** error indicating that a string or BLOB is too long to represent.
5111 **
5112 ** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
5113 ** error indicating that a memory allocation failed.
5114 **
5115 ** ^The sqlite3_result_int() interface sets the return value
5116 ** of the application-defined function to be the 32-bit signed integer
5117 ** value given in the 2nd argument.
5118 ** ^The sqlite3_result_int64() interface sets the return value
5119 ** of the application-defined function to be the 64-bit signed integer
5120 ** value given in the 2nd argument.
5121 **
5122 ** ^The sqlite3_result_null() interface sets the return value
5123 ** of the application-defined function to be NULL.
5124 **
5125 ** ^The sqlite3_result_text(), sqlite3_result_text16(),
5126 ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
5127 ** set the return value of the application-defined function to be
5128 ** a text string which is represented as UTF-8, UTF-16 native byte order,
5129 ** UTF-16 little endian, or UTF-16 big endian, respectively.
5130 ** ^The sqlite3_result_text64() interface sets the return value of an
5131 ** application-defined function to be a text string in an encoding
5132 ** specified by the fifth (and last) parameter, which must be one
5133 ** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
5134 ** ^SQLite takes the text result from the application from
5135 ** the 2nd parameter of the sqlite3_result_text* interfaces.
5136 ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
5137 ** is negative, then SQLite takes result text from the 2nd parameter
5138 ** through the first zero character.
5139 ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
5140 ** is non-negative, then as many bytes (not characters) of the text
5141 ** pointed to by the 2nd parameter are taken as the application-defined
5142 ** function result.  If the 3rd parameter is non-negative, then it
5143 ** must be the byte offset into the string where the NUL terminator would
5144 ** appear if the string where NUL terminated.  If any NUL characters occur
5145 ** in the string at a byte offset that is less than the value of the 3rd
5146 ** parameter, then the resulting string will contain embedded NULs and the
5147 ** result of expressions operating on strings with embedded NULs is undefined.
5148 ** ^If the 4th parameter to the sqlite3_result_text* interfaces
5149 ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
5150 ** function as the destructor on the text or BLOB result when it has
5151 ** finished using that result.
5152 ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
5153 ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
5154 ** assumes that the text or BLOB result is in constant space and does not
5155 ** copy the content of the parameter nor call a destructor on the content
5156 ** when it has finished using that result.
5157 ** ^If the 4th parameter to the sqlite3_result_text* interfaces
5158 ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
5159 ** then SQLite makes a copy of the result into space obtained
5160 ** from [sqlite3_malloc()] before it returns.
5161 **
5162 ** ^The sqlite3_result_value() interface sets the result of
5163 ** the application-defined function to be a copy of the
5164 ** [unprotected sqlite3_value] object specified by the 2nd parameter.  ^The
5165 ** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
5166 ** so that the [sqlite3_value] specified in the parameter may change or
5167 ** be deallocated after sqlite3_result_value() returns without harm.
5168 ** ^A [protected sqlite3_value] object may always be used where an
5169 ** [unprotected sqlite3_value] object is required, so either
5170 ** kind of [sqlite3_value] object can be used with this interface.
5171 **
5172 ** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an
5173 ** SQL NULL value, just like [sqlite3_result_null(C)], except that it
5174 ** also associates the host-language pointer P or type T with that
5175 ** NULL value such that the pointer can be retrieved within an
5176 ** [application-defined SQL function] using [sqlite3_value_pointer()].
5177 ** ^If the D parameter is not NULL, then it is a pointer to a destructor
5178 ** for the P parameter.  ^SQLite invokes D with P as its only argument
5179 ** when SQLite is finished with P.  The T parameter should be a static
5180 ** string and preferably a string literal. The sqlite3_result_pointer()
5181 ** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
5182 **
5183 ** If these routines are called from within the different thread
5184 ** than the one containing the application-defined function that received
5185 ** the [sqlite3_context] pointer, the results are undefined.
5186 */
5187 void sqlite3_result_blob(sqlite3_context*, const(void)*, int, void function(void*));
5188 void sqlite3_result_blob64(
5189     sqlite3_context*,
5190     const(void)*,
5191     sqlite3_uint64,
5192     void function(void*));
5193 void sqlite3_result_double(sqlite3_context*, double);
5194 void sqlite3_result_error(sqlite3_context*, const(char)*, int);
5195 void sqlite3_result_error16(sqlite3_context*, const(void)*, int);
5196 void sqlite3_result_error_toobig(sqlite3_context*);
5197 void sqlite3_result_error_nomem(sqlite3_context*);
5198 void sqlite3_result_error_code(sqlite3_context*, int);
5199 void sqlite3_result_int(sqlite3_context*, int);
5200 void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
5201 void sqlite3_result_null(sqlite3_context*);
5202 void sqlite3_result_text(sqlite3_context*, const(char)*, int, void function(void*));
5203 void sqlite3_result_text64(
5204     sqlite3_context*,
5205     const(char)*,
5206     sqlite3_uint64,
5207     void function(void*),
5208     ubyte encoding);
5209 void sqlite3_result_text16(sqlite3_context*, const(void)*, int, void function(void*));
5210 void sqlite3_result_text16le(sqlite3_context*, const(void)*, int, void function(void*));
5211 void sqlite3_result_text16be(sqlite3_context*, const(void)*, int, void function(void*));
5212 void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
5213 void sqlite3_result_pointer(sqlite3_context*, void*, const(char)*, void function(void*));
5214 void sqlite3_result_zeroblob(sqlite3_context*, int n);
5215 int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n);
5216 
5217 /*
5218 ** CAPI3REF: Setting The Subtype Of An SQL Function
5219 ** METHOD: sqlite3_context
5220 **
5221 ** The sqlite3_result_subtype(C,T) function causes the subtype of
5222 ** the result from the [application-defined SQL function] with
5223 ** [sqlite3_context] C to be the value T.  Only the lower 8 bits
5224 ** of the subtype T are preserved in current versions of SQLite;
5225 ** higher order bits are discarded.
5226 ** The number of subtype bytes preserved by SQLite might increase
5227 ** in future releases of SQLite.
5228 */
5229 void sqlite3_result_subtype(sqlite3_context*, uint);
5230 
5231 /*
5232 ** CAPI3REF: Define New Collating Sequences
5233 ** METHOD: sqlite3
5234 **
5235 ** ^These functions add, remove, or modify a [collation] associated
5236 ** with the [database connection] specified as the first argument.
5237 **
5238 ** ^The name of the collation is a UTF-8 string
5239 ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
5240 ** and a UTF-16 string in native byte order for sqlite3_create_collation16().
5241 ** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
5242 ** considered to be the same name.
5243 **
5244 ** ^(The third argument (eTextRep) must be one of the constants:
5245 ** <ul>
5246 ** <li> [SQLITE_UTF8],
5247 ** <li> [SQLITE_UTF16LE],
5248 ** <li> [SQLITE_UTF16BE],
5249 ** <li> [SQLITE_UTF16], or
5250 ** <li> [SQLITE_UTF16_ALIGNED].
5251 ** </ul>)^
5252 ** ^The eTextRep argument determines the encoding of strings passed
5253 ** to the collating function callback, xCallback.
5254 ** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
5255 ** force strings to be UTF16 with native byte order.
5256 ** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
5257 ** on an even byte address.
5258 **
5259 ** ^The fourth argument, pArg, is an application data pointer that is passed
5260 ** through as the first argument to the collating function callback.
5261 **
5262 ** ^The fifth argument, xCallback, is a pointer to the collating function.
5263 ** ^Multiple collating functions can be registered using the same name but
5264 ** with different eTextRep parameters and SQLite will use whichever
5265 ** function requires the least amount of data transformation.
5266 ** ^If the xCallback argument is NULL then the collating function is
5267 ** deleted.  ^When all collating functions having the same name are deleted,
5268 ** that collation is no longer usable.
5269 **
5270 ** ^The collating function callback is invoked with a copy of the pArg
5271 ** application data pointer and with two strings in the encoding specified
5272 ** by the eTextRep argument.  The collating function must return an
5273 ** integer that is negative, zero, or positive
5274 ** if the first string is less than, equal to, or greater than the second,
5275 ** respectively.  A collating function must always return the same answer
5276 ** given the same inputs.  If two or more collating functions are registered
5277 ** to the same collation name (using different eTextRep values) then all
5278 ** must give an equivalent answer when invoked with equivalent strings.
5279 ** The collating function must obey the following properties for all
5280 ** strings A, B, and C:
5281 **
5282 ** <ol>
5283 ** <li> If A==B then B==A.
5284 ** <li> If A==B and B==C then A==C.
5285 ** <li> If A&lt;B THEN B&gt;A.
5286 ** <li> If A&lt;B and B&lt;C then A&lt;C.
5287 ** </ol>
5288 **
5289 ** If a collating function fails any of the above constraints and that
5290 ** collating function is  registered and used, then the behavior of SQLite
5291 ** is undefined.
5292 **
5293 ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
5294 ** with the addition that the xDestroy callback is invoked on pArg when
5295 ** the collating function is deleted.
5296 ** ^Collating functions are deleted when they are overridden by later
5297 ** calls to the collation creation functions or when the
5298 ** [database connection] is closed using [sqlite3_close()].
5299 **
5300 ** ^The xDestroy callback is <u>not</u> called if the
5301 ** sqlite3_create_collation_v2() function fails.  Applications that invoke
5302 ** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
5303 ** check the return code and dispose of the application data pointer
5304 ** themselves rather than expecting SQLite to deal with it for them.
5305 ** This is different from every other SQLite interface.  The inconsistency
5306 ** is unfortunate but cannot be changed without breaking backwards
5307 ** compatibility.
5308 **
5309 ** See also:  [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
5310 */
5311 int sqlite3_create_collation(
5312     sqlite3*,
5313     const(char)* zName,
5314     int eTextRep,
5315     void* pArg,
5316     int function(void*, int, const(void)*, int, const(void)*) xCompare);
5317 int sqlite3_create_collation_v2(
5318     sqlite3*,
5319     const(char)* zName,
5320     int eTextRep,
5321     void* pArg,
5322     int function(void*, int, const(void)*, int, const(void)*) xCompare,
5323     void function(void*) xDestroy);
5324 int sqlite3_create_collation16(
5325     sqlite3*,
5326     const(void)* zName,
5327     int eTextRep,
5328     void* pArg,
5329     int function(void*, int, const(void)*, int, const(void)*) xCompare);
5330 
5331 /*
5332 ** CAPI3REF: Collation Needed Callbacks
5333 ** METHOD: sqlite3
5334 **
5335 ** ^To avoid having to register all collation sequences before a database
5336 ** can be used, a single callback function may be registered with the
5337 ** [database connection] to be invoked whenever an undefined collation
5338 ** sequence is required.
5339 **
5340 ** ^If the function is registered using the sqlite3_collation_needed() API,
5341 ** then it is passed the names of undefined collation sequences as strings
5342 ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
5343 ** the names are passed as UTF-16 in machine native byte order.
5344 ** ^A call to either function replaces the existing collation-needed callback.
5345 **
5346 ** ^(When the callback is invoked, the first argument passed is a copy
5347 ** of the second argument to sqlite3_collation_needed() or
5348 ** sqlite3_collation_needed16().  The second argument is the database
5349 ** connection.  The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
5350 ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
5351 ** sequence function required.  The fourth parameter is the name of the
5352 ** required collation sequence.)^
5353 **
5354 ** The callback function should register the desired collation using
5355 ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
5356 ** [sqlite3_create_collation_v2()].
5357 */
5358 int sqlite3_collation_needed(
5359     sqlite3*,
5360     void*,
5361     void function(void*, sqlite3*, int eTextRep, const(char)*));
5362 int sqlite3_collation_needed16(
5363     sqlite3*,
5364     void*,
5365     void function(void*, sqlite3*, int eTextRep, const(void)*));
5366 
5367 /*
5368 ** Specify the key for an encrypted database.  This routine should be
5369 ** called right after sqlite3_open().
5370 **
5371 ** The code to implement this API is not available in the public release
5372 ** of SQLite.
5373 */
5374 
5375 /* Database to be rekeyed */
5376 /* The key */
5377 
5378 /* Database to be rekeyed */
5379 /* Name of the database */
5380 /* The key */
5381 
5382 /*
5383 ** Change the key on an open database.  If the current database is not
5384 ** encrypted, this routine will encrypt it.  If pNew==0 or nNew==0, the
5385 ** database is decrypted.
5386 **
5387 ** The code to implement this API is not available in the public release
5388 ** of SQLite.
5389 */
5390 
5391 /* Database to be rekeyed */
5392 /* The new key */
5393 
5394 /* Database to be rekeyed */
5395 /* Name of the database */
5396 /* The new key */
5397 
5398 /*
5399 ** Specify the activation key for a SEE database.  Unless
5400 ** activated, none of the SEE routines will work.
5401 */
5402 
5403 /* Activation phrase */
5404 
5405 /*
5406 ** Specify the activation key for a CEROD database.  Unless
5407 ** activated, none of the CEROD routines will work.
5408 */
5409 
5410 /* Activation phrase */
5411 
5412 /*
5413 ** CAPI3REF: Suspend Execution For A Short Time
5414 **
5415 ** The sqlite3_sleep() function causes the current thread to suspend execution
5416 ** for at least a number of milliseconds specified in its parameter.
5417 **
5418 ** If the operating system does not support sleep requests with
5419 ** millisecond time resolution, then the time will be rounded up to
5420 ** the nearest second. The number of milliseconds of sleep actually
5421 ** requested from the operating system is returned.
5422 **
5423 ** ^SQLite implements this interface by calling the xSleep()
5424 ** method of the default [sqlite3_vfs] object.  If the xSleep() method
5425 ** of the default VFS is not implemented correctly, or not implemented at
5426 ** all, then the behavior of sqlite3_sleep() may deviate from the description
5427 ** in the previous paragraphs.
5428 */
5429 int sqlite3_sleep(int);
5430 
5431 /*
5432 ** CAPI3REF: Name Of The Folder Holding Temporary Files
5433 **
5434 ** ^(If this global variable is made to point to a string which is
5435 ** the name of a folder (a.k.a. directory), then all temporary files
5436 ** created by SQLite when using a built-in [sqlite3_vfs | VFS]
5437 ** will be placed in that directory.)^  ^If this variable
5438 ** is a NULL pointer, then SQLite performs a search for an appropriate
5439 ** temporary file directory.
5440 **
5441 ** Applications are strongly discouraged from using this global variable.
5442 ** It is required to set a temporary folder on Windows Runtime (WinRT).
5443 ** But for all other platforms, it is highly recommended that applications
5444 ** neither read nor write this variable.  This global variable is a relic
5445 ** that exists for backwards compatibility of legacy applications and should
5446 ** be avoided in new projects.
5447 **
5448 ** It is not safe to read or modify this variable in more than one
5449 ** thread at a time.  It is not safe to read or modify this variable
5450 ** if a [database connection] is being used at the same time in a separate
5451 ** thread.
5452 ** It is intended that this variable be set once
5453 ** as part of process initialization and before any SQLite interface
5454 ** routines have been called and that this variable remain unchanged
5455 ** thereafter.
5456 **
5457 ** ^The [temp_store_directory pragma] may modify this variable and cause
5458 ** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
5459 ** the [temp_store_directory pragma] always assumes that any string
5460 ** that this variable points to is held in memory obtained from
5461 ** [sqlite3_malloc] and the pragma may attempt to free that memory
5462 ** using [sqlite3_free].
5463 ** Hence, if this variable is modified directly, either it should be
5464 ** made NULL or made to point to memory obtained from [sqlite3_malloc]
5465 ** or else the use of the [temp_store_directory pragma] should be avoided.
5466 ** Except when requested by the [temp_store_directory pragma], SQLite
5467 ** does not free the memory that sqlite3_temp_directory points to.  If
5468 ** the application wants that memory to be freed, it must do
5469 ** so itself, taking care to only do so after all [database connection]
5470 ** objects have been destroyed.
5471 **
5472 ** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
5473 ** prior to calling [sqlite3_open] or [sqlite3_open_v2].  Otherwise, various
5474 ** features that require the use of temporary files may fail.  Here is an
5475 ** example of how to do this using C++ with the Windows Runtime:
5476 **
5477 ** <blockquote><pre>
5478 ** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
5479 ** &nbsp;     TemporaryFolder->Path->Data();
5480 ** char zPathBuf&#91;MAX_PATH + 1&#93;;
5481 ** memset(zPathBuf, 0, sizeof(zPathBuf));
5482 ** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
5483 ** &nbsp;     NULL, NULL);
5484 ** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
5485 ** </pre></blockquote>
5486 */
5487 extern __gshared char* sqlite3_temp_directory;
5488 
5489 /*
5490 ** CAPI3REF: Name Of The Folder Holding Database Files
5491 **
5492 ** ^(If this global variable is made to point to a string which is
5493 ** the name of a folder (a.k.a. directory), then all database files
5494 ** specified with a relative pathname and created or accessed by
5495 ** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
5496 ** to be relative to that directory.)^ ^If this variable is a NULL
5497 ** pointer, then SQLite assumes that all database files specified
5498 ** with a relative pathname are relative to the current directory
5499 ** for the process.  Only the windows VFS makes use of this global
5500 ** variable; it is ignored by the unix VFS.
5501 **
5502 ** Changing the value of this variable while a database connection is
5503 ** open can result in a corrupt database.
5504 **
5505 ** It is not safe to read or modify this variable in more than one
5506 ** thread at a time.  It is not safe to read or modify this variable
5507 ** if a [database connection] is being used at the same time in a separate
5508 ** thread.
5509 ** It is intended that this variable be set once
5510 ** as part of process initialization and before any SQLite interface
5511 ** routines have been called and that this variable remain unchanged
5512 ** thereafter.
5513 **
5514 ** ^The [data_store_directory pragma] may modify this variable and cause
5515 ** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
5516 ** the [data_store_directory pragma] always assumes that any string
5517 ** that this variable points to is held in memory obtained from
5518 ** [sqlite3_malloc] and the pragma may attempt to free that memory
5519 ** using [sqlite3_free].
5520 ** Hence, if this variable is modified directly, either it should be
5521 ** made NULL or made to point to memory obtained from [sqlite3_malloc]
5522 ** or else the use of the [data_store_directory pragma] should be avoided.
5523 */
5524 extern __gshared char* sqlite3_data_directory;
5525 
5526 /*
5527 ** CAPI3REF: Test For Auto-Commit Mode
5528 ** KEYWORDS: {autocommit mode}
5529 ** METHOD: sqlite3
5530 **
5531 ** ^The sqlite3_get_autocommit() interface returns non-zero or
5532 ** zero if the given database connection is or is not in autocommit mode,
5533 ** respectively.  ^Autocommit mode is on by default.
5534 ** ^Autocommit mode is disabled by a [BEGIN] statement.
5535 ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
5536 **
5537 ** If certain kinds of errors occur on a statement within a multi-statement
5538 ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
5539 ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
5540 ** transaction might be rolled back automatically.  The only way to
5541 ** find out whether SQLite automatically rolled back the transaction after
5542 ** an error is to use this function.
5543 **
5544 ** If another thread changes the autocommit status of the database
5545 ** connection while this routine is running, then the return value
5546 ** is undefined.
5547 */
5548 int sqlite3_get_autocommit(sqlite3*);
5549 
5550 /*
5551 ** CAPI3REF: Find The Database Handle Of A Prepared Statement
5552 ** METHOD: sqlite3_stmt
5553 **
5554 ** ^The sqlite3_db_handle interface returns the [database connection] handle
5555 ** to which a [prepared statement] belongs.  ^The [database connection]
5556 ** returned by sqlite3_db_handle is the same [database connection]
5557 ** that was the first argument
5558 ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
5559 ** create the statement in the first place.
5560 */
5561 sqlite3* sqlite3_db_handle(sqlite3_stmt*);
5562 
5563 /*
5564 ** CAPI3REF: Return The Filename For A Database Connection
5565 ** METHOD: sqlite3
5566 **
5567 ** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename
5568 ** associated with database N of connection D.  ^The main database file
5569 ** has the name "main".  If there is no attached database N on the database
5570 ** connection D, or if database N is a temporary or in-memory database, then
5571 ** a NULL pointer is returned.
5572 **
5573 ** ^The filename returned by this function is the output of the
5574 ** xFullPathname method of the [VFS].  ^In other words, the filename
5575 ** will be an absolute pathname, even if the filename used
5576 ** to open the database originally was a URI or relative pathname.
5577 */
5578 const(char)* sqlite3_db_filename(sqlite3* db, const(char)* zDbName);
5579 
5580 /*
5581 ** CAPI3REF: Determine if a database is read-only
5582 ** METHOD: sqlite3
5583 **
5584 ** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
5585 ** of connection D is read-only, 0 if it is read/write, or -1 if N is not
5586 ** the name of a database on connection D.
5587 */
5588 int sqlite3_db_readonly(sqlite3* db, const(char)* zDbName);
5589 
5590 /*
5591 ** CAPI3REF: Find the next prepared statement
5592 ** METHOD: sqlite3
5593 **
5594 ** ^This interface returns a pointer to the next [prepared statement] after
5595 ** pStmt associated with the [database connection] pDb.  ^If pStmt is NULL
5596 ** then this interface returns a pointer to the first prepared statement
5597 ** associated with the database connection pDb.  ^If no prepared statement
5598 ** satisfies the conditions of this routine, it returns NULL.
5599 **
5600 ** The [database connection] pointer D in a call to
5601 ** [sqlite3_next_stmt(D,S)] must refer to an open database
5602 ** connection and in particular must not be a NULL pointer.
5603 */
5604 sqlite3_stmt* sqlite3_next_stmt(sqlite3* pDb, sqlite3_stmt* pStmt);
5605 
5606 /*
5607 ** CAPI3REF: Commit And Rollback Notification Callbacks
5608 ** METHOD: sqlite3
5609 **
5610 ** ^The sqlite3_commit_hook() interface registers a callback
5611 ** function to be invoked whenever a transaction is [COMMIT | committed].
5612 ** ^Any callback set by a previous call to sqlite3_commit_hook()
5613 ** for the same database connection is overridden.
5614 ** ^The sqlite3_rollback_hook() interface registers a callback
5615 ** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
5616 ** ^Any callback set by a previous call to sqlite3_rollback_hook()
5617 ** for the same database connection is overridden.
5618 ** ^The pArg argument is passed through to the callback.
5619 ** ^If the callback on a commit hook function returns non-zero,
5620 ** then the commit is converted into a rollback.
5621 **
5622 ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
5623 ** return the P argument from the previous call of the same function
5624 ** on the same [database connection] D, or NULL for
5625 ** the first call for each function on D.
5626 **
5627 ** The commit and rollback hook callbacks are not reentrant.
5628 ** The callback implementation must not do anything that will modify
5629 ** the database connection that invoked the callback.  Any actions
5630 ** to modify the database connection must be deferred until after the
5631 ** completion of the [sqlite3_step()] call that triggered the commit
5632 ** or rollback hook in the first place.
5633 ** Note that running any other SQL statements, including SELECT statements,
5634 ** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
5635 ** the database connections for the meaning of "modify" in this paragraph.
5636 **
5637 ** ^Registering a NULL function disables the callback.
5638 **
5639 ** ^When the commit hook callback routine returns zero, the [COMMIT]
5640 ** operation is allowed to continue normally.  ^If the commit hook
5641 ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
5642 ** ^The rollback hook is invoked on a rollback that results from a commit
5643 ** hook returning non-zero, just as it would be with any other rollback.
5644 **
5645 ** ^For the purposes of this API, a transaction is said to have been
5646 ** rolled back if an explicit "ROLLBACK" statement is executed, or
5647 ** an error or constraint causes an implicit rollback to occur.
5648 ** ^The rollback callback is not invoked if a transaction is
5649 ** automatically rolled back because the database connection is closed.
5650 **
5651 ** See also the [sqlite3_update_hook()] interface.
5652 */
5653 void* sqlite3_commit_hook(sqlite3*, int function(void*), void*);
5654 void* sqlite3_rollback_hook(sqlite3*, void function(void*), void*);
5655 
5656 /*
5657 ** CAPI3REF: Data Change Notification Callbacks
5658 ** METHOD: sqlite3
5659 **
5660 ** ^The sqlite3_update_hook() interface registers a callback function
5661 ** with the [database connection] identified by the first argument
5662 ** to be invoked whenever a row is updated, inserted or deleted in
5663 ** a [rowid table].
5664 ** ^Any callback set by a previous call to this function
5665 ** for the same database connection is overridden.
5666 **
5667 ** ^The second argument is a pointer to the function to invoke when a
5668 ** row is updated, inserted or deleted in a rowid table.
5669 ** ^The first argument to the callback is a copy of the third argument
5670 ** to sqlite3_update_hook().
5671 ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
5672 ** or [SQLITE_UPDATE], depending on the operation that caused the callback
5673 ** to be invoked.
5674 ** ^The third and fourth arguments to the callback contain pointers to the
5675 ** database and table name containing the affected row.
5676 ** ^The final callback parameter is the [rowid] of the row.
5677 ** ^In the case of an update, this is the [rowid] after the update takes place.
5678 **
5679 ** ^(The update hook is not invoked when internal system tables are
5680 ** modified (i.e. sqlite_master and sqlite_sequence).)^
5681 ** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
5682 **
5683 ** ^In the current implementation, the update hook
5684 ** is not invoked when conflicting rows are deleted because of an
5685 ** [ON CONFLICT | ON CONFLICT REPLACE] clause.  ^Nor is the update hook
5686 ** invoked when rows are deleted using the [truncate optimization].
5687 ** The exceptions defined in this paragraph might change in a future
5688 ** release of SQLite.
5689 **
5690 ** The update hook implementation must not do anything that will modify
5691 ** the database connection that invoked the update hook.  Any actions
5692 ** to modify the database connection must be deferred until after the
5693 ** completion of the [sqlite3_step()] call that triggered the update hook.
5694 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
5695 ** database connections for the meaning of "modify" in this paragraph.
5696 **
5697 ** ^The sqlite3_update_hook(D,C,P) function
5698 ** returns the P argument from the previous call
5699 ** on the same [database connection] D, or NULL for
5700 ** the first call on D.
5701 **
5702 ** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()],
5703 ** and [sqlite3_preupdate_hook()] interfaces.
5704 */
5705 void* sqlite3_update_hook(
5706     sqlite3*,
5707     void function(void*, int, const(char)*, const(char)*, sqlite3_int64),
5708     void*);
5709 
5710 /*
5711 ** CAPI3REF: Enable Or Disable Shared Pager Cache
5712 **
5713 ** ^(This routine enables or disables the sharing of the database cache
5714 ** and schema data structures between [database connection | connections]
5715 ** to the same database. Sharing is enabled if the argument is true
5716 ** and disabled if the argument is false.)^
5717 **
5718 ** ^Cache sharing is enabled and disabled for an entire process.
5719 ** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]).
5720 ** In prior versions of SQLite,
5721 ** sharing was enabled or disabled for each thread separately.
5722 **
5723 ** ^(The cache sharing mode set by this interface effects all subsequent
5724 ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
5725 ** Existing database connections continue use the sharing mode
5726 ** that was in effect at the time they were opened.)^
5727 **
5728 ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
5729 ** successfully.  An [error code] is returned otherwise.)^
5730 **
5731 ** ^Shared cache is disabled by default. But this might change in
5732 ** future releases of SQLite.  Applications that care about shared
5733 ** cache setting should set it explicitly.
5734 **
5735 ** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0
5736 ** and will always return SQLITE_MISUSE. On those systems,
5737 ** shared cache mode should be enabled per-database connection via
5738 ** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE].
5739 **
5740 ** This interface is threadsafe on processors where writing a
5741 ** 32-bit integer is atomic.
5742 **
5743 ** See Also:  [SQLite Shared-Cache Mode]
5744 */
5745 int sqlite3_enable_shared_cache(int);
5746 
5747 /*
5748 ** CAPI3REF: Attempt To Free Heap Memory
5749 **
5750 ** ^The sqlite3_release_memory() interface attempts to free N bytes
5751 ** of heap memory by deallocating non-essential memory allocations
5752 ** held by the database library.   Memory used to cache database
5753 ** pages to improve performance is an example of non-essential memory.
5754 ** ^sqlite3_release_memory() returns the number of bytes actually freed,
5755 ** which might be more or less than the amount requested.
5756 ** ^The sqlite3_release_memory() routine is a no-op returning zero
5757 ** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
5758 **
5759 ** See also: [sqlite3_db_release_memory()]
5760 */
5761 int sqlite3_release_memory(int);
5762 
5763 /*
5764 ** CAPI3REF: Free Memory Used By A Database Connection
5765 ** METHOD: sqlite3
5766 **
5767 ** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
5768 ** memory as possible from database connection D. Unlike the
5769 ** [sqlite3_release_memory()] interface, this interface is in effect even
5770 ** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
5771 ** omitted.
5772 **
5773 ** See also: [sqlite3_release_memory()]
5774 */
5775 int sqlite3_db_release_memory(sqlite3*);
5776 
5777 /*
5778 ** CAPI3REF: Impose A Limit On Heap Size
5779 **
5780 ** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
5781 ** soft limit on the amount of heap memory that may be allocated by SQLite.
5782 ** ^SQLite strives to keep heap memory utilization below the soft heap
5783 ** limit by reducing the number of pages held in the page cache
5784 ** as heap memory usages approaches the limit.
5785 ** ^The soft heap limit is "soft" because even though SQLite strives to stay
5786 ** below the limit, it will exceed the limit rather than generate
5787 ** an [SQLITE_NOMEM] error.  In other words, the soft heap limit
5788 ** is advisory only.
5789 **
5790 ** ^The return value from sqlite3_soft_heap_limit64() is the size of
5791 ** the soft heap limit prior to the call, or negative in the case of an
5792 ** error.  ^If the argument N is negative
5793 ** then no change is made to the soft heap limit.  Hence, the current
5794 ** size of the soft heap limit can be determined by invoking
5795 ** sqlite3_soft_heap_limit64() with a negative argument.
5796 **
5797 ** ^If the argument N is zero then the soft heap limit is disabled.
5798 **
5799 ** ^(The soft heap limit is not enforced in the current implementation
5800 ** if one or more of following conditions are true:
5801 **
5802 ** <ul>
5803 ** <li> The soft heap limit is set to zero.
5804 ** <li> Memory accounting is disabled using a combination of the
5805 **      [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
5806 **      the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
5807 ** <li> An alternative page cache implementation is specified using
5808 **      [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
5809 ** <li> The page cache allocates from its own memory pool supplied
5810 **      by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
5811 **      from the heap.
5812 ** </ul>)^
5813 **
5814 ** Beginning with SQLite [version 3.7.3] ([dateof:3.7.3]),
5815 ** the soft heap limit is enforced
5816 ** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
5817 ** compile-time option is invoked.  With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
5818 ** the soft heap limit is enforced on every memory allocation.  Without
5819 ** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
5820 ** when memory is allocated by the page cache.  Testing suggests that because
5821 ** the page cache is the predominate memory user in SQLite, most
5822 ** applications will achieve adequate soft heap limit enforcement without
5823 ** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
5824 **
5825 ** The circumstances under which SQLite will enforce the soft heap limit may
5826 ** changes in future releases of SQLite.
5827 */
5828 sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
5829 
5830 /*
5831 ** CAPI3REF: Deprecated Soft Heap Limit Interface
5832 ** DEPRECATED
5833 **
5834 ** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
5835 ** interface.  This routine is provided for historical compatibility
5836 ** only.  All new applications should use the
5837 ** [sqlite3_soft_heap_limit64()] interface rather than this one.
5838 */
5839 void sqlite3_soft_heap_limit(int N);
5840 
5841 /*
5842 ** CAPI3REF: Extract Metadata About A Column Of A Table
5843 ** METHOD: sqlite3
5844 **
5845 ** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns
5846 ** information about column C of table T in database D
5847 ** on [database connection] X.)^  ^The sqlite3_table_column_metadata()
5848 ** interface returns SQLITE_OK and fills in the non-NULL pointers in
5849 ** the final five arguments with appropriate values if the specified
5850 ** column exists.  ^The sqlite3_table_column_metadata() interface returns
5851 ** SQLITE_ERROR and if the specified column does not exist.
5852 ** ^If the column-name parameter to sqlite3_table_column_metadata() is a
5853 ** NULL pointer, then this routine simply checks for the existence of the
5854 ** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it
5855 ** does not.  If the table name parameter T in a call to
5856 ** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is
5857 ** undefined behavior.
5858 **
5859 ** ^The column is identified by the second, third and fourth parameters to
5860 ** this function. ^(The second parameter is either the name of the database
5861 ** (i.e. "main", "temp", or an attached database) containing the specified
5862 ** table or NULL.)^ ^If it is NULL, then all attached databases are searched
5863 ** for the table using the same algorithm used by the database engine to
5864 ** resolve unqualified table references.
5865 **
5866 ** ^The third and fourth parameters to this function are the table and column
5867 ** name of the desired column, respectively.
5868 **
5869 ** ^Metadata is returned by writing to the memory locations passed as the 5th
5870 ** and subsequent parameters to this function. ^Any of these arguments may be
5871 ** NULL, in which case the corresponding element of metadata is omitted.
5872 **
5873 ** ^(<blockquote>
5874 ** <table border="1">
5875 ** <tr><th> Parameter <th> Output<br>Type <th>  Description
5876 **
5877 ** <tr><td> 5th <td> const char* <td> Data type
5878 ** <tr><td> 6th <td> const char* <td> Name of default collation sequence
5879 ** <tr><td> 7th <td> int         <td> True if column has a NOT NULL constraint
5880 ** <tr><td> 8th <td> int         <td> True if column is part of the PRIMARY KEY
5881 ** <tr><td> 9th <td> int         <td> True if column is [AUTOINCREMENT]
5882 ** </table>
5883 ** </blockquote>)^
5884 **
5885 ** ^The memory pointed to by the character pointers returned for the
5886 ** declaration type and collation sequence is valid until the next
5887 ** call to any SQLite API function.
5888 **
5889 ** ^If the specified table is actually a view, an [error code] is returned.
5890 **
5891 ** ^If the specified column is "rowid", "oid" or "_rowid_" and the table
5892 ** is not a [WITHOUT ROWID] table and an
5893 ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
5894 ** parameters are set for the explicitly declared column. ^(If there is no
5895 ** [INTEGER PRIMARY KEY] column, then the outputs
5896 ** for the [rowid] are set as follows:
5897 **
5898 ** <pre>
5899 **     data type: "INTEGER"
5900 **     collation sequence: "BINARY"
5901 **     not null: 0
5902 **     primary key: 1
5903 **     auto increment: 0
5904 ** </pre>)^
5905 **
5906 ** ^This function causes all database schemas to be read from disk and
5907 ** parsed, if that has not already been done, and returns an error if
5908 ** any errors are encountered while loading the schema.
5909 */
5910 /* Connection handle */
5911 /* Database name or NULL */
5912 /* Table name */
5913 /* Column name */
5914 /* OUTPUT: Declared data type */
5915 /* OUTPUT: Collation sequence name */
5916 /* OUTPUT: True if NOT NULL constraint exists */
5917 /* OUTPUT: True if column part of PK */
5918 /* OUTPUT: True if column is auto-increment */
5919 int sqlite3_table_column_metadata(
5920     sqlite3* db,
5921     const(char)* zDbName,
5922     const(char)* zTableName,
5923     const(char)* zColumnName,
5924     const(char*)* pzDataType,
5925     const(char*)* pzCollSeq,
5926     int* pNotNull,
5927     int* pPrimaryKey,
5928     int* pAutoinc);
5929 
5930 /*
5931 ** CAPI3REF: Load An Extension
5932 ** METHOD: sqlite3
5933 **
5934 ** ^This interface loads an SQLite extension library from the named file.
5935 **
5936 ** ^The sqlite3_load_extension() interface attempts to load an
5937 ** [SQLite extension] library contained in the file zFile.  If
5938 ** the file cannot be loaded directly, attempts are made to load
5939 ** with various operating-system specific extensions added.
5940 ** So for example, if "samplelib" cannot be loaded, then names like
5941 ** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
5942 ** be tried also.
5943 **
5944 ** ^The entry point is zProc.
5945 ** ^(zProc may be 0, in which case SQLite will try to come up with an
5946 ** entry point name on its own.  It first tries "sqlite3_extension_init".
5947 ** If that does not work, it constructs a name "sqlite3_X_init" where the
5948 ** X is consists of the lower-case equivalent of all ASCII alphabetic
5949 ** characters in the filename from the last "/" to the first following
5950 ** "." and omitting any initial "lib".)^
5951 ** ^The sqlite3_load_extension() interface returns
5952 ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
5953 ** ^If an error occurs and pzErrMsg is not 0, then the
5954 ** [sqlite3_load_extension()] interface shall attempt to
5955 ** fill *pzErrMsg with error message text stored in memory
5956 ** obtained from [sqlite3_malloc()]. The calling function
5957 ** should free this memory by calling [sqlite3_free()].
5958 **
5959 ** ^Extension loading must be enabled using
5960 ** [sqlite3_enable_load_extension()] or
5961 ** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL)
5962 ** prior to calling this API,
5963 ** otherwise an error will be returned.
5964 **
5965 ** <b>Security warning:</b> It is recommended that the
5966 ** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this
5967 ** interface.  The use of the [sqlite3_enable_load_extension()] interface
5968 ** should be avoided.  This will keep the SQL function [load_extension()]
5969 ** disabled and prevent SQL injections from giving attackers
5970 ** access to extension loading capabilities.
5971 **
5972 ** See also the [load_extension() SQL function].
5973 */
5974 /* Load the extension into this database connection */
5975 /* Name of the shared library containing extension */
5976 /* Entry point.  Derived from zFile if 0 */
5977 /* Put error message here if not 0 */
5978 int sqlite3_load_extension(
5979     sqlite3* db,
5980     const(char)* zFile,
5981     const(char)* zProc,
5982     char** pzErrMsg);
5983 
5984 /*
5985 ** CAPI3REF: Enable Or Disable Extension Loading
5986 ** METHOD: sqlite3
5987 **
5988 ** ^So as not to open security holes in older applications that are
5989 ** unprepared to deal with [extension loading], and as a means of disabling
5990 ** [extension loading] while evaluating user-entered SQL, the following API
5991 ** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
5992 **
5993 ** ^Extension loading is off by default.
5994 ** ^Call the sqlite3_enable_load_extension() routine with onoff==1
5995 ** to turn extension loading on and call it with onoff==0 to turn
5996 ** it back off again.
5997 **
5998 ** ^This interface enables or disables both the C-API
5999 ** [sqlite3_load_extension()] and the SQL function [load_extension()].
6000 ** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..)
6001 ** to enable or disable only the C-API.)^
6002 **
6003 ** <b>Security warning:</b> It is recommended that extension loading
6004 ** be disabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method
6005 ** rather than this interface, so the [load_extension()] SQL function
6006 ** remains disabled. This will prevent SQL injections from giving attackers
6007 ** access to extension loading capabilities.
6008 */
6009 int sqlite3_enable_load_extension(sqlite3* db, int onoff);
6010 
6011 /*
6012 ** CAPI3REF: Automatically Load Statically Linked Extensions
6013 **
6014 ** ^This interface causes the xEntryPoint() function to be invoked for
6015 ** each new [database connection] that is created.  The idea here is that
6016 ** xEntryPoint() is the entry point for a statically linked [SQLite extension]
6017 ** that is to be automatically loaded into all new database connections.
6018 **
6019 ** ^(Even though the function prototype shows that xEntryPoint() takes
6020 ** no arguments and returns void, SQLite invokes xEntryPoint() with three
6021 ** arguments and expects an integer result as if the signature of the
6022 ** entry point where as follows:
6023 **
6024 ** <blockquote><pre>
6025 ** &nbsp;  int xEntryPoint(
6026 ** &nbsp;    sqlite3 *db,
6027 ** &nbsp;    const char **pzErrMsg,
6028 ** &nbsp;    const struct sqlite3_api_routines *pThunk
6029 ** &nbsp;  );
6030 ** </pre></blockquote>)^
6031 **
6032 ** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
6033 ** point to an appropriate error message (obtained from [sqlite3_mprintf()])
6034 ** and return an appropriate [error code].  ^SQLite ensures that *pzErrMsg
6035 ** is NULL before calling the xEntryPoint().  ^SQLite will invoke
6036 ** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns.  ^If any
6037 ** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
6038 ** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
6039 **
6040 ** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
6041 ** on the list of automatic extensions is a harmless no-op. ^No entry point
6042 ** will be called more than once for each database connection that is opened.
6043 **
6044 ** See also: [sqlite3_reset_auto_extension()]
6045 ** and [sqlite3_cancel_auto_extension()]
6046 */
6047 int sqlite3_auto_extension(void function() xEntryPoint);
6048 
6049 /*
6050 ** CAPI3REF: Cancel Automatic Extension Loading
6051 **
6052 ** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
6053 ** initialization routine X that was registered using a prior call to
6054 ** [sqlite3_auto_extension(X)].  ^The [sqlite3_cancel_auto_extension(X)]
6055 ** routine returns 1 if initialization routine X was successfully
6056 ** unregistered and it returns 0 if X was not on the list of initialization
6057 ** routines.
6058 */
6059 int sqlite3_cancel_auto_extension(void function() xEntryPoint);
6060 
6061 /*
6062 ** CAPI3REF: Reset Automatic Extension Loading
6063 **
6064 ** ^This interface disables all automatic extensions previously
6065 ** registered using [sqlite3_auto_extension()].
6066 */
6067 void sqlite3_reset_auto_extension();
6068 
6069 /*
6070 ** The interface to the virtual-table mechanism is currently considered
6071 ** to be experimental.  The interface might change in incompatible ways.
6072 ** If this is a problem for you, do not use the interface at this time.
6073 **
6074 ** When the virtual-table mechanism stabilizes, we will declare the
6075 ** interface fixed, support it indefinitely, and remove this comment.
6076 */
6077 
6078 /*
6079 ** Structures used by the virtual table interface
6080 */
6081 
6082 /*
6083 ** CAPI3REF: Virtual Table Object
6084 ** KEYWORDS: sqlite3_module {virtual table module}
6085 **
6086 ** This structure, sometimes called a "virtual table module",
6087 ** defines the implementation of a [virtual tables].
6088 ** This structure consists mostly of methods for the module.
6089 **
6090 ** ^A virtual table module is created by filling in a persistent
6091 ** instance of this structure and passing a pointer to that instance
6092 ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
6093 ** ^The registration remains valid until it is replaced by a different
6094 ** module or until the [database connection] closes.  The content
6095 ** of this structure must not change while it is registered with
6096 ** any database connection.
6097 */
6098 struct sqlite3_module
6099 {
6100     int iVersion;
6101     int function(sqlite3*, void* pAux, int argc, const(char*)* argv, sqlite3_vtab** ppVTab, char**) xCreate;
6102     int function(sqlite3*, void* pAux, int argc, const(char*)* argv, sqlite3_vtab** ppVTab, char**) xConnect;
6103     int function(sqlite3_vtab* pVTab, sqlite3_index_info*) xBestIndex;
6104     int function(sqlite3_vtab* pVTab) xDisconnect;
6105     int function(sqlite3_vtab* pVTab) xDestroy;
6106     int function(sqlite3_vtab* pVTab, sqlite3_vtab_cursor** ppCursor) xOpen;
6107     int function(sqlite3_vtab_cursor*) xClose;
6108     int function(sqlite3_vtab_cursor*, int idxNum, const(char)* idxStr, int argc, sqlite3_value** argv) xFilter;
6109     int function(sqlite3_vtab_cursor*) xNext;
6110     int function(sqlite3_vtab_cursor*) xEof;
6111     int function(sqlite3_vtab_cursor*, sqlite3_context*, int) xColumn;
6112     int function(sqlite3_vtab_cursor*, sqlite3_int64* pRowid) xRowid;
6113     int function(sqlite3_vtab*, int, sqlite3_value**, sqlite3_int64*) xUpdate;
6114     int function(sqlite3_vtab* pVTab) xBegin;
6115     int function(sqlite3_vtab* pVTab) xSync;
6116     int function(sqlite3_vtab* pVTab) xCommit;
6117     int function(sqlite3_vtab* pVTab) xRollback;
6118     int function(sqlite3_vtab* pVtab, int nArg, const(char)* zName, void function(sqlite3_context*, int, sqlite3_value**)* pxFunc, void** ppArg) xFindFunction;
6119     int function(sqlite3_vtab* pVtab, const(char)* zNew) xRename;
6120     /* The methods above are in version 1 of the sqlite_module object. Those
6121     ** below are for version 2 and greater. */
6122     int function(sqlite3_vtab* pVTab, int) xSavepoint;
6123     int function(sqlite3_vtab* pVTab, int) xRelease;
6124     int function(sqlite3_vtab* pVTab, int) xRollbackTo;
6125 }
6126 
6127 /*
6128 ** CAPI3REF: Virtual Table Indexing Information
6129 ** KEYWORDS: sqlite3_index_info
6130 **
6131 ** The sqlite3_index_info structure and its substructures is used as part
6132 ** of the [virtual table] interface to
6133 ** pass information into and receive the reply from the [xBestIndex]
6134 ** method of a [virtual table module].  The fields under **Inputs** are the
6135 ** inputs to xBestIndex and are read-only.  xBestIndex inserts its
6136 ** results into the **Outputs** fields.
6137 **
6138 ** ^(The aConstraint[] array records WHERE clause constraints of the form:
6139 **
6140 ** <blockquote>column OP expr</blockquote>
6141 **
6142 ** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.)^  ^(The particular operator is
6143 ** stored in aConstraint[].op using one of the
6144 ** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
6145 ** ^(The index of the column is stored in
6146 ** aConstraint[].iColumn.)^  ^(aConstraint[].usable is TRUE if the
6147 ** expr on the right-hand side can be evaluated (and thus the constraint
6148 ** is usable) and false if it cannot.)^
6149 **
6150 ** ^The optimizer automatically inverts terms of the form "expr OP column"
6151 ** and makes other simplifications to the WHERE clause in an attempt to
6152 ** get as many WHERE clause terms into the form shown above as possible.
6153 ** ^The aConstraint[] array only reports WHERE clause terms that are
6154 ** relevant to the particular virtual table being queried.
6155 **
6156 ** ^Information about the ORDER BY clause is stored in aOrderBy[].
6157 ** ^Each term of aOrderBy records a column of the ORDER BY clause.
6158 **
6159 ** The colUsed field indicates which columns of the virtual table may be
6160 ** required by the current scan. Virtual table columns are numbered from
6161 ** zero in the order in which they appear within the CREATE TABLE statement
6162 ** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62),
6163 ** the corresponding bit is set within the colUsed mask if the column may be
6164 ** required by SQLite. If the table has at least 64 columns and any column
6165 ** to the right of the first 63 is required, then bit 63 of colUsed is also
6166 ** set. In other words, column iCol may be required if the expression
6167 ** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to
6168 ** non-zero.
6169 **
6170 ** The [xBestIndex] method must fill aConstraintUsage[] with information
6171 ** about what parameters to pass to xFilter.  ^If argvIndex>0 then
6172 ** the right-hand side of the corresponding aConstraint[] is evaluated
6173 ** and becomes the argvIndex-th entry in argv.  ^(If aConstraintUsage[].omit
6174 ** is true, then the constraint is assumed to be fully handled by the
6175 ** virtual table and is not checked again by SQLite.)^
6176 **
6177 ** ^The idxNum and idxPtr values are recorded and passed into the
6178 ** [xFilter] method.
6179 ** ^[sqlite3_free()] is used to free idxPtr if and only if
6180 ** needToFreeIdxPtr is true.
6181 **
6182 ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
6183 ** the correct order to satisfy the ORDER BY clause so that no separate
6184 ** sorting step is required.
6185 **
6186 ** ^The estimatedCost value is an estimate of the cost of a particular
6187 ** strategy. A cost of N indicates that the cost of the strategy is similar
6188 ** to a linear scan of an SQLite table with N rows. A cost of log(N)
6189 ** indicates that the expense of the operation is similar to that of a
6190 ** binary search on a unique indexed field of an SQLite table with N rows.
6191 **
6192 ** ^The estimatedRows value is an estimate of the number of rows that
6193 ** will be returned by the strategy.
6194 **
6195 ** The xBestIndex method may optionally populate the idxFlags field with a
6196 ** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag -
6197 ** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite
6198 ** assumes that the strategy may visit at most one row.
6199 **
6200 ** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then
6201 ** SQLite also assumes that if a call to the xUpdate() method is made as
6202 ** part of the same statement to delete or update a virtual table row and the
6203 ** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback
6204 ** any database changes. In other words, if the xUpdate() returns
6205 ** SQLITE_CONSTRAINT, the database contents must be exactly as they were
6206 ** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not
6207 ** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by
6208 ** the xUpdate method are automatically rolled back by SQLite.
6209 **
6210 ** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
6211 ** structure for SQLite [version 3.8.2] ([dateof:3.8.2]).
6212 ** If a virtual table extension is
6213 ** used with an SQLite version earlier than 3.8.2, the results of attempting
6214 ** to read or write the estimatedRows field are undefined (but are likely
6215 ** to included crashing the application). The estimatedRows field should
6216 ** therefore only be used if [sqlite3_libversion_number()] returns a
6217 ** value greater than or equal to 3008002. Similarly, the idxFlags field
6218 ** was added for [version 3.9.0] ([dateof:3.9.0]).
6219 ** It may therefore only be used if
6220 ** sqlite3_libversion_number() returns a value greater than or equal to
6221 ** 3009000.
6222 */
6223 struct sqlite3_index_info
6224 {
6225     /* Inputs */
6226     int nConstraint; /* Number of entries in aConstraint */
6227 
6228     /* Column constrained.  -1 for ROWID */
6229     /* Constraint operator */
6230     /* True if this constraint is usable */
6231     /* Used internally - xBestIndex should ignore */
6232     struct sqlite3_index_constraint
6233     {
6234         int iColumn;
6235         ubyte op;
6236         ubyte usable;
6237         int iTermOffset;
6238     }
6239 
6240     sqlite3_index_constraint* aConstraint; /* Table of WHERE clause constraints */
6241     int nOrderBy; /* Number of terms in the ORDER BY clause */
6242 
6243     /* Column number */
6244     /* True for DESC.  False for ASC. */
6245     struct sqlite3_index_orderby
6246     {
6247         int iColumn;
6248         ubyte desc;
6249     }
6250 
6251     sqlite3_index_orderby* aOrderBy; /* The ORDER BY clause */
6252     /* Outputs */
6253 
6254     /* if >0, constraint is part of argv to xFilter */
6255     /* Do not code a test for this constraint */
6256     struct sqlite3_index_constraint_usage
6257     {
6258         int argvIndex;
6259         ubyte omit;
6260     }
6261 
6262     sqlite3_index_constraint_usage* aConstraintUsage;
6263     int idxNum; /* Number used to identify the index */
6264     char* idxStr; /* String, possibly obtained from sqlite3_malloc */
6265     int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
6266     int orderByConsumed; /* True if output is already ordered */
6267     double estimatedCost; /* Estimated cost of using this index */
6268     /* Fields below are only available in SQLite 3.8.2 and later */
6269     sqlite3_int64 estimatedRows; /* Estimated number of rows returned */
6270     /* Fields below are only available in SQLite 3.9.0 and later */
6271     int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */
6272     /* Fields below are only available in SQLite 3.10.0 and later */
6273     sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */
6274 }
6275 
6276 /*
6277 ** CAPI3REF: Virtual Table Scan Flags
6278 */
6279 enum SQLITE_INDEX_SCAN_UNIQUE = 1; /* Scan visits at most 1 row */
6280 
6281 /*
6282 ** CAPI3REF: Virtual Table Constraint Operator Codes
6283 **
6284 ** These macros defined the allowed values for the
6285 ** [sqlite3_index_info].aConstraint[].op field.  Each value represents
6286 ** an operator that is part of a constraint term in the wHERE clause of
6287 ** a query that uses a [virtual table].
6288 */
6289 enum SQLITE_INDEX_CONSTRAINT_EQ = 2;
6290 enum SQLITE_INDEX_CONSTRAINT_GT = 4;
6291 enum SQLITE_INDEX_CONSTRAINT_LE = 8;
6292 enum SQLITE_INDEX_CONSTRAINT_LT = 16;
6293 enum SQLITE_INDEX_CONSTRAINT_GE = 32;
6294 enum SQLITE_INDEX_CONSTRAINT_MATCH = 64;
6295 enum SQLITE_INDEX_CONSTRAINT_LIKE = 65;
6296 enum SQLITE_INDEX_CONSTRAINT_GLOB = 66;
6297 enum SQLITE_INDEX_CONSTRAINT_REGEXP = 67;
6298 enum SQLITE_INDEX_CONSTRAINT_NE = 68;
6299 enum SQLITE_INDEX_CONSTRAINT_ISNOT = 69;
6300 enum SQLITE_INDEX_CONSTRAINT_ISNOTNULL = 70;
6301 enum SQLITE_INDEX_CONSTRAINT_ISNULL = 71;
6302 enum SQLITE_INDEX_CONSTRAINT_IS = 72;
6303 
6304 /*
6305 ** CAPI3REF: Register A Virtual Table Implementation
6306 ** METHOD: sqlite3
6307 **
6308 ** ^These routines are used to register a new [virtual table module] name.
6309 ** ^Module names must be registered before
6310 ** creating a new [virtual table] using the module and before using a
6311 ** preexisting [virtual table] for the module.
6312 **
6313 ** ^The module name is registered on the [database connection] specified
6314 ** by the first parameter.  ^The name of the module is given by the
6315 ** second parameter.  ^The third parameter is a pointer to
6316 ** the implementation of the [virtual table module].   ^The fourth
6317 ** parameter is an arbitrary client data pointer that is passed through
6318 ** into the [xCreate] and [xConnect] methods of the virtual table module
6319 ** when a new virtual table is be being created or reinitialized.
6320 **
6321 ** ^The sqlite3_create_module_v2() interface has a fifth parameter which
6322 ** is a pointer to a destructor for the pClientData.  ^SQLite will
6323 ** invoke the destructor function (if it is not NULL) when SQLite
6324 ** no longer needs the pClientData pointer.  ^The destructor will also
6325 ** be invoked if the call to sqlite3_create_module_v2() fails.
6326 ** ^The sqlite3_create_module()
6327 ** interface is equivalent to sqlite3_create_module_v2() with a NULL
6328 ** destructor.
6329 */
6330 /* SQLite connection to register module with */
6331 /* Name of the module */
6332 /* Methods for the module */
6333 /* Client data for xCreate/xConnect */
6334 int sqlite3_create_module(
6335     sqlite3* db,
6336     const(char)* zName,
6337     const(sqlite3_module)* p,
6338     void* pClientData);
6339 
6340 /* SQLite connection to register module with */
6341 /* Name of the module */
6342 /* Methods for the module */
6343 /* Client data for xCreate/xConnect */
6344 /* Module destructor function */
6345 int sqlite3_create_module_v2(
6346     sqlite3* db,
6347     const(char)* zName,
6348     const(sqlite3_module)* p,
6349     void* pClientData,
6350     void function(void*) xDestroy);
6351 
6352 /*
6353 ** CAPI3REF: Virtual Table Instance Object
6354 ** KEYWORDS: sqlite3_vtab
6355 **
6356 ** Every [virtual table module] implementation uses a subclass
6357 ** of this object to describe a particular instance
6358 ** of the [virtual table].  Each subclass will
6359 ** be tailored to the specific needs of the module implementation.
6360 ** The purpose of this superclass is to define certain fields that are
6361 ** common to all module implementations.
6362 **
6363 ** ^Virtual tables methods can set an error message by assigning a
6364 ** string obtained from [sqlite3_mprintf()] to zErrMsg.  The method should
6365 ** take care that any prior string is freed by a call to [sqlite3_free()]
6366 ** prior to assigning a new string to zErrMsg.  ^After the error message
6367 ** is delivered up to the client application, the string will be automatically
6368 ** freed by sqlite3_free() and the zErrMsg field will be zeroed.
6369 */
6370 struct sqlite3_vtab
6371 {
6372     const(sqlite3_module)* pModule; /* The module for this virtual table */
6373     int nRef; /* Number of open cursors */
6374     char* zErrMsg; /* Error message from sqlite3_mprintf() */
6375     /* Virtual table implementations will typically add additional fields */
6376 }
6377 
6378 /*
6379 ** CAPI3REF: Virtual Table Cursor Object
6380 ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
6381 **
6382 ** Every [virtual table module] implementation uses a subclass of the
6383 ** following structure to describe cursors that point into the
6384 ** [virtual table] and are used
6385 ** to loop through the virtual table.  Cursors are created using the
6386 ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
6387 ** by the [sqlite3_module.xClose | xClose] method.  Cursors are used
6388 ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
6389 ** of the module.  Each module implementation will define
6390 ** the content of a cursor structure to suit its own needs.
6391 **
6392 ** This superclass exists in order to define fields of the cursor that
6393 ** are common to all implementations.
6394 */
6395 struct sqlite3_vtab_cursor
6396 {
6397     sqlite3_vtab* pVtab; /* Virtual table of this cursor */
6398     /* Virtual table implementations will typically add additional fields */
6399 }
6400 
6401 /*
6402 ** CAPI3REF: Declare The Schema Of A Virtual Table
6403 **
6404 ** ^The [xCreate] and [xConnect] methods of a
6405 ** [virtual table module] call this interface
6406 ** to declare the format (the names and datatypes of the columns) of
6407 ** the virtual tables they implement.
6408 */
6409 int sqlite3_declare_vtab(sqlite3*, const(char)* zSQL);
6410 
6411 /*
6412 ** CAPI3REF: Overload A Function For A Virtual Table
6413 ** METHOD: sqlite3
6414 **
6415 ** ^(Virtual tables can provide alternative implementations of functions
6416 ** using the [xFindFunction] method of the [virtual table module].
6417 ** But global versions of those functions
6418 ** must exist in order to be overloaded.)^
6419 **
6420 ** ^(This API makes sure a global version of a function with a particular
6421 ** name and number of parameters exists.  If no such function exists
6422 ** before this API is called, a new function is created.)^  ^The implementation
6423 ** of the new function always causes an exception to be thrown.  So
6424 ** the new function is not good for anything by itself.  Its only
6425 ** purpose is to be a placeholder function that can be overloaded
6426 ** by a [virtual table].
6427 */
6428 int sqlite3_overload_function(sqlite3*, const(char)* zFuncName, int nArg);
6429 
6430 /*
6431 ** The interface to the virtual-table mechanism defined above (back up
6432 ** to a comment remarkably similar to this one) is currently considered
6433 ** to be experimental.  The interface might change in incompatible ways.
6434 ** If this is a problem for you, do not use the interface at this time.
6435 **
6436 ** When the virtual-table mechanism stabilizes, we will declare the
6437 ** interface fixed, support it indefinitely, and remove this comment.
6438 */
6439 
6440 /*
6441 ** CAPI3REF: A Handle To An Open BLOB
6442 ** KEYWORDS: {BLOB handle} {BLOB handles}
6443 **
6444 ** An instance of this object represents an open BLOB on which
6445 ** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
6446 ** ^Objects of this type are created by [sqlite3_blob_open()]
6447 ** and destroyed by [sqlite3_blob_close()].
6448 ** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
6449 ** can be used to read or write small subsections of the BLOB.
6450 ** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
6451 */
6452 struct sqlite3_blob;
6453 
6454 /*
6455 ** CAPI3REF: Open A BLOB For Incremental I/O
6456 ** METHOD: sqlite3
6457 ** CONSTRUCTOR: sqlite3_blob
6458 **
6459 ** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
6460 ** in row iRow, column zColumn, table zTable in database zDb;
6461 ** in other words, the same BLOB that would be selected by:
6462 **
6463 ** <pre>
6464 **     SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
6465 ** </pre>)^
6466 **
6467 ** ^(Parameter zDb is not the filename that contains the database, but
6468 ** rather the symbolic name of the database. For attached databases, this is
6469 ** the name that appears after the AS keyword in the [ATTACH] statement.
6470 ** For the main database file, the database name is "main". For TEMP
6471 ** tables, the database name is "temp".)^
6472 **
6473 ** ^If the flags parameter is non-zero, then the BLOB is opened for read
6474 ** and write access. ^If the flags parameter is zero, the BLOB is opened for
6475 ** read-only access.
6476 **
6477 ** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored
6478 ** in *ppBlob. Otherwise an [error code] is returned and, unless the error
6479 ** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided
6480 ** the API is not misused, it is always safe to call [sqlite3_blob_close()]
6481 ** on *ppBlob after this function it returns.
6482 **
6483 ** This function fails with SQLITE_ERROR if any of the following are true:
6484 ** <ul>
6485 **   <li> ^(Database zDb does not exist)^,
6486 **   <li> ^(Table zTable does not exist within database zDb)^,
6487 **   <li> ^(Table zTable is a WITHOUT ROWID table)^,
6488 **   <li> ^(Column zColumn does not exist)^,
6489 **   <li> ^(Row iRow is not present in the table)^,
6490 **   <li> ^(The specified column of row iRow contains a value that is not
6491 **         a TEXT or BLOB value)^,
6492 **   <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE
6493 **         constraint and the blob is being opened for read/write access)^,
6494 **   <li> ^([foreign key constraints | Foreign key constraints] are enabled,
6495 **         column zColumn is part of a [child key] definition and the blob is
6496 **         being opened for read/write access)^.
6497 ** </ul>
6498 **
6499 ** ^Unless it returns SQLITE_MISUSE, this function sets the
6500 ** [database connection] error code and message accessible via
6501 ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
6502 **
6503 ** A BLOB referenced by sqlite3_blob_open() may be read using the
6504 ** [sqlite3_blob_read()] interface and modified by using
6505 ** [sqlite3_blob_write()].  The [BLOB handle] can be moved to a
6506 ** different row of the same table using the [sqlite3_blob_reopen()]
6507 ** interface.  However, the column, table, or database of a [BLOB handle]
6508 ** cannot be changed after the [BLOB handle] is opened.
6509 **
6510 ** ^(If the row that a BLOB handle points to is modified by an
6511 ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
6512 ** then the BLOB handle is marked as "expired".
6513 ** This is true if any column of the row is changed, even a column
6514 ** other than the one the BLOB handle is open on.)^
6515 ** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
6516 ** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
6517 ** ^(Changes written into a BLOB prior to the BLOB expiring are not
6518 ** rolled back by the expiration of the BLOB.  Such changes will eventually
6519 ** commit if the transaction continues to completion.)^
6520 **
6521 ** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
6522 ** the opened blob.  ^The size of a blob may not be changed by this
6523 ** interface.  Use the [UPDATE] SQL command to change the size of a
6524 ** blob.
6525 **
6526 ** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
6527 ** and the built-in [zeroblob] SQL function may be used to create a
6528 ** zero-filled blob to read or write using the incremental-blob interface.
6529 **
6530 ** To avoid a resource leak, every open [BLOB handle] should eventually
6531 ** be released by a call to [sqlite3_blob_close()].
6532 **
6533 ** See also: [sqlite3_blob_close()],
6534 ** [sqlite3_blob_reopen()], [sqlite3_blob_read()],
6535 ** [sqlite3_blob_bytes()], [sqlite3_blob_write()].
6536 */
6537 int sqlite3_blob_open(
6538     sqlite3*,
6539     const(char)* zDb,
6540     const(char)* zTable,
6541     const(char)* zColumn,
6542     sqlite3_int64 iRow,
6543     int flags,
6544     sqlite3_blob** ppBlob);
6545 
6546 /*
6547 ** CAPI3REF: Move a BLOB Handle to a New Row
6548 ** METHOD: sqlite3_blob
6549 **
6550 ** ^This function is used to move an existing [BLOB handle] so that it points
6551 ** to a different row of the same database table. ^The new row is identified
6552 ** by the rowid value passed as the second argument. Only the row can be
6553 ** changed. ^The database, table and column on which the blob handle is open
6554 ** remain the same. Moving an existing [BLOB handle] to a new row is
6555 ** faster than closing the existing handle and opening a new one.
6556 **
6557 ** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
6558 ** it must exist and there must be either a blob or text value stored in
6559 ** the nominated column.)^ ^If the new row is not present in the table, or if
6560 ** it does not contain a blob or text value, or if another error occurs, an
6561 ** SQLite error code is returned and the blob handle is considered aborted.
6562 ** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
6563 ** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
6564 ** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
6565 ** always returns zero.
6566 **
6567 ** ^This function sets the database handle error code and message.
6568 */
6569 int sqlite3_blob_reopen(sqlite3_blob*, sqlite3_int64);
6570 
6571 /*
6572 ** CAPI3REF: Close A BLOB Handle
6573 ** DESTRUCTOR: sqlite3_blob
6574 **
6575 ** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed
6576 ** unconditionally.  Even if this routine returns an error code, the
6577 ** handle is still closed.)^
6578 **
6579 ** ^If the blob handle being closed was opened for read-write access, and if
6580 ** the database is in auto-commit mode and there are no other open read-write
6581 ** blob handles or active write statements, the current transaction is
6582 ** committed. ^If an error occurs while committing the transaction, an error
6583 ** code is returned and the transaction rolled back.
6584 **
6585 ** Calling this function with an argument that is not a NULL pointer or an
6586 ** open blob handle results in undefined behaviour. ^Calling this routine
6587 ** with a null pointer (such as would be returned by a failed call to
6588 ** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function
6589 ** is passed a valid open blob handle, the values returned by the
6590 ** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning.
6591 */
6592 int sqlite3_blob_close(sqlite3_blob*);
6593 
6594 /*
6595 ** CAPI3REF: Return The Size Of An Open BLOB
6596 ** METHOD: sqlite3_blob
6597 **
6598 ** ^Returns the size in bytes of the BLOB accessible via the
6599 ** successfully opened [BLOB handle] in its only argument.  ^The
6600 ** incremental blob I/O routines can only read or overwriting existing
6601 ** blob content; they cannot change the size of a blob.
6602 **
6603 ** This routine only works on a [BLOB handle] which has been created
6604 ** by a prior successful call to [sqlite3_blob_open()] and which has not
6605 ** been closed by [sqlite3_blob_close()].  Passing any other pointer in
6606 ** to this routine results in undefined and probably undesirable behavior.
6607 */
6608 int sqlite3_blob_bytes(sqlite3_blob*);
6609 
6610 /*
6611 ** CAPI3REF: Read Data From A BLOB Incrementally
6612 ** METHOD: sqlite3_blob
6613 **
6614 ** ^(This function is used to read data from an open [BLOB handle] into a
6615 ** caller-supplied buffer. N bytes of data are copied into buffer Z
6616 ** from the open BLOB, starting at offset iOffset.)^
6617 **
6618 ** ^If offset iOffset is less than N bytes from the end of the BLOB,
6619 ** [SQLITE_ERROR] is returned and no data is read.  ^If N or iOffset is
6620 ** less than zero, [SQLITE_ERROR] is returned and no data is read.
6621 ** ^The size of the blob (and hence the maximum value of N+iOffset)
6622 ** can be determined using the [sqlite3_blob_bytes()] interface.
6623 **
6624 ** ^An attempt to read from an expired [BLOB handle] fails with an
6625 ** error code of [SQLITE_ABORT].
6626 **
6627 ** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
6628 ** Otherwise, an [error code] or an [extended error code] is returned.)^
6629 **
6630 ** This routine only works on a [BLOB handle] which has been created
6631 ** by a prior successful call to [sqlite3_blob_open()] and which has not
6632 ** been closed by [sqlite3_blob_close()].  Passing any other pointer in
6633 ** to this routine results in undefined and probably undesirable behavior.
6634 **
6635 ** See also: [sqlite3_blob_write()].
6636 */
6637 int sqlite3_blob_read(sqlite3_blob*, void* Z, int N, int iOffset);
6638 
6639 /*
6640 ** CAPI3REF: Write Data Into A BLOB Incrementally
6641 ** METHOD: sqlite3_blob
6642 **
6643 ** ^(This function is used to write data into an open [BLOB handle] from a
6644 ** caller-supplied buffer. N bytes of data are copied from the buffer Z
6645 ** into the open BLOB, starting at offset iOffset.)^
6646 **
6647 ** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
6648 ** Otherwise, an  [error code] or an [extended error code] is returned.)^
6649 ** ^Unless SQLITE_MISUSE is returned, this function sets the
6650 ** [database connection] error code and message accessible via
6651 ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
6652 **
6653 ** ^If the [BLOB handle] passed as the first argument was not opened for
6654 ** writing (the flags parameter to [sqlite3_blob_open()] was zero),
6655 ** this function returns [SQLITE_READONLY].
6656 **
6657 ** This function may only modify the contents of the BLOB; it is
6658 ** not possible to increase the size of a BLOB using this API.
6659 ** ^If offset iOffset is less than N bytes from the end of the BLOB,
6660 ** [SQLITE_ERROR] is returned and no data is written. The size of the
6661 ** BLOB (and hence the maximum value of N+iOffset) can be determined
6662 ** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less
6663 ** than zero [SQLITE_ERROR] is returned and no data is written.
6664 **
6665 ** ^An attempt to write to an expired [BLOB handle] fails with an
6666 ** error code of [SQLITE_ABORT].  ^Writes to the BLOB that occurred
6667 ** before the [BLOB handle] expired are not rolled back by the
6668 ** expiration of the handle, though of course those changes might
6669 ** have been overwritten by the statement that expired the BLOB handle
6670 ** or by other independent statements.
6671 **
6672 ** This routine only works on a [BLOB handle] which has been created
6673 ** by a prior successful call to [sqlite3_blob_open()] and which has not
6674 ** been closed by [sqlite3_blob_close()].  Passing any other pointer in
6675 ** to this routine results in undefined and probably undesirable behavior.
6676 **
6677 ** See also: [sqlite3_blob_read()].
6678 */
6679 int sqlite3_blob_write(sqlite3_blob*, const(void)* z, int n, int iOffset);
6680 
6681 /*
6682 ** CAPI3REF: Virtual File System Objects
6683 **
6684 ** A virtual filesystem (VFS) is an [sqlite3_vfs] object
6685 ** that SQLite uses to interact
6686 ** with the underlying operating system.  Most SQLite builds come with a
6687 ** single default VFS that is appropriate for the host computer.
6688 ** New VFSes can be registered and existing VFSes can be unregistered.
6689 ** The following interfaces are provided.
6690 **
6691 ** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
6692 ** ^Names are case sensitive.
6693 ** ^Names are zero-terminated UTF-8 strings.
6694 ** ^If there is no match, a NULL pointer is returned.
6695 ** ^If zVfsName is NULL then the default VFS is returned.
6696 **
6697 ** ^New VFSes are registered with sqlite3_vfs_register().
6698 ** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
6699 ** ^The same VFS can be registered multiple times without injury.
6700 ** ^To make an existing VFS into the default VFS, register it again
6701 ** with the makeDflt flag set.  If two different VFSes with the
6702 ** same name are registered, the behavior is undefined.  If a
6703 ** VFS is registered with a name that is NULL or an empty string,
6704 ** then the behavior is undefined.
6705 **
6706 ** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
6707 ** ^(If the default VFS is unregistered, another VFS is chosen as
6708 ** the default.  The choice for the new VFS is arbitrary.)^
6709 */
6710 sqlite3_vfs* sqlite3_vfs_find(const(char)* zVfsName);
6711 int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
6712 int sqlite3_vfs_unregister(sqlite3_vfs*);
6713 
6714 /*
6715 ** CAPI3REF: Mutexes
6716 **
6717 ** The SQLite core uses these routines for thread
6718 ** synchronization. Though they are intended for internal
6719 ** use by SQLite, code that links against SQLite is
6720 ** permitted to use any of these routines.
6721 **
6722 ** The SQLite source code contains multiple implementations
6723 ** of these mutex routines.  An appropriate implementation
6724 ** is selected automatically at compile-time.  The following
6725 ** implementations are available in the SQLite core:
6726 **
6727 ** <ul>
6728 ** <li>   SQLITE_MUTEX_PTHREADS
6729 ** <li>   SQLITE_MUTEX_W32
6730 ** <li>   SQLITE_MUTEX_NOOP
6731 ** </ul>
6732 **
6733 ** The SQLITE_MUTEX_NOOP implementation is a set of routines
6734 ** that does no real locking and is appropriate for use in
6735 ** a single-threaded application.  The SQLITE_MUTEX_PTHREADS and
6736 ** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
6737 ** and Windows.
6738 **
6739 ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
6740 ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
6741 ** implementation is included with the library. In this case the
6742 ** application must supply a custom mutex implementation using the
6743 ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
6744 ** before calling sqlite3_initialize() or any other public sqlite3_
6745 ** function that calls sqlite3_initialize().
6746 **
6747 ** ^The sqlite3_mutex_alloc() routine allocates a new
6748 ** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc()
6749 ** routine returns NULL if it is unable to allocate the requested
6750 ** mutex.  The argument to sqlite3_mutex_alloc() must one of these
6751 ** integer constants:
6752 **
6753 ** <ul>
6754 ** <li>  SQLITE_MUTEX_FAST
6755 ** <li>  SQLITE_MUTEX_RECURSIVE
6756 ** <li>  SQLITE_MUTEX_STATIC_MASTER
6757 ** <li>  SQLITE_MUTEX_STATIC_MEM
6758 ** <li>  SQLITE_MUTEX_STATIC_OPEN
6759 ** <li>  SQLITE_MUTEX_STATIC_PRNG
6760 ** <li>  SQLITE_MUTEX_STATIC_LRU
6761 ** <li>  SQLITE_MUTEX_STATIC_PMEM
6762 ** <li>  SQLITE_MUTEX_STATIC_APP1
6763 ** <li>  SQLITE_MUTEX_STATIC_APP2
6764 ** <li>  SQLITE_MUTEX_STATIC_APP3
6765 ** <li>  SQLITE_MUTEX_STATIC_VFS1
6766 ** <li>  SQLITE_MUTEX_STATIC_VFS2
6767 ** <li>  SQLITE_MUTEX_STATIC_VFS3
6768 ** </ul>
6769 **
6770 ** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
6771 ** cause sqlite3_mutex_alloc() to create
6772 ** a new mutex.  ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
6773 ** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
6774 ** The mutex implementation does not need to make a distinction
6775 ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
6776 ** not want to.  SQLite will only request a recursive mutex in
6777 ** cases where it really needs one.  If a faster non-recursive mutex
6778 ** implementation is available on the host platform, the mutex subsystem
6779 ** might return such a mutex in response to SQLITE_MUTEX_FAST.
6780 **
6781 ** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
6782 ** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
6783 ** a pointer to a static preexisting mutex.  ^Nine static mutexes are
6784 ** used by the current version of SQLite.  Future versions of SQLite
6785 ** may add additional static mutexes.  Static mutexes are for internal
6786 ** use by SQLite only.  Applications that use SQLite mutexes should
6787 ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
6788 ** SQLITE_MUTEX_RECURSIVE.
6789 **
6790 ** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
6791 ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
6792 ** returns a different mutex on every call.  ^For the static
6793 ** mutex types, the same mutex is returned on every call that has
6794 ** the same type number.
6795 **
6796 ** ^The sqlite3_mutex_free() routine deallocates a previously
6797 ** allocated dynamic mutex.  Attempting to deallocate a static
6798 ** mutex results in undefined behavior.
6799 **
6800 ** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
6801 ** to enter a mutex.  ^If another thread is already within the mutex,
6802 ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
6803 ** SQLITE_BUSY.  ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
6804 ** upon successful entry.  ^(Mutexes created using
6805 ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
6806 ** In such cases, the
6807 ** mutex must be exited an equal number of times before another thread
6808 ** can enter.)^  If the same thread tries to enter any mutex other
6809 ** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined.
6810 **
6811 ** ^(Some systems (for example, Windows 95) do not support the operation
6812 ** implemented by sqlite3_mutex_try().  On those systems, sqlite3_mutex_try()
6813 ** will always return SQLITE_BUSY. The SQLite core only ever uses
6814 ** sqlite3_mutex_try() as an optimization so this is acceptable
6815 ** behavior.)^
6816 **
6817 ** ^The sqlite3_mutex_leave() routine exits a mutex that was
6818 ** previously entered by the same thread.   The behavior
6819 ** is undefined if the mutex is not currently entered by the
6820 ** calling thread or is not currently allocated.
6821 **
6822 ** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
6823 ** sqlite3_mutex_leave() is a NULL pointer, then all three routines
6824 ** behave as no-ops.
6825 **
6826 ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
6827 */
6828 sqlite3_mutex* sqlite3_mutex_alloc(int);
6829 void sqlite3_mutex_free(sqlite3_mutex*);
6830 void sqlite3_mutex_enter(sqlite3_mutex*);
6831 int sqlite3_mutex_try(sqlite3_mutex*);
6832 void sqlite3_mutex_leave(sqlite3_mutex*);
6833 
6834 /*
6835 ** CAPI3REF: Mutex Methods Object
6836 **
6837 ** An instance of this structure defines the low-level routines
6838 ** used to allocate and use mutexes.
6839 **
6840 ** Usually, the default mutex implementations provided by SQLite are
6841 ** sufficient, however the application has the option of substituting a custom
6842 ** implementation for specialized deployments or systems for which SQLite
6843 ** does not provide a suitable implementation. In this case, the application
6844 ** creates and populates an instance of this structure to pass
6845 ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
6846 ** Additionally, an instance of this structure can be used as an
6847 ** output variable when querying the system for the current mutex
6848 ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
6849 **
6850 ** ^The xMutexInit method defined by this structure is invoked as
6851 ** part of system initialization by the sqlite3_initialize() function.
6852 ** ^The xMutexInit routine is called by SQLite exactly once for each
6853 ** effective call to [sqlite3_initialize()].
6854 **
6855 ** ^The xMutexEnd method defined by this structure is invoked as
6856 ** part of system shutdown by the sqlite3_shutdown() function. The
6857 ** implementation of this method is expected to release all outstanding
6858 ** resources obtained by the mutex methods implementation, especially
6859 ** those obtained by the xMutexInit method.  ^The xMutexEnd()
6860 ** interface is invoked exactly once for each call to [sqlite3_shutdown()].
6861 **
6862 ** ^(The remaining seven methods defined by this structure (xMutexAlloc,
6863 ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
6864 ** xMutexNotheld) implement the following interfaces (respectively):
6865 **
6866 ** <ul>
6867 **   <li>  [sqlite3_mutex_alloc()] </li>
6868 **   <li>  [sqlite3_mutex_free()] </li>
6869 **   <li>  [sqlite3_mutex_enter()] </li>
6870 **   <li>  [sqlite3_mutex_try()] </li>
6871 **   <li>  [sqlite3_mutex_leave()] </li>
6872 **   <li>  [sqlite3_mutex_held()] </li>
6873 **   <li>  [sqlite3_mutex_notheld()] </li>
6874 ** </ul>)^
6875 **
6876 ** The only difference is that the public sqlite3_XXX functions enumerated
6877 ** above silently ignore any invocations that pass a NULL pointer instead
6878 ** of a valid mutex handle. The implementations of the methods defined
6879 ** by this structure are not required to handle this case, the results
6880 ** of passing a NULL pointer instead of a valid mutex handle are undefined
6881 ** (i.e. it is acceptable to provide an implementation that segfaults if
6882 ** it is passed a NULL pointer).
6883 **
6884 ** The xMutexInit() method must be threadsafe.  It must be harmless to
6885 ** invoke xMutexInit() multiple times within the same process and without
6886 ** intervening calls to xMutexEnd().  Second and subsequent calls to
6887 ** xMutexInit() must be no-ops.
6888 **
6889 ** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
6890 ** and its associates).  Similarly, xMutexAlloc() must not use SQLite memory
6891 ** allocation for a static mutex.  ^However xMutexAlloc() may use SQLite
6892 ** memory allocation for a fast or recursive mutex.
6893 **
6894 ** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
6895 ** called, but only if the prior call to xMutexInit returned SQLITE_OK.
6896 ** If xMutexInit fails in any way, it is expected to clean up after itself
6897 ** prior to returning.
6898 */
6899 struct sqlite3_mutex_methods
6900 {
6901     int function() xMutexInit;
6902     int function() xMutexEnd;
6903     sqlite3_mutex* function(int) xMutexAlloc;
6904     void function(sqlite3_mutex*) xMutexFree;
6905     void function(sqlite3_mutex*) xMutexEnter;
6906     int function(sqlite3_mutex*) xMutexTry;
6907     void function(sqlite3_mutex*) xMutexLeave;
6908     int function(sqlite3_mutex*) xMutexHeld;
6909     int function(sqlite3_mutex*) xMutexNotheld;
6910 }
6911 
6912 /*
6913 ** CAPI3REF: Mutex Verification Routines
6914 **
6915 ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
6916 ** are intended for use inside assert() statements.  The SQLite core
6917 ** never uses these routines except inside an assert() and applications
6918 ** are advised to follow the lead of the core.  The SQLite core only
6919 ** provides implementations for these routines when it is compiled
6920 ** with the SQLITE_DEBUG flag.  External mutex implementations
6921 ** are only required to provide these routines if SQLITE_DEBUG is
6922 ** defined and if NDEBUG is not defined.
6923 **
6924 ** These routines should return true if the mutex in their argument
6925 ** is held or not held, respectively, by the calling thread.
6926 **
6927 ** The implementation is not required to provide versions of these
6928 ** routines that actually work. If the implementation does not provide working
6929 ** versions of these routines, it should at least provide stubs that always
6930 ** return true so that one does not get spurious assertion failures.
6931 **
6932 ** If the argument to sqlite3_mutex_held() is a NULL pointer then
6933 ** the routine should return 1.   This seems counter-intuitive since
6934 ** clearly the mutex cannot be held if it does not exist.  But
6935 ** the reason the mutex does not exist is because the build is not
6936 ** using mutexes.  And we do not want the assert() containing the
6937 ** call to sqlite3_mutex_held() to fail, so a non-zero return is
6938 ** the appropriate thing to do.  The sqlite3_mutex_notheld()
6939 ** interface should also return 1 when given a NULL pointer.
6940 */
6941 
6942 int sqlite3_mutex_held(sqlite3_mutex*);
6943 int sqlite3_mutex_notheld(sqlite3_mutex*);
6944 
6945 /*
6946 ** CAPI3REF: Mutex Types
6947 **
6948 ** The [sqlite3_mutex_alloc()] interface takes a single argument
6949 ** which is one of these integer constants.
6950 **
6951 ** The set of static mutexes may change from one SQLite release to the
6952 ** next.  Applications that override the built-in mutex logic must be
6953 ** prepared to accommodate additional static mutexes.
6954 */
6955 enum SQLITE_MUTEX_FAST = 0;
6956 enum SQLITE_MUTEX_RECURSIVE = 1;
6957 enum SQLITE_MUTEX_STATIC_MASTER = 2;
6958 enum SQLITE_MUTEX_STATIC_MEM = 3; /* sqlite3_malloc() */
6959 enum SQLITE_MUTEX_STATIC_MEM2 = 4; /* NOT USED */
6960 enum SQLITE_MUTEX_STATIC_OPEN = 4; /* sqlite3BtreeOpen() */
6961 enum SQLITE_MUTEX_STATIC_PRNG = 5; /* sqlite3_randomness() */
6962 enum SQLITE_MUTEX_STATIC_LRU = 6; /* lru page list */
6963 enum SQLITE_MUTEX_STATIC_LRU2 = 7; /* NOT USED */
6964 enum SQLITE_MUTEX_STATIC_PMEM = 7; /* sqlite3PageMalloc() */
6965 enum SQLITE_MUTEX_STATIC_APP1 = 8; /* For use by application */
6966 enum SQLITE_MUTEX_STATIC_APP2 = 9; /* For use by application */
6967 enum SQLITE_MUTEX_STATIC_APP3 = 10; /* For use by application */
6968 enum SQLITE_MUTEX_STATIC_VFS1 = 11; /* For use by built-in VFS */
6969 enum SQLITE_MUTEX_STATIC_VFS2 = 12; /* For use by extension VFS */
6970 enum SQLITE_MUTEX_STATIC_VFS3 = 13; /* For use by application VFS */
6971 
6972 /*
6973 ** CAPI3REF: Retrieve the mutex for a database connection
6974 ** METHOD: sqlite3
6975 **
6976 ** ^This interface returns a pointer the [sqlite3_mutex] object that
6977 ** serializes access to the [database connection] given in the argument
6978 ** when the [threading mode] is Serialized.
6979 ** ^If the [threading mode] is Single-thread or Multi-thread then this
6980 ** routine returns a NULL pointer.
6981 */
6982 sqlite3_mutex* sqlite3_db_mutex(sqlite3*);
6983 
6984 /*
6985 ** CAPI3REF: Low-Level Control Of Database Files
6986 ** METHOD: sqlite3
6987 **
6988 ** ^The [sqlite3_file_control()] interface makes a direct call to the
6989 ** xFileControl method for the [sqlite3_io_methods] object associated
6990 ** with a particular database identified by the second argument. ^The
6991 ** name of the database is "main" for the main database or "temp" for the
6992 ** TEMP database, or the name that appears after the AS keyword for
6993 ** databases that are added using the [ATTACH] SQL command.
6994 ** ^A NULL pointer can be used in place of "main" to refer to the
6995 ** main database file.
6996 ** ^The third and fourth parameters to this routine
6997 ** are passed directly through to the second and third parameters of
6998 ** the xFileControl method.  ^The return value of the xFileControl
6999 ** method becomes the return value of this routine.
7000 **
7001 ** ^The SQLITE_FCNTL_FILE_POINTER value for the op parameter causes
7002 ** a pointer to the underlying [sqlite3_file] object to be written into
7003 ** the space pointed to by the 4th parameter.  ^The SQLITE_FCNTL_FILE_POINTER
7004 ** case is a short-circuit path which does not actually invoke the
7005 ** underlying sqlite3_io_methods.xFileControl method.
7006 **
7007 ** ^If the second parameter (zDbName) does not match the name of any
7008 ** open database file, then SQLITE_ERROR is returned.  ^This error
7009 ** code is not remembered and will not be recalled by [sqlite3_errcode()]
7010 ** or [sqlite3_errmsg()].  The underlying xFileControl method might
7011 ** also return SQLITE_ERROR.  There is no way to distinguish between
7012 ** an incorrect zDbName and an SQLITE_ERROR return from the underlying
7013 ** xFileControl method.
7014 **
7015 ** See also: [SQLITE_FCNTL_LOCKSTATE]
7016 */
7017 int sqlite3_file_control(sqlite3*, const(char)* zDbName, int op, void*);
7018 
7019 /*
7020 ** CAPI3REF: Testing Interface
7021 **
7022 ** ^The sqlite3_test_control() interface is used to read out internal
7023 ** state of SQLite and to inject faults into SQLite for testing
7024 ** purposes.  ^The first parameter is an operation code that determines
7025 ** the number, meaning, and operation of all subsequent parameters.
7026 **
7027 ** This interface is not for use by applications.  It exists solely
7028 ** for verifying the correct operation of the SQLite library.  Depending
7029 ** on how the SQLite library is compiled, this interface might not exist.
7030 **
7031 ** The details of the operation codes, their meanings, the parameters
7032 ** they take, and what they do are all subject to change without notice.
7033 ** Unlike most of the SQLite API, this function is not guaranteed to
7034 ** operate consistently from one release to the next.
7035 */
7036 int sqlite3_test_control(int op, ...);
7037 
7038 /*
7039 ** CAPI3REF: Testing Interface Operation Codes
7040 **
7041 ** These constants are the valid operation code parameters used
7042 ** as the first argument to [sqlite3_test_control()].
7043 **
7044 ** These parameters and their meanings are subject to change
7045 ** without notice.  These values are for testing purposes only.
7046 ** Applications should not use any of these parameters or the
7047 ** [sqlite3_test_control()] interface.
7048 */
7049 enum SQLITE_TESTCTRL_FIRST = 5;
7050 enum SQLITE_TESTCTRL_PRNG_SAVE = 5;
7051 enum SQLITE_TESTCTRL_PRNG_RESTORE = 6;
7052 enum SQLITE_TESTCTRL_PRNG_RESET = 7;
7053 enum SQLITE_TESTCTRL_BITVEC_TEST = 8;
7054 enum SQLITE_TESTCTRL_FAULT_INSTALL = 9;
7055 enum SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS = 10;
7056 enum SQLITE_TESTCTRL_PENDING_BYTE = 11;
7057 enum SQLITE_TESTCTRL_ASSERT = 12;
7058 enum SQLITE_TESTCTRL_ALWAYS = 13;
7059 enum SQLITE_TESTCTRL_RESERVE = 14;
7060 enum SQLITE_TESTCTRL_OPTIMIZATIONS = 15;
7061 enum SQLITE_TESTCTRL_ISKEYWORD = 16;
7062 enum SQLITE_TESTCTRL_SCRATCHMALLOC = 17; /* NOT USED */
7063 enum SQLITE_TESTCTRL_LOCALTIME_FAULT = 18;
7064 enum SQLITE_TESTCTRL_EXPLAIN_STMT = 19; /* NOT USED */
7065 enum SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD = 19;
7066 enum SQLITE_TESTCTRL_NEVER_CORRUPT = 20;
7067 enum SQLITE_TESTCTRL_VDBE_COVERAGE = 21;
7068 enum SQLITE_TESTCTRL_BYTEORDER = 22;
7069 enum SQLITE_TESTCTRL_ISINIT = 23;
7070 enum SQLITE_TESTCTRL_SORTER_MMAP = 24;
7071 enum SQLITE_TESTCTRL_IMPOSTER = 25;
7072 enum SQLITE_TESTCTRL_LAST = 25;
7073 
7074 /*
7075 ** CAPI3REF: SQLite Runtime Status
7076 **
7077 ** ^These interfaces are used to retrieve runtime status information
7078 ** about the performance of SQLite, and optionally to reset various
7079 ** highwater marks.  ^The first argument is an integer code for
7080 ** the specific parameter to measure.  ^(Recognized integer codes
7081 ** are of the form [status parameters | SQLITE_STATUS_...].)^
7082 ** ^The current value of the parameter is returned into *pCurrent.
7083 ** ^The highest recorded value is returned in *pHighwater.  ^If the
7084 ** resetFlag is true, then the highest record value is reset after
7085 ** *pHighwater is written.  ^(Some parameters do not record the highest
7086 ** value.  For those parameters
7087 ** nothing is written into *pHighwater and the resetFlag is ignored.)^
7088 ** ^(Other parameters record only the highwater mark and not the current
7089 ** value.  For these latter parameters nothing is written into *pCurrent.)^
7090 **
7091 ** ^The sqlite3_status() and sqlite3_status64() routines return
7092 ** SQLITE_OK on success and a non-zero [error code] on failure.
7093 **
7094 ** If either the current value or the highwater mark is too large to
7095 ** be represented by a 32-bit integer, then the values returned by
7096 ** sqlite3_status() are undefined.
7097 **
7098 ** See also: [sqlite3_db_status()]
7099 */
7100 int sqlite3_status(int op, int* pCurrent, int* pHighwater, int resetFlag);
7101 int sqlite3_status64(
7102     int op,
7103     sqlite3_int64* pCurrent,
7104     sqlite3_int64* pHighwater,
7105     int resetFlag);
7106 
7107 /*
7108 ** CAPI3REF: Status Parameters
7109 ** KEYWORDS: {status parameters}
7110 **
7111 ** These integer constants designate various run-time status parameters
7112 ** that can be returned by [sqlite3_status()].
7113 **
7114 ** <dl>
7115 ** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
7116 ** <dd>This parameter is the current amount of memory checked out
7117 ** using [sqlite3_malloc()], either directly or indirectly.  The
7118 ** figure includes calls made to [sqlite3_malloc()] by the application
7119 ** and internal memory usage by the SQLite library.  Auxiliary page-cache
7120 ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
7121 ** this parameter.  The amount returned is the sum of the allocation
7122 ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
7123 **
7124 ** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
7125 ** <dd>This parameter records the largest memory allocation request
7126 ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
7127 ** internal equivalents).  Only the value returned in the
7128 ** *pHighwater parameter to [sqlite3_status()] is of interest.
7129 ** The value written into the *pCurrent parameter is undefined.</dd>)^
7130 **
7131 ** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
7132 ** <dd>This parameter records the number of separate memory allocations
7133 ** currently checked out.</dd>)^
7134 **
7135 ** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
7136 ** <dd>This parameter returns the number of pages used out of the
7137 ** [pagecache memory allocator] that was configured using
7138 ** [SQLITE_CONFIG_PAGECACHE].  The
7139 ** value returned is in pages, not in bytes.</dd>)^
7140 **
7141 ** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]]
7142 ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
7143 ** <dd>This parameter returns the number of bytes of page cache
7144 ** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
7145 ** buffer and where forced to overflow to [sqlite3_malloc()].  The
7146 ** returned value includes allocations that overflowed because they
7147 ** where too large (they were larger than the "sz" parameter to
7148 ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
7149 ** no space was left in the page cache.</dd>)^
7150 **
7151 ** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
7152 ** <dd>This parameter records the largest memory allocation request
7153 ** handed to [pagecache memory allocator].  Only the value returned in the
7154 ** *pHighwater parameter to [sqlite3_status()] is of interest.
7155 ** The value written into the *pCurrent parameter is undefined.</dd>)^
7156 **
7157 ** [[SQLITE_STATUS_SCRATCH_USED]] <dt>SQLITE_STATUS_SCRATCH_USED</dt>
7158 ** <dd>No longer used.</dd>
7159 **
7160 ** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
7161 ** <dd>No longer used.</dd>
7162 **
7163 ** [[SQLITE_STATUS_SCRATCH_SIZE]] <dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
7164 ** <dd>No longer used.</dd>
7165 **
7166 ** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
7167 ** <dd>The *pHighwater parameter records the deepest parser stack.
7168 ** The *pCurrent value is undefined.  The *pHighwater value is only
7169 ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
7170 ** </dl>
7171 **
7172 ** New status parameters may be added from time to time.
7173 */
7174 enum SQLITE_STATUS_MEMORY_USED = 0;
7175 enum SQLITE_STATUS_PAGECACHE_USED = 1;
7176 enum SQLITE_STATUS_PAGECACHE_OVERFLOW = 2;
7177 enum SQLITE_STATUS_SCRATCH_USED = 3; /* NOT USED */
7178 enum SQLITE_STATUS_SCRATCH_OVERFLOW = 4; /* NOT USED */
7179 enum SQLITE_STATUS_MALLOC_SIZE = 5;
7180 enum SQLITE_STATUS_PARSER_STACK = 6;
7181 enum SQLITE_STATUS_PAGECACHE_SIZE = 7;
7182 enum SQLITE_STATUS_SCRATCH_SIZE = 8; /* NOT USED */
7183 enum SQLITE_STATUS_MALLOC_COUNT = 9;
7184 
7185 /*
7186 ** CAPI3REF: Database Connection Status
7187 ** METHOD: sqlite3
7188 **
7189 ** ^This interface is used to retrieve runtime status information
7190 ** about a single [database connection].  ^The first argument is the
7191 ** database connection object to be interrogated.  ^The second argument
7192 ** is an integer constant, taken from the set of
7193 ** [SQLITE_DBSTATUS options], that
7194 ** determines the parameter to interrogate.  The set of
7195 ** [SQLITE_DBSTATUS options] is likely
7196 ** to grow in future releases of SQLite.
7197 **
7198 ** ^The current value of the requested parameter is written into *pCur
7199 ** and the highest instantaneous value is written into *pHiwtr.  ^If
7200 ** the resetFlg is true, then the highest instantaneous value is
7201 ** reset back down to the current value.
7202 **
7203 ** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
7204 ** non-zero [error code] on failure.
7205 **
7206 ** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
7207 */
7208 int sqlite3_db_status(sqlite3*, int op, int* pCur, int* pHiwtr, int resetFlg);
7209 
7210 /*
7211 ** CAPI3REF: Status Parameters for database connections
7212 ** KEYWORDS: {SQLITE_DBSTATUS options}
7213 **
7214 ** These constants are the available integer "verbs" that can be passed as
7215 ** the second argument to the [sqlite3_db_status()] interface.
7216 **
7217 ** New verbs may be added in future releases of SQLite. Existing verbs
7218 ** might be discontinued. Applications should check the return code from
7219 ** [sqlite3_db_status()] to make sure that the call worked.
7220 ** The [sqlite3_db_status()] interface will return a non-zero error code
7221 ** if a discontinued or unsupported verb is invoked.
7222 **
7223 ** <dl>
7224 ** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
7225 ** <dd>This parameter returns the number of lookaside memory slots currently
7226 ** checked out.</dd>)^
7227 **
7228 ** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>
7229 ** <dd>This parameter returns the number malloc attempts that were
7230 ** satisfied using lookaside memory. Only the high-water value is meaningful;
7231 ** the current value is always zero.)^
7232 **
7233 ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
7234 ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>
7235 ** <dd>This parameter returns the number malloc attempts that might have
7236 ** been satisfied using lookaside memory but failed due to the amount of
7237 ** memory requested being larger than the lookaside slot size.
7238 ** Only the high-water value is meaningful;
7239 ** the current value is always zero.)^
7240 **
7241 ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
7242 ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>
7243 ** <dd>This parameter returns the number malloc attempts that might have
7244 ** been satisfied using lookaside memory but failed due to all lookaside
7245 ** memory already being in use.
7246 ** Only the high-water value is meaningful;
7247 ** the current value is always zero.)^
7248 **
7249 ** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
7250 ** <dd>This parameter returns the approximate number of bytes of heap
7251 ** memory used by all pager caches associated with the database connection.)^
7252 ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
7253 **
7254 ** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]]
7255 ** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt>
7256 ** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a
7257 ** pager cache is shared between two or more connections the bytes of heap
7258 ** memory used by that pager cache is divided evenly between the attached
7259 ** connections.)^  In other words, if none of the pager caches associated
7260 ** with the database connection are shared, this request returns the same
7261 ** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are
7262 ** shared, the value returned by this call will be smaller than that returned
7263 ** by DBSTATUS_CACHE_USED. ^The highwater mark associated with
7264 ** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0.
7265 **
7266 ** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
7267 ** <dd>This parameter returns the approximate number of bytes of heap
7268 ** memory used to store the schema for all databases associated
7269 ** with the connection - main, temp, and any [ATTACH]-ed databases.)^
7270 ** ^The full amount of memory used by the schemas is reported, even if the
7271 ** schema memory is shared with other database connections due to
7272 ** [shared cache mode] being enabled.
7273 ** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
7274 **
7275 ** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
7276 ** <dd>This parameter returns the approximate number of bytes of heap
7277 ** and lookaside memory used by all prepared statements associated with
7278 ** the database connection.)^
7279 ** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
7280 ** </dd>
7281 **
7282 ** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>
7283 ** <dd>This parameter returns the number of pager cache hits that have
7284 ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT
7285 ** is always 0.
7286 ** </dd>
7287 **
7288 ** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt>
7289 ** <dd>This parameter returns the number of pager cache misses that have
7290 ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS
7291 ** is always 0.
7292 ** </dd>
7293 **
7294 ** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt>
7295 ** <dd>This parameter returns the number of dirty cache entries that have
7296 ** been written to disk. Specifically, the number of pages written to the
7297 ** wal file in wal mode databases, or the number of pages written to the
7298 ** database file in rollback mode databases. Any pages written as part of
7299 ** transaction rollback or database recovery operations are not included.
7300 ** If an IO or other error occurs while writing a page to disk, the effect
7301 ** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
7302 ** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
7303 ** </dd>
7304 **
7305 ** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>
7306 ** <dd>This parameter returns zero for the current value if and only if
7307 ** all foreign key constraints (deferred or immediate) have been
7308 ** resolved.)^  ^The highwater mark is always 0.
7309 ** </dd>
7310 ** </dl>
7311 */
7312 enum SQLITE_DBSTATUS_LOOKASIDE_USED = 0;
7313 enum SQLITE_DBSTATUS_CACHE_USED = 1;
7314 enum SQLITE_DBSTATUS_SCHEMA_USED = 2;
7315 enum SQLITE_DBSTATUS_STMT_USED = 3;
7316 enum SQLITE_DBSTATUS_LOOKASIDE_HIT = 4;
7317 enum SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE = 5;
7318 enum SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL = 6;
7319 enum SQLITE_DBSTATUS_CACHE_HIT = 7;
7320 enum SQLITE_DBSTATUS_CACHE_MISS = 8;
7321 enum SQLITE_DBSTATUS_CACHE_WRITE = 9;
7322 enum SQLITE_DBSTATUS_DEFERRED_FKS = 10;
7323 enum SQLITE_DBSTATUS_CACHE_USED_SHARED = 11;
7324 enum SQLITE_DBSTATUS_MAX = 11; /* Largest defined DBSTATUS */
7325 
7326 /*
7327 ** CAPI3REF: Prepared Statement Status
7328 ** METHOD: sqlite3_stmt
7329 **
7330 ** ^(Each prepared statement maintains various
7331 ** [SQLITE_STMTSTATUS counters] that measure the number
7332 ** of times it has performed specific operations.)^  These counters can
7333 ** be used to monitor the performance characteristics of the prepared
7334 ** statements.  For example, if the number of table steps greatly exceeds
7335 ** the number of table searches or result rows, that would tend to indicate
7336 ** that the prepared statement is using a full table scan rather than
7337 ** an index.
7338 **
7339 ** ^(This interface is used to retrieve and reset counter values from
7340 ** a [prepared statement].  The first argument is the prepared statement
7341 ** object to be interrogated.  The second argument
7342 ** is an integer code for a specific [SQLITE_STMTSTATUS counter]
7343 ** to be interrogated.)^
7344 ** ^The current value of the requested counter is returned.
7345 ** ^If the resetFlg is true, then the counter is reset to zero after this
7346 ** interface call returns.
7347 **
7348 ** See also: [sqlite3_status()] and [sqlite3_db_status()].
7349 */
7350 int sqlite3_stmt_status(sqlite3_stmt*, int op, int resetFlg);
7351 
7352 /*
7353 ** CAPI3REF: Status Parameters for prepared statements
7354 ** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
7355 **
7356 ** These preprocessor macros define integer codes that name counter
7357 ** values associated with the [sqlite3_stmt_status()] interface.
7358 ** The meanings of the various counters are as follows:
7359 **
7360 ** <dl>
7361 ** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
7362 ** <dd>^This is the number of times that SQLite has stepped forward in
7363 ** a table as part of a full table scan.  Large numbers for this counter
7364 ** may indicate opportunities for performance improvement through
7365 ** careful use of indices.</dd>
7366 **
7367 ** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>
7368 ** <dd>^This is the number of sort operations that have occurred.
7369 ** A non-zero value in this counter may indicate an opportunity to
7370 ** improvement performance through careful use of indices.</dd>
7371 **
7372 ** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
7373 ** <dd>^This is the number of rows inserted into transient indices that
7374 ** were created automatically in order to help joins run faster.
7375 ** A non-zero value in this counter may indicate an opportunity to
7376 ** improvement performance by adding permanent indices that do not
7377 ** need to be reinitialized each time the statement is run.</dd>
7378 **
7379 ** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>
7380 ** <dd>^This is the number of virtual machine operations executed
7381 ** by the prepared statement if that number is less than or equal
7382 ** to 2147483647.  The number of virtual machine operations can be
7383 ** used as a proxy for the total work done by the prepared statement.
7384 ** If the number of virtual machine operations exceeds 2147483647
7385 ** then the value returned by this statement status code is undefined.
7386 **
7387 ** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt>
7388 ** <dd>^This is the number of times that the prepare statement has been
7389 ** automatically regenerated due to schema changes or change to
7390 ** [bound parameters] that might affect the query plan.
7391 **
7392 ** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt>
7393 ** <dd>^This is the number of times that the prepared statement has
7394 ** been run.  A single "run" for the purposes of this counter is one
7395 ** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()].
7396 ** The counter is incremented on the first [sqlite3_step()] call of each
7397 ** cycle.
7398 **
7399 ** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt>
7400 ** <dd>^This is the approximate number of bytes of heap memory
7401 ** used to store the prepared statement.  ^This value is not actually
7402 ** a counter, and so the resetFlg parameter to sqlite3_stmt_status()
7403 ** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED.
7404 ** </dd>
7405 ** </dl>
7406 */
7407 enum SQLITE_STMTSTATUS_FULLSCAN_STEP = 1;
7408 enum SQLITE_STMTSTATUS_SORT = 2;
7409 enum SQLITE_STMTSTATUS_AUTOINDEX = 3;
7410 enum SQLITE_STMTSTATUS_VM_STEP = 4;
7411 enum SQLITE_STMTSTATUS_REPREPARE = 5;
7412 enum SQLITE_STMTSTATUS_RUN = 6;
7413 enum SQLITE_STMTSTATUS_MEMUSED = 99;
7414 
7415 /*
7416 ** CAPI3REF: Custom Page Cache Object
7417 **
7418 ** The sqlite3_pcache type is opaque.  It is implemented by
7419 ** the pluggable module.  The SQLite core has no knowledge of
7420 ** its size or internal structure and never deals with the
7421 ** sqlite3_pcache object except by holding and passing pointers
7422 ** to the object.
7423 **
7424 ** See [sqlite3_pcache_methods2] for additional information.
7425 */
7426 struct sqlite3_pcache;
7427 
7428 /*
7429 ** CAPI3REF: Custom Page Cache Object
7430 **
7431 ** The sqlite3_pcache_page object represents a single page in the
7432 ** page cache.  The page cache will allocate instances of this
7433 ** object.  Various methods of the page cache use pointers to instances
7434 ** of this object as parameters or as their return value.
7435 **
7436 ** See [sqlite3_pcache_methods2] for additional information.
7437 */
7438 struct sqlite3_pcache_page
7439 {
7440     void* pBuf; /* The content of the page */
7441     void* pExtra; /* Extra information associated with the page */
7442 }
7443 
7444 /*
7445 ** CAPI3REF: Application Defined Page Cache.
7446 ** KEYWORDS: {page cache}
7447 **
7448 ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
7449 ** register an alternative page cache implementation by passing in an
7450 ** instance of the sqlite3_pcache_methods2 structure.)^
7451 ** In many applications, most of the heap memory allocated by
7452 ** SQLite is used for the page cache.
7453 ** By implementing a
7454 ** custom page cache using this API, an application can better control
7455 ** the amount of memory consumed by SQLite, the way in which
7456 ** that memory is allocated and released, and the policies used to
7457 ** determine exactly which parts of a database file are cached and for
7458 ** how long.
7459 **
7460 ** The alternative page cache mechanism is an
7461 ** extreme measure that is only needed by the most demanding applications.
7462 ** The built-in page cache is recommended for most uses.
7463 **
7464 ** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
7465 ** internal buffer by SQLite within the call to [sqlite3_config].  Hence
7466 ** the application may discard the parameter after the call to
7467 ** [sqlite3_config()] returns.)^
7468 **
7469 ** [[the xInit() page cache method]]
7470 ** ^(The xInit() method is called once for each effective
7471 ** call to [sqlite3_initialize()])^
7472 ** (usually only once during the lifetime of the process). ^(The xInit()
7473 ** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
7474 ** The intent of the xInit() method is to set up global data structures
7475 ** required by the custom page cache implementation.
7476 ** ^(If the xInit() method is NULL, then the
7477 ** built-in default page cache is used instead of the application defined
7478 ** page cache.)^
7479 **
7480 ** [[the xShutdown() page cache method]]
7481 ** ^The xShutdown() method is called by [sqlite3_shutdown()].
7482 ** It can be used to clean up
7483 ** any outstanding resources before process shutdown, if required.
7484 ** ^The xShutdown() method may be NULL.
7485 **
7486 ** ^SQLite automatically serializes calls to the xInit method,
7487 ** so the xInit method need not be threadsafe.  ^The
7488 ** xShutdown method is only called from [sqlite3_shutdown()] so it does
7489 ** not need to be threadsafe either.  All other methods must be threadsafe
7490 ** in multithreaded applications.
7491 **
7492 ** ^SQLite will never invoke xInit() more than once without an intervening
7493 ** call to xShutdown().
7494 **
7495 ** [[the xCreate() page cache methods]]
7496 ** ^SQLite invokes the xCreate() method to construct a new cache instance.
7497 ** SQLite will typically create one cache instance for each open database file,
7498 ** though this is not guaranteed. ^The
7499 ** first parameter, szPage, is the size in bytes of the pages that must
7500 ** be allocated by the cache.  ^szPage will always a power of two.  ^The
7501 ** second parameter szExtra is a number of bytes of extra storage
7502 ** associated with each page cache entry.  ^The szExtra parameter will
7503 ** a number less than 250.  SQLite will use the
7504 ** extra szExtra bytes on each page to store metadata about the underlying
7505 ** database page on disk.  The value passed into szExtra depends
7506 ** on the SQLite version, the target platform, and how SQLite was compiled.
7507 ** ^The third argument to xCreate(), bPurgeable, is true if the cache being
7508 ** created will be used to cache database pages of a file stored on disk, or
7509 ** false if it is used for an in-memory database. The cache implementation
7510 ** does not have to do anything special based with the value of bPurgeable;
7511 ** it is purely advisory.  ^On a cache where bPurgeable is false, SQLite will
7512 ** never invoke xUnpin() except to deliberately delete a page.
7513 ** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
7514 ** false will always have the "discard" flag set to true.
7515 ** ^Hence, a cache created with bPurgeable false will
7516 ** never contain any unpinned pages.
7517 **
7518 ** [[the xCachesize() page cache method]]
7519 ** ^(The xCachesize() method may be called at any time by SQLite to set the
7520 ** suggested maximum cache-size (number of pages stored by) the cache
7521 ** instance passed as the first argument. This is the value configured using
7522 ** the SQLite "[PRAGMA cache_size]" command.)^  As with the bPurgeable
7523 ** parameter, the implementation is not required to do anything with this
7524 ** value; it is advisory only.
7525 **
7526 ** [[the xPagecount() page cache methods]]
7527 ** The xPagecount() method must return the number of pages currently
7528 ** stored in the cache, both pinned and unpinned.
7529 **
7530 ** [[the xFetch() page cache methods]]
7531 ** The xFetch() method locates a page in the cache and returns a pointer to
7532 ** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
7533 ** The pBuf element of the returned sqlite3_pcache_page object will be a
7534 ** pointer to a buffer of szPage bytes used to store the content of a
7535 ** single database page.  The pExtra element of sqlite3_pcache_page will be
7536 ** a pointer to the szExtra bytes of extra storage that SQLite has requested
7537 ** for each entry in the page cache.
7538 **
7539 ** The page to be fetched is determined by the key. ^The minimum key value
7540 ** is 1.  After it has been retrieved using xFetch, the page is considered
7541 ** to be "pinned".
7542 **
7543 ** If the requested page is already in the page cache, then the page cache
7544 ** implementation must return a pointer to the page buffer with its content
7545 ** intact.  If the requested page is not already in the cache, then the
7546 ** cache implementation should use the value of the createFlag
7547 ** parameter to help it determined what action to take:
7548 **
7549 ** <table border=1 width=85% align=center>
7550 ** <tr><th> createFlag <th> Behavior when page is not already in cache
7551 ** <tr><td> 0 <td> Do not allocate a new page.  Return NULL.
7552 ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
7553 **                 Otherwise return NULL.
7554 ** <tr><td> 2 <td> Make every effort to allocate a new page.  Only return
7555 **                 NULL if allocating a new page is effectively impossible.
7556 ** </table>
7557 **
7558 ** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  SQLite
7559 ** will only use a createFlag of 2 after a prior call with a createFlag of 1
7560 ** failed.)^  In between the to xFetch() calls, SQLite may
7561 ** attempt to unpin one or more cache pages by spilling the content of
7562 ** pinned pages to disk and synching the operating system disk cache.
7563 **
7564 ** [[the xUnpin() page cache method]]
7565 ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
7566 ** as its second argument.  If the third parameter, discard, is non-zero,
7567 ** then the page must be evicted from the cache.
7568 ** ^If the discard parameter is
7569 ** zero, then the page may be discarded or retained at the discretion of
7570 ** page cache implementation. ^The page cache implementation
7571 ** may choose to evict unpinned pages at any time.
7572 **
7573 ** The cache must not perform any reference counting. A single
7574 ** call to xUnpin() unpins the page regardless of the number of prior calls
7575 ** to xFetch().
7576 **
7577 ** [[the xRekey() page cache methods]]
7578 ** The xRekey() method is used to change the key value associated with the
7579 ** page passed as the second argument. If the cache
7580 ** previously contains an entry associated with newKey, it must be
7581 ** discarded. ^Any prior cache entry associated with newKey is guaranteed not
7582 ** to be pinned.
7583 **
7584 ** When SQLite calls the xTruncate() method, the cache must discard all
7585 ** existing cache entries with page numbers (keys) greater than or equal
7586 ** to the value of the iLimit parameter passed to xTruncate(). If any
7587 ** of these pages are pinned, they are implicitly unpinned, meaning that
7588 ** they can be safely discarded.
7589 **
7590 ** [[the xDestroy() page cache method]]
7591 ** ^The xDestroy() method is used to delete a cache allocated by xCreate().
7592 ** All resources associated with the specified cache should be freed. ^After
7593 ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
7594 ** handle invalid, and will not use it with any other sqlite3_pcache_methods2
7595 ** functions.
7596 **
7597 ** [[the xShrink() page cache method]]
7598 ** ^SQLite invokes the xShrink() method when it wants the page cache to
7599 ** free up as much of heap memory as possible.  The page cache implementation
7600 ** is not obligated to free any memory, but well-behaved implementations should
7601 ** do their best.
7602 */
7603 struct sqlite3_pcache_methods2
7604 {
7605     int iVersion;
7606     void* pArg;
7607     int function(void*) xInit;
7608     void function(void*) xShutdown;
7609     sqlite3_pcache* function(int szPage, int szExtra, int bPurgeable) xCreate;
7610     void function(sqlite3_pcache*, int nCachesize) xCachesize;
7611     int function(sqlite3_pcache*) xPagecount;
7612     sqlite3_pcache_page* function(sqlite3_pcache*, uint key, int createFlag) xFetch;
7613     void function(sqlite3_pcache*, sqlite3_pcache_page*, int discard) xUnpin;
7614     void function(sqlite3_pcache*, sqlite3_pcache_page*, uint oldKey, uint newKey) xRekey;
7615     void function(sqlite3_pcache*, uint iLimit) xTruncate;
7616     void function(sqlite3_pcache*) xDestroy;
7617     void function(sqlite3_pcache*) xShrink;
7618 }
7619 
7620 /*
7621 ** This is the obsolete pcache_methods object that has now been replaced
7622 ** by sqlite3_pcache_methods2.  This object is not used by SQLite.  It is
7623 ** retained in the header file for backwards compatibility only.
7624 */
7625 struct sqlite3_pcache_methods
7626 {
7627     void* pArg;
7628     int function(void*) xInit;
7629     void function(void*) xShutdown;
7630     sqlite3_pcache* function(int szPage, int bPurgeable) xCreate;
7631     void function(sqlite3_pcache*, int nCachesize) xCachesize;
7632     int function(sqlite3_pcache*) xPagecount;
7633     void* function(sqlite3_pcache*, uint key, int createFlag) xFetch;
7634     void function(sqlite3_pcache*, void*, int discard) xUnpin;
7635     void function(sqlite3_pcache*, void*, uint oldKey, uint newKey) xRekey;
7636     void function(sqlite3_pcache*, uint iLimit) xTruncate;
7637     void function(sqlite3_pcache*) xDestroy;
7638 }
7639 
7640 /*
7641 ** CAPI3REF: Online Backup Object
7642 **
7643 ** The sqlite3_backup object records state information about an ongoing
7644 ** online backup operation.  ^The sqlite3_backup object is created by
7645 ** a call to [sqlite3_backup_init()] and is destroyed by a call to
7646 ** [sqlite3_backup_finish()].
7647 **
7648 ** See Also: [Using the SQLite Online Backup API]
7649 */
7650 struct sqlite3_backup;
7651 
7652 /*
7653 ** CAPI3REF: Online Backup API.
7654 **
7655 ** The backup API copies the content of one database into another.
7656 ** It is useful either for creating backups of databases or
7657 ** for copying in-memory databases to or from persistent files.
7658 **
7659 ** See Also: [Using the SQLite Online Backup API]
7660 **
7661 ** ^SQLite holds a write transaction open on the destination database file
7662 ** for the duration of the backup operation.
7663 ** ^The source database is read-locked only while it is being read;
7664 ** it is not locked continuously for the entire backup operation.
7665 ** ^Thus, the backup may be performed on a live source database without
7666 ** preventing other database connections from
7667 ** reading or writing to the source database while the backup is underway.
7668 **
7669 ** ^(To perform a backup operation:
7670 **   <ol>
7671 **     <li><b>sqlite3_backup_init()</b> is called once to initialize the
7672 **         backup,
7673 **     <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
7674 **         the data between the two databases, and finally
7675 **     <li><b>sqlite3_backup_finish()</b> is called to release all resources
7676 **         associated with the backup operation.
7677 **   </ol>)^
7678 ** There should be exactly one call to sqlite3_backup_finish() for each
7679 ** successful call to sqlite3_backup_init().
7680 **
7681 ** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>
7682 **
7683 ** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
7684 ** [database connection] associated with the destination database
7685 ** and the database name, respectively.
7686 ** ^The database name is "main" for the main database, "temp" for the
7687 ** temporary database, or the name specified after the AS keyword in
7688 ** an [ATTACH] statement for an attached database.
7689 ** ^The S and M arguments passed to
7690 ** sqlite3_backup_init(D,N,S,M) identify the [database connection]
7691 ** and database name of the source database, respectively.
7692 ** ^The source and destination [database connections] (parameters S and D)
7693 ** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
7694 ** an error.
7695 **
7696 ** ^A call to sqlite3_backup_init() will fail, returning NULL, if
7697 ** there is already a read or read-write transaction open on the
7698 ** destination database.
7699 **
7700 ** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
7701 ** returned and an error code and error message are stored in the
7702 ** destination [database connection] D.
7703 ** ^The error code and message for the failed call to sqlite3_backup_init()
7704 ** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
7705 ** [sqlite3_errmsg16()] functions.
7706 ** ^A successful call to sqlite3_backup_init() returns a pointer to an
7707 ** [sqlite3_backup] object.
7708 ** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
7709 ** sqlite3_backup_finish() functions to perform the specified backup
7710 ** operation.
7711 **
7712 ** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>
7713 **
7714 ** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
7715 ** the source and destination databases specified by [sqlite3_backup] object B.
7716 ** ^If N is negative, all remaining source pages are copied.
7717 ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
7718 ** are still more pages to be copied, then the function returns [SQLITE_OK].
7719 ** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
7720 ** from source to destination, then it returns [SQLITE_DONE].
7721 ** ^If an error occurs while running sqlite3_backup_step(B,N),
7722 ** then an [error code] is returned. ^As well as [SQLITE_OK] and
7723 ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
7724 ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
7725 ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
7726 **
7727 ** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
7728 ** <ol>
7729 ** <li> the destination database was opened read-only, or
7730 ** <li> the destination database is using write-ahead-log journaling
7731 ** and the destination and source page sizes differ, or
7732 ** <li> the destination database is an in-memory database and the
7733 ** destination and source page sizes differ.
7734 ** </ol>)^
7735 **
7736 ** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
7737 ** the [sqlite3_busy_handler | busy-handler function]
7738 ** is invoked (if one is specified). ^If the
7739 ** busy-handler returns non-zero before the lock is available, then
7740 ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
7741 ** sqlite3_backup_step() can be retried later. ^If the source
7742 ** [database connection]
7743 ** is being used to write to the source database when sqlite3_backup_step()
7744 ** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
7745 ** case the call to sqlite3_backup_step() can be retried later on. ^(If
7746 ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
7747 ** [SQLITE_READONLY] is returned, then
7748 ** there is no point in retrying the call to sqlite3_backup_step(). These
7749 ** errors are considered fatal.)^  The application must accept
7750 ** that the backup operation has failed and pass the backup operation handle
7751 ** to the sqlite3_backup_finish() to release associated resources.
7752 **
7753 ** ^The first call to sqlite3_backup_step() obtains an exclusive lock
7754 ** on the destination file. ^The exclusive lock is not released until either
7755 ** sqlite3_backup_finish() is called or the backup operation is complete
7756 ** and sqlite3_backup_step() returns [SQLITE_DONE].  ^Every call to
7757 ** sqlite3_backup_step() obtains a [shared lock] on the source database that
7758 ** lasts for the duration of the sqlite3_backup_step() call.
7759 ** ^Because the source database is not locked between calls to
7760 ** sqlite3_backup_step(), the source database may be modified mid-way
7761 ** through the backup process.  ^If the source database is modified by an
7762 ** external process or via a database connection other than the one being
7763 ** used by the backup operation, then the backup will be automatically
7764 ** restarted by the next call to sqlite3_backup_step(). ^If the source
7765 ** database is modified by the using the same database connection as is used
7766 ** by the backup operation, then the backup database is automatically
7767 ** updated at the same time.
7768 **
7769 ** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>
7770 **
7771 ** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
7772 ** application wishes to abandon the backup operation, the application
7773 ** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
7774 ** ^The sqlite3_backup_finish() interfaces releases all
7775 ** resources associated with the [sqlite3_backup] object.
7776 ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
7777 ** active write-transaction on the destination database is rolled back.
7778 ** The [sqlite3_backup] object is invalid
7779 ** and may not be used following a call to sqlite3_backup_finish().
7780 **
7781 ** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
7782 ** sqlite3_backup_step() errors occurred, regardless or whether or not
7783 ** sqlite3_backup_step() completed.
7784 ** ^If an out-of-memory condition or IO error occurred during any prior
7785 ** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
7786 ** sqlite3_backup_finish() returns the corresponding [error code].
7787 **
7788 ** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
7789 ** is not a permanent error and does not affect the return value of
7790 ** sqlite3_backup_finish().
7791 **
7792 ** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]]
7793 ** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
7794 **
7795 ** ^The sqlite3_backup_remaining() routine returns the number of pages still
7796 ** to be backed up at the conclusion of the most recent sqlite3_backup_step().
7797 ** ^The sqlite3_backup_pagecount() routine returns the total number of pages
7798 ** in the source database at the conclusion of the most recent
7799 ** sqlite3_backup_step().
7800 ** ^(The values returned by these functions are only updated by
7801 ** sqlite3_backup_step(). If the source database is modified in a way that
7802 ** changes the size of the source database or the number of pages remaining,
7803 ** those changes are not reflected in the output of sqlite3_backup_pagecount()
7804 ** and sqlite3_backup_remaining() until after the next
7805 ** sqlite3_backup_step().)^
7806 **
7807 ** <b>Concurrent Usage of Database Handles</b>
7808 **
7809 ** ^The source [database connection] may be used by the application for other
7810 ** purposes while a backup operation is underway or being initialized.
7811 ** ^If SQLite is compiled and configured to support threadsafe database
7812 ** connections, then the source database connection may be used concurrently
7813 ** from within other threads.
7814 **
7815 ** However, the application must guarantee that the destination
7816 ** [database connection] is not passed to any other API (by any thread) after
7817 ** sqlite3_backup_init() is called and before the corresponding call to
7818 ** sqlite3_backup_finish().  SQLite does not currently check to see
7819 ** if the application incorrectly accesses the destination [database connection]
7820 ** and so no error code is reported, but the operations may malfunction
7821 ** nevertheless.  Use of the destination database connection while a
7822 ** backup is in progress might also also cause a mutex deadlock.
7823 **
7824 ** If running in [shared cache mode], the application must
7825 ** guarantee that the shared cache used by the destination database
7826 ** is not accessed while the backup is running. In practice this means
7827 ** that the application must guarantee that the disk file being
7828 ** backed up to is not accessed by any connection within the process,
7829 ** not just the specific connection that was passed to sqlite3_backup_init().
7830 **
7831 ** The [sqlite3_backup] object itself is partially threadsafe. Multiple
7832 ** threads may safely make multiple concurrent calls to sqlite3_backup_step().
7833 ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
7834 ** APIs are not strictly speaking threadsafe. If they are invoked at the
7835 ** same time as another thread is invoking sqlite3_backup_step() it is
7836 ** possible that they return invalid values.
7837 */
7838 /* Destination database handle */
7839 /* Destination database name */
7840 /* Source database handle */
7841 /* Source database name */
7842 sqlite3_backup* sqlite3_backup_init(
7843     sqlite3* pDest,
7844     const(char)* zDestName,
7845     sqlite3* pSource,
7846     const(char)* zSourceName);
7847 int sqlite3_backup_step(sqlite3_backup* p, int nPage);
7848 int sqlite3_backup_finish(sqlite3_backup* p);
7849 int sqlite3_backup_remaining(sqlite3_backup* p);
7850 int sqlite3_backup_pagecount(sqlite3_backup* p);
7851 
7852 /*
7853 ** CAPI3REF: Unlock Notification
7854 ** METHOD: sqlite3
7855 **
7856 ** ^When running in shared-cache mode, a database operation may fail with
7857 ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
7858 ** individual tables within the shared-cache cannot be obtained. See
7859 ** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
7860 ** ^This API may be used to register a callback that SQLite will invoke
7861 ** when the connection currently holding the required lock relinquishes it.
7862 ** ^This API is only available if the library was compiled with the
7863 ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
7864 **
7865 ** See Also: [Using the SQLite Unlock Notification Feature].
7866 **
7867 ** ^Shared-cache locks are released when a database connection concludes
7868 ** its current transaction, either by committing it or rolling it back.
7869 **
7870 ** ^When a connection (known as the blocked connection) fails to obtain a
7871 ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
7872 ** identity of the database connection (the blocking connection) that
7873 ** has locked the required resource is stored internally. ^After an
7874 ** application receives an SQLITE_LOCKED error, it may call the
7875 ** sqlite3_unlock_notify() method with the blocked connection handle as
7876 ** the first argument to register for a callback that will be invoked
7877 ** when the blocking connections current transaction is concluded. ^The
7878 ** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
7879 ** call that concludes the blocking connections transaction.
7880 **
7881 ** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
7882 ** there is a chance that the blocking connection will have already
7883 ** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
7884 ** If this happens, then the specified callback is invoked immediately,
7885 ** from within the call to sqlite3_unlock_notify().)^
7886 **
7887 ** ^If the blocked connection is attempting to obtain a write-lock on a
7888 ** shared-cache table, and more than one other connection currently holds
7889 ** a read-lock on the same table, then SQLite arbitrarily selects one of
7890 ** the other connections to use as the blocking connection.
7891 **
7892 ** ^(There may be at most one unlock-notify callback registered by a
7893 ** blocked connection. If sqlite3_unlock_notify() is called when the
7894 ** blocked connection already has a registered unlock-notify callback,
7895 ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
7896 ** called with a NULL pointer as its second argument, then any existing
7897 ** unlock-notify callback is canceled. ^The blocked connections
7898 ** unlock-notify callback may also be canceled by closing the blocked
7899 ** connection using [sqlite3_close()].
7900 **
7901 ** The unlock-notify callback is not reentrant. If an application invokes
7902 ** any sqlite3_xxx API functions from within an unlock-notify callback, a
7903 ** crash or deadlock may be the result.
7904 **
7905 ** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
7906 ** returns SQLITE_OK.
7907 **
7908 ** <b>Callback Invocation Details</b>
7909 **
7910 ** When an unlock-notify callback is registered, the application provides a
7911 ** single void* pointer that is passed to the callback when it is invoked.
7912 ** However, the signature of the callback function allows SQLite to pass
7913 ** it an array of void* context pointers. The first argument passed to
7914 ** an unlock-notify callback is a pointer to an array of void* pointers,
7915 ** and the second is the number of entries in the array.
7916 **
7917 ** When a blocking connections transaction is concluded, there may be
7918 ** more than one blocked connection that has registered for an unlock-notify
7919 ** callback. ^If two or more such blocked connections have specified the
7920 ** same callback function, then instead of invoking the callback function
7921 ** multiple times, it is invoked once with the set of void* context pointers
7922 ** specified by the blocked connections bundled together into an array.
7923 ** This gives the application an opportunity to prioritize any actions
7924 ** related to the set of unblocked database connections.
7925 **
7926 ** <b>Deadlock Detection</b>
7927 **
7928 ** Assuming that after registering for an unlock-notify callback a
7929 ** database waits for the callback to be issued before taking any further
7930 ** action (a reasonable assumption), then using this API may cause the
7931 ** application to deadlock. For example, if connection X is waiting for
7932 ** connection Y's transaction to be concluded, and similarly connection
7933 ** Y is waiting on connection X's transaction, then neither connection
7934 ** will proceed and the system may remain deadlocked indefinitely.
7935 **
7936 ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
7937 ** detection. ^If a given call to sqlite3_unlock_notify() would put the
7938 ** system in a deadlocked state, then SQLITE_LOCKED is returned and no
7939 ** unlock-notify callback is registered. The system is said to be in
7940 ** a deadlocked state if connection A has registered for an unlock-notify
7941 ** callback on the conclusion of connection B's transaction, and connection
7942 ** B has itself registered for an unlock-notify callback when connection
7943 ** A's transaction is concluded. ^Indirect deadlock is also detected, so
7944 ** the system is also considered to be deadlocked if connection B has
7945 ** registered for an unlock-notify callback on the conclusion of connection
7946 ** C's transaction, where connection C is waiting on connection A. ^Any
7947 ** number of levels of indirection are allowed.
7948 **
7949 ** <b>The "DROP TABLE" Exception</b>
7950 **
7951 ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
7952 ** always appropriate to call sqlite3_unlock_notify(). There is however,
7953 ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
7954 ** SQLite checks if there are any currently executing SELECT statements
7955 ** that belong to the same connection. If there are, SQLITE_LOCKED is
7956 ** returned. In this case there is no "blocking connection", so invoking
7957 ** sqlite3_unlock_notify() results in the unlock-notify callback being
7958 ** invoked immediately. If the application then re-attempts the "DROP TABLE"
7959 ** or "DROP INDEX" query, an infinite loop might be the result.
7960 **
7961 ** One way around this problem is to check the extended error code returned
7962 ** by an sqlite3_step() call. ^(If there is a blocking connection, then the
7963 ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
7964 ** the special "DROP TABLE/INDEX" case, the extended error code is just
7965 ** SQLITE_LOCKED.)^
7966 */
7967 /* Waiting connection */
7968 /* Callback function to invoke */
7969 /* Argument to pass to xNotify */
7970 int sqlite3_unlock_notify(
7971     sqlite3* pBlocked,
7972     void function(void** apArg, int nArg) xNotify,
7973     void* pNotifyArg);
7974 
7975 /*
7976 ** CAPI3REF: String Comparison
7977 **
7978 ** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications
7979 ** and extensions to compare the contents of two buffers containing UTF-8
7980 ** strings in a case-independent fashion, using the same definition of "case
7981 ** independence" that SQLite uses internally when comparing identifiers.
7982 */
7983 int sqlite3_stricmp(const(char)*, const(char)*);
7984 int sqlite3_strnicmp(const(char)*, const(char)*, int);
7985 
7986 /*
7987 ** CAPI3REF: String Globbing
7988 *
7989 ** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if
7990 ** string X matches the [GLOB] pattern P.
7991 ** ^The definition of [GLOB] pattern matching used in
7992 ** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
7993 ** SQL dialect understood by SQLite.  ^The [sqlite3_strglob(P,X)] function
7994 ** is case sensitive.
7995 **
7996 ** Note that this routine returns zero on a match and non-zero if the strings
7997 ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
7998 **
7999 ** See also: [sqlite3_strlike()].
8000 */
8001 int sqlite3_strglob(const(char)* zGlob, const(char)* zStr);
8002 
8003 /*
8004 ** CAPI3REF: String LIKE Matching
8005 *
8006 ** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if
8007 ** string X matches the [LIKE] pattern P with escape character E.
8008 ** ^The definition of [LIKE] pattern matching used in
8009 ** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E"
8010 ** operator in the SQL dialect understood by SQLite.  ^For "X LIKE P" without
8011 ** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0.
8012 ** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case
8013 ** insensitive - equivalent upper and lower case ASCII characters match
8014 ** one another.
8015 **
8016 ** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though
8017 ** only ASCII characters are case folded.
8018 **
8019 ** Note that this routine returns zero on a match and non-zero if the strings
8020 ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
8021 **
8022 ** See also: [sqlite3_strglob()].
8023 */
8024 int sqlite3_strlike(const(char)* zGlob, const(char)* zStr, uint cEsc);
8025 
8026 /*
8027 ** CAPI3REF: Error Logging Interface
8028 **
8029 ** ^The [sqlite3_log()] interface writes a message into the [error log]
8030 ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
8031 ** ^If logging is enabled, the zFormat string and subsequent arguments are
8032 ** used with [sqlite3_snprintf()] to generate the final output string.
8033 **
8034 ** The sqlite3_log() interface is intended for use by extensions such as
8035 ** virtual tables, collating functions, and SQL functions.  While there is
8036 ** nothing to prevent an application from calling sqlite3_log(), doing so
8037 ** is considered bad form.
8038 **
8039 ** The zFormat string must not be NULL.
8040 **
8041 ** To avoid deadlocks and other threading problems, the sqlite3_log() routine
8042 ** will not use dynamically allocated memory.  The log message is stored in
8043 ** a fixed-length buffer on the stack.  If the log message is longer than
8044 ** a few hundred characters, it will be truncated to the length of the
8045 ** buffer.
8046 */
8047 void sqlite3_log(int iErrCode, const(char)* zFormat, ...);
8048 
8049 /*
8050 ** CAPI3REF: Write-Ahead Log Commit Hook
8051 ** METHOD: sqlite3
8052 **
8053 ** ^The [sqlite3_wal_hook()] function is used to register a callback that
8054 ** is invoked each time data is committed to a database in wal mode.
8055 **
8056 ** ^(The callback is invoked by SQLite after the commit has taken place and
8057 ** the associated write-lock on the database released)^, so the implementation
8058 ** may read, write or [checkpoint] the database as required.
8059 **
8060 ** ^The first parameter passed to the callback function when it is invoked
8061 ** is a copy of the third parameter passed to sqlite3_wal_hook() when
8062 ** registering the callback. ^The second is a copy of the database handle.
8063 ** ^The third parameter is the name of the database that was written to -
8064 ** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
8065 ** is the number of pages currently in the write-ahead log file,
8066 ** including those that were just committed.
8067 **
8068 ** The callback function should normally return [SQLITE_OK].  ^If an error
8069 ** code is returned, that error will propagate back up through the
8070 ** SQLite code base to cause the statement that provoked the callback
8071 ** to report an error, though the commit will have still occurred. If the
8072 ** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
8073 ** that does not correspond to any valid SQLite error code, the results
8074 ** are undefined.
8075 **
8076 ** A single database handle may have at most a single write-ahead log callback
8077 ** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
8078 ** previously registered write-ahead log callback. ^Note that the
8079 ** [sqlite3_wal_autocheckpoint()] interface and the
8080 ** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
8081 ** overwrite any prior [sqlite3_wal_hook()] settings.
8082 */
8083 void* sqlite3_wal_hook(
8084     sqlite3*,
8085     int function(void*, sqlite3*, const(char)*, int),
8086     void*);
8087 
8088 /*
8089 ** CAPI3REF: Configure an auto-checkpoint
8090 ** METHOD: sqlite3
8091 **
8092 ** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
8093 ** [sqlite3_wal_hook()] that causes any database on [database connection] D
8094 ** to automatically [checkpoint]
8095 ** after committing a transaction if there are N or
8096 ** more frames in the [write-ahead log] file.  ^Passing zero or
8097 ** a negative value as the nFrame parameter disables automatic
8098 ** checkpoints entirely.
8099 **
8100 ** ^The callback registered by this function replaces any existing callback
8101 ** registered using [sqlite3_wal_hook()].  ^Likewise, registering a callback
8102 ** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
8103 ** configured by this function.
8104 **
8105 ** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
8106 ** from SQL.
8107 **
8108 ** ^Checkpoints initiated by this mechanism are
8109 ** [sqlite3_wal_checkpoint_v2|PASSIVE].
8110 **
8111 ** ^Every new [database connection] defaults to having the auto-checkpoint
8112 ** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
8113 ** pages.  The use of this interface
8114 ** is only necessary if the default setting is found to be suboptimal
8115 ** for a particular application.
8116 */
8117 int sqlite3_wal_autocheckpoint(sqlite3* db, int N);
8118 
8119 /*
8120 ** CAPI3REF: Checkpoint a database
8121 ** METHOD: sqlite3
8122 **
8123 ** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to
8124 ** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^
8125 **
8126 ** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the
8127 ** [write-ahead log] for database X on [database connection] D to be
8128 ** transferred into the database file and for the write-ahead log to
8129 ** be reset.  See the [checkpointing] documentation for addition
8130 ** information.
8131 **
8132 ** This interface used to be the only way to cause a checkpoint to
8133 ** occur.  But then the newer and more powerful [sqlite3_wal_checkpoint_v2()]
8134 ** interface was added.  This interface is retained for backwards
8135 ** compatibility and as a convenience for applications that need to manually
8136 ** start a callback but which do not need the full power (and corresponding
8137 ** complication) of [sqlite3_wal_checkpoint_v2()].
8138 */
8139 int sqlite3_wal_checkpoint(sqlite3* db, const(char)* zDb);
8140 
8141 /*
8142 ** CAPI3REF: Checkpoint a database
8143 ** METHOD: sqlite3
8144 **
8145 ** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint
8146 ** operation on database X of [database connection] D in mode M.  Status
8147 ** information is written back into integers pointed to by L and C.)^
8148 ** ^(The M parameter must be a valid [checkpoint mode]:)^
8149 **
8150 ** <dl>
8151 ** <dt>SQLITE_CHECKPOINT_PASSIVE<dd>
8152 **   ^Checkpoint as many frames as possible without waiting for any database
8153 **   readers or writers to finish, then sync the database file if all frames
8154 **   in the log were checkpointed. ^The [busy-handler callback]
8155 **   is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode.
8156 **   ^On the other hand, passive mode might leave the checkpoint unfinished
8157 **   if there are concurrent readers or writers.
8158 **
8159 ** <dt>SQLITE_CHECKPOINT_FULL<dd>
8160 **   ^This mode blocks (it invokes the
8161 **   [sqlite3_busy_handler|busy-handler callback]) until there is no
8162 **   database writer and all readers are reading from the most recent database
8163 **   snapshot. ^It then checkpoints all frames in the log file and syncs the
8164 **   database file. ^This mode blocks new database writers while it is pending,
8165 **   but new database readers are allowed to continue unimpeded.
8166 **
8167 ** <dt>SQLITE_CHECKPOINT_RESTART<dd>
8168 **   ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition
8169 **   that after checkpointing the log file it blocks (calls the
8170 **   [busy-handler callback])
8171 **   until all readers are reading from the database file only. ^This ensures
8172 **   that the next writer will restart the log file from the beginning.
8173 **   ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new
8174 **   database writer attempts while it is pending, but does not impede readers.
8175 **
8176 ** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd>
8177 **   ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the
8178 **   addition that it also truncates the log file to zero bytes just prior
8179 **   to a successful return.
8180 ** </dl>
8181 **
8182 ** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in
8183 ** the log file or to -1 if the checkpoint could not run because
8184 ** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not
8185 ** NULL,then *pnCkpt is set to the total number of checkpointed frames in the
8186 ** log file (including any that were already checkpointed before the function
8187 ** was called) or to -1 if the checkpoint could not run due to an error or
8188 ** because the database is not in WAL mode. ^Note that upon successful
8189 ** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been
8190 ** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero.
8191 **
8192 ** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If
8193 ** any other process is running a checkpoint operation at the same time, the
8194 ** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a
8195 ** busy-handler configured, it will not be invoked in this case.
8196 **
8197 ** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the
8198 ** exclusive "writer" lock on the database file. ^If the writer lock cannot be
8199 ** obtained immediately, and a busy-handler is configured, it is invoked and
8200 ** the writer lock retried until either the busy-handler returns 0 or the lock
8201 ** is successfully obtained. ^The busy-handler is also invoked while waiting for
8202 ** database readers as described above. ^If the busy-handler returns 0 before
8203 ** the writer lock is obtained or while waiting for database readers, the
8204 ** checkpoint operation proceeds from that point in the same way as
8205 ** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible
8206 ** without blocking any further. ^SQLITE_BUSY is returned in this case.
8207 **
8208 ** ^If parameter zDb is NULL or points to a zero length string, then the
8209 ** specified operation is attempted on all WAL databases [attached] to
8210 ** [database connection] db.  In this case the
8211 ** values written to output parameters *pnLog and *pnCkpt are undefined. ^If
8212 ** an SQLITE_BUSY error is encountered when processing one or more of the
8213 ** attached WAL databases, the operation is still attempted on any remaining
8214 ** attached databases and SQLITE_BUSY is returned at the end. ^If any other
8215 ** error occurs while processing an attached database, processing is abandoned
8216 ** and the error code is returned to the caller immediately. ^If no error
8217 ** (SQLITE_BUSY or otherwise) is encountered while processing the attached
8218 ** databases, SQLITE_OK is returned.
8219 **
8220 ** ^If database zDb is the name of an attached database that is not in WAL
8221 ** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If
8222 ** zDb is not NULL (or a zero length string) and is not the name of any
8223 ** attached database, SQLITE_ERROR is returned to the caller.
8224 **
8225 ** ^Unless it returns SQLITE_MISUSE,
8226 ** the sqlite3_wal_checkpoint_v2() interface
8227 ** sets the error information that is queried by
8228 ** [sqlite3_errcode()] and [sqlite3_errmsg()].
8229 **
8230 ** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface
8231 ** from SQL.
8232 */
8233 /* Database handle */
8234 /* Name of attached database (or NULL) */
8235 /* SQLITE_CHECKPOINT_* value */
8236 /* OUT: Size of WAL log in frames */
8237 /* OUT: Total number of frames checkpointed */
8238 int sqlite3_wal_checkpoint_v2(
8239     sqlite3* db,
8240     const(char)* zDb,
8241     int eMode,
8242     int* pnLog,
8243     int* pnCkpt);
8244 
8245 /*
8246 ** CAPI3REF: Checkpoint Mode Values
8247 ** KEYWORDS: {checkpoint mode}
8248 **
8249 ** These constants define all valid values for the "checkpoint mode" passed
8250 ** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface.
8251 ** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the
8252 ** meaning of each of these checkpoint modes.
8253 */
8254 enum SQLITE_CHECKPOINT_PASSIVE = 0; /* Do as much as possible w/o blocking */
8255 enum SQLITE_CHECKPOINT_FULL = 1; /* Wait for writers, then checkpoint */
8256 enum SQLITE_CHECKPOINT_RESTART = 2; /* Like FULL but wait for for readers */
8257 enum SQLITE_CHECKPOINT_TRUNCATE = 3; /* Like RESTART but also truncate WAL */
8258 
8259 /*
8260 ** CAPI3REF: Virtual Table Interface Configuration
8261 **
8262 ** This function may be called by either the [xConnect] or [xCreate] method
8263 ** of a [virtual table] implementation to configure
8264 ** various facets of the virtual table interface.
8265 **
8266 ** If this interface is invoked outside the context of an xConnect or
8267 ** xCreate virtual table method then the behavior is undefined.
8268 **
8269 ** At present, there is only one option that may be configured using
8270 ** this function. (See [SQLITE_VTAB_CONSTRAINT_SUPPORT].)  Further options
8271 ** may be added in the future.
8272 */
8273 int sqlite3_vtab_config(sqlite3*, int op, ...);
8274 
8275 /*
8276 ** CAPI3REF: Virtual Table Configuration Options
8277 **
8278 ** These macros define the various options to the
8279 ** [sqlite3_vtab_config()] interface that [virtual table] implementations
8280 ** can use to customize and optimize their behavior.
8281 **
8282 ** <dl>
8283 ** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT
8284 ** <dd>Calls of the form
8285 ** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,
8286 ** where X is an integer.  If X is zero, then the [virtual table] whose
8287 ** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not
8288 ** support constraints.  In this configuration (which is the default) if
8289 ** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire
8290 ** statement is rolled back as if [ON CONFLICT | OR ABORT] had been
8291 ** specified as part of the users SQL statement, regardless of the actual
8292 ** ON CONFLICT mode specified.
8293 **
8294 ** If X is non-zero, then the virtual table implementation guarantees
8295 ** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before
8296 ** any modifications to internal or persistent data structures have been made.
8297 ** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite
8298 ** is able to roll back a statement or database transaction, and abandon
8299 ** or continue processing the current SQL statement as appropriate.
8300 ** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns
8301 ** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode
8302 ** had been ABORT.
8303 **
8304 ** Virtual table implementations that are required to handle OR REPLACE
8305 ** must do so within the [xUpdate] method. If a call to the
8306 ** [sqlite3_vtab_on_conflict()] function indicates that the current ON
8307 ** CONFLICT policy is REPLACE, the virtual table implementation should
8308 ** silently replace the appropriate rows within the xUpdate callback and
8309 ** return SQLITE_OK. Or, if this is not possible, it may return
8310 ** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT
8311 ** constraint handling.
8312 ** </dl>
8313 */
8314 enum SQLITE_VTAB_CONSTRAINT_SUPPORT = 1;
8315 
8316 /*
8317 ** CAPI3REF: Determine The Virtual Table Conflict Policy
8318 **
8319 ** This function may only be called from within a call to the [xUpdate] method
8320 ** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The
8321 ** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],
8322 ** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode
8323 ** of the SQL statement that triggered the call to the [xUpdate] method of the
8324 ** [virtual table].
8325 */
8326 int sqlite3_vtab_on_conflict(sqlite3*);
8327 
8328 /*
8329 ** CAPI3REF: Conflict resolution modes
8330 ** KEYWORDS: {conflict resolution mode}
8331 **
8332 ** These constants are returned by [sqlite3_vtab_on_conflict()] to
8333 ** inform a [virtual table] implementation what the [ON CONFLICT] mode
8334 ** is for the SQL statement being evaluated.
8335 **
8336 ** Note that the [SQLITE_IGNORE] constant is also used as a potential
8337 ** return value from the [sqlite3_set_authorizer()] callback and that
8338 ** [SQLITE_ABORT] is also a [result code].
8339 */
8340 enum SQLITE_ROLLBACK = 1;
8341 /* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
8342 enum SQLITE_FAIL = 3;
8343 /* #define SQLITE_ABORT 4  // Also an error code */
8344 enum SQLITE_REPLACE = 5;
8345 
8346 /*
8347 ** CAPI3REF: Prepared Statement Scan Status Opcodes
8348 ** KEYWORDS: {scanstatus options}
8349 **
8350 ** The following constants can be used for the T parameter to the
8351 ** [sqlite3_stmt_scanstatus(S,X,T,V)] interface.  Each constant designates a
8352 ** different metric for sqlite3_stmt_scanstatus() to return.
8353 **
8354 ** When the value returned to V is a string, space to hold that string is
8355 ** managed by the prepared statement S and will be automatically freed when
8356 ** S is finalized.
8357 **
8358 ** <dl>
8359 ** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt>
8360 ** <dd>^The [sqlite3_int64] variable pointed to by the T parameter will be
8361 ** set to the total number of times that the X-th loop has run.</dd>
8362 **
8363 ** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt>
8364 ** <dd>^The [sqlite3_int64] variable pointed to by the T parameter will be set
8365 ** to the total number of rows examined by all iterations of the X-th loop.</dd>
8366 **
8367 ** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt>
8368 ** <dd>^The "double" variable pointed to by the T parameter will be set to the
8369 ** query planner's estimate for the average number of rows output from each
8370 ** iteration of the X-th loop.  If the query planner's estimates was accurate,
8371 ** then this value will approximate the quotient NVISIT/NLOOP and the
8372 ** product of this value for all prior loops with the same SELECTID will
8373 ** be the NLOOP value for the current loop.
8374 **
8375 ** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt>
8376 ** <dd>^The "const char *" variable pointed to by the T parameter will be set
8377 ** to a zero-terminated UTF-8 string containing the name of the index or table
8378 ** used for the X-th loop.
8379 **
8380 ** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt>
8381 ** <dd>^The "const char *" variable pointed to by the T parameter will be set
8382 ** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN]
8383 ** description for the X-th loop.
8384 **
8385 ** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECT</dt>
8386 ** <dd>^The "int" variable pointed to by the T parameter will be set to the
8387 ** "select-id" for the X-th loop.  The select-id identifies which query or
8388 ** subquery the loop is part of.  The main query has a select-id of zero.
8389 ** The select-id is the same value as is output in the first column
8390 ** of an [EXPLAIN QUERY PLAN] query.
8391 ** </dl>
8392 */
8393 enum SQLITE_SCANSTAT_NLOOP = 0;
8394 enum SQLITE_SCANSTAT_NVISIT = 1;
8395 enum SQLITE_SCANSTAT_EST = 2;
8396 enum SQLITE_SCANSTAT_NAME = 3;
8397 enum SQLITE_SCANSTAT_EXPLAIN = 4;
8398 enum SQLITE_SCANSTAT_SELECTID = 5;
8399 
8400 /*
8401 ** CAPI3REF: Prepared Statement Scan Status
8402 ** METHOD: sqlite3_stmt
8403 **
8404 ** This interface returns information about the predicted and measured
8405 ** performance for pStmt.  Advanced applications can use this
8406 ** interface to compare the predicted and the measured performance and
8407 ** issue warnings and/or rerun [ANALYZE] if discrepancies are found.
8408 **
8409 ** Since this interface is expected to be rarely used, it is only
8410 ** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS]
8411 ** compile-time option.
8412 **
8413 ** The "iScanStatusOp" parameter determines which status information to return.
8414 ** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior
8415 ** of this interface is undefined.
8416 ** ^The requested measurement is written into a variable pointed to by
8417 ** the "pOut" parameter.
8418 ** Parameter "idx" identifies the specific loop to retrieve statistics for.
8419 ** Loops are numbered starting from zero. ^If idx is out of range - less than
8420 ** zero or greater than or equal to the total number of loops used to implement
8421 ** the statement - a non-zero value is returned and the variable that pOut
8422 ** points to is unchanged.
8423 **
8424 ** ^Statistics might not be available for all loops in all statements. ^In cases
8425 ** where there exist loops with no available statistics, this function behaves
8426 ** as if the loop did not exist - it returns non-zero and leave the variable
8427 ** that pOut points to unchanged.
8428 **
8429 ** See also: [sqlite3_stmt_scanstatus_reset()]
8430 */
8431 /* Prepared statement for which info desired */
8432 /* Index of loop to report on */
8433 /* Information desired.  SQLITE_SCANSTAT_* */
8434 /* Result written here */
8435 int sqlite3_stmt_scanstatus(
8436     sqlite3_stmt* pStmt,
8437     int idx,
8438     int iScanStatusOp,
8439     void* pOut);
8440 
8441 /*
8442 ** CAPI3REF: Zero Scan-Status Counters
8443 ** METHOD: sqlite3_stmt
8444 **
8445 ** ^Zero all [sqlite3_stmt_scanstatus()] related event counters.
8446 **
8447 ** This API is only available if the library is built with pre-processor
8448 ** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined.
8449 */
8450 void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*);
8451 
8452 /*
8453 ** CAPI3REF: Flush caches to disk mid-transaction
8454 **
8455 ** ^If a write-transaction is open on [database connection] D when the
8456 ** [sqlite3_db_cacheflush(D)] interface invoked, any dirty
8457 ** pages in the pager-cache that are not currently in use are written out
8458 ** to disk. A dirty page may be in use if a database cursor created by an
8459 ** active SQL statement is reading from it, or if it is page 1 of a database
8460 ** file (page 1 is always "in use").  ^The [sqlite3_db_cacheflush(D)]
8461 ** interface flushes caches for all schemas - "main", "temp", and
8462 ** any [attached] databases.
8463 **
8464 ** ^If this function needs to obtain extra database locks before dirty pages
8465 ** can be flushed to disk, it does so. ^If those locks cannot be obtained
8466 ** immediately and there is a busy-handler callback configured, it is invoked
8467 ** in the usual manner. ^If the required lock still cannot be obtained, then
8468 ** the database is skipped and an attempt made to flush any dirty pages
8469 ** belonging to the next (if any) database. ^If any databases are skipped
8470 ** because locks cannot be obtained, but no other error occurs, this
8471 ** function returns SQLITE_BUSY.
8472 **
8473 ** ^If any other error occurs while flushing dirty pages to disk (for
8474 ** example an IO error or out-of-memory condition), then processing is
8475 ** abandoned and an SQLite [error code] is returned to the caller immediately.
8476 **
8477 ** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK.
8478 **
8479 ** ^This function does not set the database handle error code or message
8480 ** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions.
8481 */
8482 int sqlite3_db_cacheflush(sqlite3*);
8483 
8484 /*
8485 ** CAPI3REF: The pre-update hook.
8486 **
8487 ** ^These interfaces are only available if SQLite is compiled using the
8488 ** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option.
8489 **
8490 ** ^The [sqlite3_preupdate_hook()] interface registers a callback function
8491 ** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation
8492 ** on a database table.
8493 ** ^At most one preupdate hook may be registered at a time on a single
8494 ** [database connection]; each call to [sqlite3_preupdate_hook()] overrides
8495 ** the previous setting.
8496 ** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()]
8497 ** with a NULL pointer as the second parameter.
8498 ** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as
8499 ** the first parameter to callbacks.
8500 **
8501 ** ^The preupdate hook only fires for changes to real database tables; the
8502 ** preupdate hook is not invoked for changes to [virtual tables] or to
8503 ** system tables like sqlite_master or sqlite_stat1.
8504 **
8505 ** ^The second parameter to the preupdate callback is a pointer to
8506 ** the [database connection] that registered the preupdate hook.
8507 ** ^The third parameter to the preupdate callback is one of the constants
8508 ** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the
8509 ** kind of update operation that is about to occur.
8510 ** ^(The fourth parameter to the preupdate callback is the name of the
8511 ** database within the database connection that is being modified.  This
8512 ** will be "main" for the main database or "temp" for TEMP tables or
8513 ** the name given after the AS keyword in the [ATTACH] statement for attached
8514 ** databases.)^
8515 ** ^The fifth parameter to the preupdate callback is the name of the
8516 ** table that is being modified.
8517 **
8518 ** For an UPDATE or DELETE operation on a [rowid table], the sixth
8519 ** parameter passed to the preupdate callback is the initial [rowid] of the
8520 ** row being modified or deleted. For an INSERT operation on a rowid table,
8521 ** or any operation on a WITHOUT ROWID table, the value of the sixth
8522 ** parameter is undefined. For an INSERT or UPDATE on a rowid table the
8523 ** seventh parameter is the final rowid value of the row being inserted
8524 ** or updated. The value of the seventh parameter passed to the callback
8525 ** function is not defined for operations on WITHOUT ROWID tables, or for
8526 ** INSERT operations on rowid tables.
8527 **
8528 ** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()],
8529 ** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces
8530 ** provide additional information about a preupdate event. These routines
8531 ** may only be called from within a preupdate callback.  Invoking any of
8532 ** these routines from outside of a preupdate callback or with a
8533 ** [database connection] pointer that is different from the one supplied
8534 ** to the preupdate callback results in undefined and probably undesirable
8535 ** behavior.
8536 **
8537 ** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns
8538 ** in the row that is being inserted, updated, or deleted.
8539 **
8540 ** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to
8541 ** a [protected sqlite3_value] that contains the value of the Nth column of
8542 ** the table row before it is updated.  The N parameter must be between 0
8543 ** and one less than the number of columns or the behavior will be
8544 ** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE
8545 ** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the
8546 ** behavior is undefined.  The [sqlite3_value] that P points to
8547 ** will be destroyed when the preupdate callback returns.
8548 **
8549 ** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to
8550 ** a [protected sqlite3_value] that contains the value of the Nth column of
8551 ** the table row after it is updated.  The N parameter must be between 0
8552 ** and one less than the number of columns or the behavior will be
8553 ** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE
8554 ** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the
8555 ** behavior is undefined.  The [sqlite3_value] that P points to
8556 ** will be destroyed when the preupdate callback returns.
8557 **
8558 ** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate
8559 ** callback was invoked as a result of a direct insert, update, or delete
8560 ** operation; or 1 for inserts, updates, or deletes invoked by top-level
8561 ** triggers; or 2 for changes resulting from triggers called by top-level
8562 ** triggers; and so forth.
8563 **
8564 ** See also:  [sqlite3_update_hook()]
8565 */
8566 
8567 /* Copy of third arg to preupdate_hook() */
8568 /* Database handle */
8569 /* SQLITE_UPDATE, DELETE or INSERT */
8570 /* Database name */
8571 /* Table name */
8572 /* Rowid of row about to be deleted/updated */
8573 /* New rowid value (for a rowid UPDATE) */
8574 
8575 /*
8576 ** CAPI3REF: Low-level system error code
8577 **
8578 ** ^Attempt to return the underlying operating system error code or error
8579 ** number that caused the most recent I/O error or failure to open a file.
8580 ** The return value is OS-dependent.  For example, on unix systems, after
8581 ** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be
8582 ** called to get back the underlying "errno" that caused the problem, such
8583 ** as ENOSPC, EAUTH, EISDIR, and so forth.
8584 */
8585 int sqlite3_system_errno(sqlite3*);
8586 
8587 /*
8588 ** CAPI3REF: Database Snapshot
8589 ** KEYWORDS: {snapshot} {sqlite3_snapshot}
8590 ** EXPERIMENTAL
8591 **
8592 ** An instance of the snapshot object records the state of a [WAL mode]
8593 ** database for some specific point in history.
8594 **
8595 ** In [WAL mode], multiple [database connections] that are open on the
8596 ** same database file can each be reading a different historical version
8597 ** of the database file.  When a [database connection] begins a read
8598 ** transaction, that connection sees an unchanging copy of the database
8599 ** as it existed for the point in time when the transaction first started.
8600 ** Subsequent changes to the database from other connections are not seen
8601 ** by the reader until a new read transaction is started.
8602 **
8603 ** The sqlite3_snapshot object records state information about an historical
8604 ** version of the database file so that it is possible to later open a new read
8605 ** transaction that sees that historical version of the database rather than
8606 ** the most recent version.
8607 **
8608 ** The constructor for this object is [sqlite3_snapshot_get()].  The
8609 ** [sqlite3_snapshot_open()] method causes a fresh read transaction to refer
8610 ** to an historical snapshot (if possible).  The destructor for
8611 ** sqlite3_snapshot objects is [sqlite3_snapshot_free()].
8612 */
8613 struct sqlite3_snapshot
8614 {
8615     ubyte[48] hidden;
8616 }
8617 
8618 /*
8619 ** CAPI3REF: Record A Database Snapshot
8620 ** EXPERIMENTAL
8621 **
8622 ** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a
8623 ** new [sqlite3_snapshot] object that records the current state of
8624 ** schema S in database connection D.  ^On success, the
8625 ** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly
8626 ** created [sqlite3_snapshot] object into *P and returns SQLITE_OK.
8627 ** If there is not already a read-transaction open on schema S when
8628 ** this function is called, one is opened automatically.
8629 **
8630 ** The following must be true for this function to succeed. If any of
8631 ** the following statements are false when sqlite3_snapshot_get() is
8632 ** called, SQLITE_ERROR is returned. The final value of *P is undefined
8633 ** in this case.
8634 **
8635 ** <ul>
8636 **   <li> The database handle must be in [autocommit mode].
8637 **
8638 **   <li> Schema S of [database connection] D must be a [WAL mode] database.
8639 **
8640 **   <li> There must not be a write transaction open on schema S of database
8641 **        connection D.
8642 **
8643 **   <li> One or more transactions must have been written to the current wal
8644 **        file since it was created on disk (by any connection). This means
8645 **        that a snapshot cannot be taken on a wal mode database with no wal
8646 **        file immediately after it is first opened. At least one transaction
8647 **        must be written to it first.
8648 ** </ul>
8649 **
8650 ** This function may also return SQLITE_NOMEM.  If it is called with the
8651 ** database handle in autocommit mode but fails for some other reason,
8652 ** whether or not a read transaction is opened on schema S is undefined.
8653 **
8654 ** The [sqlite3_snapshot] object returned from a successful call to
8655 ** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()]
8656 ** to avoid a memory leak.
8657 **
8658 ** The [sqlite3_snapshot_get()] interface is only available when the
8659 ** SQLITE_ENABLE_SNAPSHOT compile-time option is used.
8660 */
8661 int sqlite3_snapshot_get(
8662     sqlite3* db,
8663     const(char)* zSchema,
8664     sqlite3_snapshot** ppSnapshot);
8665 
8666 /*
8667 ** CAPI3REF: Start a read transaction on an historical snapshot
8668 ** EXPERIMENTAL
8669 **
8670 ** ^The [sqlite3_snapshot_open(D,S,P)] interface starts a
8671 ** read transaction for schema S of
8672 ** [database connection] D such that the read transaction
8673 ** refers to historical [snapshot] P, rather than the most
8674 ** recent change to the database.
8675 ** ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK on success
8676 ** or an appropriate [error code] if it fails.
8677 **
8678 ** ^In order to succeed, a call to [sqlite3_snapshot_open(D,S,P)] must be
8679 ** the first operation following the [BEGIN] that takes the schema S
8680 ** out of [autocommit mode].
8681 ** ^In other words, schema S must not currently be in
8682 ** a transaction for [sqlite3_snapshot_open(D,S,P)] to work, but the
8683 ** database connection D must be out of [autocommit mode].
8684 ** ^A [snapshot] will fail to open if it has been overwritten by a
8685 ** [checkpoint].
8686 ** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the
8687 ** database connection D does not know that the database file for
8688 ** schema S is in [WAL mode].  A database connection might not know
8689 ** that the database file is in [WAL mode] if there has been no prior
8690 ** I/O on that database connection, or if the database entered [WAL mode]
8691 ** after the most recent I/O on the database connection.)^
8692 ** (Hint: Run "[PRAGMA application_id]" against a newly opened
8693 ** database connection in order to make it ready to use snapshots.)
8694 **
8695 ** The [sqlite3_snapshot_open()] interface is only available when the
8696 ** SQLITE_ENABLE_SNAPSHOT compile-time option is used.
8697 */
8698 int sqlite3_snapshot_open(
8699     sqlite3* db,
8700     const(char)* zSchema,
8701     sqlite3_snapshot* pSnapshot);
8702 
8703 /*
8704 ** CAPI3REF: Destroy a snapshot
8705 ** EXPERIMENTAL
8706 **
8707 ** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P.
8708 ** The application must eventually free every [sqlite3_snapshot] object
8709 ** using this routine to avoid a memory leak.
8710 **
8711 ** The [sqlite3_snapshot_free()] interface is only available when the
8712 ** SQLITE_ENABLE_SNAPSHOT compile-time option is used.
8713 */
8714 void sqlite3_snapshot_free(sqlite3_snapshot*);
8715 
8716 /*
8717 ** CAPI3REF: Compare the ages of two snapshot handles.
8718 ** EXPERIMENTAL
8719 **
8720 ** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages
8721 ** of two valid snapshot handles.
8722 **
8723 ** If the two snapshot handles are not associated with the same database
8724 ** file, the result of the comparison is undefined.
8725 **
8726 ** Additionally, the result of the comparison is only valid if both of the
8727 ** snapshot handles were obtained by calling sqlite3_snapshot_get() since the
8728 ** last time the wal file was deleted. The wal file is deleted when the
8729 ** database is changed back to rollback mode or when the number of database
8730 ** clients drops to zero. If either snapshot handle was obtained before the
8731 ** wal file was last deleted, the value returned by this function
8732 ** is undefined.
8733 **
8734 ** Otherwise, this API returns a negative value if P1 refers to an older
8735 ** snapshot than P2, zero if the two handles refer to the same database
8736 ** snapshot, and a positive value if P1 is a newer snapshot than P2.
8737 */
8738 int sqlite3_snapshot_cmp(sqlite3_snapshot* p1, sqlite3_snapshot* p2);
8739 
8740 /*
8741 ** CAPI3REF: Recover snapshots from a wal file
8742 ** EXPERIMENTAL
8743 **
8744 ** If all connections disconnect from a database file but do not perform
8745 ** a checkpoint, the existing wal file is opened along with the database
8746 ** file the next time the database is opened. At this point it is only
8747 ** possible to successfully call sqlite3_snapshot_open() to open the most
8748 ** recent snapshot of the database (the one at the head of the wal file),
8749 ** even though the wal file may contain other valid snapshots for which
8750 ** clients have sqlite3_snapshot handles.
8751 **
8752 ** This function attempts to scan the wal file associated with database zDb
8753 ** of database handle db and make all valid snapshots available to
8754 ** sqlite3_snapshot_open(). It is an error if there is already a read
8755 ** transaction open on the database, or if the database is not a wal mode
8756 ** database.
8757 **
8758 ** SQLITE_OK is returned if successful, or an SQLite error code otherwise.
8759 */
8760 int sqlite3_snapshot_recover(sqlite3* db, const(char)* zDb);
8761 
8762 /*
8763 ** Undo the hack that converts floating point types to integer for
8764 ** builds on processors without floating point support.
8765 */
8766 
8767 /* End of the 'extern "C"' block */
8768 
8769 /* SQLITE3_H */
8770 
8771 /******** Begin file sqlite3rtree.h *********/
8772 /*
8773 ** 2010 August 30
8774 **
8775 ** The author disclaims copyright to this source code.  In place of
8776 ** a legal notice, here is a blessing:
8777 **
8778 **    May you do good and not evil.
8779 **    May you find forgiveness for yourself and forgive others.
8780 **    May you share freely, never taking more than you give.
8781 **
8782 *************************************************************************
8783 */
8784 
8785 /* The double-precision datatype used by RTree depends on the
8786 ** SQLITE_RTREE_INT_ONLY compile-time option.
8787 */
8788 
8789 alias sqlite3_rtree_dbl = double;
8790 
8791 /*
8792 ** Register a geometry callback named zGeom that can be used as part of an
8793 ** R-Tree geometry query as follows:
8794 **
8795 **   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
8796 */
8797 int sqlite3_rtree_geometry_callback(
8798     sqlite3* db,
8799     const(char)* zGeom,
8800     int function(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*, int*) xGeom,
8801     void* pContext);
8802 
8803 /*
8804 ** A pointer to a structure of the following type is passed as the first
8805 ** argument to callbacks registered using rtree_geometry_callback().
8806 */
8807 struct sqlite3_rtree_geometry
8808 {
8809     void* pContext; /* Copy of pContext passed to s_r_g_c() */
8810     int nParam; /* Size of array aParam[] */
8811     sqlite3_rtree_dbl* aParam; /* Parameters passed to SQL geom function */
8812     void* pUser; /* Callback implementation user data */
8813     void function(void*) xDelUser; /* Called by SQLite to clean up pUser */
8814 }
8815 
8816 /*
8817 ** Register a 2nd-generation geometry callback named zScore that can be
8818 ** used as part of an R-Tree geometry query as follows:
8819 **
8820 **   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...)
8821 */
8822 int sqlite3_rtree_query_callback(
8823     sqlite3* db,
8824     const(char)* zQueryFunc,
8825     int function(sqlite3_rtree_query_info*) xQueryFunc,
8826     void* pContext,
8827     void function(void*) xDestructor);
8828 
8829 /*
8830 ** A pointer to a structure of the following type is passed as the
8831 ** argument to scored geometry callback registered using
8832 ** sqlite3_rtree_query_callback().
8833 **
8834 ** Note that the first 5 fields of this structure are identical to
8835 ** sqlite3_rtree_geometry.  This structure is a subclass of
8836 ** sqlite3_rtree_geometry.
8837 */
8838 struct sqlite3_rtree_query_info
8839 {
8840     void* pContext; /* pContext from when function registered */
8841     int nParam; /* Number of function parameters */
8842     sqlite3_rtree_dbl* aParam; /* value of function parameters */
8843     void* pUser; /* callback can use this, if desired */
8844     void function(void*) xDelUser; /* function to free pUser */
8845     sqlite3_rtree_dbl* aCoord; /* Coordinates of node or entry to check */
8846     uint* anQueue; /* Number of pending entries in the queue */
8847     int nCoord; /* Number of coordinates */
8848     int iLevel; /* Level of current node or entry */
8849     int mxLevel; /* The largest iLevel value in the tree */
8850     sqlite3_int64 iRowid; /* Rowid for current entry */
8851     sqlite3_rtree_dbl rParentScore; /* Score of parent node */
8852     int eParentWithin; /* Visibility of parent node */
8853     int eWithin; /* OUT: Visiblity */
8854     sqlite3_rtree_dbl rScore; /* OUT: Write the score here */
8855     /* The following fields are only available in 3.8.11 and later */
8856     sqlite3_value** apSqlParam; /* Original SQL values of parameters */
8857 }
8858 
8859 /*
8860 ** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin.
8861 */
8862 enum NOT_WITHIN = 0; /* Object completely outside of query region */
8863 enum PARTLY_WITHIN = 1; /* Object partially overlaps query region */
8864 enum FULLY_WITHIN = 2; /* Object fully contained within query region */
8865 
8866 /* end of the 'extern "C"' block */
8867 
8868 /* ifndef _SQLITE3RTREE_H_ */
8869 
8870 /******** End of sqlite3rtree.h *********/
8871 /******** Begin file sqlite3session.h *********/
8872 
8873 /*
8874 ** Make sure we can call this stuff from C++.
8875 */
8876 
8877 /*
8878 ** CAPI3REF: Session Object Handle
8879 */
8880 
8881 /*
8882 ** CAPI3REF: Changeset Iterator Handle
8883 */
8884 
8885 /*
8886 ** CAPI3REF: Create A New Session Object
8887 **
8888 ** Create a new session object attached to database handle db. If successful,
8889 ** a pointer to the new object is written to *ppSession and SQLITE_OK is
8890 ** returned. If an error occurs, *ppSession is set to NULL and an SQLite
8891 ** error code (e.g. SQLITE_NOMEM) is returned.
8892 **
8893 ** It is possible to create multiple session objects attached to a single
8894 ** database handle.
8895 **
8896 ** Session objects created using this function should be deleted using the
8897 ** [sqlite3session_delete()] function before the database handle that they
8898 ** are attached to is itself closed. If the database handle is closed before
8899 ** the session object is deleted, then the results of calling any session
8900 ** module function, including [sqlite3session_delete()] on the session object
8901 ** are undefined.
8902 **
8903 ** Because the session module uses the [sqlite3_preupdate_hook()] API, it
8904 ** is not possible for an application to register a pre-update hook on a
8905 ** database handle that has one or more session objects attached. Nor is
8906 ** it possible to create a session object attached to a database handle for
8907 ** which a pre-update hook is already defined. The results of attempting
8908 ** either of these things are undefined.
8909 **
8910 ** The session object will be used to create changesets for tables in
8911 ** database zDb, where zDb is either "main", or "temp", or the name of an
8912 ** attached database. It is not an error if database zDb is not attached
8913 ** to the database when the session object is created.
8914 */
8915 
8916 /* Database handle */
8917 /* Name of db (e.g. "main") */
8918 /* OUT: New session object */
8919 
8920 /*
8921 ** CAPI3REF: Delete A Session Object
8922 **
8923 ** Delete a session object previously allocated using
8924 ** [sqlite3session_create()]. Once a session object has been deleted, the
8925 ** results of attempting to use pSession with any other session module
8926 ** function are undefined.
8927 **
8928 ** Session objects must be deleted before the database handle to which they
8929 ** are attached is closed. Refer to the documentation for
8930 ** [sqlite3session_create()] for details.
8931 */
8932 
8933 /*
8934 ** CAPI3REF: Enable Or Disable A Session Object
8935 **
8936 ** Enable or disable the recording of changes by a session object. When
8937 ** enabled, a session object records changes made to the database. When
8938 ** disabled - it does not. A newly created session object is enabled.
8939 ** Refer to the documentation for [sqlite3session_changeset()] for further
8940 ** details regarding how enabling and disabling a session object affects
8941 ** the eventual changesets.
8942 **
8943 ** Passing zero to this function disables the session. Passing a value
8944 ** greater than zero enables it. Passing a value less than zero is a
8945 ** no-op, and may be used to query the current state of the session.
8946 **
8947 ** The return value indicates the final state of the session object: 0 if
8948 ** the session is disabled, or 1 if it is enabled.
8949 */
8950 
8951 /*
8952 ** CAPI3REF: Set Or Clear the Indirect Change Flag
8953 **
8954 ** Each change recorded by a session object is marked as either direct or
8955 ** indirect. A change is marked as indirect if either:
8956 **
8957 ** <ul>
8958 **   <li> The session object "indirect" flag is set when the change is
8959 **        made, or
8960 **   <li> The change is made by an SQL trigger or foreign key action
8961 **        instead of directly as a result of a users SQL statement.
8962 ** </ul>
8963 **
8964 ** If a single row is affected by more than one operation within a session,
8965 ** then the change is considered indirect if all operations meet the criteria
8966 ** for an indirect change above, or direct otherwise.
8967 **
8968 ** This function is used to set, clear or query the session object indirect
8969 ** flag.  If the second argument passed to this function is zero, then the
8970 ** indirect flag is cleared. If it is greater than zero, the indirect flag
8971 ** is set. Passing a value less than zero does not modify the current value
8972 ** of the indirect flag, and may be used to query the current state of the
8973 ** indirect flag for the specified session object.
8974 **
8975 ** The return value indicates the final state of the indirect flag: 0 if
8976 ** it is clear, or 1 if it is set.
8977 */
8978 
8979 /*
8980 ** CAPI3REF: Attach A Table To A Session Object
8981 **
8982 ** If argument zTab is not NULL, then it is the name of a table to attach
8983 ** to the session object passed as the first argument. All subsequent changes
8984 ** made to the table while the session object is enabled will be recorded. See
8985 ** documentation for [sqlite3session_changeset()] for further details.
8986 **
8987 ** Or, if argument zTab is NULL, then changes are recorded for all tables
8988 ** in the database. If additional tables are added to the database (by
8989 ** executing "CREATE TABLE" statements) after this call is made, changes for
8990 ** the new tables are also recorded.
8991 **
8992 ** Changes can only be recorded for tables that have a PRIMARY KEY explicitly
8993 ** defined as part of their CREATE TABLE statement. It does not matter if the
8994 ** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY
8995 ** KEY may consist of a single column, or may be a composite key.
8996 **
8997 ** It is not an error if the named table does not exist in the database. Nor
8998 ** is it an error if the named table does not have a PRIMARY KEY. However,
8999 ** no changes will be recorded in either of these scenarios.
9000 **
9001 ** Changes are not recorded for individual rows that have NULL values stored
9002 ** in one or more of their PRIMARY KEY columns.
9003 **
9004 ** SQLITE_OK is returned if the call completes without error. Or, if an error
9005 ** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned.
9006 */
9007 
9008 /* Session object */
9009 /* Table name */
9010 
9011 /*
9012 ** CAPI3REF: Set a table filter on a Session Object.
9013 **
9014 ** The second argument (xFilter) is the "filter callback". For changes to rows
9015 ** in tables that are not attached to the Session object, the filter is called
9016 ** to determine whether changes to the table's rows should be tracked or not.
9017 ** If xFilter returns 0, changes is not tracked. Note that once a table is
9018 ** attached, xFilter will not be called again.
9019 */
9020 
9021 /* Session object */
9022 
9023 /* Copy of third arg to _filter_table() */
9024 /* Table name */
9025 
9026 /* First argument passed to xFilter */
9027 
9028 /*
9029 ** CAPI3REF: Generate A Changeset From A Session Object
9030 **
9031 ** Obtain a changeset containing changes to the tables attached to the
9032 ** session object passed as the first argument. If successful,
9033 ** set *ppChangeset to point to a buffer containing the changeset
9034 ** and *pnChangeset to the size of the changeset in bytes before returning
9035 ** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to
9036 ** zero and return an SQLite error code.
9037 **
9038 ** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes,
9039 ** each representing a change to a single row of an attached table. An INSERT
9040 ** change contains the values of each field of a new database row. A DELETE
9041 ** contains the original values of each field of a deleted database row. An
9042 ** UPDATE change contains the original values of each field of an updated
9043 ** database row along with the updated values for each updated non-primary-key
9044 ** column. It is not possible for an UPDATE change to represent a change that
9045 ** modifies the values of primary key columns. If such a change is made, it
9046 ** is represented in a changeset as a DELETE followed by an INSERT.
9047 **
9048 ** Changes are not recorded for rows that have NULL values stored in one or
9049 ** more of their PRIMARY KEY columns. If such a row is inserted or deleted,
9050 ** no corresponding change is present in the changesets returned by this
9051 ** function. If an existing row with one or more NULL values stored in
9052 ** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL,
9053 ** only an INSERT is appears in the changeset. Similarly, if an existing row
9054 ** with non-NULL PRIMARY KEY values is updated so that one or more of its
9055 ** PRIMARY KEY columns are set to NULL, the resulting changeset contains a
9056 ** DELETE change only.
9057 **
9058 ** The contents of a changeset may be traversed using an iterator created
9059 ** using the [sqlite3changeset_start()] API. A changeset may be applied to
9060 ** a database with a compatible schema using the [sqlite3changeset_apply()]
9061 ** API.
9062 **
9063 ** Within a changeset generated by this function, all changes related to a
9064 ** single table are grouped together. In other words, when iterating through
9065 ** a changeset or when applying a changeset to a database, all changes related
9066 ** to a single table are processed before moving on to the next table. Tables
9067 ** are sorted in the same order in which they were attached (or auto-attached)
9068 ** to the sqlite3_session object. The order in which the changes related to
9069 ** a single table are stored is undefined.
9070 **
9071 ** Following a successful call to this function, it is the responsibility of
9072 ** the caller to eventually free the buffer that *ppChangeset points to using
9073 ** [sqlite3_free()].
9074 **
9075 ** <h3>Changeset Generation</h3>
9076 **
9077 ** Once a table has been attached to a session object, the session object
9078 ** records the primary key values of all new rows inserted into the table.
9079 ** It also records the original primary key and other column values of any
9080 ** deleted or updated rows. For each unique primary key value, data is only
9081 ** recorded once - the first time a row with said primary key is inserted,
9082 ** updated or deleted in the lifetime of the session.
9083 **
9084 ** There is one exception to the previous paragraph: when a row is inserted,
9085 ** updated or deleted, if one or more of its primary key columns contain a
9086 ** NULL value, no record of the change is made.
9087 **
9088 ** The session object therefore accumulates two types of records - those
9089 ** that consist of primary key values only (created when the user inserts
9090 ** a new record) and those that consist of the primary key values and the
9091 ** original values of other table columns (created when the users deletes
9092 ** or updates a record).
9093 **
9094 ** When this function is called, the requested changeset is created using
9095 ** both the accumulated records and the current contents of the database
9096 ** file. Specifically:
9097 **
9098 ** <ul>
9099 **   <li> For each record generated by an insert, the database is queried
9100 **        for a row with a matching primary key. If one is found, an INSERT
9101 **        change is added to the changeset. If no such row is found, no change
9102 **        is added to the changeset.
9103 **
9104 **   <li> For each record generated by an update or delete, the database is
9105 **        queried for a row with a matching primary key. If such a row is
9106 **        found and one or more of the non-primary key fields have been
9107 **        modified from their original values, an UPDATE change is added to
9108 **        the changeset. Or, if no such row is found in the table, a DELETE
9109 **        change is added to the changeset. If there is a row with a matching
9110 **        primary key in the database, but all fields contain their original
9111 **        values, no change is added to the changeset.
9112 ** </ul>
9113 **
9114 ** This means, amongst other things, that if a row is inserted and then later
9115 ** deleted while a session object is active, neither the insert nor the delete
9116 ** will be present in the changeset. Or if a row is deleted and then later a
9117 ** row with the same primary key values inserted while a session object is
9118 ** active, the resulting changeset will contain an UPDATE change instead of
9119 ** a DELETE and an INSERT.
9120 **
9121 ** When a session object is disabled (see the [sqlite3session_enable()] API),
9122 ** it does not accumulate records when rows are inserted, updated or deleted.
9123 ** This may appear to have some counter-intuitive effects if a single row
9124 ** is written to more than once during a session. For example, if a row
9125 ** is inserted while a session object is enabled, then later deleted while
9126 ** the same session object is disabled, no INSERT record will appear in the
9127 ** changeset, even though the delete took place while the session was disabled.
9128 ** Or, if one field of a row is updated while a session is disabled, and
9129 ** another field of the same row is updated while the session is enabled, the
9130 ** resulting changeset will contain an UPDATE change that updates both fields.
9131 */
9132 
9133 /* Session object */
9134 /* OUT: Size of buffer at *ppChangeset */
9135 /* OUT: Buffer containing changeset */
9136 
9137 /*
9138 ** CAPI3REF: Load The Difference Between Tables Into A Session
9139 **
9140 ** If it is not already attached to the session object passed as the first
9141 ** argument, this function attaches table zTbl in the same manner as the
9142 ** [sqlite3session_attach()] function. If zTbl does not exist, or if it
9143 ** does not have a primary key, this function is a no-op (but does not return
9144 ** an error).
9145 **
9146 ** Argument zFromDb must be the name of a database ("main", "temp" etc.)
9147 ** attached to the same database handle as the session object that contains
9148 ** a table compatible with the table attached to the session by this function.
9149 ** A table is considered compatible if it:
9150 **
9151 ** <ul>
9152 **   <li> Has the same name,
9153 **   <li> Has the same set of columns declared in the same order, and
9154 **   <li> Has the same PRIMARY KEY definition.
9155 ** </ul>
9156 **
9157 ** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables
9158 ** are compatible but do not have any PRIMARY KEY columns, it is not an error
9159 ** but no changes are added to the session object. As with other session
9160 ** APIs, tables without PRIMARY KEYs are simply ignored.
9161 **
9162 ** This function adds a set of changes to the session object that could be
9163 ** used to update the table in database zFrom (call this the "from-table")
9164 ** so that its content is the same as the table attached to the session
9165 ** object (call this the "to-table"). Specifically:
9166 **
9167 ** <ul>
9168 **   <li> For each row (primary key) that exists in the to-table but not in
9169 **     the from-table, an INSERT record is added to the session object.
9170 **
9171 **   <li> For each row (primary key) that exists in the to-table but not in
9172 **     the from-table, a DELETE record is added to the session object.
9173 **
9174 **   <li> For each row (primary key) that exists in both tables, but features
9175 **     different non-PK values in each, an UPDATE record is added to the
9176 **     session.
9177 ** </ul>
9178 **
9179 ** To clarify, if this function is called and then a changeset constructed
9180 ** using [sqlite3session_changeset()], then after applying that changeset to
9181 ** database zFrom the contents of the two compatible tables would be
9182 ** identical.
9183 **
9184 ** It an error if database zFrom does not exist or does not contain the
9185 ** required compatible table.
9186 **
9187 ** If the operation successful, SQLITE_OK is returned. Otherwise, an SQLite
9188 ** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg
9189 ** may be set to point to a buffer containing an English language error
9190 ** message. It is the responsibility of the caller to free this buffer using
9191 ** sqlite3_free().
9192 */
9193 
9194 /*
9195 ** CAPI3REF: Generate A Patchset From A Session Object
9196 **
9197 ** The differences between a patchset and a changeset are that:
9198 **
9199 ** <ul>
9200 **   <li> DELETE records consist of the primary key fields only. The
9201 **        original values of other fields are omitted.
9202 **   <li> The original values of any modified fields are omitted from
9203 **        UPDATE records.
9204 ** </ul>
9205 **
9206 ** A patchset blob may be used with up to date versions of all
9207 ** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(),
9208 ** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly,
9209 ** attempting to use a patchset blob with old versions of the
9210 ** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error.
9211 **
9212 ** Because the non-primary key "old.*" fields are omitted, no
9213 ** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset
9214 ** is passed to the sqlite3changeset_apply() API. Other conflict types work
9215 ** in the same way as for changesets.
9216 **
9217 ** Changes within a patchset are ordered in the same way as for changesets
9218 ** generated by the sqlite3session_changeset() function (i.e. all changes for
9219 ** a single table are grouped together, tables appear in the order in which
9220 ** they were attached to the session object).
9221 */
9222 
9223 /* Session object */
9224 /* OUT: Size of buffer at *ppPatchset */
9225 /* OUT: Buffer containing patchset */
9226 
9227 /*
9228 ** CAPI3REF: Test if a changeset has recorded any changes.
9229 **
9230 ** Return non-zero if no changes to attached tables have been recorded by
9231 ** the session object passed as the first argument. Otherwise, if one or
9232 ** more changes have been recorded, return zero.
9233 **
9234 ** Even if this function returns zero, it is possible that calling
9235 ** [sqlite3session_changeset()] on the session handle may still return a
9236 ** changeset that contains no changes. This can happen when a row in
9237 ** an attached table is modified and then later on the original values
9238 ** are restored. However, if this function returns non-zero, then it is
9239 ** guaranteed that a call to sqlite3session_changeset() will return a
9240 ** changeset containing zero changes.
9241 */
9242 
9243 /*
9244 ** CAPI3REF: Create An Iterator To Traverse A Changeset
9245 **
9246 ** Create an iterator used to iterate through the contents of a changeset.
9247 ** If successful, *pp is set to point to the iterator handle and SQLITE_OK
9248 ** is returned. Otherwise, if an error occurs, *pp is set to zero and an
9249 ** SQLite error code is returned.
9250 **
9251 ** The following functions can be used to advance and query a changeset
9252 ** iterator created by this function:
9253 **
9254 ** <ul>
9255 **   <li> [sqlite3changeset_next()]
9256 **   <li> [sqlite3changeset_op()]
9257 **   <li> [sqlite3changeset_new()]
9258 **   <li> [sqlite3changeset_old()]
9259 ** </ul>
9260 **
9261 ** It is the responsibility of the caller to eventually destroy the iterator
9262 ** by passing it to [sqlite3changeset_finalize()]. The buffer containing the
9263 ** changeset (pChangeset) must remain valid until after the iterator is
9264 ** destroyed.
9265 **
9266 ** Assuming the changeset blob was created by one of the
9267 ** [sqlite3session_changeset()], [sqlite3changeset_concat()] or
9268 ** [sqlite3changeset_invert()] functions, all changes within the changeset
9269 ** that apply to a single table are grouped together. This means that when
9270 ** an application iterates through a changeset using an iterator created by
9271 ** this function, all changes that relate to a single table are visited
9272 ** consecutively. There is no chance that the iterator will visit a change
9273 ** the applies to table X, then one for table Y, and then later on visit
9274 ** another change for table X.
9275 */
9276 
9277 /* OUT: New changeset iterator handle */
9278 /* Size of changeset blob in bytes */
9279 /* Pointer to blob containing changeset */
9280 
9281 /*
9282 ** CAPI3REF: Advance A Changeset Iterator
9283 **
9284 ** This function may only be used with iterators created by function
9285 ** [sqlite3changeset_start()]. If it is called on an iterator passed to
9286 ** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE
9287 ** is returned and the call has no effect.
9288 **
9289 ** Immediately after an iterator is created by sqlite3changeset_start(), it
9290 ** does not point to any change in the changeset. Assuming the changeset
9291 ** is not empty, the first call to this function advances the iterator to
9292 ** point to the first change in the changeset. Each subsequent call advances
9293 ** the iterator to point to the next change in the changeset (if any). If
9294 ** no error occurs and the iterator points to a valid change after a call
9295 ** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned.
9296 ** Otherwise, if all changes in the changeset have already been visited,
9297 ** SQLITE_DONE is returned.
9298 **
9299 ** If an error occurs, an SQLite error code is returned. Possible error
9300 ** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or
9301 ** SQLITE_NOMEM.
9302 */
9303 
9304 /*
9305 ** CAPI3REF: Obtain The Current Operation From A Changeset Iterator
9306 **
9307 ** The pIter argument passed to this function may either be an iterator
9308 ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
9309 ** created by [sqlite3changeset_start()]. In the latter case, the most recent
9310 ** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this
9311 ** is not the case, this function returns [SQLITE_MISUSE].
9312 **
9313 ** If argument pzTab is not NULL, then *pzTab is set to point to a
9314 ** nul-terminated utf-8 encoded string containing the name of the table
9315 ** affected by the current change. The buffer remains valid until either
9316 ** sqlite3changeset_next() is called on the iterator or until the
9317 ** conflict-handler function returns. If pnCol is not NULL, then *pnCol is
9318 ** set to the number of columns in the table affected by the change. If
9319 ** pbIncorrect is not NULL, then *pbIndirect is set to true (1) if the change
9320 ** is an indirect change, or false (0) otherwise. See the documentation for
9321 ** [sqlite3session_indirect()] for a description of direct and indirect
9322 ** changes. Finally, if pOp is not NULL, then *pOp is set to one of
9323 ** [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], depending on the
9324 ** type of change that the iterator currently points to.
9325 **
9326 ** If no error occurs, SQLITE_OK is returned. If an error does occur, an
9327 ** SQLite error code is returned. The values of the output variables may not
9328 ** be trusted in this case.
9329 */
9330 
9331 /* Iterator object */
9332 /* OUT: Pointer to table name */
9333 /* OUT: Number of columns in table */
9334 /* OUT: SQLITE_INSERT, DELETE or UPDATE */
9335 /* OUT: True for an 'indirect' change */
9336 
9337 /*
9338 ** CAPI3REF: Obtain The Primary Key Definition Of A Table
9339 **
9340 ** For each modified table, a changeset includes the following:
9341 **
9342 ** <ul>
9343 **   <li> The number of columns in the table, and
9344 **   <li> Which of those columns make up the tables PRIMARY KEY.
9345 ** </ul>
9346 **
9347 ** This function is used to find which columns comprise the PRIMARY KEY of
9348 ** the table modified by the change that iterator pIter currently points to.
9349 ** If successful, *pabPK is set to point to an array of nCol entries, where
9350 ** nCol is the number of columns in the table. Elements of *pabPK are set to
9351 ** 0x01 if the corresponding column is part of the tables primary key, or
9352 ** 0x00 if it is not.
9353 **
9354 ** If argument pnCol is not NULL, then *pnCol is set to the number of columns
9355 ** in the table.
9356 **
9357 ** If this function is called when the iterator does not point to a valid
9358 ** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise,
9359 ** SQLITE_OK is returned and the output variables populated as described
9360 ** above.
9361 */
9362 
9363 /* Iterator object */
9364 /* OUT: Array of boolean - true for PK cols */
9365 /* OUT: Number of entries in output array */
9366 
9367 /*
9368 ** CAPI3REF: Obtain old.* Values From A Changeset Iterator
9369 **
9370 ** The pIter argument passed to this function may either be an iterator
9371 ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
9372 ** created by [sqlite3changeset_start()]. In the latter case, the most recent
9373 ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
9374 ** Furthermore, it may only be called if the type of change that the iterator
9375 ** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise,
9376 ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
9377 **
9378 ** Argument iVal must be greater than or equal to 0, and less than the number
9379 ** of columns in the table affected by the current change. Otherwise,
9380 ** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
9381 **
9382 ** If successful, this function sets *ppValue to point to a protected
9383 ** sqlite3_value object containing the iVal'th value from the vector of
9384 ** original row values stored as part of the UPDATE or DELETE change and
9385 ** returns SQLITE_OK. The name of the function comes from the fact that this
9386 ** is similar to the "old.*" columns available to update or delete triggers.
9387 **
9388 ** If some other error occurs (e.g. an OOM condition), an SQLite error code
9389 ** is returned and *ppValue is set to NULL.
9390 */
9391 
9392 /* Changeset iterator */
9393 /* Column number */
9394 /* OUT: Old value (or NULL pointer) */
9395 
9396 /*
9397 ** CAPI3REF: Obtain new.* Values From A Changeset Iterator
9398 **
9399 ** The pIter argument passed to this function may either be an iterator
9400 ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
9401 ** created by [sqlite3changeset_start()]. In the latter case, the most recent
9402 ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
9403 ** Furthermore, it may only be called if the type of change that the iterator
9404 ** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise,
9405 ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
9406 **
9407 ** Argument iVal must be greater than or equal to 0, and less than the number
9408 ** of columns in the table affected by the current change. Otherwise,
9409 ** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
9410 **
9411 ** If successful, this function sets *ppValue to point to a protected
9412 ** sqlite3_value object containing the iVal'th value from the vector of
9413 ** new row values stored as part of the UPDATE or INSERT change and
9414 ** returns SQLITE_OK. If the change is an UPDATE and does not include
9415 ** a new value for the requested column, *ppValue is set to NULL and
9416 ** SQLITE_OK returned. The name of the function comes from the fact that
9417 ** this is similar to the "new.*" columns available to update or delete
9418 ** triggers.
9419 **
9420 ** If some other error occurs (e.g. an OOM condition), an SQLite error code
9421 ** is returned and *ppValue is set to NULL.
9422 */
9423 
9424 /* Changeset iterator */
9425 /* Column number */
9426 /* OUT: New value (or NULL pointer) */
9427 
9428 /*
9429 ** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator
9430 **
9431 ** This function should only be used with iterator objects passed to a
9432 ** conflict-handler callback by [sqlite3changeset_apply()] with either
9433 ** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function
9434 ** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue
9435 ** is set to NULL.
9436 **
9437 ** Argument iVal must be greater than or equal to 0, and less than the number
9438 ** of columns in the table affected by the current change. Otherwise,
9439 ** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
9440 **
9441 ** If successful, this function sets *ppValue to point to a protected
9442 ** sqlite3_value object containing the iVal'th value from the
9443 ** "conflicting row" associated with the current conflict-handler callback
9444 ** and returns SQLITE_OK.
9445 **
9446 ** If some other error occurs (e.g. an OOM condition), an SQLite error code
9447 ** is returned and *ppValue is set to NULL.
9448 */
9449 
9450 /* Changeset iterator */
9451 /* Column number */
9452 /* OUT: Value from conflicting row */
9453 
9454 /*
9455 ** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations
9456 **
9457 ** This function may only be called with an iterator passed to an
9458 ** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case
9459 ** it sets the output variable to the total number of known foreign key
9460 ** violations in the destination database and returns SQLITE_OK.
9461 **
9462 ** In all other cases this function returns SQLITE_MISUSE.
9463 */
9464 
9465 /* Changeset iterator */
9466 /* OUT: Number of FK violations */
9467 
9468 /*
9469 ** CAPI3REF: Finalize A Changeset Iterator
9470 **
9471 ** This function is used to finalize an iterator allocated with
9472 ** [sqlite3changeset_start()].
9473 **
9474 ** This function should only be called on iterators created using the
9475 ** [sqlite3changeset_start()] function. If an application calls this
9476 ** function with an iterator passed to a conflict-handler by
9477 ** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the
9478 ** call has no effect.
9479 **
9480 ** If an error was encountered within a call to an sqlite3changeset_xxx()
9481 ** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an
9482 ** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding
9483 ** to that error is returned by this function. Otherwise, SQLITE_OK is
9484 ** returned. This is to allow the following pattern (pseudo-code):
9485 **
9486 **   sqlite3changeset_start();
9487 **   while( SQLITE_ROW==sqlite3changeset_next() ){
9488 **     // Do something with change.
9489 **   }
9490 **   rc = sqlite3changeset_finalize();
9491 **   if( rc!=SQLITE_OK ){
9492 **     // An error has occurred
9493 **   }
9494 */
9495 
9496 /*
9497 ** CAPI3REF: Invert A Changeset
9498 **
9499 ** This function is used to "invert" a changeset object. Applying an inverted
9500 ** changeset to a database reverses the effects of applying the uninverted
9501 ** changeset. Specifically:
9502 **
9503 ** <ul>
9504 **   <li> Each DELETE change is changed to an INSERT, and
9505 **   <li> Each INSERT change is changed to a DELETE, and
9506 **   <li> For each UPDATE change, the old.* and new.* values are exchanged.
9507 ** </ul>
9508 **
9509 ** This function does not change the order in which changes appear within
9510 ** the changeset. It merely reverses the sense of each individual change.
9511 **
9512 ** If successful, a pointer to a buffer containing the inverted changeset
9513 ** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and
9514 ** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are
9515 ** zeroed and an SQLite error code returned.
9516 **
9517 ** It is the responsibility of the caller to eventually call sqlite3_free()
9518 ** on the *ppOut pointer to free the buffer allocation following a successful
9519 ** call to this function.
9520 **
9521 ** WARNING/TODO: This function currently assumes that the input is a valid
9522 ** changeset. If it is not, the results are undefined.
9523 */
9524 
9525 /* Input changeset */
9526 /* OUT: Inverse of input */
9527 
9528 /*
9529 ** CAPI3REF: Concatenate Two Changeset Objects
9530 **
9531 ** This function is used to concatenate two changesets, A and B, into a
9532 ** single changeset. The result is a changeset equivalent to applying
9533 ** changeset A followed by changeset B.
9534 **
9535 ** This function combines the two input changesets using an
9536 ** sqlite3_changegroup object. Calling it produces similar results as the
9537 ** following code fragment:
9538 **
9539 **   sqlite3_changegroup *pGrp;
9540 **   rc = sqlite3_changegroup_new(&pGrp);
9541 **   if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA);
9542 **   if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB);
9543 **   if( rc==SQLITE_OK ){
9544 **     rc = sqlite3changegroup_output(pGrp, pnOut, ppOut);
9545 **   }else{
9546 **     *ppOut = 0;
9547 **     *pnOut = 0;
9548 **   }
9549 **
9550 ** Refer to the sqlite3_changegroup documentation below for details.
9551 */
9552 
9553 /* Number of bytes in buffer pA */
9554 /* Pointer to buffer containing changeset A */
9555 /* Number of bytes in buffer pB */
9556 /* Pointer to buffer containing changeset B */
9557 /* OUT: Number of bytes in output changeset */
9558 /* OUT: Buffer containing output changeset */
9559 
9560 /*
9561 ** CAPI3REF: Changegroup Handle
9562 */
9563 
9564 /*
9565 ** CAPI3REF: Create A New Changegroup Object
9566 **
9567 ** An sqlite3_changegroup object is used to combine two or more changesets
9568 ** (or patchsets) into a single changeset (or patchset). A single changegroup
9569 ** object may combine changesets or patchsets, but not both. The output is
9570 ** always in the same format as the input.
9571 **
9572 ** If successful, this function returns SQLITE_OK and populates (*pp) with
9573 ** a pointer to a new sqlite3_changegroup object before returning. The caller
9574 ** should eventually free the returned object using a call to
9575 ** sqlite3changegroup_delete(). If an error occurs, an SQLite error code
9576 ** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL.
9577 **
9578 ** The usual usage pattern for an sqlite3_changegroup object is as follows:
9579 **
9580 ** <ul>
9581 **   <li> It is created using a call to sqlite3changegroup_new().
9582 **
9583 **   <li> Zero or more changesets (or patchsets) are added to the object
9584 **        by calling sqlite3changegroup_add().
9585 **
9586 **   <li> The result of combining all input changesets together is obtained
9587 **        by the application via a call to sqlite3changegroup_output().
9588 **
9589 **   <li> The object is deleted using a call to sqlite3changegroup_delete().
9590 ** </ul>
9591 **
9592 ** Any number of calls to add() and output() may be made between the calls to
9593 ** new() and delete(), and in any order.
9594 **
9595 ** As well as the regular sqlite3changegroup_add() and
9596 ** sqlite3changegroup_output() functions, also available are the streaming
9597 ** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm().
9598 */
9599 
9600 /*
9601 ** CAPI3REF: Add A Changeset To A Changegroup
9602 **
9603 ** Add all changes within the changeset (or patchset) in buffer pData (size
9604 ** nData bytes) to the changegroup.
9605 **
9606 ** If the buffer contains a patchset, then all prior calls to this function
9607 ** on the same changegroup object must also have specified patchsets. Or, if
9608 ** the buffer contains a changeset, so must have the earlier calls to this
9609 ** function. Otherwise, SQLITE_ERROR is returned and no changes are added
9610 ** to the changegroup.
9611 **
9612 ** Rows within the changeset and changegroup are identified by the values in
9613 ** their PRIMARY KEY columns. A change in the changeset is considered to
9614 ** apply to the same row as a change already present in the changegroup if
9615 ** the two rows have the same primary key.
9616 **
9617 ** Changes to rows that do not already appear in the changegroup are
9618 ** simply copied into it. Or, if both the new changeset and the changegroup
9619 ** contain changes that apply to a single row, the final contents of the
9620 ** changegroup depends on the type of each change, as follows:
9621 **
9622 ** <table border=1 style="margin-left:8ex;margin-right:8ex">
9623 **   <tr><th style="white-space:pre">Existing Change  </th>
9624 **       <th style="white-space:pre">New Change       </th>
9625 **       <th>Output Change
9626 **   <tr><td>INSERT <td>INSERT <td>
9627 **       The new change is ignored. This case does not occur if the new
9628 **       changeset was recorded immediately after the changesets already
9629 **       added to the changegroup.
9630 **   <tr><td>INSERT <td>UPDATE <td>
9631 **       The INSERT change remains in the changegroup. The values in the
9632 **       INSERT change are modified as if the row was inserted by the
9633 **       existing change and then updated according to the new change.
9634 **   <tr><td>INSERT <td>DELETE <td>
9635 **       The existing INSERT is removed from the changegroup. The DELETE is
9636 **       not added.
9637 **   <tr><td>UPDATE <td>INSERT <td>
9638 **       The new change is ignored. This case does not occur if the new
9639 **       changeset was recorded immediately after the changesets already
9640 **       added to the changegroup.
9641 **   <tr><td>UPDATE <td>UPDATE <td>
9642 **       The existing UPDATE remains within the changegroup. It is amended
9643 **       so that the accompanying values are as if the row was updated once
9644 **       by the existing change and then again by the new change.
9645 **   <tr><td>UPDATE <td>DELETE <td>
9646 **       The existing UPDATE is replaced by the new DELETE within the
9647 **       changegroup.
9648 **   <tr><td>DELETE <td>INSERT <td>
9649 **       If one or more of the column values in the row inserted by the
9650 **       new change differ from those in the row deleted by the existing
9651 **       change, the existing DELETE is replaced by an UPDATE within the
9652 **       changegroup. Otherwise, if the inserted row is exactly the same
9653 **       as the deleted row, the existing DELETE is simply discarded.
9654 **   <tr><td>DELETE <td>UPDATE <td>
9655 **       The new change is ignored. This case does not occur if the new
9656 **       changeset was recorded immediately after the changesets already
9657 **       added to the changegroup.
9658 **   <tr><td>DELETE <td>DELETE <td>
9659 **       The new change is ignored. This case does not occur if the new
9660 **       changeset was recorded immediately after the changesets already
9661 **       added to the changegroup.
9662 ** </table>
9663 **
9664 ** If the new changeset contains changes to a table that is already present
9665 ** in the changegroup, then the number of columns and the position of the
9666 ** primary key columns for the table must be consistent. If this is not the
9667 ** case, this function fails with SQLITE_SCHEMA. If the input changeset
9668 ** appears to be corrupt and the corruption is detected, SQLITE_CORRUPT is
9669 ** returned. Or, if an out-of-memory condition occurs during processing, this
9670 ** function returns SQLITE_NOMEM. In all cases, if an error occurs the
9671 ** final contents of the changegroup is undefined.
9672 **
9673 ** If no error occurs, SQLITE_OK is returned.
9674 */
9675 
9676 /*
9677 ** CAPI3REF: Obtain A Composite Changeset From A Changegroup
9678 **
9679 ** Obtain a buffer containing a changeset (or patchset) representing the
9680 ** current contents of the changegroup. If the inputs to the changegroup
9681 ** were themselves changesets, the output is a changeset. Or, if the
9682 ** inputs were patchsets, the output is also a patchset.
9683 **
9684 ** As with the output of the sqlite3session_changeset() and
9685 ** sqlite3session_patchset() functions, all changes related to a single
9686 ** table are grouped together in the output of this function. Tables appear
9687 ** in the same order as for the very first changeset added to the changegroup.
9688 ** If the second or subsequent changesets added to the changegroup contain
9689 ** changes for tables that do not appear in the first changeset, they are
9690 ** appended onto the end of the output changeset, again in the order in
9691 ** which they are first encountered.
9692 **
9693 ** If an error occurs, an SQLite error code is returned and the output
9694 ** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK
9695 ** is returned and the output variables are set to the size of and a
9696 ** pointer to the output buffer, respectively. In this case it is the
9697 ** responsibility of the caller to eventually free the buffer using a
9698 ** call to sqlite3_free().
9699 */
9700 
9701 /* OUT: Size of output buffer in bytes */
9702 /* OUT: Pointer to output buffer */
9703 
9704 /*
9705 ** CAPI3REF: Delete A Changegroup Object
9706 */
9707 
9708 /*
9709 ** CAPI3REF: Apply A Changeset To A Database
9710 **
9711 ** Apply a changeset to a database. This function attempts to update the
9712 ** "main" database attached to handle db with the changes found in the
9713 ** changeset passed via the second and third arguments.
9714 **
9715 ** The fourth argument (xFilter) passed to this function is the "filter
9716 ** callback". If it is not NULL, then for each table affected by at least one
9717 ** change in the changeset, the filter callback is invoked with
9718 ** the table name as the second argument, and a copy of the context pointer
9719 ** passed as the sixth argument to this function as the first. If the "filter
9720 ** callback" returns zero, then no attempt is made to apply any changes to
9721 ** the table. Otherwise, if the return value is non-zero or the xFilter
9722 ** argument to this function is NULL, all changes related to the table are
9723 ** attempted.
9724 **
9725 ** For each table that is not excluded by the filter callback, this function
9726 ** tests that the target database contains a compatible table. A table is
9727 ** considered compatible if all of the following are true:
9728 **
9729 ** <ul>
9730 **   <li> The table has the same name as the name recorded in the
9731 **        changeset, and
9732 **   <li> The table has at least as many columns as recorded in the
9733 **        changeset, and
9734 **   <li> The table has primary key columns in the same position as
9735 **        recorded in the changeset.
9736 ** </ul>
9737 **
9738 ** If there is no compatible table, it is not an error, but none of the
9739 ** changes associated with the table are applied. A warning message is issued
9740 ** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most
9741 ** one such warning is issued for each table in the changeset.
9742 **
9743 ** For each change for which there is a compatible table, an attempt is made
9744 ** to modify the table contents according to the UPDATE, INSERT or DELETE
9745 ** change. If a change cannot be applied cleanly, the conflict handler
9746 ** function passed as the fifth argument to sqlite3changeset_apply() may be
9747 ** invoked. A description of exactly when the conflict handler is invoked for
9748 ** each type of change is below.
9749 **
9750 ** Unlike the xFilter argument, xConflict may not be passed NULL. The results
9751 ** of passing anything other than a valid function pointer as the xConflict
9752 ** argument are undefined.
9753 **
9754 ** Each time the conflict handler function is invoked, it must return one
9755 ** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or
9756 ** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned
9757 ** if the second argument passed to the conflict handler is either
9758 ** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler
9759 ** returns an illegal value, any changes already made are rolled back and
9760 ** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different
9761 ** actions are taken by sqlite3changeset_apply() depending on the value
9762 ** returned by each invocation of the conflict-handler function. Refer to
9763 ** the documentation for the three
9764 ** [SQLITE_CHANGESET_OMIT|available return values] for details.
9765 **
9766 ** <dl>
9767 ** <dt>DELETE Changes<dd>
9768 **   For each DELETE change, this function checks if the target database
9769 **   contains a row with the same primary key value (or values) as the
9770 **   original row values stored in the changeset. If it does, and the values
9771 **   stored in all non-primary key columns also match the values stored in
9772 **   the changeset the row is deleted from the target database.
9773 **
9774 **   If a row with matching primary key values is found, but one or more of
9775 **   the non-primary key fields contains a value different from the original
9776 **   row value stored in the changeset, the conflict-handler function is
9777 **   invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the
9778 **   database table has more columns than are recorded in the changeset,
9779 **   only the values of those non-primary key fields are compared against
9780 **   the current database contents - any trailing database table columns
9781 **   are ignored.
9782 **
9783 **   If no row with matching primary key values is found in the database,
9784 **   the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
9785 **   passed as the second argument.
9786 **
9787 **   If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT
9788 **   (which can only happen if a foreign key constraint is violated), the
9789 **   conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT]
9790 **   passed as the second argument. This includes the case where the DELETE
9791 **   operation is attempted because an earlier call to the conflict handler
9792 **   function returned [SQLITE_CHANGESET_REPLACE].
9793 **
9794 ** <dt>INSERT Changes<dd>
9795 **   For each INSERT change, an attempt is made to insert the new row into
9796 **   the database. If the changeset row contains fewer fields than the
9797 **   database table, the trailing fields are populated with their default
9798 **   values.
9799 **
9800 **   If the attempt to insert the row fails because the database already
9801 **   contains a row with the same primary key values, the conflict handler
9802 **   function is invoked with the second argument set to
9803 **   [SQLITE_CHANGESET_CONFLICT].
9804 **
9805 **   If the attempt to insert the row fails because of some other constraint
9806 **   violation (e.g. NOT NULL or UNIQUE), the conflict handler function is
9807 **   invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT].
9808 **   This includes the case where the INSERT operation is re-attempted because
9809 **   an earlier call to the conflict handler function returned
9810 **   [SQLITE_CHANGESET_REPLACE].
9811 **
9812 ** <dt>UPDATE Changes<dd>
9813 **   For each UPDATE change, this function checks if the target database
9814 **   contains a row with the same primary key value (or values) as the
9815 **   original row values stored in the changeset. If it does, and the values
9816 **   stored in all modified non-primary key columns also match the values
9817 **   stored in the changeset the row is updated within the target database.
9818 **
9819 **   If a row with matching primary key values is found, but one or more of
9820 **   the modified non-primary key fields contains a value different from an
9821 **   original row value stored in the changeset, the conflict-handler function
9822 **   is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since
9823 **   UPDATE changes only contain values for non-primary key fields that are
9824 **   to be modified, only those fields need to match the original values to
9825 **   avoid the SQLITE_CHANGESET_DATA conflict-handler callback.
9826 **
9827 **   If no row with matching primary key values is found in the database,
9828 **   the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
9829 **   passed as the second argument.
9830 **
9831 **   If the UPDATE operation is attempted, but SQLite returns
9832 **   SQLITE_CONSTRAINT, the conflict-handler function is invoked with
9833 **   [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument.
9834 **   This includes the case where the UPDATE operation is attempted after
9835 **   an earlier call to the conflict handler function returned
9836 **   [SQLITE_CHANGESET_REPLACE].
9837 ** </dl>
9838 **
9839 ** It is safe to execute SQL statements, including those that write to the
9840 ** table that the callback related to, from within the xConflict callback.
9841 ** This can be used to further customize the applications conflict
9842 ** resolution strategy.
9843 **
9844 ** All changes made by this function are enclosed in a savepoint transaction.
9845 ** If any other error (aside from a constraint failure when attempting to
9846 ** write to the target database) occurs, then the savepoint transaction is
9847 ** rolled back, restoring the target database to its original state, and an
9848 ** SQLite error code returned.
9849 */
9850 
9851 /* Apply change to "main" db of this handle */
9852 /* Size of changeset in bytes */
9853 /* Changeset blob */
9854 
9855 /* Copy of sixth arg to _apply() */
9856 /* Table name */
9857 
9858 /* Copy of sixth arg to _apply() */
9859 /* DATA, MISSING, CONFLICT, CONSTRAINT */
9860 /* Handle describing change and conflict */
9861 
9862 /* First argument passed to xConflict */
9863 
9864 /*
9865 ** CAPI3REF: Constants Passed To The Conflict Handler
9866 **
9867 ** Values that may be passed as the second argument to a conflict-handler.
9868 **
9869 ** <dl>
9870 ** <dt>SQLITE_CHANGESET_DATA<dd>
9871 **   The conflict handler is invoked with CHANGESET_DATA as the second argument
9872 **   when processing a DELETE or UPDATE change if a row with the required
9873 **   PRIMARY KEY fields is present in the database, but one or more other
9874 **   (non primary-key) fields modified by the update do not contain the
9875 **   expected "before" values.
9876 **
9877 **   The conflicting row, in this case, is the database row with the matching
9878 **   primary key.
9879 **
9880 ** <dt>SQLITE_CHANGESET_NOTFOUND<dd>
9881 **   The conflict handler is invoked with CHANGESET_NOTFOUND as the second
9882 **   argument when processing a DELETE or UPDATE change if a row with the
9883 **   required PRIMARY KEY fields is not present in the database.
9884 **
9885 **   There is no conflicting row in this case. The results of invoking the
9886 **   sqlite3changeset_conflict() API are undefined.
9887 **
9888 ** <dt>SQLITE_CHANGESET_CONFLICT<dd>
9889 **   CHANGESET_CONFLICT is passed as the second argument to the conflict
9890 **   handler while processing an INSERT change if the operation would result
9891 **   in duplicate primary key values.
9892 **
9893 **   The conflicting row in this case is the database row with the matching
9894 **   primary key.
9895 **
9896 ** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd>
9897 **   If foreign key handling is enabled, and applying a changeset leaves the
9898 **   database in a state containing foreign key violations, the conflict
9899 **   handler is invoked with CHANGESET_FOREIGN_KEY as the second argument
9900 **   exactly once before the changeset is committed. If the conflict handler
9901 **   returns CHANGESET_OMIT, the changes, including those that caused the
9902 **   foreign key constraint violation, are committed. Or, if it returns
9903 **   CHANGESET_ABORT, the changeset is rolled back.
9904 **
9905 **   No current or conflicting row information is provided. The only function
9906 **   it is possible to call on the supplied sqlite3_changeset_iter handle
9907 **   is sqlite3changeset_fk_conflicts().
9908 **
9909 ** <dt>SQLITE_CHANGESET_CONSTRAINT<dd>
9910 **   If any other constraint violation occurs while applying a change (i.e.
9911 **   a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is
9912 **   invoked with CHANGESET_CONSTRAINT as the second argument.
9913 **
9914 **   There is no conflicting row in this case. The results of invoking the
9915 **   sqlite3changeset_conflict() API are undefined.
9916 **
9917 ** </dl>
9918 */
9919 
9920 /*
9921 ** CAPI3REF: Constants Returned By The Conflict Handler
9922 **
9923 ** A conflict handler callback must return one of the following three values.
9924 **
9925 ** <dl>
9926 ** <dt>SQLITE_CHANGESET_OMIT<dd>
9927 **   If a conflict handler returns this value no special action is taken. The
9928 **   change that caused the conflict is not applied. The session module
9929 **   continues to the next change in the changeset.
9930 **
9931 ** <dt>SQLITE_CHANGESET_REPLACE<dd>
9932 **   This value may only be returned if the second argument to the conflict
9933 **   handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this
9934 **   is not the case, any changes applied so far are rolled back and the
9935 **   call to sqlite3changeset_apply() returns SQLITE_MISUSE.
9936 **
9937 **   If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict
9938 **   handler, then the conflicting row is either updated or deleted, depending
9939 **   on the type of change.
9940 **
9941 **   If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict
9942 **   handler, then the conflicting row is removed from the database and a
9943 **   second attempt to apply the change is made. If this second attempt fails,
9944 **   the original row is restored to the database before continuing.
9945 **
9946 ** <dt>SQLITE_CHANGESET_ABORT<dd>
9947 **   If this value is returned, any changes applied so far are rolled back
9948 **   and the call to sqlite3changeset_apply() returns SQLITE_ABORT.
9949 ** </dl>
9950 */
9951 
9952 /*
9953 ** CAPI3REF: Streaming Versions of API functions.
9954 **
9955 ** The six streaming API xxx_strm() functions serve similar purposes to the
9956 ** corresponding non-streaming API functions:
9957 **
9958 ** <table border=1 style="margin-left:8ex;margin-right:8ex">
9959 **   <tr><th>Streaming function<th>Non-streaming equivalent</th>
9960 **   <tr><td>sqlite3changeset_apply_strm<td>[sqlite3changeset_apply]
9961 **   <tr><td>sqlite3changeset_concat_strm<td>[sqlite3changeset_concat]
9962 **   <tr><td>sqlite3changeset_invert_strm<td>[sqlite3changeset_invert]
9963 **   <tr><td>sqlite3changeset_start_strm<td>[sqlite3changeset_start]
9964 **   <tr><td>sqlite3session_changeset_strm<td>[sqlite3session_changeset]
9965 **   <tr><td>sqlite3session_patchset_strm<td>[sqlite3session_patchset]
9966 ** </table>
9967 **
9968 ** Non-streaming functions that accept changesets (or patchsets) as input
9969 ** require that the entire changeset be stored in a single buffer in memory.
9970 ** Similarly, those that return a changeset or patchset do so by returning
9971 ** a pointer to a single large buffer allocated using sqlite3_malloc().
9972 ** Normally this is convenient. However, if an application running in a
9973 ** low-memory environment is required to handle very large changesets, the
9974 ** large contiguous memory allocations required can become onerous.
9975 **
9976 ** In order to avoid this problem, instead of a single large buffer, input
9977 ** is passed to a streaming API functions by way of a callback function that
9978 ** the sessions module invokes to incrementally request input data as it is
9979 ** required. In all cases, a pair of API function parameters such as
9980 **
9981 **  <pre>
9982 **  &nbsp;     int nChangeset,
9983 **  &nbsp;     void *pChangeset,
9984 **  </pre>
9985 **
9986 ** Is replaced by:
9987 **
9988 **  <pre>
9989 **  &nbsp;     int (*xInput)(void *pIn, void *pData, int *pnData),
9990 **  &nbsp;     void *pIn,
9991 **  </pre>
9992 **
9993 ** Each time the xInput callback is invoked by the sessions module, the first
9994 ** argument passed is a copy of the supplied pIn context pointer. The second
9995 ** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no
9996 ** error occurs the xInput method should copy up to (*pnData) bytes of data
9997 ** into the buffer and set (*pnData) to the actual number of bytes copied
9998 ** before returning SQLITE_OK. If the input is completely exhausted, (*pnData)
9999 ** should be set to zero to indicate this. Or, if an error occurs, an SQLite
10000 ** error code should be returned. In all cases, if an xInput callback returns
10001 ** an error, all processing is abandoned and the streaming API function
10002 ** returns a copy of the error code to the caller.
10003 **
10004 ** In the case of sqlite3changeset_start_strm(), the xInput callback may be
10005 ** invoked by the sessions module at any point during the lifetime of the
10006 ** iterator. If such an xInput callback returns an error, the iterator enters
10007 ** an error state, whereby all subsequent calls to iterator functions
10008 ** immediately fail with the same error code as returned by xInput.
10009 **
10010 ** Similarly, streaming API functions that return changesets (or patchsets)
10011 ** return them in chunks by way of a callback function instead of via a
10012 ** pointer to a single large buffer. In this case, a pair of parameters such
10013 ** as:
10014 **
10015 **  <pre>
10016 **  &nbsp;     int *pnChangeset,
10017 **  &nbsp;     void **ppChangeset,
10018 **  </pre>
10019 **
10020 ** Is replaced by:
10021 **
10022 **  <pre>
10023 **  &nbsp;     int (*xOutput)(void *pOut, const void *pData, int nData),
10024 **  &nbsp;     void *pOut
10025 **  </pre>
10026 **
10027 ** The xOutput callback is invoked zero or more times to return data to
10028 ** the application. The first parameter passed to each call is a copy of the
10029 ** pOut pointer supplied by the application. The second parameter, pData,
10030 ** points to a buffer nData bytes in size containing the chunk of output
10031 ** data being returned. If the xOutput callback successfully processes the
10032 ** supplied data, it should return SQLITE_OK to indicate success. Otherwise,
10033 ** it should return some other SQLite error code. In this case processing
10034 ** is immediately abandoned and the streaming API function returns a copy
10035 ** of the xOutput error code to the application.
10036 **
10037 ** The sessions module never invokes an xOutput callback with the third
10038 ** parameter set to a value less than or equal to zero. Other than this,
10039 ** no guarantees are made as to the size of the chunks of data returned.
10040 */
10041 
10042 /* Apply change to "main" db of this handle */
10043 /* Input function */
10044 /* First arg for xInput */
10045 
10046 /* Copy of sixth arg to _apply() */
10047 /* Table name */
10048 
10049 /* Copy of sixth arg to _apply() */
10050 /* DATA, MISSING, CONFLICT, CONSTRAINT */
10051 /* Handle describing change and conflict */
10052 
10053 /* First argument passed to xConflict */
10054 
10055 /*
10056 ** Make sure we can call this stuff from C++.
10057 */
10058 
10059 /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */
10060 
10061 /******** End of sqlite3session.h *********/
10062 /******** Begin file fts5.h *********/
10063 /*
10064 ** 2014 May 31
10065 **
10066 ** The author disclaims copyright to this source code.  In place of
10067 ** a legal notice, here is a blessing:
10068 **
10069 **    May you do good and not evil.
10070 **    May you find forgiveness for yourself and forgive others.
10071 **    May you share freely, never taking more than you give.
10072 **
10073 ******************************************************************************
10074 **
10075 ** Interfaces to extend FTS5. Using the interfaces defined in this file,
10076 ** FTS5 may be extended with:
10077 **
10078 **     * custom tokenizers, and
10079 **     * custom auxiliary functions.
10080 */
10081 
10082 /*************************************************************************
10083 ** CUSTOM AUXILIARY FUNCTIONS
10084 **
10085 ** Virtual table implementations may overload SQL functions by implementing
10086 ** the sqlite3_module.xFindFunction() method.
10087 */
10088 
10089 struct Fts5Context;
10090 
10091 /* API offered by current FTS version */
10092 /* First arg to pass to pApi functions */
10093 /* Context for returning result/error */
10094 /* Number of values in apVal[] array */
10095 /* Array of trailing arguments */
10096 alias fts5_extension_function = void function(const(Fts5ExtensionApi)* pApi, Fts5Context* pFts, sqlite3_context* pCtx, int nVal, sqlite3_value** apVal);
10097 
10098 struct Fts5PhraseIter
10099 {
10100     const(ubyte)* a;
10101     const(ubyte)* b;
10102 }
10103 
10104 /*
10105 ** EXTENSION API FUNCTIONS
10106 **
10107 ** xUserData(pFts):
10108 **   Return a copy of the context pointer the extension function was
10109 **   registered with.
10110 **
10111 ** xColumnTotalSize(pFts, iCol, pnToken):
10112 **   If parameter iCol is less than zero, set output variable *pnToken
10113 **   to the total number of tokens in the FTS5 table. Or, if iCol is
10114 **   non-negative but less than the number of columns in the table, return
10115 **   the total number of tokens in column iCol, considering all rows in
10116 **   the FTS5 table.
10117 **
10118 **   If parameter iCol is greater than or equal to the number of columns
10119 **   in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
10120 **   an OOM condition or IO error), an appropriate SQLite error code is
10121 **   returned.
10122 **
10123 ** xColumnCount(pFts):
10124 **   Return the number of columns in the table.
10125 **
10126 ** xColumnSize(pFts, iCol, pnToken):
10127 **   If parameter iCol is less than zero, set output variable *pnToken
10128 **   to the total number of tokens in the current row. Or, if iCol is
10129 **   non-negative but less than the number of columns in the table, set
10130 **   *pnToken to the number of tokens in column iCol of the current row.
10131 **
10132 **   If parameter iCol is greater than or equal to the number of columns
10133 **   in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
10134 **   an OOM condition or IO error), an appropriate SQLite error code is
10135 **   returned.
10136 **
10137 **   This function may be quite inefficient if used with an FTS5 table
10138 **   created with the "columnsize=0" option.
10139 **
10140 ** xColumnText:
10141 **   This function attempts to retrieve the text of column iCol of the
10142 **   current document. If successful, (*pz) is set to point to a buffer
10143 **   containing the text in utf-8 encoding, (*pn) is set to the size in bytes
10144 **   (not characters) of the buffer and SQLITE_OK is returned. Otherwise,
10145 **   if an error occurs, an SQLite error code is returned and the final values
10146 **   of (*pz) and (*pn) are undefined.
10147 **
10148 ** xPhraseCount:
10149 **   Returns the number of phrases in the current query expression.
10150 **
10151 ** xPhraseSize:
10152 **   Returns the number of tokens in phrase iPhrase of the query. Phrases
10153 **   are numbered starting from zero.
10154 **
10155 ** xInstCount:
10156 **   Set *pnInst to the total number of occurrences of all phrases within
10157 **   the query within the current row. Return SQLITE_OK if successful, or
10158 **   an error code (i.e. SQLITE_NOMEM) if an error occurs.
10159 **
10160 **   This API can be quite slow if used with an FTS5 table created with the
10161 **   "detail=none" or "detail=column" option. If the FTS5 table is created
10162 **   with either "detail=none" or "detail=column" and "content=" option
10163 **   (i.e. if it is a contentless table), then this API always returns 0.
10164 **
10165 ** xInst:
10166 **   Query for the details of phrase match iIdx within the current row.
10167 **   Phrase matches are numbered starting from zero, so the iIdx argument
10168 **   should be greater than or equal to zero and smaller than the value
10169 **   output by xInstCount().
10170 **
10171 **   Usually, output parameter *piPhrase is set to the phrase number, *piCol
10172 **   to the column in which it occurs and *piOff the token offset of the
10173 **   first token of the phrase. The exception is if the table was created
10174 **   with the offsets=0 option specified. In this case *piOff is always
10175 **   set to -1.
10176 **
10177 **   Returns SQLITE_OK if successful, or an error code (i.e. SQLITE_NOMEM)
10178 **   if an error occurs.
10179 **
10180 **   This API can be quite slow if used with an FTS5 table created with the
10181 **   "detail=none" or "detail=column" option.
10182 **
10183 ** xRowid:
10184 **   Returns the rowid of the current row.
10185 **
10186 ** xTokenize:
10187 **   Tokenize text using the tokenizer belonging to the FTS5 table.
10188 **
10189 ** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback):
10190 **   This API function is used to query the FTS table for phrase iPhrase
10191 **   of the current query. Specifically, a query equivalent to:
10192 **
10193 **       ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid
10194 **
10195 **   with $p set to a phrase equivalent to the phrase iPhrase of the
10196 **   current query is executed. Any column filter that applies to
10197 **   phrase iPhrase of the current query is included in $p. For each
10198 **   row visited, the callback function passed as the fourth argument
10199 **   is invoked. The context and API objects passed to the callback
10200 **   function may be used to access the properties of each matched row.
10201 **   Invoking Api.xUserData() returns a copy of the pointer passed as
10202 **   the third argument to pUserData.
10203 **
10204 **   If the callback function returns any value other than SQLITE_OK, the
10205 **   query is abandoned and the xQueryPhrase function returns immediately.
10206 **   If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK.
10207 **   Otherwise, the error code is propagated upwards.
10208 **
10209 **   If the query runs to completion without incident, SQLITE_OK is returned.
10210 **   Or, if some error occurs before the query completes or is aborted by
10211 **   the callback, an SQLite error code is returned.
10212 **
10213 **
10214 ** xSetAuxdata(pFts5, pAux, xDelete)
10215 **
10216 **   Save the pointer passed as the second argument as the extension functions
10217 **   "auxiliary data". The pointer may then be retrieved by the current or any
10218 **   future invocation of the same fts5 extension function made as part of
10219 **   of the same MATCH query using the xGetAuxdata() API.
10220 **
10221 **   Each extension function is allocated a single auxiliary data slot for
10222 **   each FTS query (MATCH expression). If the extension function is invoked
10223 **   more than once for a single FTS query, then all invocations share a
10224 **   single auxiliary data context.
10225 **
10226 **   If there is already an auxiliary data pointer when this function is
10227 **   invoked, then it is replaced by the new pointer. If an xDelete callback
10228 **   was specified along with the original pointer, it is invoked at this
10229 **   point.
10230 **
10231 **   The xDelete callback, if one is specified, is also invoked on the
10232 **   auxiliary data pointer after the FTS5 query has finished.
10233 **
10234 **   If an error (e.g. an OOM condition) occurs within this function, an
10235 **   the auxiliary data is set to NULL and an error code returned. If the
10236 **   xDelete parameter was not NULL, it is invoked on the auxiliary data
10237 **   pointer before returning.
10238 **
10239 **
10240 ** xGetAuxdata(pFts5, bClear)
10241 **
10242 **   Returns the current auxiliary data pointer for the fts5 extension
10243 **   function. See the xSetAuxdata() method for details.
10244 **
10245 **   If the bClear argument is non-zero, then the auxiliary data is cleared
10246 **   (set to NULL) before this function returns. In this case the xDelete,
10247 **   if any, is not invoked.
10248 **
10249 **
10250 ** xRowCount(pFts5, pnRow)
10251 **
10252 **   This function is used to retrieve the total number of rows in the table.
10253 **   In other words, the same value that would be returned by:
10254 **
10255 **        SELECT count(*) FROM ftstable;
10256 **
10257 ** xPhraseFirst()
10258 **   This function is used, along with type Fts5PhraseIter and the xPhraseNext
10259 **   method, to iterate through all instances of a single query phrase within
10260 **   the current row. This is the same information as is accessible via the
10261 **   xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient
10262 **   to use, this API may be faster under some circumstances. To iterate
10263 **   through instances of phrase iPhrase, use the following code:
10264 **
10265 **       Fts5PhraseIter iter;
10266 **       int iCol, iOff;
10267 **       for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff);
10268 **           iCol>=0;
10269 **           pApi->xPhraseNext(pFts, &iter, &iCol, &iOff)
10270 **       ){
10271 **         // An instance of phrase iPhrase at offset iOff of column iCol
10272 **       }
10273 **
10274 **   The Fts5PhraseIter structure is defined above. Applications should not
10275 **   modify this structure directly - it should only be used as shown above
10276 **   with the xPhraseFirst() and xPhraseNext() API methods (and by
10277 **   xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below).
10278 **
10279 **   This API can be quite slow if used with an FTS5 table created with the
10280 **   "detail=none" or "detail=column" option. If the FTS5 table is created
10281 **   with either "detail=none" or "detail=column" and "content=" option
10282 **   (i.e. if it is a contentless table), then this API always iterates
10283 **   through an empty set (all calls to xPhraseFirst() set iCol to -1).
10284 **
10285 ** xPhraseNext()
10286 **   See xPhraseFirst above.
10287 **
10288 ** xPhraseFirstColumn()
10289 **   This function and xPhraseNextColumn() are similar to the xPhraseFirst()
10290 **   and xPhraseNext() APIs described above. The difference is that instead
10291 **   of iterating through all instances of a phrase in the current row, these
10292 **   APIs are used to iterate through the set of columns in the current row
10293 **   that contain one or more instances of a specified phrase. For example:
10294 **
10295 **       Fts5PhraseIter iter;
10296 **       int iCol;
10297 **       for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol);
10298 **           iCol>=0;
10299 **           pApi->xPhraseNextColumn(pFts, &iter, &iCol)
10300 **       ){
10301 **         // Column iCol contains at least one instance of phrase iPhrase
10302 **       }
10303 **
10304 **   This API can be quite slow if used with an FTS5 table created with the
10305 **   "detail=none" option. If the FTS5 table is created with either
10306 **   "detail=none" "content=" option (i.e. if it is a contentless table),
10307 **   then this API always iterates through an empty set (all calls to
10308 **   xPhraseFirstColumn() set iCol to -1).
10309 **
10310 **   The information accessed using this API and its companion
10311 **   xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext
10312 **   (or xInst/xInstCount). The chief advantage of this API is that it is
10313 **   significantly more efficient than those alternatives when used with
10314 **   "detail=column" tables.
10315 **
10316 ** xPhraseNextColumn()
10317 **   See xPhraseFirstColumn above.
10318 */
10319 struct Fts5ExtensionApi
10320 {
10321     int iVersion; /* Currently always set to 3 */
10322 
10323     void* function(Fts5Context*) xUserData;
10324 
10325     int function(Fts5Context*) xColumnCount;
10326     int function(Fts5Context*, sqlite3_int64* pnRow) xRowCount;
10327     int function(Fts5Context*, int iCol, sqlite3_int64* pnToken) xColumnTotalSize;
10328 
10329     /* Text to tokenize */
10330     /* Context passed to xToken() */
10331     /* Callback */
10332     int function(Fts5Context*, const(char)* pText, int nText, void* pCtx, int function(void*, int, const(char)*, int, int, int) xToken) xTokenize;
10333 
10334     int function(Fts5Context*) xPhraseCount;
10335     int function(Fts5Context*, int iPhrase) xPhraseSize;
10336 
10337     int function(Fts5Context*, int* pnInst) xInstCount;
10338     int function(Fts5Context*, int iIdx, int* piPhrase, int* piCol, int* piOff) xInst;
10339 
10340     sqlite3_int64 function(Fts5Context*) xRowid;
10341     int function(Fts5Context*, int iCol, const(char*)* pz, int* pn) xColumnText;
10342     int function(Fts5Context*, int iCol, int* pnToken) xColumnSize;
10343 
10344     int function(Fts5Context*, int iPhrase, void* pUserData, int function(const(Fts5ExtensionApi)*, Fts5Context*, void*)) xQueryPhrase;
10345     int function(Fts5Context*, void* pAux, void function(void*) xDelete) xSetAuxdata;
10346     void* function(Fts5Context*, int bClear) xGetAuxdata;
10347 
10348     int function(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*) xPhraseFirst;
10349     void function(Fts5Context*, Fts5PhraseIter*, int* piCol, int* piOff) xPhraseNext;
10350 
10351     int function(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*) xPhraseFirstColumn;
10352     void function(Fts5Context*, Fts5PhraseIter*, int* piCol) xPhraseNextColumn;
10353 }
10354 
10355 /*
10356 ** CUSTOM AUXILIARY FUNCTIONS
10357 *************************************************************************/
10358 
10359 /*************************************************************************
10360 ** CUSTOM TOKENIZERS
10361 **
10362 ** Applications may also register custom tokenizer types. A tokenizer
10363 ** is registered by providing fts5 with a populated instance of the
10364 ** following structure. All structure methods must be defined, setting
10365 ** any member of the fts5_tokenizer struct to NULL leads to undefined
10366 ** behaviour. The structure methods are expected to function as follows:
10367 **
10368 ** xCreate:
10369 **   This function is used to allocate and initialize a tokenizer instance.
10370 **   A tokenizer instance is required to actually tokenize text.
10371 **
10372 **   The first argument passed to this function is a copy of the (void*)
10373 **   pointer provided by the application when the fts5_tokenizer object
10374 **   was registered with FTS5 (the third argument to xCreateTokenizer()).
10375 **   The second and third arguments are an array of nul-terminated strings
10376 **   containing the tokenizer arguments, if any, specified following the
10377 **   tokenizer name as part of the CREATE VIRTUAL TABLE statement used
10378 **   to create the FTS5 table.
10379 **
10380 **   The final argument is an output variable. If successful, (*ppOut)
10381 **   should be set to point to the new tokenizer handle and SQLITE_OK
10382 **   returned. If an error occurs, some value other than SQLITE_OK should
10383 **   be returned. In this case, fts5 assumes that the final value of *ppOut
10384 **   is undefined.
10385 **
10386 ** xDelete:
10387 **   This function is invoked to delete a tokenizer handle previously
10388 **   allocated using xCreate(). Fts5 guarantees that this function will
10389 **   be invoked exactly once for each successful call to xCreate().
10390 **
10391 ** xTokenize:
10392 **   This function is expected to tokenize the nText byte string indicated
10393 **   by argument pText. pText may or may not be nul-terminated. The first
10394 **   argument passed to this function is a pointer to an Fts5Tokenizer object
10395 **   returned by an earlier call to xCreate().
10396 **
10397 **   The second argument indicates the reason that FTS5 is requesting
10398 **   tokenization of the supplied text. This is always one of the following
10399 **   four values:
10400 **
10401 **   <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into
10402 **            or removed from the FTS table. The tokenizer is being invoked to
10403 **            determine the set of tokens to add to (or delete from) the
10404 **            FTS index.
10405 **
10406 **       <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed
10407 **            against the FTS index. The tokenizer is being called to tokenize
10408 **            a bareword or quoted string specified as part of the query.
10409 **
10410 **       <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as
10411 **            FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is
10412 **            followed by a "*" character, indicating that the last token
10413 **            returned by the tokenizer will be treated as a token prefix.
10414 **
10415 **       <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to
10416 **            satisfy an fts5_api.xTokenize() request made by an auxiliary
10417 **            function. Or an fts5_api.xColumnSize() request made by the same
10418 **            on a columnsize=0 database.
10419 **   </ul>
10420 **
10421 **   For each token in the input string, the supplied callback xToken() must
10422 **   be invoked. The first argument to it should be a copy of the pointer
10423 **   passed as the second argument to xTokenize(). The third and fourth
10424 **   arguments are a pointer to a buffer containing the token text, and the
10425 **   size of the token in bytes. The 4th and 5th arguments are the byte offsets
10426 **   of the first byte of and first byte immediately following the text from
10427 **   which the token is derived within the input.
10428 **
10429 **   The second argument passed to the xToken() callback ("tflags") should
10430 **   normally be set to 0. The exception is if the tokenizer supports
10431 **   synonyms. In this case see the discussion below for details.
10432 **
10433 **   FTS5 assumes the xToken() callback is invoked for each token in the
10434 **   order that they occur within the input text.
10435 **
10436 **   If an xToken() callback returns any value other than SQLITE_OK, then
10437 **   the tokenization should be abandoned and the xTokenize() method should
10438 **   immediately return a copy of the xToken() return value. Or, if the
10439 **   input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally,
10440 **   if an error occurs with the xTokenize() implementation itself, it
10441 **   may abandon the tokenization and return any error code other than
10442 **   SQLITE_OK or SQLITE_DONE.
10443 **
10444 ** SYNONYM SUPPORT
10445 **
10446 **   Custom tokenizers may also support synonyms. Consider a case in which a
10447 **   user wishes to query for a phrase such as "first place". Using the
10448 **   built-in tokenizers, the FTS5 query 'first + place' will match instances
10449 **   of "first place" within the document set, but not alternative forms
10450 **   such as "1st place". In some applications, it would be better to match
10451 **   all instances of "first place" or "1st place" regardless of which form
10452 **   the user specified in the MATCH query text.
10453 **
10454 **   There are several ways to approach this in FTS5:
10455 **
10456 **   <ol><li> By mapping all synonyms to a single token. In this case, the
10457 **            In the above example, this means that the tokenizer returns the
10458 **            same token for inputs "first" and "1st". Say that token is in
10459 **            fact "first", so that when the user inserts the document "I won
10460 **            1st place" entries are added to the index for tokens "i", "won",
10461 **            "first" and "place". If the user then queries for '1st + place',
10462 **            the tokenizer substitutes "first" for "1st" and the query works
10463 **            as expected.
10464 **
10465 **       <li> By adding multiple synonyms for a single term to the FTS index.
10466 **            In this case, when tokenizing query text, the tokenizer may
10467 **            provide multiple synonyms for a single term within the document.
10468 **            FTS5 then queries the index for each synonym individually. For
10469 **            example, faced with the query:
10470 **
10471 **   <codeblock>
10472 **     ... MATCH 'first place'</codeblock>
10473 **
10474 **            the tokenizer offers both "1st" and "first" as synonyms for the
10475 **            first token in the MATCH query and FTS5 effectively runs a query
10476 **            similar to:
10477 **
10478 **   <codeblock>
10479 **     ... MATCH '(first OR 1st) place'</codeblock>
10480 **
10481 **            except that, for the purposes of auxiliary functions, the query
10482 **            still appears to contain just two phrases - "(first OR 1st)"
10483 **            being treated as a single phrase.
10484 **
10485 **       <li> By adding multiple synonyms for a single term to the FTS index.
10486 **            Using this method, when tokenizing document text, the tokenizer
10487 **            provides multiple synonyms for each token. So that when a
10488 **            document such as "I won first place" is tokenized, entries are
10489 **            added to the FTS index for "i", "won", "first", "1st" and
10490 **            "place".
10491 **
10492 **            This way, even if the tokenizer does not provide synonyms
10493 **            when tokenizing query text (it should not - to do would be
10494 **            inefficient), it doesn't matter if the user queries for
10495 **            'first + place' or '1st + place', as there are entires in the
10496 **            FTS index corresponding to both forms of the first token.
10497 **   </ol>
10498 **
10499 **   Whether it is parsing document or query text, any call to xToken that
10500 **   specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit
10501 **   is considered to supply a synonym for the previous token. For example,
10502 **   when parsing the document "I won first place", a tokenizer that supports
10503 **   synonyms would call xToken() 5 times, as follows:
10504 **
10505 **   <codeblock>
10506 **       xToken(pCtx, 0, "i",                      1,  0,  1);
10507 **       xToken(pCtx, 0, "won",                    3,  2,  5);
10508 **       xToken(pCtx, 0, "first",                  5,  6, 11);
10509 **       xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3,  6, 11);
10510 **       xToken(pCtx, 0, "place",                  5, 12, 17);
10511 **</codeblock>
10512 **
10513 **   It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time
10514 **   xToken() is called. Multiple synonyms may be specified for a single token
10515 **   by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence.
10516 **   There is no limit to the number of synonyms that may be provided for a
10517 **   single token.
10518 **
10519 **   In many cases, method (1) above is the best approach. It does not add
10520 **   extra data to the FTS index or require FTS5 to query for multiple terms,
10521 **   so it is efficient in terms of disk space and query speed. However, it
10522 **   does not support prefix queries very well. If, as suggested above, the
10523 **   token "first" is subsituted for "1st" by the tokenizer, then the query:
10524 **
10525 **   <codeblock>
10526 **     ... MATCH '1s*'</codeblock>
10527 **
10528 **   will not match documents that contain the token "1st" (as the tokenizer
10529 **   will probably not map "1s" to any prefix of "first").
10530 **
10531 **   For full prefix support, method (3) may be preferred. In this case,
10532 **   because the index contains entries for both "first" and "1st", prefix
10533 **   queries such as 'fi*' or '1s*' will match correctly. However, because
10534 **   extra entries are added to the FTS index, this method uses more space
10535 **   within the database.
10536 **
10537 **   Method (2) offers a midpoint between (1) and (3). Using this method,
10538 **   a query such as '1s*' will match documents that contain the literal
10539 **   token "1st", but not "first" (assuming the tokenizer is not able to
10540 **   provide synonyms for prefixes). However, a non-prefix query like '1st'
10541 **   will match against "1st" and "first". This method does not require
10542 **   extra disk space, as no extra entries are added to the FTS index.
10543 **   On the other hand, it may require more CPU cycles to run MATCH queries,
10544 **   as separate queries of the FTS index are required for each synonym.
10545 **
10546 **   When using methods (2) or (3), it is important that the tokenizer only
10547 **   provide synonyms when tokenizing document text (method (2)) or query
10548 **   text (method (3)), not both. Doing so will not cause any errors, but is
10549 **   inefficient.
10550 */
10551 struct Fts5Tokenizer;
10552 
10553 struct fts5_tokenizer
10554 {
10555     int function(void*, const(char*)* azArg, int nArg, Fts5Tokenizer** ppOut) xCreate;
10556     void function(Fts5Tokenizer*) xDelete;
10557 
10558     /* Mask of FTS5_TOKENIZE_* flags */
10559 
10560     /* Copy of 2nd argument to xTokenize() */
10561     /* Mask of FTS5_TOKEN_* flags */
10562     /* Pointer to buffer containing token */
10563     /* Size of token in bytes */
10564     /* Byte offset of token within input text */
10565     /* Byte offset of end of token within input text */
10566     int function(Fts5Tokenizer*, void* pCtx, int flags, const(char)* pText, int nText, int function(void* pCtx, int tflags, const(char)* pToken, int nToken, int iStart, int iEnd) xToken) xTokenize;
10567 }
10568 
10569 /* Flags that may be passed as the third argument to xTokenize() */
10570 enum FTS5_TOKENIZE_QUERY = 0x0001;
10571 enum FTS5_TOKENIZE_PREFIX = 0x0002;
10572 enum FTS5_TOKENIZE_DOCUMENT = 0x0004;
10573 enum FTS5_TOKENIZE_AUX = 0x0008;
10574 
10575 /* Flags that may be passed by the tokenizer implementation back to FTS5
10576 ** as the third argument to the supplied xToken callback. */
10577 enum FTS5_TOKEN_COLOCATED = 0x0001; /* Same position as prev. token */
10578 
10579 /*
10580 ** END OF CUSTOM TOKENIZERS
10581 *************************************************************************/
10582 
10583 /*************************************************************************
10584 ** FTS5 EXTENSION REGISTRATION API
10585 */
10586 struct fts5_api
10587 {
10588     int iVersion; /* Currently always set to 2 */
10589 
10590     /* Create a new tokenizer */
10591     int function(fts5_api* pApi, const(char)* zName, void* pContext, fts5_tokenizer* pTokenizer, void function(void*) xDestroy) xCreateTokenizer;
10592 
10593     /* Find an existing tokenizer */
10594     int function(fts5_api* pApi, const(char)* zName, void** ppContext, fts5_tokenizer* pTokenizer) xFindTokenizer;
10595 
10596     /* Create a new auxiliary function */
10597     int function(fts5_api* pApi, const(char)* zName, void* pContext, fts5_extension_function xFunction, void function(void*) xDestroy) xCreateFunction;
10598 }
10599 
10600 /*
10601 ** END OF REGISTRATION API
10602 *************************************************************************/
10603 
10604 /* end of the 'extern "C"' block */
10605 
10606 /* _FTS5_H */
10607 
10608 /******** End of fts5.h *********/