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  1. /*
  2. ** 2001 September 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 to make minor changes if
  22. ** 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 suppose 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. ** @(#) $Id$
  34. */
  35. #ifndef _SQLITE3_H_
  36. #define _SQLITE3_H_
  37. #include <stdarg.h> /* Needed for the definition of va_list */
  38. /*
  39. ** Make sure we can call this stuff from C++.
  40. */
  41. #ifdef __cplusplus
  42. extern "C" {
  43. #endif
  44. /*
  45. ** Add the ability to override 'extern'
  46. */
  47. #ifndef SQLITE_EXTERN
  48. # define SQLITE_EXTERN extern
  49. #endif
  50. /*
  51. ** Ensure these symbols were not defined by some previous header file.
  52. */
  53. #ifdef SQLITE_VERSION
  54. # undef SQLITE_VERSION
  55. #endif
  56. #ifdef SQLITE_VERSION_NUMBER
  57. # undef SQLITE_VERSION_NUMBER
  58. #endif
  59. /*
  60. ** CAPI3REF: Compile-Time Library Version Numbers {H10010} <S60100>
  61. **
  62. ** The SQLITE_VERSION and SQLITE_VERSION_NUMBER #defines in
  63. ** the sqlite3.h file specify the version of SQLite with which
  64. ** that header file is associated.
  65. **
  66. ** The "version" of SQLite is a string of the form "X.Y.Z".
  67. ** The phrase "alpha" or "beta" might be appended after the Z.
  68. ** The X value is major version number always 3 in SQLite3.
  69. ** The X value only changes when backwards compatibility is
  70. ** broken and we intend to never break backwards compatibility.
  71. ** The Y value is the minor version number and only changes when
  72. ** there are major feature enhancements that are forwards compatible
  73. ** but not backwards compatible.
  74. ** The Z value is the release number and is incremented with
  75. ** each release but resets back to 0 whenever Y is incremented.
  76. **
  77. ** See also: [sqlite3_libversion()] and [sqlite3_libversion_number()].
  78. **
  79. ** INVARIANTS:
  80. **
  81. ** {H10011} The SQLITE_VERSION #define in the sqlite3.h header file shall
  82. ** evaluate to a string literal that is the SQLite version
  83. ** with which the header file is associated.
  84. **
  85. ** {H10014} The SQLITE_VERSION_NUMBER #define shall resolve to an integer
  86. ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z
  87. ** are the major version, minor version, and release number.
  88. */
  89. #define SQLITE_VERSION "3.6.1"
  90. #define SQLITE_VERSION_NUMBER 3006001
  91. /*
  92. ** CAPI3REF: Run-Time Library Version Numbers {H10020} <S60100>
  93. ** KEYWORDS: sqlite3_version
  94. **
  95. ** These features provide the same information as the [SQLITE_VERSION]
  96. ** and [SQLITE_VERSION_NUMBER] #defines in the header, but are associated
  97. ** with the library instead of the header file. Cautious programmers might
  98. ** include a check in their application to verify that
  99. ** sqlite3_libversion_number() always returns the value
  100. ** [SQLITE_VERSION_NUMBER].
  101. **
  102. ** The sqlite3_libversion() function returns the same information as is
  103. ** in the sqlite3_version[] string constant. The function is provided
  104. ** for use in DLLs since DLL users usually do not have direct access to string
  105. ** constants within the DLL.
  106. **
  107. ** INVARIANTS:
  108. **
  109. ** {H10021} The [sqlite3_libversion_number()] interface shall return
  110. ** an integer equal to [SQLITE_VERSION_NUMBER].
  111. **
  112. ** {H10022} The [sqlite3_version] string constant shall contain
  113. ** the text of the [SQLITE_VERSION] string.
  114. **
  115. ** {H10023} The [sqlite3_libversion()] function shall return
  116. ** a pointer to the [sqlite3_version] string constant.
  117. */
  118. SQLITE_EXTERN const char sqlite3_version[];
  119. const char *sqlite3_libversion(void);
  120. int sqlite3_libversion_number(void);
  121. /*
  122. ** CAPI3REF: Test To See If The Library Is Threadsafe {H10100} <S60100>
  123. **
  124. ** SQLite can be compiled with or without mutexes. When
  125. ** the [SQLITE_THREADSAFE] C preprocessor macro is true, mutexes
  126. ** are enabled and SQLite is threadsafe. When that macro is false,
  127. ** the mutexes are omitted. Without the mutexes, it is not safe
  128. ** to use SQLite concurrently from more than one thread.
  129. **
  130. ** Enabling mutexes incurs a measurable performance penalty.
  131. ** So if speed is of utmost importance, it makes sense to disable
  132. ** the mutexes. But for maximum safety, mutexes should be enabled.
  133. ** The default behavior is for mutexes to be enabled.
  134. **
  135. ** This interface can be used by a program to make sure that the
  136. ** version of SQLite that it is linking against was compiled with
  137. ** the desired setting of the [SQLITE_THREADSAFE] macro.
  138. **
  139. ** This interface only reports on the compile-time mutex setting
  140. ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
  141. ** SQLITE_THREADSAFE=1 then mutexes are enabled by default but
  142. ** can be fully or partially disabled using a call to [sqlite3_config()]
  143. ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
  144. ** or [SQLITE_CONFIG_MUTEX]. The return value of this function shows
  145. ** only the default compile-time setting, not any run-time changes
  146. ** to that setting.
  147. **
  148. ** INVARIANTS:
  149. **
  150. ** {H10101} The [sqlite3_threadsafe()] function shall return nonzero if
  151. ** SQLite was compiled with the its mutexes enabled by default
  152. ** or zero if SQLite was compiled such that mutexes are
  153. ** permanently disabled.
  154. **
  155. ** {H10102} The value returned by the [sqlite3_threadsafe()] function
  156. ** shall not change when mutex setting are modified at
  157. ** runtime using the [sqlite3_config()] interface and
  158. ** especially the [SQLITE_CONFIG_SINGLETHREAD],
  159. ** [SQLITE_CONFIG_MULTITHREAD], [SQLITE_CONFIG_SERIALIZED],
  160. ** and [SQLITE_CONFIG_MUTEX] verbs.
  161. */
  162. int sqlite3_threadsafe(void);
  163. /*
  164. ** CAPI3REF: Database Connection Handle {H12000} <S40200>
  165. ** KEYWORDS: {database connection} {database connections}
  166. **
  167. ** Each open SQLite database is represented by a pointer to an instance of
  168. ** the opaque structure named "sqlite3". It is useful to think of an sqlite3
  169. ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
  170. ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
  171. ** is its destructor. There are many other interfaces (such as
  172. ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
  173. ** [sqlite3_busy_timeout()] to name but three) that are methods on an
  174. ** sqlite3 object.
  175. */
  176. typedef struct sqlite3 sqlite3;
  177. /*
  178. ** CAPI3REF: 64-Bit Integer Types {H10200} <S10110>
  179. ** KEYWORDS: sqlite_int64 sqlite_uint64
  180. **
  181. ** Because there is no cross-platform way to specify 64-bit integer types
  182. ** SQLite includes typedefs for 64-bit signed and unsigned integers.
  183. **
  184. ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
  185. ** The sqlite_int64 and sqlite_uint64 types are supported for backwards
  186. ** compatibility only.
  187. **
  188. ** INVARIANTS:
  189. **
  190. ** {H10201} The [sqlite_int64] and [sqlite3_int64] type shall specify
  191. ** a 64-bit signed integer.
  192. **
  193. ** {H10202} The [sqlite_uint64] and [sqlite3_uint64] type shall specify
  194. ** a 64-bit unsigned integer.
  195. */
  196. #ifdef SQLITE_INT64_TYPE
  197. typedef SQLITE_INT64_TYPE sqlite_int64;
  198. typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
  199. #elif defined(_MSC_VER) || defined(__BORLANDC__)
  200. typedef __int64 sqlite_int64;
  201. typedef unsigned __int64 sqlite_uint64;
  202. #else
  203. typedef long long int sqlite_int64;
  204. typedef unsigned long long int sqlite_uint64;
  205. #endif
  206. typedef sqlite_int64 sqlite3_int64;
  207. typedef sqlite_uint64 sqlite3_uint64;
  208. /*
  209. ** If compiling for a processor that lacks floating point support,
  210. ** substitute integer for floating-point.
  211. */
  212. #ifdef SQLITE_OMIT_FLOATING_POINT
  213. # define double sqlite3_int64
  214. #endif
  215. /*
  216. ** CAPI3REF: Closing A Database Connection {H12010} <S30100><S40200>
  217. **
  218. ** This routine is the destructor for the [sqlite3] object.
  219. **
  220. ** Applications should [sqlite3_finalize | finalize] all [prepared statements]
  221. ** and [sqlite3_blob_close | close] all [BLOB handles] associated with
  222. ** the [sqlite3] object prior to attempting to close the object.
  223. ** The [sqlite3_next_stmt()] interface can be used to locate all
  224. ** [prepared statements] associated with a [database connection] if desired.
  225. ** Typical code might look like this:
  226. **
  227. ** <blockquote><pre>
  228. ** sqlite3_stmt *pStmt;
  229. ** while( (pStmt = sqlite3_next_stmt(db, 0))!=0 ){
  230. ** &nbsp; sqlite3_finalize(pStmt);
  231. ** }
  232. ** </pre></blockquote>
  233. **
  234. ** If [sqlite3_close()] is invoked while a transaction is open,
  235. ** the transaction is automatically rolled back.
  236. **
  237. ** INVARIANTS:
  238. **
  239. ** {H12011} A successful call to [sqlite3_close(C)] shall destroy the
  240. ** [database connection] object C.
  241. **
  242. ** {H12012} A successful call to [sqlite3_close(C)] shall return SQLITE_OK.
  243. **
  244. ** {H12013} A successful call to [sqlite3_close(C)] shall release all
  245. ** memory and system resources associated with [database connection]
  246. ** C.
  247. **
  248. ** {H12014} A call to [sqlite3_close(C)] on a [database connection] C that
  249. ** has one or more open [prepared statements] shall fail with
  250. ** an [SQLITE_BUSY] error code.
  251. **
  252. ** {H12015} A call to [sqlite3_close(C)] where C is a NULL pointer shall
  253. ** return SQLITE_OK.
  254. **
  255. ** {H12019} When [sqlite3_close(C)] is invoked on a [database connection] C
  256. ** that has a pending transaction, the transaction shall be
  257. ** rolled back.
  258. **
  259. ** ASSUMPTIONS:
  260. **
  261. ** {A12016} The C parameter to [sqlite3_close(C)] must be either a NULL
  262. ** pointer or an [sqlite3] object pointer obtained
  263. ** from [sqlite3_open()], [sqlite3_open16()], or
  264. ** [sqlite3_open_v2()], and not previously closed.
  265. */
  266. int sqlite3_close(sqlite3 *);
  267. /*
  268. ** The type for a callback function.
  269. ** This is legacy and deprecated. It is included for historical
  270. ** compatibility and is not documented.
  271. */
  272. typedef int (*sqlite3_callback)(void*,int,char**, char**);
  273. /*
  274. ** CAPI3REF: One-Step Query Execution Interface {H12100} <S10000>
  275. **
  276. ** The sqlite3_exec() interface is a convenient way of running one or more
  277. ** SQL statements without having to write a lot of C code. The UTF-8 encoded
  278. ** SQL statements are passed in as the second parameter to sqlite3_exec().
  279. ** The statements are evaluated one by one until either an error or
  280. ** an interrupt is encountered, or until they are all done. The 3rd parameter
  281. ** is an optional callback that is invoked once for each row of any query
  282. ** results produced by the SQL statements. The 5th parameter tells where
  283. ** to write any error messages.
  284. **
  285. ** The error message passed back through the 5th parameter is held
  286. ** in memory obtained from [sqlite3_malloc()]. To avoid a memory leak,
  287. ** the calling application should call [sqlite3_free()] on any error
  288. ** message returned through the 5th parameter when it has finished using
  289. ** the error message.
  290. **
  291. ** If the SQL statement in the 2nd parameter is NULL or an empty string
  292. ** or a string containing only whitespace and comments, then no SQL
  293. ** statements are evaluated and the database is not changed.
  294. **
  295. ** The sqlite3_exec() interface is implemented in terms of
  296. ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()].
  297. ** The sqlite3_exec() routine does nothing to the database that cannot be done
  298. ** by [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()].
  299. **
  300. ** INVARIANTS:
  301. **
  302. ** {H12101} A successful invocation of [sqlite3_exec(D,S,C,A,E)]
  303. ** shall sequentially evaluate all of the UTF-8 encoded,
  304. ** semicolon-separated SQL statements in the zero-terminated
  305. ** string S within the context of the [database connection] D.
  306. **
  307. ** {H12102} If the S parameter to [sqlite3_exec(D,S,C,A,E)] is NULL then
  308. ** the actions of the interface shall be the same as if the
  309. ** S parameter were an empty string.
  310. **
  311. ** {H12104} The return value of [sqlite3_exec()] shall be [SQLITE_OK] if all
  312. ** SQL statements run successfully and to completion.
  313. **
  314. ** {H12105} The return value of [sqlite3_exec()] shall be an appropriate
  315. ** non-zero [error code] if any SQL statement fails.
  316. **
  317. ** {H12107} If one or more of the SQL statements handed to [sqlite3_exec()]
  318. ** return results and the 3rd parameter is not NULL, then
  319. ** the callback function specified by the 3rd parameter shall be
  320. ** invoked once for each row of result.
  321. **
  322. ** {H12110} If the callback returns a non-zero value then [sqlite3_exec()]
  323. ** shall abort the SQL statement it is currently evaluating,
  324. ** skip all subsequent SQL statements, and return [SQLITE_ABORT].
  325. **
  326. ** {H12113} The [sqlite3_exec()] routine shall pass its 4th parameter through
  327. ** as the 1st parameter of the callback.
  328. **
  329. ** {H12116} The [sqlite3_exec()] routine shall set the 2nd parameter of its
  330. ** callback to be the number of columns in the current row of
  331. ** result.
  332. **
  333. ** {H12119} The [sqlite3_exec()] routine shall set the 3rd parameter of its
  334. ** callback to be an array of pointers to strings holding the
  335. ** values for each column in the current result set row as
  336. ** obtained from [sqlite3_column_text()].
  337. **
  338. ** {H12122} The [sqlite3_exec()] routine shall set the 4th parameter of its
  339. ** callback to be an array of pointers to strings holding the
  340. ** names of result columns as obtained from [sqlite3_column_name()].
  341. **
  342. ** {H12125} If the 3rd parameter to [sqlite3_exec()] is NULL then
  343. ** [sqlite3_exec()] shall silently discard query results.
  344. **
  345. ** {H12131} If an error occurs while parsing or evaluating any of the SQL
  346. ** statements in the S parameter of [sqlite3_exec(D,S,C,A,E)] and if
  347. ** the E parameter is not NULL, then [sqlite3_exec()] shall store
  348. ** in *E an appropriate error message written into memory obtained
  349. ** from [sqlite3_malloc()].
  350. **
  351. ** {H12134} The [sqlite3_exec(D,S,C,A,E)] routine shall set the value of
  352. ** *E to NULL if E is not NULL and there are no errors.
  353. **
  354. ** {H12137} The [sqlite3_exec(D,S,C,A,E)] function shall set the [error code]
  355. ** and message accessible via [sqlite3_errcode()],
  356. ** [sqlite3_errmsg()], and [sqlite3_errmsg16()].
  357. **
  358. ** {H12138} If the S parameter to [sqlite3_exec(D,S,C,A,E)] is NULL or an
  359. ** empty string or contains nothing other than whitespace, comments,
  360. ** and/or semicolons, then results of [sqlite3_errcode()],
  361. ** [sqlite3_errmsg()], and [sqlite3_errmsg16()]
  362. ** shall reset to indicate no errors.
  363. **
  364. ** ASSUMPTIONS:
  365. **
  366. ** {A12141} The first parameter to [sqlite3_exec()] must be an valid and open
  367. ** [database connection].
  368. **
  369. ** {A12142} The database connection must not be closed while
  370. ** [sqlite3_exec()] is running.
  371. **
  372. ** {A12143} The calling function should use [sqlite3_free()] to free
  373. ** the memory that *errmsg is left pointing at once the error
  374. ** message is no longer needed.
  375. **
  376. ** {A12145} The SQL statement text in the 2nd parameter to [sqlite3_exec()]
  377. ** must remain unchanged while [sqlite3_exec()] is running.
  378. */
  379. int sqlite3_exec(
  380. sqlite3*, /* An open database */
  381. const char *sql, /* SQL to be evaluated */
  382. int (*callback)(void*,int,char**,char**), /* Callback function */
  383. void *, /* 1st argument to callback */
  384. char **errmsg /* Error msg written here */
  385. );
  386. /*
  387. ** CAPI3REF: Result Codes {H10210} <S10700>
  388. ** KEYWORDS: SQLITE_OK {error code} {error codes}
  389. ** KEYWORDS: {result code} {result codes}
  390. **
  391. ** Many SQLite functions return an integer result code from the set shown
  392. ** here in order to indicates success or failure.
  393. **
  394. ** New error codes may be added in future versions of SQLite.
  395. **
  396. ** See also: [SQLITE_IOERR_READ | extended result codes]
  397. */
  398. #define SQLITE_OK 0 /* Successful result */
  399. /* beginning-of-error-codes */
  400. #define SQLITE_ERROR 1 /* SQL error or missing database */
  401. #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
  402. #define SQLITE_PERM 3 /* Access permission denied */
  403. #define SQLITE_ABORT 4 /* Callback routine requested an abort */
  404. #define SQLITE_BUSY 5 /* The database file is locked */
  405. #define SQLITE_LOCKED 6 /* A table in the database is locked */
  406. #define SQLITE_NOMEM 7 /* A malloc() failed */
  407. #define SQLITE_READONLY 8 /* Attempt to write a readonly database */
  408. #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
  409. #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
  410. #define SQLITE_CORRUPT 11 /* The database disk image is malformed */
  411. #define SQLITE_NOTFOUND 12 /* NOT USED. Table or record not found */
  412. #define SQLITE_FULL 13 /* Insertion failed because database is full */
  413. #define SQLITE_CANTOPEN 14 /* Unable to open the database file */
  414. #define SQLITE_PROTOCOL 15 /* NOT USED. Database lock protocol error */
  415. #define SQLITE_EMPTY 16 /* Database is empty */
  416. #define SQLITE_SCHEMA 17 /* The database schema changed */
  417. #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
  418. #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
  419. #define SQLITE_MISMATCH 20 /* Data type mismatch */
  420. #define SQLITE_MISUSE 21 /* Library used incorrectly */
  421. #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
  422. #define SQLITE_AUTH 23 /* Authorization denied */
  423. #define SQLITE_FORMAT 24 /* Auxiliary database format error */
  424. #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
  425. #define SQLITE_NOTADB 26 /* File opened that is not a database file */
  426. #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
  427. #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
  428. /* end-of-error-codes */
  429. /*
  430. ** CAPI3REF: Extended Result Codes {H10220} <S10700>
  431. ** KEYWORDS: {extended error code} {extended error codes}
  432. ** KEYWORDS: {extended result code} {extended result codes}
  433. **
  434. ** In its default configuration, SQLite API routines return one of 26 integer
  435. ** [SQLITE_OK | result codes]. However, experience has shown that many of
  436. ** these result codes are too coarse-grained. They do not provide as
  437. ** much information about problems as programmers might like. In an effort to
  438. ** address this, newer versions of SQLite (version 3.3.8 and later) include
  439. ** support for additional result codes that provide more detailed information
  440. ** about errors. The extended result codes are enabled or disabled
  441. ** on a per database connection basis using the
  442. ** [sqlite3_extended_result_codes()] API.
  443. **
  444. ** Some of the available extended result codes are listed here.
  445. ** One may expect the number of extended result codes will be expand
  446. ** over time. Software that uses extended result codes should expect
  447. ** to see new result codes in future releases of SQLite.
  448. **
  449. ** The SQLITE_OK result code will never be extended. It will always
  450. ** be exactly zero.
  451. **
  452. ** INVARIANTS:
  453. **
  454. ** {H10223} The symbolic name for an extended result code shall contains
  455. ** a related primary result code as a prefix.
  456. **
  457. ** {H10224} Primary result code names shall contain a single "_" character.
  458. **
  459. ** {H10225} Extended result code names shall contain two or more "_" characters.
  460. **
  461. ** {H10226} The numeric value of an extended result code shall contain the
  462. ** numeric value of its corresponding primary result code in
  463. ** its least significant 8 bits.
  464. */
  465. #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
  466. #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
  467. #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
  468. #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
  469. #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
  470. #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
  471. #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
  472. #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
  473. #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
  474. #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
  475. #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
  476. #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
  477. #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
  478. #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
  479. /*
  480. ** CAPI3REF: Flags For File Open Operations {H10230} <H11120> <H12700>
  481. **
  482. ** These bit values are intended for use in the
  483. ** 3rd parameter to the [sqlite3_open_v2()] interface and
  484. ** in the 4th parameter to the xOpen method of the
  485. ** [sqlite3_vfs] object.
  486. */
  487. #define SQLITE_OPEN_READONLY 0x00000001
  488. #define SQLITE_OPEN_READWRITE 0x00000002
  489. #define SQLITE_OPEN_CREATE 0x00000004
  490. #define SQLITE_OPEN_DELETEONCLOSE 0x00000008
  491. #define SQLITE_OPEN_EXCLUSIVE 0x00000010
  492. #define SQLITE_OPEN_MAIN_DB 0x00000100
  493. #define SQLITE_OPEN_TEMP_DB 0x00000200
  494. #define SQLITE_OPEN_TRANSIENT_DB 0x00000400
  495. #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800
  496. #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000
  497. #define SQLITE_OPEN_SUBJOURNAL 0x00002000
  498. #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000
  499. #define SQLITE_OPEN_NOMUTEX 0x00008000
  500. /*
  501. ** CAPI3REF: Device Characteristics {H10240} <H11120>
  502. **
  503. ** The xDeviceCapabilities method of the [sqlite3_io_methods]
  504. ** object returns an integer which is a vector of the these
  505. ** bit values expressing I/O characteristics of the mass storage
  506. ** device that holds the file that the [sqlite3_io_methods]
  507. ** refers to.
  508. **
  509. ** The SQLITE_IOCAP_ATOMIC property means that all writes of
  510. ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
  511. ** mean that writes of blocks that are nnn bytes in size and
  512. ** are aligned to an address which is an integer multiple of
  513. ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
  514. ** that when data is appended to a file, the data is appended
  515. ** first then the size of the file is extended, never the other
  516. ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
  517. ** information is written to disk in the same order as calls
  518. ** to xWrite().
  519. */
  520. #define SQLITE_IOCAP_ATOMIC 0x00000001
  521. #define SQLITE_IOCAP_ATOMIC512 0x00000002
  522. #define SQLITE_IOCAP_ATOMIC1K 0x00000004
  523. #define SQLITE_IOCAP_ATOMIC2K 0x00000008
  524. #define SQLITE_IOCAP_ATOMIC4K 0x00000010
  525. #define SQLITE_IOCAP_ATOMIC8K 0x00000020
  526. #define SQLITE_IOCAP_ATOMIC16K 0x00000040
  527. #define SQLITE_IOCAP_ATOMIC32K 0x00000080
  528. #define SQLITE_IOCAP_ATOMIC64K 0x00000100
  529. #define SQLITE_IOCAP_SAFE_APPEND 0x00000200
  530. #define SQLITE_IOCAP_SEQUENTIAL 0x00000400
  531. /*
  532. ** CAPI3REF: File Locking Levels {H10250} <H11120> <H11310>
  533. **
  534. ** SQLite uses one of these integer values as the second
  535. ** argument to calls it makes to the xLock() and xUnlock() methods
  536. ** of an [sqlite3_io_methods] object.
  537. */
  538. #define SQLITE_LOCK_NONE 0
  539. #define SQLITE_LOCK_SHARED 1
  540. #define SQLITE_LOCK_RESERVED 2
  541. #define SQLITE_LOCK_PENDING 3
  542. #define SQLITE_LOCK_EXCLUSIVE 4
  543. /*
  544. ** CAPI3REF: Synchronization Type Flags {H10260} <H11120>
  545. **
  546. ** When SQLite invokes the xSync() method of an
  547. ** [sqlite3_io_methods] object it uses a combination of
  548. ** these integer values as the second argument.
  549. **
  550. ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
  551. ** sync operation only needs to flush data to mass storage. Inode
  552. ** information need not be flushed. The SQLITE_SYNC_NORMAL flag means
  553. ** to use normal fsync() semantics. The SQLITE_SYNC_FULL flag means
  554. ** to use Mac OS-X style fullsync instead of fsync().
  555. */
  556. #define SQLITE_SYNC_NORMAL 0x00002
  557. #define SQLITE_SYNC_FULL 0x00003
  558. #define SQLITE_SYNC_DATAONLY 0x00010
  559. /*
  560. ** CAPI3REF: OS Interface Open File Handle {H11110} <S20110>
  561. **
  562. ** An [sqlite3_file] object represents an open file in the OS
  563. ** interface layer. Individual OS interface implementations will
  564. ** want to subclass this object by appending additional fields
  565. ** for their own use. The pMethods entry is a pointer to an
  566. ** [sqlite3_io_methods] object that defines methods for performing
  567. ** I/O operations on the open file.
  568. */
  569. typedef struct sqlite3_file sqlite3_file;
  570. struct sqlite3_file {
  571. const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
  572. };
  573. /*
  574. ** CAPI3REF: OS Interface File Virtual Methods Object {H11120} <S20110>
  575. **
  576. ** Every file opened by the [sqlite3_vfs] xOpen method populates an
  577. ** [sqlite3_file] object (or, more commonly, a subclass of the
  578. ** [sqlite3_file] object) with a pointer to an instance of this object.
  579. ** This object defines the methods used to perform various operations
  580. ** against the open file represented by the [sqlite3_file] object.
  581. **
  582. ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
  583. ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
  584. ** The second choice is a Mac OS-X style fullsync. The [SQLITE_SYNC_DATAONLY]
  585. ** flag may be ORed in to indicate that only the data of the file
  586. ** and not its inode needs to be synced.
  587. **
  588. ** The integer values to xLock() and xUnlock() are one of
  589. ** <ul>
  590. ** <li> [SQLITE_LOCK_NONE],
  591. ** <li> [SQLITE_LOCK_SHARED],
  592. ** <li> [SQLITE_LOCK_RESERVED],
  593. ** <li> [SQLITE_LOCK_PENDING], or
  594. ** <li> [SQLITE_LOCK_EXCLUSIVE].
  595. ** </ul>
  596. ** xLock() increases the lock. xUnlock() decreases the lock.
  597. ** The xCheckReservedLock() method checks whether any database connection,
  598. ** either in this process or in some other process, is holding a RESERVED,
  599. ** PENDING, or EXCLUSIVE lock on the file. It returns true
  600. ** if such a lock exists and false otherwise.
  601. **
  602. ** The xFileControl() method is a generic interface that allows custom
  603. ** VFS implementations to directly control an open file using the
  604. ** [sqlite3_file_control()] interface. The second "op" argument is an
  605. ** integer opcode. The third argument is a generic pointer intended to
  606. ** point to a structure that may contain arguments or space in which to
  607. ** write return values. Potential uses for xFileControl() might be
  608. ** functions to enable blocking locks with timeouts, to change the
  609. ** locking strategy (for example to use dot-file locks), to inquire
  610. ** about the status of a lock, or to break stale locks. The SQLite
  611. ** core reserves all opcodes less than 100 for its own use.
  612. ** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
  613. ** Applications that define a custom xFileControl method should use opcodes
  614. ** greater than 100 to avoid conflicts.
  615. **
  616. ** The xSectorSize() method returns the sector size of the
  617. ** device that underlies the file. The sector size is the
  618. ** minimum write that can be performed without disturbing
  619. ** other bytes in the file. The xDeviceCharacteristics()
  620. ** method returns a bit vector describing behaviors of the
  621. ** underlying device:
  622. **
  623. ** <ul>
  624. ** <li> [SQLITE_IOCAP_ATOMIC]
  625. ** <li> [SQLITE_IOCAP_ATOMIC512]
  626. ** <li> [SQLITE_IOCAP_ATOMIC1K]
  627. ** <li> [SQLITE_IOCAP_ATOMIC2K]
  628. ** <li> [SQLITE_IOCAP_ATOMIC4K]
  629. ** <li> [SQLITE_IOCAP_ATOMIC8K]
  630. ** <li> [SQLITE_IOCAP_ATOMIC16K]
  631. ** <li> [SQLITE_IOCAP_ATOMIC32K]
  632. ** <li> [SQLITE_IOCAP_ATOMIC64K]
  633. ** <li> [SQLITE_IOCAP_SAFE_APPEND]
  634. ** <li> [SQLITE_IOCAP_SEQUENTIAL]
  635. ** </ul>
  636. **
  637. ** The SQLITE_IOCAP_ATOMIC property means that all writes of
  638. ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
  639. ** mean that writes of blocks that are nnn bytes in size and
  640. ** are aligned to an address which is an integer multiple of
  641. ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
  642. ** that when data is appended to a file, the data is appended
  643. ** first then the size of the file is extended, never the other
  644. ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
  645. ** information is written to disk in the same order as calls
  646. ** to xWrite().
  647. */
  648. typedef struct sqlite3_io_methods sqlite3_io_methods;
  649. struct sqlite3_io_methods {
  650. int iVersion;
  651. int (*xClose)(sqlite3_file*);
  652. int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
  653. int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
  654. int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
  655. int (*xSync)(sqlite3_file*, int flags);
  656. int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
  657. int (*xLock)(sqlite3_file*, int);
  658. int (*xUnlock)(sqlite3_file*, int);
  659. int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
  660. int (*xFileControl)(sqlite3_file*, int op, void *pArg);
  661. int (*xSectorSize)(sqlite3_file*);
  662. int (*xDeviceCharacteristics)(sqlite3_file*);
  663. /* Additional methods may be added in future releases */
  664. };
  665. /*
  666. ** CAPI3REF: Standard File Control Opcodes {H11310} <S30800>
  667. **
  668. ** These integer constants are opcodes for the xFileControl method
  669. ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
  670. ** interface.
  671. **
  672. ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
  673. ** opcode causes the xFileControl method to write the current state of
  674. ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
  675. ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
  676. ** into an integer that the pArg argument points to. This capability
  677. ** is used during testing and only needs to be supported when SQLITE_TEST
  678. ** is defined.
  679. */
  680. #define SQLITE_FCNTL_LOCKSTATE 1
  681. /*
  682. ** CAPI3REF: Mutex Handle {H17110} <S20130>
  683. **
  684. ** The mutex module within SQLite defines [sqlite3_mutex] to be an
  685. ** abstract type for a mutex object. The SQLite core never looks
  686. ** at the internal representation of an [sqlite3_mutex]. It only
  687. ** deals with pointers to the [sqlite3_mutex] object.
  688. **
  689. ** Mutexes are created using [sqlite3_mutex_alloc()].
  690. */
  691. typedef struct sqlite3_mutex sqlite3_mutex;
  692. /*
  693. ** CAPI3REF: OS Interface Object {H11140} <S20100>
  694. **
  695. ** An instance of the sqlite3_vfs object defines the interface between
  696. ** the SQLite core and the underlying operating system. The "vfs"
  697. ** in the name of the object stands for "virtual file system".
  698. **
  699. ** The value of the iVersion field is initially 1 but may be larger in
  700. ** future versions of SQLite. Additional fields may be appended to this
  701. ** object when the iVersion value is increased. Note that the structure
  702. ** of the sqlite3_vfs object changes in the transaction between
  703. ** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
  704. ** modified.
  705. **
  706. ** The szOsFile field is the size of the subclassed [sqlite3_file]
  707. ** structure used by this VFS. mxPathname is the maximum length of
  708. ** a pathname in this VFS.
  709. **
  710. ** Registered sqlite3_vfs objects are kept on a linked list formed by
  711. ** the pNext pointer. The [sqlite3_vfs_register()]
  712. ** and [sqlite3_vfs_unregister()] interfaces manage this list
  713. ** in a thread-safe way. The [sqlite3_vfs_find()] interface
  714. ** searches the list. Neither the application code nor the VFS
  715. ** implementation should use the pNext pointer.
  716. **
  717. ** The pNext field is the only field in the sqlite3_vfs
  718. ** structure that SQLite will ever modify. SQLite will only access
  719. ** or modify this field while holding a particular static mutex.
  720. ** The application should never modify anything within the sqlite3_vfs
  721. ** object once the object has been registered.
  722. **
  723. ** The zName field holds the name of the VFS module. The name must
  724. ** be unique across all VFS modules.
  725. **
  726. ** {H11141} SQLite will guarantee that the zFilename parameter to xOpen
  727. ** is either a NULL pointer or string obtained
  728. ** from xFullPathname(). SQLite further guarantees that
  729. ** the string will be valid and unchanged until xClose() is
  730. ** called. {END} Because of the previous sentense,
  731. ** the [sqlite3_file] can safely store a pointer to the
  732. ** filename if it needs to remember the filename for some reason.
  733. ** If the zFilename parameter is xOpen is a NULL pointer then xOpen
  734. ** must invite its own temporary name for the file. Whenever the
  735. ** xFilename parameter is NULL it will also be the case that the
  736. ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
  737. **
  738. ** {H11142} The flags argument to xOpen() includes all bits set in
  739. ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
  740. ** or [sqlite3_open16()] is used, then flags includes at least
  741. ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. {END}
  742. ** If xOpen() opens a file read-only then it sets *pOutFlags to
  743. ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
  744. **
  745. ** {H11143} SQLite will also add one of the following flags to the xOpen()
  746. ** call, depending on the object being opened:
  747. **
  748. ** <ul>
  749. ** <li> [SQLITE_OPEN_MAIN_DB]
  750. ** <li> [SQLITE_OPEN_MAIN_JOURNAL]
  751. ** <li> [SQLITE_OPEN_TEMP_DB]
  752. ** <li> [SQLITE_OPEN_TEMP_JOURNAL]
  753. ** <li> [SQLITE_OPEN_TRANSIENT_DB]
  754. ** <li> [SQLITE_OPEN_SUBJOURNAL]
  755. ** <li> [SQLITE_OPEN_MASTER_JOURNAL]
  756. ** </ul> {END}
  757. **
  758. ** The file I/O implementation can use the object type flags to
  759. ** change the way it deals with files. For example, an application
  760. ** that does not care about crash recovery or rollback might make
  761. ** the open of a journal file a no-op. Writes to this journal would
  762. ** also be no-ops, and any attempt to read the journal would return
  763. ** SQLITE_IOERR. Or the implementation might recognize that a database
  764. ** file will be doing page-aligned sector reads and writes in a random
  765. ** order and set up its I/O subsystem accordingly.
  766. **
  767. ** SQLite might also add one of the following flags to the xOpen method:
  768. **
  769. ** <ul>
  770. ** <li> [SQLITE_OPEN_DELETEONCLOSE]
  771. ** <li> [SQLITE_OPEN_EXCLUSIVE]
  772. ** </ul>
  773. **
  774. ** {H11145} The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
  775. ** deleted when it is closed. {H11146} The [SQLITE_OPEN_DELETEONCLOSE]
  776. ** will be set for TEMP databases, journals and for subjournals.
  777. **
  778. ** {H11147} The [SQLITE_OPEN_EXCLUSIVE] flag means the file should be opened
  779. ** for exclusive access. This flag is set for all files except
  780. ** for the main database file.
  781. **
  782. ** {H11148} At least szOsFile bytes of memory are allocated by SQLite
  783. ** to hold the [sqlite3_file] structure passed as the third
  784. ** argument to xOpen. {END} The xOpen method does not have to
  785. ** allocate the structure; it should just fill it in.
  786. **
  787. ** {H11149} The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
  788. ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
  789. ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
  790. ** to test whether a file is at least readable. {END} The file can be a
  791. ** directory.
  792. **
  793. ** {H11150} SQLite will always allocate at least mxPathname+1 bytes for the
  794. ** output buffer xFullPathname. {H11151} The exact size of the output buffer
  795. ** is also passed as a parameter to both methods. {END} If the output buffer
  796. ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
  797. ** handled as a fatal error by SQLite, vfs implementations should endeavor
  798. ** to prevent this by setting mxPathname to a sufficiently large value.
  799. **
  800. ** The xRandomness(), xSleep(), and xCurrentTime() interfaces
  801. ** are not strictly a part of the filesystem, but they are
  802. ** included in the VFS structure for completeness.
  803. ** The xRandomness() function attempts to return nBytes bytes
  804. ** of good-quality randomness into zOut. The return value is
  805. ** the actual number of bytes of randomness obtained.
  806. ** The xSleep() method causes the calling thread to sleep for at
  807. ** least the number of microseconds given. The xCurrentTime()
  808. ** method returns a Julian Day Number for the current date and time.
  809. */
  810. typedef struct sqlite3_vfs sqlite3_vfs;
  811. struct sqlite3_vfs {
  812. int iVersion; /* Structure version number */
  813. int szOsFile; /* Size of subclassed sqlite3_file */
  814. int mxPathname; /* Maximum file pathname length */
  815. sqlite3_vfs *pNext; /* Next registered VFS */
  816. const char *zName; /* Name of this virtual file system */
  817. void *pAppData; /* Pointer to application-specific data */
  818. int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
  819. int flags, int *pOutFlags);
  820. int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
  821. int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
  822. int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
  823. void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
  824. void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
  825. void *(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol);
  826. void (*xDlClose)(sqlite3_vfs*, void*);
  827. int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
  828. int (*xSleep)(sqlite3_vfs*, int microseconds);
  829. int (*xCurrentTime)(sqlite3_vfs*, double*);
  830. int (*xGetLastError)(sqlite3_vfs*, int, char *);
  831. /* New fields may be appended in figure versions. The iVersion
  832. ** value will increment whenever this happens. */
  833. };
  834. /*
  835. ** CAPI3REF: Flags for the xAccess VFS method {H11190} <H11140>
  836. **
  837. ** {H11191} These integer constants can be used as the third parameter to
  838. ** the xAccess method of an [sqlite3_vfs] object. {END} They determine
  839. ** what kind of permissions the xAccess method is looking for.
  840. ** {H11192} With SQLITE_ACCESS_EXISTS, the xAccess method
  841. ** simply checks whether the file exists.
  842. ** {H11193} With SQLITE_ACCESS_READWRITE, the xAccess method
  843. ** checks whether the file is both readable and writable.
  844. ** {H11194} With SQLITE_ACCESS_READ, the xAccess method
  845. ** checks whether the file is readable.
  846. */
  847. #define SQLITE_ACCESS_EXISTS 0
  848. #define SQLITE_ACCESS_READWRITE 1
  849. #define SQLITE_ACCESS_READ 2
  850. /*
  851. ** CAPI3REF: Initialize The SQLite Library {H10130} <S20000><S30100>
  852. **
  853. ** The sqlite3_initialize() routine initializes the
  854. ** SQLite library. The sqlite3_shutdown() routine
  855. ** deallocates any resources that were allocated by sqlite3_initialize().
  856. **
  857. ** A call to sqlite3_initialize() is an "effective" call if it is
  858. ** the first time sqlite3_initialize() is invoked during the lifetime of
  859. ** the process, or if it is the first time sqlite3_initialize() is invoked
  860. ** following a call to sqlite3_shutdown(). Only an effective call
  861. ** of sqlite3_initialize() does any initialization. All other calls
  862. ** are harmless no-ops.
  863. **
  864. ** Among other things, sqlite3_initialize() shall invoke
  865. ** sqlite3_os_init(). Similarly, sqlite3_shutdown()
  866. ** shall invoke sqlite3_os_end().
  867. **
  868. ** The sqlite3_initialize() routine returns SQLITE_OK on success.
  869. ** If for some reason, sqlite3_initialize() is unable to initialize
  870. ** the library (perhaps it is unable to allocate a needed resource such
  871. ** as a mutex) it returns an [error code] other than SQLITE_OK.
  872. **
  873. ** The sqlite3_initialize() routine is called internally by many other
  874. ** SQLite interfaces so that an application usually does not need to
  875. ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
  876. ** calls sqlite3_initialize() so the SQLite library will be automatically
  877. ** initialized when [sqlite3_open()] is called if it has not be initialized
  878. ** already. However, if SQLite is compiled with the SQLITE_OMIT_AUTOINIT
  879. ** compile-time option, then the automatic calls to sqlite3_initialize()
  880. ** are omitted and the application must call sqlite3_initialize() directly
  881. ** prior to using any other SQLite interface. For maximum portability,
  882. ** it is recommended that applications always invoke sqlite3_initialize()
  883. ** directly prior to using any other SQLite interface. Future releases
  884. ** of SQLite may require this. In other words, the behavior exhibited
  885. ** when SQLite is compiled with SQLITE_OMIT_AUTOINIT might become the
  886. ** default behavior in some future release of SQLite.
  887. **
  888. ** The sqlite3_os_init() routine does operating-system specific
  889. ** initialization of the SQLite library. The sqlite3_os_end()
  890. ** routine undoes the effect of sqlite3_os_init(). Typical tasks
  891. ** performed by these routines include allocation or deallocation
  892. ** of static resources, initialization of global variables,
  893. ** setting up a default [sqlite3_vfs] module, or setting up
  894. ** a default configuration using [sqlite3_config()].
  895. **
  896. ** The application should never invoke either sqlite3_os_init()
  897. ** or sqlite3_os_end() directly. The application should only invoke
  898. ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
  899. ** interface is called automatically by sqlite3_initialize() and
  900. ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
  901. ** implementations for sqlite3_os_init() and sqlite3_os_end()
  902. ** are built into SQLite when it is compiled for unix, windows, or os/2.
  903. ** When built for other platforms (using the SQLITE_OS_OTHER=1 compile-time
  904. ** option) the application must supply a suitable implementation for
  905. ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
  906. ** implementation of sqlite3_os_init() or sqlite3_os_end()
  907. ** must return SQLITE_OK on success and some other [error code] upon
  908. ** failure.
  909. */
  910. int sqlite3_initialize(void);
  911. int sqlite3_shutdown(void);
  912. int sqlite3_os_init(void);
  913. int sqlite3_os_end(void);
  914. /*
  915. ** CAPI3REF: Configuring The SQLite Library {H10145} <S20000><S30200>
  916. ** EXPERIMENTAL
  917. **
  918. ** The sqlite3_config() interface is used to make global configuration
  919. ** changes to SQLite in order to tune SQLite to the specific needs of
  920. ** the application. The default configuration is recommended for most
  921. ** applications and so this routine is usually not necessary. It is
  922. ** provided to support rare applications with unusual needs.
  923. **
  924. ** The sqlite3_config() interface is not threadsafe. The application
  925. ** must insure that no other SQLite interfaces are invoked by other
  926. ** threads while sqlite3_config() is running. Furthermore, sqlite3_config()
  927. ** may only be invoked prior to library initialization using
  928. ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
  929. ** Note, however, that sqlite3_config() can be called as part of the
  930. ** implementation of an application-defined [sqlite3_os_init()].
  931. **
  932. ** The first argument to sqlite3_config() is an integer
  933. ** [SQLITE_CONFIG_SINGLETHREAD | configuration option] that determines
  934. ** what property of SQLite is to be configured. Subsequent arguments
  935. ** vary depending on the [SQLITE_CONFIG_SINGLETHREAD | configuration option]
  936. ** in the first argument.
  937. **
  938. ** When a configuration option is set, sqlite3_config() returns SQLITE_OK.
  939. ** If the option is unknown or SQLite is unable to set the option
  940. ** then this routine returns a non-zero [error code].
  941. */
  942. int sqlite3_config(int, ...);
  943. /*
  944. ** CAPI3REF: Configure database connections {H10180} <S20000>
  945. ** EXPERIMENTAL
  946. **
  947. ** The sqlite3_db_config() interface is used to make configuration
  948. ** changes to a [database connection]. The interface is similar to
  949. ** [sqlite3_config()] except that the changes apply to a single
  950. ** [database connection] (specified in the first argument). The
  951. ** sqlite3_db_config() interface can only be used immediately after
  952. ** the database connection is created using [sqlite3_open()],
  953. ** [sqlite3_open16()], or [sqlite3_open_v2()].
  954. **
  955. ** The second argument to sqlite3_db_config(D,V,...) is the
  956. ** configuration verb - an integer code that indicates what
  957. ** aspect of the [database connection] is being configured.
  958. ** The only choice for this value is [SQLITE_DBCONFIG_LOOKASIDE].
  959. ** New verbs are likely to be added in future releases of SQLite.
  960. ** Additional arguments depend on the verb.
  961. */
  962. int sqlite3_db_config(sqlite3*, int op, ...);
  963. /*
  964. ** CAPI3REF: Memory Allocation Routines {H10155} <S20120>
  965. ** EXPERIMENTAL
  966. **
  967. ** An instance of this object defines the interface between SQLite
  968. ** and low-level memory allocation routines.
  969. **
  970. ** This object is used in only one place in the SQLite interface.
  971. ** A pointer to an instance of this object is the argument to
  972. ** [sqlite3_config()] when the configuration option is
  973. ** [SQLITE_CONFIG_MALLOC]. By creating an instance of this object
  974. ** and passing it to [sqlite3_config()] during configuration, an
  975. ** application can specify an alternative memory allocation subsystem
  976. ** for SQLite to use for all of its dynamic memory needs.
  977. **
  978. ** Note that SQLite comes with a built-in memory allocator that is
  979. ** perfectly adequate for the overwhelming majority of applications
  980. ** and that this object is only useful to a tiny minority of applications
  981. ** with specialized memory allocation requirements. This object is
  982. ** also used during testing of SQLite in order to specify an alternative
  983. ** memory allocator that simulates memory out-of-memory conditions in
  984. ** order to verify that SQLite recovers gracefully from such
  985. ** conditions.
  986. **
  987. ** The xMalloc, xFree, and xRealloc methods must work like the
  988. ** malloc(), free(), and realloc() functions from the standard library.
  989. **
  990. ** xSize should return the allocated size of a memory allocation
  991. ** previously obtained from xMalloc or xRealloc. The allocated size
  992. ** is always at least as big as the requested size but may be larger.
  993. **
  994. ** The xRoundup method returns what would be the allocated size of
  995. ** a memory allocation given a particular requested size. Most memory
  996. ** allocators round up memory allocations at least to the next multiple
  997. ** of 8. Some allocators round up to a larger multiple or to a power of 2.
  998. **
  999. ** The xInit method initializes the memory allocator. (For example,
  1000. ** it might allocate any require mutexes or initialize internal data
  1001. ** structures. The xShutdown method is invoked (indirectly) by
  1002. ** [sqlite3_shutdown()] and should deallocate any resources acquired
  1003. ** by xInit. The pAppData pointer is used as the only parameter to
  1004. ** xInit and xShutdown.
  1005. */
  1006. typedef struct sqlite3_mem_methods sqlite3_mem_methods;
  1007. struct sqlite3_mem_methods {
  1008. void *(*xMalloc)(int); /* Memory allocation function */
  1009. void (*xFree)(void*); /* Free a prior allocation */
  1010. void *(*xRealloc)(void*,int); /* Resize an allocation */
  1011. int (*xSize)(void*); /* Return the size of an allocation */
  1012. int (*xRoundup)(int); /* Round up request size to allocation size */
  1013. int (*xInit)(void*); /* Initialize the memory allocator */
  1014. void (*xShutdown)(void*); /* Deinitialize the memory allocator */
  1015. void *pAppData; /* Argument to xInit() and xShutdown() */
  1016. };
  1017. /*
  1018. ** CAPI3REF: Configuration Options {H10160} <S20000>
  1019. ** EXPERIMENTAL
  1020. **
  1021. ** These constants are the available integer configuration options that
  1022. ** can be passed as the first argument to the [sqlite3_config()] interface.
  1023. **
  1024. ** New configuration options may be added in future releases of SQLite.
  1025. ** Existing configuration options might be discontinued. Applications
  1026. ** should check the return code from [sqlite3_config()] to make sure that
  1027. ** the call worked. The [sqlite3_config()] interface will return a
  1028. ** non-zero [error code] if a discontinued or unsupported configuration option
  1029. ** is invoked.
  1030. **
  1031. ** <dl>
  1032. ** <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
  1033. ** <dd>There are no arguments to this option. This option disables
  1034. ** all mutexing and puts SQLite into a mode where it can only be used
  1035. ** by a single thread.</dd>
  1036. **
  1037. ** <dt>SQLITE_CONFIG_MULTITHREAD</dt>
  1038. ** <dd>There are no arguments to this option. This option disables
  1039. ** mutexing on [database connection] and [prepared statement] objects.
  1040. ** The application is responsible for serializing access to
  1041. ** [database connections] and [prepared statements]. But other mutexes
  1042. ** are enabled so that SQLite will be safe to use in a multi-threaded
  1043. ** environment.</dd>
  1044. **
  1045. ** <dt>SQLITE_CONFIG_SERIALIZED</dt>
  1046. ** <dd>There are no arguments to this option. This option enables
  1047. ** all mutexes including the recursive
  1048. ** mutexes on [database connection] and [prepared statement] objects.
  1049. ** In this mode (which is the default when SQLite is compiled with
  1050. ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
  1051. ** to [database connections] and [prepared statements] so that the
  1052. ** application is free to use the same [database connection] or the
  1053. ** same [prepared statement] in different threads at the same time.
  1054. **
  1055. ** <p>This configuration option merely sets the default mutex
  1056. ** behavior to serialize access to [database connections]. Individual
  1057. ** [database connections] can override this setting
  1058. ** using the [SQLITE_OPEN_NOMUTEX] flag to [sqlite3_open_v2()].</p></dd>
  1059. **
  1060. ** <dt>SQLITE_CONFIG_MALLOC</dt>
  1061. ** <dd>This option takes a single argument which is a pointer to an
  1062. ** instance of the [sqlite3_mem_methods] structure. The argument specifies
  1063. ** alternative low-level memory allocation routines to be used in place of
  1064. ** the memory allocation routines built into SQLite.</dd>
  1065. **
  1066. ** <dt>SQLITE_CONFIG_GETMALLOC</dt>
  1067. ** <dd>This option takes a single argument which is a pointer to an
  1068. ** instance of the [sqlite3_mem_methods] structure. The [sqlite3_mem_methods]
  1069. ** structure is filled with the currently defined memory allocation routines.
  1070. ** This option can be used to overload the default memory allocation
  1071. ** routines with a wrapper that simulations memory allocation failure or
  1072. ** tracks memory usage, for example.</dd>
  1073. **
  1074. ** <dt>SQLITE_CONFIG_MEMSTATUS</dt>
  1075. ** <dd>This option takes single argument of type int, interpreted as a
  1076. ** boolean, which enables or disables the collection of memory allocation
  1077. ** statistics. When disabled, the following SQLite interfaces become
  1078. ** non-operational:
  1079. ** <ul>
  1080. ** <li> [sqlite3_memory_used()]
  1081. ** <li> [sqlite3_memory_highwater()]
  1082. ** <li> [sqlite3_soft_heap_limit()]
  1083. ** <li> [sqlite3_status()]
  1084. ** </ul>
  1085. ** </dd>
  1086. **
  1087. ** <dt>SQLITE_CONFIG_SCRATCH</dt>
  1088. ** <dd>This option specifies a static memory buffer that SQLite can use for
  1089. ** scratch memory. There are three arguments: A pointer to the memory, the
  1090. ** size of each scratch buffer (sz), and the number of buffers (N). The sz
  1091. ** argument must be a multiple of 16. The sz parameter should be a few bytes
  1092. ** larger than the actual scratch space required due internal overhead.
  1093. ** The first
  1094. ** argument should point to an allocation of at least sz*N bytes of memory.
  1095. ** SQLite will use no more than one scratch buffer at once per thread, so
  1096. ** N should be set to the expected maximum number of threads. The sz
  1097. ** parameter should be 6 times the size of the largest database page size.
  1098. ** Scratch buffers are used as part of the btree balance operation. If
  1099. ** The btree balancer needs additional memory beyond what is provided by
  1100. ** scratch buffers or if no scratch buffer space is specified, then SQLite
  1101. ** goes to [sqlite3_malloc()] to obtain the memory it needs.</dd>
  1102. **
  1103. ** <dt>SQLITE_CONFIG_PAGECACHE</dt>
  1104. ** <dd>This option specifies a static memory buffer that SQLite can use for
  1105. ** the database page cache. There are three arguments: A pointer to the
  1106. ** memory, the size of each page buffer (sz), and the number of pages (N).
  1107. ** The sz argument must be a power of two between 512 and 32768. The first
  1108. ** argument should point to an allocation of at least sz*N bytes of memory.
  1109. ** SQLite will use the memory provided by the first argument to satisfy its
  1110. ** memory needs for the first N pages that it adds to cache. If additional
  1111. ** page cache memory is needed beyond what is provided by this option, then
  1112. ** SQLite goes to [sqlite3_malloc()] for the additional storage space.
  1113. ** The implementation might use one or more of the N buffers to hold
  1114. ** memory accounting information. </dd>
  1115. **
  1116. ** <dt>SQLITE_CONFIG_HEAP</dt>
  1117. ** <dd>This option specifies a static memory buffer that SQLite will use
  1118. ** for all of its dynamic memory allocation needs beyond those provided
  1119. ** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
  1120. ** There are three arguments: A pointer to the memory, the number of
  1121. ** bytes in the memory buffer, and the minimum allocation size. If
  1122. ** the first pointer (the memory pointer) is NULL, then SQLite reverts
  1123. ** to using its default memory allocator (the system malloc() implementation),
  1124. ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. If the
  1125. ** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
  1126. ** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
  1127. ** allocator is engaged to handle all of SQLites memory allocation needs.</dd>
  1128. **
  1129. ** <dt>SQLITE_CONFIG_MUTEX</dt>
  1130. ** <dd>This option takes a single argument which is a pointer to an
  1131. ** instance of the [sqlite3_mutex_methods] structure. The argument specifies
  1132. ** alternative low-level mutex routines to be used in place
  1133. ** the mutex routines built into SQLite.</dd>
  1134. **
  1135. ** <dt>SQLITE_CONFIG_GETMUTEX</dt>
  1136. ** <dd>This option takes a single argument which is a pointer to an
  1137. ** instance of the [sqlite3_mutex_methods] structure. The
  1138. ** [sqlite3_mutex_methods]
  1139. ** structure is filled with the currently defined mutex routines.
  1140. ** This option can be used to overload the default mutex allocation
  1141. ** routines with a wrapper used to track mutex usage for performance
  1142. ** profiling or testing, for example.</dd>
  1143. **
  1144. ** <dt>SQLITE_CONFIG_LOOKASIDE</dt>
  1145. ** <dd>This option takes two arguments that determine the default
  1146. ** memory allcation lookaside optimization. The first argument is the
  1147. ** size of each lookaside buffer slot and the second is the number of
  1148. ** slots allocated to each database connection.</dd>
  1149. **
  1150. ** </dl>
  1151. */
  1152. #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
  1153. #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
  1154. #define SQLITE_CONFIG_SERIALIZED 3 /* nil */
  1155. #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
  1156. #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
  1157. #define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */
  1158. #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
  1159. #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
  1160. #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
  1161. #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
  1162. #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
  1163. #define SQLITE_CONFIG_CHUNKALLOC 12 /* int threshold */
  1164. #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
  1165. /*
  1166. ** CAPI3REF: Configuration Options {H10170} <S20000>
  1167. ** EXPERIMENTAL
  1168. **
  1169. ** These constants are the available integer configuration options that
  1170. ** can be passed as the second argument to the [sqlite3_db_config()] interface.
  1171. **
  1172. ** New configuration options may be added in future releases of SQLite.
  1173. ** Existing configuration options might be discontinued. Applications
  1174. ** should check the return code from [sqlite3_db_config()] to make sure that
  1175. ** the call worked. The [sqlite3_db_config()] interface will return a
  1176. ** non-zero [error code] if a discontinued or unsupported configuration option
  1177. ** is invoked.
  1178. **
  1179. ** <dl>
  1180. ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
  1181. ** <dd>This option takes three additional arguments that determine the
  1182. ** [lookaside memory allocator] configuration for the [database connection].
  1183. ** The first argument (the third parameter to [sqlite3_db_config()] is a
  1184. ** pointer to a memory buffer to use for lookaside memory. The first
  1185. ** argument may be NULL in which case SQLite will allocate the lookaside
  1186. ** buffer itself using [sqlite3_malloc()]. The second argument is the
  1187. ** size of each lookaside buffer slot and the third argument is the number of
  1188. ** slots. The size of the buffer in the first argument must be greater than
  1189. ** or equal to the product of the second and third arguments.</dd>
  1190. **
  1191. ** </dl>
  1192. */
  1193. #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
  1194. /*
  1195. ** CAPI3REF: Enable Or Disable Extended Result Codes {H12200} <S10700>
  1196. **
  1197. ** The sqlite3_extended_result_codes() routine enables or disables the
  1198. ** [extended result codes] feature of SQLite. The extended result
  1199. ** codes are disabled by default for historical compatibility considerations.
  1200. **
  1201. ** INVARIANTS:
  1202. **
  1203. ** {H12201} Each new [database connection] shall have the
  1204. ** [extended result codes] feature disabled by default.
  1205. **
  1206. ** {H12202} The [sqlite3_extended_result_codes(D,F)] interface shall enable
  1207. ** [extended result codes] for the [database connection] D
  1208. ** if the F parameter is true, or disable them if F is false.
  1209. */
  1210. int sqlite3_extended_result_codes(sqlite3*, int onoff);
  1211. /*
  1212. ** CAPI3REF: Last Insert Rowid {H12220} <S10700>
  1213. **
  1214. ** Each entry in an SQLite table has a unique 64-bit signed
  1215. ** integer key called the "rowid". The rowid is always available
  1216. ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
  1217. ** names are not also used by explicitly declared columns. If
  1218. ** the table has a column of type INTEGER PRIMARY KEY then that column
  1219. ** is another alias for the rowid.
  1220. **
  1221. ** This routine returns the rowid of the most recent
  1222. ** successful INSERT into the database from the [database connection]
  1223. ** in the first argument. If no successful INSERTs
  1224. ** have ever occurred on that database connection, zero is returned.
  1225. **
  1226. ** If an INSERT occurs within a trigger, then the rowid of the inserted
  1227. ** row is returned by this routine as long as the trigger is running.
  1228. ** But once the trigger terminates, the value returned by this routine
  1229. ** reverts to the last value inserted before the trigger fired.
  1230. **
  1231. ** An INSERT that fails due to a constraint violation is not a
  1232. ** successful INSERT and does not change the value returned by this
  1233. ** routine. Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
  1234. ** and INSERT OR ABORT make no changes to the return value of this
  1235. ** routine when their insertion fails. When INSERT OR REPLACE
  1236. ** encounters a constraint violation, it does not fail. The
  1237. ** INSERT continues to completion after deleting rows that caused
  1238. ** the constraint problem so INSERT OR REPLACE will always change
  1239. ** the return value of this interface.
  1240. **
  1241. ** For the purposes of this routine, an INSERT is considered to
  1242. ** be successful even if it is subsequently rolled back.
  1243. **
  1244. ** INVARIANTS:
  1245. **
  1246. ** {H12221} The [sqlite3_last_insert_rowid()] function returns the rowid
  1247. ** of the most recent successful INSERT performed on the same
  1248. ** [database connection] and within the same or higher level
  1249. ** trigger context, or zero if there have been no qualifying inserts.
  1250. **
  1251. ** {H12223} The [sqlite3_last_insert_rowid()] function returns the
  1252. ** same value when called from the same trigger context
  1253. ** immediately before and after a ROLLBACK.
  1254. **
  1255. ** ASSUMPTIONS:
  1256. **
  1257. ** {A12232} If a separate thread performs a new INSERT on the same
  1258. ** database connection while the [sqlite3_last_insert_rowid()]
  1259. ** function is running and thus changes the last insert rowid,
  1260. ** then the value returned by [sqlite3_last_insert_rowid()] is
  1261. ** unpredictable and might not equal either the old or the new
  1262. ** last insert rowid.
  1263. */
  1264. sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
  1265. /*
  1266. ** CAPI3REF: Count The Number Of Rows Modified {H12240} <S10600>
  1267. **
  1268. ** This function returns the number of database rows that were changed
  1269. ** or inserted or deleted by the most recently completed SQL statement
  1270. ** on the [database connection] specified by the first parameter.
  1271. ** Only changes that are directly specified by the INSERT, UPDATE,
  1272. ** or DELETE statement are counted. Auxiliary changes caused by
  1273. ** triggers are not counted. Use the [sqlite3_total_changes()] function
  1274. ** to find the total number of changes including changes caused by triggers.
  1275. **
  1276. ** A "row change" is a change to a single row of a single table
  1277. ** caused by an INSERT, DELETE, or UPDATE statement. Rows that
  1278. ** are changed as side effects of REPLACE constraint resolution,
  1279. ** rollback, ABORT processing, DROP TABLE, or by any other
  1280. ** mechanisms do not count as direct row changes.
  1281. **
  1282. ** A "trigger context" is a scope of execution that begins and
  1283. ** ends with the script of a trigger. Most SQL statements are
  1284. ** evaluated outside of any trigger. This is the "top level"
  1285. ** trigger context. If a trigger fires from the top level, a
  1286. ** new trigger context is entered for the duration of that one
  1287. ** trigger. Subtriggers create subcontexts for their duration.
  1288. **
  1289. ** Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
  1290. ** not create a new trigger context.
  1291. **
  1292. ** This function returns the number of direct row changes in the
  1293. ** most recent INSERT, UPDATE, or DELETE statement within the same
  1294. ** trigger context.
  1295. **
  1296. ** Thus, when called from the top level, this function returns the
  1297. ** number of changes in the most recent INSERT, UPDATE, or DELETE
  1298. ** that also occurred at the top level. Within the body of a trigger,
  1299. ** the sqlite3_changes() interface can be called to find the number of
  1300. ** changes in the most recently completed INSERT, UPDATE, or DELETE
  1301. ** statement within the body of the same trigger.
  1302. ** However, the number returned does not include changes
  1303. ** caused by subtriggers since those have their own context.
  1304. **
  1305. ** SQLite implements the command "DELETE FROM table" without a WHERE clause
  1306. ** by dropping and recreating the table. (This is much faster than going
  1307. ** through and deleting individual elements from the table.) Because of this
  1308. ** optimization, the deletions in "DELETE FROM table" are not row changes and
  1309. ** will not be counted by the sqlite3_changes() or [sqlite3_total_changes()]
  1310. ** functions, regardless of the number of elements that were originally
  1311. ** in the table. To get an accurate count of the number of rows deleted, use
  1312. ** "DELETE FROM table WHERE 1" instead.
  1313. **
  1314. ** INVARIANTS:
  1315. **
  1316. ** {H12241} The [sqlite3_changes()] function shall return the number of
  1317. ** row changes caused by the most recent INSERT, UPDATE,
  1318. ** or DELETE statement on the same database connection and
  1319. ** within the same or higher trigger context, or zero if there have
  1320. ** not been any qualifying row changes.
  1321. **
  1322. ** {H12243} Statements of the form "DELETE FROM tablename" with no
  1323. ** WHERE clause shall cause subsequent calls to
  1324. ** [sqlite3_changes()] to return zero, regardless of the
  1325. ** number of rows originally in the table.
  1326. **
  1327. ** ASSUMPTIONS:
  1328. **
  1329. ** {A12252} If a separate thread makes changes on the same database connection
  1330. ** while [sqlite3_changes()] is running then the value returned
  1331. ** is unpredictable and not meaningful.
  1332. */
  1333. int sqlite3_changes(sqlite3*);
  1334. /*
  1335. ** CAPI3REF: Total Number Of Rows Modified {H12260} <S10600>
  1336. **
  1337. ** This function returns the number of row changes caused by INSERT,
  1338. ** UPDATE or DELETE statements since the [database connection] was opened.
  1339. ** The count includes all changes from all trigger contexts. However,
  1340. ** the count does not include changes used to implement REPLACE constraints,
  1341. ** do rollbacks or ABORT processing, or DROP table processing.
  1342. ** The changes are counted as soon as the statement that makes them is
  1343. ** completed (when the statement handle is passed to [sqlite3_reset()] or
  1344. ** [sqlite3_finalize()]).
  1345. **
  1346. ** SQLite implements the command "DELETE FROM table" without a WHERE clause
  1347. ** by dropping and recreating the table. (This is much faster than going
  1348. ** through and deleting individual elements from the table.) Because of this
  1349. ** optimization, the deletions in "DELETE FROM table" are not row changes and
  1350. ** will not be counted by the sqlite3_changes() or [sqlite3_total_changes()]
  1351. ** functions, regardless of the number of elements that were originally
  1352. ** in the table. To get an accurate count of the number of rows deleted, use
  1353. ** "DELETE FROM table WHERE 1" instead.
  1354. **
  1355. ** See also the [sqlite3_changes()] interface.
  1356. **
  1357. ** INVARIANTS:
  1358. **
  1359. ** {H12261} The [sqlite3_total_changes()] returns the total number
  1360. ** of row changes caused by INSERT, UPDATE, and/or DELETE
  1361. ** statements on the same [database connection], in any
  1362. ** trigger context, since the database connection was created.
  1363. **
  1364. ** {H12263} Statements of the form "DELETE FROM tablename" with no
  1365. ** WHERE clause shall not change the value returned
  1366. ** by [sqlite3_total_changes()].
  1367. **
  1368. ** ASSUMPTIONS:
  1369. **
  1370. ** {A12264} If a separate thread makes changes on the same database connection
  1371. ** while [sqlite3_total_changes()] is running then the value
  1372. ** returned is unpredictable and not meaningful.
  1373. */
  1374. int sqlite3_total_changes(sqlite3*);
  1375. /*
  1376. ** CAPI3REF: Interrupt A Long-Running Query {H12270} <S30500>
  1377. **
  1378. ** This function causes any pending database operation to abort and
  1379. ** return at its earliest opportunity. This routine is typically
  1380. ** called in response to a user action such as pressing "Cancel"
  1381. ** or Ctrl-C where the user wants a long query operation to halt
  1382. ** immediately.
  1383. **
  1384. ** It is safe to call this routine from a thread different from the
  1385. ** thread that is currently running the database operation. But it
  1386. ** is not safe to call this routine with a [database connection] that
  1387. ** is closed or might close before sqlite3_interrupt() returns.
  1388. **
  1389. ** If an SQL operation is very nearly finished at the time when
  1390. ** sqlite3_interrupt() is called, then it might not have an opportunity
  1391. ** to be interrupted and might continue to completion.
  1392. **
  1393. ** An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
  1394. ** If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
  1395. ** that is inside an explicit transaction, then the entire transaction
  1396. ** will be rolled back automatically.
  1397. **
  1398. ** A call to sqlite3_interrupt() has no effect on SQL statements
  1399. ** that are started after sqlite3_interrupt() returns.
  1400. **
  1401. ** INVARIANTS:
  1402. **
  1403. ** {H12271} The [sqlite3_interrupt()] interface will force all running
  1404. ** SQL statements associated with the same database connection
  1405. ** to halt after processing at most one additional row of data.
  1406. **
  1407. ** {H12272} Any SQL statement that is interrupted by [sqlite3_interrupt()]
  1408. ** will return [SQLITE_INTERRUPT].
  1409. **
  1410. ** ASSUMPTIONS:
  1411. **
  1412. ** {A12279} If the database connection closes while [sqlite3_interrupt()]
  1413. ** is running then bad things will likely happen.
  1414. */
  1415. void sqlite3_interrupt(sqlite3*);
  1416. /*
  1417. ** CAPI3REF: Determine If An SQL Statement Is Complete {H10510} <S70200>
  1418. **
  1419. ** These routines are useful for command-line input to determine if the
  1420. ** currently entered text seems to form complete a SQL statement or
  1421. ** if additional input is needed before sending the text into
  1422. ** SQLite for parsing. These routines return true if the input string
  1423. ** appears to be a complete SQL statement. A statement is judged to be
  1424. ** complete if it ends with a semicolon token and is not a fragment of a
  1425. ** CREATE TRIGGER statement. Semicolons that are embedded within
  1426. ** string literals or quoted identifier names or comments are not
  1427. ** independent tokens (they are part of the token in which they are
  1428. ** embedded) and thus do not count as a statement terminator.
  1429. **
  1430. ** These routines do not parse the SQL statements thus
  1431. ** will not detect syntactically incorrect SQL.
  1432. **
  1433. ** INVARIANTS:
  1434. **
  1435. ** {H10511} A successful evaluation of [sqlite3_complete()] or
  1436. ** [sqlite3_complete16()] functions shall
  1437. ** return a numeric 1 if and only if the last non-whitespace
  1438. ** token in their input is a semicolon that is not in between
  1439. ** the BEGIN and END of a CREATE TRIGGER statement.
  1440. **
  1441. ** {H10512} If a memory allocation error occurs during an invocation
  1442. ** of [sqlite3_complete()] or [sqlite3_complete16()] then the
  1443. ** routine shall return [SQLITE_NOMEM].
  1444. **
  1445. ** ASSUMPTIONS:
  1446. **
  1447. ** {A10512} The input to [sqlite3_complete()] must be a zero-terminated
  1448. ** UTF-8 string.
  1449. **
  1450. ** {A10513} The input to [sqlite3_complete16()] must be a zero-terminated
  1451. ** UTF-16 string in native byte order.
  1452. */
  1453. int sqlite3_complete(const char *sql);
  1454. int sqlite3_complete16(const void *sql);
  1455. /*
  1456. ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors {H12310} <S40400>
  1457. **
  1458. ** This routine sets a callback function that might be invoked whenever
  1459. ** an attempt is made to open a database table that another thread
  1460. ** or process has locked.
  1461. **
  1462. ** If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
  1463. ** is returned immediately upon encountering the lock. If the busy callback
  1464. ** is not NULL, then the callback will be invoked with two arguments.
  1465. **
  1466. ** The first argument to the handler is a copy of the void* pointer which
  1467. ** is the third argument to sqlite3_busy_handler(). The second argument to
  1468. ** the handler callback is the number of times that the busy handler has
  1469. ** been invoked for this locking event. If the
  1470. ** busy callback returns 0, then no additional attempts are made to
  1471. ** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
  1472. ** If the callback returns non-zero, then another attempt
  1473. ** is made to open the database for reading and the cycle repeats.
  1474. **
  1475. ** The presence of a busy handler does not guarantee that it will be invoked
  1476. ** when there is lock contention. If SQLite determines that invoking the busy
  1477. ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
  1478. ** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler.
  1479. ** Consider a scenario where one process is holding a read lock that
  1480. ** it is trying to promote to a reserved lock and
  1481. ** a second process is holding a reserved lock that it is trying
  1482. ** to promote to an exclusive lock. The first process cannot proceed
  1483. ** because it is blocked by the second and the second process cannot
  1484. ** proceed because it is blocked by the first. If both processes
  1485. ** invoke the busy handlers, neither will make any progress. Therefore,
  1486. ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
  1487. ** will induce the first process to release its read lock and allow
  1488. ** the second process to proceed.
  1489. **
  1490. ** The default busy callback is NULL.
  1491. **
  1492. ** The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED]
  1493. ** when SQLite is in the middle of a large transaction where all the
  1494. ** changes will not fit into the in-memory cache. SQLite will
  1495. ** already hold a RESERVED lock on the database file, but it needs
  1496. ** to promote this lock to EXCLUSIVE so that it can spill cache
  1497. ** pages into the database file without harm to concurrent
  1498. ** readers. If it is unable to promote the lock, then the in-memory
  1499. ** cache will be left in an inconsistent state and so the error
  1500. ** code is promoted from the relatively benign [SQLITE_BUSY] to
  1501. ** the more severe [SQLITE_IOERR_BLOCKED]. This error code promotion
  1502. ** forces an automatic rollback of the changes. See the
  1503. ** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError">
  1504. ** CorruptionFollowingBusyError</a> wiki page for a discussion of why
  1505. ** this is important.
  1506. **
  1507. ** There can only be a single busy handler defined for each
  1508. ** [database connection]. Setting a new busy handler clears any
  1509. ** previously set handler. Note that calling [sqlite3_busy_timeout()]
  1510. ** will also set or clear the busy handler.
  1511. **
  1512. ** INVARIANTS:
  1513. **
  1514. ** {H12311} The [sqlite3_busy_handler(D,C,A)] function shall replace
  1515. ** busy callback in the [database connection] D with a new
  1516. ** a new busy handler C and application data pointer A.
  1517. **
  1518. ** {H12312} Newly created [database connections] shall have a busy
  1519. ** handler of NULL.
  1520. **
  1521. ** {H12314} When two or more [database connections] share a
  1522. ** [sqlite3_enable_shared_cache | common cache],
  1523. ** the busy handler for the database connection currently using
  1524. ** the cache shall be invoked when the cache encounters a lock.
  1525. **
  1526. ** {H12316} If a busy handler callback returns zero, then the SQLite interface
  1527. ** that provoked the locking event shall return [SQLITE_BUSY].
  1528. **
  1529. ** {H12318} SQLite shall invokes the busy handler with two arguments which
  1530. ** are a copy of the pointer supplied by the 3rd parameter to
  1531. ** [sqlite3_busy_handler()] and a count of the number of prior
  1532. ** invocations of the busy handler for the same locking event.
  1533. **
  1534. ** ASSUMPTIONS:
  1535. **
  1536. ** {A12319} A busy handler must not close the database connection
  1537. ** or [prepared statement] that invoked the busy handler.
  1538. */
  1539. int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
  1540. /*
  1541. ** CAPI3REF: Set A Busy Timeout {H12340} <S40410>
  1542. **
  1543. ** This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
  1544. ** for a specified amount of time when a table is locked. The handler
  1545. ** will sleep multiple times until at least "ms" milliseconds of sleeping
  1546. ** have accumulated. {H12343} After "ms" milliseconds of sleeping,
  1547. ** the handler returns 0 which causes [sqlite3_step()] to return
  1548. ** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
  1549. **
  1550. ** Calling this routine with an argument less than or equal to zero
  1551. ** turns off all busy handlers.
  1552. **
  1553. ** There can only be a single busy handler for a particular
  1554. ** [database connection] any any given moment. If another busy handler
  1555. ** was defined (using [sqlite3_busy_handler()]) prior to calling
  1556. ** this routine, that other busy handler is cleared.
  1557. **
  1558. ** INVARIANTS:
  1559. **
  1560. ** {H12341} The [sqlite3_busy_timeout()] function shall override any prior
  1561. ** [sqlite3_busy_timeout()] or [sqlite3_busy_handler()] setting
  1562. ** on the same [database connection].
  1563. **
  1564. ** {H12343} If the 2nd parameter to [sqlite3_busy_timeout()] is less than
  1565. ** or equal to zero, then the busy handler shall be cleared so that
  1566. ** all subsequent locking events immediately return [SQLITE_BUSY].
  1567. **
  1568. ** {H12344} If the 2nd parameter to [sqlite3_busy_timeout()] is a positive
  1569. ** number N, then a busy handler shall be set that repeatedly calls
  1570. ** the xSleep() method in the [sqlite3_vfs | VFS interface] until
  1571. ** either the lock clears or until the cumulative sleep time
  1572. ** reported back by xSleep() exceeds N milliseconds.
  1573. */
  1574. int sqlite3_busy_timeout(sqlite3*, int ms);
  1575. /*
  1576. ** CAPI3REF: Convenience Routines For Running Queries {H12370} <S10000>
  1577. **
  1578. ** Definition: A <b>result table</b> is memory data structure created by the
  1579. ** [sqlite3_get_table()] interface. A result table records the
  1580. ** complete query results from one or more queries.
  1581. **
  1582. ** The table conceptually has a number of rows and columns. But
  1583. ** these numbers are not part of the result table itself. These
  1584. ** numbers are obtained separately. Let N be the number of rows
  1585. ** and M be the number of columns.
  1586. **
  1587. ** A result table is an array of pointers to zero-terminated UTF-8 strings.
  1588. ** There are (N+1)*M elements in the array. The first M pointers point
  1589. ** to zero-terminated strings that contain the names of the columns.
  1590. ** The remaining entries all point to query results. NULL values result
  1591. ** in NULL pointers. All other values are in their UTF-8 zero-terminated
  1592. ** string representation as returned by [sqlite3_column_text()].
  1593. **
  1594. ** A result table might consist of one or more memory allocations.
  1595. ** It is not safe to pass a result table directly to [sqlite3_free()].
  1596. ** A result table should be deallocated using [sqlite3_free_table()].
  1597. **
  1598. ** As an example of the result table format, suppose a query result
  1599. ** is as follows:
  1600. **
  1601. ** <blockquote><pre>
  1602. ** Name | Age
  1603. ** -----------------------
  1604. ** Alice | 43
  1605. ** Bob | 28
  1606. ** Cindy | 21
  1607. ** </pre></blockquote>
  1608. **
  1609. ** There are two column (M==2) and three rows (N==3). Thus the
  1610. ** result table has 8 entries. Suppose the result table is stored
  1611. ** in an array names azResult. Then azResult holds this content:
  1612. **
  1613. ** <blockquote><pre>
  1614. ** azResult&#91;0] = "Name";
  1615. ** azResult&#91;1] = "Age";
  1616. ** azResult&#91;2] = "Alice";
  1617. ** azResult&#91;3] = "43";
  1618. ** azResult&#91;4] = "Bob";
  1619. ** azResult&#91;5] = "28";
  1620. ** azResult&#91;6] = "Cindy";
  1621. ** azResult&#91;7] = "21";
  1622. ** </pre></blockquote>
  1623. **
  1624. ** The sqlite3_get_table() function evaluates one or more
  1625. ** semicolon-separated SQL statements in the zero-terminated UTF-8
  1626. ** string of its 2nd parameter. It returns a result table to the
  1627. ** pointer given in its 3rd parameter.
  1628. **
  1629. ** After the calling function has finished using the result, it should
  1630. ** pass the pointer to the result table to sqlite3_free_table() in order to
  1631. ** release the memory that was malloced. Because of the way the
  1632. ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
  1633. ** function must not try to call [sqlite3_free()] directly. Only
  1634. ** [sqlite3_free_table()] is able to release the memory properly and safely.
  1635. **
  1636. ** The sqlite3_get_table() interface is implemented as a wrapper around
  1637. ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
  1638. ** to any internal data structures of SQLite. It uses only the public
  1639. ** interface defined here. As a consequence, errors that occur in the
  1640. ** wrapper layer outside of the internal [sqlite3_exec()] call are not
  1641. ** reflected in subsequent calls to [sqlite3_errcode()] or [sqlite3_errmsg()].
  1642. **
  1643. ** INVARIANTS:
  1644. **
  1645. ** {H12371} If a [sqlite3_get_table()] fails a memory allocation, then
  1646. ** it shall free the result table under construction, abort the
  1647. ** query in process, skip any subsequent queries, set the
  1648. ** *pazResult output pointer to NULL and return [SQLITE_NOMEM].
  1649. **
  1650. ** {H12373} If the pnColumn parameter to [sqlite3_get_table()] is not NULL
  1651. ** then a successful invocation of [sqlite3_get_table()] shall
  1652. ** write the number of columns in the
  1653. ** result set of the query into *pnColumn.
  1654. **
  1655. ** {H12374} If the pnRow parameter to [sqlite3_get_table()] is not NULL
  1656. ** then a successful invocation of [sqlite3_get_table()] shall
  1657. ** writes the number of rows in the
  1658. ** result set of the query into *pnRow.
  1659. **
  1660. ** {H12376} A successful invocation of [sqlite3_get_table()] that computes
  1661. ** N rows of result with C columns per row shall make *pazResult
  1662. ** point to an array of pointers to (N+1)*C strings where the first
  1663. ** C strings are column names as obtained from
  1664. ** [sqlite3_column_name()] and the rest are column result values
  1665. ** obtained from [sqlite3_column_text()].
  1666. **
  1667. ** {H12379} The values in the pazResult array returned by [sqlite3_get_table()]
  1668. ** shall remain valid until cleared by [sqlite3_free_table()].
  1669. **
  1670. ** {H12382} When an error occurs during evaluation of [sqlite3_get_table()]
  1671. ** the function shall set *pazResult to NULL, write an error message
  1672. ** into memory obtained from [sqlite3_malloc()], make
  1673. ** **pzErrmsg point to that error message, and return a
  1674. ** appropriate [error code].
  1675. */
  1676. int sqlite3_get_table(
  1677. sqlite3 *db, /* An open database */
  1678. const char *zSql, /* SQL to be evaluated */
  1679. char ***pazResult, /* Results of the query */
  1680. int *pnRow, /* Number of result rows written here */
  1681. int *pnColumn, /* Number of result columns written here */
  1682. char **pzErrmsg /* Error msg written here */
  1683. );
  1684. void sqlite3_free_table(char **result);
  1685. /*
  1686. ** CAPI3REF: Formatted String Printing Functions {H17400} <S70000><S20000>
  1687. **
  1688. ** These routines are workalikes of the "printf()" family of functions
  1689. ** from the standard C library.
  1690. **
  1691. ** The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
  1692. ** results into memory obtained from [sqlite3_malloc()].
  1693. ** The strings returned by these two routines should be
  1694. ** released by [sqlite3_free()]. Both routines return a
  1695. ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
  1696. ** memory to hold the resulting string.
  1697. **
  1698. ** In sqlite3_snprintf() routine is similar to "snprintf()" from
  1699. ** the standard C library. The result is written into the
  1700. ** buffer supplied as the second parameter whose size is given by
  1701. ** the first parameter. Note that the order of the
  1702. ** first two parameters is reversed from snprintf(). This is an
  1703. ** historical accident that cannot be fixed without breaking
  1704. ** backwards compatibility. Note also that sqlite3_snprintf()
  1705. ** returns a pointer to its buffer instead of the number of
  1706. ** characters actually written into the buffer. We admit that
  1707. ** the number of characters written would be a more useful return
  1708. ** value but we cannot change the implementation of sqlite3_snprintf()
  1709. ** now without breaking compatibility.
  1710. **
  1711. ** As long as the buffer size is greater than zero, sqlite3_snprintf()
  1712. ** guarantees that the buffer is always zero-terminated. The first
  1713. ** parameter "n" is the total size of the buffer, including space for
  1714. ** the zero terminator. So the longest string that can be completely
  1715. ** written will be n-1 characters.
  1716. **
  1717. ** These routines all implement some additional formatting
  1718. ** options that are useful for constructing SQL statements.
  1719. ** All of the usual printf() formatting options apply. In addition, there
  1720. ** is are "%q", "%Q", and "%z" options.
  1721. **
  1722. ** The %q option works like %s in that it substitutes a null-terminated
  1723. ** string from the argument list. But %q also doubles every '\'' character.
  1724. ** %q is designed for use inside a string literal. By doubling each '\''
  1725. ** character it escapes that character and allows it to be inserted into
  1726. ** the string.
  1727. **
  1728. ** For example, assume the string variable zText contains text as follows:
  1729. **
  1730. ** <blockquote><pre>
  1731. ** char *zText = "It's a happy day!";
  1732. ** </pre></blockquote>
  1733. **
  1734. ** One can use this text in an SQL statement as follows:
  1735. **
  1736. ** <blockquote><pre>
  1737. ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
  1738. ** sqlite3_exec(db, zSQL, 0, 0, 0);
  1739. ** sqlite3_free(zSQL);
  1740. ** </pre></blockquote>
  1741. **
  1742. ** Because the %q format string is used, the '\'' character in zText
  1743. ** is escaped and the SQL generated is as follows:
  1744. **
  1745. ** <blockquote><pre>
  1746. ** INSERT INTO table1 VALUES('It''s a happy day!')
  1747. ** </pre></blockquote>
  1748. **
  1749. ** This is correct. Had we used %s instead of %q, the generated SQL
  1750. ** would have looked like this:
  1751. **
  1752. ** <blockquote><pre>
  1753. ** INSERT INTO table1 VALUES('It's a happy day!');
  1754. ** </pre></blockquote>
  1755. **
  1756. ** This second example is an SQL syntax error. As a general rule you should
  1757. ** always use %q instead of %s when inserting text into a string literal.
  1758. **
  1759. ** The %Q option works like %q except it also adds single quotes around
  1760. ** the outside of the total string. Additionally, if the parameter in the
  1761. ** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
  1762. ** single quotes) in place of the %Q option. So, for example, one could say:
  1763. **
  1764. ** <blockquote><pre>
  1765. ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
  1766. ** sqlite3_exec(db, zSQL, 0, 0, 0);
  1767. ** sqlite3_free(zSQL);
  1768. ** </pre></blockquote>
  1769. **
  1770. ** The code above will render a correct SQL statement in the zSQL
  1771. ** variable even if the zText variable is a NULL pointer.
  1772. **
  1773. ** The "%z" formatting option works exactly like "%s" with the
  1774. ** addition that after the string has been read and copied into
  1775. ** the result, [sqlite3_free()] is called on the input string. {END}
  1776. **
  1777. ** INVARIANTS:
  1778. **
  1779. ** {H17403} The [sqlite3_mprintf()] and [sqlite3_vmprintf()] interfaces
  1780. ** return either pointers to zero-terminated UTF-8 strings held in
  1781. ** memory obtained from [sqlite3_malloc()] or NULL pointers if
  1782. ** a call to [sqlite3_malloc()] fails.
  1783. **
  1784. ** {H17406} The [sqlite3_snprintf()] interface writes a zero-terminated
  1785. ** UTF-8 string into the buffer pointed to by the second parameter
  1786. ** provided that the first parameter is greater than zero.
  1787. **
  1788. ** {H17407} The [sqlite3_snprintf()] interface does not write slots of
  1789. ** its output buffer (the second parameter) outside the range
  1790. ** of 0 through N-1 (where N is the first parameter)
  1791. ** regardless of the length of the string
  1792. ** requested by the format specification.
  1793. */
  1794. char *sqlite3_mprintf(const char*,...);
  1795. char *sqlite3_vmprintf(const char*, va_list);
  1796. char *sqlite3_snprintf(int,char*,const char*, ...);
  1797. /*
  1798. ** CAPI3REF: Memory Allocation Subsystem {H17300} <S20000>
  1799. **
  1800. ** The SQLite core uses these three routines for all of its own
  1801. ** internal memory allocation needs. "Core" in the previous sentence
  1802. ** does not include operating-system specific VFS implementation. The
  1803. ** Windows VFS uses native malloc() and free() for some operations.
  1804. **
  1805. ** The sqlite3_malloc() routine returns a pointer to a block
  1806. ** of memory at least N bytes in length, where N is the parameter.
  1807. ** If sqlite3_malloc() is unable to obtain sufficient free
  1808. ** memory, it returns a NULL pointer. If the parameter N to
  1809. ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
  1810. ** a NULL pointer.
  1811. **
  1812. ** Calling sqlite3_free() with a pointer previously returned
  1813. ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
  1814. ** that it might be reused. The sqlite3_free() routine is
  1815. ** a no-op if is called with a NULL pointer. Passing a NULL pointer
  1816. ** to sqlite3_free() is harmless. After being freed, memory
  1817. ** should neither be read nor written. Even reading previously freed
  1818. ** memory might result in a segmentation fault or other severe error.
  1819. ** Memory corruption, a segmentation fault, or other severe error
  1820. ** might result if sqlite3_free() is called with a non-NULL pointer that
  1821. ** was not obtained from sqlite3_malloc() or sqlite3_free().
  1822. **
  1823. ** The sqlite3_realloc() interface attempts to resize a
  1824. ** prior memory allocation to be at least N bytes, where N is the
  1825. ** second parameter. The memory allocation to be resized is the first
  1826. ** parameter. If the first parameter to sqlite3_realloc()
  1827. ** is a NULL pointer then its behavior is identical to calling
  1828. ** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
  1829. ** If the second parameter to sqlite3_realloc() is zero or
  1830. ** negative then the behavior is exactly the same as calling
  1831. ** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
  1832. ** sqlite3_realloc() returns a pointer to a memory allocation
  1833. ** of at least N bytes in size or NULL if sufficient memory is unavailable.
  1834. ** If M is the size of the prior allocation, then min(N,M) bytes
  1835. ** of the prior allocation are copied into the beginning of buffer returned
  1836. ** by sqlite3_realloc() and the prior allocation is freed.
  1837. ** If sqlite3_realloc() returns NULL, then the prior allocation
  1838. ** is not freed.
  1839. **
  1840. ** The memory returned by sqlite3_malloc() and sqlite3_realloc()
  1841. ** is always aligned to at least an 8 byte boundary. {END}
  1842. **
  1843. ** The default implementation of the memory allocation subsystem uses
  1844. ** the malloc(), realloc() and free() provided by the standard C library.
  1845. ** {H17382} However, if SQLite is compiled with the
  1846. ** SQLITE_MEMORY_SIZE=<i>NNN</i> C preprocessor macro (where <i>NNN</i>
  1847. ** is an integer), then SQLite create a static array of at least
  1848. ** <i>NNN</i> bytes in size and uses that array for all of its dynamic
  1849. ** memory allocation needs. {END} Additional memory allocator options
  1850. ** may be added in future releases.
  1851. **
  1852. ** In SQLite version 3.5.0 and 3.5.1, it was possible to define
  1853. ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
  1854. ** implementation of these routines to be omitted. That capability
  1855. ** is no longer provided. Only built-in memory allocators can be used.
  1856. **
  1857. ** The Windows OS interface layer calls
  1858. ** the system malloc() and free() directly when converting
  1859. ** filenames between the UTF-8 encoding used by SQLite
  1860. ** and whatever filename encoding is used by the particular Windows
  1861. ** installation. Memory allocation errors are detected, but
  1862. ** they are reported back as [SQLITE_CANTOPEN] or
  1863. ** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
  1864. **
  1865. ** INVARIANTS:
  1866. **
  1867. ** {H17303} The [sqlite3_malloc(N)] interface returns either a pointer to
  1868. ** a newly checked-out block of at least N bytes of memory
  1869. ** that is 8-byte aligned, or it returns NULL if it is unable
  1870. ** to fulfill the request.
  1871. **
  1872. ** {H17304} The [sqlite3_malloc(N)] interface returns a NULL pointer if
  1873. ** N is less than or equal to zero.
  1874. **
  1875. ** {H17305} The [sqlite3_free(P)] interface releases memory previously
  1876. ** returned from [sqlite3_malloc()] or [sqlite3_realloc()],
  1877. ** making it available for reuse.
  1878. **
  1879. ** {H17306} A call to [sqlite3_free(NULL)] is a harmless no-op.
  1880. **
  1881. ** {H17310} A call to [sqlite3_realloc(0,N)] is equivalent to a call
  1882. ** to [sqlite3_malloc(N)].
  1883. **
  1884. ** {H17312} A call to [sqlite3_realloc(P,0)] is equivalent to a call
  1885. ** to [sqlite3_free(P)].
  1886. **
  1887. ** {H17315} The SQLite core uses [sqlite3_malloc()], [sqlite3_realloc()],
  1888. ** and [sqlite3_free()] for all of its memory allocation and
  1889. ** deallocation needs.
  1890. **
  1891. ** {H17318} The [sqlite3_realloc(P,N)] interface returns either a pointer
  1892. ** to a block of checked-out memory of at least N bytes in size
  1893. ** that is 8-byte aligned, or a NULL pointer.
  1894. **
  1895. ** {H17321} When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first
  1896. ** copies the first K bytes of content from P into the newly
  1897. ** allocated block, where K is the lesser of N and the size of
  1898. ** the buffer P.
  1899. **
  1900. ** {H17322} When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first
  1901. ** releases the buffer P.
  1902. **
  1903. ** {H17323} When [sqlite3_realloc(P,N)] returns NULL, the buffer P is
  1904. ** not modified or released.
  1905. **
  1906. ** ASSUMPTIONS:
  1907. **
  1908. ** {A17350} The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
  1909. ** must be either NULL or else pointers obtained from a prior
  1910. ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
  1911. ** not yet been released.
  1912. **
  1913. ** {A17351} The application must not read or write any part of
  1914. ** a block of memory after it has been released using
  1915. ** [sqlite3_free()] or [sqlite3_realloc()].
  1916. */
  1917. void *sqlite3_malloc(int);
  1918. void *sqlite3_realloc(void*, int);
  1919. void sqlite3_free(void*);
  1920. /*
  1921. ** CAPI3REF: Memory Allocator Statistics {H17370} <S30210>
  1922. **
  1923. ** SQLite provides these two interfaces for reporting on the status
  1924. ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
  1925. ** routines, which form the built-in memory allocation subsystem.
  1926. **
  1927. ** INVARIANTS:
  1928. **
  1929. ** {H17371} The [sqlite3_memory_used()] routine returns the number of bytes
  1930. ** of memory currently outstanding (malloced but not freed).
  1931. **
  1932. ** {H17373} The [sqlite3_memory_highwater()] routine returns the maximum
  1933. ** value of [sqlite3_memory_used()] since the high-water mark
  1934. ** was last reset.
  1935. **
  1936. ** {H17374} The values returned by [sqlite3_memory_used()] and
  1937. ** [sqlite3_memory_highwater()] include any overhead
  1938. ** added by SQLite in its implementation of [sqlite3_malloc()],
  1939. ** but not overhead added by the any underlying system library
  1940. ** routines that [sqlite3_malloc()] may call.
  1941. **
  1942. ** {H17375} The memory high-water mark is reset to the current value of
  1943. ** [sqlite3_memory_used()] if and only if the parameter to
  1944. ** [sqlite3_memory_highwater()] is true. The value returned
  1945. ** by [sqlite3_memory_highwater(1)] is the high-water mark
  1946. ** prior to the reset.
  1947. */
  1948. sqlite3_int64 sqlite3_memory_used(void);
  1949. sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
  1950. /*
  1951. ** CAPI3REF: Pseudo-Random Number Generator {H17390} <S20000>
  1952. **
  1953. ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
  1954. ** select random ROWIDs when inserting new records into a table that
  1955. ** already uses the largest possible ROWID. The PRNG is also used for
  1956. ** the build-in random() and randomblob() SQL functions. This interface allows
  1957. ** applications to access the same PRNG for other purposes.
  1958. **
  1959. ** A call to this routine stores N bytes of randomness into buffer P.
  1960. **
  1961. ** The first time this routine is invoked (either internally or by
  1962. ** the application) the PRNG is seeded using randomness obtained
  1963. ** from the xRandomness method of the default [sqlite3_vfs] object.
  1964. ** On all subsequent invocations, the pseudo-randomness is generated
  1965. ** internally and without recourse to the [sqlite3_vfs] xRandomness
  1966. ** method.
  1967. **
  1968. ** INVARIANTS:
  1969. **
  1970. ** {H17392} The [sqlite3_randomness(N,P)] interface writes N bytes of
  1971. ** high-quality pseudo-randomness into buffer P.
  1972. */
  1973. void sqlite3_randomness(int N, void *P);
  1974. /*
  1975. ** CAPI3REF: Compile-Time Authorization Callbacks {H12500} <S70100>
  1976. **
  1977. ** This routine registers a authorizer callback with a particular
  1978. ** [database connection], supplied in the first argument.
  1979. ** The authorizer callback is invoked as SQL statements are being compiled
  1980. ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
  1981. ** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. At various
  1982. ** points during the compilation process, as logic is being created
  1983. ** to perform various actions, the authorizer callback is invoked to
  1984. ** see if those actions are allowed. The authorizer callback should
  1985. ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
  1986. ** specific action but allow the SQL statement to continue to be
  1987. ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
  1988. ** rejected with an error. If the authorizer callback returns
  1989. ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
  1990. ** then the [sqlite3_prepare_v2()] or equivalent call that triggered
  1991. ** the authorizer will fail with an error message.
  1992. **
  1993. ** When the callback returns [SQLITE_OK], that means the operation
  1994. ** requested is ok. When the callback returns [SQLITE_DENY], the
  1995. ** [sqlite3_prepare_v2()] or equivalent call that triggered the
  1996. ** authorizer will fail with an error message explaining that
  1997. ** access is denied. If the authorizer code is [SQLITE_READ]
  1998. ** and the callback returns [SQLITE_IGNORE] then the
  1999. ** [prepared statement] statement is constructed to substitute
  2000. ** a NULL value in place of the table column that would have
  2001. ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
  2002. ** return can be used to deny an untrusted user access to individual
  2003. ** columns of a table.
  2004. **
  2005. ** The first parameter to the authorizer callback is a copy of the third
  2006. ** parameter to the sqlite3_set_authorizer() interface. The second parameter
  2007. ** to the callback is an integer [SQLITE_COPY | action code] that specifies
  2008. ** the particular action to be authorized. The third through sixth parameters
  2009. ** to the callback are zero-terminated strings that contain additional
  2010. ** details about the action to be authorized.
  2011. **
  2012. ** An authorizer is used when [sqlite3_prepare | preparing]
  2013. ** SQL statements from an untrusted source, to ensure that the SQL statements
  2014. ** do not try to access data they are not allowed to see, or that they do not
  2015. ** try to execute malicious statements that damage the database. For
  2016. ** example, an application may allow a user to enter arbitrary
  2017. ** SQL queries for evaluation by a database. But the application does
  2018. ** not want the user to be able to make arbitrary changes to the
  2019. ** database. An authorizer could then be put in place while the
  2020. ** user-entered SQL is being [sqlite3_prepare | prepared] that
  2021. ** disallows everything except [SELECT] statements.
  2022. **
  2023. ** Applications that need to process SQL from untrusted sources
  2024. ** might also consider lowering resource limits using [sqlite3_limit()]
  2025. ** and limiting database size using the [max_page_count] [PRAGMA]
  2026. ** in addition to using an authorizer.
  2027. **
  2028. ** Only a single authorizer can be in place on a database connection
  2029. ** at a time. Each call to sqlite3_set_authorizer overrides the
  2030. ** previous call. Disable the authorizer by installing a NULL callback.
  2031. ** The authorizer is disabled by default.
  2032. **
  2033. ** Note that the authorizer callback is invoked only during
  2034. ** [sqlite3_prepare()] or its variants. Authorization is not
  2035. ** performed during statement evaluation in [sqlite3_step()].
  2036. **
  2037. ** INVARIANTS:
  2038. **
  2039. ** {H12501} The [sqlite3_set_authorizer(D,...)] interface registers a
  2040. ** authorizer callback with database connection D.
  2041. **
  2042. ** {H12502} The authorizer callback is invoked as SQL statements are
  2043. ** being compiled.
  2044. **
  2045. ** {H12503} If the authorizer callback returns any value other than
  2046. ** [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY], then
  2047. ** the [sqlite3_prepare_v2()] or equivalent call that caused
  2048. ** the authorizer callback to run shall fail with an
  2049. ** [SQLITE_ERROR] error code and an appropriate error message.
  2050. **
  2051. ** {H12504} When the authorizer callback returns [SQLITE_OK], the operation
  2052. ** described is processed normally.
  2053. **
  2054. ** {H12505} When the authorizer callback returns [SQLITE_DENY], the
  2055. ** [sqlite3_prepare_v2()] or equivalent call that caused the
  2056. ** authorizer callback to run shall fail
  2057. ** with an [SQLITE_ERROR] error code and an error message
  2058. ** explaining that access is denied.
  2059. **
  2060. ** {H12506} If the authorizer code (the 2nd parameter to the authorizer
  2061. ** callback) is [SQLITE_READ] and the authorizer callback returns
  2062. ** [SQLITE_IGNORE], then the prepared statement is constructed to
  2063. ** insert a NULL value in place of the table column that would have
  2064. ** been read if [SQLITE_OK] had been returned.
  2065. **
  2066. ** {H12507} If the authorizer code (the 2nd parameter to the authorizer
  2067. ** callback) is anything other than [SQLITE_READ], then
  2068. ** a return of [SQLITE_IGNORE] has the same effect as [SQLITE_DENY].
  2069. **
  2070. ** {H12510} The first parameter to the authorizer callback is a copy of
  2071. ** the third parameter to the [sqlite3_set_authorizer()] interface.
  2072. **
  2073. ** {H12511} The second parameter to the callback is an integer
  2074. ** [SQLITE_COPY | action code] that specifies the particular action
  2075. ** to be authorized.
  2076. **
  2077. ** {H12512} The third through sixth parameters to the callback are
  2078. ** zero-terminated strings that contain
  2079. ** additional details about the action to be authorized.
  2080. **
  2081. ** {H12520} Each call to [sqlite3_set_authorizer()] overrides
  2082. ** any previously installed authorizer.
  2083. **
  2084. ** {H12521} A NULL authorizer means that no authorization
  2085. ** callback is invoked.
  2086. **
  2087. ** {H12522} The default authorizer is NULL.
  2088. */
  2089. int sqlite3_set_authorizer(
  2090. sqlite3*,
  2091. int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
  2092. void *pUserData
  2093. );
  2094. /*
  2095. ** CAPI3REF: Authorizer Return Codes {H12590} <H12500>
  2096. **
  2097. ** The [sqlite3_set_authorizer | authorizer callback function] must
  2098. ** return either [SQLITE_OK] or one of these two constants in order
  2099. ** to signal SQLite whether or not the action is permitted. See the
  2100. ** [sqlite3_set_authorizer | authorizer documentation] for additional
  2101. ** information.
  2102. */
  2103. #define SQLITE_DENY 1 /* Abort the SQL statement with an error */
  2104. #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
  2105. /*
  2106. ** CAPI3REF: Authorizer Action Codes {H12550} <H12500>
  2107. **
  2108. ** The [sqlite3_set_authorizer()] interface registers a callback function
  2109. ** that is invoked to authorize certain SQL statement actions. The
  2110. ** second parameter to the callback is an integer code that specifies
  2111. ** what action is being authorized. These are the integer action codes that
  2112. ** the authorizer callback may be passed.
  2113. **
  2114. ** These action code values signify what kind of operation is to be
  2115. ** authorized. The 3rd and 4th parameters to the authorization
  2116. ** callback function will be parameters or NULL depending on which of these
  2117. ** codes is used as the second parameter. The 5th parameter to the
  2118. ** authorizer callback is the name of the database ("main", "temp",
  2119. ** etc.) if applicable. The 6th parameter to the authorizer callback
  2120. ** is the name of the inner-most trigger or view that is responsible for
  2121. ** the access attempt or NULL if this access attempt is directly from
  2122. ** top-level SQL code.
  2123. **
  2124. ** INVARIANTS:
  2125. **
  2126. ** {H12551} The second parameter to an
  2127. ** [sqlite3_set_authorizer | authorizer callback] is always an integer
  2128. ** [SQLITE_COPY | authorizer code] that specifies what action
  2129. ** is being authorized.
  2130. **
  2131. ** {H12552} The 3rd and 4th parameters to the
  2132. ** [sqlite3_set_authorizer | authorization callback]
  2133. ** will be parameters or NULL depending on which
  2134. ** [SQLITE_COPY | authorizer code] is used as the second parameter.
  2135. **
  2136. ** {H12553} The 5th parameter to the
  2137. ** [sqlite3_set_authorizer | authorizer callback] is the name
  2138. ** of the database (example: "main", "temp", etc.) if applicable.
  2139. **
  2140. ** {H12554} The 6th parameter to the
  2141. ** [sqlite3_set_authorizer | authorizer callback] is the name
  2142. ** of the inner-most trigger or view that is responsible for
  2143. ** the access attempt or NULL if this access attempt is directly from
  2144. ** top-level SQL code.
  2145. */
  2146. /******************************************* 3rd ************ 4th ***********/
  2147. #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
  2148. #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
  2149. #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
  2150. #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
  2151. #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
  2152. #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
  2153. #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
  2154. #define SQLITE_CREATE_VIEW 8 /* View Name NULL */
  2155. #define SQLITE_DELETE 9 /* Table Name NULL */
  2156. #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
  2157. #define SQLITE_DROP_TABLE 11 /* Table Name NULL */
  2158. #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
  2159. #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
  2160. #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
  2161. #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
  2162. #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
  2163. #define SQLITE_DROP_VIEW 17 /* View Name NULL */
  2164. #define SQLITE_INSERT 18 /* Table Name NULL */
  2165. #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
  2166. #define SQLITE_READ 20 /* Table Name Column Name */
  2167. #define SQLITE_SELECT 21 /* NULL NULL */
  2168. #define SQLITE_TRANSACTION 22 /* NULL NULL */
  2169. #define SQLITE_UPDATE 23 /* Table Name Column Name */
  2170. #define SQLITE_ATTACH 24 /* Filename NULL */
  2171. #define SQLITE_DETACH 25 /* Database Name NULL */
  2172. #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
  2173. #define SQLITE_REINDEX 27 /* Index Name NULL */
  2174. #define SQLITE_ANALYZE 28 /* Table Name NULL */
  2175. #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
  2176. #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
  2177. #define SQLITE_FUNCTION 31 /* Function Name NULL */
  2178. #define SQLITE_COPY 0 /* No longer used */
  2179. /*
  2180. ** CAPI3REF: Tracing And Profiling Functions {H12280} <S60400>
  2181. ** EXPERIMENTAL
  2182. **
  2183. ** These routines register callback functions that can be used for
  2184. ** tracing and profiling the execution of SQL statements.
  2185. **
  2186. ** The callback function registered by sqlite3_trace() is invoked at
  2187. ** various times when an SQL statement is being run by [sqlite3_step()].
  2188. ** The callback returns a UTF-8 rendering of the SQL statement text
  2189. ** as the statement first begins executing. Additional callbacks occur
  2190. ** as each triggered subprogram is entered. The callbacks for triggers
  2191. ** contain a UTF-8 SQL comment that identifies the trigger.
  2192. **
  2193. ** The callback function registered by sqlite3_profile() is invoked
  2194. ** as each SQL statement finishes. The profile callback contains
  2195. ** the original statement text and an estimate of wall-clock time
  2196. ** of how long that statement took to run.
  2197. **
  2198. ** INVARIANTS:
  2199. **
  2200. ** {H12281} The callback function registered by [sqlite3_trace()] is
  2201. ** whenever an SQL statement first begins to execute and
  2202. ** whenever a trigger subprogram first begins to run.
  2203. **
  2204. ** {H12282} Each call to [sqlite3_trace()] overrides the previously
  2205. ** registered trace callback.
  2206. **
  2207. ** {H12283} A NULL trace callback disables tracing.
  2208. **
  2209. ** {H12284} The first argument to the trace callback is a copy of
  2210. ** the pointer which was the 3rd argument to [sqlite3_trace()].
  2211. **
  2212. ** {H12285} The second argument to the trace callback is a
  2213. ** zero-terminated UTF-8 string containing the original text
  2214. ** of the SQL statement as it was passed into [sqlite3_prepare_v2()]
  2215. ** or the equivalent, or an SQL comment indicating the beginning
  2216. ** of a trigger subprogram.
  2217. **
  2218. ** {H12287} The callback function registered by [sqlite3_profile()] is invoked
  2219. ** as each SQL statement finishes.
  2220. **
  2221. ** {H12288} The first parameter to the profile callback is a copy of
  2222. ** the 3rd parameter to [sqlite3_profile()].
  2223. **
  2224. ** {H12289} The second parameter to the profile callback is a
  2225. ** zero-terminated UTF-8 string that contains the complete text of
  2226. ** the SQL statement as it was processed by [sqlite3_prepare_v2()]
  2227. ** or the equivalent.
  2228. **
  2229. ** {H12290} The third parameter to the profile callback is an estimate
  2230. ** of the number of nanoseconds of wall-clock time required to
  2231. ** run the SQL statement from start to finish.
  2232. */
  2233. void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
  2234. void *sqlite3_profile(sqlite3*,
  2235. void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
  2236. /*
  2237. ** CAPI3REF: Query Progress Callbacks {H12910} <S60400>
  2238. **
  2239. ** This routine configures a callback function - the
  2240. ** progress callback - that is invoked periodically during long
  2241. ** running calls to [sqlite3_exec()], [sqlite3_step()] and
  2242. ** [sqlite3_get_table()]. An example use for this
  2243. ** interface is to keep a GUI updated during a large query.
  2244. **
  2245. ** If the progress callback returns non-zero, the operation is
  2246. ** interrupted. This feature can be used to implement a
  2247. ** "Cancel" button on a GUI dialog box.
  2248. **
  2249. ** INVARIANTS:
  2250. **
  2251. ** {H12911} The callback function registered by sqlite3_progress_handler()
  2252. ** is invoked periodically during long running calls to
  2253. ** [sqlite3_step()].
  2254. **
  2255. ** {H12912} The progress callback is invoked once for every N virtual
  2256. ** machine opcodes, where N is the second argument to
  2257. ** the [sqlite3_progress_handler()] call that registered
  2258. ** the callback. If N is less than 1, sqlite3_progress_handler()
  2259. ** acts as if a NULL progress handler had been specified.
  2260. **
  2261. ** {H12913} The progress callback itself is identified by the third
  2262. ** argument to sqlite3_progress_handler().
  2263. **
  2264. ** {H12914} The fourth argument to sqlite3_progress_handler() is a
  2265. ** void pointer passed to the progress callback
  2266. ** function each time it is invoked.
  2267. **
  2268. ** {H12915} If a call to [sqlite3_step()] results in fewer than N opcodes
  2269. ** being executed, then the progress callback is never invoked.
  2270. **
  2271. ** {H12916} Every call to [sqlite3_progress_handler()]
  2272. ** overwrites any previously registered progress handler.
  2273. **
  2274. ** {H12917} If the progress handler callback is NULL then no progress
  2275. ** handler is invoked.
  2276. **
  2277. ** {H12918} If the progress callback returns a result other than 0, then
  2278. ** the behavior is a if [sqlite3_interrupt()] had been called.
  2279. ** <S30500>
  2280. */
  2281. void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
  2282. /*
  2283. ** CAPI3REF: Opening A New Database Connection {H12700} <S40200>
  2284. **
  2285. ** These routines open an SQLite database file whose name is given by the
  2286. ** filename argument. The filename argument is interpreted as UTF-8 for
  2287. ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
  2288. ** order for sqlite3_open16(). A [database connection] handle is usually
  2289. ** returned in *ppDb, even if an error occurs. The only exception is that
  2290. ** if SQLite is unable to allocate memory to hold the [sqlite3] object,
  2291. ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
  2292. ** object. If the database is opened (and/or created) successfully, then
  2293. ** [SQLITE_OK] is returned. Otherwise an [error code] is returned. The
  2294. ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
  2295. ** an English language description of the error.
  2296. **
  2297. ** The default encoding for the database will be UTF-8 if
  2298. ** sqlite3_open() or sqlite3_open_v2() is called and
  2299. ** UTF-16 in the native byte order if sqlite3_open16() is used.
  2300. **
  2301. ** Whether or not an error occurs when it is opened, resources
  2302. ** associated with the [database connection] handle should be released by
  2303. ** passing it to [sqlite3_close()] when it is no longer required.
  2304. **
  2305. ** The sqlite3_open_v2() interface works like sqlite3_open()
  2306. ** except that it accepts two additional parameters for additional control
  2307. ** over the new database connection. The flags parameter can take one of
  2308. ** the following three values, optionally combined with the
  2309. ** [SQLITE_OPEN_NOMUTEX] flag:
  2310. **
  2311. ** <dl>
  2312. ** <dt>[SQLITE_OPEN_READONLY]</dt>
  2313. ** <dd>The database is opened in read-only mode. If the database does not
  2314. ** already exist, an error is returned.</dd>
  2315. **
  2316. ** <dt>[SQLITE_OPEN_READWRITE]</dt>
  2317. ** <dd>The database is opened for reading and writing if possible, or reading
  2318. ** only if the file is write protected by the operating system. In either
  2319. ** case the database must already exist, otherwise an error is returned.</dd>
  2320. **
  2321. ** <dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
  2322. ** <dd>The database is opened for reading and writing, and is creates it if
  2323. ** it does not already exist. This is the behavior that is always used for
  2324. ** sqlite3_open() and sqlite3_open16().</dd>
  2325. ** </dl>
  2326. **
  2327. ** If the 3rd parameter to sqlite3_open_v2() is not one of the
  2328. ** combinations shown above or one of the combinations shown above combined
  2329. ** with the [SQLITE_OPEN_NOMUTEX] flag, then the behavior is undefined.
  2330. **
  2331. ** If the [SQLITE_OPEN_NOMUTEX] flag is set, then mutexes on the
  2332. ** opened [database connection] are disabled and the appliation must
  2333. ** insure that access to the [database connection] and its associated
  2334. ** [prepared statements] is serialized. The [SQLITE_OPEN_NOMUTEX] flag
  2335. ** is the default behavior is SQLite is configured using the
  2336. ** [SQLITE_CONFIG_MULTITHREAD] or [SQLITE_CONFIG_SINGLETHREAD] options
  2337. ** to [sqlite3_config()]. The [SQLITE_OPEN_NOMUTEX] flag only makes a
  2338. ** difference when SQLite is in its default [SQLITE_CONFIG_SERIALIZED] mode.
  2339. **
  2340. ** If the filename is ":memory:", then a private, temporary in-memory database
  2341. ** is created for the connection. This in-memory database will vanish when
  2342. ** the database connection is closed. Future versions of SQLite might
  2343. ** make use of additional special filenames that begin with the ":" character.
  2344. ** It is recommended that when a database filename actually does begin with
  2345. ** a ":" character you should prefix the filename with a pathname such as
  2346. ** "./" to avoid ambiguity.
  2347. **
  2348. ** If the filename is an empty string, then a private, temporary
  2349. ** on-disk database will be created. This private database will be
  2350. ** automatically deleted as soon as the database connection is closed.
  2351. **
  2352. ** The fourth parameter to sqlite3_open_v2() is the name of the
  2353. ** [sqlite3_vfs] object that defines the operating system interface that
  2354. ** the new database connection should use. If the fourth parameter is
  2355. ** a NULL pointer then the default [sqlite3_vfs] object is used.
  2356. **
  2357. ** <b>Note to Windows users:</b> The encoding used for the filename argument
  2358. ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
  2359. ** codepage is currently defined. Filenames containing international
  2360. ** characters must be converted to UTF-8 prior to passing them into
  2361. ** sqlite3_open() or sqlite3_open_v2().
  2362. **
  2363. ** INVARIANTS:
  2364. **
  2365. ** {H12701} The [sqlite3_open()], [sqlite3_open16()], and
  2366. ** [sqlite3_open_v2()] interfaces create a new
  2367. ** [database connection] associated with
  2368. ** the database file given in their first parameter.
  2369. **
  2370. ** {H12702} The filename argument is interpreted as UTF-8
  2371. ** for [sqlite3_open()] and [sqlite3_open_v2()] and as UTF-16
  2372. ** in the native byte order for [sqlite3_open16()].
  2373. **
  2374. ** {H12703} A successful invocation of [sqlite3_open()], [sqlite3_open16()],
  2375. ** or [sqlite3_open_v2()] writes a pointer to a new
  2376. ** [database connection] into *ppDb.
  2377. **
  2378. ** {H12704} The [sqlite3_open()], [sqlite3_open16()], and
  2379. ** [sqlite3_open_v2()] interfaces return [SQLITE_OK] upon success,
  2380. ** or an appropriate [error code] on failure.
  2381. **
  2382. ** {H12706} The default text encoding for a new database created using
  2383. ** [sqlite3_open()] or [sqlite3_open_v2()] will be UTF-8.
  2384. **
  2385. ** {H12707} The default text encoding for a new database created using
  2386. ** [sqlite3_open16()] will be UTF-16.
  2387. **
  2388. ** {H12709} The [sqlite3_open(F,D)] interface is equivalent to
  2389. ** [sqlite3_open_v2(F,D,G,0)] where the G parameter is
  2390. ** [SQLITE_OPEN_READWRITE]|[SQLITE_OPEN_CREATE].
  2391. **
  2392. ** {H12711} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
  2393. ** bit value [SQLITE_OPEN_READONLY] then the database is opened
  2394. ** for reading only.
  2395. **
  2396. ** {H12712} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the
  2397. ** bit value [SQLITE_OPEN_READWRITE] then the database is opened
  2398. ** reading and writing if possible, or for reading only if the
  2399. ** file is write protected by the operating system.
  2400. **
  2401. ** {H12713} If the G parameter to [sqlite3_open(v2(F,D,G,V)] omits the
  2402. ** bit value [SQLITE_OPEN_CREATE] and the database does not
  2403. ** previously exist, an error is returned.
  2404. **
  2405. ** {H12714} If the G parameter to [sqlite3_open(v2(F,D,G,V)] contains the
  2406. ** bit value [SQLITE_OPEN_CREATE] and the database does not
  2407. ** previously exist, then an attempt is made to create and
  2408. ** initialize the database.
  2409. **
  2410. ** {H12717} If the filename argument to [sqlite3_open()], [sqlite3_open16()],
  2411. ** or [sqlite3_open_v2()] is ":memory:", then an private,
  2412. ** ephemeral, in-memory database is created for the connection.
  2413. ** <todo>Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required
  2414. ** in sqlite3_open_v2()?</todo>
  2415. **
  2416. ** {H12719} If the filename is NULL or an empty string, then a private,
  2417. ** ephemeral on-disk database will be created.
  2418. ** <todo>Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required
  2419. ** in sqlite3_open_v2()?</todo>
  2420. **
  2421. ** {H12721} The [database connection] created by [sqlite3_open_v2(F,D,G,V)]
  2422. ** will use the [sqlite3_vfs] object identified by the V parameter,
  2423. ** or the default [sqlite3_vfs] object if V is a NULL pointer.
  2424. **
  2425. ** {H12723} Two [database connections] will share a common cache if both were
  2426. ** opened with the same VFS while [shared cache mode] was enabled and
  2427. ** if both filenames compare equal using memcmp() after having been
  2428. ** processed by the [sqlite3_vfs | xFullPathname] method of the VFS.
  2429. */
  2430. int sqlite3_open(
  2431. const char *filename, /* Database filename (UTF-8) */
  2432. sqlite3 **ppDb /* OUT: SQLite db handle */
  2433. );
  2434. int sqlite3_open16(
  2435. const void *filename, /* Database filename (UTF-16) */
  2436. sqlite3 **ppDb /* OUT: SQLite db handle */
  2437. );
  2438. int sqlite3_open_v2(
  2439. const char *filename, /* Database filename (UTF-8) */
  2440. sqlite3 **ppDb, /* OUT: SQLite db handle */
  2441. int flags, /* Flags */
  2442. const char *zVfs /* Name of VFS module to use */
  2443. );
  2444. /*
  2445. ** CAPI3REF: Error Codes And Messages {H12800} <S60200>
  2446. **
  2447. ** The sqlite3_errcode() interface returns the numeric [result code] or
  2448. ** [extended result code] for the most recent failed sqlite3_* API call
  2449. ** associated with a [database connection]. If a prior API call failed
  2450. ** but the most recent API call succeeded, the return value from
  2451. ** sqlite3_errcode() is undefined.
  2452. **
  2453. ** The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
  2454. ** text that describes the error, as either UTF-8 or UTF-16 respectively.
  2455. ** Memory to hold the error message string is managed internally.
  2456. ** The application does not need to worry about freeing the result.
  2457. ** However, the error string might be overwritten or deallocated by
  2458. ** subsequent calls to other SQLite interface functions.
  2459. **
  2460. ** If an interface fails with SQLITE_MISUSE, that means the interface
  2461. ** was invoked incorrectly by the application. In that case, the
  2462. ** error code and message may or may not be set.
  2463. **
  2464. ** INVARIANTS:
  2465. **
  2466. ** {H12801} The [sqlite3_errcode(D)] interface returns the numeric
  2467. ** [result code] or [extended result code] for the most recently
  2468. ** failed interface call associated with the [database connection] D.
  2469. **
  2470. ** {H12803} The [sqlite3_errmsg(D)] and [sqlite3_errmsg16(D)]
  2471. ** interfaces return English-language text that describes
  2472. ** the error in the mostly recently failed interface call,
  2473. ** encoded as either UTF-8 or UTF-16 respectively.
  2474. **
  2475. ** {H12807} The strings returned by [sqlite3_errmsg()] and [sqlite3_errmsg16()]
  2476. ** are valid until the next SQLite interface call.
  2477. **
  2478. ** {H12808} Calls to API routines that do not return an error code
  2479. ** (example: [sqlite3_data_count()]) do not
  2480. ** change the error code or message returned by
  2481. ** [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()].
  2482. **
  2483. ** {H12809} Interfaces that are not associated with a specific
  2484. ** [database connection] (examples:
  2485. ** [sqlite3_mprintf()] or [sqlite3_enable_shared_cache()]
  2486. ** do not change the values returned by
  2487. ** [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()].
  2488. */
  2489. int sqlite3_errcode(sqlite3 *db);
  2490. const char *sqlite3_errmsg(sqlite3*);
  2491. const void *sqlite3_errmsg16(sqlite3*);
  2492. /*
  2493. ** CAPI3REF: SQL Statement Object {H13000} <H13010>
  2494. ** KEYWORDS: {prepared statement} {prepared statements}
  2495. **
  2496. ** An instance of this object represents a single SQL statement.
  2497. ** This object is variously known as a "prepared statement" or a
  2498. ** "compiled SQL statement" or simply as a "statement".
  2499. **
  2500. ** The life of a statement object goes something like this:
  2501. **
  2502. ** <ol>
  2503. ** <li> Create the object using [sqlite3_prepare_v2()] or a related
  2504. ** function.
  2505. ** <li> Bind values to [host parameters] using the sqlite3_bind_*()
  2506. ** interfaces.
  2507. ** <li> Run the SQL by calling [sqlite3_step()] one or more times.
  2508. ** <li> Reset the statement using [sqlite3_reset()] then go back
  2509. ** to step 2. Do this zero or more times.
  2510. ** <li> Destroy the object using [sqlite3_finalize()].
  2511. ** </ol>
  2512. **
  2513. ** Refer to documentation on individual methods above for additional
  2514. ** information.
  2515. */
  2516. typedef struct sqlite3_stmt sqlite3_stmt;
  2517. /*
  2518. ** CAPI3REF: Run-time Limits {H12760} <S20600>
  2519. **
  2520. ** This interface allows the size of various constructs to be limited
  2521. ** on a connection by connection basis. The first parameter is the
  2522. ** [database connection] whose limit is to be set or queried. The
  2523. ** second parameter is one of the [limit categories] that define a
  2524. ** class of constructs to be size limited. The third parameter is the
  2525. ** new limit for that construct. The function returns the old limit.
  2526. **
  2527. ** If the new limit is a negative number, the limit is unchanged.
  2528. ** For the limit category of SQLITE_LIMIT_XYZ there is a hard upper
  2529. ** bound set by a compile-time C preprocessor macro named SQLITE_MAX_XYZ.
  2530. ** (The "_LIMIT_" in the name is changed to "_MAX_".)
  2531. ** Attempts to increase a limit above its hard upper bound are
  2532. ** silently truncated to the hard upper limit.
  2533. **
  2534. ** Run time limits are intended for use in applications that manage
  2535. ** both their own internal database and also databases that are controlled
  2536. ** by untrusted external sources. An example application might be a
  2537. ** webbrowser that has its own databases for storing history and
  2538. ** separate databases controlled by JavaScript applications downloaded
  2539. ** off the Internet. The internal databases can be given the
  2540. ** large, default limits. Databases managed by external sources can
  2541. ** be given much smaller limits designed to prevent a denial of service
  2542. ** attack. Developers might also want to use the [sqlite3_set_authorizer()]
  2543. ** interface to further control untrusted SQL. The size of the database
  2544. ** created by an untrusted script can be contained using the
  2545. ** [max_page_count] [PRAGMA].
  2546. **
  2547. ** New run-time limit categories may be added in future releases.
  2548. **
  2549. ** INVARIANTS:
  2550. **
  2551. ** {H12762} A successful call to [sqlite3_limit(D,C,V)] where V is
  2552. ** positive changes the limit on the size of construct C in the
  2553. ** [database connection] D to the lesser of V and the hard upper
  2554. ** bound on the size of C that is set at compile-time.
  2555. **
  2556. ** {H12766} A successful call to [sqlite3_limit(D,C,V)] where V is negative
  2557. ** leaves the state of the [database connection] D unchanged.
  2558. **
  2559. ** {H12769} A successful call to [sqlite3_limit(D,C,V)] returns the
  2560. ** value of the limit on the size of construct C in the
  2561. ** [database connection] D as it was prior to the call.
  2562. */
  2563. int sqlite3_limit(sqlite3*, int id, int newVal);
  2564. /*
  2565. ** CAPI3REF: Run-Time Limit Categories {H12790} <H12760>
  2566. ** KEYWORDS: {limit category} {limit categories}
  2567. **
  2568. ** These constants define various aspects of a [database connection]
  2569. ** that can be limited in size by calls to [sqlite3_limit()].
  2570. ** The meanings of the various limits are as follows:
  2571. **
  2572. ** <dl>
  2573. ** <dt>SQLITE_LIMIT_LENGTH</dt>
  2574. ** <dd>The maximum size of any string or BLOB or table row.<dd>
  2575. **
  2576. ** <dt>SQLITE_LIMIT_SQL_LENGTH</dt>
  2577. ** <dd>The maximum length of an SQL statement.</dd>
  2578. **
  2579. ** <dt>SQLITE_LIMIT_COLUMN</dt>
  2580. ** <dd>The maximum number of columns in a table definition or in the
  2581. ** result set of a SELECT or the maximum number of columns in an index
  2582. ** or in an ORDER BY or GROUP BY clause.</dd>
  2583. **
  2584. ** <dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
  2585. ** <dd>The maximum depth of the parse tree on any expression.</dd>
  2586. **
  2587. ** <dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
  2588. ** <dd>The maximum number of terms in a compound SELECT statement.</dd>
  2589. **
  2590. ** <dt>SQLITE_LIMIT_VDBE_OP</dt>
  2591. ** <dd>The maximum number of instructions in a virtual machine program
  2592. ** used to implement an SQL statement.</dd>
  2593. **
  2594. ** <dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
  2595. ** <dd>The maximum number of arguments on a function.</dd>
  2596. **
  2597. ** <dt>SQLITE_LIMIT_ATTACHED</dt>
  2598. ** <dd>The maximum number of attached databases.</dd>
  2599. **
  2600. ** <dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
  2601. ** <dd>The maximum length of the pattern argument to the LIKE or
  2602. ** GLOB operators.</dd>
  2603. **
  2604. ** <dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
  2605. ** <dd>The maximum number of variables in an SQL statement that can
  2606. ** be bound.</dd>
  2607. ** </dl>
  2608. */
  2609. #define SQLITE_LIMIT_LENGTH 0
  2610. #define SQLITE_LIMIT_SQL_LENGTH 1
  2611. #define SQLITE_LIMIT_COLUMN 2
  2612. #define SQLITE_LIMIT_EXPR_DEPTH 3
  2613. #define SQLITE_LIMIT_COMPOUND_SELECT 4
  2614. #define SQLITE_LIMIT_VDBE_OP 5
  2615. #define SQLITE_LIMIT_FUNCTION_ARG 6
  2616. #define SQLITE_LIMIT_ATTACHED 7
  2617. #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
  2618. #define SQLITE_LIMIT_VARIABLE_NUMBER 9
  2619. /*
  2620. ** CAPI3REF: Compiling An SQL Statement {H13010} <S10000>
  2621. ** KEYWORDS: {SQL statement compiler}
  2622. **
  2623. ** To execute an SQL query, it must first be compiled into a byte-code
  2624. ** program using one of these routines.
  2625. **
  2626. ** The first argument, "db", is a [database connection] obtained from a
  2627. ** prior call to [sqlite3_open()], [sqlite3_open_v2()] or [sqlite3_open16()].
  2628. **
  2629. ** The second argument, "zSql", is the statement to be compiled, encoded
  2630. ** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
  2631. ** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
  2632. ** use UTF-16.
  2633. **
  2634. ** If the nByte argument is less than zero, then zSql is read up to the
  2635. ** first zero terminator. If nByte is non-negative, then it is the maximum
  2636. ** number of bytes read from zSql. When nByte is non-negative, the
  2637. ** zSql string ends at either the first '\000' or '\u0000' character or
  2638. ** the nByte-th byte, whichever comes first. If the caller knows
  2639. ** that the supplied string is nul-terminated, then there is a small
  2640. ** performance advantage to be gained by passing an nByte parameter that
  2641. ** is equal to the number of bytes in the input string <i>including</i>
  2642. ** the nul-terminator bytes.
  2643. **
  2644. ** *pzTail is made to point to the first byte past the end of the
  2645. ** first SQL statement in zSql. These routines only compile the first
  2646. ** statement in zSql, so *pzTail is left pointing to what remains
  2647. ** uncompiled.
  2648. **
  2649. ** *ppStmt is left pointing to a compiled [prepared statement] that can be
  2650. ** executed using [sqlite3_step()]. If there is an error, *ppStmt is set
  2651. ** to NULL. If the input text contains no SQL (if the input is an empty
  2652. ** string or a comment) then *ppStmt is set to NULL.
  2653. ** {A13018} The calling procedure is responsible for deleting the compiled
  2654. ** SQL statement using [sqlite3_finalize()] after it has finished with it.
  2655. **
  2656. ** On success, [SQLITE_OK] is returned, otherwise an [error code] is returned.
  2657. **
  2658. ** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
  2659. ** recommended for all new programs. The two older interfaces are retained
  2660. ** for backwards compatibility, but their use is discouraged.
  2661. ** In the "v2" interfaces, the prepared statement
  2662. ** that is returned (the [sqlite3_stmt] object) contains a copy of the
  2663. ** original SQL text. This causes the [sqlite3_step()] interface to
  2664. ** behave a differently in two ways:
  2665. **
  2666. ** <ol>
  2667. ** <li>
  2668. ** If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
  2669. ** always used to do, [sqlite3_step()] will automatically recompile the SQL
  2670. ** statement and try to run it again. If the schema has changed in
  2671. ** a way that makes the statement no longer valid, [sqlite3_step()] will still
  2672. ** return [SQLITE_SCHEMA]. But unlike the legacy behavior, [SQLITE_SCHEMA] is
  2673. ** now a fatal error. Calling [sqlite3_prepare_v2()] again will not make the
  2674. ** error go away. Note: use [sqlite3_errmsg()] to find the text
  2675. ** of the parsing error that results in an [SQLITE_SCHEMA] return.
  2676. ** </li>
  2677. **
  2678. ** <li>
  2679. ** When an error occurs, [sqlite3_step()] will return one of the detailed
  2680. ** [error codes] or [extended error codes]. The legacy behavior was that
  2681. ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
  2682. ** and you would have to make a second call to [sqlite3_reset()] in order
  2683. ** to find the underlying cause of the problem. With the "v2" prepare
  2684. ** interfaces, the underlying reason for the error is returned immediately.
  2685. ** </li>
  2686. ** </ol>
  2687. **
  2688. ** INVARIANTS:
  2689. **
  2690. ** {H13011} The [sqlite3_prepare(db,zSql,...)] and
  2691. ** [sqlite3_prepare_v2(db,zSql,...)] interfaces interpret the
  2692. ** text in their zSql parameter as UTF-8.
  2693. **
  2694. ** {H13012} The [sqlite3_prepare16(db,zSql,...)] and
  2695. ** [sqlite3_prepare16_v2(db,zSql,...)] interfaces interpret the
  2696. ** text in their zSql parameter as UTF-16 in the native byte order.
  2697. **
  2698. ** {H13013} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)]
  2699. ** and its variants is less than zero, the SQL text is
  2700. ** read from zSql is read up to the first zero terminator.
  2701. **
  2702. ** {H13014} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)]
  2703. ** and its variants is non-negative, then at most nBytes bytes of
  2704. ** SQL text is read from zSql.
  2705. **
  2706. ** {H13015} In [sqlite3_prepare_v2(db,zSql,N,P,pzTail)] and its variants
  2707. ** if the zSql input text contains more than one SQL statement
  2708. ** and pzTail is not NULL, then *pzTail is made to point to the
  2709. ** first byte past the end of the first SQL statement in zSql.
  2710. ** <todo>What does *pzTail point to if there is one statement?</todo>
  2711. **
  2712. ** {H13016} A successful call to [sqlite3_prepare_v2(db,zSql,N,ppStmt,...)]
  2713. ** or one of its variants writes into *ppStmt a pointer to a new
  2714. ** [prepared statement] or a pointer to NULL if zSql contains
  2715. ** nothing other than whitespace or comments.
  2716. **
  2717. ** {H13019} The [sqlite3_prepare_v2()] interface and its variants return
  2718. ** [SQLITE_OK] or an appropriate [error code] upon failure.
  2719. **
  2720. ** {H13021} Before [sqlite3_prepare(db,zSql,nByte,ppStmt,pzTail)] or its
  2721. ** variants returns an error (any value other than [SQLITE_OK]),
  2722. ** they first set *ppStmt to NULL.
  2723. */
  2724. int sqlite3_prepare(
  2725. sqlite3 *db, /* Database handle */
  2726. const char *zSql, /* SQL statement, UTF-8 encoded */
  2727. int nByte, /* Maximum length of zSql in bytes. */
  2728. sqlite3_stmt **ppStmt, /* OUT: Statement handle */
  2729. const char **pzTail /* OUT: Pointer to unused portion of zSql */
  2730. );
  2731. int sqlite3_prepare_v2(
  2732. sqlite3 *db, /* Database handle */
  2733. const char *zSql, /* SQL statement, UTF-8 encoded */
  2734. int nByte, /* Maximum length of zSql in bytes. */
  2735. sqlite3_stmt **ppStmt, /* OUT: Statement handle */
  2736. const char **pzTail /* OUT: Pointer to unused portion of zSql */
  2737. );
  2738. int sqlite3_prepare16(
  2739. sqlite3 *db, /* Database handle */
  2740. const void *zSql, /* SQL statement, UTF-16 encoded */
  2741. int nByte, /* Maximum length of zSql in bytes. */
  2742. sqlite3_stmt **ppStmt, /* OUT: Statement handle */
  2743. const void **pzTail /* OUT: Pointer to unused portion of zSql */
  2744. );
  2745. int sqlite3_prepare16_v2(
  2746. sqlite3 *db, /* Database handle */
  2747. const void *zSql, /* SQL statement, UTF-16 encoded */
  2748. int nByte, /* Maximum length of zSql in bytes. */
  2749. sqlite3_stmt **ppStmt, /* OUT: Statement handle */
  2750. const void **pzTail /* OUT: Pointer to unused portion of zSql */
  2751. );
  2752. /*
  2753. ** CAPIREF: Retrieving Statement SQL {H13100} <H13000>
  2754. **
  2755. ** This interface can be used to retrieve a saved copy of the original
  2756. ** SQL text used to create a [prepared statement] if that statement was
  2757. ** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
  2758. **
  2759. ** INVARIANTS:
  2760. **
  2761. ** {H13101} If the [prepared statement] passed as the argument to
  2762. ** [sqlite3_sql()] was compiled using either [sqlite3_prepare_v2()] or
  2763. ** [sqlite3_prepare16_v2()], then [sqlite3_sql()] returns
  2764. ** a pointer to a zero-terminated string containing a UTF-8 rendering
  2765. ** of the original SQL statement.
  2766. **
  2767. ** {H13102} If the [prepared statement] passed as the argument to
  2768. ** [sqlite3_sql()] was compiled using either [sqlite3_prepare()] or
  2769. ** [sqlite3_prepare16()], then [sqlite3_sql()] returns a NULL pointer.
  2770. **
  2771. ** {H13103} The string returned by [sqlite3_sql(S)] is valid until the
  2772. ** [prepared statement] S is deleted using [sqlite3_finalize(S)].
  2773. */
  2774. const char *sqlite3_sql(sqlite3_stmt *pStmt);
  2775. /*
  2776. ** CAPI3REF: Dynamically Typed Value Object {H15000} <S20200>
  2777. ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
  2778. **
  2779. ** SQLite uses the sqlite3_value object to represent all values
  2780. ** that can be stored in a database table. SQLite uses dynamic typing
  2781. ** for the values it stores. Values stored in sqlite3_value objects
  2782. ** can be integers, floating point values, strings, BLOBs, or NULL.
  2783. **
  2784. ** An sqlite3_value object may be either "protected" or "unprotected".
  2785. ** Some interfaces require a protected sqlite3_value. Other interfaces
  2786. ** will accept either a protected or an unprotected sqlite3_value.
  2787. ** Every interface that accepts sqlite3_value arguments specifies
  2788. ** whether or not it requires a protected sqlite3_value.
  2789. **
  2790. ** The terms "protected" and "unprotected" refer to whether or not
  2791. ** a mutex is held. A internal mutex is held for a protected
  2792. ** sqlite3_value object but no mutex is held for an unprotected
  2793. ** sqlite3_value object. If SQLite is compiled to be single-threaded
  2794. ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
  2795. ** or if SQLite is run in one of reduced mutex modes
  2796. ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
  2797. ** then there is no distinction between protected and unprotected
  2798. ** sqlite3_value objects and they can be used interchangeably. However,
  2799. ** for maximum code portability it is recommended that applications
  2800. ** still make the distinction between between protected and unprotected
  2801. ** sqlite3_value objects even when not strictly required.
  2802. **
  2803. ** The sqlite3_value objects that are passed as parameters into the
  2804. ** implementation of [application-defined SQL functions] are protected.
  2805. ** The sqlite3_value object returned by
  2806. ** [sqlite3_column_value()] is unprotected.
  2807. ** Unprotected sqlite3_value objects may only be used with
  2808. ** [sqlite3_result_value()] and [sqlite3_bind_value()].
  2809. ** The [sqlite3_value_blob | sqlite3_value_type()] family of
  2810. ** interfaces require protected sqlite3_value objects.
  2811. */
  2812. typedef struct Mem sqlite3_value;
  2813. /*
  2814. ** CAPI3REF: SQL Function Context Object {H16001} <S20200>
  2815. **
  2816. ** The context in which an SQL function executes is stored in an
  2817. ** sqlite3_context object. A pointer to an sqlite3_context object
  2818. ** is always first parameter to [application-defined SQL functions].
  2819. ** The application-defined SQL function implementation will pass this
  2820. ** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
  2821. ** [sqlite3_aggregate_context()], [sqlite3_user_data()],
  2822. ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
  2823. ** and/or [sqlite3_set_auxdata()].
  2824. */
  2825. typedef struct sqlite3_context sqlite3_context;
  2826. /*
  2827. ** CAPI3REF: Binding Values To Prepared Statements {H13500} <S70300>
  2828. ** KEYWORDS: {host parameter} {host parameters} {host parameter name}
  2829. ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
  2830. **
  2831. ** In the SQL strings input to [sqlite3_prepare_v2()] and its variants,
  2832. ** literals may be replaced by a parameter in one of these forms:
  2833. **
  2834. ** <ul>
  2835. ** <li> ?
  2836. ** <li> ?NNN
  2837. ** <li> :VVV
  2838. ** <li> @VVV
  2839. ** <li> $VVV
  2840. ** </ul>
  2841. **
  2842. ** In the parameter forms shown above NNN is an integer literal,
  2843. ** and VVV is an alpha-numeric parameter name. The values of these
  2844. ** parameters (also called "host parameter names" or "SQL parameters")
  2845. ** can be set using the sqlite3_bind_*() routines defined here.
  2846. **
  2847. ** The first argument to the sqlite3_bind_*() routines is always
  2848. ** a pointer to the [sqlite3_stmt] object returned from
  2849. ** [sqlite3_prepare_v2()] or its variants.
  2850. **
  2851. ** The second argument is the index of the SQL parameter to be set.
  2852. ** The leftmost SQL parameter has an index of 1. When the same named
  2853. ** SQL parameter is used more than once, second and subsequent
  2854. ** occurrences have the same index as the first occurrence.
  2855. ** The index for named parameters can be looked up using the
  2856. ** [sqlite3_bind_parameter_index()] API if desired. The index
  2857. ** for "?NNN" parameters is the value of NNN.
  2858. ** The NNN value must be between 1 and the [sqlite3_limit()]
  2859. ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
  2860. **
  2861. ** The third argument is the value to bind to the parameter.
  2862. **
  2863. ** In those routines that have a fourth argument, its value is the
  2864. ** number of bytes in the parameter. To be clear: the value is the
  2865. ** number of <u>bytes</u> in the value, not the number of characters.
  2866. ** If the fourth parameter is negative, the length of the string is
  2867. ** the number of bytes up to the first zero terminator.
  2868. **
  2869. ** The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
  2870. ** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
  2871. ** string after SQLite has finished with it. If the fifth argument is
  2872. ** the special value [SQLITE_STATIC], then SQLite assumes that the
  2873. ** information is in static, unmanaged space and does not need to be freed.
  2874. ** If the fifth argument has the value [SQLITE_TRANSIENT], then
  2875. ** SQLite makes its own private copy of the data immediately, before
  2876. ** the sqlite3_bind_*() routine returns.
  2877. **
  2878. ** The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
  2879. ** is filled with zeroes. A zeroblob uses a fixed amount of memory
  2880. ** (just an integer to hold its size) while it is being processed.
  2881. ** Zeroblobs are intended to serve as placeholders for BLOBs whose
  2882. ** content is later written using
  2883. ** [sqlite3_blob_open | incremental BLOB I/O] routines.
  2884. ** A negative value for the zeroblob results in a zero-length BLOB.
  2885. **
  2886. ** The sqlite3_bind_*() routines must be called after
  2887. ** [sqlite3_prepare_v2()] (and its variants) or [sqlite3_reset()] and
  2888. ** before [sqlite3_step()].
  2889. ** Bindings are not cleared by the [sqlite3_reset()] routine.
  2890. ** Unbound parameters are interpreted as NULL.
  2891. **
  2892. ** These routines return [SQLITE_OK] on success or an error code if
  2893. ** anything goes wrong. [SQLITE_RANGE] is returned if the parameter
  2894. ** index is out of range. [SQLITE_NOMEM] is returned if malloc() fails.
  2895. ** [SQLITE_MISUSE] might be returned if these routines are called on a
  2896. ** virtual machine that is the wrong state or which has already been finalized.
  2897. ** Detection of misuse is unreliable. Applications should not depend
  2898. ** on SQLITE_MISUSE returns. SQLITE_MISUSE is intended to indicate a
  2899. ** a logic error in the application. Future versions of SQLite might
  2900. ** panic rather than return SQLITE_MISUSE.
  2901. **
  2902. ** See also: [sqlite3_bind_parameter_count()],
  2903. ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
  2904. **
  2905. ** INVARIANTS:
  2906. **
  2907. ** {H13506} The [SQL statement compiler] recognizes tokens of the forms
  2908. ** "?", "?NNN", "$VVV", ":VVV", and "@VVV" as SQL parameters,
  2909. ** where NNN is any sequence of one or more digits
  2910. ** and where VVV is any sequence of one or more alphanumeric
  2911. ** characters or "::" optionally followed by a string containing
  2912. ** no spaces and contained within parentheses.
  2913. **
  2914. ** {H13509} The initial value of an SQL parameter is NULL.
  2915. **
  2916. ** {H13512} The index of an "?" SQL parameter is one larger than the
  2917. ** largest index of SQL parameter to the left, or 1 if
  2918. ** the "?" is the leftmost SQL parameter.
  2919. **
  2920. ** {H13515} The index of an "?NNN" SQL parameter is the integer NNN.
  2921. **
  2922. ** {H13518} The index of an ":VVV", "$VVV", or "@VVV" SQL parameter is
  2923. ** the same as the index of leftmost occurrences of the same
  2924. ** parameter, or one more than the largest index over all
  2925. ** parameters to the left if this is the first occurrence
  2926. ** of this parameter, or 1 if this is the leftmost parameter.
  2927. **
  2928. ** {H13521} The [SQL statement compiler] fails with an [SQLITE_RANGE]
  2929. ** error if the index of an SQL parameter is less than 1
  2930. ** or greater than the compile-time SQLITE_MAX_VARIABLE_NUMBER
  2931. ** parameter.
  2932. **
  2933. ** {H13524} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,V,...)]
  2934. ** associate the value V with all SQL parameters having an
  2935. ** index of N in the [prepared statement] S.
  2936. **
  2937. ** {H13527} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,...)]
  2938. ** override prior calls with the same values of S and N.
  2939. **
  2940. ** {H13530} Bindings established by [sqlite3_bind_text | sqlite3_bind(S,...)]
  2941. ** persist across calls to [sqlite3_reset(S)].
  2942. **
  2943. ** {H13533} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
  2944. ** [sqlite3_bind_text(S,N,V,L,D)], or
  2945. ** [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds the first L
  2946. ** bytes of the BLOB or string pointed to by V, when L
  2947. ** is non-negative.
  2948. **
  2949. ** {H13536} In calls to [sqlite3_bind_text(S,N,V,L,D)] or
  2950. ** [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds characters
  2951. ** from V through the first zero character when L is negative.
  2952. **
  2953. ** {H13539} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
  2954. ** [sqlite3_bind_text(S,N,V,L,D)], or
  2955. ** [sqlite3_bind_text16(S,N,V,L,D)] when D is the special
  2956. ** constant [SQLITE_STATIC], SQLite assumes that the value V
  2957. ** is held in static unmanaged space that will not change
  2958. ** during the lifetime of the binding.
  2959. **
  2960. ** {H13542} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
  2961. ** [sqlite3_bind_text(S,N,V,L,D)], or
  2962. ** [sqlite3_bind_text16(S,N,V,L,D)] when D is the special
  2963. ** constant [SQLITE_TRANSIENT], the routine makes a
  2964. ** private copy of the value V before it returns.
  2965. **
  2966. ** {H13545} In calls to [sqlite3_bind_blob(S,N,V,L,D)],
  2967. ** [sqlite3_bind_text(S,N,V,L,D)], or
  2968. ** [sqlite3_bind_text16(S,N,V,L,D)] when D is a pointer to
  2969. ** a function, SQLite invokes that function to destroy the
  2970. ** value V after it has finished using the value V.
  2971. **
  2972. ** {H13548} In calls to [sqlite3_bind_zeroblob(S,N,V,L)] the value bound
  2973. ** is a BLOB of L bytes, or a zero-length BLOB if L is negative.
  2974. **
  2975. ** {H13551} In calls to [sqlite3_bind_value(S,N,V)] the V argument may
  2976. ** be either a [protected sqlite3_value] object or an
  2977. ** [unprotected sqlite3_value] object.
  2978. */
  2979. int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
  2980. int sqlite3_bind_double(sqlite3_stmt*, int, double);
  2981. int sqlite3_bind_int(sqlite3_stmt*, int, int);
  2982. int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
  2983. int sqlite3_bind_null(sqlite3_stmt*, int);
  2984. int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
  2985. int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
  2986. int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
  2987. int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
  2988. /*
  2989. ** CAPI3REF: Number Of SQL Parameters {H13600} <S70300>
  2990. **
  2991. ** This routine can be used to find the number of [SQL parameters]
  2992. ** in a [prepared statement]. SQL parameters are tokens of the
  2993. ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
  2994. ** placeholders for values that are [sqlite3_bind_blob | bound]
  2995. ** to the parameters at a later time.
  2996. **
  2997. ** This routine actually returns the index of the largest (rightmost)
  2998. ** parameter. For all forms except ?NNN, this will correspond to the
  2999. ** number of unique parameters. If parameters of the ?NNN are used,
  3000. ** there may be gaps in the list.
  3001. **
  3002. ** See also: [sqlite3_bind_blob|sqlite3_bind()],
  3003. ** [sqlite3_bind_parameter_name()], and
  3004. ** [sqlite3_bind_parameter_index()].
  3005. **
  3006. ** INVARIANTS:
  3007. **
  3008. ** {H13601} The [sqlite3_bind_parameter_count(S)] interface returns
  3009. ** the largest index of all SQL parameters in the
  3010. ** [prepared statement] S, or 0 if S contains no SQL parameters.
  3011. */
  3012. int sqlite3_bind_parameter_count(sqlite3_stmt*);
  3013. /*
  3014. ** CAPI3REF: Name Of A Host Parameter {H13620} <S70300>
  3015. **
  3016. ** This routine returns a pointer to the name of the n-th
  3017. ** [SQL parameter] in a [prepared statement].
  3018. ** SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
  3019. ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
  3020. ** respectively.
  3021. ** In other words, the initial ":" or "$" or "@" or "?"
  3022. ** is included as part of the name.
  3023. ** Parameters of the form "?" without a following integer have no name
  3024. ** and are also referred to as "anonymous parameters".
  3025. **
  3026. ** The first host parameter has an index of 1, not 0.
  3027. **
  3028. ** If the value n is out of range or if the n-th parameter is
  3029. ** nameless, then NULL is returned. The returned string is
  3030. ** always in UTF-8 encoding even if the named parameter was
  3031. ** originally specified as UTF-16 in [sqlite3_prepare16()] or
  3032. ** [sqlite3_prepare16_v2()].
  3033. **
  3034. ** See also: [sqlite3_bind_blob|sqlite3_bind()],
  3035. ** [sqlite3_bind_parameter_count()], and
  3036. ** [sqlite3_bind_parameter_index()].
  3037. **
  3038. ** INVARIANTS:
  3039. **
  3040. ** {H13621} The [sqlite3_bind_parameter_name(S,N)] interface returns
  3041. ** a UTF-8 rendering of the name of the SQL parameter in
  3042. ** the [prepared statement] S having index N, or
  3043. ** NULL if there is no SQL parameter with index N or if the
  3044. ** parameter with index N is an anonymous parameter "?".
  3045. */
  3046. const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
  3047. /*
  3048. ** CAPI3REF: Index Of A Parameter With A Given Name {H13640} <S70300>
  3049. **
  3050. ** Return the index of an SQL parameter given its name. The
  3051. ** index value returned is suitable for use as the second
  3052. ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. A zero
  3053. ** is returned if no matching parameter is found. The parameter
  3054. ** name must be given in UTF-8 even if the original statement
  3055. ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
  3056. **
  3057. ** See also: [sqlite3_bind_blob|sqlite3_bind()],
  3058. ** [sqlite3_bind_parameter_count()], and
  3059. ** [sqlite3_bind_parameter_index()].
  3060. **
  3061. ** INVARIANTS:
  3062. **
  3063. ** {H13641} The [sqlite3_bind_parameter_index(S,N)] interface returns
  3064. ** the index of SQL parameter in the [prepared statement]
  3065. ** S whose name matches the UTF-8 string N, or 0 if there is
  3066. ** no match.
  3067. */
  3068. int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
  3069. /*
  3070. ** CAPI3REF: Reset All Bindings On A Prepared Statement {H13660} <S70300>
  3071. **
  3072. ** Contrary to the intuition of many, [sqlite3_reset()] does not reset
  3073. ** the [sqlite3_bind_blob | bindings] on a [prepared statement].
  3074. ** Use this routine to reset all host parameters to NULL.
  3075. **
  3076. ** INVARIANTS:
  3077. **
  3078. ** {H13661} The [sqlite3_clear_bindings(S)] interface resets all SQL
  3079. ** parameter bindings in the [prepared statement] S back to NULL.
  3080. */
  3081. int sqlite3_clear_bindings(sqlite3_stmt*);
  3082. /*
  3083. ** CAPI3REF: Number Of Columns In A Result Set {H13710} <S10700>
  3084. **
  3085. ** Return the number of columns in the result set returned by the
  3086. ** [prepared statement]. This routine returns 0 if pStmt is an SQL
  3087. ** statement that does not return data (for example an [UPDATE]).
  3088. **
  3089. ** INVARIANTS:
  3090. **
  3091. ** {H13711} The [sqlite3_column_count(S)] interface returns the number of
  3092. ** columns in the result set generated by the [prepared statement] S,
  3093. ** or 0 if S does not generate a result set.
  3094. */
  3095. int sqlite3_column_count(sqlite3_stmt *pStmt);
  3096. /*
  3097. ** CAPI3REF: Column Names In A Result Set {H13720} <S10700>
  3098. **
  3099. ** These routines return the name assigned to a particular column
  3100. ** in the result set of a [SELECT] statement. The sqlite3_column_name()
  3101. ** interface returns a pointer to a zero-terminated UTF-8 string
  3102. ** and sqlite3_column_name16() returns a pointer to a zero-terminated
  3103. ** UTF-16 string. The first parameter is the [prepared statement]
  3104. ** that implements the [SELECT] statement. The second parameter is the
  3105. ** column number. The leftmost column is number 0.
  3106. **
  3107. ** The returned string pointer is valid until either the [prepared statement]
  3108. ** is destroyed by [sqlite3_finalize()] or until the next call to
  3109. ** sqlite3_column_name() or sqlite3_column_name16() on the same column.
  3110. **
  3111. ** If sqlite3_malloc() fails during the processing of either routine
  3112. ** (for example during a conversion from UTF-8 to UTF-16) then a
  3113. ** NULL pointer is returned.
  3114. **
  3115. ** The name of a result column is the value of the "AS" clause for
  3116. ** that column, if there is an AS clause. If there is no AS clause
  3117. ** then the name of the column is unspecified and may change from
  3118. ** one release of SQLite to the next.
  3119. **
  3120. ** INVARIANTS:
  3121. **
  3122. ** {H13721} A successful invocation of the [sqlite3_column_name(S,N)]
  3123. ** interface returns the name of the Nth column (where 0 is
  3124. ** the leftmost column) for the result set of the
  3125. ** [prepared statement] S as a zero-terminated UTF-8 string.
  3126. **
  3127. ** {H13723} A successful invocation of the [sqlite3_column_name16(S,N)]
  3128. ** interface returns the name of the Nth column (where 0 is
  3129. ** the leftmost column) for the result set of the
  3130. ** [prepared statement] S as a zero-terminated UTF-16 string
  3131. ** in the native byte order.
  3132. **
  3133. ** {H13724} The [sqlite3_column_name()] and [sqlite3_column_name16()]
  3134. ** interfaces return a NULL pointer if they are unable to
  3135. ** allocate memory to hold their normal return strings.
  3136. **
  3137. ** {H13725} If the N parameter to [sqlite3_column_name(S,N)] or
  3138. ** [sqlite3_column_name16(S,N)] is out of range, then the
  3139. ** interfaces return a NULL pointer.
  3140. **
  3141. ** {H13726} The strings returned by [sqlite3_column_name(S,N)] and
  3142. ** [sqlite3_column_name16(S,N)] are valid until the next
  3143. ** call to either routine with the same S and N parameters
  3144. ** or until [sqlite3_finalize(S)] is called.
  3145. **
  3146. ** {H13727} When a result column of a [SELECT] statement contains
  3147. ** an AS clause, the name of that column is the identifier
  3148. ** to the right of the AS keyword.
  3149. */
  3150. const char *sqlite3_column_name(sqlite3_stmt*, int N);
  3151. const void *sqlite3_column_name16(sqlite3_stmt*, int N);
  3152. /*
  3153. ** CAPI3REF: Source Of Data In A Query Result {H13740} <S10700>
  3154. **
  3155. ** These routines provide a means to determine what column of what
  3156. ** table in which database a result of a [SELECT] statement comes from.
  3157. ** The name of the database or table or column can be returned as
  3158. ** either a UTF-8 or UTF-16 string. The _database_ routines return
  3159. ** the database name, the _table_ routines return the table name, and
  3160. ** the origin_ routines return the column name.
  3161. ** The returned string is valid until the [prepared statement] is destroyed
  3162. ** using [sqlite3_finalize()] or until the same information is requested
  3163. ** again in a different encoding.
  3164. **
  3165. ** The names returned are the original un-aliased names of the
  3166. ** database, table, and column.
  3167. **
  3168. ** The first argument to the following calls is a [prepared statement].
  3169. ** These functions return information about the Nth column returned by
  3170. ** the statement, where N is the second function argument.
  3171. **
  3172. ** If the Nth column returned by the statement is an expression or
  3173. ** subquery and is not a column value, then all of these functions return
  3174. ** NULL. These routine might also return NULL if a memory allocation error
  3175. ** occurs. Otherwise, they return the name of the attached database, table
  3176. ** and column that query result column was extracted from.
  3177. **
  3178. ** As with all other SQLite APIs, those postfixed with "16" return
  3179. ** UTF-16 encoded strings, the other functions return UTF-8. {END}
  3180. **
  3181. ** These APIs are only available if the library was compiled with the
  3182. ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
  3183. **
  3184. ** {A13751}
  3185. ** If two or more threads call one or more of these routines against the same
  3186. ** prepared statement and column at the same time then the results are
  3187. ** undefined.
  3188. **
  3189. ** INVARIANTS:
  3190. **
  3191. ** {H13741} The [sqlite3_column_database_name(S,N)] interface returns either
  3192. ** the UTF-8 zero-terminated name of the database from which the
  3193. ** Nth result column of the [prepared statement] S is extracted,
  3194. ** or NULL if the Nth column of S is a general expression
  3195. ** or if unable to allocate memory to store the name.
  3196. **
  3197. ** {H13742} The [sqlite3_column_database_name16(S,N)] interface returns either
  3198. ** the UTF-16 native byte order zero-terminated name of the database
  3199. ** from which the Nth result column of the [prepared statement] S is
  3200. ** extracted, or NULL if the Nth column of S is a general expression
  3201. ** or if unable to allocate memory to store the name.
  3202. **
  3203. ** {H13743} The [sqlite3_column_table_name(S,N)] interface returns either
  3204. ** the UTF-8 zero-terminated name of the table from which the
  3205. ** Nth result column of the [prepared statement] S is extracted,
  3206. ** or NULL if the Nth column of S is a general expression
  3207. ** or if unable to allocate memory to store the name.
  3208. **
  3209. ** {H13744} The [sqlite3_column_table_name16(S,N)] interface returns either
  3210. ** the UTF-16 native byte order zero-terminated name of the table
  3211. ** from which the Nth result column of the [prepared statement] S is
  3212. ** extracted, or NULL if the Nth column of S is a general expression
  3213. ** or if unable to allocate memory to store the name.
  3214. **
  3215. ** {H13745} The [sqlite3_column_origin_name(S,N)] interface returns either
  3216. ** the UTF-8 zero-terminated name of the table column from which the
  3217. ** Nth result column of the [prepared statement] S is extracted,
  3218. ** or NULL if the Nth column of S is a general expression
  3219. ** or if unable to allocate memory to store the name.
  3220. **
  3221. ** {H13746} The [sqlite3_column_origin_name16(S,N)] interface returns either
  3222. ** the UTF-16 native byte order zero-terminated name of the table
  3223. ** column from which the Nth result column of the
  3224. ** [prepared statement] S is extracted, or NULL if the Nth column
  3225. ** of S is a general expression or if unable to allocate memory
  3226. ** to store the name.
  3227. **
  3228. ** {H13748} The return values from
  3229. ** [sqlite3_column_database_name | column metadata interfaces]
  3230. ** are valid for the lifetime of the [prepared statement]
  3231. ** or until the encoding is changed by another metadata
  3232. ** interface call for the same prepared statement and column.
  3233. **
  3234. ** ASSUMPTIONS:
  3235. **
  3236. ** {A13751} If two or more threads call one or more
  3237. ** [sqlite3_column_database_name | column metadata interfaces]
  3238. ** for the same [prepared statement] and result column
  3239. ** at the same time then the results are undefined.
  3240. */
  3241. const char *sqlite3_column_database_name(sqlite3_stmt*,int);
  3242. const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
  3243. const char *sqlite3_column_table_name(sqlite3_stmt*,int);
  3244. const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
  3245. const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
  3246. const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
  3247. /*
  3248. ** CAPI3REF: Declared Datatype Of A Query Result {H13760} <S10700>
  3249. **
  3250. ** The first parameter is a [prepared statement].
  3251. ** If this statement is a [SELECT] statement and the Nth column of the
  3252. ** returned result set of that [SELECT] is a table column (not an
  3253. ** expression or subquery) then the declared type of the table
  3254. ** column is returned. If the Nth column of the result set is an
  3255. ** expression or subquery, then a NULL pointer is returned.
  3256. ** The returned string is always UTF-8 encoded. {END}
  3257. **
  3258. ** For example, given the database schema:
  3259. **
  3260. ** CREATE TABLE t1(c1 VARIANT);
  3261. **
  3262. ** and the following statement to be compiled:
  3263. **
  3264. ** SELECT c1 + 1, c1 FROM t1;
  3265. **
  3266. ** this routine would return the string "VARIANT" for the second result
  3267. ** column (i==1), and a NULL pointer for the first result column (i==0).
  3268. **
  3269. ** SQLite uses dynamic run-time typing. So just because a column
  3270. ** is declared to contain a particular type does not mean that the
  3271. ** data stored in that column is of the declared type. SQLite is
  3272. ** strongly typed, but the typing is dynamic not static. Type
  3273. ** is associated with individual values, not with the containers
  3274. ** used to hold those values.
  3275. **
  3276. ** INVARIANTS:
  3277. **
  3278. ** {H13761} A successful call to [sqlite3_column_decltype(S,N)] returns a
  3279. ** zero-terminated UTF-8 string containing the declared datatype
  3280. ** of the table column that appears as the Nth column (numbered
  3281. ** from 0) of the result set to the [prepared statement] S.
  3282. **
  3283. ** {H13762} A successful call to [sqlite3_column_decltype16(S,N)]
  3284. ** returns a zero-terminated UTF-16 native byte order string
  3285. ** containing the declared datatype of the table column that appears
  3286. ** as the Nth column (numbered from 0) of the result set to the
  3287. ** [prepared statement] S.
  3288. **
  3289. ** {H13763} If N is less than 0 or N is greater than or equal to
  3290. ** the number of columns in the [prepared statement] S,
  3291. ** or if the Nth column of S is an expression or subquery rather
  3292. ** than a table column, or if a memory allocation failure
  3293. ** occurs during encoding conversions, then
  3294. ** calls to [sqlite3_column_decltype(S,N)] or
  3295. ** [sqlite3_column_decltype16(S,N)] return NULL.
  3296. */
  3297. const char *sqlite3_column_decltype(sqlite3_stmt*,int);
  3298. const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
  3299. /*
  3300. ** CAPI3REF: Evaluate An SQL Statement {H13200} <S10000>
  3301. **
  3302. ** After a [prepared statement] has been prepared using either
  3303. ** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
  3304. ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
  3305. ** must be called one or more times to evaluate the statement.
  3306. **
  3307. ** The details of the behavior of the sqlite3_step() interface depend
  3308. ** on whether the statement was prepared using the newer "v2" interface
  3309. ** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
  3310. ** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
  3311. ** new "v2" interface is recommended for new applications but the legacy
  3312. ** interface will continue to be supported.
  3313. **
  3314. ** In the legacy interface, the return value will be either [SQLITE_BUSY],
  3315. ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
  3316. ** With the "v2" interface, any of the other [result codes] or
  3317. ** [extended result codes] might be returned as well.
  3318. **
  3319. ** [SQLITE_BUSY] means that the database engine was unable to acquire the
  3320. ** database locks it needs to do its job. If the statement is a [COMMIT]
  3321. ** or occurs outside of an explicit transaction, then you can retry the
  3322. ** statement. If the statement is not a [COMMIT] and occurs within a
  3323. ** explicit transaction then you should rollback the transaction before
  3324. ** continuing.
  3325. **
  3326. ** [SQLITE_DONE] means that the statement has finished executing
  3327. ** successfully. sqlite3_step() should not be called again on this virtual
  3328. ** machine without first calling [sqlite3_reset()] to reset the virtual
  3329. ** machine back to its initial state.
  3330. **
  3331. ** If the SQL statement being executed returns any data, then [SQLITE_ROW]
  3332. ** is returned each time a new row of data is ready for processing by the
  3333. ** caller. The values may be accessed using the [column access functions].
  3334. ** sqlite3_step() is called again to retrieve the next row of data.
  3335. **
  3336. ** [SQLITE_ERROR] means that a run-time error (such as a constraint
  3337. ** violation) has occurred. sqlite3_step() should not be called again on
  3338. ** the VM. More information may be found by calling [sqlite3_errmsg()].
  3339. ** With the legacy interface, a more specific error code (for example,
  3340. ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
  3341. ** can be obtained by calling [sqlite3_reset()] on the
  3342. ** [prepared statement]. In the "v2" interface,
  3343. ** the more specific error code is returned directly by sqlite3_step().
  3344. **
  3345. ** [SQLITE_MISUSE] means that the this routine was called inappropriately.
  3346. ** Perhaps it was called on a [prepared statement] that has
  3347. ** already been [sqlite3_finalize | finalized] or on one that had
  3348. ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
  3349. ** be the case that the same database connection is being used by two or
  3350. ** more threads at the same moment in time.
  3351. **
  3352. ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
  3353. ** API always returns a generic error code, [SQLITE_ERROR], following any
  3354. ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
  3355. ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
  3356. ** specific [error codes] that better describes the error.
  3357. ** We admit that this is a goofy design. The problem has been fixed
  3358. ** with the "v2" interface. If you prepare all of your SQL statements
  3359. ** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
  3360. ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
  3361. ** then the more specific [error codes] are returned directly
  3362. ** by sqlite3_step(). The use of the "v2" interface is recommended.
  3363. **
  3364. ** INVARIANTS:
  3365. **
  3366. ** {H13202} If the [prepared statement] S is ready to be run, then
  3367. ** [sqlite3_step(S)] advances that prepared statement until
  3368. ** completion or until it is ready to return another row of the
  3369. ** result set, or until an [sqlite3_interrupt | interrupt]
  3370. ** or a run-time error occurs.
  3371. **
  3372. ** {H15304} When a call to [sqlite3_step(S)] causes the [prepared statement]
  3373. ** S to run to completion, the function returns [SQLITE_DONE].
  3374. **
  3375. ** {H15306} When a call to [sqlite3_step(S)] stops because it is ready to
  3376. ** return another row of the result set, it returns [SQLITE_ROW].
  3377. **
  3378. ** {H15308} If a call to [sqlite3_step(S)] encounters an
  3379. ** [sqlite3_interrupt | interrupt] or a run-time error,
  3380. ** it returns an appropriate error code that is not one of
  3381. ** [SQLITE_OK], [SQLITE_ROW], or [SQLITE_DONE].
  3382. **
  3383. ** {H15310} If an [sqlite3_interrupt | interrupt] or a run-time error
  3384. ** occurs during a call to [sqlite3_step(S)]
  3385. ** for a [prepared statement] S created using
  3386. ** legacy interfaces [sqlite3_prepare()] or
  3387. ** [sqlite3_prepare16()], then the function returns either
  3388. ** [SQLITE_ERROR], [SQLITE_BUSY], or [SQLITE_MISUSE].
  3389. */
  3390. int sqlite3_step(sqlite3_stmt*);
  3391. /*
  3392. ** CAPI3REF: Number of columns in a result set {H13770} <S10700>
  3393. **
  3394. ** Returns the number of values in the current row of the result set.
  3395. **
  3396. ** INVARIANTS:
  3397. **
  3398. ** {H13771} After a call to [sqlite3_step(S)] that returns [SQLITE_ROW],
  3399. ** the [sqlite3_data_count(S)] routine will return the same value
  3400. ** as the [sqlite3_column_count(S)] function.
  3401. **
  3402. ** {H13772} After [sqlite3_step(S)] has returned any value other than
  3403. ** [SQLITE_ROW] or before [sqlite3_step(S)] has been called on the
  3404. ** [prepared statement] for the first time since it was
  3405. ** [sqlite3_prepare | prepared] or [sqlite3_reset | reset],
  3406. ** the [sqlite3_data_count(S)] routine returns zero.
  3407. */
  3408. int sqlite3_data_count(sqlite3_stmt *pStmt);
  3409. /*
  3410. ** CAPI3REF: Fundamental Datatypes {H10265} <S10110><S10120>
  3411. ** KEYWORDS: SQLITE_TEXT
  3412. **
  3413. ** {H10266} Every value in SQLite has one of five fundamental datatypes:
  3414. **
  3415. ** <ul>
  3416. ** <li> 64-bit signed integer
  3417. ** <li> 64-bit IEEE floating point number
  3418. ** <li> string
  3419. ** <li> BLOB
  3420. ** <li> NULL
  3421. ** </ul> {END}
  3422. **
  3423. ** These constants are codes for each of those types.
  3424. **
  3425. ** Note that the SQLITE_TEXT constant was also used in SQLite version 2
  3426. ** for a completely different meaning. Software that links against both
  3427. ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
  3428. ** SQLITE_TEXT.
  3429. */
  3430. #define SQLITE_INTEGER 1
  3431. #define SQLITE_FLOAT 2
  3432. #define SQLITE_BLOB 4
  3433. #define SQLITE_NULL 5
  3434. #ifdef SQLITE_TEXT
  3435. # undef SQLITE_TEXT
  3436. #else
  3437. # define SQLITE_TEXT 3
  3438. #endif
  3439. #define SQLITE3_TEXT 3
  3440. /*
  3441. ** CAPI3REF: Result Values From A Query {H13800} <S10700>
  3442. ** KEYWORDS: {column access functions}
  3443. **
  3444. ** These routines form the "result set query" interface.
  3445. **
  3446. ** These routines return information about a single column of the current
  3447. ** result row of a query. In every case the first argument is a pointer
  3448. ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
  3449. ** that was returned from [sqlite3_prepare_v2()] or one of its variants)
  3450. ** and the second argument is the index of the column for which information
  3451. ** should be returned. The leftmost column of the result set has the index 0.
  3452. **
  3453. ** If the SQL statement does not currently point to a valid row, or if the
  3454. ** column index is out of range, the result is undefined.
  3455. ** These routines may only be called when the most recent call to
  3456. ** [sqlite3_step()] has returned [SQLITE_ROW] and neither
  3457. ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
  3458. ** If any of these routines are called after [sqlite3_reset()] or
  3459. ** [sqlite3_finalize()] or after [sqlite3_step()] has returned
  3460. ** something other than [SQLITE_ROW], the results are undefined.
  3461. ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
  3462. ** are called from a different thread while any of these routines
  3463. ** are pending, then the results are undefined.
  3464. **
  3465. ** The sqlite3_column_type() routine returns the
  3466. ** [SQLITE_INTEGER | datatype code] for the initial data type
  3467. ** of the result column. The returned value is one of [SQLITE_INTEGER],
  3468. ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value
  3469. ** returned by sqlite3_column_type() is only meaningful if no type
  3470. ** conversions have occurred as described below. After a type conversion,
  3471. ** the value returned by sqlite3_column_type() is undefined. Future
  3472. ** versions of SQLite may change the behavior of sqlite3_column_type()
  3473. ** following a type conversion.
  3474. **
  3475. ** If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
  3476. ** routine returns the number of bytes in that BLOB or string.
  3477. ** If the result is a UTF-16 string, then sqlite3_column_bytes() converts
  3478. ** the string to UTF-8 and then returns the number of bytes.
  3479. ** If the result is a numeric value then sqlite3_column_bytes() uses
  3480. ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
  3481. ** the number of bytes in that string.
  3482. ** The value returned does not include the zero terminator at the end
  3483. ** of the string. For clarity: the value returned is the number of
  3484. ** bytes in the string, not the number of characters.
  3485. **
  3486. ** Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
  3487. ** even empty strings, are always zero terminated. The return
  3488. ** value from sqlite3_column_blob() for a zero-length BLOB is an arbitrary
  3489. ** pointer, possibly even a NULL pointer.
  3490. **
  3491. ** The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes()
  3492. ** but leaves the result in UTF-16 in native byte order instead of UTF-8.
  3493. ** The zero terminator is not included in this count.
  3494. **
  3495. ** The object returned by [sqlite3_column_value()] is an
  3496. ** [unprotected sqlite3_value] object. An unprotected sqlite3_value object
  3497. ** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
  3498. ** If the [unprotected sqlite3_value] object returned by
  3499. ** [sqlite3_column_value()] is used in any other way, including calls
  3500. ** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
  3501. ** or [sqlite3_value_bytes()], then the behavior is undefined.
  3502. **
  3503. ** These routines attempt to convert the value where appropriate. For
  3504. ** example, if the internal representation is FLOAT and a text result
  3505. ** is requested, [sqlite3_snprintf()] is used internally to perform the
  3506. ** conversion automatically. The following table details the conversions
  3507. ** that are applied:
  3508. **
  3509. ** <blockquote>
  3510. ** <table border="1">
  3511. ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
  3512. **
  3513. ** <tr><td> NULL <td> INTEGER <td> Result is 0
  3514. ** <tr><td> NULL <td> FLOAT <td> Result is 0.0
  3515. ** <tr><td> NULL <td> TEXT <td> Result is NULL pointer
  3516. ** <tr><td> NULL <td> BLOB <td> Result is NULL pointer
  3517. ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
  3518. ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
  3519. ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
  3520. ** <tr><td> FLOAT <td> INTEGER <td> Convert from float to integer
  3521. ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
  3522. ** <tr><td> FLOAT <td> BLOB <td> Same as FLOAT->TEXT
  3523. ** <tr><td> TEXT <td> INTEGER <td> Use atoi()
  3524. ** <tr><td> TEXT <td> FLOAT <td> Use atof()
  3525. ** <tr><td> TEXT <td> BLOB <td> No change
  3526. ** <tr><td> BLOB <td> INTEGER <td> Convert to TEXT then use atoi()
  3527. ** <tr><td> BLOB <td> FLOAT <td> Convert to TEXT then use atof()
  3528. ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
  3529. ** </table>
  3530. ** </blockquote>
  3531. **
  3532. ** The table above makes reference to standard C library functions atoi()
  3533. ** and atof(). SQLite does not really use these functions. It has its
  3534. ** own equivalent internal routines. The atoi() and atof() names are
  3535. ** used in the table for brevity and because they are familiar to most
  3536. ** C programmers.
  3537. **
  3538. ** Note that when type conversions occur, pointers returned by prior
  3539. ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
  3540. ** sqlite3_column_text16() may be invalidated.
  3541. ** Type conversions and pointer invalidations might occur
  3542. ** in the following cases:
  3543. **
  3544. ** <ul>
  3545. ** <li> The initial content is a BLOB and sqlite3_column_text() or
  3546. ** sqlite3_column_text16() is called. A zero-terminator might
  3547. ** need to be added to the string.</li>
  3548. ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
  3549. ** sqlite3_column_text16() is called. The content must be converted
  3550. ** to UTF-16.</li>
  3551. ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
  3552. ** sqlite3_column_text() is called. The content must be converted
  3553. ** to UTF-8.</li>
  3554. ** </ul>
  3555. **
  3556. ** Conversions between UTF-16be and UTF-16le are always done in place and do
  3557. ** not invalidate a prior pointer, though of course the content of the buffer
  3558. ** that the prior pointer points to will have been modified. Other kinds
  3559. ** of conversion are done in place when it is possible, but sometimes they
  3560. ** are not possible and in those cases prior pointers are invalidated.
  3561. **
  3562. ** The safest and easiest to remember policy is to invoke these routines
  3563. ** in one of the following ways:
  3564. **
  3565. ** <ul>
  3566. ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
  3567. ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
  3568. ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
  3569. ** </ul>
  3570. **
  3571. ** In other words, you should call sqlite3_column_text(),
  3572. ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
  3573. ** into the desired format, then invoke sqlite3_column_bytes() or
  3574. ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
  3575. ** to sqlite3_column_text() or sqlite3_column_blob() with calls to
  3576. ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
  3577. ** with calls to sqlite3_column_bytes().
  3578. **
  3579. ** The pointers returned are valid until a type conversion occurs as
  3580. ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
  3581. ** [sqlite3_finalize()] is called. The memory space used to hold strings
  3582. ** and BLOBs is freed automatically. Do <b>not</b> pass the pointers returned
  3583. ** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
  3584. ** [sqlite3_free()].
  3585. **
  3586. ** If a memory allocation error occurs during the evaluation of any
  3587. ** of these routines, a default value is returned. The default value
  3588. ** is either the integer 0, the floating point number 0.0, or a NULL
  3589. ** pointer. Subsequent calls to [sqlite3_errcode()] will return
  3590. ** [SQLITE_NOMEM].
  3591. **
  3592. ** INVARIANTS:
  3593. **
  3594. ** {H13803} The [sqlite3_column_blob(S,N)] interface converts the
  3595. ** Nth column in the current row of the result set for
  3596. ** the [prepared statement] S into a BLOB and then returns a
  3597. ** pointer to the converted value.
  3598. **
  3599. ** {H13806} The [sqlite3_column_bytes(S,N)] interface returns the
  3600. ** number of bytes in the BLOB or string (exclusive of the
  3601. ** zero terminator on the string) that was returned by the
  3602. ** most recent call to [sqlite3_column_blob(S,N)] or
  3603. ** [sqlite3_column_text(S,N)].
  3604. **
  3605. ** {H13809} The [sqlite3_column_bytes16(S,N)] interface returns the
  3606. ** number of bytes in the string (exclusive of the
  3607. ** zero terminator on the string) that was returned by the
  3608. ** most recent call to [sqlite3_column_text16(S,N)].
  3609. **
  3610. ** {H13812} The [sqlite3_column_double(S,N)] interface converts the
  3611. ** Nth column in the current row of the result set for the
  3612. ** [prepared statement] S into a floating point value and
  3613. ** returns a copy of that value.
  3614. **
  3615. ** {H13815} The [sqlite3_column_int(S,N)] interface converts the
  3616. ** Nth column in the current row of the result set for the
  3617. ** [prepared statement] S into a 64-bit signed integer and
  3618. ** returns the lower 32 bits of that integer.
  3619. **
  3620. ** {H13818} The [sqlite3_column_int64(S,N)] interface converts the
  3621. ** Nth column in the current row of the result set for the
  3622. ** [prepared statement] S into a 64-bit signed integer and
  3623. ** returns a copy of that integer.
  3624. **
  3625. ** {H13821} The [sqlite3_column_text(S,N)] interface converts the
  3626. ** Nth column in the current row of the result set for
  3627. ** the [prepared statement] S into a zero-terminated UTF-8
  3628. ** string and returns a pointer to that string.
  3629. **
  3630. ** {H13824} The [sqlite3_column_text16(S,N)] interface converts the
  3631. ** Nth column in the current row of the result set for the
  3632. ** [prepared statement] S into a zero-terminated 2-byte
  3633. ** aligned UTF-16 native byte order string and returns
  3634. ** a pointer to that string.
  3635. **
  3636. ** {H13827} The [sqlite3_column_type(S,N)] interface returns
  3637. ** one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT],
  3638. ** [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for
  3639. ** the Nth column in the current row of the result set for
  3640. ** the [prepared statement] S.
  3641. **
  3642. ** {H13830} The [sqlite3_column_value(S,N)] interface returns a
  3643. ** pointer to an [unprotected sqlite3_value] object for the
  3644. ** Nth column in the current row of the result set for
  3645. ** the [prepared statement] S.
  3646. */
  3647. const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
  3648. int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
  3649. int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
  3650. double sqlite3_column_double(sqlite3_stmt*, int iCol);
  3651. int sqlite3_column_int(sqlite3_stmt*, int iCol);
  3652. sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
  3653. const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
  3654. const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
  3655. int sqlite3_column_type(sqlite3_stmt*, int iCol);
  3656. sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
  3657. /*
  3658. ** CAPI3REF: Destroy A Prepared Statement Object {H13300} <S70300><S30100>
  3659. **
  3660. ** The sqlite3_finalize() function is called to delete a [prepared statement].
  3661. ** If the statement was executed successfully or not executed at all, then
  3662. ** SQLITE_OK is returned. If execution of the statement failed then an
  3663. ** [error code] or [extended error code] is returned.
  3664. **
  3665. ** This routine can be called at any point during the execution of the
  3666. ** [prepared statement]. If the virtual machine has not
  3667. ** completed execution when this routine is called, that is like
  3668. ** encountering an error or an [sqlite3_interrupt | interrupt].
  3669. ** Incomplete updates may be rolled back and transactions canceled,
  3670. ** depending on the circumstances, and the
  3671. ** [error code] returned will be [SQLITE_ABORT].
  3672. **
  3673. ** INVARIANTS:
  3674. **
  3675. ** {H11302} The [sqlite3_finalize(S)] interface destroys the
  3676. ** [prepared statement] S and releases all
  3677. ** memory and file resources held by that object.
  3678. **
  3679. ** {H11304} If the most recent call to [sqlite3_step(S)] for the
  3680. ** [prepared statement] S returned an error,
  3681. ** then [sqlite3_finalize(S)] returns that same error.
  3682. */
  3683. int sqlite3_finalize(sqlite3_stmt *pStmt);
  3684. /*
  3685. ** CAPI3REF: Reset A Prepared Statement Object {H13330} <S70300>
  3686. **
  3687. ** The sqlite3_reset() function is called to reset a [prepared statement]
  3688. ** object back to its initial state, ready to be re-executed.
  3689. ** Any SQL statement variables that had values bound to them using
  3690. ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
  3691. ** Use [sqlite3_clear_bindings()] to reset the bindings.
  3692. **
  3693. ** {H11332} The [sqlite3_reset(S)] interface resets the [prepared statement] S
  3694. ** back to the beginning of its program.
  3695. **
  3696. ** {H11334} If the most recent call to [sqlite3_step(S)] for the
  3697. ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
  3698. ** or if [sqlite3_step(S)] has never before been called on S,
  3699. ** then [sqlite3_reset(S)] returns [SQLITE_OK].
  3700. **
  3701. ** {H11336} If the most recent call to [sqlite3_step(S)] for the
  3702. ** [prepared statement] S indicated an error, then
  3703. ** [sqlite3_reset(S)] returns an appropriate [error code].
  3704. **
  3705. ** {H11338} The [sqlite3_reset(S)] interface does not change the values
  3706. ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
  3707. */
  3708. int sqlite3_reset(sqlite3_stmt *pStmt);
  3709. /*
  3710. ** CAPI3REF: Create Or Redefine SQL Functions {H16100} <S20200>
  3711. ** KEYWORDS: {function creation routines}
  3712. ** KEYWORDS: {application-defined SQL function}
  3713. ** KEYWORDS: {application-defined SQL functions}
  3714. **
  3715. ** These two functions (collectively known as "function creation routines")
  3716. ** are used to add SQL functions or aggregates or to redefine the behavior
  3717. ** of existing SQL functions or aggregates. The only difference between the
  3718. ** two is that the second parameter, the name of the (scalar) function or
  3719. ** aggregate, is encoded in UTF-8 for sqlite3_create_function() and UTF-16
  3720. ** for sqlite3_create_function16().
  3721. **
  3722. ** The first parameter is the [database connection] to which the SQL
  3723. ** function is to be added. If a single program uses more than one database
  3724. ** connection internally, then SQL functions must be added individually to
  3725. ** each database connection.
  3726. **
  3727. ** The second parameter is the name of the SQL function to be created or
  3728. ** redefined. The length of the name is limited to 255 bytes, exclusive of
  3729. ** the zero-terminator. Note that the name length limit is in bytes, not
  3730. ** characters. Any attempt to create a function with a longer name
  3731. ** will result in [SQLITE_ERROR] being returned.
  3732. **
  3733. ** The third parameter is the number of arguments that the SQL function or
  3734. ** aggregate takes. If this parameter is negative, then the SQL function or
  3735. ** aggregate may take any number of arguments.
  3736. **
  3737. ** The fourth parameter, eTextRep, specifies what
  3738. ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
  3739. ** its parameters. Any SQL function implementation should be able to work
  3740. ** work with UTF-8, UTF-16le, or UTF-16be. But some implementations may be
  3741. ** more efficient with one encoding than another. It is allowed to
  3742. ** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
  3743. ** times with the same function but with different values of eTextRep.
  3744. ** When multiple implementations of the same function are available, SQLite
  3745. ** will pick the one that involves the least amount of data conversion.
  3746. ** If there is only a single implementation which does not care what text
  3747. ** encoding is used, then the fourth argument should be [SQLITE_ANY].
  3748. **
  3749. ** The fifth parameter is an arbitrary pointer. The implementation of the
  3750. ** function can gain access to this pointer using [sqlite3_user_data()].
  3751. **
  3752. ** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
  3753. ** pointers to C-language functions that implement the SQL function or
  3754. ** aggregate. A scalar SQL function requires an implementation of the xFunc
  3755. ** callback only, NULL pointers should be passed as the xStep and xFinal
  3756. ** parameters. An aggregate SQL function requires an implementation of xStep
  3757. ** and xFinal and NULL should be passed for xFunc. To delete an existing
  3758. ** SQL function or aggregate, pass NULL for all three function callbacks.
  3759. **
  3760. ** It is permitted to register multiple implementations of the same
  3761. ** functions with the same name but with either differing numbers of
  3762. ** arguments or differing preferred text encodings. SQLite will use
  3763. ** the implementation most closely matches the way in which the
  3764. ** SQL function is used.
  3765. **
  3766. ** INVARIANTS:
  3767. **
  3768. ** {H16103} The [sqlite3_create_function16()] interface behaves exactly
  3769. ** like [sqlite3_create_function()] in every way except that it
  3770. ** interprets the zFunctionName argument as zero-terminated UTF-16
  3771. ** native byte order instead of as zero-terminated UTF-8.
  3772. **
  3773. ** {H16106} A successful invocation of
  3774. ** the [sqlite3_create_function(D,X,N,E,...)] interface registers
  3775. ** or replaces callback functions in the [database connection] D
  3776. ** used to implement the SQL function named X with N parameters
  3777. ** and having a preferred text encoding of E.
  3778. **
  3779. ** {H16109} A successful call to [sqlite3_create_function(D,X,N,E,P,F,S,L)]
  3780. ** replaces the P, F, S, and L values from any prior calls with
  3781. ** the same D, X, N, and E values.
  3782. **
  3783. ** {H16112} The [sqlite3_create_function(D,X,...)] interface fails with
  3784. ** a return code of [SQLITE_ERROR] if the SQL function name X is
  3785. ** longer than 255 bytes exclusive of the zero terminator.
  3786. **
  3787. ** {H16118} Either F must be NULL and S and L are non-NULL or else F
  3788. ** is non-NULL and S and L are NULL, otherwise
  3789. ** [sqlite3_create_function(D,X,N,E,P,F,S,L)] returns [SQLITE_ERROR].
  3790. **
  3791. ** {H16121} The [sqlite3_create_function(D,...)] interface fails with an
  3792. ** error code of [SQLITE_BUSY] if there exist [prepared statements]
  3793. ** associated with the [database connection] D.
  3794. **
  3795. ** {H16124} The [sqlite3_create_function(D,X,N,...)] interface fails with an
  3796. ** error code of [SQLITE_ERROR] if parameter N (specifying the number
  3797. ** of arguments to the SQL function being registered) is less
  3798. ** than -1 or greater than 127.
  3799. **
  3800. ** {H16127} When N is non-negative, the [sqlite3_create_function(D,X,N,...)]
  3801. ** interface causes callbacks to be invoked for the SQL function
  3802. ** named X when the number of arguments to the SQL function is
  3803. ** exactly N.
  3804. **
  3805. ** {H16130} When N is -1, the [sqlite3_create_function(D,X,N,...)]
  3806. ** interface causes callbacks to be invoked for the SQL function
  3807. ** named X with any number of arguments.
  3808. **
  3809. ** {H16133} When calls to [sqlite3_create_function(D,X,N,...)]
  3810. ** specify multiple implementations of the same function X
  3811. ** and when one implementation has N>=0 and the other has N=(-1)
  3812. ** the implementation with a non-zero N is preferred.
  3813. **
  3814. ** {H16136} When calls to [sqlite3_create_function(D,X,N,E,...)]
  3815. ** specify multiple implementations of the same function X with
  3816. ** the same number of arguments N but with different
  3817. ** encodings E, then the implementation where E matches the
  3818. ** database encoding is preferred.
  3819. **
  3820. ** {H16139} For an aggregate SQL function created using
  3821. ** [sqlite3_create_function(D,X,N,E,P,0,S,L)] the finalizer
  3822. ** function L will always be invoked exactly once if the
  3823. ** step function S is called one or more times.
  3824. **
  3825. ** {H16142} When SQLite invokes either the xFunc or xStep function of
  3826. ** an application-defined SQL function or aggregate created
  3827. ** by [sqlite3_create_function()] or [sqlite3_create_function16()],
  3828. ** then the array of [sqlite3_value] objects passed as the
  3829. ** third parameter are always [protected sqlite3_value] objects.
  3830. */
  3831. int sqlite3_create_function(
  3832. sqlite3 *db,
  3833. const char *zFunctionName,
  3834. int nArg,
  3835. int eTextRep,
  3836. void *pApp,
  3837. void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
  3838. void (*xStep)(sqlite3_context*,int,sqlite3_value**),
  3839. void (*xFinal)(sqlite3_context*)
  3840. );
  3841. int sqlite3_create_function16(
  3842. sqlite3 *db,
  3843. const void *zFunctionName,
  3844. int nArg,
  3845. int eTextRep,
  3846. void *pApp,
  3847. void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
  3848. void (*xStep)(sqlite3_context*,int,sqlite3_value**),
  3849. void (*xFinal)(sqlite3_context*)
  3850. );
  3851. /*
  3852. ** CAPI3REF: Text Encodings {H10267} <S50200> <H16100>
  3853. **
  3854. ** These constant define integer codes that represent the various
  3855. ** text encodings supported by SQLite.
  3856. */
  3857. #define SQLITE_UTF8 1
  3858. #define SQLITE_UTF16LE 2
  3859. #define SQLITE_UTF16BE 3
  3860. #define SQLITE_UTF16 4 /* Use native byte order */
  3861. #define SQLITE_ANY 5 /* sqlite3_create_function only */
  3862. #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
  3863. /*
  3864. ** CAPI3REF: Deprecated Functions
  3865. ** DEPRECATED
  3866. **
  3867. ** These functions are [deprecated]. In order to maintain
  3868. ** backwards compatibility with older code, these functions continue
  3869. ** to be supported. However, new applications should avoid
  3870. ** the use of these functions. To help encourage people to avoid
  3871. ** using these functions, we are not going to tell you want they do.
  3872. */
  3873. int sqlite3_aggregate_count(sqlite3_context*);
  3874. int sqlite3_expired(sqlite3_stmt*);
  3875. int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
  3876. int sqlite3_global_recover(void);
  3877. void sqlite3_thread_cleanup(void);
  3878. int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
  3879. /*
  3880. ** CAPI3REF: Obtaining SQL Function Parameter Values {H15100} <S20200>
  3881. **
  3882. ** The C-language implementation of SQL functions and aggregates uses
  3883. ** this set of interface routines to access the parameter values on
  3884. ** the function or aggregate.
  3885. **
  3886. ** The xFunc (for scalar functions) or xStep (for aggregates) parameters
  3887. ** to [sqlite3_create_function()] and [sqlite3_create_function16()]
  3888. ** define callbacks that implement the SQL functions and aggregates.
  3889. ** The 4th parameter to these callbacks is an array of pointers to
  3890. ** [protected sqlite3_value] objects. There is one [sqlite3_value] object for
  3891. ** each parameter to the SQL function. These routines are used to
  3892. ** extract values from the [sqlite3_value] objects.
  3893. **
  3894. ** These routines work only with [protected sqlite3_value] objects.
  3895. ** Any attempt to use these routines on an [unprotected sqlite3_value]
  3896. ** object results in undefined behavior.
  3897. **
  3898. ** These routines work just like the corresponding [column access functions]
  3899. ** except that these routines take a single [protected sqlite3_value] object
  3900. ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
  3901. **
  3902. ** The sqlite3_value_text16() interface extracts a UTF-16 string
  3903. ** in the native byte-order of the host machine. The
  3904. ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
  3905. ** extract UTF-16 strings as big-endian and little-endian respectively.
  3906. **
  3907. ** The sqlite3_value_numeric_type() interface attempts to apply
  3908. ** numeric affinity to the value. This means that an attempt is
  3909. ** made to convert the value to an integer or floating point. If
  3910. ** such a conversion is possible without loss of information (in other
  3911. ** words, if the value is a string that looks like a number)
  3912. ** then the conversion is performed. Otherwise no conversion occurs.
  3913. ** The [SQLITE_INTEGER | datatype] after conversion is returned.
  3914. **
  3915. ** Please pay particular attention to the fact that the pointer returned
  3916. ** from [sqlite3_value_blob()], [sqlite3_value_text()], or
  3917. ** [sqlite3_value_text16()] can be invalidated by a subsequent call to
  3918. ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
  3919. ** or [sqlite3_value_text16()].
  3920. **
  3921. ** These routines must be called from the same thread as
  3922. ** the SQL function that supplied the [sqlite3_value*] parameters.
  3923. **
  3924. ** INVARIANTS:
  3925. **
  3926. ** {H15103} The [sqlite3_value_blob(V)] interface converts the
  3927. ** [protected sqlite3_value] object V into a BLOB and then
  3928. ** returns a pointer to the converted value.
  3929. **
  3930. ** {H15106} The [sqlite3_value_bytes(V)] interface returns the
  3931. ** number of bytes in the BLOB or string (exclusive of the
  3932. ** zero terminator on the string) that was returned by the
  3933. ** most recent call to [sqlite3_value_blob(V)] or
  3934. ** [sqlite3_value_text(V)].
  3935. **
  3936. ** {H15109} The [sqlite3_value_bytes16(V)] interface returns the
  3937. ** number of bytes in the string (exclusive of the
  3938. ** zero terminator on the string) that was returned by the
  3939. ** most recent call to [sqlite3_value_text16(V)],
  3940. ** [sqlite3_value_text16be(V)], or [sqlite3_value_text16le(V)].
  3941. **
  3942. ** {H15112} The [sqlite3_value_double(V)] interface converts the
  3943. ** [protected sqlite3_value] object V into a floating point value and
  3944. ** returns a copy of that value.
  3945. **
  3946. ** {H15115} The [sqlite3_value_int(V)] interface converts the
  3947. ** [protected sqlite3_value] object V into a 64-bit signed integer and
  3948. ** returns the lower 32 bits of that integer.
  3949. **
  3950. ** {H15118} The [sqlite3_value_int64(V)] interface converts the
  3951. ** [protected sqlite3_value] object V into a 64-bit signed integer and
  3952. ** returns a copy of that integer.
  3953. **
  3954. ** {H15121} The [sqlite3_value_text(V)] interface converts the
  3955. ** [protected sqlite3_value] object V into a zero-terminated UTF-8
  3956. ** string and returns a pointer to that string.
  3957. **
  3958. ** {H15124} The [sqlite3_value_text16(V)] interface converts the
  3959. ** [protected sqlite3_value] object V into a zero-terminated 2-byte
  3960. ** aligned UTF-16 native byte order
  3961. ** string and returns a pointer to that string.
  3962. **
  3963. ** {H15127} The [sqlite3_value_text16be(V)] interface converts the
  3964. ** [protected sqlite3_value] object V into a zero-terminated 2-byte
  3965. ** aligned UTF-16 big-endian
  3966. ** string and returns a pointer to that string.
  3967. **
  3968. ** {H15130} The [sqlite3_value_text16le(V)] interface converts the
  3969. ** [protected sqlite3_value] object V into a zero-terminated 2-byte
  3970. ** aligned UTF-16 little-endian
  3971. ** string and returns a pointer to that string.
  3972. **
  3973. ** {H15133} The [sqlite3_value_type(V)] interface returns
  3974. ** one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT],
  3975. ** [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for
  3976. ** the [sqlite3_value] object V.
  3977. **
  3978. ** {H15136} The [sqlite3_value_numeric_type(V)] interface converts
  3979. ** the [protected sqlite3_value] object V into either an integer or
  3980. ** a floating point value if it can do so without loss of
  3981. ** information, and returns one of [SQLITE_NULL],
  3982. ** [SQLITE_INTEGER], [SQLITE_FLOAT], [SQLITE_TEXT], or
  3983. ** [SQLITE_BLOB] as appropriate for the
  3984. ** [protected sqlite3_value] object V after the conversion attempt.
  3985. */
  3986. const void *sqlite3_value_blob(sqlite3_value*);
  3987. int sqlite3_value_bytes(sqlite3_value*);
  3988. int sqlite3_value_bytes16(sqlite3_value*);
  3989. double sqlite3_value_double(sqlite3_value*);
  3990. int sqlite3_value_int(sqlite3_value*);
  3991. sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
  3992. const unsigned char *sqlite3_value_text(sqlite3_value*);
  3993. const void *sqlite3_value_text16(sqlite3_value*);
  3994. const void *sqlite3_value_text16le(sqlite3_value*);
  3995. const void *sqlite3_value_text16be(sqlite3_value*);
  3996. int sqlite3_value_type(sqlite3_value*);
  3997. int sqlite3_value_numeric_type(sqlite3_value*);
  3998. /*
  3999. ** CAPI3REF: Obtain Aggregate Function Context {H16210} <S20200>
  4000. **
  4001. ** The implementation of aggregate SQL functions use this routine to allocate
  4002. ** a structure for storing their state.
  4003. **
  4004. ** The first time the sqlite3_aggregate_context() routine is called for a
  4005. ** particular aggregate, SQLite allocates nBytes of memory, zeroes out that
  4006. ** memory, and returns a pointer to it. On second and subsequent calls to
  4007. ** sqlite3_aggregate_context() for the same aggregate function index,
  4008. ** the same buffer is returned. The implementation of the aggregate can use
  4009. ** the returned buffer to accumulate data.
  4010. **
  4011. ** SQLite automatically frees the allocated buffer when the aggregate
  4012. ** query concludes.
  4013. **
  4014. ** The first parameter should be a copy of the
  4015. ** [sqlite3_context | SQL function context] that is the first parameter
  4016. ** to the callback routine that implements the aggregate function.
  4017. **
  4018. ** This routine must be called from the same thread in which
  4019. ** the aggregate SQL function is running.
  4020. **
  4021. ** INVARIANTS:
  4022. **
  4023. ** {H16211} The first invocation of [sqlite3_aggregate_context(C,N)] for
  4024. ** a particular instance of an aggregate function (for a particular
  4025. ** context C) causes SQLite to allocate N bytes of memory,
  4026. ** zero that memory, and return a pointer to the allocated memory.
  4027. **
  4028. ** {H16213} If a memory allocation error occurs during
  4029. ** [sqlite3_aggregate_context(C,N)] then the function returns 0.
  4030. **
  4031. ** {H16215} Second and subsequent invocations of
  4032. ** [sqlite3_aggregate_context(C,N)] for the same context pointer C
  4033. ** ignore the N parameter and return a pointer to the same
  4034. ** block of memory returned by the first invocation.
  4035. **
  4036. ** {H16217} The memory allocated by [sqlite3_aggregate_context(C,N)] is
  4037. ** automatically freed on the next call to [sqlite3_reset()]
  4038. ** or [sqlite3_finalize()] for the [prepared statement] containing
  4039. ** the aggregate function associated with context C.
  4040. */
  4041. void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
  4042. /*
  4043. ** CAPI3REF: User Data For Functions {H16240} <S20200>
  4044. **
  4045. ** The sqlite3_user_data() interface returns a copy of
  4046. ** the pointer that was the pUserData parameter (the 5th parameter)
  4047. ** of the [sqlite3_create_function()]
  4048. ** and [sqlite3_create_function16()] routines that originally
  4049. ** registered the application defined function. {END}
  4050. **
  4051. ** This routine must be called from the same thread in which
  4052. ** the application-defined function is running.
  4053. **
  4054. ** INVARIANTS:
  4055. **
  4056. ** {H16243} The [sqlite3_user_data(C)] interface returns a copy of the
  4057. ** P pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)]
  4058. ** or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that
  4059. ** registered the SQL function associated with [sqlite3_context] C.
  4060. */
  4061. void *sqlite3_user_data(sqlite3_context*);
  4062. /*
  4063. ** CAPI3REF: Database Connection For Functions {H16250} <S60600><S20200>
  4064. **
  4065. ** The sqlite3_context_db_handle() interface returns a copy of
  4066. ** the pointer to the [database connection] (the 1st parameter)
  4067. ** of the [sqlite3_create_function()]
  4068. ** and [sqlite3_create_function16()] routines that originally
  4069. ** registered the application defined function.
  4070. **
  4071. ** INVARIANTS:
  4072. **
  4073. ** {H16253} The [sqlite3_context_db_handle(C)] interface returns a copy of the
  4074. ** D pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)]
  4075. ** or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that
  4076. ** registered the SQL function associated with [sqlite3_context] C.
  4077. */
  4078. sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
  4079. /*
  4080. ** CAPI3REF: Function Auxiliary Data {H16270} <S20200>
  4081. **
  4082. ** The following two functions may be used by scalar SQL functions to
  4083. ** associate metadata with argument values. If the same value is passed to
  4084. ** multiple invocations of the same SQL function during query execution, under
  4085. ** some circumstances the associated metadata may be preserved. This may
  4086. ** be used, for example, to add a regular-expression matching scalar
  4087. ** function. The compiled version of the regular expression is stored as
  4088. ** metadata associated with the SQL value passed as the regular expression
  4089. ** pattern. The compiled regular expression can be reused on multiple
  4090. ** invocations of the same function so that the original pattern string
  4091. ** does not need to be recompiled on each invocation.
  4092. **
  4093. ** The sqlite3_get_auxdata() interface returns a pointer to the metadata
  4094. ** associated by the sqlite3_set_auxdata() function with the Nth argument
  4095. ** value to the application-defined function. If no metadata has been ever
  4096. ** been set for the Nth argument of the function, or if the corresponding
  4097. ** function parameter has changed since the meta-data was set,
  4098. ** then sqlite3_get_auxdata() returns a NULL pointer.
  4099. **
  4100. ** The sqlite3_set_auxdata() interface saves the metadata
  4101. ** pointed to by its 3rd parameter as the metadata for the N-th
  4102. ** argument of the application-defined function. Subsequent
  4103. ** calls to sqlite3_get_auxdata() might return this data, if it has
  4104. ** not been destroyed.
  4105. ** If it is not NULL, SQLite will invoke the destructor
  4106. ** function given by the 4th parameter to sqlite3_set_auxdata() on
  4107. ** the metadata when the corresponding function parameter changes
  4108. ** or when the SQL statement completes, whichever comes first.
  4109. **
  4110. ** SQLite is free to call the destructor and drop metadata on any
  4111. ** parameter of any function at any time. The only guarantee is that
  4112. ** the destructor will be called before the metadata is dropped.
  4113. **
  4114. ** In practice, metadata is preserved between function calls for
  4115. ** expressions that are constant at compile time. This includes literal
  4116. ** values and SQL variables.
  4117. **
  4118. ** These routines must be called from the same thread in which
  4119. ** the SQL function is running.
  4120. **
  4121. ** INVARIANTS:
  4122. **
  4123. ** {H16272} The [sqlite3_get_auxdata(C,N)] interface returns a pointer
  4124. ** to metadata associated with the Nth parameter of the SQL function
  4125. ** whose context is C, or NULL if there is no metadata associated
  4126. ** with that parameter.
  4127. **
  4128. ** {H16274} The [sqlite3_set_auxdata(C,N,P,D)] interface assigns a metadata
  4129. ** pointer P to the Nth parameter of the SQL function with context C.
  4130. **
  4131. ** {H16276} SQLite will invoke the destructor D with a single argument
  4132. ** which is the metadata pointer P following a call to
  4133. ** [sqlite3_set_auxdata(C,N,P,D)] when SQLite ceases to hold
  4134. ** the metadata.
  4135. **
  4136. ** {H16277} SQLite ceases to hold metadata for an SQL function parameter
  4137. ** when the value of that parameter changes.
  4138. **
  4139. ** {H16278} When [sqlite3_set_auxdata(C,N,P,D)] is invoked, the destructor
  4140. ** is called for any prior metadata associated with the same function
  4141. ** context C and parameter N.
  4142. **
  4143. ** {H16279} SQLite will call destructors for any metadata it is holding
  4144. ** in a particular [prepared statement] S when either
  4145. ** [sqlite3_reset(S)] or [sqlite3_finalize(S)] is called.
  4146. */
  4147. void *sqlite3_get_auxdata(sqlite3_context*, int N);
  4148. void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
  4149. /*
  4150. ** CAPI3REF: Constants Defining Special Destructor Behavior {H10280} <S30100>
  4151. **
  4152. ** These are special values for the destructor that is passed in as the
  4153. ** final argument to routines like [sqlite3_result_blob()]. If the destructor
  4154. ** argument is SQLITE_STATIC, it means that the content pointer is constant
  4155. ** and will never change. It does not need to be destroyed. The
  4156. ** SQLITE_TRANSIENT value means that the content will likely change in
  4157. ** the near future and that SQLite should make its own private copy of
  4158. ** the content before returning.
  4159. **
  4160. ** The typedef is necessary to work around problems in certain
  4161. ** C++ compilers. See ticket #2191.
  4162. */
  4163. typedef void (*sqlite3_destructor_type)(void*);
  4164. #define SQLITE_STATIC ((sqlite3_destructor_type)0)
  4165. #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
  4166. /*
  4167. ** CAPI3REF: Setting The Result Of An SQL Function {H16400} <S20200>
  4168. **
  4169. ** These routines are used by the xFunc or xFinal callbacks that
  4170. ** implement SQL functions and aggregates. See
  4171. ** [sqlite3_create_function()] and [sqlite3_create_function16()]
  4172. ** for additional information.
  4173. **
  4174. ** These functions work very much like the [parameter binding] family of
  4175. ** functions used to bind values to host parameters in prepared statements.
  4176. ** Refer to the [SQL parameter] documentation for additional information.
  4177. **
  4178. ** The sqlite3_result_blob() interface sets the result from
  4179. ** an application-defined function to be the BLOB whose content is pointed
  4180. ** to by the second parameter and which is N bytes long where N is the
  4181. ** third parameter.
  4182. **
  4183. ** The sqlite3_result_zeroblob() interfaces set the result of
  4184. ** the application-defined function to be a BLOB containing all zero
  4185. ** bytes and N bytes in size, where N is the value of the 2nd parameter.
  4186. **
  4187. ** The sqlite3_result_double() interface sets the result from
  4188. ** an application-defined function to be a floating point value specified
  4189. ** by its 2nd argument.
  4190. **
  4191. ** The sqlite3_result_error() and sqlite3_result_error16() functions
  4192. ** cause the implemented SQL function to throw an exception.
  4193. ** SQLite uses the string pointed to by the
  4194. ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
  4195. ** as the text of an error message. SQLite interprets the error
  4196. ** message string from sqlite3_result_error() as UTF-8. SQLite
  4197. ** interprets the string from sqlite3_result_error16() as UTF-16 in native
  4198. ** byte order. If the third parameter to sqlite3_result_error()
  4199. ** or sqlite3_result_error16() is negative then SQLite takes as the error
  4200. ** message all text up through the first zero character.
  4201. ** If the third parameter to sqlite3_result_error() or
  4202. ** sqlite3_result_error16() is non-negative then SQLite takes that many
  4203. ** bytes (not characters) from the 2nd parameter as the error message.
  4204. ** The sqlite3_result_error() and sqlite3_result_error16()
  4205. ** routines make a private copy of the error message text before
  4206. ** they return. Hence, the calling function can deallocate or
  4207. ** modify the text after they return without harm.
  4208. ** The sqlite3_result_error_code() function changes the error code
  4209. ** returned by SQLite as a result of an error in a function. By default,
  4210. ** the error code is SQLITE_ERROR. A subsequent call to sqlite3_result_error()
  4211. ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
  4212. **
  4213. ** The sqlite3_result_toobig() interface causes SQLite to throw an error
  4214. ** indicating that a string or BLOB is to long to represent.
  4215. **
  4216. ** The sqlite3_result_nomem() interface causes SQLite to throw an error
  4217. ** indicating that a memory allocation failed.
  4218. **
  4219. ** The sqlite3_result_int() interface sets the return value
  4220. ** of the application-defined function to be the 32-bit signed integer
  4221. ** value given in the 2nd argument.
  4222. ** The sqlite3_result_int64() interface sets the return value
  4223. ** of the application-defined function to be the 64-bit signed integer
  4224. ** value given in the 2nd argument.
  4225. **
  4226. ** The sqlite3_result_null() interface sets the return value
  4227. ** of the application-defined function to be NULL.
  4228. **
  4229. ** The sqlite3_result_text(), sqlite3_result_text16(),
  4230. ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
  4231. ** set the return value of the application-defined function to be
  4232. ** a text string which is represented as UTF-8, UTF-16 native byte order,
  4233. ** UTF-16 little endian, or UTF-16 big endian, respectively.
  4234. ** SQLite takes the text result from the application from
  4235. ** the 2nd parameter of the sqlite3_result_text* interfaces.
  4236. ** If the 3rd parameter to the sqlite3_result_text* interfaces
  4237. ** is negative, then SQLite takes result text from the 2nd parameter
  4238. ** through the first zero character.
  4239. ** If the 3rd parameter to the sqlite3_result_text* interfaces
  4240. ** is non-negative, then as many bytes (not characters) of the text
  4241. ** pointed to by the 2nd parameter are taken as the application-defined
  4242. ** function result.
  4243. ** If the 4th parameter to the sqlite3_result_text* interfaces
  4244. ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
  4245. ** function as the destructor on the text or BLOB result when it has
  4246. ** finished using that result.
  4247. ** If the 4th parameter to the sqlite3_result_text* interfaces or
  4248. ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
  4249. ** assumes that the text or BLOB result is in constant space and does not
  4250. ** copy the it or call a destructor when it has finished using that result.
  4251. ** If the 4th parameter to the sqlite3_result_text* interfaces
  4252. ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
  4253. ** then SQLite makes a copy of the result into space obtained from
  4254. ** from [sqlite3_malloc()] before it returns.
  4255. **
  4256. ** The sqlite3_result_value() interface sets the result of
  4257. ** the application-defined function to be a copy the
  4258. ** [unprotected sqlite3_value] object specified by the 2nd parameter. The
  4259. ** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
  4260. ** so that the [sqlite3_value] specified in the parameter may change or
  4261. ** be deallocated after sqlite3_result_value() returns without harm.
  4262. ** A [protected sqlite3_value] object may always be used where an
  4263. ** [unprotected sqlite3_value] object is required, so either
  4264. ** kind of [sqlite3_value] object can be used with this interface.
  4265. **
  4266. ** If these routines are called from within the different thread
  4267. ** than the one containing the application-defined function that received
  4268. ** the [sqlite3_context] pointer, the results are undefined.
  4269. **
  4270. ** INVARIANTS:
  4271. **
  4272. ** {H16403} The default return value from any SQL function is NULL.
  4273. **
  4274. ** {H16406} The [sqlite3_result_blob(C,V,N,D)] interface changes the
  4275. ** return value of function C to be a BLOB that is N bytes
  4276. ** in length and with content pointed to by V.
  4277. **
  4278. ** {H16409} The [sqlite3_result_double(C,V)] interface changes the
  4279. ** return value of function C to be the floating point value V.
  4280. **
  4281. ** {H16412} The [sqlite3_result_error(C,V,N)] interface changes the return
  4282. ** value of function C to be an exception with error code
  4283. ** [SQLITE_ERROR] and a UTF-8 error message copied from V up to the
  4284. ** first zero byte or until N bytes are read if N is positive.
  4285. **
  4286. ** {H16415} The [sqlite3_result_error16(C,V,N)] interface changes the return
  4287. ** value of function C to be an exception with error code
  4288. ** [SQLITE_ERROR] and a UTF-16 native byte order error message
  4289. ** copied from V up to the first zero terminator or until N bytes
  4290. ** are read if N is positive.
  4291. **
  4292. ** {H16418} The [sqlite3_result_error_toobig(C)] interface changes the return
  4293. ** value of the function C to be an exception with error code
  4294. ** [SQLITE_TOOBIG] and an appropriate error message.
  4295. **
  4296. ** {H16421} The [sqlite3_result_error_nomem(C)] interface changes the return
  4297. ** value of the function C to be an exception with error code
  4298. ** [SQLITE_NOMEM] and an appropriate error message.
  4299. **
  4300. ** {H16424} The [sqlite3_result_error_code(C,E)] interface changes the return
  4301. ** value of the function C to be an exception with error code E.
  4302. ** The error message text is unchanged.
  4303. **
  4304. ** {H16427} The [sqlite3_result_int(C,V)] interface changes the
  4305. ** return value of function C to be the 32-bit integer value V.
  4306. **
  4307. ** {H16430} The [sqlite3_result_int64(C,V)] interface changes the
  4308. ** return value of function C to be the 64-bit integer value V.
  4309. **
  4310. ** {H16433} The [sqlite3_result_null(C)] interface changes the
  4311. ** return value of function C to be NULL.
  4312. **
  4313. ** {H16436} The [sqlite3_result_text(C,V,N,D)] interface changes the
  4314. ** return value of function C to be the UTF-8 string
  4315. ** V up to the first zero if N is negative
  4316. ** or the first N bytes of V if N is non-negative.
  4317. **
  4318. ** {H16439} The [sqlite3_result_text16(C,V,N,D)] interface changes the
  4319. ** return value of function C to be the UTF-16 native byte order
  4320. ** string V up to the first zero if N is negative
  4321. ** or the first N bytes of V if N is non-negative.
  4322. **
  4323. ** {H16442} The [sqlite3_result_text16be(C,V,N,D)] interface changes the
  4324. ** return value of function C to be the UTF-16 big-endian
  4325. ** string V up to the first zero if N is negative
  4326. ** or the first N bytes or V if N is non-negative.
  4327. **
  4328. ** {H16445} The [sqlite3_result_text16le(C,V,N,D)] interface changes the
  4329. ** return value of function C to be the UTF-16 little-endian
  4330. ** string V up to the first zero if N is negative
  4331. ** or the first N bytes of V if N is non-negative.
  4332. **
  4333. ** {H16448} The [sqlite3_result_value(C,V)] interface changes the
  4334. ** return value of function C to be the [unprotected sqlite3_value]
  4335. ** object V.
  4336. **
  4337. ** {H16451} The [sqlite3_result_zeroblob(C,N)] interface changes the
  4338. ** return value of function C to be an N-byte BLOB of all zeros.
  4339. **
  4340. ** {H16454} The [sqlite3_result_error()] and [sqlite3_result_error16()]
  4341. ** interfaces make a copy of their error message strings before
  4342. ** returning.
  4343. **
  4344. ** {H16457} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
  4345. ** [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
  4346. ** [sqlite3_result_text16be(C,V,N,D)], or
  4347. ** [sqlite3_result_text16le(C,V,N,D)] is the constant [SQLITE_STATIC]
  4348. ** then no destructor is ever called on the pointer V and SQLite
  4349. ** assumes that V is immutable.
  4350. **
  4351. ** {H16460} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
  4352. ** [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
  4353. ** [sqlite3_result_text16be(C,V,N,D)], or
  4354. ** [sqlite3_result_text16le(C,V,N,D)] is the constant
  4355. ** [SQLITE_TRANSIENT] then the interfaces makes a copy of the
  4356. ** content of V and retains the copy.
  4357. **
  4358. ** {H16463} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)],
  4359. ** [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)],
  4360. ** [sqlite3_result_text16be(C,V,N,D)], or
  4361. ** [sqlite3_result_text16le(C,V,N,D)] is some value other than
  4362. ** the constants [SQLITE_STATIC] and [SQLITE_TRANSIENT] then
  4363. ** SQLite will invoke the destructor D with V as its only argument
  4364. ** when it has finished with the V value.
  4365. */
  4366. void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
  4367. void sqlite3_result_double(sqlite3_context*, double);
  4368. void sqlite3_result_error(sqlite3_context*, const char*, int);
  4369. void sqlite3_result_error16(sqlite3_context*, const void*, int);
  4370. void sqlite3_result_error_toobig(sqlite3_context*);
  4371. void sqlite3_result_error_nomem(sqlite3_context*);
  4372. void sqlite3_result_error_code(sqlite3_context*, int);
  4373. void sqlite3_result_int(sqlite3_context*, int);
  4374. void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
  4375. void sqlite3_result_null(sqlite3_context*);
  4376. void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
  4377. void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
  4378. void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
  4379. void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
  4380. void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
  4381. void sqlite3_result_zeroblob(sqlite3_context*, int n);
  4382. /*
  4383. ** CAPI3REF: Define New Collating Sequences {H16600} <S20300>
  4384. **
  4385. ** These functions are used to add new collation sequences to the
  4386. ** [database connection] specified as the first argument.
  4387. **
  4388. ** The name of the new collation sequence is specified as a UTF-8 string
  4389. ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
  4390. ** and a UTF-16 string for sqlite3_create_collation16(). In all cases
  4391. ** the name is passed as the second function argument.
  4392. **
  4393. ** The third argument may be one of the constants [SQLITE_UTF8],
  4394. ** [SQLITE_UTF16LE] or [SQLITE_UTF16BE], indicating that the user-supplied
  4395. ** routine expects to be passed pointers to strings encoded using UTF-8,
  4396. ** UTF-16 little-endian, or UTF-16 big-endian, respectively. The
  4397. ** third argument might also be [SQLITE_UTF16_ALIGNED] to indicate that
  4398. ** the routine expects pointers to 16-bit word aligned strings
  4399. ** of UTF-16 in the native byte order of the host computer.
  4400. **
  4401. ** A pointer to the user supplied routine must be passed as the fifth
  4402. ** argument. If it is NULL, this is the same as deleting the collation
  4403. ** sequence (so that SQLite cannot call it anymore).
  4404. ** Each time the application supplied function is invoked, it is passed
  4405. ** as its first parameter a copy of the void* passed as the fourth argument
  4406. ** to sqlite3_create_collation() or sqlite3_create_collation16().
  4407. **
  4408. ** The remaining arguments to the application-supplied routine are two strings,
  4409. ** each represented by a (length, data) pair and encoded in the encoding
  4410. ** that was passed as the third argument when the collation sequence was
  4411. ** registered. {END} The application defined collation routine should
  4412. ** return negative, zero or positive if the first string is less than,
  4413. ** equal to, or greater than the second string. i.e. (STRING1 - STRING2).
  4414. **
  4415. ** The sqlite3_create_collation_v2() works like sqlite3_create_collation()
  4416. ** except that it takes an extra argument which is a destructor for
  4417. ** the collation. The destructor is called when the collation is
  4418. ** destroyed and is passed a copy of the fourth parameter void* pointer
  4419. ** of the sqlite3_create_collation_v2().
  4420. ** Collations are destroyed when they are overridden by later calls to the
  4421. ** collation creation functions or when the [database connection] is closed
  4422. ** using [sqlite3_close()].
  4423. **
  4424. ** INVARIANTS:
  4425. **
  4426. ** {H16603} A successful call to the
  4427. ** [sqlite3_create_collation_v2(B,X,E,P,F,D)] interface
  4428. ** registers function F as the comparison function used to
  4429. ** implement collation X on the [database connection] B for
  4430. ** databases having encoding E.
  4431. **
  4432. ** {H16604} SQLite understands the X parameter to
  4433. ** [sqlite3_create_collation_v2(B,X,E,P,F,D)] as a zero-terminated
  4434. ** UTF-8 string in which case is ignored for ASCII characters and
  4435. ** is significant for non-ASCII characters.
  4436. **
  4437. ** {H16606} Successive calls to [sqlite3_create_collation_v2(B,X,E,P,F,D)]
  4438. ** with the same values for B, X, and E, override prior values
  4439. ** of P, F, and D.
  4440. **
  4441. ** {H16609} If the destructor D in [sqlite3_create_collation_v2(B,X,E,P,F,D)]
  4442. ** is not NULL then it is called with argument P when the
  4443. ** collating function is dropped by SQLite.
  4444. **
  4445. ** {H16612} A collating function is dropped when it is overloaded.
  4446. **
  4447. ** {H16615} A collating function is dropped when the database connection
  4448. ** is closed using [sqlite3_close()].
  4449. **
  4450. ** {H16618} The pointer P in [sqlite3_create_collation_v2(B,X,E,P,F,D)]
  4451. ** is passed through as the first parameter to the comparison
  4452. ** function F for all subsequent invocations of F.
  4453. **
  4454. ** {H16621} A call to [sqlite3_create_collation(B,X,E,P,F)] is exactly
  4455. ** the same as a call to [sqlite3_create_collation_v2()] with
  4456. ** the same parameters and a NULL destructor.
  4457. **
  4458. ** {H16624} Following a [sqlite3_create_collation_v2(B,X,E,P,F,D)],
  4459. ** SQLite uses the comparison function F for all text comparison
  4460. ** operations on the [database connection] B on text values that
  4461. ** use the collating sequence named X.
  4462. **
  4463. ** {H16627} The [sqlite3_create_collation16(B,X,E,P,F)] works the same
  4464. ** as [sqlite3_create_collation(B,X,E,P,F)] except that the
  4465. ** collation name X is understood as UTF-16 in native byte order
  4466. ** instead of UTF-8.
  4467. **
  4468. ** {H16630} When multiple comparison functions are available for the same
  4469. ** collating sequence, SQLite chooses the one whose text encoding
  4470. ** requires the least amount of conversion from the default
  4471. ** text encoding of the database.
  4472. */
  4473. int sqlite3_create_collation(
  4474. sqlite3*,
  4475. const char *zName,
  4476. int eTextRep,
  4477. void*,
  4478. int(*xCompare)(void*,int,const void*,int,const void*)
  4479. );
  4480. int sqlite3_create_collation_v2(
  4481. sqlite3*,
  4482. const char *zName,
  4483. int eTextRep,
  4484. void*,
  4485. int(*xCompare)(void*,int,const void*,int,const void*),
  4486. void(*xDestroy)(void*)
  4487. );
  4488. int sqlite3_create_collation16(
  4489. sqlite3*,
  4490. const void *zName,
  4491. int eTextRep,
  4492. void*,
  4493. int(*xCompare)(void*,int,const void*,int,const void*)
  4494. );
  4495. /*
  4496. ** CAPI3REF: Collation Needed Callbacks {H16700} <S20300>
  4497. **
  4498. ** To avoid having to register all collation sequences before a database
  4499. ** can be used, a single callback function may be registered with the
  4500. ** [database connection] to be called whenever an undefined collation
  4501. ** sequence is required.
  4502. **
  4503. ** If the function is registered using the sqlite3_collation_needed() API,
  4504. ** then it is passed the names of undefined collation sequences as strings
  4505. ** encoded in UTF-8. {H16703} If sqlite3_collation_needed16() is used,
  4506. ** the names are passed as UTF-16 in machine native byte order.
  4507. ** A call to either function replaces any existing callback.
  4508. **
  4509. ** When the callback is invoked, the first argument passed is a copy
  4510. ** of the second argument to sqlite3_collation_needed() or
  4511. ** sqlite3_collation_needed16(). The second argument is the database
  4512. ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
  4513. ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
  4514. ** sequence function required. The fourth parameter is the name of the
  4515. ** required collation sequence.
  4516. **
  4517. ** The callback function should register the desired collation using
  4518. ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
  4519. ** [sqlite3_create_collation_v2()].
  4520. **
  4521. ** INVARIANTS:
  4522. **
  4523. ** {H16702} A successful call to [sqlite3_collation_needed(D,P,F)]
  4524. ** or [sqlite3_collation_needed16(D,P,F)] causes
  4525. ** the [database connection] D to invoke callback F with first
  4526. ** parameter P whenever it needs a comparison function for a
  4527. ** collating sequence that it does not know about.
  4528. **
  4529. ** {H16704} Each successful call to [sqlite3_collation_needed()] or
  4530. ** [sqlite3_collation_needed16()] overrides the callback registered
  4531. ** on the same [database connection] by prior calls to either
  4532. ** interface.
  4533. **
  4534. ** {H16706} The name of the requested collating function passed in the
  4535. ** 4th parameter to the callback is in UTF-8 if the callback
  4536. ** was registered using [sqlite3_collation_needed()] and
  4537. ** is in UTF-16 native byte order if the callback was
  4538. ** registered using [sqlite3_collation_needed16()].
  4539. */
  4540. int sqlite3_collation_needed(
  4541. sqlite3*,
  4542. void*,
  4543. void(*)(void*,sqlite3*,int eTextRep,const char*)
  4544. );
  4545. int sqlite3_collation_needed16(
  4546. sqlite3*,
  4547. void*,
  4548. void(*)(void*,sqlite3*,int eTextRep,const void*)
  4549. );
  4550. /*
  4551. ** Specify the key for an encrypted database. This routine should be
  4552. ** called right after sqlite3_open().
  4553. **
  4554. ** The code to implement this API is not available in the public release
  4555. ** of SQLite.
  4556. */
  4557. int sqlite3_key(
  4558. sqlite3 *db, /* Database to be rekeyed */
  4559. const void *pKey, int nKey /* The key */
  4560. );
  4561. /*
  4562. ** Change the key on an open database. If the current database is not
  4563. ** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
  4564. ** database is decrypted.
  4565. **
  4566. ** The code to implement this API is not available in the public release
  4567. ** of SQLite.
  4568. */
  4569. int sqlite3_rekey(
  4570. sqlite3 *db, /* Database to be rekeyed */
  4571. const void *pKey, int nKey /* The new key */
  4572. );
  4573. /*
  4574. ** CAPI3REF: Suspend Execution For A Short Time {H10530} <S40410>
  4575. **
  4576. ** The sqlite3_sleep() function causes the current thread to suspend execution
  4577. ** for at least a number of milliseconds specified in its parameter.
  4578. **
  4579. ** If the operating system does not support sleep requests with
  4580. ** millisecond time resolution, then the time will be rounded up to
  4581. ** the nearest second. The number of milliseconds of sleep actually
  4582. ** requested from the operating system is returned.
  4583. **
  4584. ** SQLite implements this interface by calling the xSleep()
  4585. ** method of the default [sqlite3_vfs] object.
  4586. **
  4587. ** INVARIANTS:
  4588. **
  4589. ** {H10533} The [sqlite3_sleep(M)] interface invokes the xSleep
  4590. ** method of the default [sqlite3_vfs|VFS] in order to
  4591. ** suspend execution of the current thread for at least
  4592. ** M milliseconds.
  4593. **
  4594. ** {H10536} The [sqlite3_sleep(M)] interface returns the number of
  4595. ** milliseconds of sleep actually requested of the operating
  4596. ** system, which might be larger than the parameter M.
  4597. */
  4598. int sqlite3_sleep(int);
  4599. /*
  4600. ** CAPI3REF: Name Of The Folder Holding Temporary Files {H10310} <S20000>
  4601. **
  4602. ** If this global variable is made to point to a string which is
  4603. ** the name of a folder (a.k.a. directory), then all temporary files
  4604. ** created by SQLite will be placed in that directory. If this variable
  4605. ** is a NULL pointer, then SQLite performs a search for an appropriate
  4606. ** temporary file directory.
  4607. **
  4608. ** It is not safe to modify this variable once a [database connection]
  4609. ** has been opened. It is intended that this variable be set once
  4610. ** as part of process initialization and before any SQLite interface
  4611. ** routines have been call and remain unchanged thereafter.
  4612. */
  4613. SQLITE_EXTERN char *sqlite3_temp_directory;
  4614. /*
  4615. ** CAPI3REF: Test For Auto-Commit Mode {H12930} <S60200>
  4616. ** KEYWORDS: {autocommit mode}
  4617. **
  4618. ** The sqlite3_get_autocommit() interface returns non-zero or
  4619. ** zero if the given database connection is or is not in autocommit mode,
  4620. ** respectively. Autocommit mode is on by default.
  4621. ** Autocommit mode is disabled by a [BEGIN] statement.
  4622. ** Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
  4623. **
  4624. ** If certain kinds of errors occur on a statement within a multi-statement
  4625. ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
  4626. ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
  4627. ** transaction might be rolled back automatically. The only way to
  4628. ** find out whether SQLite automatically rolled back the transaction after
  4629. ** an error is to use this function.
  4630. **
  4631. ** INVARIANTS:
  4632. **
  4633. ** {H12931} The [sqlite3_get_autocommit(D)] interface returns non-zero or
  4634. ** zero if the [database connection] D is or is not in autocommit
  4635. ** mode, respectively.
  4636. **
  4637. ** {H12932} Autocommit mode is on by default.
  4638. **
  4639. ** {H12933} Autocommit mode is disabled by a successful [BEGIN] statement.
  4640. **
  4641. ** {H12934} Autocommit mode is enabled by a successful [COMMIT] or [ROLLBACK]
  4642. ** statement.
  4643. **
  4644. ** ASSUMPTIONS:
  4645. **
  4646. ** {A12936} If another thread changes the autocommit status of the database
  4647. ** connection while this routine is running, then the return value
  4648. ** is undefined.
  4649. */
  4650. int sqlite3_get_autocommit(sqlite3*);
  4651. /*
  4652. ** CAPI3REF: Find The Database Handle Of A Prepared Statement {H13120} <S60600>
  4653. **
  4654. ** The sqlite3_db_handle interface returns the [database connection] handle
  4655. ** to which a [prepared statement] belongs. The database handle returned by
  4656. ** sqlite3_db_handle is the same database handle that was the first argument
  4657. ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
  4658. ** create the statement in the first place.
  4659. **
  4660. ** INVARIANTS:
  4661. **
  4662. ** {H13123} The [sqlite3_db_handle(S)] interface returns a pointer
  4663. ** to the [database connection] associated with the
  4664. ** [prepared statement] S.
  4665. */
  4666. sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
  4667. /*
  4668. ** CAPI3REF: Find the next prepared statement {H13140} <S60600>
  4669. **
  4670. ** This interface returns a pointer to the next [prepared statement] after
  4671. ** pStmt associated with the [database connection] pDb. If pStmt is NULL
  4672. ** then this interface returns a pointer to the first prepared statement
  4673. ** associated with the database connection pDb. If no prepared statement
  4674. ** satisfies the conditions of this routine, it returns NULL.
  4675. **
  4676. ** INVARIANTS:
  4677. **
  4678. ** {H13143} If D is a [database connection] that holds one or more
  4679. ** unfinalized [prepared statements] and S is a NULL pointer,
  4680. ** then [sqlite3_next_stmt(D, S)] routine shall return a pointer
  4681. ** to one of the prepared statements associated with D.
  4682. **
  4683. ** {H13146} If D is a [database connection] that holds no unfinalized
  4684. ** [prepared statements] and S is a NULL pointer, then
  4685. ** [sqlite3_next_stmt(D, S)] routine shall return a NULL pointer.
  4686. **
  4687. ** {H13149} If S is a [prepared statement] in the [database connection] D
  4688. ** and S is not the last prepared statement in D, then
  4689. ** [sqlite3_next_stmt(D, S)] routine shall return a pointer
  4690. ** to the next prepared statement in D after S.
  4691. **
  4692. ** {H13152} If S is the last [prepared statement] in the
  4693. ** [database connection] D then the [sqlite3_next_stmt(D, S)]
  4694. ** routine shall return a NULL pointer.
  4695. **
  4696. ** ASSUMPTIONS:
  4697. **
  4698. ** {A13154} The [database connection] pointer D in a call to
  4699. ** [sqlite3_next_stmt(D,S)] must refer to an open database
  4700. ** connection and in particular must not be a NULL pointer.
  4701. */
  4702. sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
  4703. /*
  4704. ** CAPI3REF: Commit And Rollback Notification Callbacks {H12950} <S60400>
  4705. **
  4706. ** The sqlite3_commit_hook() interface registers a callback
  4707. ** function to be invoked whenever a transaction is committed.
  4708. ** Any callback set by a previous call to sqlite3_commit_hook()
  4709. ** for the same database connection is overridden.
  4710. ** The sqlite3_rollback_hook() interface registers a callback
  4711. ** function to be invoked whenever a transaction is committed.
  4712. ** Any callback set by a previous call to sqlite3_commit_hook()
  4713. ** for the same database connection is overridden.
  4714. ** The pArg argument is passed through to the callback.
  4715. ** If the callback on a commit hook function returns non-zero,
  4716. ** then the commit is converted into a rollback.
  4717. **
  4718. ** If another function was previously registered, its
  4719. ** pArg value is returned. Otherwise NULL is returned.
  4720. **
  4721. ** Registering a NULL function disables the callback.
  4722. **
  4723. ** For the purposes of this API, a transaction is said to have been
  4724. ** rolled back if an explicit "ROLLBACK" statement is executed, or
  4725. ** an error or constraint causes an implicit rollback to occur.
  4726. ** The rollback callback is not invoked if a transaction is
  4727. ** automatically rolled back because the database connection is closed.
  4728. ** The rollback callback is not invoked if a transaction is
  4729. ** rolled back because a commit callback returned non-zero.
  4730. ** <todo> Check on this </todo>
  4731. **
  4732. ** INVARIANTS:
  4733. **
  4734. ** {H12951} The [sqlite3_commit_hook(D,F,P)] interface registers the
  4735. ** callback function F to be invoked with argument P whenever
  4736. ** a transaction commits on the [database connection] D.
  4737. **
  4738. ** {H12952} The [sqlite3_commit_hook(D,F,P)] interface returns the P argument
  4739. ** from the previous call with the same [database connection] D,
  4740. ** or NULL on the first call for a particular database connection D.
  4741. **
  4742. ** {H12953} Each call to [sqlite3_commit_hook()] overwrites the callback
  4743. ** registered by prior calls.
  4744. **
  4745. ** {H12954} If the F argument to [sqlite3_commit_hook(D,F,P)] is NULL
  4746. ** then the commit hook callback is canceled and no callback
  4747. ** is invoked when a transaction commits.
  4748. **
  4749. ** {H12955} If the commit callback returns non-zero then the commit is
  4750. ** converted into a rollback.
  4751. **
  4752. ** {H12961} The [sqlite3_rollback_hook(D,F,P)] interface registers the
  4753. ** callback function F to be invoked with argument P whenever
  4754. ** a transaction rolls back on the [database connection] D.
  4755. **
  4756. ** {H12962} The [sqlite3_rollback_hook(D,F,P)] interface returns the P
  4757. ** argument from the previous call with the same
  4758. ** [database connection] D, or NULL on the first call
  4759. ** for a particular database connection D.
  4760. **
  4761. ** {H12963} Each call to [sqlite3_rollback_hook()] overwrites the callback
  4762. ** registered by prior calls.
  4763. **
  4764. ** {H12964} If the F argument to [sqlite3_rollback_hook(D,F,P)] is NULL
  4765. ** then the rollback hook callback is canceled and no callback
  4766. ** is invoked when a transaction rolls back.
  4767. */
  4768. void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
  4769. void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
  4770. /*
  4771. ** CAPI3REF: Data Change Notification Callbacks {H12970} <S60400>
  4772. **
  4773. ** The sqlite3_update_hook() interface registers a callback function
  4774. ** with the [database connection] identified by the first argument
  4775. ** to be invoked whenever a row is updated, inserted or deleted.
  4776. ** Any callback set by a previous call to this function
  4777. ** for the same database connection is overridden.
  4778. **
  4779. ** The second argument is a pointer to the function to invoke when a
  4780. ** row is updated, inserted or deleted.
  4781. ** The first argument to the callback is a copy of the third argument
  4782. ** to sqlite3_update_hook().
  4783. ** The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
  4784. ** or [SQLITE_UPDATE], depending on the operation that caused the callback
  4785. ** to be invoked.
  4786. ** The third and fourth arguments to the callback contain pointers to the
  4787. ** database and table name containing the affected row.
  4788. ** The final callback parameter is the rowid of the row. In the case of
  4789. ** an update, this is the rowid after the update takes place.
  4790. **
  4791. ** The update hook is not invoked when internal system tables are
  4792. ** modified (i.e. sqlite_master and sqlite_sequence).
  4793. **
  4794. ** If another function was previously registered, its pArg value
  4795. ** is returned. Otherwise NULL is returned.
  4796. **
  4797. ** INVARIANTS:
  4798. **
  4799. ** {H12971} The [sqlite3_update_hook(D,F,P)] interface causes the callback
  4800. ** function F to be invoked with first parameter P whenever
  4801. ** a table row is modified, inserted, or deleted on
  4802. ** the [database connection] D.
  4803. **
  4804. ** {H12973} The [sqlite3_update_hook(D,F,P)] interface returns the value
  4805. ** of P for the previous call on the same [database connection] D,
  4806. ** or NULL for the first call.
  4807. **
  4808. ** {H12975} If the update hook callback F in [sqlite3_update_hook(D,F,P)]
  4809. ** is NULL then the no update callbacks are made.
  4810. **
  4811. ** {H12977} Each call to [sqlite3_update_hook(D,F,P)] overrides prior calls
  4812. ** to the same interface on the same [database connection] D.
  4813. **
  4814. ** {H12979} The update hook callback is not invoked when internal system
  4815. ** tables such as sqlite_master and sqlite_sequence are modified.
  4816. **
  4817. ** {H12981} The second parameter to the update callback
  4818. ** is one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE],
  4819. ** depending on the operation that caused the callback to be invoked.
  4820. **
  4821. ** {H12983} The third and fourth arguments to the callback contain pointers
  4822. ** to zero-terminated UTF-8 strings which are the names of the
  4823. ** database and table that is being updated.
  4824. ** {H12985} The final callback parameter is the rowid of the row after
  4825. ** the change occurs.
  4826. */
  4827. void *sqlite3_update_hook(
  4828. sqlite3*,
  4829. void(*)(void *,int ,char const *,char const *,sqlite3_int64),
  4830. void*
  4831. );
  4832. /*
  4833. ** CAPI3REF: Enable Or Disable Shared Pager Cache {H10330} <S30900>
  4834. ** KEYWORDS: {shared cache} {shared cache mode}
  4835. **
  4836. ** This routine enables or disables the sharing of the database cache
  4837. ** and schema data structures between [database connection | connections]
  4838. ** to the same database. Sharing is enabled if the argument is true
  4839. ** and disabled if the argument is false.
  4840. **
  4841. ** Cache sharing is enabled and disabled for an entire process. {END}
  4842. ** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
  4843. ** sharing was enabled or disabled for each thread separately.
  4844. **
  4845. ** The cache sharing mode set by this interface effects all subsequent
  4846. ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
  4847. ** Existing database connections continue use the sharing mode
  4848. ** that was in effect at the time they were opened.
  4849. **
  4850. ** Virtual tables cannot be used with a shared cache. When shared
  4851. ** cache is enabled, the [sqlite3_create_module()] API used to register
  4852. ** virtual tables will always return an error.
  4853. **
  4854. ** This routine returns [SQLITE_OK] if shared cache was enabled or disabled
  4855. ** successfully. An [error code] is returned otherwise.
  4856. **
  4857. ** Shared cache is disabled by default. But this might change in
  4858. ** future releases of SQLite. Applications that care about shared
  4859. ** cache setting should set it explicitly.
  4860. **
  4861. ** INVARIANTS:
  4862. **
  4863. ** {H10331} A successful invocation of [sqlite3_enable_shared_cache(B)]
  4864. ** will enable or disable shared cache mode for any subsequently
  4865. ** created [database connection] in the same process.
  4866. **
  4867. ** {H10336} When shared cache is enabled, the [sqlite3_create_module()]
  4868. ** interface will always return an error.
  4869. **
  4870. ** {H10337} The [sqlite3_enable_shared_cache(B)] interface returns
  4871. ** [SQLITE_OK] if shared cache was enabled or disabled successfully.
  4872. **
  4873. ** {H10339} Shared cache is disabled by default.
  4874. */
  4875. int sqlite3_enable_shared_cache(int);
  4876. /*
  4877. ** CAPI3REF: Attempt To Free Heap Memory {H17340} <S30220>
  4878. **
  4879. ** The sqlite3_release_memory() interface attempts to free N bytes
  4880. ** of heap memory by deallocating non-essential memory allocations
  4881. ** held by the database library. {END} Memory used to cache database
  4882. ** pages to improve performance is an example of non-essential memory.
  4883. ** sqlite3_release_memory() returns the number of bytes actually freed,
  4884. ** which might be more or less than the amount requested.
  4885. **
  4886. ** INVARIANTS:
  4887. **
  4888. ** {H17341} The [sqlite3_release_memory(N)] interface attempts to
  4889. ** free N bytes of heap memory by deallocating non-essential
  4890. ** memory allocations held by the database library.
  4891. **
  4892. ** {H16342} The [sqlite3_release_memory(N)] returns the number
  4893. ** of bytes actually freed, which might be more or less
  4894. ** than the amount requested.
  4895. */
  4896. int sqlite3_release_memory(int);
  4897. /*
  4898. ** CAPI3REF: Impose A Limit On Heap Size {H17350} <S30220>
  4899. **
  4900. ** The sqlite3_soft_heap_limit() interface places a "soft" limit
  4901. ** on the amount of heap memory that may be allocated by SQLite.
  4902. ** If an internal allocation is requested that would exceed the
  4903. ** soft heap limit, [sqlite3_release_memory()] is invoked one or
  4904. ** more times to free up some space before the allocation is performed.
  4905. **
  4906. ** The limit is called "soft", because if [sqlite3_release_memory()]
  4907. ** cannot free sufficient memory to prevent the limit from being exceeded,
  4908. ** the memory is allocated anyway and the current operation proceeds.
  4909. **
  4910. ** A negative or zero value for N means that there is no soft heap limit and
  4911. ** [sqlite3_release_memory()] will only be called when memory is exhausted.
  4912. ** The default value for the soft heap limit is zero.
  4913. **
  4914. ** SQLite makes a best effort to honor the soft heap limit.
  4915. ** But if the soft heap limit cannot be honored, execution will
  4916. ** continue without error or notification. This is why the limit is
  4917. ** called a "soft" limit. It is advisory only.
  4918. **
  4919. ** Prior to SQLite version 3.5.0, this routine only constrained the memory
  4920. ** allocated by a single thread - the same thread in which this routine
  4921. ** runs. Beginning with SQLite version 3.5.0, the soft heap limit is
  4922. ** applied to all threads. The value specified for the soft heap limit
  4923. ** is an upper bound on the total memory allocation for all threads. In
  4924. ** version 3.5.0 there is no mechanism for limiting the heap usage for
  4925. ** individual threads.
  4926. **
  4927. ** INVARIANTS:
  4928. **
  4929. ** {H16351} The [sqlite3_soft_heap_limit(N)] interface places a soft limit
  4930. ** of N bytes on the amount of heap memory that may be allocated
  4931. ** using [sqlite3_malloc()] or [sqlite3_realloc()] at any point
  4932. ** in time.
  4933. **
  4934. ** {H16352} If a call to [sqlite3_malloc()] or [sqlite3_realloc()] would
  4935. ** cause the total amount of allocated memory to exceed the
  4936. ** soft heap limit, then [sqlite3_release_memory()] is invoked
  4937. ** in an attempt to reduce the memory usage prior to proceeding
  4938. ** with the memory allocation attempt.
  4939. **
  4940. ** {H16353} Calls to [sqlite3_malloc()] or [sqlite3_realloc()] that trigger
  4941. ** attempts to reduce memory usage through the soft heap limit
  4942. ** mechanism continue even if the attempt to reduce memory
  4943. ** usage is unsuccessful.
  4944. **
  4945. ** {H16354} A negative or zero value for N in a call to
  4946. ** [sqlite3_soft_heap_limit(N)] means that there is no soft
  4947. ** heap limit and [sqlite3_release_memory()] will only be
  4948. ** called when memory is completely exhausted.
  4949. **
  4950. ** {H16355} The default value for the soft heap limit is zero.
  4951. **
  4952. ** {H16358} Each call to [sqlite3_soft_heap_limit(N)] overrides the
  4953. ** values set by all prior calls.
  4954. */
  4955. void sqlite3_soft_heap_limit(int);
  4956. /*
  4957. ** CAPI3REF: Extract Metadata About A Column Of A Table {H12850} <S60300>
  4958. **
  4959. ** This routine returns metadata about a specific column of a specific
  4960. ** database table accessible using the [database connection] handle
  4961. ** passed as the first function argument.
  4962. **
  4963. ** The column is identified by the second, third and fourth parameters to
  4964. ** this function. The second parameter is either the name of the database
  4965. ** (i.e. "main", "temp" or an attached database) containing the specified
  4966. ** table or NULL. If it is NULL, then all attached databases are searched
  4967. ** for the table using the same algorithm used by the database engine to
  4968. ** resolve unqualified table references.
  4969. **
  4970. ** The third and fourth parameters to this function are the table and column
  4971. ** name of the desired column, respectively. Neither of these parameters
  4972. ** may be NULL.
  4973. **
  4974. ** Metadata is returned by writing to the memory locations passed as the 5th
  4975. ** and subsequent parameters to this function. Any of these arguments may be
  4976. ** NULL, in which case the corresponding element of metadata is omitted.
  4977. **
  4978. ** <blockquote>
  4979. ** <table border="1">
  4980. ** <tr><th> Parameter <th> Output<br>Type <th> Description
  4981. **
  4982. ** <tr><td> 5th <td> const char* <td> Data type
  4983. ** <tr><td> 6th <td> const char* <td> Name of default collation sequence
  4984. ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
  4985. ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
  4986. ** <tr><td> 9th <td> int <td> True if column is AUTOINCREMENT
  4987. ** </table>
  4988. ** </blockquote>
  4989. **
  4990. ** The memory pointed to by the character pointers returned for the
  4991. ** declaration type and collation sequence is valid only until the next
  4992. ** call to any SQLite API function.
  4993. **
  4994. ** If the specified table is actually a view, an [error code] is returned.
  4995. **
  4996. ** If the specified column is "rowid", "oid" or "_rowid_" and an
  4997. ** INTEGER PRIMARY KEY column has been explicitly declared, then the output
  4998. ** parameters are set for the explicitly declared column. If there is no
  4999. ** explicitly declared INTEGER PRIMARY KEY column, then the output
  5000. ** parameters are set as follows:
  5001. **
  5002. ** <pre>
  5003. ** data type: "INTEGER"
  5004. ** collation sequence: "BINARY"
  5005. ** not null: 0
  5006. ** primary key: 1
  5007. ** auto increment: 0
  5008. ** </pre>
  5009. **
  5010. ** This function may load one or more schemas from database files. If an
  5011. ** error occurs during this process, or if the requested table or column
  5012. ** cannot be found, an [error code] is returned and an error message left
  5013. ** in the [database connection] (to be retrieved using sqlite3_errmsg()).
  5014. **
  5015. ** This API is only available if the library was compiled with the
  5016. ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
  5017. */
  5018. int sqlite3_table_column_metadata(
  5019. sqlite3 *db, /* Connection handle */
  5020. const char *zDbName, /* Database name or NULL */
  5021. const char *zTableName, /* Table name */
  5022. const char *zColumnName, /* Column name */
  5023. char const **pzDataType, /* OUTPUT: Declared data type */
  5024. char const **pzCollSeq, /* OUTPUT: Collation sequence name */
  5025. int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
  5026. int *pPrimaryKey, /* OUTPUT: True if column part of PK */
  5027. int *pAutoinc /* OUTPUT: True if column is auto-increment */
  5028. );
  5029. /*
  5030. ** CAPI3REF: Load An Extension {H12600} <S20500>
  5031. **
  5032. ** This interface loads an SQLite extension library from the named file.
  5033. **
  5034. ** {H12601} The sqlite3_load_extension() interface attempts to load an
  5035. ** SQLite extension library contained in the file zFile.
  5036. **
  5037. ** {H12602} The entry point is zProc.
  5038. **
  5039. ** {H12603} zProc may be 0, in which case the name of the entry point
  5040. ** defaults to "sqlite3_extension_init".
  5041. **
  5042. ** {H12604} The sqlite3_load_extension() interface shall return
  5043. ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
  5044. **
  5045. ** {H12605} If an error occurs and pzErrMsg is not 0, then the
  5046. ** [sqlite3_load_extension()] interface shall attempt to
  5047. ** fill *pzErrMsg with error message text stored in memory
  5048. ** obtained from [sqlite3_malloc()]. {END} The calling function
  5049. ** should free this memory by calling [sqlite3_free()].
  5050. **
  5051. ** {H12606} Extension loading must be enabled using
  5052. ** [sqlite3_enable_load_extension()] prior to calling this API,
  5053. ** otherwise an error will be returned.
  5054. */
  5055. int sqlite3_load_extension(
  5056. sqlite3 *db, /* Load the extension into this database connection */
  5057. const char *zFile, /* Name of the shared library containing extension */
  5058. const char *zProc, /* Entry point. Derived from zFile if 0 */
  5059. char **pzErrMsg /* Put error message here if not 0 */
  5060. );
  5061. /*
  5062. ** CAPI3REF: Enable Or Disable Extension Loading {H12620} <S20500>
  5063. **
  5064. ** So as not to open security holes in older applications that are
  5065. ** unprepared to deal with extension loading, and as a means of disabling
  5066. ** extension loading while evaluating user-entered SQL, the following API
  5067. ** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
  5068. **
  5069. ** Extension loading is off by default. See ticket #1863.
  5070. **
  5071. ** {H12621} Call the sqlite3_enable_load_extension() routine with onoff==1
  5072. ** to turn extension loading on and call it with onoff==0 to turn
  5073. ** it back off again.
  5074. **
  5075. ** {H12622} Extension loading is off by default.
  5076. */
  5077. int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
  5078. /*
  5079. ** CAPI3REF: Automatically Load An Extensions {H12640} <S20500>
  5080. **
  5081. ** This API can be invoked at program startup in order to register
  5082. ** one or more statically linked extensions that will be available
  5083. ** to all new [database connections]. {END}
  5084. **
  5085. ** This routine stores a pointer to the extension in an array that is
  5086. ** obtained from [sqlite3_malloc()]. If you run a memory leak checker
  5087. ** on your program and it reports a leak because of this array, invoke
  5088. ** [sqlite3_reset_auto_extension()] prior to shutdown to free the memory.
  5089. **
  5090. ** {H12641} This function registers an extension entry point that is
  5091. ** automatically invoked whenever a new [database connection]
  5092. ** is opened using [sqlite3_open()], [sqlite3_open16()],
  5093. ** or [sqlite3_open_v2()].
  5094. **
  5095. ** {H12642} Duplicate extensions are detected so calling this routine
  5096. ** multiple times with the same extension is harmless.
  5097. **
  5098. ** {H12643} This routine stores a pointer to the extension in an array
  5099. ** that is obtained from [sqlite3_malloc()].
  5100. **
  5101. ** {H12644} Automatic extensions apply across all threads.
  5102. */
  5103. int sqlite3_auto_extension(void *xEntryPoint);
  5104. /*
  5105. ** CAPI3REF: Reset Automatic Extension Loading {H12660} <S20500>
  5106. **
  5107. ** This function disables all previously registered automatic
  5108. ** extensions. {END} It undoes the effect of all prior
  5109. ** [sqlite3_auto_extension()] calls.
  5110. **
  5111. ** {H12661} This function disables all previously registered
  5112. ** automatic extensions.
  5113. **
  5114. ** {H12662} This function disables automatic extensions in all threads.
  5115. */
  5116. void sqlite3_reset_auto_extension(void);
  5117. /*
  5118. ****** EXPERIMENTAL - subject to change without notice **************
  5119. **
  5120. ** The interface to the virtual-table mechanism is currently considered
  5121. ** to be experimental. The interface might change in incompatible ways.
  5122. ** If this is a problem for you, do not use the interface at this time.
  5123. **
  5124. ** When the virtual-table mechanism stabilizes, we will declare the
  5125. ** interface fixed, support it indefinitely, and remove this comment.
  5126. */
  5127. /*
  5128. ** Structures used by the virtual table interface
  5129. */
  5130. typedef struct sqlite3_vtab sqlite3_vtab;
  5131. typedef struct sqlite3_index_info sqlite3_index_info;
  5132. typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
  5133. typedef struct sqlite3_module sqlite3_module;
  5134. /*
  5135. ** CAPI3REF: Virtual Table Object {H18000} <S20400>
  5136. ** KEYWORDS: sqlite3_module
  5137. ** EXPERIMENTAL
  5138. **
  5139. ** A module is a class of virtual tables. Each module is defined
  5140. ** by an instance of the following structure. This structure consists
  5141. ** mostly of methods for the module.
  5142. **
  5143. ** This interface is experimental and is subject to change or
  5144. ** removal in future releases of SQLite.
  5145. */
  5146. struct sqlite3_module {
  5147. int iVersion;
  5148. int (*xCreate)(sqlite3*, void *pAux,
  5149. int argc, const char *const*argv,
  5150. sqlite3_vtab **ppVTab, char**);
  5151. int (*xConnect)(sqlite3*, void *pAux,
  5152. int argc, const char *const*argv,
  5153. sqlite3_vtab **ppVTab, char**);
  5154. int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
  5155. int (*xDisconnect)(sqlite3_vtab *pVTab);
  5156. int (*xDestroy)(sqlite3_vtab *pVTab);
  5157. int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
  5158. int (*xClose)(sqlite3_vtab_cursor*);
  5159. int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
  5160. int argc, sqlite3_value **argv);
  5161. int (*xNext)(sqlite3_vtab_cursor*);
  5162. int (*xEof)(sqlite3_vtab_cursor*);
  5163. int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
  5164. int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
  5165. int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
  5166. int (*xBegin)(sqlite3_vtab *pVTab);
  5167. int (*xSync)(sqlite3_vtab *pVTab);
  5168. int (*xCommit)(sqlite3_vtab *pVTab);
  5169. int (*xRollback)(sqlite3_vtab *pVTab);
  5170. int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
  5171. void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
  5172. void **ppArg);
  5173. int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
  5174. };
  5175. /*
  5176. ** CAPI3REF: Virtual Table Indexing Information {H18100} <S20400>
  5177. ** KEYWORDS: sqlite3_index_info
  5178. ** EXPERIMENTAL
  5179. **
  5180. ** The sqlite3_index_info structure and its substructures is used to
  5181. ** pass information into and receive the reply from the xBestIndex
  5182. ** method of an sqlite3_module. The fields under **Inputs** are the
  5183. ** inputs to xBestIndex and are read-only. xBestIndex inserts its
  5184. ** results into the **Outputs** fields.
  5185. **
  5186. ** The aConstraint[] array records WHERE clause constraints of the form:
  5187. **
  5188. ** <pre>column OP expr</pre>
  5189. **
  5190. ** where OP is =, &lt;, &lt;=, &gt;, or &gt;=. The particular operator is
  5191. ** stored in aConstraint[].op. The index of the column is stored in
  5192. ** aConstraint[].iColumn. aConstraint[].usable is TRUE if the
  5193. ** expr on the right-hand side can be evaluated (and thus the constraint
  5194. ** is usable) and false if it cannot.
  5195. **
  5196. ** The optimizer automatically inverts terms of the form "expr OP column"
  5197. ** and makes other simplifications to the WHERE clause in an attempt to
  5198. ** get as many WHERE clause terms into the form shown above as possible.
  5199. ** The aConstraint[] array only reports WHERE clause terms in the correct
  5200. ** form that refer to the particular virtual table being queried.
  5201. **
  5202. ** Information about the ORDER BY clause is stored in aOrderBy[].
  5203. ** Each term of aOrderBy records a column of the ORDER BY clause.
  5204. **
  5205. ** The xBestIndex method must fill aConstraintUsage[] with information
  5206. ** about what parameters to pass to xFilter. If argvIndex>0 then
  5207. ** the right-hand side of the corresponding aConstraint[] is evaluated
  5208. ** and becomes the argvIndex-th entry in argv. If aConstraintUsage[].omit
  5209. ** is true, then the constraint is assumed to be fully handled by the
  5210. ** virtual table and is not checked again by SQLite.
  5211. **
  5212. ** The idxNum and idxPtr values are recorded and passed into xFilter.
  5213. ** sqlite3_free() is used to free idxPtr if needToFreeIdxPtr is true.
  5214. **
  5215. ** The orderByConsumed means that output from xFilter will occur in
  5216. ** the correct order to satisfy the ORDER BY clause so that no separate
  5217. ** sorting step is required.
  5218. **
  5219. ** The estimatedCost value is an estimate of the cost of doing the
  5220. ** particular lookup. A full scan of a table with N entries should have
  5221. ** a cost of N. A binary search of a table of N entries should have a
  5222. ** cost of approximately log(N).
  5223. **
  5224. ** This interface is experimental and is subject to change or
  5225. ** removal in future releases of SQLite.
  5226. */
  5227. struct sqlite3_index_info {
  5228. /* Inputs */
  5229. int nConstraint; /* Number of entries in aConstraint */
  5230. struct sqlite3_index_constraint {
  5231. int iColumn; /* Column on left-hand side of constraint */
  5232. unsigned char op; /* Constraint operator */
  5233. unsigned char usable; /* True if this constraint is usable */
  5234. int iTermOffset; /* Used internally - xBestIndex should ignore */
  5235. } *aConstraint; /* Table of WHERE clause constraints */
  5236. int nOrderBy; /* Number of terms in the ORDER BY clause */
  5237. struct sqlite3_index_orderby {
  5238. int iColumn; /* Column number */
  5239. unsigned char desc; /* True for DESC. False for ASC. */
  5240. } *aOrderBy; /* The ORDER BY clause */
  5241. /* Outputs */
  5242. struct sqlite3_index_constraint_usage {
  5243. int argvIndex; /* if >0, constraint is part of argv to xFilter */
  5244. unsigned char omit; /* Do not code a test for this constraint */
  5245. } *aConstraintUsage;
  5246. int idxNum; /* Number used to identify the index */
  5247. char *idxStr; /* String, possibly obtained from sqlite3_malloc */
  5248. int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
  5249. int orderByConsumed; /* True if output is already ordered */
  5250. double estimatedCost; /* Estimated cost of using this index */
  5251. };
  5252. #define SQLITE_INDEX_CONSTRAINT_EQ 2
  5253. #define SQLITE_INDEX_CONSTRAINT_GT 4
  5254. #define SQLITE_INDEX_CONSTRAINT_LE 8
  5255. #define SQLITE_INDEX_CONSTRAINT_LT 16
  5256. #define SQLITE_INDEX_CONSTRAINT_GE 32
  5257. #define SQLITE_INDEX_CONSTRAINT_MATCH 64
  5258. /*
  5259. ** CAPI3REF: Register A Virtual Table Implementation {H18200} <S20400>
  5260. ** EXPERIMENTAL
  5261. **
  5262. ** This routine is used to register a new module name with a
  5263. ** [database connection]. Module names must be registered before
  5264. ** creating new virtual tables on the module, or before using
  5265. ** preexisting virtual tables of the module.
  5266. **
  5267. ** This interface is experimental and is subject to change or
  5268. ** removal in future releases of SQLite.
  5269. */
  5270. int sqlite3_create_module(
  5271. sqlite3 *db, /* SQLite connection to register module with */
  5272. const char *zName, /* Name of the module */
  5273. const sqlite3_module *, /* Methods for the module */
  5274. void * /* Client data for xCreate/xConnect */
  5275. );
  5276. /*
  5277. ** CAPI3REF: Register A Virtual Table Implementation {H18210} <S20400>
  5278. ** EXPERIMENTAL
  5279. **
  5280. ** This routine is identical to the [sqlite3_create_module()] method above,
  5281. ** except that it allows a destructor function to be specified. It is
  5282. ** even more experimental than the rest of the virtual tables API.
  5283. */
  5284. int sqlite3_create_module_v2(
  5285. sqlite3 *db, /* SQLite connection to register module with */
  5286. const char *zName, /* Name of the module */
  5287. const sqlite3_module *, /* Methods for the module */
  5288. void *, /* Client data for xCreate/xConnect */
  5289. void(*xDestroy)(void*) /* Module destructor function */
  5290. );
  5291. /*
  5292. ** CAPI3REF: Virtual Table Instance Object {H18010} <S20400>
  5293. ** KEYWORDS: sqlite3_vtab
  5294. ** EXPERIMENTAL
  5295. **
  5296. ** Every module implementation uses a subclass of the following structure
  5297. ** to describe a particular instance of the module. Each subclass will
  5298. ** be tailored to the specific needs of the module implementation.
  5299. ** The purpose of this superclass is to define certain fields that are
  5300. ** common to all module implementations.
  5301. **
  5302. ** Virtual tables methods can set an error message by assigning a
  5303. ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
  5304. ** take care that any prior string is freed by a call to [sqlite3_free()]
  5305. ** prior to assigning a new string to zErrMsg. After the error message
  5306. ** is delivered up to the client application, the string will be automatically
  5307. ** freed by sqlite3_free() and the zErrMsg field will be zeroed. Note
  5308. ** that sqlite3_mprintf() and sqlite3_free() are used on the zErrMsg field
  5309. ** since virtual tables are commonly implemented in loadable extensions which
  5310. ** do not have access to sqlite3MPrintf() or sqlite3Free().
  5311. **
  5312. ** This interface is experimental and is subject to change or
  5313. ** removal in future releases of SQLite.
  5314. */
  5315. struct sqlite3_vtab {
  5316. const sqlite3_module *pModule; /* The module for this virtual table */
  5317. int nRef; /* Used internally */
  5318. char *zErrMsg; /* Error message from sqlite3_mprintf() */
  5319. /* Virtual table implementations will typically add additional fields */
  5320. };
  5321. /*
  5322. ** CAPI3REF: Virtual Table Cursor Object {H18020} <S20400>
  5323. ** KEYWORDS: sqlite3_vtab_cursor
  5324. ** EXPERIMENTAL
  5325. **
  5326. ** Every module implementation uses a subclass of the following structure
  5327. ** to describe cursors that point into the virtual table and are used
  5328. ** to loop through the virtual table. Cursors are created using the
  5329. ** xOpen method of the module. Each module implementation will define
  5330. ** the content of a cursor structure to suit its own needs.
  5331. **
  5332. ** This superclass exists in order to define fields of the cursor that
  5333. ** are common to all implementations.
  5334. **
  5335. ** This interface is experimental and is subject to change or
  5336. ** removal in future releases of SQLite.
  5337. */
  5338. struct sqlite3_vtab_cursor {
  5339. sqlite3_vtab *pVtab; /* Virtual table of this cursor */
  5340. /* Virtual table implementations will typically add additional fields */
  5341. };
  5342. /*
  5343. ** CAPI3REF: Declare The Schema Of A Virtual Table {H18280} <S20400>
  5344. ** EXPERIMENTAL
  5345. **
  5346. ** The xCreate and xConnect methods of a module use the following API
  5347. ** to declare the format (the names and datatypes of the columns) of
  5348. ** the virtual tables they implement.
  5349. **
  5350. ** This interface is experimental and is subject to change or
  5351. ** removal in future releases of SQLite.
  5352. */
  5353. int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable);
  5354. /*
  5355. ** CAPI3REF: Overload A Function For A Virtual Table {H18300} <S20400>
  5356. ** EXPERIMENTAL
  5357. **
  5358. ** Virtual tables can provide alternative implementations of functions
  5359. ** using the xFindFunction method. But global versions of those functions
  5360. ** must exist in order to be overloaded.
  5361. **
  5362. ** This API makes sure a global version of a function with a particular
  5363. ** name and number of parameters exists. If no such function exists
  5364. ** before this API is called, a new function is created. The implementation
  5365. ** of the new function always causes an exception to be thrown. So
  5366. ** the new function is not good for anything by itself. Its only
  5367. ** purpose is to be a placeholder function that can be overloaded
  5368. ** by virtual tables.
  5369. **
  5370. ** This API should be considered part of the virtual table interface,
  5371. ** which is experimental and subject to change.
  5372. */
  5373. int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
  5374. /*
  5375. ** The interface to the virtual-table mechanism defined above (back up
  5376. ** to a comment remarkably similar to this one) is currently considered
  5377. ** to be experimental. The interface might change in incompatible ways.
  5378. ** If this is a problem for you, do not use the interface at this time.
  5379. **
  5380. ** When the virtual-table mechanism stabilizes, we will declare the
  5381. ** interface fixed, support it indefinitely, and remove this comment.
  5382. **
  5383. ****** EXPERIMENTAL - subject to change without notice **************
  5384. */
  5385. /*
  5386. ** CAPI3REF: A Handle To An Open BLOB {H17800} <S30230>
  5387. ** KEYWORDS: {BLOB handle} {BLOB handles}
  5388. **
  5389. ** An instance of this object represents an open BLOB on which
  5390. ** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
  5391. ** Objects of this type are created by [sqlite3_blob_open()]
  5392. ** and destroyed by [sqlite3_blob_close()].
  5393. ** The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
  5394. ** can be used to read or write small subsections of the BLOB.
  5395. ** The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
  5396. */
  5397. typedef struct sqlite3_blob sqlite3_blob;
  5398. /*
  5399. ** CAPI3REF: Open A BLOB For Incremental I/O {H17810} <S30230>
  5400. **
  5401. ** This interfaces opens a [BLOB handle | handle] to the BLOB located
  5402. ** in row iRow, column zColumn, table zTable in database zDb;
  5403. ** in other words, the same BLOB that would be selected by:
  5404. **
  5405. ** <pre>
  5406. ** SELECT zColumn FROM zDb.zTable WHERE rowid = iRow;
  5407. ** </pre> {END}
  5408. **
  5409. ** If the flags parameter is non-zero, the the BLOB is opened for read
  5410. ** and write access. If it is zero, the BLOB is opened for read access.
  5411. **
  5412. ** Note that the database name is not the filename that contains
  5413. ** the database but rather the symbolic name of the database that
  5414. ** is assigned when the database is connected using [ATTACH].
  5415. ** For the main database file, the database name is "main".
  5416. ** For TEMP tables, the database name is "temp".
  5417. **
  5418. ** On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
  5419. ** to *ppBlob. Otherwise an [error code] is returned and any value written
  5420. ** to *ppBlob should not be used by the caller.
  5421. ** This function sets the [database connection] error code and message
  5422. ** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()].
  5423. **
  5424. ** If the row that a BLOB handle points to is modified by an
  5425. ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
  5426. ** then the BLOB handle is marked as "expired".
  5427. ** This is true if any column of the row is changed, even a column
  5428. ** other than the one the BLOB handle is open on.
  5429. ** Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
  5430. ** a expired BLOB handle fail with an return code of [SQLITE_ABORT].
  5431. ** Changes written into a BLOB prior to the BLOB expiring are not
  5432. ** rollback by the expiration of the BLOB. Such changes will eventually
  5433. ** commit if the transaction continues to completion.
  5434. **
  5435. ** INVARIANTS:
  5436. **
  5437. ** {H17813} A successful invocation of the [sqlite3_blob_open(D,B,T,C,R,F,P)]
  5438. ** interface shall open an [sqlite3_blob] object P on the BLOB
  5439. ** in column C of the table T in the database B on
  5440. ** the [database connection] D.
  5441. **
  5442. ** {H17814} A successful invocation of [sqlite3_blob_open(D,...)] shall start
  5443. ** a new transaction on the [database connection] D if that
  5444. ** connection is not already in a transaction.
  5445. **
  5446. ** {H17816} The [sqlite3_blob_open(D,B,T,C,R,F,P)] interface shall open
  5447. ** the BLOB for read and write access if and only if the F
  5448. ** parameter is non-zero.
  5449. **
  5450. ** {H17819} The [sqlite3_blob_open()] interface shall return [SQLITE_OK] on
  5451. ** success and an appropriate [error code] on failure.
  5452. **
  5453. ** {H17821} If an error occurs during evaluation of [sqlite3_blob_open(D,...)]
  5454. ** then subsequent calls to [sqlite3_errcode(D)],
  5455. ** [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return
  5456. ** information appropriate for that error.
  5457. **
  5458. ** {H17824} If any column in the row that a [sqlite3_blob] has open is
  5459. ** changed by a separate [UPDATE] or [DELETE] statement or by
  5460. ** an [ON CONFLICT] side effect, then the [sqlite3_blob] shall
  5461. ** be marked as invalid.
  5462. */
  5463. int sqlite3_blob_open(
  5464. sqlite3*,
  5465. const char *zDb,
  5466. const char *zTable,
  5467. const char *zColumn,
  5468. sqlite3_int64 iRow,
  5469. int flags,
  5470. sqlite3_blob **ppBlob
  5471. );
  5472. /*
  5473. ** CAPI3REF: Close A BLOB Handle {H17830} <S30230>
  5474. **
  5475. ** Closes an open [BLOB handle].
  5476. **
  5477. ** Closing a BLOB shall cause the current transaction to commit
  5478. ** if there are no other BLOBs, no pending prepared statements, and the
  5479. ** database connection is in [autocommit mode].
  5480. ** If any writes were made to the BLOB, they might be held in cache
  5481. ** until the close operation if they will fit. {END}
  5482. **
  5483. ** Closing the BLOB often forces the changes
  5484. ** out to disk and so if any I/O errors occur, they will likely occur
  5485. ** at the time when the BLOB is closed. {H17833} Any errors that occur during
  5486. ** closing are reported as a non-zero return value.
  5487. **
  5488. ** The BLOB is closed unconditionally. Even if this routine returns
  5489. ** an error code, the BLOB is still closed.
  5490. **
  5491. ** INVARIANTS:
  5492. **
  5493. ** {H17833} The [sqlite3_blob_close(P)] interface closes an [sqlite3_blob]
  5494. ** object P previously opened using [sqlite3_blob_open()].
  5495. **
  5496. ** {H17836} Closing an [sqlite3_blob] object using
  5497. ** [sqlite3_blob_close()] shall cause the current transaction to
  5498. ** commit if there are no other open [sqlite3_blob] objects
  5499. ** or [prepared statements] on the same [database connection] and
  5500. ** the database connection is in [autocommit mode].
  5501. **
  5502. ** {H17839} The [sqlite3_blob_close(P)] interfaces shall close the
  5503. ** [sqlite3_blob] object P unconditionally, even if
  5504. ** [sqlite3_blob_close(P)] returns something other than [SQLITE_OK].
  5505. */
  5506. int sqlite3_blob_close(sqlite3_blob *);
  5507. /*
  5508. ** CAPI3REF: Return The Size Of An Open BLOB {H17840} <S30230>
  5509. **
  5510. ** Returns the size in bytes of the BLOB accessible via the open
  5511. ** []BLOB handle] in its only argument.
  5512. **
  5513. ** INVARIANTS:
  5514. **
  5515. ** {H17843} The [sqlite3_blob_bytes(P)] interface returns the size
  5516. ** in bytes of the BLOB that the [sqlite3_blob] object P
  5517. ** refers to.
  5518. */
  5519. int sqlite3_blob_bytes(sqlite3_blob *);
  5520. /*
  5521. ** CAPI3REF: Read Data From A BLOB Incrementally {H17850} <S30230>
  5522. **
  5523. ** This function is used to read data from an open [BLOB handle] into a
  5524. ** caller-supplied buffer. N bytes of data are copied into buffer Z
  5525. ** from the open BLOB, starting at offset iOffset.
  5526. **
  5527. ** If offset iOffset is less than N bytes from the end of the BLOB,
  5528. ** [SQLITE_ERROR] is returned and no data is read. If N or iOffset is
  5529. ** less than zero, [SQLITE_ERROR] is returned and no data is read.
  5530. **
  5531. ** An attempt to read from an expired [BLOB handle] fails with an
  5532. ** error code of [SQLITE_ABORT].
  5533. **
  5534. ** On success, SQLITE_OK is returned.
  5535. ** Otherwise, an [error code] or an [extended error code] is returned.
  5536. **
  5537. ** INVARIANTS:
  5538. **
  5539. ** {H17853} A successful invocation of [sqlite3_blob_read(P,Z,N,X)]
  5540. ** shall reads N bytes of data out of the BLOB referenced by
  5541. ** [BLOB handle] P beginning at offset X and store those bytes
  5542. ** into buffer Z.
  5543. **
  5544. ** {H17856} In [sqlite3_blob_read(P,Z,N,X)] if the size of the BLOB
  5545. ** is less than N+X bytes, then the function shall leave the
  5546. ** Z buffer unchanged and return [SQLITE_ERROR].
  5547. **
  5548. ** {H17859} In [sqlite3_blob_read(P,Z,N,X)] if X or N is less than zero
  5549. ** then the function shall leave the Z buffer unchanged
  5550. ** and return [SQLITE_ERROR].
  5551. **
  5552. ** {H17862} The [sqlite3_blob_read(P,Z,N,X)] interface shall return [SQLITE_OK]
  5553. ** if N bytes are successfully read into buffer Z.
  5554. **
  5555. ** {H17863} If the [BLOB handle] P is expired and X and N are within bounds
  5556. ** then [sqlite3_blob_read(P,Z,N,X)] shall leave the Z buffer
  5557. ** unchanged and return [SQLITE_ABORT].
  5558. **
  5559. ** {H17865} If the requested read could not be completed,
  5560. ** the [sqlite3_blob_read(P,Z,N,X)] interface shall return an
  5561. ** appropriate [error code] or [extended error code].
  5562. **
  5563. ** {H17868} If an error occurs during evaluation of [sqlite3_blob_read(P,...)]
  5564. ** then subsequent calls to [sqlite3_errcode(D)],
  5565. ** [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return
  5566. ** information appropriate for that error, where D is the
  5567. ** [database connection] that was used to open the [BLOB handle] P.
  5568. */
  5569. int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
  5570. /*
  5571. ** CAPI3REF: Write Data Into A BLOB Incrementally {H17870} <S30230>
  5572. **
  5573. ** This function is used to write data into an open [BLOB handle] from a
  5574. ** caller-supplied buffer. N bytes of data are copied from the buffer Z
  5575. ** into the open BLOB, starting at offset iOffset.
  5576. **
  5577. ** If the [BLOB handle] passed as the first argument was not opened for
  5578. ** writing (the flags parameter to [sqlite3_blob_open()] was zero),
  5579. ** this function returns [SQLITE_READONLY].
  5580. **
  5581. ** This function may only modify the contents of the BLOB; it is
  5582. ** not possible to increase the size of a BLOB using this API.
  5583. ** If offset iOffset is less than N bytes from the end of the BLOB,
  5584. ** [SQLITE_ERROR] is returned and no data is written. If N is
  5585. ** less than zero [SQLITE_ERROR] is returned and no data is written.
  5586. **
  5587. ** An attempt to write to an expired [BLOB handle] fails with an
  5588. ** error code of [SQLITE_ABORT]. Writes to the BLOB that occurred
  5589. ** before the [BLOB handle] expired are not rolled back by the
  5590. ** expiration of the handle, though of course those changes might
  5591. ** have been overwritten by the statement that expired the BLOB handle
  5592. ** or by other independent statements.
  5593. **
  5594. ** On success, SQLITE_OK is returned.
  5595. ** Otherwise, an [error code] or an [extended error code] is returned.
  5596. **
  5597. ** INVARIANTS:
  5598. **
  5599. ** {H17873} A successful invocation of [sqlite3_blob_write(P,Z,N,X)]
  5600. ** shall write N bytes of data from buffer Z into the BLOB
  5601. ** referenced by [BLOB handle] P beginning at offset X into
  5602. ** the BLOB.
  5603. **
  5604. ** {H17874} In the absence of other overridding changes, the changes
  5605. ** written to a BLOB by [sqlite3_blob_write()] shall
  5606. ** remain in effect after the associated [BLOB handle] expires.
  5607. **
  5608. ** {H17875} If the [BLOB handle] P was opened for reading only then
  5609. ** an invocation of [sqlite3_blob_write(P,Z,N,X)] shall leave
  5610. ** the referenced BLOB unchanged and return [SQLITE_READONLY].
  5611. **
  5612. ** {H17876} If the size of the BLOB referenced by [BLOB handle] P is
  5613. ** less than N+X bytes then [sqlite3_blob_write(P,Z,N,X)] shall
  5614. ** leave the BLOB unchanged and return [SQLITE_ERROR].
  5615. **
  5616. ** {H17877} If the [BLOB handle] P is expired and X and N are within bounds
  5617. ** then [sqlite3_blob_read(P,Z,N,X)] shall leave the BLOB
  5618. ** unchanged and return [SQLITE_ABORT].
  5619. **
  5620. ** {H17879} If X or N are less than zero then [sqlite3_blob_write(P,Z,N,X)]
  5621. ** shall leave the BLOB referenced by [BLOB handle] P unchanged
  5622. ** and return [SQLITE_ERROR].
  5623. **
  5624. ** {H17882} The [sqlite3_blob_write(P,Z,N,X)] interface shall return
  5625. ** [SQLITE_OK] if N bytes where successfully written into the BLOB.
  5626. **
  5627. ** {H17885} If the requested write could not be completed,
  5628. ** the [sqlite3_blob_write(P,Z,N,X)] interface shall return an
  5629. ** appropriate [error code] or [extended error code].
  5630. **
  5631. ** {H17888} If an error occurs during evaluation of [sqlite3_blob_write(D,...)]
  5632. ** then subsequent calls to [sqlite3_errcode(D)],
  5633. ** [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return
  5634. ** information appropriate for that error.
  5635. */
  5636. int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
  5637. /*
  5638. ** CAPI3REF: Virtual File System Objects {H11200} <S20100>
  5639. **
  5640. ** A virtual filesystem (VFS) is an [sqlite3_vfs] object
  5641. ** that SQLite uses to interact
  5642. ** with the underlying operating system. Most SQLite builds come with a
  5643. ** single default VFS that is appropriate for the host computer.
  5644. ** New VFSes can be registered and existing VFSes can be unregistered.
  5645. ** The following interfaces are provided.
  5646. **
  5647. ** The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
  5648. ** Names are case sensitive.
  5649. ** Names are zero-terminated UTF-8 strings.
  5650. ** If there is no match, a NULL pointer is returned.
  5651. ** If zVfsName is NULL then the default VFS is returned.
  5652. **
  5653. ** New VFSes are registered with sqlite3_vfs_register().
  5654. ** Each new VFS becomes the default VFS if the makeDflt flag is set.
  5655. ** The same VFS can be registered multiple times without injury.
  5656. ** To make an existing VFS into the default VFS, register it again
  5657. ** with the makeDflt flag set. If two different VFSes with the
  5658. ** same name are registered, the behavior is undefined. If a
  5659. ** VFS is registered with a name that is NULL or an empty string,
  5660. ** then the behavior is undefined.
  5661. **
  5662. ** Unregister a VFS with the sqlite3_vfs_unregister() interface.
  5663. ** If the default VFS is unregistered, another VFS is chosen as
  5664. ** the default. The choice for the new VFS is arbitrary.
  5665. **
  5666. ** INVARIANTS:
  5667. **
  5668. ** {H11203} The [sqlite3_vfs_find(N)] interface returns a pointer to the
  5669. ** registered [sqlite3_vfs] object whose name exactly matches
  5670. ** the zero-terminated UTF-8 string N, or it returns NULL if
  5671. ** there is no match.
  5672. **
  5673. ** {H11206} If the N parameter to [sqlite3_vfs_find(N)] is NULL then
  5674. ** the function returns a pointer to the default [sqlite3_vfs]
  5675. ** object if there is one, or NULL if there is no default
  5676. ** [sqlite3_vfs] object.
  5677. **
  5678. ** {H11209} The [sqlite3_vfs_register(P,F)] interface registers the
  5679. ** well-formed [sqlite3_vfs] object P using the name given
  5680. ** by the zName field of the object.
  5681. **
  5682. ** {H11212} Using the [sqlite3_vfs_register(P,F)] interface to register
  5683. ** the same [sqlite3_vfs] object multiple times is a harmless no-op.
  5684. **
  5685. ** {H11215} The [sqlite3_vfs_register(P,F)] interface makes the [sqlite3_vfs]
  5686. ** object P the default [sqlite3_vfs] object if F is non-zero.
  5687. **
  5688. ** {H11218} The [sqlite3_vfs_unregister(P)] interface unregisters the
  5689. ** [sqlite3_vfs] object P so that it is no longer returned by
  5690. ** subsequent calls to [sqlite3_vfs_find()].
  5691. */
  5692. sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
  5693. int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
  5694. int sqlite3_vfs_unregister(sqlite3_vfs*);
  5695. /*
  5696. ** CAPI3REF: Mutexes {H17000} <S20000>
  5697. **
  5698. ** The SQLite core uses these routines for thread
  5699. ** synchronization. Though they are intended for internal
  5700. ** use by SQLite, code that links against SQLite is
  5701. ** permitted to use any of these routines.
  5702. **
  5703. ** The SQLite source code contains multiple implementations
  5704. ** of these mutex routines. An appropriate implementation
  5705. ** is selected automatically at compile-time. The following
  5706. ** implementations are available in the SQLite core:
  5707. **
  5708. ** <ul>
  5709. ** <li> SQLITE_MUTEX_OS2
  5710. ** <li> SQLITE_MUTEX_PTHREAD
  5711. ** <li> SQLITE_MUTEX_W32
  5712. ** <li> SQLITE_MUTEX_NOOP
  5713. ** </ul>
  5714. **
  5715. ** The SQLITE_MUTEX_NOOP implementation is a set of routines
  5716. ** that does no real locking and is appropriate for use in
  5717. ** a single-threaded application. The SQLITE_MUTEX_OS2,
  5718. ** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations
  5719. ** are appropriate for use on OS/2, Unix, and Windows.
  5720. **
  5721. ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
  5722. ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
  5723. ** implementation is included with the library. In this case the
  5724. ** application must supply a custom mutex implementation using the
  5725. ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
  5726. ** before calling sqlite3_initialize() or any other public sqlite3_
  5727. ** function that calls sqlite3_initialize().
  5728. **
  5729. ** {H17011} The sqlite3_mutex_alloc() routine allocates a new
  5730. ** mutex and returns a pointer to it. {H17012} If it returns NULL
  5731. ** that means that a mutex could not be allocated. {H17013} SQLite
  5732. ** will unwind its stack and return an error. {H17014} The argument
  5733. ** to sqlite3_mutex_alloc() is one of these integer constants:
  5734. **
  5735. ** <ul>
  5736. ** <li> SQLITE_MUTEX_FAST
  5737. ** <li> SQLITE_MUTEX_RECURSIVE
  5738. ** <li> SQLITE_MUTEX_STATIC_MASTER
  5739. ** <li> SQLITE_MUTEX_STATIC_MEM
  5740. ** <li> SQLITE_MUTEX_STATIC_MEM2
  5741. ** <li> SQLITE_MUTEX_STATIC_PRNG
  5742. ** <li> SQLITE_MUTEX_STATIC_LRU
  5743. ** <li> SQLITE_MUTEX_STATIC_LRU2
  5744. ** </ul>
  5745. **
  5746. ** {H17015} The first two constants cause sqlite3_mutex_alloc() to create
  5747. ** a new mutex. The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
  5748. ** is used but not necessarily so when SQLITE_MUTEX_FAST is used. {END}
  5749. ** The mutex implementation does not need to make a distinction
  5750. ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
  5751. ** not want to. {H17016} But SQLite will only request a recursive mutex in
  5752. ** cases where it really needs one. {END} If a faster non-recursive mutex
  5753. ** implementation is available on the host platform, the mutex subsystem
  5754. ** might return such a mutex in response to SQLITE_MUTEX_FAST.
  5755. **
  5756. ** {H17017} The other allowed parameters to sqlite3_mutex_alloc() each return
  5757. ** a pointer to a static preexisting mutex. {END} Four static mutexes are
  5758. ** used by the current version of SQLite. Future versions of SQLite
  5759. ** may add additional static mutexes. Static mutexes are for internal
  5760. ** use by SQLite only. Applications that use SQLite mutexes should
  5761. ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
  5762. ** SQLITE_MUTEX_RECURSIVE.
  5763. **
  5764. ** {H17018} Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
  5765. ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
  5766. ** returns a different mutex on every call. {H17034} But for the static
  5767. ** mutex types, the same mutex is returned on every call that has
  5768. ** the same type number.
  5769. **
  5770. ** {H17019} The sqlite3_mutex_free() routine deallocates a previously
  5771. ** allocated dynamic mutex. {H17020} SQLite is careful to deallocate every
  5772. ** dynamic mutex that it allocates. {A17021} The dynamic mutexes must not be in
  5773. ** use when they are deallocated. {A17022} Attempting to deallocate a static
  5774. ** mutex results in undefined behavior. {H17023} SQLite never deallocates
  5775. ** a static mutex. {END}
  5776. **
  5777. ** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
  5778. ** to enter a mutex. {H17024} If another thread is already within the mutex,
  5779. ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
  5780. ** SQLITE_BUSY. {H17025} The sqlite3_mutex_try() interface returns [SQLITE_OK]
  5781. ** upon successful entry. {H17026} Mutexes created using
  5782. ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
  5783. ** {H17027} In such cases the,
  5784. ** mutex must be exited an equal number of times before another thread
  5785. ** can enter. {A17028} If the same thread tries to enter any other
  5786. ** kind of mutex more than once, the behavior is undefined.
  5787. ** {H17029} SQLite will never exhibit
  5788. ** such behavior in its own use of mutexes.
  5789. **
  5790. ** Some systems (for example, Windows 95) do not support the operation
  5791. ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
  5792. ** will always return SQLITE_BUSY. {H17030} The SQLite core only ever uses
  5793. ** sqlite3_mutex_try() as an optimization so this is acceptable behavior.
  5794. **
  5795. ** {H17031} The sqlite3_mutex_leave() routine exits a mutex that was
  5796. ** previously entered by the same thread. {A17032} The behavior
  5797. ** is undefined if the mutex is not currently entered by the
  5798. ** calling thread or is not currently allocated. {H17033} SQLite will
  5799. ** never do either. {END}
  5800. **
  5801. ** If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
  5802. ** sqlite3_mutex_leave() is a NULL pointer, then all three routines
  5803. ** behave as no-ops.
  5804. **
  5805. ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
  5806. */
  5807. sqlite3_mutex *sqlite3_mutex_alloc(int);
  5808. void sqlite3_mutex_free(sqlite3_mutex*);
  5809. void sqlite3_mutex_enter(sqlite3_mutex*);
  5810. int sqlite3_mutex_try(sqlite3_mutex*);
  5811. void sqlite3_mutex_leave(sqlite3_mutex*);
  5812. /*
  5813. ** CAPI3REF: Mutex Methods Object {H17120} <S20130>
  5814. ** EXPERIMENTAL
  5815. **
  5816. ** An instance of this structure defines the low-level routines
  5817. ** used to allocate and use mutexes.
  5818. **
  5819. ** Usually, the default mutex implementations provided by SQLite are
  5820. ** sufficient, however the user has the option of substituting a custom
  5821. ** implementation for specialized deployments or systems for which SQLite
  5822. ** does not provide a suitable implementation. In this case, the user
  5823. ** creates and populates an instance of this structure to pass
  5824. ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
  5825. ** Additionally, an instance of this structure can be used as an
  5826. ** output variable when querying the system for the current mutex
  5827. ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
  5828. **
  5829. ** The xMutexInit method defined by this structure is invoked as
  5830. ** part of system initialization by the sqlite3_initialize() function.
  5831. ** {H17001} The xMutexInit routine shall be called by SQLite once for each
  5832. ** effective call to [sqlite3_initialize()].
  5833. **
  5834. ** The xMutexEnd method defined by this structure is invoked as
  5835. ** part of system shutdown by the sqlite3_shutdown() function. The
  5836. ** implementation of this method is expected to release all outstanding
  5837. ** resources obtained by the mutex methods implementation, especially
  5838. ** those obtained by the xMutexInit method. {H17003} The xMutexEnd()
  5839. ** interface shall be invoked once for each call to [sqlite3_shutdown()].
  5840. **
  5841. ** The remaining seven methods defined by this structure (xMutexAlloc,
  5842. ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
  5843. ** xMutexNotheld) implement the following interfaces (respectively):
  5844. **
  5845. ** <ul>
  5846. ** <li> [sqlite3_mutex_alloc()] </li>
  5847. ** <li> [sqlite3_mutex_free()] </li>
  5848. ** <li> [sqlite3_mutex_enter()] </li>
  5849. ** <li> [sqlite3_mutex_try()] </li>
  5850. ** <li> [sqlite3_mutex_leave()] </li>
  5851. ** <li> [sqlite3_mutex_held()] </li>
  5852. ** <li> [sqlite3_mutex_notheld()] </li>
  5853. ** </ul>
  5854. **
  5855. ** The only difference is that the public sqlite3_XXX functions enumerated
  5856. ** above silently ignore any invocations that pass a NULL pointer instead
  5857. ** of a valid mutex handle. The implementations of the methods defined
  5858. ** by this structure are not required to handle this case, the results
  5859. ** of passing a NULL pointer instead of a valid mutex handle are undefined
  5860. ** (i.e. it is acceptable to provide an implementation that segfaults if
  5861. ** it is passed a NULL pointer).
  5862. */
  5863. typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
  5864. struct sqlite3_mutex_methods {
  5865. int (*xMutexInit)(void);
  5866. int (*xMutexEnd)(void);
  5867. sqlite3_mutex *(*xMutexAlloc)(int);
  5868. void (*xMutexFree)(sqlite3_mutex *);
  5869. void (*xMutexEnter)(sqlite3_mutex *);
  5870. int (*xMutexTry)(sqlite3_mutex *);
  5871. void (*xMutexLeave)(sqlite3_mutex *);
  5872. int (*xMutexHeld)(sqlite3_mutex *);
  5873. int (*xMutexNotheld)(sqlite3_mutex *);
  5874. };
  5875. /*
  5876. ** CAPI3REF: Mutex Verification Routines {H17080} <S20130> <S30800>
  5877. **
  5878. ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
  5879. ** are intended for use inside assert() statements. {H17081} The SQLite core
  5880. ** never uses these routines except inside an assert() and applications
  5881. ** are advised to follow the lead of the core. {H17082} The core only
  5882. ** provides implementations for these routines when it is compiled
  5883. ** with the SQLITE_DEBUG flag. {A17087} External mutex implementations
  5884. ** are only required to provide these routines if SQLITE_DEBUG is
  5885. ** defined and if NDEBUG is not defined.
  5886. **
  5887. ** {H17083} These routines should return true if the mutex in their argument
  5888. ** is held or not held, respectively, by the calling thread.
  5889. **
  5890. ** {X17084} The implementation is not required to provided versions of these
  5891. ** routines that actually work. If the implementation does not provide working
  5892. ** versions of these routines, it should at least provide stubs that always
  5893. ** return true so that one does not get spurious assertion failures.
  5894. **
  5895. ** {H17085} If the argument to sqlite3_mutex_held() is a NULL pointer then
  5896. ** the routine should return 1. {END} This seems counter-intuitive since
  5897. ** clearly the mutex cannot be held if it does not exist. But the
  5898. ** the reason the mutex does not exist is because the build is not
  5899. ** using mutexes. And we do not want the assert() containing the
  5900. ** call to sqlite3_mutex_held() to fail, so a non-zero return is
  5901. ** the appropriate thing to do. {H17086} The sqlite3_mutex_notheld()
  5902. ** interface should also return 1 when given a NULL pointer.
  5903. */
  5904. int sqlite3_mutex_held(sqlite3_mutex*);
  5905. int sqlite3_mutex_notheld(sqlite3_mutex*);
  5906. /*
  5907. ** CAPI3REF: Mutex Types {H17001} <H17000>
  5908. **
  5909. ** The [sqlite3_mutex_alloc()] interface takes a single argument
  5910. ** which is one of these integer constants.
  5911. **
  5912. ** The set of static mutexes may change from one SQLite release to the
  5913. ** next. Applications that override the built-in mutex logic must be
  5914. ** prepared to accommodate additional static mutexes.
  5915. */
  5916. #define SQLITE_MUTEX_FAST 0
  5917. #define SQLITE_MUTEX_RECURSIVE 1
  5918. #define SQLITE_MUTEX_STATIC_MASTER 2
  5919. #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
  5920. #define SQLITE_MUTEX_STATIC_MEM2 4 /* sqlite3_release_memory() */
  5921. #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */
  5922. #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
  5923. #define SQLITE_MUTEX_STATIC_LRU2 7 /* lru page list */
  5924. /*
  5925. ** CAPI3REF: Low-Level Control Of Database Files {H11300} <S30800>
  5926. **
  5927. ** {H11301} The [sqlite3_file_control()] interface makes a direct call to the
  5928. ** xFileControl method for the [sqlite3_io_methods] object associated
  5929. ** with a particular database identified by the second argument. {H11302} The
  5930. ** name of the database is the name assigned to the database by the
  5931. ** <a href="lang_attach.html">ATTACH</a> SQL command that opened the
  5932. ** database. {H11303} To control the main database file, use the name "main"
  5933. ** or a NULL pointer. {H11304} The third and fourth parameters to this routine
  5934. ** are passed directly through to the second and third parameters of
  5935. ** the xFileControl method. {H11305} The return value of the xFileControl
  5936. ** method becomes the return value of this routine.
  5937. **
  5938. ** {H11306} If the second parameter (zDbName) does not match the name of any
  5939. ** open database file, then SQLITE_ERROR is returned. {H11307} This error
  5940. ** code is not remembered and will not be recalled by [sqlite3_errcode()]
  5941. ** or [sqlite3_errmsg()]. {A11308} The underlying xFileControl method might
  5942. ** also return SQLITE_ERROR. {A11309} There is no way to distinguish between
  5943. ** an incorrect zDbName and an SQLITE_ERROR return from the underlying
  5944. ** xFileControl method. {END}
  5945. **
  5946. ** See also: [SQLITE_FCNTL_LOCKSTATE]
  5947. */
  5948. int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
  5949. /*
  5950. ** CAPI3REF: Testing Interface {H11400} <S30800>
  5951. **
  5952. ** The sqlite3_test_control() interface is used to read out internal
  5953. ** state of SQLite and to inject faults into SQLite for testing
  5954. ** purposes. The first parameter is an operation code that determines
  5955. ** the number, meaning, and operation of all subsequent parameters.
  5956. **
  5957. ** This interface is not for use by applications. It exists solely
  5958. ** for verifying the correct operation of the SQLite library. Depending
  5959. ** on how the SQLite library is compiled, this interface might not exist.
  5960. **
  5961. ** The details of the operation codes, their meanings, the parameters
  5962. ** they take, and what they do are all subject to change without notice.
  5963. ** Unlike most of the SQLite API, this function is not guaranteed to
  5964. ** operate consistently from one release to the next.
  5965. */
  5966. int sqlite3_test_control(int op, ...);
  5967. /*
  5968. ** CAPI3REF: Testing Interface Operation Codes {H11410} <H11400>
  5969. **
  5970. ** These constants are the valid operation code parameters used
  5971. ** as the first argument to [sqlite3_test_control()].
  5972. **
  5973. ** These parameters and their meanings are subject to change
  5974. ** without notice. These values are for testing purposes only.
  5975. ** Applications should not use any of these parameters or the
  5976. ** [sqlite3_test_control()] interface.
  5977. */
  5978. #define SQLITE_TESTCTRL_PRNG_SAVE 5
  5979. #define SQLITE_TESTCTRL_PRNG_RESTORE 6
  5980. #define SQLITE_TESTCTRL_PRNG_RESET 7
  5981. #define SQLITE_TESTCTRL_BITVEC_TEST 8
  5982. #define SQLITE_TESTCTRL_FAULT_INSTALL 9
  5983. #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
  5984. /*
  5985. ** CAPI3REF: SQLite Runtime Status {H17200} <S60200>
  5986. ** EXPERIMENTAL
  5987. **
  5988. ** This interface is used to retrieve runtime status information
  5989. ** about the preformance of SQLite, and optionally to reset various
  5990. ** highwater marks. The first argument is an integer code for
  5991. ** the specific parameter to measure. Recognized integer codes
  5992. ** are of the form [SQLITE_STATUS_MEMORY_USED | SQLITE_STATUS_...].
  5993. ** The current value of the parameter is returned into *pCurrent.
  5994. ** The highest recorded value is returned in *pHighwater. If the
  5995. ** resetFlag is true, then the highest record value is reset after
  5996. ** *pHighwater is written. Some parameters do not record the highest
  5997. ** value. For those parameters
  5998. ** nothing is written into *pHighwater and the resetFlag is ignored.
  5999. ** Other parameters record only the highwater mark and not the current
  6000. ** value. For these latter parameters nothing is written into *pCurrent.
  6001. **
  6002. ** This routine returns SQLITE_OK on success and a non-zero
  6003. ** [error code] on failure.
  6004. **
  6005. ** This routine is threadsafe but is not atomic. This routine can
  6006. ** called while other threads are running the same or different SQLite
  6007. ** interfaces. However the values returned in *pCurrent and
  6008. ** *pHighwater reflect the status of SQLite at different points in time
  6009. ** and it is possible that another thread might change the parameter
  6010. ** in between the times when *pCurrent and *pHighwater are written.
  6011. **
  6012. ** See also: [sqlite3_db_status()]
  6013. */
  6014. int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
  6015. /*
  6016. ** CAPI3REF: Database Connection Status {H17201} <S60200>
  6017. ** EXPERIMENTAL
  6018. **
  6019. ** This interface is used to retrieve runtime status information
  6020. ** about a single [database connection]. The first argument is the
  6021. ** database connection object to be interrogated. The second argument
  6022. ** is the parameter to interrogate. Currently, the only allowed value
  6023. ** for the second parameter is [SQLITE_DBSTATUS_LOOKASIDE_USED].
  6024. ** Additional options will likely appear in future releases of SQLite.
  6025. **
  6026. ** The current value of the request parameter is written into *pCur
  6027. ** and the highest instantaneous value is written into *pHiwtr. If
  6028. ** the resetFlg is true, then the highest instantaneous value is
  6029. ** reset back down to the current value.
  6030. **
  6031. ** See also: [sqlite3_status()].
  6032. */
  6033. int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
  6034. /*
  6035. ** CAPI3REF: Status Parameters {H17250} <H17200>
  6036. ** EXPERIMENTAL
  6037. **
  6038. ** These integer constants designate various run-time status parameters
  6039. ** that can be returned by [sqlite3_status()].
  6040. **
  6041. ** <dl>
  6042. ** <dt>SQLITE_STATUS_MEMORY_USED</dt>
  6043. ** <dd>This parameter is the current amount of memory checked out
  6044. ** using [sqlite3_malloc()], either directly or indirectly. The
  6045. ** figure includes calls made to [sqlite3_malloc()] by the application
  6046. ** and internal memory usage by the SQLite library. Scratch memory
  6047. ** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
  6048. ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
  6049. ** this parameter. The amount returned is the sum of the allocation
  6050. ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>
  6051. **
  6052. ** <dt>SQLITE_STATUS_MALLOC_SIZE</dt>
  6053. ** <dd>This parameter records the largest memory allocation request
  6054. ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
  6055. ** internal equivalents). Only the value returned in the
  6056. ** *pHighwater parameter to [sqlite3_status()] is of interest.
  6057. ** The value written into the *pCurrent parameter is undefined.</dd>
  6058. **
  6059. ** <dt>SQLITE_STATUS_PAGECACHE_USED</dt>
  6060. ** <dd>This parameter returns the number of pages used out of the
  6061. ** [pagecache memory allocator] that was configured using
  6062. ** [SQLITE_CONFIG_PAGECACHE]. The
  6063. ** value returned is in pages, not in bytes.</dd>
  6064. **
  6065. ** <dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
  6066. ** <dd>This parameter returns the number of bytes of page cache
  6067. ** allocation which could not be statisfied by the [SQLITE_CONFIG_PAGECACHE]
  6068. ** buffer and where forced to overflow to [sqlite3_malloc()]. The
  6069. ** returned value includes allocations that overflowed because they
  6070. ** where too large (they were larger than the "sz" parameter to
  6071. ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
  6072. ** no space was left in the page cache.</dd>
  6073. **
  6074. ** <dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
  6075. ** <dd>This parameter records the largest memory allocation request
  6076. ** handed to [pagecache memory allocator]. Only the value returned in the
  6077. ** *pHighwater parameter to [sqlite3_status()] is of interest.
  6078. ** The value written into the *pCurrent parameter is undefined.</dd>
  6079. **
  6080. ** <dt>SQLITE_STATUS_SCRATCH_USED</dt>
  6081. ** <dd>This parameter returns the number of allocations used out of the
  6082. ** [scratch memory allocator] configured using
  6083. ** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not
  6084. ** in bytes. Since a single thread may only have one scratch allocation
  6085. ** outstanding at time, this parameter also reports the number of threads
  6086. ** using scratch memory at the same time.</dd>
  6087. **
  6088. ** <dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
  6089. ** <dd>This parameter returns the number of bytes of scratch memory
  6090. ** allocation which could not be statisfied by the [SQLITE_CONFIG_SCRATCH]
  6091. ** buffer and where forced to overflow to [sqlite3_malloc()]. The values
  6092. ** returned include overflows because the requested allocation was too
  6093. ** larger (that is, because the requested allocation was larger than the
  6094. ** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
  6095. ** slots were available.
  6096. ** </dd>
  6097. **
  6098. ** <dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
  6099. ** <dd>This parameter records the largest memory allocation request
  6100. ** handed to [scratch memory allocator]. Only the value returned in the
  6101. ** *pHighwater parameter to [sqlite3_status()] is of interest.
  6102. ** The value written into the *pCurrent parameter is undefined.</dd>
  6103. **
  6104. ** <dt>SQLITE_STATUS_PARSER_STACK</dt>
  6105. ** <dd>This parameter records the deepest parser stack. It is only
  6106. ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>
  6107. ** </dl>
  6108. **
  6109. ** New status parameters may be added from time to time.
  6110. */
  6111. #define SQLITE_STATUS_MEMORY_USED 0
  6112. #define SQLITE_STATUS_PAGECACHE_USED 1
  6113. #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2
  6114. #define SQLITE_STATUS_SCRATCH_USED 3
  6115. #define SQLITE_STATUS_SCRATCH_OVERFLOW 4
  6116. #define SQLITE_STATUS_MALLOC_SIZE 5
  6117. #define SQLITE_STATUS_PARSER_STACK 6
  6118. #define SQLITE_STATUS_PAGECACHE_SIZE 7
  6119. #define SQLITE_STATUS_SCRATCH_SIZE 8
  6120. /*
  6121. ** CAPI3REF: Status Parameters for database connections {H17275} <H17200>
  6122. ** EXPERIMENTAL
  6123. **
  6124. ** Status verbs for [sqlite3_db_status()].
  6125. **
  6126. ** <dl>
  6127. ** <dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
  6128. ** <dd>This parameter returns the number of lookaside memory slots currently
  6129. ** checked out.</dd>
  6130. ** </dl>
  6131. */
  6132. #define SQLITE_DBSTATUS_LOOKASIDE_USED 0
  6133. /*
  6134. ** Undo the hack that converts floating point types to integer for
  6135. ** builds on processors without floating point support.
  6136. */
  6137. #ifdef SQLITE_OMIT_FLOATING_POINT
  6138. # undef double
  6139. #endif
  6140. #ifdef __cplusplus
  6141. } /* End of the 'extern "C"' block */
  6142. #endif
  6143. #endif