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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 the right to make minor changes | |
| 22 ** if experience from use "in the wild" suggest such changes are prudent. | |
| 23 ** | |
| 24 ** The official C-language API documentation for SQLite is derived | |
| 25 ** from comments in this file. This file is the authoritative source | |
| 26 ** on how SQLite interfaces are 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 #ifndef _SQLITE3_H_ | |
| 34 #define _SQLITE3_H_ | |
| 35 #include <stdarg.h> /* Needed for the definition of va_list */ | |
| 36 | |
| 37 /* | |
| 38 ** Make sure we can call this stuff from C++. | |
| 39 */ | |
| 40 #ifdef __cplusplus | |
| 41 extern "C" { | |
| 42 #endif | |
| 43 | |
| 44 | |
| 45 /* | |
| 46 ** Add the ability to override 'extern' | |
| 47 */ | |
| 48 #ifndef SQLITE_EXTERN | |
| 49 # define SQLITE_EXTERN extern | |
| 50 #endif | |
| 51 | |
| 52 #ifndef SQLITE_API | |
| 53 # define SQLITE_API | |
| 54 #endif | |
| 55 | |
| 56 | |
| 57 /* | |
| 58 ** These no-op macros are used in front of interfaces to mark those | |
| 59 ** interfaces as either deprecated or experimental. New applications | |
| 60 ** should not use deprecated interfaces - they are support for backwards | |
| 61 ** compatibility only. Application writers should be aware that | |
| 62 ** experimental interfaces are subject to change in point releases. | |
| 63 ** | |
| 64 ** These macros used to resolve to various kinds of compiler magic that | |
| 65 ** would generate warning messages when they were used. But that | |
| 66 ** compiler magic ended up generating such a flurry of bug reports | |
| 67 ** that we have taken it all out and gone back to using simple | |
| 68 ** noop macros. | |
| 69 */ | |
| 70 #define SQLITE_DEPRECATED | |
| 71 #define SQLITE_EXPERIMENTAL | |
| 72 | |
| 73 /* | |
| 74 ** Ensure these symbols were not defined by some previous header file. | |
| 75 */ | |
| 76 #ifdef SQLITE_VERSION | |
| 77 # undef SQLITE_VERSION | |
| 78 #endif | |
| 79 #ifdef SQLITE_VERSION_NUMBER | |
| 80 # undef SQLITE_VERSION_NUMBER | |
| 81 #endif | |
| 82 | |
| 83 /* | |
| 84 ** CAPI3REF: Compile-Time Library Version Numbers {H10010} <S60100> | |
| 85 ** | |
| 86 ** The SQLITE_VERSION and SQLITE_VERSION_NUMBER #defines in | |
| 87 ** the sqlite3.h file specify the version of SQLite with which | |
| 88 ** that header file is associated. | |
| 89 ** | |
| 90 ** The "version" of SQLite is a string of the form "W.X.Y" or "W.X.Y.Z". | |
| 91 ** The W value is major version number and is always 3 in SQLite3. | |
| 92 ** The W value only changes when backwards compatibility is | |
| 93 ** broken and we intend to never break backwards compatibility. | |
| 94 ** The X value is the minor version number and only changes when | |
| 95 ** there are major feature enhancements that are forwards compatible | |
| 96 ** but not backwards compatible. | |
| 97 ** The Y value is the release number and is incremented with | |
| 98 ** each release but resets back to 0 whenever X is incremented. | |
| 99 ** The Z value only appears on branch releases. | |
| 100 ** | |
| 101 ** The SQLITE_VERSION_NUMBER is an integer that is computed as | |
| 102 ** follows: | |
| 103 ** | |
| 104 ** <blockquote><pre> | |
| 105 ** SQLITE_VERSION_NUMBER = W*1000000 + X*1000 + Y | |
| 106 ** </pre></blockquote> | |
| 107 ** | |
| 108 ** Since version 3.6.18, SQLite source code has been stored in the | |
| 109 ** <a href="http://www.fossil-scm.org/">fossil configuration management | |
| 110 ** system</a>. The SQLITE_SOURCE_ID | |
| 111 ** macro is a string which identifies a particular check-in of SQLite | |
| 112 ** within its configuration management system. The string contains the | |
| 113 ** date and time of the check-in (UTC) and an SHA1 hash of the entire | |
| 114 ** source tree. | |
| 115 ** | |
| 116 ** See also: [sqlite3_libversion()], | |
| 117 ** [sqlite3_libversion_number()], [sqlite3_sourceid()], | |
| 118 ** [sqlite_version()] and [sqlite_source_id()]. | |
| 119 ** | |
| 120 ** Requirements: [H10011] [H10014] | |
| 121 */ | |
| 122 #define SQLITE_VERSION "3.6.18" | |
| 123 #define SQLITE_VERSION_NUMBER 3006018 | |
| 124 #define SQLITE_SOURCE_ID "2009-09-11 14:05:07 b084828a771ec40be85f07c590ca9
9de4f6c24ee" | |
| 125 | |
| 126 /* | |
| 127 ** CAPI3REF: Run-Time Library Version Numbers {H10020} <S60100> | |
| 128 ** KEYWORDS: sqlite3_version | |
| 129 ** | |
| 130 ** These interfaces provide the same information as the [SQLITE_VERSION], | |
| 131 ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] #defines in the header, | |
| 132 ** but are associated with the library instead of the header file. Cautious | |
| 133 ** programmers might include assert() statements in their application to | |
| 134 ** verify that values returned by these interfaces match the macros in | |
| 135 ** the header, and thus insure that the application is | |
| 136 ** compiled with matching library and header files. | |
| 137 ** | |
| 138 ** <blockquote><pre> | |
| 139 ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER ); | |
| 140 ** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 ); | |
| 141 ** assert( strcmp(sqlite3_libversion,SQLITE_VERSION)==0 ); | |
| 142 ** </pre></blockquote> | |
| 143 ** | |
| 144 ** The sqlite3_libversion() function returns the same information as is | |
| 145 ** in the sqlite3_version[] string constant. The function is provided | |
| 146 ** for use in DLLs since DLL users usually do not have direct access to string | |
| 147 ** constants within the DLL. Similarly, the sqlite3_sourceid() function | |
| 148 ** returns the same information as is in the [SQLITE_SOURCE_ID] #define of | |
| 149 ** the header file. | |
| 150 ** | |
| 151 ** See also: [sqlite_version()] and [sqlite_source_id()]. | |
| 152 ** | |
| 153 ** Requirements: [H10021] [H10022] [H10023] | |
| 154 */ | |
| 155 SQLITE_API SQLITE_EXTERN const char sqlite3_version[]; | |
| 156 SQLITE_API const char *sqlite3_libversion(void); | |
| 157 SQLITE_API const char *sqlite3_sourceid(void); | |
| 158 SQLITE_API int sqlite3_libversion_number(void); | |
| 159 | |
| 160 /* | |
| 161 ** CAPI3REF: Test To See If The Library Is Threadsafe {H10100} <S60100> | |
| 162 ** | |
| 163 ** SQLite can be compiled with or without mutexes. When | |
| 164 ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes | |
| 165 ** are enabled and SQLite is threadsafe. When the | |
| 166 ** [SQLITE_THREADSAFE] macro is 0, | |
| 167 ** the mutexes are omitted. Without the mutexes, it is not safe | |
| 168 ** to use SQLite concurrently from more than one thread. | |
| 169 ** | |
| 170 ** Enabling mutexes incurs a measurable performance penalty. | |
| 171 ** So if speed is of utmost importance, it makes sense to disable | |
| 172 ** the mutexes. But for maximum safety, mutexes should be enabled. | |
| 173 ** The default behavior is for mutexes to be enabled. | |
| 174 ** | |
| 175 ** This interface can be used by an application to make sure that the | |
| 176 ** version of SQLite that it is linking against was compiled with | |
| 177 ** the desired setting of the [SQLITE_THREADSAFE] macro. | |
| 178 ** | |
| 179 ** This interface only reports on the compile-time mutex setting | |
| 180 ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with | |
| 181 ** SQLITE_THREADSAFE=1 then mutexes are enabled by default but | |
| 182 ** can be fully or partially disabled using a call to [sqlite3_config()] | |
| 183 ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD], | |
| 184 ** or [SQLITE_CONFIG_MUTEX]. The return value of this function shows | |
| 185 ** only the default compile-time setting, not any run-time changes | |
| 186 ** to that setting. | |
| 187 ** | |
| 188 ** See the [threading mode] documentation for additional information. | |
| 189 ** | |
| 190 ** Requirements: [H10101] [H10102] | |
| 191 */ | |
| 192 SQLITE_API int sqlite3_threadsafe(void); | |
| 193 | |
| 194 /* | |
| 195 ** CAPI3REF: Database Connection Handle {H12000} <S40200> | |
| 196 ** KEYWORDS: {database connection} {database connections} | |
| 197 ** | |
| 198 ** Each open SQLite database is represented by a pointer to an instance of | |
| 199 ** the opaque structure named "sqlite3". It is useful to think of an sqlite3 | |
| 200 ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and | |
| 201 ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()] | |
| 202 ** is its destructor. There are many other interfaces (such as | |
| 203 ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and | |
| 204 ** [sqlite3_busy_timeout()] to name but three) that are methods on an | |
| 205 ** sqlite3 object. | |
| 206 */ | |
| 207 typedef struct sqlite3 sqlite3; | |
| 208 | |
| 209 /* | |
| 210 ** CAPI3REF: 64-Bit Integer Types {H10200} <S10110> | |
| 211 ** KEYWORDS: sqlite_int64 sqlite_uint64 | |
| 212 ** | |
| 213 ** Because there is no cross-platform way to specify 64-bit integer types | |
| 214 ** SQLite includes typedefs for 64-bit signed and unsigned integers. | |
| 215 ** | |
| 216 ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions. | |
| 217 ** The sqlite_int64 and sqlite_uint64 types are supported for backwards | |
| 218 ** compatibility only. | |
| 219 ** | |
| 220 ** Requirements: [H10201] [H10202] | |
| 221 */ | |
| 222 #ifdef SQLITE_INT64_TYPE | |
| 223 typedef SQLITE_INT64_TYPE sqlite_int64; | |
| 224 typedef unsigned SQLITE_INT64_TYPE sqlite_uint64; | |
| 225 #elif defined(_MSC_VER) || defined(__BORLANDC__) | |
| 226 typedef __int64 sqlite_int64; | |
| 227 typedef unsigned __int64 sqlite_uint64; | |
| 228 #else | |
| 229 typedef long long int sqlite_int64; | |
| 230 typedef unsigned long long int sqlite_uint64; | |
| 231 #endif | |
| 232 typedef sqlite_int64 sqlite3_int64; | |
| 233 typedef sqlite_uint64 sqlite3_uint64; | |
| 234 | |
| 235 /* | |
| 236 ** If compiling for a processor that lacks floating point support, | |
| 237 ** substitute integer for floating-point. | |
| 238 */ | |
| 239 #ifdef SQLITE_OMIT_FLOATING_POINT | |
| 240 # define double sqlite3_int64 | |
| 241 #endif | |
| 242 | |
| 243 /* | |
| 244 ** CAPI3REF: Closing A Database Connection {H12010} <S30100><S40200> | |
| 245 ** | |
| 246 ** This routine is the destructor for the [sqlite3] object. | |
| 247 ** | |
| 248 ** Applications should [sqlite3_finalize | finalize] all [prepared statements] | |
| 249 ** and [sqlite3_blob_close | close] all [BLOB handles] associated with | |
| 250 ** the [sqlite3] object prior to attempting to close the object. | |
| 251 ** The [sqlite3_next_stmt()] interface can be used to locate all | |
| 252 ** [prepared statements] associated with a [database connection] if desired. | |
| 253 ** Typical code might look like this: | |
| 254 ** | |
| 255 ** <blockquote><pre> | |
| 256 ** sqlite3_stmt *pStmt; | |
| 257 ** while( (pStmt = sqlite3_next_stmt(db, 0))!=0 ){ | |
| 258 ** sqlite3_finalize(pStmt); | |
| 259 ** } | |
| 260 ** </pre></blockquote> | |
| 261 ** | |
| 262 ** If [sqlite3_close()] is invoked while a transaction is open, | |
| 263 ** the transaction is automatically rolled back. | |
| 264 ** | |
| 265 ** The C parameter to [sqlite3_close(C)] must be either a NULL | |
| 266 ** pointer or an [sqlite3] object pointer obtained | |
| 267 ** from [sqlite3_open()], [sqlite3_open16()], or | |
| 268 ** [sqlite3_open_v2()], and not previously closed. | |
| 269 ** | |
| 270 ** Requirements: | |
| 271 ** [H12011] [H12012] [H12013] [H12014] [H12015] [H12019] | |
| 272 */ | |
| 273 SQLITE_API int sqlite3_close(sqlite3 *); | |
| 274 | |
| 275 /* | |
| 276 ** The type for a callback function. | |
| 277 ** This is legacy and deprecated. It is included for historical | |
| 278 ** compatibility and is not documented. | |
| 279 */ | |
| 280 typedef int (*sqlite3_callback)(void*,int,char**, char**); | |
| 281 | |
| 282 /* | |
| 283 ** CAPI3REF: One-Step Query Execution Interface {H12100} <S10000> | |
| 284 ** | |
| 285 ** The sqlite3_exec() interface is a convenient way of running one or more | |
| 286 ** SQL statements without having to write a lot of C code. The UTF-8 encoded | |
| 287 ** SQL statements are passed in as the second parameter to sqlite3_exec(). | |
| 288 ** The statements are evaluated one by one until either an error or | |
| 289 ** an interrupt is encountered, or until they are all done. The 3rd parameter | |
| 290 ** is an optional callback that is invoked once for each row of any query | |
| 291 ** results produced by the SQL statements. The 5th parameter tells where | |
| 292 ** to write any error messages. | |
| 293 ** | |
| 294 ** The error message passed back through the 5th parameter is held | |
| 295 ** in memory obtained from [sqlite3_malloc()]. To avoid a memory leak, | |
| 296 ** the calling application should call [sqlite3_free()] on any error | |
| 297 ** message returned through the 5th parameter when it has finished using | |
| 298 ** the error message. | |
| 299 ** | |
| 300 ** If the SQL statement in the 2nd parameter is NULL or an empty string | |
| 301 ** or a string containing only whitespace and comments, then no SQL | |
| 302 ** statements are evaluated and the database is not changed. | |
| 303 ** | |
| 304 ** The sqlite3_exec() interface is implemented in terms of | |
| 305 ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()]. | |
| 306 ** The sqlite3_exec() routine does nothing to the database that cannot be done | |
| 307 ** by [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()]. | |
| 308 ** | |
| 309 ** The first parameter to [sqlite3_exec()] must be an valid and open | |
| 310 ** [database connection]. | |
| 311 ** | |
| 312 ** The database connection must not be closed while | |
| 313 ** [sqlite3_exec()] is running. | |
| 314 ** | |
| 315 ** The calling function should use [sqlite3_free()] to free | |
| 316 ** the memory that *errmsg is left pointing at once the error | |
| 317 ** message is no longer needed. | |
| 318 ** | |
| 319 ** The SQL statement text in the 2nd parameter to [sqlite3_exec()] | |
| 320 ** must remain unchanged while [sqlite3_exec()] is running. | |
| 321 ** | |
| 322 ** Requirements: | |
| 323 ** [H12101] [H12102] [H12104] [H12105] [H12107] [H12110] [H12113] [H12116] | |
| 324 ** [H12119] [H12122] [H12125] [H12131] [H12134] [H12137] [H12138] | |
| 325 */ | |
| 326 SQLITE_API int sqlite3_exec( | |
| 327 sqlite3*, /* An open database */ | |
| 328 const char *sql, /* SQL to be evaluated */ | |
| 329 int (*callback)(void*,int,char**,char**), /* Callback function */ | |
| 330 void *, /* 1st argument to callback */ | |
| 331 char **errmsg /* Error msg written here */ | |
| 332 ); | |
| 333 | |
| 334 /* | |
| 335 ** CAPI3REF: Result Codes {H10210} <S10700> | |
| 336 ** KEYWORDS: SQLITE_OK {error code} {error codes} | |
| 337 ** KEYWORDS: {result code} {result codes} | |
| 338 ** | |
| 339 ** Many SQLite functions return an integer result code from the set shown | |
| 340 ** here in order to indicates success or failure. | |
| 341 ** | |
| 342 ** New error codes may be added in future versions of SQLite. | |
| 343 ** | |
| 344 ** See also: [SQLITE_IOERR_READ | extended result codes] | |
| 345 */ | |
| 346 #define SQLITE_OK 0 /* Successful result */ | |
| 347 /* beginning-of-error-codes */ | |
| 348 #define SQLITE_ERROR 1 /* SQL error or missing database */ | |
| 349 #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */ | |
| 350 #define SQLITE_PERM 3 /* Access permission denied */ | |
| 351 #define SQLITE_ABORT 4 /* Callback routine requested an abort */ | |
| 352 #define SQLITE_BUSY 5 /* The database file is locked */ | |
| 353 #define SQLITE_LOCKED 6 /* A table in the database is locked */ | |
| 354 #define SQLITE_NOMEM 7 /* A malloc() failed */ | |
| 355 #define SQLITE_READONLY 8 /* Attempt to write a readonly database */ | |
| 356 #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/ | |
| 357 #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ | |
| 358 #define SQLITE_CORRUPT 11 /* The database disk image is malformed */ | |
| 359 #define SQLITE_NOTFOUND 12 /* NOT USED. Table or record not found */ | |
| 360 #define SQLITE_FULL 13 /* Insertion failed because database is full */ | |
| 361 #define SQLITE_CANTOPEN 14 /* Unable to open the database file */ | |
| 362 #define SQLITE_PROTOCOL 15 /* NOT USED. Database lock protocol error */ | |
| 363 #define SQLITE_EMPTY 16 /* Database is empty */ | |
| 364 #define SQLITE_SCHEMA 17 /* The database schema changed */ | |
| 365 #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */ | |
| 366 #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */ | |
| 367 #define SQLITE_MISMATCH 20 /* Data type mismatch */ | |
| 368 #define SQLITE_MISUSE 21 /* Library used incorrectly */ | |
| 369 #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ | |
| 370 #define SQLITE_AUTH 23 /* Authorization denied */ | |
| 371 #define SQLITE_FORMAT 24 /* Auxiliary database format error */ | |
| 372 #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */ | |
| 373 #define SQLITE_NOTADB 26 /* File opened that is not a database file */ | |
| 374 #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */ | |
| 375 #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */ | |
| 376 /* end-of-error-codes */ | |
| 377 | |
| 378 /* | |
| 379 ** CAPI3REF: Extended Result Codes {H10220} <S10700> | |
| 380 ** KEYWORDS: {extended error code} {extended error codes} | |
| 381 ** KEYWORDS: {extended result code} {extended result codes} | |
| 382 ** | |
| 383 ** In its default configuration, SQLite API routines return one of 26 integer | |
| 384 ** [SQLITE_OK | result codes]. However, experience has shown that many of | |
| 385 ** these result codes are too coarse-grained. They do not provide as | |
| 386 ** much information about problems as programmers might like. In an effort to | |
| 387 ** address this, newer versions of SQLite (version 3.3.8 and later) include | |
| 388 ** support for additional result codes that provide more detailed information | |
| 389 ** about errors. The extended result codes are enabled or disabled | |
| 390 ** on a per database connection basis using the | |
| 391 ** [sqlite3_extended_result_codes()] API. | |
| 392 ** | |
| 393 ** Some of the available extended result codes are listed here. | |
| 394 ** One may expect the number of extended result codes will be expand | |
| 395 ** over time. Software that uses extended result codes should expect | |
| 396 ** to see new result codes in future releases of SQLite. | |
| 397 ** | |
| 398 ** The SQLITE_OK result code will never be extended. It will always | |
| 399 ** be exactly zero. | |
| 400 */ | |
| 401 #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) | |
| 402 #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) | |
| 403 #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) | |
| 404 #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) | |
| 405 #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) | |
| 406 #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) | |
| 407 #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) | |
| 408 #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) | |
| 409 #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) | |
| 410 #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) | |
| 411 #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) | |
| 412 #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) | |
| 413 #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8)) | |
| 414 #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8)) | |
| 415 #define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8)) | |
| 416 #define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8)) | |
| 417 #define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8)) | |
| 418 #define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8) ) | |
| 419 | |
| 420 /* | |
| 421 ** CAPI3REF: Flags For File Open Operations {H10230} <H11120> <H12700> | |
| 422 ** | |
| 423 ** These bit values are intended for use in the | |
| 424 ** 3rd parameter to the [sqlite3_open_v2()] interface and | |
| 425 ** in the 4th parameter to the xOpen method of the | |
| 426 ** [sqlite3_vfs] object. | |
| 427 */ | |
| 428 #define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */ | |
| 429 #define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */ | |
| 430 #define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */ | |
| 431 #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */ | |
| 432 #define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */ | |
| 433 #define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */ | |
| 434 #define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */ | |
| 435 #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */ | |
| 436 #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */ | |
| 437 #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */ | |
| 438 #define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */ | |
| 439 #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */ | |
| 440 #define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */ | |
| 441 #define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */ | |
| 442 #define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */ | |
| 443 #define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */ | |
| 444 | |
| 445 /* | |
| 446 ** CAPI3REF: Device Characteristics {H10240} <H11120> | |
| 447 ** | |
| 448 ** The xDeviceCapabilities method of the [sqlite3_io_methods] | |
| 449 ** object returns an integer which is a vector of the these | |
| 450 ** bit values expressing I/O characteristics of the mass storage | |
| 451 ** device that holds the file that the [sqlite3_io_methods] | |
| 452 ** refers to. | |
| 453 ** | |
| 454 ** The SQLITE_IOCAP_ATOMIC property means that all writes of | |
| 455 ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values | |
| 456 ** mean that writes of blocks that are nnn bytes in size and | |
| 457 ** are aligned to an address which is an integer multiple of | |
| 458 ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means | |
| 459 ** that when data is appended to a file, the data is appended | |
| 460 ** first then the size of the file is extended, never the other | |
| 461 ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that | |
| 462 ** information is written to disk in the same order as calls | |
| 463 ** to xWrite(). | |
| 464 */ | |
| 465 #define SQLITE_IOCAP_ATOMIC 0x00000001 | |
| 466 #define SQLITE_IOCAP_ATOMIC512 0x00000002 | |
| 467 #define SQLITE_IOCAP_ATOMIC1K 0x00000004 | |
| 468 #define SQLITE_IOCAP_ATOMIC2K 0x00000008 | |
| 469 #define SQLITE_IOCAP_ATOMIC4K 0x00000010 | |
| 470 #define SQLITE_IOCAP_ATOMIC8K 0x00000020 | |
| 471 #define SQLITE_IOCAP_ATOMIC16K 0x00000040 | |
| 472 #define SQLITE_IOCAP_ATOMIC32K 0x00000080 | |
| 473 #define SQLITE_IOCAP_ATOMIC64K 0x00000100 | |
| 474 #define SQLITE_IOCAP_SAFE_APPEND 0x00000200 | |
| 475 #define SQLITE_IOCAP_SEQUENTIAL 0x00000400 | |
| 476 | |
| 477 /* | |
| 478 ** CAPI3REF: File Locking Levels {H10250} <H11120> <H11310> | |
| 479 ** | |
| 480 ** SQLite uses one of these integer values as the second | |
| 481 ** argument to calls it makes to the xLock() and xUnlock() methods | |
| 482 ** of an [sqlite3_io_methods] object. | |
| 483 */ | |
| 484 #define SQLITE_LOCK_NONE 0 | |
| 485 #define SQLITE_LOCK_SHARED 1 | |
| 486 #define SQLITE_LOCK_RESERVED 2 | |
| 487 #define SQLITE_LOCK_PENDING 3 | |
| 488 #define SQLITE_LOCK_EXCLUSIVE 4 | |
| 489 | |
| 490 /* | |
| 491 ** CAPI3REF: Synchronization Type Flags {H10260} <H11120> | |
| 492 ** | |
| 493 ** When SQLite invokes the xSync() method of an | |
| 494 ** [sqlite3_io_methods] object it uses a combination of | |
| 495 ** these integer values as the second argument. | |
| 496 ** | |
| 497 ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the | |
| 498 ** sync operation only needs to flush data to mass storage. Inode | |
| 499 ** information need not be flushed. If the lower four bits of the flag | |
| 500 ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics. | |
| 501 ** If the lower four bits equal SQLITE_SYNC_FULL, that means | |
| 502 ** to use Mac OS X style fullsync instead of fsync(). | |
| 503 */ | |
| 504 #define SQLITE_SYNC_NORMAL 0x00002 | |
| 505 #define SQLITE_SYNC_FULL 0x00003 | |
| 506 #define SQLITE_SYNC_DATAONLY 0x00010 | |
| 507 | |
| 508 /* | |
| 509 ** CAPI3REF: OS Interface Open File Handle {H11110} <S20110> | |
| 510 ** | |
| 511 ** An [sqlite3_file] object represents an open file in the | |
| 512 ** [sqlite3_vfs | OS interface layer]. Individual OS interface | |
| 513 ** implementations will | |
| 514 ** want to subclass this object by appending additional fields | |
| 515 ** for their own use. The pMethods entry is a pointer to an | |
| 516 ** [sqlite3_io_methods] object that defines methods for performing | |
| 517 ** I/O operations on the open file. | |
| 518 */ | |
| 519 typedef struct sqlite3_file sqlite3_file; | |
| 520 struct sqlite3_file { | |
| 521 const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ | |
| 522 }; | |
| 523 | |
| 524 /* | |
| 525 ** CAPI3REF: OS Interface File Virtual Methods Object {H11120} <S20110> | |
| 526 ** | |
| 527 ** Every file opened by the [sqlite3_vfs] xOpen method populates an | |
| 528 ** [sqlite3_file] object (or, more commonly, a subclass of the | |
| 529 ** [sqlite3_file] object) with a pointer to an instance of this object. | |
| 530 ** This object defines the methods used to perform various operations | |
| 531 ** against the open file represented by the [sqlite3_file] object. | |
| 532 ** | |
| 533 ** If the xOpen method sets the sqlite3_file.pMethods element | |
| 534 ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method | |
| 535 ** may be invoked even if the xOpen reported that it failed. The | |
| 536 ** only way to prevent a call to xClose following a failed xOpen | |
| 537 ** is for the xOpen to set the sqlite3_file.pMethods element to NULL. | |
| 538 ** | |
| 539 ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or | |
| 540 ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). | |
| 541 ** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY] | |
| 542 ** flag may be ORed in to indicate that only the data of the file | |
| 543 ** and not its inode needs to be synced. | |
| 544 ** | |
| 545 ** The integer values to xLock() and xUnlock() are one of | |
| 546 ** <ul> | |
| 547 ** <li> [SQLITE_LOCK_NONE], | |
| 548 ** <li> [SQLITE_LOCK_SHARED], | |
| 549 ** <li> [SQLITE_LOCK_RESERVED], | |
| 550 ** <li> [SQLITE_LOCK_PENDING], or | |
| 551 ** <li> [SQLITE_LOCK_EXCLUSIVE]. | |
| 552 ** </ul> | |
| 553 ** xLock() increases the lock. xUnlock() decreases the lock. | |
| 554 ** The xCheckReservedLock() method checks whether any database connection, | |
| 555 ** either in this process or in some other process, is holding a RESERVED, | |
| 556 ** PENDING, or EXCLUSIVE lock on the file. It returns true | |
| 557 ** if such a lock exists and false otherwise. | |
| 558 ** | |
| 559 ** The xFileControl() method is a generic interface that allows custom | |
| 560 ** VFS implementations to directly control an open file using the | |
| 561 ** [sqlite3_file_control()] interface. The second "op" argument is an | |
| 562 ** integer opcode. The third argument is a generic pointer intended to | |
| 563 ** point to a structure that may contain arguments or space in which to | |
| 564 ** write return values. Potential uses for xFileControl() might be | |
| 565 ** functions to enable blocking locks with timeouts, to change the | |
| 566 ** locking strategy (for example to use dot-file locks), to inquire | |
| 567 ** about the status of a lock, or to break stale locks. The SQLite | |
| 568 ** core reserves all opcodes less than 100 for its own use. | |
| 569 ** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available. | |
| 570 ** Applications that define a custom xFileControl method should use opcodes | |
| 571 ** greater than 100 to avoid conflicts. | |
| 572 ** | |
| 573 ** The xSectorSize() method returns the sector size of the | |
| 574 ** device that underlies the file. The sector size is the | |
| 575 ** minimum write that can be performed without disturbing | |
| 576 ** other bytes in the file. The xDeviceCharacteristics() | |
| 577 ** method returns a bit vector describing behaviors of the | |
| 578 ** underlying device: | |
| 579 ** | |
| 580 ** <ul> | |
| 581 ** <li> [SQLITE_IOCAP_ATOMIC] | |
| 582 ** <li> [SQLITE_IOCAP_ATOMIC512] | |
| 583 ** <li> [SQLITE_IOCAP_ATOMIC1K] | |
| 584 ** <li> [SQLITE_IOCAP_ATOMIC2K] | |
| 585 ** <li> [SQLITE_IOCAP_ATOMIC4K] | |
| 586 ** <li> [SQLITE_IOCAP_ATOMIC8K] | |
| 587 ** <li> [SQLITE_IOCAP_ATOMIC16K] | |
| 588 ** <li> [SQLITE_IOCAP_ATOMIC32K] | |
| 589 ** <li> [SQLITE_IOCAP_ATOMIC64K] | |
| 590 ** <li> [SQLITE_IOCAP_SAFE_APPEND] | |
| 591 ** <li> [SQLITE_IOCAP_SEQUENTIAL] | |
| 592 ** </ul> | |
| 593 ** | |
| 594 ** The SQLITE_IOCAP_ATOMIC property means that all writes of | |
| 595 ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values | |
| 596 ** mean that writes of blocks that are nnn bytes in size and | |
| 597 ** are aligned to an address which is an integer multiple of | |
| 598 ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means | |
| 599 ** that when data is appended to a file, the data is appended | |
| 600 ** first then the size of the file is extended, never the other | |
| 601 ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that | |
| 602 ** information is written to disk in the same order as calls | |
| 603 ** to xWrite(). | |
| 604 ** | |
| 605 ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill | |
| 606 ** in the unread portions of the buffer with zeros. A VFS that | |
| 607 ** fails to zero-fill short reads might seem to work. However, | |
| 608 ** failure to zero-fill short reads will eventually lead to | |
| 609 ** database corruption. | |
| 610 */ | |
| 611 typedef struct sqlite3_io_methods sqlite3_io_methods; | |
| 612 struct sqlite3_io_methods { | |
| 613 int iVersion; | |
| 614 int (*xClose)(sqlite3_file*); | |
| 615 int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); | |
| 616 int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); | |
| 617 int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); | |
| 618 int (*xSync)(sqlite3_file*, int flags); | |
| 619 int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); | |
| 620 int (*xLock)(sqlite3_file*, int); | |
| 621 int (*xUnlock)(sqlite3_file*, int); | |
| 622 int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); | |
| 623 int (*xFileControl)(sqlite3_file*, int op, void *pArg); | |
| 624 int (*xSectorSize)(sqlite3_file*); | |
| 625 int (*xDeviceCharacteristics)(sqlite3_file*); | |
| 626 /* Additional methods may be added in future releases */ | |
| 627 }; | |
| 628 | |
| 629 /* | |
| 630 ** CAPI3REF: Standard File Control Opcodes {H11310} <S30800> | |
| 631 ** | |
| 632 ** These integer constants are opcodes for the xFileControl method | |
| 633 ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] | |
| 634 ** interface. | |
| 635 ** | |
| 636 ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This | |
| 637 ** opcode causes the xFileControl method to write the current state of | |
| 638 ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED], | |
| 639 ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE]) | |
| 640 ** into an integer that the pArg argument points to. This capability | |
| 641 ** is used during testing and only needs to be supported when SQLITE_TEST | |
| 642 ** is defined. | |
| 643 */ | |
| 644 #define SQLITE_FCNTL_LOCKSTATE 1 | |
| 645 #define SQLITE_GET_LOCKPROXYFILE 2 | |
| 646 #define SQLITE_SET_LOCKPROXYFILE 3 | |
| 647 #define SQLITE_LAST_ERRNO 4 | |
| 648 | |
| 649 /* | |
| 650 ** CAPI3REF: Mutex Handle {H17110} <S20130> | |
| 651 ** | |
| 652 ** The mutex module within SQLite defines [sqlite3_mutex] to be an | |
| 653 ** abstract type for a mutex object. The SQLite core never looks | |
| 654 ** at the internal representation of an [sqlite3_mutex]. It only | |
| 655 ** deals with pointers to the [sqlite3_mutex] object. | |
| 656 ** | |
| 657 ** Mutexes are created using [sqlite3_mutex_alloc()]. | |
| 658 */ | |
| 659 typedef struct sqlite3_mutex sqlite3_mutex; | |
| 660 | |
| 661 /* | |
| 662 ** CAPI3REF: OS Interface Object {H11140} <S20100> | |
| 663 ** | |
| 664 ** An instance of the sqlite3_vfs object defines the interface between | |
| 665 ** the SQLite core and the underlying operating system. The "vfs" | |
| 666 ** in the name of the object stands for "virtual file system". | |
| 667 ** | |
| 668 ** The value of the iVersion field is initially 1 but may be larger in | |
| 669 ** future versions of SQLite. Additional fields may be appended to this | |
| 670 ** object when the iVersion value is increased. Note that the structure | |
| 671 ** of the sqlite3_vfs object changes in the transaction between | |
| 672 ** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not | |
| 673 ** modified. | |
| 674 ** | |
| 675 ** The szOsFile field is the size of the subclassed [sqlite3_file] | |
| 676 ** structure used by this VFS. mxPathname is the maximum length of | |
| 677 ** a pathname in this VFS. | |
| 678 ** | |
| 679 ** Registered sqlite3_vfs objects are kept on a linked list formed by | |
| 680 ** the pNext pointer. The [sqlite3_vfs_register()] | |
| 681 ** and [sqlite3_vfs_unregister()] interfaces manage this list | |
| 682 ** in a thread-safe way. The [sqlite3_vfs_find()] interface | |
| 683 ** searches the list. Neither the application code nor the VFS | |
| 684 ** implementation should use the pNext pointer. | |
| 685 ** | |
| 686 ** The pNext field is the only field in the sqlite3_vfs | |
| 687 ** structure that SQLite will ever modify. SQLite will only access | |
| 688 ** or modify this field while holding a particular static mutex. | |
| 689 ** The application should never modify anything within the sqlite3_vfs | |
| 690 ** object once the object has been registered. | |
| 691 ** | |
| 692 ** The zName field holds the name of the VFS module. The name must | |
| 693 ** be unique across all VFS modules. | |
| 694 ** | |
| 695 ** SQLite will guarantee that the zFilename parameter to xOpen | |
| 696 ** is either a NULL pointer or string obtained | |
| 697 ** from xFullPathname(). SQLite further guarantees that | |
| 698 ** the string will be valid and unchanged until xClose() is | |
| 699 ** called. Because of the previous sentence, | |
| 700 ** the [sqlite3_file] can safely store a pointer to the | |
| 701 ** filename if it needs to remember the filename for some reason. | |
| 702 ** If the zFilename parameter is xOpen is a NULL pointer then xOpen | |
| 703 ** must invent its own temporary name for the file. Whenever the | |
| 704 ** xFilename parameter is NULL it will also be the case that the | |
| 705 ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. | |
| 706 ** | |
| 707 ** The flags argument to xOpen() includes all bits set in | |
| 708 ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] | |
| 709 ** or [sqlite3_open16()] is used, then flags includes at least | |
| 710 ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. | |
| 711 ** If xOpen() opens a file read-only then it sets *pOutFlags to | |
| 712 ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. | |
| 713 ** | |
| 714 ** SQLite will also add one of the following flags to the xOpen() | |
| 715 ** call, depending on the object being opened: | |
| 716 ** | |
| 717 ** <ul> | |
| 718 ** <li> [SQLITE_OPEN_MAIN_DB] | |
| 719 ** <li> [SQLITE_OPEN_MAIN_JOURNAL] | |
| 720 ** <li> [SQLITE_OPEN_TEMP_DB] | |
| 721 ** <li> [SQLITE_OPEN_TEMP_JOURNAL] | |
| 722 ** <li> [SQLITE_OPEN_TRANSIENT_DB] | |
| 723 ** <li> [SQLITE_OPEN_SUBJOURNAL] | |
| 724 ** <li> [SQLITE_OPEN_MASTER_JOURNAL] | |
| 725 ** </ul> | |
| 726 ** | |
| 727 ** The file I/O implementation can use the object type flags to | |
| 728 ** change the way it deals with files. For example, an application | |
| 729 ** that does not care about crash recovery or rollback might make | |
| 730 ** the open of a journal file a no-op. Writes to this journal would | |
| 731 ** also be no-ops, and any attempt to read the journal would return | |
| 732 ** SQLITE_IOERR. Or the implementation might recognize that a database | |
| 733 ** file will be doing page-aligned sector reads and writes in a random | |
| 734 ** order and set up its I/O subsystem accordingly. | |
| 735 ** | |
| 736 ** SQLite might also add one of the following flags to the xOpen method: | |
| 737 ** | |
| 738 ** <ul> | |
| 739 ** <li> [SQLITE_OPEN_DELETEONCLOSE] | |
| 740 ** <li> [SQLITE_OPEN_EXCLUSIVE] | |
| 741 ** </ul> | |
| 742 ** | |
| 743 ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be | |
| 744 ** deleted when it is closed. The [SQLITE_OPEN_DELETEONCLOSE] | |
| 745 ** will be set for TEMP databases, journals and for subjournals. | |
| 746 ** | |
| 747 ** The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction | |
| 748 ** with the [SQLITE_OPEN_CREATE] flag, which are both directly | |
| 749 ** analogous to the O_EXCL and O_CREAT flags of the POSIX open() | |
| 750 ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the | |
| 751 ** SQLITE_OPEN_CREATE, is used to indicate that file should always | |
| 752 ** be created, and that it is an error if it already exists. | |
| 753 ** It is <i>not</i> used to indicate the file should be opened | |
| 754 ** for exclusive access. | |
| 755 ** | |
| 756 ** At least szOsFile bytes of memory are allocated by SQLite | |
| 757 ** to hold the [sqlite3_file] structure passed as the third | |
| 758 ** argument to xOpen. The xOpen method does not have to | |
| 759 ** allocate the structure; it should just fill it in. Note that | |
| 760 ** the xOpen method must set the sqlite3_file.pMethods to either | |
| 761 ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do | |
| 762 ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods | |
| 763 ** element will be valid after xOpen returns regardless of the success | |
| 764 ** or failure of the xOpen call. | |
| 765 ** | |
| 766 ** The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] | |
| 767 ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to | |
| 768 ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] | |
| 769 ** to test whether a file is at least readable. The file can be a | |
| 770 ** directory. | |
| 771 ** | |
| 772 ** SQLite will always allocate at least mxPathname+1 bytes for the | |
| 773 ** output buffer xFullPathname. The exact size of the output buffer | |
| 774 ** is also passed as a parameter to both methods. If the output buffer | |
| 775 ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is | |
| 776 ** handled as a fatal error by SQLite, vfs implementations should endeavor | |
| 777 ** to prevent this by setting mxPathname to a sufficiently large value. | |
| 778 ** | |
| 779 ** The xRandomness(), xSleep(), and xCurrentTime() interfaces | |
| 780 ** are not strictly a part of the filesystem, but they are | |
| 781 ** included in the VFS structure for completeness. | |
| 782 ** The xRandomness() function attempts to return nBytes bytes | |
| 783 ** of good-quality randomness into zOut. The return value is | |
| 784 ** the actual number of bytes of randomness obtained. | |
| 785 ** The xSleep() method causes the calling thread to sleep for at | |
| 786 ** least the number of microseconds given. The xCurrentTime() | |
| 787 ** method returns a Julian Day Number for the current date and time. | |
| 788 ** | |
| 789 */ | |
| 790 typedef struct sqlite3_vfs sqlite3_vfs; | |
| 791 struct sqlite3_vfs { | |
| 792 int iVersion; /* Structure version number */ | |
| 793 int szOsFile; /* Size of subclassed sqlite3_file */ | |
| 794 int mxPathname; /* Maximum file pathname length */ | |
| 795 sqlite3_vfs *pNext; /* Next registered VFS */ | |
| 796 const char *zName; /* Name of this virtual file system */ | |
| 797 void *pAppData; /* Pointer to application-specific data */ | |
| 798 int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*, | |
| 799 int flags, int *pOutFlags); | |
| 800 int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); | |
| 801 int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); | |
| 802 int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); | |
| 803 void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); | |
| 804 void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); | |
| 805 void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void); | |
| 806 void (*xDlClose)(sqlite3_vfs*, void*); | |
| 807 int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); | |
| 808 int (*xSleep)(sqlite3_vfs*, int microseconds); | |
| 809 int (*xCurrentTime)(sqlite3_vfs*, double*); | |
| 810 int (*xGetLastError)(sqlite3_vfs*, int, char *); | |
| 811 /* New fields may be appended in figure versions. The iVersion | |
| 812 ** value will increment whenever this happens. */ | |
| 813 }; | |
| 814 | |
| 815 /* | |
| 816 ** CAPI3REF: Flags for the xAccess VFS method {H11190} <H11140> | |
| 817 ** | |
| 818 ** These integer constants can be used as the third parameter to | |
| 819 ** the xAccess method of an [sqlite3_vfs] object. {END} They determine | |
| 820 ** what kind of permissions the xAccess method is looking for. | |
| 821 ** With SQLITE_ACCESS_EXISTS, the xAccess method | |
| 822 ** simply checks whether the file exists. | |
| 823 ** With SQLITE_ACCESS_READWRITE, the xAccess method | |
| 824 ** checks whether the file is both readable and writable. | |
| 825 ** With SQLITE_ACCESS_READ, the xAccess method | |
| 826 ** checks whether the file is readable. | |
| 827 */ | |
| 828 #define SQLITE_ACCESS_EXISTS 0 | |
| 829 #define SQLITE_ACCESS_READWRITE 1 | |
| 830 #define SQLITE_ACCESS_READ 2 | |
| 831 | |
| 832 /* | |
| 833 ** CAPI3REF: Initialize The SQLite Library {H10130} <S20000><S30100> | |
| 834 ** | |
| 835 ** The sqlite3_initialize() routine initializes the | |
| 836 ** SQLite library. The sqlite3_shutdown() routine | |
| 837 ** deallocates any resources that were allocated by sqlite3_initialize(). | |
| 838 ** | |
| 839 ** A call to sqlite3_initialize() is an "effective" call if it is | |
| 840 ** the first time sqlite3_initialize() is invoked during the lifetime of | |
| 841 ** the process, or if it is the first time sqlite3_initialize() is invoked | |
| 842 ** following a call to sqlite3_shutdown(). Only an effective call | |
| 843 ** of sqlite3_initialize() does any initialization. All other calls | |
| 844 ** are harmless no-ops. | |
| 845 ** | |
| 846 ** A call to sqlite3_shutdown() is an "effective" call if it is the first | |
| 847 ** call to sqlite3_shutdown() since the last sqlite3_initialize(). Only | |
| 848 ** an effective call to sqlite3_shutdown() does any deinitialization. | |
| 849 ** All other calls to sqlite3_shutdown() are harmless no-ops. | |
| 850 ** | |
| 851 ** Among other things, sqlite3_initialize() shall invoke | |
| 852 ** sqlite3_os_init(). Similarly, sqlite3_shutdown() | |
| 853 ** shall invoke sqlite3_os_end(). | |
| 854 ** | |
| 855 ** The sqlite3_initialize() routine returns [SQLITE_OK] on success. | |
| 856 ** If for some reason, sqlite3_initialize() is unable to initialize | |
| 857 ** the library (perhaps it is unable to allocate a needed resource such | |
| 858 ** as a mutex) it returns an [error code] other than [SQLITE_OK]. | |
| 859 ** | |
| 860 ** The sqlite3_initialize() routine is called internally by many other | |
| 861 ** SQLite interfaces so that an application usually does not need to | |
| 862 ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] | |
| 863 ** calls sqlite3_initialize() so the SQLite library will be automatically | |
| 864 ** initialized when [sqlite3_open()] is called if it has not be initialized | |
| 865 ** already. However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT] | |
| 866 ** compile-time option, then the automatic calls to sqlite3_initialize() | |
| 867 ** are omitted and the application must call sqlite3_initialize() directly | |
| 868 ** prior to using any other SQLite interface. For maximum portability, | |
| 869 ** it is recommended that applications always invoke sqlite3_initialize() | |
| 870 ** directly prior to using any other SQLite interface. Future releases | |
| 871 ** of SQLite may require this. In other words, the behavior exhibited | |
| 872 ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the | |
| 873 ** default behavior in some future release of SQLite. | |
| 874 ** | |
| 875 ** The sqlite3_os_init() routine does operating-system specific | |
| 876 ** initialization of the SQLite library. The sqlite3_os_end() | |
| 877 ** routine undoes the effect of sqlite3_os_init(). Typical tasks | |
| 878 ** performed by these routines include allocation or deallocation | |
| 879 ** of static resources, initialization of global variables, | |
| 880 ** setting up a default [sqlite3_vfs] module, or setting up | |
| 881 ** a default configuration using [sqlite3_config()]. | |
| 882 ** | |
| 883 ** The application should never invoke either sqlite3_os_init() | |
| 884 ** or sqlite3_os_end() directly. The application should only invoke | |
| 885 ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() | |
| 886 ** interface is called automatically by sqlite3_initialize() and | |
| 887 ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate | |
| 888 ** implementations for sqlite3_os_init() and sqlite3_os_end() | |
| 889 ** are built into SQLite when it is compiled for Unix, Windows, or OS/2. | |
| 890 ** When [custom builds | built for other platforms] | |
| 891 ** (using the [SQLITE_OS_OTHER=1] compile-time | |
| 892 ** option) the application must supply a suitable implementation for | |
| 893 ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied | |
| 894 ** implementation of sqlite3_os_init() or sqlite3_os_end() | |
| 895 ** must return [SQLITE_OK] on success and some other [error code] upon | |
| 896 ** failure. | |
| 897 */ | |
| 898 SQLITE_API int sqlite3_initialize(void); | |
| 899 SQLITE_API int sqlite3_shutdown(void); | |
| 900 SQLITE_API int sqlite3_os_init(void); | |
| 901 SQLITE_API int sqlite3_os_end(void); | |
| 902 | |
| 903 /* | |
| 904 ** CAPI3REF: Configuring The SQLite Library {H14100} <S20000><S30200> | |
| 905 ** EXPERIMENTAL | |
| 906 ** | |
| 907 ** The sqlite3_config() interface is used to make global configuration | |
| 908 ** changes to SQLite in order to tune SQLite to the specific needs of | |
| 909 ** the application. The default configuration is recommended for most | |
| 910 ** applications and so this routine is usually not necessary. It is | |
| 911 ** provided to support rare applications with unusual needs. | |
| 912 ** | |
| 913 ** The sqlite3_config() interface is not threadsafe. The application | |
| 914 ** must insure that no other SQLite interfaces are invoked by other | |
| 915 ** threads while sqlite3_config() is running. Furthermore, sqlite3_config() | |
| 916 ** may only be invoked prior to library initialization using | |
| 917 ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. | |
| 918 ** Note, however, that sqlite3_config() can be called as part of the | |
| 919 ** implementation of an application-defined [sqlite3_os_init()]. | |
| 920 ** | |
| 921 ** The first argument to sqlite3_config() is an integer | |
| 922 ** [SQLITE_CONFIG_SINGLETHREAD | configuration option] that determines | |
| 923 ** what property of SQLite is to be configured. Subsequent arguments | |
| 924 ** vary depending on the [SQLITE_CONFIG_SINGLETHREAD | configuration option] | |
| 925 ** in the first argument. | |
| 926 ** | |
| 927 ** When a configuration option is set, sqlite3_config() returns [SQLITE_OK]. | |
| 928 ** If the option is unknown or SQLite is unable to set the option | |
| 929 ** then this routine returns a non-zero [error code]. | |
| 930 ** | |
| 931 ** Requirements: | |
| 932 ** [H14103] [H14106] [H14120] [H14123] [H14126] [H14129] [H14132] [H14135] | |
| 933 ** [H14138] [H14141] [H14144] [H14147] [H14150] [H14153] [H14156] [H14159] | |
| 934 ** [H14162] [H14165] [H14168] | |
| 935 */ | |
| 936 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_config(int, ...); | |
| 937 | |
| 938 /* | |
| 939 ** CAPI3REF: Configure database connections {H14200} <S20000> | |
| 940 ** EXPERIMENTAL | |
| 941 ** | |
| 942 ** The sqlite3_db_config() interface is used to make configuration | |
| 943 ** changes to a [database connection]. The interface is similar to | |
| 944 ** [sqlite3_config()] except that the changes apply to a single | |
| 945 ** [database connection] (specified in the first argument). The | |
| 946 ** sqlite3_db_config() interface can only be used immediately after | |
| 947 ** the database connection is created using [sqlite3_open()], | |
| 948 ** [sqlite3_open16()], or [sqlite3_open_v2()]. | |
| 949 ** | |
| 950 ** The second argument to sqlite3_db_config(D,V,...) is the | |
| 951 ** configuration verb - an integer code that indicates what | |
| 952 ** aspect of the [database connection] is being configured. | |
| 953 ** The only choice for this value is [SQLITE_DBCONFIG_LOOKASIDE]. | |
| 954 ** New verbs are likely to be added in future releases of SQLite. | |
| 955 ** Additional arguments depend on the verb. | |
| 956 ** | |
| 957 ** Requirements: | |
| 958 ** [H14203] [H14206] [H14209] [H14212] [H14215] | |
| 959 */ | |
| 960 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_db_config(sqlite3*, int op, ...); | |
| 961 | |
| 962 /* | |
| 963 ** CAPI3REF: Memory Allocation Routines {H10155} <S20120> | |
| 964 ** EXPERIMENTAL | |
| 965 ** | |
| 966 ** An instance of this object defines the interface between SQLite | |
| 967 ** and low-level memory allocation routines. | |
| 968 ** | |
| 969 ** This object is used in only one place in the SQLite interface. | |
| 970 ** A pointer to an instance of this object is the argument to | |
| 971 ** [sqlite3_config()] when the configuration option is | |
| 972 ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC]. | |
| 973 ** By creating an instance of this object | |
| 974 ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC]) | |
| 975 ** during configuration, an application can specify an alternative | |
| 976 ** memory allocation subsystem for SQLite to use for all of its | |
| 977 ** dynamic memory needs. | |
| 978 ** | |
| 979 ** Note that SQLite comes with several [built-in memory allocators] | |
| 980 ** that are perfectly adequate for the overwhelming majority of applications | |
| 981 ** and that this object is only useful to a tiny minority of applications | |
| 982 ** with specialized memory allocation requirements. This object is | |
| 983 ** also used during testing of SQLite in order to specify an alternative | |
| 984 ** memory allocator that simulates memory out-of-memory conditions in | |
| 985 ** order to verify that SQLite recovers gracefully from such | |
| 986 ** conditions. | |
| 987 ** | |
| 988 ** The xMalloc and xFree methods must work like the | |
| 989 ** malloc() and free() functions from the standard C library. | |
| 990 ** The xRealloc method must work like realloc() from the standard C library | |
| 991 ** with the exception that if the second argument to xRealloc is zero, | |
| 992 ** xRealloc must be a no-op - it must not perform any allocation or | |
| 993 ** deallocation. SQLite guaranteeds that the second argument to | |
| 994 ** xRealloc is always a value returned by a prior call to xRoundup. | |
| 995 ** And so in cases where xRoundup always returns a positive number, | |
| 996 ** xRealloc can perform exactly as the standard library realloc() and | |
| 997 ** still be in compliance with this specification. | |
| 998 ** | |
| 999 ** xSize should return the allocated size of a memory allocation | |
| 1000 ** previously obtained from xMalloc or xRealloc. The allocated size | |
| 1001 ** is always at least as big as the requested size but may be larger. | |
| 1002 ** | |
| 1003 ** The xRoundup method returns what would be the allocated size of | |
| 1004 ** a memory allocation given a particular requested size. Most memory | |
| 1005 ** allocators round up memory allocations at least to the next multiple | |
| 1006 ** of 8. Some allocators round up to a larger multiple or to a power of 2. | |
| 1007 ** Every memory allocation request coming in through [sqlite3_malloc()] | |
| 1008 ** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0, | |
| 1009 ** that causes the corresponding memory allocation to fail. | |
| 1010 ** | |
| 1011 ** The xInit method initializes the memory allocator. (For example, | |
| 1012 ** it might allocate any require mutexes or initialize internal data | |
| 1013 ** structures. The xShutdown method is invoked (indirectly) by | |
| 1014 ** [sqlite3_shutdown()] and should deallocate any resources acquired | |
| 1015 ** by xInit. The pAppData pointer is used as the only parameter to | |
| 1016 ** xInit and xShutdown. | |
| 1017 ** | |
| 1018 ** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes | |
| 1019 ** the xInit method, so the xInit method need not be threadsafe. The | |
| 1020 ** xShutdown method is only called from [sqlite3_shutdown()] so it does | |
| 1021 ** not need to be threadsafe either. For all other methods, SQLite | |
| 1022 ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the | |
| 1023 ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which | |
| 1024 ** it is by default) and so the methods are automatically serialized. | |
| 1025 ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other | |
| 1026 ** methods must be threadsafe or else make their own arrangements for | |
| 1027 ** serialization. | |
| 1028 ** | |
| 1029 ** SQLite will never invoke xInit() more than once without an intervening | |
| 1030 ** call to xShutdown(). | |
| 1031 */ | |
| 1032 typedef struct sqlite3_mem_methods sqlite3_mem_methods; | |
| 1033 struct sqlite3_mem_methods { | |
| 1034 void *(*xMalloc)(int); /* Memory allocation function */ | |
| 1035 void (*xFree)(void*); /* Free a prior allocation */ | |
| 1036 void *(*xRealloc)(void*,int); /* Resize an allocation */ | |
| 1037 int (*xSize)(void*); /* Return the size of an allocation */ | |
| 1038 int (*xRoundup)(int); /* Round up request size to allocation size */ | |
| 1039 int (*xInit)(void*); /* Initialize the memory allocator */ | |
| 1040 void (*xShutdown)(void*); /* Deinitialize the memory allocator */ | |
| 1041 void *pAppData; /* Argument to xInit() and xShutdown() */ | |
| 1042 }; | |
| 1043 | |
| 1044 /* | |
| 1045 ** CAPI3REF: Configuration Options {H10160} <S20000> | |
| 1046 ** EXPERIMENTAL | |
| 1047 ** | |
| 1048 ** These constants are the available integer configuration options that | |
| 1049 ** can be passed as the first argument to the [sqlite3_config()] interface. | |
| 1050 ** | |
| 1051 ** New configuration options may be added in future releases of SQLite. | |
| 1052 ** Existing configuration options might be discontinued. Applications | |
| 1053 ** should check the return code from [sqlite3_config()] to make sure that | |
| 1054 ** the call worked. The [sqlite3_config()] interface will return a | |
| 1055 ** non-zero [error code] if a discontinued or unsupported configuration option | |
| 1056 ** is invoked. | |
| 1057 ** | |
| 1058 ** <dl> | |
| 1059 ** <dt>SQLITE_CONFIG_SINGLETHREAD</dt> | |
| 1060 ** <dd>There are no arguments to this option. This option disables | |
| 1061 ** all mutexing and puts SQLite into a mode where it can only be used | |
| 1062 ** by a single thread.</dd> | |
| 1063 ** | |
| 1064 ** <dt>SQLITE_CONFIG_MULTITHREAD</dt> | |
| 1065 ** <dd>There are no arguments to this option. This option disables | |
| 1066 ** mutexing on [database connection] and [prepared statement] objects. | |
| 1067 ** The application is responsible for serializing access to | |
| 1068 ** [database connections] and [prepared statements]. But other mutexes | |
| 1069 ** are enabled so that SQLite will be safe to use in a multi-threaded | |
| 1070 ** environment as long as no two threads attempt to use the same | |
| 1071 ** [database connection] at the same time. See the [threading mode] | |
| 1072 ** documentation for additional information.</dd> | |
| 1073 ** | |
| 1074 ** <dt>SQLITE_CONFIG_SERIALIZED</dt> | |
| 1075 ** <dd>There are no arguments to this option. This option enables | |
| 1076 ** all mutexes including the recursive | |
| 1077 ** mutexes on [database connection] and [prepared statement] objects. | |
| 1078 ** In this mode (which is the default when SQLite is compiled with | |
| 1079 ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access | |
| 1080 ** to [database connections] and [prepared statements] so that the | |
| 1081 ** application is free to use the same [database connection] or the | |
| 1082 ** same [prepared statement] in different threads at the same time. | |
| 1083 ** See the [threading mode] documentation for additional information.</dd> | |
| 1084 ** | |
| 1085 ** <dt>SQLITE_CONFIG_MALLOC</dt> | |
| 1086 ** <dd>This option takes a single argument which is a pointer to an | |
| 1087 ** instance of the [sqlite3_mem_methods] structure. The argument specifies | |
| 1088 ** alternative low-level memory allocation routines to be used in place of | |
| 1089 ** the memory allocation routines built into SQLite.</dd> | |
| 1090 ** | |
| 1091 ** <dt>SQLITE_CONFIG_GETMALLOC</dt> | |
| 1092 ** <dd>This option takes a single argument which is a pointer to an | |
| 1093 ** instance of the [sqlite3_mem_methods] structure. The [sqlite3_mem_methods] | |
| 1094 ** structure is filled with the currently defined memory allocation routines. | |
| 1095 ** This option can be used to overload the default memory allocation | |
| 1096 ** routines with a wrapper that simulations memory allocation failure or | |
| 1097 ** tracks memory usage, for example.</dd> | |
| 1098 ** | |
| 1099 ** <dt>SQLITE_CONFIG_MEMSTATUS</dt> | |
| 1100 ** <dd>This option takes single argument of type int, interpreted as a | |
| 1101 ** boolean, which enables or disables the collection of memory allocation | |
| 1102 ** statistics. When disabled, the following SQLite interfaces become | |
| 1103 ** non-operational: | |
| 1104 ** <ul> | |
| 1105 ** <li> [sqlite3_memory_used()] | |
| 1106 ** <li> [sqlite3_memory_highwater()] | |
| 1107 ** <li> [sqlite3_soft_heap_limit()] | |
| 1108 ** <li> [sqlite3_status()] | |
| 1109 ** </ul> | |
| 1110 ** </dd> | |
| 1111 ** | |
| 1112 ** <dt>SQLITE_CONFIG_SCRATCH</dt> | |
| 1113 ** <dd>This option specifies a static memory buffer that SQLite can use for | |
| 1114 ** scratch memory. There are three arguments: A pointer an 8-byte | |
| 1115 ** aligned memory buffer from which the scrach allocations will be | |
| 1116 ** drawn, the size of each scratch allocation (sz), | |
| 1117 ** and the maximum number of scratch allocations (N). The sz | |
| 1118 ** argument must be a multiple of 16. The sz parameter should be a few bytes | |
| 1119 ** larger than the actual scratch space required due to internal overhead. | |
| 1120 ** The first argument should pointer to an 8-byte aligned buffer | |
| 1121 ** of at least sz*N bytes of memory. | |
| 1122 ** SQLite will use no more than one scratch buffer at once per thread, so | |
| 1123 ** N should be set to the expected maximum number of threads. The sz | |
| 1124 ** parameter should be 6 times the size of the largest database page size. | |
| 1125 ** Scratch buffers are used as part of the btree balance operation. If | |
| 1126 ** The btree balancer needs additional memory beyond what is provided by | |
| 1127 ** scratch buffers or if no scratch buffer space is specified, then SQLite | |
| 1128 ** goes to [sqlite3_malloc()] to obtain the memory it needs.</dd> | |
| 1129 ** | |
| 1130 ** <dt>SQLITE_CONFIG_PAGECACHE</dt> | |
| 1131 ** <dd>This option specifies a static memory buffer that SQLite can use for | |
| 1132 ** the database page cache with the default page cache implemenation. | |
| 1133 ** This configuration should not be used if an application-define page | |
| 1134 ** cache implementation is loaded using the SQLITE_CONFIG_PCACHE option. | |
| 1135 ** There are three arguments to this option: A pointer to 8-byte aligned | |
| 1136 ** memory, the size of each page buffer (sz), and the number of pages (N). | |
| 1137 ** The sz argument should be the size of the largest database page | |
| 1138 ** (a power of two between 512 and 32768) plus a little extra for each | |
| 1139 ** page header. The page header size is 20 to 40 bytes depending on | |
| 1140 ** the host architecture. It is harmless, apart from the wasted memory, | |
| 1141 ** to make sz a little too large. The first | |
| 1142 ** argument should point to an allocation of at least sz*N bytes of memory. | |
| 1143 ** SQLite will use the memory provided by the first argument to satisfy its | |
| 1144 ** memory needs for the first N pages that it adds to cache. If additional | |
| 1145 ** page cache memory is needed beyond what is provided by this option, then | |
| 1146 ** SQLite goes to [sqlite3_malloc()] for the additional storage space. | |
| 1147 ** The implementation might use one or more of the N buffers to hold | |
| 1148 ** memory accounting information. The pointer in the first argument must | |
| 1149 ** be aligned to an 8-byte boundary or subsequent behavior of SQLite | |
| 1150 ** will be undefined.</dd> | |
| 1151 ** | |
| 1152 ** <dt>SQLITE_CONFIG_HEAP</dt> | |
| 1153 ** <dd>This option specifies a static memory buffer that SQLite will use | |
| 1154 ** for all of its dynamic memory allocation needs beyond those provided | |
| 1155 ** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE]. | |
| 1156 ** There are three arguments: An 8-byte aligned pointer to the memory, | |
| 1157 ** the number of bytes in the memory buffer, and the minimum allocation size. | |
| 1158 ** If the first pointer (the memory pointer) is NULL, then SQLite reverts | |
| 1159 ** to using its default memory allocator (the system malloc() implementation), | |
| 1160 ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. If the | |
| 1161 ** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or | |
| 1162 ** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory | |
| 1163 ** allocator is engaged to handle all of SQLites memory allocation needs. | |
| 1164 ** The first pointer (the memory pointer) must be aligned to an 8-byte | |
| 1165 ** boundary or subsequent behavior of SQLite will be undefined.</dd> | |
| 1166 ** | |
| 1167 ** <dt>SQLITE_CONFIG_MUTEX</dt> | |
| 1168 ** <dd>This option takes a single argument which is a pointer to an | |
| 1169 ** instance of the [sqlite3_mutex_methods] structure. The argument specifies | |
| 1170 ** alternative low-level mutex routines to be used in place | |
| 1171 ** the mutex routines built into SQLite.</dd> | |
| 1172 ** | |
| 1173 ** <dt>SQLITE_CONFIG_GETMUTEX</dt> | |
| 1174 ** <dd>This option takes a single argument which is a pointer to an | |
| 1175 ** instance of the [sqlite3_mutex_methods] structure. The | |
| 1176 ** [sqlite3_mutex_methods] | |
| 1177 ** structure is filled with the currently defined mutex routines. | |
| 1178 ** This option can be used to overload the default mutex allocation | |
| 1179 ** routines with a wrapper used to track mutex usage for performance | |
| 1180 ** profiling or testing, for example.</dd> | |
| 1181 ** | |
| 1182 ** <dt>SQLITE_CONFIG_LOOKASIDE</dt> | |
| 1183 ** <dd>This option takes two arguments that determine the default | |
| 1184 ** memory allocation lookaside optimization. The first argument is the | |
| 1185 ** size of each lookaside buffer slot and the second is the number of | |
| 1186 ** slots allocated to each database connection. This option sets the | |
| 1187 ** <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE] | |
| 1188 ** verb to [sqlite3_db_config()] can be used to change the lookaside | |
| 1189 ** configuration on individual connections.</dd> | |
| 1190 ** | |
| 1191 ** <dt>SQLITE_CONFIG_PCACHE</dt> | |
| 1192 ** <dd>This option takes a single argument which is a pointer to | |
| 1193 ** an [sqlite3_pcache_methods] object. This object specifies the interface | |
| 1194 ** to a custom page cache implementation. SQLite makes a copy of the | |
| 1195 ** object and uses it for page cache memory allocations.</dd> | |
| 1196 ** | |
| 1197 ** <dt>SQLITE_CONFIG_GETPCACHE</dt> | |
| 1198 ** <dd>This option takes a single argument which is a pointer to an | |
| 1199 ** [sqlite3_pcache_methods] object. SQLite copies of the current | |
| 1200 ** page cache implementation into that object.</dd> | |
| 1201 ** | |
| 1202 ** </dl> | |
| 1203 */ | |
| 1204 #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ | |
| 1205 #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ | |
| 1206 #define SQLITE_CONFIG_SERIALIZED 3 /* nil */ | |
| 1207 #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ | |
| 1208 #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ | |
| 1209 #define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */ | |
| 1210 #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ | |
| 1211 #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ | |
| 1212 #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ | |
| 1213 #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ | |
| 1214 #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ | |
| 1215 /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ | |
| 1216 #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ | |
| 1217 #define SQLITE_CONFIG_PCACHE 14 /* sqlite3_pcache_methods* */ | |
| 1218 #define SQLITE_CONFIG_GETPCACHE 15 /* sqlite3_pcache_methods* */ | |
| 1219 | |
| 1220 /* | |
| 1221 ** CAPI3REF: Configuration Options {H10170} <S20000> | |
| 1222 ** EXPERIMENTAL | |
| 1223 ** | |
| 1224 ** These constants are the available integer configuration options that | |
| 1225 ** can be passed as the second argument to the [sqlite3_db_config()] interface. | |
| 1226 ** | |
| 1227 ** New configuration options may be added in future releases of SQLite. | |
| 1228 ** Existing configuration options might be discontinued. Applications | |
| 1229 ** should check the return code from [sqlite3_db_config()] to make sure that | |
| 1230 ** the call worked. The [sqlite3_db_config()] interface will return a | |
| 1231 ** non-zero [error code] if a discontinued or unsupported configuration option | |
| 1232 ** is invoked. | |
| 1233 ** | |
| 1234 ** <dl> | |
| 1235 ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt> | |
| 1236 ** <dd>This option takes three additional arguments that determine the | |
| 1237 ** [lookaside memory allocator] configuration for the [database connection]. | |
| 1238 ** The first argument (the third parameter to [sqlite3_db_config()] is a | |
| 1239 ** pointer to an memory buffer to use for lookaside memory. | |
| 1240 ** The first argument may be NULL in which case SQLite will allocate the | |
| 1241 ** lookaside buffer itself using [sqlite3_malloc()]. The second argument is the | |
| 1242 ** size of each lookaside buffer slot and the third argument is the number of | |
| 1243 ** slots. The size of the buffer in the first argument must be greater than | |
| 1244 ** or equal to the product of the second and third arguments. The buffer | |
| 1245 ** must be aligned to an 8-byte boundary. If the second argument is not | |
| 1246 ** a multiple of 8, it is internally rounded down to the next smaller | |
| 1247 ** multiple of 8. See also: [SQLITE_CONFIG_LOOKASIDE]</dd> | |
| 1248 ** | |
| 1249 ** </dl> | |
| 1250 */ | |
| 1251 #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ | |
| 1252 | |
| 1253 | |
| 1254 /* | |
| 1255 ** CAPI3REF: Enable Or Disable Extended Result Codes {H12200} <S10700> | |
| 1256 ** | |
| 1257 ** The sqlite3_extended_result_codes() routine enables or disables the | |
| 1258 ** [extended result codes] feature of SQLite. The extended result | |
| 1259 ** codes are disabled by default for historical compatibility considerations. | |
| 1260 ** | |
| 1261 ** Requirements: | |
| 1262 ** [H12201] [H12202] | |
| 1263 */ | |
| 1264 SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff); | |
| 1265 | |
| 1266 /* | |
| 1267 ** CAPI3REF: Last Insert Rowid {H12220} <S10700> | |
| 1268 ** | |
| 1269 ** Each entry in an SQLite table has a unique 64-bit signed | |
| 1270 ** integer key called the [ROWID | "rowid"]. The rowid is always available | |
| 1271 ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those | |
| 1272 ** names are not also used by explicitly declared columns. If | |
| 1273 ** the table has a column of type [INTEGER PRIMARY KEY] then that column | |
| 1274 ** is another alias for the rowid. | |
| 1275 ** | |
| 1276 ** This routine returns the [rowid] of the most recent | |
| 1277 ** successful [INSERT] into the database from the [database connection] | |
| 1278 ** in the first argument. If no successful [INSERT]s | |
| 1279 ** have ever occurred on that database connection, zero is returned. | |
| 1280 ** | |
| 1281 ** If an [INSERT] occurs within a trigger, then the [rowid] of the inserted | |
| 1282 ** row is returned by this routine as long as the trigger is running. | |
| 1283 ** But once the trigger terminates, the value returned by this routine | |
| 1284 ** reverts to the last value inserted before the trigger fired. | |
| 1285 ** | |
| 1286 ** An [INSERT] that fails due to a constraint violation is not a | |
| 1287 ** successful [INSERT] and does not change the value returned by this | |
| 1288 ** routine. Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, | |
| 1289 ** and INSERT OR ABORT make no changes to the return value of this | |
| 1290 ** routine when their insertion fails. When INSERT OR REPLACE | |
| 1291 ** encounters a constraint violation, it does not fail. The | |
| 1292 ** INSERT continues to completion after deleting rows that caused | |
| 1293 ** the constraint problem so INSERT OR REPLACE will always change | |
| 1294 ** the return value of this interface. | |
| 1295 ** | |
| 1296 ** For the purposes of this routine, an [INSERT] is considered to | |
| 1297 ** be successful even if it is subsequently rolled back. | |
| 1298 ** | |
| 1299 ** Requirements: | |
| 1300 ** [H12221] [H12223] | |
| 1301 ** | |
| 1302 ** If a separate thread performs a new [INSERT] on the same | |
| 1303 ** database connection while the [sqlite3_last_insert_rowid()] | |
| 1304 ** function is running and thus changes the last insert [rowid], | |
| 1305 ** then the value returned by [sqlite3_last_insert_rowid()] is | |
| 1306 ** unpredictable and might not equal either the old or the new | |
| 1307 ** last insert [rowid]. | |
| 1308 */ | |
| 1309 SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); | |
| 1310 | |
| 1311 /* | |
| 1312 ** CAPI3REF: Count The Number Of Rows Modified {H12240} <S10600> | |
| 1313 ** | |
| 1314 ** This function returns the number of database rows that were changed | |
| 1315 ** or inserted or deleted by the most recently completed SQL statement | |
| 1316 ** on the [database connection] specified by the first parameter. | |
| 1317 ** Only changes that are directly specified by the [INSERT], [UPDATE], | |
| 1318 ** or [DELETE] statement are counted. Auxiliary changes caused by | |
| 1319 ** triggers are not counted. Use the [sqlite3_total_changes()] function | |
| 1320 ** to find the total number of changes including changes caused by triggers. | |
| 1321 ** | |
| 1322 ** Changes to a view that are simulated by an [INSTEAD OF trigger] | |
| 1323 ** are not counted. Only real table changes are counted. | |
| 1324 ** | |
| 1325 ** A "row change" is a change to a single row of a single table | |
| 1326 ** caused by an INSERT, DELETE, or UPDATE statement. Rows that | |
| 1327 ** are changed as side effects of [REPLACE] constraint resolution, | |
| 1328 ** rollback, ABORT processing, [DROP TABLE], or by any other | |
| 1329 ** mechanisms do not count as direct row changes. | |
| 1330 ** | |
| 1331 ** A "trigger context" is a scope of execution that begins and | |
| 1332 ** ends with the script of a [CREATE TRIGGER | trigger]. | |
| 1333 ** Most SQL statements are | |
| 1334 ** evaluated outside of any trigger. This is the "top level" | |
| 1335 ** trigger context. If a trigger fires from the top level, a | |
| 1336 ** new trigger context is entered for the duration of that one | |
| 1337 ** trigger. Subtriggers create subcontexts for their duration. | |
| 1338 ** | |
| 1339 ** Calling [sqlite3_exec()] or [sqlite3_step()] recursively does | |
| 1340 ** not create a new trigger context. | |
| 1341 ** | |
| 1342 ** This function returns the number of direct row changes in the | |
| 1343 ** most recent INSERT, UPDATE, or DELETE statement within the same | |
| 1344 ** trigger context. | |
| 1345 ** | |
| 1346 ** Thus, when called from the top level, this function returns the | |
| 1347 ** number of changes in the most recent INSERT, UPDATE, or DELETE | |
| 1348 ** that also occurred at the top level. Within the body of a trigger, | |
| 1349 ** the sqlite3_changes() interface can be called to find the number of | |
| 1350 ** changes in the most recently completed INSERT, UPDATE, or DELETE | |
| 1351 ** statement within the body of the same trigger. | |
| 1352 ** However, the number returned does not include changes | |
| 1353 ** caused by subtriggers since those have their own context. | |
| 1354 ** | |
| 1355 ** See also the [sqlite3_total_changes()] interface and the | |
| 1356 ** [count_changes pragma]. | |
| 1357 ** | |
| 1358 ** Requirements: | |
| 1359 ** [H12241] [H12243] | |
| 1360 ** | |
| 1361 ** If a separate thread makes changes on the same database connection | |
| 1362 ** while [sqlite3_changes()] is running then the value returned | |
| 1363 ** is unpredictable and not meaningful. | |
| 1364 */ | |
| 1365 SQLITE_API int sqlite3_changes(sqlite3*); | |
| 1366 | |
| 1367 /* | |
| 1368 ** CAPI3REF: Total Number Of Rows Modified {H12260} <S10600> | |
| 1369 ** | |
| 1370 ** This function returns the number of row changes caused by [INSERT], | |
| 1371 ** [UPDATE] or [DELETE] statements since the [database connection] was opened. | |
| 1372 ** The count includes all changes from all | |
| 1373 ** [CREATE TRIGGER | trigger] contexts. However, | |
| 1374 ** the count does not include changes used to implement [REPLACE] constraints, | |
| 1375 ** do rollbacks or ABORT processing, or [DROP TABLE] processing. The | |
| 1376 ** count does not include rows of views that fire an [INSTEAD OF trigger], | |
| 1377 ** though if the INSTEAD OF trigger makes changes of its own, those changes | |
| 1378 ** are counted. | |
| 1379 ** The changes are counted as soon as the statement that makes them is | |
| 1380 ** completed (when the statement handle is passed to [sqlite3_reset()] or | |
| 1381 ** [sqlite3_finalize()]). | |
| 1382 ** | |
| 1383 ** See also the [sqlite3_changes()] interface and the | |
| 1384 ** [count_changes pragma]. | |
| 1385 ** | |
| 1386 ** Requirements: | |
| 1387 ** [H12261] [H12263] | |
| 1388 ** | |
| 1389 ** If a separate thread makes changes on the same database connection | |
| 1390 ** while [sqlite3_total_changes()] is running then the value | |
| 1391 ** returned is unpredictable and not meaningful. | |
| 1392 */ | |
| 1393 SQLITE_API int sqlite3_total_changes(sqlite3*); | |
| 1394 | |
| 1395 /* | |
| 1396 ** CAPI3REF: Interrupt A Long-Running Query {H12270} <S30500> | |
| 1397 ** | |
| 1398 ** This function causes any pending database operation to abort and | |
| 1399 ** return at its earliest opportunity. This routine is typically | |
| 1400 ** called in response to a user action such as pressing "Cancel" | |
| 1401 ** or Ctrl-C where the user wants a long query operation to halt | |
| 1402 ** immediately. | |
| 1403 ** | |
| 1404 ** It is safe to call this routine from a thread different from the | |
| 1405 ** thread that is currently running the database operation. But it | |
| 1406 ** is not safe to call this routine with a [database connection] that | |
| 1407 ** is closed or might close before sqlite3_interrupt() returns. | |
| 1408 ** | |
| 1409 ** If an SQL operation is very nearly finished at the time when | |
| 1410 ** sqlite3_interrupt() is called, then it might not have an opportunity | |
| 1411 ** to be interrupted and might continue to completion. | |
| 1412 ** | |
| 1413 ** An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. | |
| 1414 ** If the interrupted SQL operation is an INSERT, UPDATE, or DELETE | |
| 1415 ** that is inside an explicit transaction, then the entire transaction | |
| 1416 ** will be rolled back automatically. | |
| 1417 ** | |
| 1418 ** The sqlite3_interrupt(D) call is in effect until all currently running | |
| 1419 ** SQL statements on [database connection] D complete. Any new SQL statements | |
| 1420 ** that are started after the sqlite3_interrupt() call and before the | |
| 1421 ** running statements reaches zero are interrupted as if they had been | |
| 1422 ** running prior to the sqlite3_interrupt() call. New SQL statements | |
| 1423 ** that are started after the running statement count reaches zero are | |
| 1424 ** not effected by the sqlite3_interrupt(). | |
| 1425 ** A call to sqlite3_interrupt(D) that occurs when there are no running | |
| 1426 ** SQL statements is a no-op and has no effect on SQL statements | |
| 1427 ** that are started after the sqlite3_interrupt() call returns. | |
| 1428 ** | |
| 1429 ** Requirements: | |
| 1430 ** [H12271] [H12272] | |
| 1431 ** | |
| 1432 ** If the database connection closes while [sqlite3_interrupt()] | |
| 1433 ** is running then bad things will likely happen. | |
| 1434 */ | |
| 1435 SQLITE_API void sqlite3_interrupt(sqlite3*); | |
| 1436 | |
| 1437 /* | |
| 1438 ** CAPI3REF: Determine If An SQL Statement Is Complete {H10510} <S70200> | |
| 1439 ** | |
| 1440 ** These routines are useful during command-line input to determine if the | |
| 1441 ** currently entered text seems to form a complete SQL statement or | |
| 1442 ** if additional input is needed before sending the text into | |
| 1443 ** SQLite for parsing. These routines return 1 if the input string | |
| 1444 ** appears to be a complete SQL statement. A statement is judged to be | |
| 1445 ** complete if it ends with a semicolon token and is not a prefix of a | |
| 1446 ** well-formed CREATE TRIGGER statement. Semicolons that are embedded within | |
| 1447 ** string literals or quoted identifier names or comments are not | |
| 1448 ** independent tokens (they are part of the token in which they are | |
| 1449 ** embedded) and thus do not count as a statement terminator. Whitespace | |
| 1450 ** and comments that follow the final semicolon are ignored. | |
| 1451 ** | |
| 1452 ** These routines return 0 if the statement is incomplete. If a | |
| 1453 ** memory allocation fails, then SQLITE_NOMEM is returned. | |
| 1454 ** | |
| 1455 ** These routines do not parse the SQL statements thus | |
| 1456 ** will not detect syntactically incorrect SQL. | |
| 1457 ** | |
| 1458 ** If SQLite has not been initialized using [sqlite3_initialize()] prior | |
| 1459 ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked | |
| 1460 ** automatically by sqlite3_complete16(). If that initialization fails, | |
| 1461 ** then the return value from sqlite3_complete16() will be non-zero | |
| 1462 ** regardless of whether or not the input SQL is complete. | |
| 1463 ** | |
| 1464 ** Requirements: [H10511] [H10512] | |
| 1465 ** | |
| 1466 ** The input to [sqlite3_complete()] must be a zero-terminated | |
| 1467 ** UTF-8 string. | |
| 1468 ** | |
| 1469 ** The input to [sqlite3_complete16()] must be a zero-terminated | |
| 1470 ** UTF-16 string in native byte order. | |
| 1471 */ | |
| 1472 SQLITE_API int sqlite3_complete(const char *sql); | |
| 1473 SQLITE_API int sqlite3_complete16(const void *sql); | |
| 1474 | |
| 1475 /* | |
| 1476 ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors {H12310} <S40400> | |
| 1477 ** | |
| 1478 ** This routine sets a callback function that might be invoked whenever | |
| 1479 ** an attempt is made to open a database table that another thread | |
| 1480 ** or process has locked. | |
| 1481 ** | |
| 1482 ** If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] | |
| 1483 ** is returned immediately upon encountering the lock. If the busy callback | |
| 1484 ** is not NULL, then the callback will be invoked with two arguments. | |
| 1485 ** | |
| 1486 ** The first argument to the handler is a copy of the void* pointer which | |
| 1487 ** is the third argument to sqlite3_busy_handler(). The second argument to | |
| 1488 ** the handler callback is the number of times that the busy handler has | |
| 1489 ** been invoked for this locking event. If the | |
| 1490 ** busy callback returns 0, then no additional attempts are made to | |
| 1491 ** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned. | |
| 1492 ** If the callback returns non-zero, then another attempt | |
| 1493 ** is made to open the database for reading and the cycle repeats. | |
| 1494 ** | |
| 1495 ** The presence of a busy handler does not guarantee that it will be invoked | |
| 1496 ** when there is lock contention. If SQLite determines that invoking the busy | |
| 1497 ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] | |
| 1498 ** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler. | |
| 1499 ** Consider a scenario where one process is holding a read lock that | |
| 1500 ** it is trying to promote to a reserved lock and | |
| 1501 ** a second process is holding a reserved lock that it is trying | |
| 1502 ** to promote to an exclusive lock. The first process cannot proceed | |
| 1503 ** because it is blocked by the second and the second process cannot | |
| 1504 ** proceed because it is blocked by the first. If both processes | |
| 1505 ** invoke the busy handlers, neither will make any progress. Therefore, | |
| 1506 ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this | |
| 1507 ** will induce the first process to release its read lock and allow | |
| 1508 ** the second process to proceed. | |
| 1509 ** | |
| 1510 ** The default busy callback is NULL. | |
| 1511 ** | |
| 1512 ** The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED] | |
| 1513 ** when SQLite is in the middle of a large transaction where all the | |
| 1514 ** changes will not fit into the in-memory cache. SQLite will | |
| 1515 ** already hold a RESERVED lock on the database file, but it needs | |
| 1516 ** to promote this lock to EXCLUSIVE so that it can spill cache | |
| 1517 ** pages into the database file without harm to concurrent | |
| 1518 ** readers. If it is unable to promote the lock, then the in-memory | |
| 1519 ** cache will be left in an inconsistent state and so the error | |
| 1520 ** code is promoted from the relatively benign [SQLITE_BUSY] to | |
| 1521 ** the more severe [SQLITE_IOERR_BLOCKED]. This error code promotion | |
| 1522 ** forces an automatic rollback of the changes. See the | |
| 1523 ** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError"> | |
| 1524 ** CorruptionFollowingBusyError</a> wiki page for a discussion of why | |
| 1525 ** this is important. | |
| 1526 ** | |
| 1527 ** There can only be a single busy handler defined for each | |
| 1528 ** [database connection]. Setting a new busy handler clears any | |
| 1529 ** previously set handler. Note that calling [sqlite3_busy_timeout()] | |
| 1530 ** will also set or clear the busy handler. | |
| 1531 ** | |
| 1532 ** The busy callback should not take any actions which modify the | |
| 1533 ** database connection that invoked the busy handler. Any such actions | |
| 1534 ** result in undefined behavior. | |
| 1535 ** | |
| 1536 ** Requirements: | |
| 1537 ** [H12311] [H12312] [H12314] [H12316] [H12318] | |
| 1538 ** | |
| 1539 ** A busy handler must not close the database connection | |
| 1540 ** or [prepared statement] that invoked the busy handler. | |
| 1541 */ | |
| 1542 SQLITE_API int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*); | |
| 1543 | |
| 1544 /* | |
| 1545 ** CAPI3REF: Set A Busy Timeout {H12340} <S40410> | |
| 1546 ** | |
| 1547 ** This routine sets a [sqlite3_busy_handler | busy handler] that sleeps | |
| 1548 ** for a specified amount of time when a table is locked. The handler | |
| 1549 ** will sleep multiple times until at least "ms" milliseconds of sleeping | |
| 1550 ** have accumulated. {H12343} After "ms" milliseconds of sleeping, | |
| 1551 ** the handler returns 0 which causes [sqlite3_step()] to return | |
| 1552 ** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]. | |
| 1553 ** | |
| 1554 ** Calling this routine with an argument less than or equal to zero | |
| 1555 ** turns off all busy handlers. | |
| 1556 ** | |
| 1557 ** There can only be a single busy handler for a particular | |
| 1558 ** [database connection] any any given moment. If another busy handler | |
| 1559 ** was defined (using [sqlite3_busy_handler()]) prior to calling | |
| 1560 ** this routine, that other busy handler is cleared. | |
| 1561 ** | |
| 1562 ** Requirements: | |
| 1563 ** [H12341] [H12343] [H12344] | |
| 1564 */ | |
| 1565 SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms); | |
| 1566 | |
| 1567 /* | |
| 1568 ** CAPI3REF: Convenience Routines For Running Queries {H12370} <S10000> | |
| 1569 ** | |
| 1570 ** Definition: A <b>result table</b> is memory data structure created by the | |
| 1571 ** [sqlite3_get_table()] interface. A result table records the | |
| 1572 ** complete query results from one or more queries. | |
| 1573 ** | |
| 1574 ** The table conceptually has a number of rows and columns. But | |
| 1575 ** these numbers are not part of the result table itself. These | |
| 1576 ** numbers are obtained separately. Let N be the number of rows | |
| 1577 ** and M be the number of columns. | |
| 1578 ** | |
| 1579 ** A result table is an array of pointers to zero-terminated UTF-8 strings. | |
| 1580 ** There are (N+1)*M elements in the array. The first M pointers point | |
| 1581 ** to zero-terminated strings that contain the names of the columns. | |
| 1582 ** The remaining entries all point to query results. NULL values result | |
| 1583 ** in NULL pointers. All other values are in their UTF-8 zero-terminated | |
| 1584 ** string representation as returned by [sqlite3_column_text()]. | |
| 1585 ** | |
| 1586 ** A result table might consist of one or more memory allocations. | |
| 1587 ** It is not safe to pass a result table directly to [sqlite3_free()]. | |
| 1588 ** A result table should be deallocated using [sqlite3_free_table()]. | |
| 1589 ** | |
| 1590 ** As an example of the result table format, suppose a query result | |
| 1591 ** is as follows: | |
| 1592 ** | |
| 1593 ** <blockquote><pre> | |
| 1594 ** Name | Age | |
| 1595 ** ----------------------- | |
| 1596 ** Alice | 43 | |
| 1597 ** Bob | 28 | |
| 1598 ** Cindy | 21 | |
| 1599 ** </pre></blockquote> | |
| 1600 ** | |
| 1601 ** There are two column (M==2) and three rows (N==3). Thus the | |
| 1602 ** result table has 8 entries. Suppose the result table is stored | |
| 1603 ** in an array names azResult. Then azResult holds this content: | |
| 1604 ** | |
| 1605 ** <blockquote><pre> | |
| 1606 ** azResult[0] = "Name"; | |
| 1607 ** azResult[1] = "Age"; | |
| 1608 ** azResult[2] = "Alice"; | |
| 1609 ** azResult[3] = "43"; | |
| 1610 ** azResult[4] = "Bob"; | |
| 1611 ** azResult[5] = "28"; | |
| 1612 ** azResult[6] = "Cindy"; | |
| 1613 ** azResult[7] = "21"; | |
| 1614 ** </pre></blockquote> | |
| 1615 ** | |
| 1616 ** The sqlite3_get_table() function evaluates one or more | |
| 1617 ** semicolon-separated SQL statements in the zero-terminated UTF-8 | |
| 1618 ** string of its 2nd parameter. It returns a result table to the | |
| 1619 ** pointer given in its 3rd parameter. | |
| 1620 ** | |
| 1621 ** After the calling function has finished using the result, it should | |
| 1622 ** pass the pointer to the result table to sqlite3_free_table() in order to | |
| 1623 ** release the memory that was malloced. Because of the way the | |
| 1624 ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling | |
| 1625 ** function must not try to call [sqlite3_free()] directly. Only | |
| 1626 ** [sqlite3_free_table()] is able to release the memory properly and safely. | |
| 1627 ** | |
| 1628 ** The sqlite3_get_table() interface is implemented as a wrapper around | |
| 1629 ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access | |
| 1630 ** to any internal data structures of SQLite. It uses only the public | |
| 1631 ** interface defined here. As a consequence, errors that occur in the | |
| 1632 ** wrapper layer outside of the internal [sqlite3_exec()] call are not | |
| 1633 ** reflected in subsequent calls to [sqlite3_errcode()] or [sqlite3_errmsg()]. | |
| 1634 ** | |
| 1635 ** Requirements: | |
| 1636 ** [H12371] [H12373] [H12374] [H12376] [H12379] [H12382] | |
| 1637 */ | |
| 1638 SQLITE_API int sqlite3_get_table( | |
| 1639 sqlite3 *db, /* An open database */ | |
| 1640 const char *zSql, /* SQL to be evaluated */ | |
| 1641 char ***pazResult, /* Results of the query */ | |
| 1642 int *pnRow, /* Number of result rows written here */ | |
| 1643 int *pnColumn, /* Number of result columns written here */ | |
| 1644 char **pzErrmsg /* Error msg written here */ | |
| 1645 ); | |
| 1646 SQLITE_API void sqlite3_free_table(char **result); | |
| 1647 | |
| 1648 /* | |
| 1649 ** CAPI3REF: Formatted String Printing Functions {H17400} <S70000><S20000> | |
| 1650 ** | |
| 1651 ** These routines are work-alikes of the "printf()" family of functions | |
| 1652 ** from the standard C library. | |
| 1653 ** | |
| 1654 ** The sqlite3_mprintf() and sqlite3_vmprintf() routines write their | |
| 1655 ** results into memory obtained from [sqlite3_malloc()]. | |
| 1656 ** The strings returned by these two routines should be | |
| 1657 ** released by [sqlite3_free()]. Both routines return a | |
| 1658 ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough | |
| 1659 ** memory to hold the resulting string. | |
| 1660 ** | |
| 1661 ** In sqlite3_snprintf() routine is similar to "snprintf()" from | |
| 1662 ** the standard C library. The result is written into the | |
| 1663 ** buffer supplied as the second parameter whose size is given by | |
| 1664 ** the first parameter. Note that the order of the | |
| 1665 ** first two parameters is reversed from snprintf(). This is an | |
| 1666 ** historical accident that cannot be fixed without breaking | |
| 1667 ** backwards compatibility. Note also that sqlite3_snprintf() | |
| 1668 ** returns a pointer to its buffer instead of the number of | |
| 1669 ** characters actually written into the buffer. We admit that | |
| 1670 ** the number of characters written would be a more useful return | |
| 1671 ** value but we cannot change the implementation of sqlite3_snprintf() | |
| 1672 ** now without breaking compatibility. | |
| 1673 ** | |
| 1674 ** As long as the buffer size is greater than zero, sqlite3_snprintf() | |
| 1675 ** guarantees that the buffer is always zero-terminated. The first | |
| 1676 ** parameter "n" is the total size of the buffer, including space for | |
| 1677 ** the zero terminator. So the longest string that can be completely | |
| 1678 ** written will be n-1 characters. | |
| 1679 ** | |
| 1680 ** These routines all implement some additional formatting | |
| 1681 ** options that are useful for constructing SQL statements. | |
| 1682 ** All of the usual printf() formatting options apply. In addition, there | |
| 1683 ** is are "%q", "%Q", and "%z" options. | |
| 1684 ** | |
| 1685 ** The %q option works like %s in that it substitutes a null-terminated | |
| 1686 ** string from the argument list. But %q also doubles every '\'' character. | |
| 1687 ** %q is designed for use inside a string literal. By doubling each '\'' | |
| 1688 ** character it escapes that character and allows it to be inserted into | |
| 1689 ** the string. | |
| 1690 ** | |
| 1691 ** For example, assume the string variable zText contains text as follows: | |
| 1692 ** | |
| 1693 ** <blockquote><pre> | |
| 1694 ** char *zText = "It's a happy day!"; | |
| 1695 ** </pre></blockquote> | |
| 1696 ** | |
| 1697 ** One can use this text in an SQL statement as follows: | |
| 1698 ** | |
| 1699 ** <blockquote><pre> | |
| 1700 ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText); | |
| 1701 ** sqlite3_exec(db, zSQL, 0, 0, 0); | |
| 1702 ** sqlite3_free(zSQL); | |
| 1703 ** </pre></blockquote> | |
| 1704 ** | |
| 1705 ** Because the %q format string is used, the '\'' character in zText | |
| 1706 ** is escaped and the SQL generated is as follows: | |
| 1707 ** | |
| 1708 ** <blockquote><pre> | |
| 1709 ** INSERT INTO table1 VALUES('It''s a happy day!') | |
| 1710 ** </pre></blockquote> | |
| 1711 ** | |
| 1712 ** This is correct. Had we used %s instead of %q, the generated SQL | |
| 1713 ** would have looked like this: | |
| 1714 ** | |
| 1715 ** <blockquote><pre> | |
| 1716 ** INSERT INTO table1 VALUES('It's a happy day!'); | |
| 1717 ** </pre></blockquote> | |
| 1718 ** | |
| 1719 ** This second example is an SQL syntax error. As a general rule you should | |
| 1720 ** always use %q instead of %s when inserting text into a string literal. | |
| 1721 ** | |
| 1722 ** The %Q option works like %q except it also adds single quotes around | |
| 1723 ** the outside of the total string. Additionally, if the parameter in the | |
| 1724 ** argument list is a NULL pointer, %Q substitutes the text "NULL" (without | |
| 1725 ** single quotes) in place of the %Q option. So, for example, one could say: | |
| 1726 ** | |
| 1727 ** <blockquote><pre> | |
| 1728 ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText); | |
| 1729 ** sqlite3_exec(db, zSQL, 0, 0, 0); | |
| 1730 ** sqlite3_free(zSQL); | |
| 1731 ** </pre></blockquote> | |
| 1732 ** | |
| 1733 ** The code above will render a correct SQL statement in the zSQL | |
| 1734 ** variable even if the zText variable is a NULL pointer. | |
| 1735 ** | |
| 1736 ** The "%z" formatting option works exactly like "%s" with the | |
| 1737 ** addition that after the string has been read and copied into | |
| 1738 ** the result, [sqlite3_free()] is called on the input string. {END} | |
| 1739 ** | |
| 1740 ** Requirements: | |
| 1741 ** [H17403] [H17406] [H17407] | |
| 1742 */ | |
| 1743 SQLITE_API char *sqlite3_mprintf(const char*,...); | |
| 1744 SQLITE_API char *sqlite3_vmprintf(const char*, va_list); | |
| 1745 SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...); | |
| 1746 | |
| 1747 /* | |
| 1748 ** CAPI3REF: Memory Allocation Subsystem {H17300} <S20000> | |
| 1749 ** | |
| 1750 ** The SQLite core uses these three routines for all of its own | |
| 1751 ** internal memory allocation needs. "Core" in the previous sentence | |
| 1752 ** does not include operating-system specific VFS implementation. The | |
| 1753 ** Windows VFS uses native malloc() and free() for some operations. | |
| 1754 ** | |
| 1755 ** The sqlite3_malloc() routine returns a pointer to a block | |
| 1756 ** of memory at least N bytes in length, where N is the parameter. | |
| 1757 ** If sqlite3_malloc() is unable to obtain sufficient free | |
| 1758 ** memory, it returns a NULL pointer. If the parameter N to | |
| 1759 ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns | |
| 1760 ** a NULL pointer. | |
| 1761 ** | |
| 1762 ** Calling sqlite3_free() with a pointer previously returned | |
| 1763 ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so | |
| 1764 ** that it might be reused. The sqlite3_free() routine is | |
| 1765 ** a no-op if is called with a NULL pointer. Passing a NULL pointer | |
| 1766 ** to sqlite3_free() is harmless. After being freed, memory | |
| 1767 ** should neither be read nor written. Even reading previously freed | |
| 1768 ** memory might result in a segmentation fault or other severe error. | |
| 1769 ** Memory corruption, a segmentation fault, or other severe error | |
| 1770 ** might result if sqlite3_free() is called with a non-NULL pointer that | |
| 1771 ** was not obtained from sqlite3_malloc() or sqlite3_realloc(). | |
| 1772 ** | |
| 1773 ** The sqlite3_realloc() interface attempts to resize a | |
| 1774 ** prior memory allocation to be at least N bytes, where N is the | |
| 1775 ** second parameter. The memory allocation to be resized is the first | |
| 1776 ** parameter. If the first parameter to sqlite3_realloc() | |
| 1777 ** is a NULL pointer then its behavior is identical to calling | |
| 1778 ** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc(). | |
| 1779 ** If the second parameter to sqlite3_realloc() is zero or | |
| 1780 ** negative then the behavior is exactly the same as calling | |
| 1781 ** sqlite3_free(P) where P is the first parameter to sqlite3_realloc(). | |
| 1782 ** sqlite3_realloc() returns a pointer to a memory allocation | |
| 1783 ** of at least N bytes in size or NULL if sufficient memory is unavailable. | |
| 1784 ** If M is the size of the prior allocation, then min(N,M) bytes | |
| 1785 ** of the prior allocation are copied into the beginning of buffer returned | |
| 1786 ** by sqlite3_realloc() and the prior allocation is freed. | |
| 1787 ** If sqlite3_realloc() returns NULL, then the prior allocation | |
| 1788 ** is not freed. | |
| 1789 ** | |
| 1790 ** The memory returned by sqlite3_malloc() and sqlite3_realloc() | |
| 1791 ** is always aligned to at least an 8 byte boundary. {END} | |
| 1792 ** | |
| 1793 ** The default implementation of the memory allocation subsystem uses | |
| 1794 ** the malloc(), realloc() and free() provided by the standard C library. | |
| 1795 ** {H17382} However, if SQLite is compiled with the | |
| 1796 ** SQLITE_MEMORY_SIZE=<i>NNN</i> C preprocessor macro (where <i>NNN</i> | |
| 1797 ** is an integer), then SQLite create a static array of at least | |
| 1798 ** <i>NNN</i> bytes in size and uses that array for all of its dynamic | |
| 1799 ** memory allocation needs. {END} Additional memory allocator options | |
| 1800 ** may be added in future releases. | |
| 1801 ** | |
| 1802 ** In SQLite version 3.5.0 and 3.5.1, it was possible to define | |
| 1803 ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in | |
| 1804 ** implementation of these routines to be omitted. That capability | |
| 1805 ** is no longer provided. Only built-in memory allocators can be used. | |
| 1806 ** | |
| 1807 ** The Windows OS interface layer calls | |
| 1808 ** the system malloc() and free() directly when converting | |
| 1809 ** filenames between the UTF-8 encoding used by SQLite | |
| 1810 ** and whatever filename encoding is used by the particular Windows | |
| 1811 ** installation. Memory allocation errors are detected, but | |
| 1812 ** they are reported back as [SQLITE_CANTOPEN] or | |
| 1813 ** [SQLITE_IOERR] rather than [SQLITE_NOMEM]. | |
| 1814 ** | |
| 1815 ** Requirements: | |
| 1816 ** [H17303] [H17304] [H17305] [H17306] [H17310] [H17312] [H17315] [H17318] | |
| 1817 ** [H17321] [H17322] [H17323] | |
| 1818 ** | |
| 1819 ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] | |
| 1820 ** must be either NULL or else pointers obtained from a prior | |
| 1821 ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have | |
| 1822 ** not yet been released. | |
| 1823 ** | |
| 1824 ** The application must not read or write any part of | |
| 1825 ** a block of memory after it has been released using | |
| 1826 ** [sqlite3_free()] or [sqlite3_realloc()]. | |
| 1827 */ | |
| 1828 SQLITE_API void *sqlite3_malloc(int); | |
| 1829 SQLITE_API void *sqlite3_realloc(void*, int); | |
| 1830 SQLITE_API void sqlite3_free(void*); | |
| 1831 | |
| 1832 /* | |
| 1833 ** CAPI3REF: Memory Allocator Statistics {H17370} <S30210> | |
| 1834 ** | |
| 1835 ** SQLite provides these two interfaces for reporting on the status | |
| 1836 ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] | |
| 1837 ** routines, which form the built-in memory allocation subsystem. | |
| 1838 ** | |
| 1839 ** Requirements: | |
| 1840 ** [H17371] [H17373] [H17374] [H17375] | |
| 1841 */ | |
| 1842 SQLITE_API sqlite3_int64 sqlite3_memory_used(void); | |
| 1843 SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag); | |
| 1844 | |
| 1845 /* | |
| 1846 ** CAPI3REF: Pseudo-Random Number Generator {H17390} <S20000> | |
| 1847 ** | |
| 1848 ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to | |
| 1849 ** select random [ROWID | ROWIDs] when inserting new records into a table that | |
| 1850 ** already uses the largest possible [ROWID]. The PRNG is also used for | |
| 1851 ** the build-in random() and randomblob() SQL functions. This interface allows | |
| 1852 ** applications to access the same PRNG for other purposes. | |
| 1853 ** | |
| 1854 ** A call to this routine stores N bytes of randomness into buffer P. | |
| 1855 ** | |
| 1856 ** The first time this routine is invoked (either internally or by | |
| 1857 ** the application) the PRNG is seeded using randomness obtained | |
| 1858 ** from the xRandomness method of the default [sqlite3_vfs] object. | |
| 1859 ** On all subsequent invocations, the pseudo-randomness is generated | |
| 1860 ** internally and without recourse to the [sqlite3_vfs] xRandomness | |
| 1861 ** method. | |
| 1862 ** | |
| 1863 ** Requirements: | |
| 1864 ** [H17392] | |
| 1865 */ | |
| 1866 SQLITE_API void sqlite3_randomness(int N, void *P); | |
| 1867 | |
| 1868 /* | |
| 1869 ** CAPI3REF: Compile-Time Authorization Callbacks {H12500} <S70100> | |
| 1870 ** | |
| 1871 ** This routine registers a authorizer callback with a particular | |
| 1872 ** [database connection], supplied in the first argument. | |
| 1873 ** The authorizer callback is invoked as SQL statements are being compiled | |
| 1874 ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], | |
| 1875 ** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. At various | |
| 1876 ** points during the compilation process, as logic is being created | |
| 1877 ** to perform various actions, the authorizer callback is invoked to | |
| 1878 ** see if those actions are allowed. The authorizer callback should | |
| 1879 ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the | |
| 1880 ** specific action but allow the SQL statement to continue to be | |
| 1881 ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be | |
| 1882 ** rejected with an error. If the authorizer callback returns | |
| 1883 ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] | |
| 1884 ** then the [sqlite3_prepare_v2()] or equivalent call that triggered | |
| 1885 ** the authorizer will fail with an error message. | |
| 1886 ** | |
| 1887 ** When the callback returns [SQLITE_OK], that means the operation | |
| 1888 ** requested is ok. When the callback returns [SQLITE_DENY], the | |
| 1889 ** [sqlite3_prepare_v2()] or equivalent call that triggered the | |
| 1890 ** authorizer will fail with an error message explaining that | |
| 1891 ** access is denied. | |
| 1892 ** | |
| 1893 ** The first parameter to the authorizer callback is a copy of the third | |
| 1894 ** parameter to the sqlite3_set_authorizer() interface. The second parameter | |
| 1895 ** to the callback is an integer [SQLITE_COPY | action code] that specifies | |
| 1896 ** the particular action to be authorized. The third through sixth parameters | |
| 1897 ** to the callback are zero-terminated strings that contain additional | |
| 1898 ** details about the action to be authorized. | |
| 1899 ** | |
| 1900 ** If the action code is [SQLITE_READ] | |
| 1901 ** and the callback returns [SQLITE_IGNORE] then the | |
| 1902 ** [prepared statement] statement is constructed to substitute | |
| 1903 ** a NULL value in place of the table column that would have | |
| 1904 ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] | |
| 1905 ** return can be used to deny an untrusted user access to individual | |
| 1906 ** columns of a table. | |
| 1907 ** If the action code is [SQLITE_DELETE] and the callback returns | |
| 1908 ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the | |
| 1909 ** [truncate optimization] is disabled and all rows are deleted individually. | |
| 1910 ** | |
| 1911 ** An authorizer is used when [sqlite3_prepare | preparing] | |
| 1912 ** SQL statements from an untrusted source, to ensure that the SQL statements | |
| 1913 ** do not try to access data they are not allowed to see, or that they do not | |
| 1914 ** try to execute malicious statements that damage the database. For | |
| 1915 ** example, an application may allow a user to enter arbitrary | |
| 1916 ** SQL queries for evaluation by a database. But the application does | |
| 1917 ** not want the user to be able to make arbitrary changes to the | |
| 1918 ** database. An authorizer could then be put in place while the | |
| 1919 ** user-entered SQL is being [sqlite3_prepare | prepared] that | |
| 1920 ** disallows everything except [SELECT] statements. | |
| 1921 ** | |
| 1922 ** Applications that need to process SQL from untrusted sources | |
| 1923 ** might also consider lowering resource limits using [sqlite3_limit()] | |
| 1924 ** and limiting database size using the [max_page_count] [PRAGMA] | |
| 1925 ** in addition to using an authorizer. | |
| 1926 ** | |
| 1927 ** Only a single authorizer can be in place on a database connection | |
| 1928 ** at a time. Each call to sqlite3_set_authorizer overrides the | |
| 1929 ** previous call. Disable the authorizer by installing a NULL callback. | |
| 1930 ** The authorizer is disabled by default. | |
| 1931 ** | |
| 1932 ** The authorizer callback must not do anything that will modify | |
| 1933 ** the database connection that invoked the authorizer callback. | |
| 1934 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their | |
| 1935 ** database connections for the meaning of "modify" in this paragraph. | |
| 1936 ** | |
| 1937 ** When [sqlite3_prepare_v2()] is used to prepare a statement, the | |
| 1938 ** statement might be re-prepared during [sqlite3_step()] due to a | |
| 1939 ** schema change. Hence, the application should ensure that the | |
| 1940 ** correct authorizer callback remains in place during the [sqlite3_step()]. | |
| 1941 ** | |
| 1942 ** Note that the authorizer callback is invoked only during | |
| 1943 ** [sqlite3_prepare()] or its variants. Authorization is not | |
| 1944 ** performed during statement evaluation in [sqlite3_step()], unless | |
| 1945 ** as stated in the previous paragraph, sqlite3_step() invokes | |
| 1946 ** sqlite3_prepare_v2() to reprepare a statement after a schema change. | |
| 1947 ** | |
| 1948 ** Requirements: | |
| 1949 ** [H12501] [H12502] [H12503] [H12504] [H12505] [H12506] [H12507] [H12510] | |
| 1950 ** [H12511] [H12512] [H12520] [H12521] [H12522] | |
| 1951 */ | |
| 1952 SQLITE_API int sqlite3_set_authorizer( | |
| 1953 sqlite3*, | |
| 1954 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), | |
| 1955 void *pUserData | |
| 1956 ); | |
| 1957 | |
| 1958 /* | |
| 1959 ** CAPI3REF: Authorizer Return Codes {H12590} <H12500> | |
| 1960 ** | |
| 1961 ** The [sqlite3_set_authorizer | authorizer callback function] must | |
| 1962 ** return either [SQLITE_OK] or one of these two constants in order | |
| 1963 ** to signal SQLite whether or not the action is permitted. See the | |
| 1964 ** [sqlite3_set_authorizer | authorizer documentation] for additional | |
| 1965 ** information. | |
| 1966 */ | |
| 1967 #define SQLITE_DENY 1 /* Abort the SQL statement with an error */ | |
| 1968 #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ | |
| 1969 | |
| 1970 /* | |
| 1971 ** CAPI3REF: Authorizer Action Codes {H12550} <H12500> | |
| 1972 ** | |
| 1973 ** The [sqlite3_set_authorizer()] interface registers a callback function | |
| 1974 ** that is invoked to authorize certain SQL statement actions. The | |
| 1975 ** second parameter to the callback is an integer code that specifies | |
| 1976 ** what action is being authorized. These are the integer action codes that | |
| 1977 ** the authorizer callback may be passed. | |
| 1978 ** | |
| 1979 ** These action code values signify what kind of operation is to be | |
| 1980 ** authorized. The 3rd and 4th parameters to the authorization | |
| 1981 ** callback function will be parameters or NULL depending on which of these | |
| 1982 ** codes is used as the second parameter. The 5th parameter to the | |
| 1983 ** authorizer callback is the name of the database ("main", "temp", | |
| 1984 ** etc.) if applicable. The 6th parameter to the authorizer callback | |
| 1985 ** is the name of the inner-most trigger or view that is responsible for | |
| 1986 ** the access attempt or NULL if this access attempt is directly from | |
| 1987 ** top-level SQL code. | |
| 1988 ** | |
| 1989 ** Requirements: | |
| 1990 ** [H12551] [H12552] [H12553] [H12554] | |
| 1991 */ | |
| 1992 /******************************************* 3rd ************ 4th ***********/ | |
| 1993 #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ | |
| 1994 #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ | |
| 1995 #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ | |
| 1996 #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ | |
| 1997 #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ | |
| 1998 #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ | |
| 1999 #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ | |
| 2000 #define SQLITE_CREATE_VIEW 8 /* View Name NULL */ | |
| 2001 #define SQLITE_DELETE 9 /* Table Name NULL */ | |
| 2002 #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ | |
| 2003 #define SQLITE_DROP_TABLE 11 /* Table Name NULL */ | |
| 2004 #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ | |
| 2005 #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ | |
| 2006 #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ | |
| 2007 #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ | |
| 2008 #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ | |
| 2009 #define SQLITE_DROP_VIEW 17 /* View Name NULL */ | |
| 2010 #define SQLITE_INSERT 18 /* Table Name NULL */ | |
| 2011 #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ | |
| 2012 #define SQLITE_READ 20 /* Table Name Column Name */ | |
| 2013 #define SQLITE_SELECT 21 /* NULL NULL */ | |
| 2014 #define SQLITE_TRANSACTION 22 /* Operation NULL */ | |
| 2015 #define SQLITE_UPDATE 23 /* Table Name Column Name */ | |
| 2016 #define SQLITE_ATTACH 24 /* Filename NULL */ | |
| 2017 #define SQLITE_DETACH 25 /* Database Name NULL */ | |
| 2018 #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ | |
| 2019 #define SQLITE_REINDEX 27 /* Index Name NULL */ | |
| 2020 #define SQLITE_ANALYZE 28 /* Table Name NULL */ | |
| 2021 #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ | |
| 2022 #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ | |
| 2023 #define SQLITE_FUNCTION 31 /* NULL Function Name */ | |
| 2024 #define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */ | |
| 2025 #define SQLITE_COPY 0 /* No longer used */ | |
| 2026 | |
| 2027 /* | |
| 2028 ** CAPI3REF: Tracing And Profiling Functions {H12280} <S60400> | |
| 2029 ** EXPERIMENTAL | |
| 2030 ** | |
| 2031 ** These routines register callback functions that can be used for | |
| 2032 ** tracing and profiling the execution of SQL statements. | |
| 2033 ** | |
| 2034 ** The callback function registered by sqlite3_trace() is invoked at | |
| 2035 ** various times when an SQL statement is being run by [sqlite3_step()]. | |
| 2036 ** The callback returns a UTF-8 rendering of the SQL statement text | |
| 2037 ** as the statement first begins executing. Additional callbacks occur | |
| 2038 ** as each triggered subprogram is entered. The callbacks for triggers | |
| 2039 ** contain a UTF-8 SQL comment that identifies the trigger. | |
| 2040 ** | |
| 2041 ** The callback function registered by sqlite3_profile() is invoked | |
| 2042 ** as each SQL statement finishes. The profile callback contains | |
| 2043 ** the original statement text and an estimate of wall-clock time | |
| 2044 ** of how long that statement took to run. | |
| 2045 ** | |
| 2046 ** Requirements: | |
| 2047 ** [H12281] [H12282] [H12283] [H12284] [H12285] [H12287] [H12288] [H12289] | |
| 2048 ** [H12290] | |
| 2049 */ | |
| 2050 SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_trace(sqlite3*, void(*xTrace)(void*
,const char*), void*); | |
| 2051 SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*, | |
| 2052 void(*xProfile)(void*,const char*,sqlite3_uint64), void*); | |
| 2053 | |
| 2054 /* | |
| 2055 ** CAPI3REF: Query Progress Callbacks {H12910} <S60400> | |
| 2056 ** | |
| 2057 ** This routine configures a callback function - the | |
| 2058 ** progress callback - that is invoked periodically during long | |
| 2059 ** running calls to [sqlite3_exec()], [sqlite3_step()] and | |
| 2060 ** [sqlite3_get_table()]. An example use for this | |
| 2061 ** interface is to keep a GUI updated during a large query. | |
| 2062 ** | |
| 2063 ** If the progress callback returns non-zero, the operation is | |
| 2064 ** interrupted. This feature can be used to implement a | |
| 2065 ** "Cancel" button on a GUI progress dialog box. | |
| 2066 ** | |
| 2067 ** The progress handler must not do anything that will modify | |
| 2068 ** the database connection that invoked the progress handler. | |
| 2069 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their | |
| 2070 ** database connections for the meaning of "modify" in this paragraph. | |
| 2071 ** | |
| 2072 ** Requirements: | |
| 2073 ** [H12911] [H12912] [H12913] [H12914] [H12915] [H12916] [H12917] [H12918] | |
| 2074 ** | |
| 2075 */ | |
| 2076 SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); | |
| 2077 | |
| 2078 /* | |
| 2079 ** CAPI3REF: Opening A New Database Connection {H12700} <S40200> | |
| 2080 ** | |
| 2081 ** These routines open an SQLite database file whose name is given by the | |
| 2082 ** filename argument. The filename argument is interpreted as UTF-8 for | |
| 2083 ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte | |
| 2084 ** order for sqlite3_open16(). A [database connection] handle is usually | |
| 2085 ** returned in *ppDb, even if an error occurs. The only exception is that | |
| 2086 ** if SQLite is unable to allocate memory to hold the [sqlite3] object, | |
| 2087 ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3] | |
| 2088 ** object. If the database is opened (and/or created) successfully, then | |
| 2089 ** [SQLITE_OK] is returned. Otherwise an [error code] is returned. The | |
| 2090 ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain | |
| 2091 ** an English language description of the error. | |
| 2092 ** | |
| 2093 ** The default encoding for the database will be UTF-8 if | |
| 2094 ** sqlite3_open() or sqlite3_open_v2() is called and | |
| 2095 ** UTF-16 in the native byte order if sqlite3_open16() is used. | |
| 2096 ** | |
| 2097 ** Whether or not an error occurs when it is opened, resources | |
| 2098 ** associated with the [database connection] handle should be released by | |
| 2099 ** passing it to [sqlite3_close()] when it is no longer required. | |
| 2100 ** | |
| 2101 ** The sqlite3_open_v2() interface works like sqlite3_open() | |
| 2102 ** except that it accepts two additional parameters for additional control | |
| 2103 ** over the new database connection. The flags parameter can take one of | |
| 2104 ** the following three values, optionally combined with the | |
| 2105 ** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE], | |
| 2106 ** and/or [SQLITE_OPEN_PRIVATECACHE] flags: | |
| 2107 ** | |
| 2108 ** <dl> | |
| 2109 ** <dt>[SQLITE_OPEN_READONLY]</dt> | |
| 2110 ** <dd>The database is opened in read-only mode. If the database does not | |
| 2111 ** already exist, an error is returned.</dd> | |
| 2112 ** | |
| 2113 ** <dt>[SQLITE_OPEN_READWRITE]</dt> | |
| 2114 ** <dd>The database is opened for reading and writing if possible, or reading | |
| 2115 ** only if the file is write protected by the operating system. In either | |
| 2116 ** case the database must already exist, otherwise an error is returned.</dd> | |
| 2117 ** | |
| 2118 ** <dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt> | |
| 2119 ** <dd>The database is opened for reading and writing, and is creates it if | |
| 2120 ** it does not already exist. This is the behavior that is always used for | |
| 2121 ** sqlite3_open() and sqlite3_open16().</dd> | |
| 2122 ** </dl> | |
| 2123 ** | |
| 2124 ** If the 3rd parameter to sqlite3_open_v2() is not one of the | |
| 2125 ** combinations shown above or one of the combinations shown above combined | |
| 2126 ** with the [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], | |
| 2127 ** [SQLITE_OPEN_SHAREDCACHE] and/or [SQLITE_OPEN_SHAREDCACHE] flags, | |
| 2128 ** then the behavior is undefined. | |
| 2129 ** | |
| 2130 ** If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection | |
| 2131 ** opens in the multi-thread [threading mode] as long as the single-thread | |
| 2132 ** mode has not been set at compile-time or start-time. If the | |
| 2133 ** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens | |
| 2134 ** in the serialized [threading mode] unless single-thread was | |
| 2135 ** previously selected at compile-time or start-time. | |
| 2136 ** The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be | |
| 2137 ** eligible to use [shared cache mode], regardless of whether or not shared | |
| 2138 ** cache is enabled using [sqlite3_enable_shared_cache()]. The | |
| 2139 ** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not | |
| 2140 ** participate in [shared cache mode] even if it is enabled. | |
| 2141 ** | |
| 2142 ** If the filename is ":memory:", then a private, temporary in-memory database | |
| 2143 ** is created for the connection. This in-memory database will vanish when | |
| 2144 ** the database connection is closed. Future versions of SQLite might | |
| 2145 ** make use of additional special filenames that begin with the ":" character. | |
| 2146 ** It is recommended that when a database filename actually does begin with | |
| 2147 ** a ":" character you should prefix the filename with a pathname such as | |
| 2148 ** "./" to avoid ambiguity. | |
| 2149 ** | |
| 2150 ** If the filename is an empty string, then a private, temporary | |
| 2151 ** on-disk database will be created. This private database will be | |
| 2152 ** automatically deleted as soon as the database connection is closed. | |
| 2153 ** | |
| 2154 ** The fourth parameter to sqlite3_open_v2() is the name of the | |
| 2155 ** [sqlite3_vfs] object that defines the operating system interface that | |
| 2156 ** the new database connection should use. If the fourth parameter is | |
| 2157 ** a NULL pointer then the default [sqlite3_vfs] object is used. | |
| 2158 ** | |
| 2159 ** <b>Note to Windows users:</b> The encoding used for the filename argument | |
| 2160 ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever | |
| 2161 ** codepage is currently defined. Filenames containing international | |
| 2162 ** characters must be converted to UTF-8 prior to passing them into | |
| 2163 ** sqlite3_open() or sqlite3_open_v2(). | |
| 2164 ** | |
| 2165 ** Requirements: | |
| 2166 ** [H12701] [H12702] [H12703] [H12704] [H12706] [H12707] [H12709] [H12711] | |
| 2167 ** [H12712] [H12713] [H12714] [H12717] [H12719] [H12721] [H12723] | |
| 2168 */ | |
| 2169 SQLITE_API int sqlite3_open( | |
| 2170 const char *filename, /* Database filename (UTF-8) */ | |
| 2171 sqlite3 **ppDb /* OUT: SQLite db handle */ | |
| 2172 ); | |
| 2173 SQLITE_API int sqlite3_open16( | |
| 2174 const void *filename, /* Database filename (UTF-16) */ | |
| 2175 sqlite3 **ppDb /* OUT: SQLite db handle */ | |
| 2176 ); | |
| 2177 SQLITE_API int sqlite3_open_v2( | |
| 2178 const char *filename, /* Database filename (UTF-8) */ | |
| 2179 sqlite3 **ppDb, /* OUT: SQLite db handle */ | |
| 2180 int flags, /* Flags */ | |
| 2181 const char *zVfs /* Name of VFS module to use */ | |
| 2182 ); | |
| 2183 | |
| 2184 /* | |
| 2185 ** CAPI3REF: Error Codes And Messages {H12800} <S60200> | |
| 2186 ** | |
| 2187 ** The sqlite3_errcode() interface returns the numeric [result code] or | |
| 2188 ** [extended result code] for the most recent failed sqlite3_* API call | |
| 2189 ** associated with a [database connection]. If a prior API call failed | |
| 2190 ** but the most recent API call succeeded, the return value from | |
| 2191 ** sqlite3_errcode() is undefined. The sqlite3_extended_errcode() | |
| 2192 ** interface is the same except that it always returns the | |
| 2193 ** [extended result code] even when extended result codes are | |
| 2194 ** disabled. | |
| 2195 ** | |
| 2196 ** The sqlite3_errmsg() and sqlite3_errmsg16() return English-language | |
| 2197 ** text that describes the error, as either UTF-8 or UTF-16 respectively. | |
| 2198 ** Memory to hold the error message string is managed internally. | |
| 2199 ** The application does not need to worry about freeing the result. | |
| 2200 ** However, the error string might be overwritten or deallocated by | |
| 2201 ** subsequent calls to other SQLite interface functions. | |
| 2202 ** | |
| 2203 ** When the serialized [threading mode] is in use, it might be the | |
| 2204 ** case that a second error occurs on a separate thread in between | |
| 2205 ** the time of the first error and the call to these interfaces. | |
| 2206 ** When that happens, the second error will be reported since these | |
| 2207 ** interfaces always report the most recent result. To avoid | |
| 2208 ** this, each thread can obtain exclusive use of the [database connection] D | |
| 2209 ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning | |
| 2210 ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after | |
| 2211 ** all calls to the interfaces listed here are completed. | |
| 2212 ** | |
| 2213 ** If an interface fails with SQLITE_MISUSE, that means the interface | |
| 2214 ** was invoked incorrectly by the application. In that case, the | |
| 2215 ** error code and message may or may not be set. | |
| 2216 ** | |
| 2217 ** Requirements: | |
| 2218 ** [H12801] [H12802] [H12803] [H12807] [H12808] [H12809] | |
| 2219 */ | |
| 2220 SQLITE_API int sqlite3_errcode(sqlite3 *db); | |
| 2221 SQLITE_API int sqlite3_extended_errcode(sqlite3 *db); | |
| 2222 SQLITE_API const char *sqlite3_errmsg(sqlite3*); | |
| 2223 SQLITE_API const void *sqlite3_errmsg16(sqlite3*); | |
| 2224 | |
| 2225 /* | |
| 2226 ** CAPI3REF: SQL Statement Object {H13000} <H13010> | |
| 2227 ** KEYWORDS: {prepared statement} {prepared statements} | |
| 2228 ** | |
| 2229 ** An instance of this object represents a single SQL statement. | |
| 2230 ** This object is variously known as a "prepared statement" or a | |
| 2231 ** "compiled SQL statement" or simply as a "statement". | |
| 2232 ** | |
| 2233 ** The life of a statement object goes something like this: | |
| 2234 ** | |
| 2235 ** <ol> | |
| 2236 ** <li> Create the object using [sqlite3_prepare_v2()] or a related | |
| 2237 ** function. | |
| 2238 ** <li> Bind values to [host parameters] using the sqlite3_bind_*() | |
| 2239 ** interfaces. | |
| 2240 ** <li> Run the SQL by calling [sqlite3_step()] one or more times. | |
| 2241 ** <li> Reset the statement using [sqlite3_reset()] then go back | |
| 2242 ** to step 2. Do this zero or more times. | |
| 2243 ** <li> Destroy the object using [sqlite3_finalize()]. | |
| 2244 ** </ol> | |
| 2245 ** | |
| 2246 ** Refer to documentation on individual methods above for additional | |
| 2247 ** information. | |
| 2248 */ | |
| 2249 typedef struct sqlite3_stmt sqlite3_stmt; | |
| 2250 | |
| 2251 /* | |
| 2252 ** CAPI3REF: Run-time Limits {H12760} <S20600> | |
| 2253 ** | |
| 2254 ** This interface allows the size of various constructs to be limited | |
| 2255 ** on a connection by connection basis. The first parameter is the | |
| 2256 ** [database connection] whose limit is to be set or queried. The | |
| 2257 ** second parameter is one of the [limit categories] that define a | |
| 2258 ** class of constructs to be size limited. The third parameter is the | |
| 2259 ** new limit for that construct. The function returns the old limit. | |
| 2260 ** | |
| 2261 ** If the new limit is a negative number, the limit is unchanged. | |
| 2262 ** For the limit category of SQLITE_LIMIT_XYZ there is a | |
| 2263 ** [limits | hard upper bound] | |
| 2264 ** set by a compile-time C preprocessor macro named | |
| 2265 ** [limits | SQLITE_MAX_XYZ]. | |
| 2266 ** (The "_LIMIT_" in the name is changed to "_MAX_".) | |
| 2267 ** Attempts to increase a limit above its hard upper bound are | |
| 2268 ** silently truncated to the hard upper limit. | |
| 2269 ** | |
| 2270 ** Run time limits are intended for use in applications that manage | |
| 2271 ** both their own internal database and also databases that are controlled | |
| 2272 ** by untrusted external sources. An example application might be a | |
| 2273 ** web browser that has its own databases for storing history and | |
| 2274 ** separate databases controlled by JavaScript applications downloaded | |
| 2275 ** off the Internet. The internal databases can be given the | |
| 2276 ** large, default limits. Databases managed by external sources can | |
| 2277 ** be given much smaller limits designed to prevent a denial of service | |
| 2278 ** attack. Developers might also want to use the [sqlite3_set_authorizer()] | |
| 2279 ** interface to further control untrusted SQL. The size of the database | |
| 2280 ** created by an untrusted script can be contained using the | |
| 2281 ** [max_page_count] [PRAGMA]. | |
| 2282 ** | |
| 2283 ** New run-time limit categories may be added in future releases. | |
| 2284 ** | |
| 2285 ** Requirements: | |
| 2286 ** [H12762] [H12766] [H12769] | |
| 2287 */ | |
| 2288 SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal); | |
| 2289 | |
| 2290 /* | |
| 2291 ** CAPI3REF: Run-Time Limit Categories {H12790} <H12760> | |
| 2292 ** KEYWORDS: {limit category} {limit categories} | |
| 2293 ** | |
| 2294 ** These constants define various performance limits | |
| 2295 ** that can be lowered at run-time using [sqlite3_limit()]. | |
| 2296 ** The synopsis of the meanings of the various limits is shown below. | |
| 2297 ** Additional information is available at [limits | Limits in SQLite]. | |
| 2298 ** | |
| 2299 ** <dl> | |
| 2300 ** <dt>SQLITE_LIMIT_LENGTH</dt> | |
| 2301 ** <dd>The maximum size of any string or BLOB or table row.<dd> | |
| 2302 ** | |
| 2303 ** <dt>SQLITE_LIMIT_SQL_LENGTH</dt> | |
| 2304 ** <dd>The maximum length of an SQL statement.</dd> | |
| 2305 ** | |
| 2306 ** <dt>SQLITE_LIMIT_COLUMN</dt> | |
| 2307 ** <dd>The maximum number of columns in a table definition or in the | |
| 2308 ** result set of a [SELECT] or the maximum number of columns in an index | |
| 2309 ** or in an ORDER BY or GROUP BY clause.</dd> | |
| 2310 ** | |
| 2311 ** <dt>SQLITE_LIMIT_EXPR_DEPTH</dt> | |
| 2312 ** <dd>The maximum depth of the parse tree on any expression.</dd> | |
| 2313 ** | |
| 2314 ** <dt>SQLITE_LIMIT_COMPOUND_SELECT</dt> | |
| 2315 ** <dd>The maximum number of terms in a compound SELECT statement.</dd> | |
| 2316 ** | |
| 2317 ** <dt>SQLITE_LIMIT_VDBE_OP</dt> | |
| 2318 ** <dd>The maximum number of instructions in a virtual machine program | |
| 2319 ** used to implement an SQL statement.</dd> | |
| 2320 ** | |
| 2321 ** <dt>SQLITE_LIMIT_FUNCTION_ARG</dt> | |
| 2322 ** <dd>The maximum number of arguments on a function.</dd> | |
| 2323 ** | |
| 2324 ** <dt>SQLITE_LIMIT_ATTACHED</dt> | |
| 2325 ** <dd>The maximum number of [ATTACH | attached databases].</dd> | |
| 2326 ** | |
| 2327 ** <dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt> | |
| 2328 ** <dd>The maximum length of the pattern argument to the [LIKE] or | |
| 2329 ** [GLOB] operators.</dd> | |
| 2330 ** | |
| 2331 ** <dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt> | |
| 2332 ** <dd>The maximum number of variables in an SQL statement that can | |
| 2333 ** be bound.</dd> | |
| 2334 ** | |
| 2335 ** <dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt> | |
| 2336 ** <dd>The maximum depth of recursion for triggers.</dd> | |
| 2337 ** </dl> | |
| 2338 */ | |
| 2339 #define SQLITE_LIMIT_LENGTH 0 | |
| 2340 #define SQLITE_LIMIT_SQL_LENGTH 1 | |
| 2341 #define SQLITE_LIMIT_COLUMN 2 | |
| 2342 #define SQLITE_LIMIT_EXPR_DEPTH 3 | |
| 2343 #define SQLITE_LIMIT_COMPOUND_SELECT 4 | |
| 2344 #define SQLITE_LIMIT_VDBE_OP 5 | |
| 2345 #define SQLITE_LIMIT_FUNCTION_ARG 6 | |
| 2346 #define SQLITE_LIMIT_ATTACHED 7 | |
| 2347 #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8 | |
| 2348 #define SQLITE_LIMIT_VARIABLE_NUMBER 9 | |
| 2349 #define SQLITE_LIMIT_TRIGGER_DEPTH 10 | |
| 2350 | |
| 2351 /* | |
| 2352 ** CAPI3REF: Compiling An SQL Statement {H13010} <S10000> | |
| 2353 ** KEYWORDS: {SQL statement compiler} | |
| 2354 ** | |
| 2355 ** To execute an SQL query, it must first be compiled into a byte-code | |
| 2356 ** program using one of these routines. | |
| 2357 ** | |
| 2358 ** The first argument, "db", is a [database connection] obtained from a | |
| 2359 ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or | |
| 2360 ** [sqlite3_open16()]. The database connection must not have been closed. | |
| 2361 ** | |
| 2362 ** The second argument, "zSql", is the statement to be compiled, encoded | |
| 2363 ** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2() | |
| 2364 ** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2() | |
| 2365 ** use UTF-16. | |
| 2366 ** | |
| 2367 ** If the nByte argument is less than zero, then zSql is read up to the | |
| 2368 ** first zero terminator. If nByte is non-negative, then it is the maximum | |
| 2369 ** number of bytes read from zSql. When nByte is non-negative, the | |
| 2370 ** zSql string ends at either the first '\000' or '\u0000' character or | |
| 2371 ** the nByte-th byte, whichever comes first. If the caller knows | |
| 2372 ** that the supplied string is nul-terminated, then there is a small | |
| 2373 ** performance advantage to be gained by passing an nByte parameter that | |
| 2374 ** is equal to the number of bytes in the input string <i>including</i> | |
| 2375 ** the nul-terminator bytes. | |
| 2376 ** | |
| 2377 ** If pzTail is not NULL then *pzTail is made to point to the first byte | |
| 2378 ** past the end of the first SQL statement in zSql. These routines only | |
| 2379 ** compile the first statement in zSql, so *pzTail is left pointing to | |
| 2380 ** what remains uncompiled. | |
| 2381 ** | |
| 2382 ** *ppStmt is left pointing to a compiled [prepared statement] that can be | |
| 2383 ** executed using [sqlite3_step()]. If there is an error, *ppStmt is set | |
| 2384 ** to NULL. If the input text contains no SQL (if the input is an empty | |
| 2385 ** string or a comment) then *ppStmt is set to NULL. | |
| 2386 ** The calling procedure is responsible for deleting the compiled | |
| 2387 ** SQL statement using [sqlite3_finalize()] after it has finished with it. | |
| 2388 ** ppStmt may not be NULL. | |
| 2389 ** | |
| 2390 ** On success, [SQLITE_OK] is returned, otherwise an [error code] is returned. | |
| 2391 ** | |
| 2392 ** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are | |
| 2393 ** recommended for all new programs. The two older interfaces are retained | |
| 2394 ** for backwards compatibility, but their use is discouraged. | |
| 2395 ** In the "v2" interfaces, the prepared statement | |
| 2396 ** that is returned (the [sqlite3_stmt] object) contains a copy of the | |
| 2397 ** original SQL text. This causes the [sqlite3_step()] interface to | |
| 2398 ** behave a differently in two ways: | |
| 2399 ** | |
| 2400 ** <ol> | |
| 2401 ** <li> | |
| 2402 ** If the database schema changes, instead of returning [SQLITE_SCHEMA] as it | |
| 2403 ** always used to do, [sqlite3_step()] will automatically recompile the SQL | |
| 2404 ** statement and try to run it again. If the schema has changed in | |
| 2405 ** a way that makes the statement no longer valid, [sqlite3_step()] will still | |
| 2406 ** return [SQLITE_SCHEMA]. But unlike the legacy behavior, [SQLITE_SCHEMA] is | |
| 2407 ** now a fatal error. Calling [sqlite3_prepare_v2()] again will not make the | |
| 2408 ** error go away. Note: use [sqlite3_errmsg()] to find the text | |
| 2409 ** of the parsing error that results in an [SQLITE_SCHEMA] return. | |
| 2410 ** </li> | |
| 2411 ** | |
| 2412 ** <li> | |
| 2413 ** When an error occurs, [sqlite3_step()] will return one of the detailed | |
| 2414 ** [error codes] or [extended error codes]. The legacy behavior was that | |
| 2415 ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code | |
| 2416 ** and you would have to make a second call to [sqlite3_reset()] in order | |
| 2417 ** to find the underlying cause of the problem. With the "v2" prepare | |
| 2418 ** interfaces, the underlying reason for the error is returned immediately. | |
| 2419 ** </li> | |
| 2420 ** </ol> | |
| 2421 ** | |
| 2422 ** Requirements: | |
| 2423 ** [H13011] [H13012] [H13013] [H13014] [H13015] [H13016] [H13019] [H13021] | |
| 2424 ** | |
| 2425 */ | |
| 2426 SQLITE_API int sqlite3_prepare( | |
| 2427 sqlite3 *db, /* Database handle */ | |
| 2428 const char *zSql, /* SQL statement, UTF-8 encoded */ | |
| 2429 int nByte, /* Maximum length of zSql in bytes. */ | |
| 2430 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ | |
| 2431 const char **pzTail /* OUT: Pointer to unused portion of zSql */ | |
| 2432 ); | |
| 2433 SQLITE_API int sqlite3_prepare_v2( | |
| 2434 sqlite3 *db, /* Database handle */ | |
| 2435 const char *zSql, /* SQL statement, UTF-8 encoded */ | |
| 2436 int nByte, /* Maximum length of zSql in bytes. */ | |
| 2437 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ | |
| 2438 const char **pzTail /* OUT: Pointer to unused portion of zSql */ | |
| 2439 ); | |
| 2440 SQLITE_API int sqlite3_prepare16( | |
| 2441 sqlite3 *db, /* Database handle */ | |
| 2442 const void *zSql, /* SQL statement, UTF-16 encoded */ | |
| 2443 int nByte, /* Maximum length of zSql in bytes. */ | |
| 2444 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ | |
| 2445 const void **pzTail /* OUT: Pointer to unused portion of zSql */ | |
| 2446 ); | |
| 2447 SQLITE_API int sqlite3_prepare16_v2( | |
| 2448 sqlite3 *db, /* Database handle */ | |
| 2449 const void *zSql, /* SQL statement, UTF-16 encoded */ | |
| 2450 int nByte, /* Maximum length of zSql in bytes. */ | |
| 2451 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ | |
| 2452 const void **pzTail /* OUT: Pointer to unused portion of zSql */ | |
| 2453 ); | |
| 2454 | |
| 2455 /* | |
| 2456 ** CAPI3REF: Retrieving Statement SQL {H13100} <H13000> | |
| 2457 ** | |
| 2458 ** This interface can be used to retrieve a saved copy of the original | |
| 2459 ** SQL text used to create a [prepared statement] if that statement was | |
| 2460 ** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()]. | |
| 2461 ** | |
| 2462 ** Requirements: | |
| 2463 ** [H13101] [H13102] [H13103] | |
| 2464 */ | |
| 2465 SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt); | |
| 2466 | |
| 2467 /* | |
| 2468 ** CAPI3REF: Dynamically Typed Value Object {H15000} <S20200> | |
| 2469 ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} | |
| 2470 ** | |
| 2471 ** SQLite uses the sqlite3_value object to represent all values | |
| 2472 ** that can be stored in a database table. SQLite uses dynamic typing | |
| 2473 ** for the values it stores. Values stored in sqlite3_value objects | |
| 2474 ** can be integers, floating point values, strings, BLOBs, or NULL. | |
| 2475 ** | |
| 2476 ** An sqlite3_value object may be either "protected" or "unprotected". | |
| 2477 ** Some interfaces require a protected sqlite3_value. Other interfaces | |
| 2478 ** will accept either a protected or an unprotected sqlite3_value. | |
| 2479 ** Every interface that accepts sqlite3_value arguments specifies | |
| 2480 ** whether or not it requires a protected sqlite3_value. | |
| 2481 ** | |
| 2482 ** The terms "protected" and "unprotected" refer to whether or not | |
| 2483 ** a mutex is held. A internal mutex is held for a protected | |
| 2484 ** sqlite3_value object but no mutex is held for an unprotected | |
| 2485 ** sqlite3_value object. If SQLite is compiled to be single-threaded | |
| 2486 ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0) | |
| 2487 ** or if SQLite is run in one of reduced mutex modes | |
| 2488 ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD] | |
| 2489 ** then there is no distinction between protected and unprotected | |
| 2490 ** sqlite3_value objects and they can be used interchangeably. However, | |
| 2491 ** for maximum code portability it is recommended that applications | |
| 2492 ** still make the distinction between between protected and unprotected | |
| 2493 ** sqlite3_value objects even when not strictly required. | |
| 2494 ** | |
| 2495 ** The sqlite3_value objects that are passed as parameters into the | |
| 2496 ** implementation of [application-defined SQL functions] are protected. | |
| 2497 ** The sqlite3_value object returned by | |
| 2498 ** [sqlite3_column_value()] is unprotected. | |
| 2499 ** Unprotected sqlite3_value objects may only be used with | |
| 2500 ** [sqlite3_result_value()] and [sqlite3_bind_value()]. | |
| 2501 ** The [sqlite3_value_blob | sqlite3_value_type()] family of | |
| 2502 ** interfaces require protected sqlite3_value objects. | |
| 2503 */ | |
| 2504 typedef struct Mem sqlite3_value; | |
| 2505 | |
| 2506 /* | |
| 2507 ** CAPI3REF: SQL Function Context Object {H16001} <S20200> | |
| 2508 ** | |
| 2509 ** The context in which an SQL function executes is stored in an | |
| 2510 ** sqlite3_context object. A pointer to an sqlite3_context object | |
| 2511 ** is always first parameter to [application-defined SQL functions]. | |
| 2512 ** The application-defined SQL function implementation will pass this | |
| 2513 ** pointer through into calls to [sqlite3_result_int | sqlite3_result()], | |
| 2514 ** [sqlite3_aggregate_context()], [sqlite3_user_data()], | |
| 2515 ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()], | |
| 2516 ** and/or [sqlite3_set_auxdata()]. | |
| 2517 */ | |
| 2518 typedef struct sqlite3_context sqlite3_context; | |
| 2519 | |
| 2520 /* | |
| 2521 ** CAPI3REF: Binding Values To Prepared Statements {H13500} <S70300> | |
| 2522 ** KEYWORDS: {host parameter} {host parameters} {host parameter name} | |
| 2523 ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding} | |
| 2524 ** | |
| 2525 ** In the SQL strings input to [sqlite3_prepare_v2()] and its variants, | |
| 2526 ** literals may be replaced by a [parameter] that matches one of following | |
| 2527 ** templates: | |
| 2528 ** | |
| 2529 ** <ul> | |
| 2530 ** <li> ? | |
| 2531 ** <li> ?NNN | |
| 2532 ** <li> :VVV | |
| 2533 ** <li> @VVV | |
| 2534 ** <li> $VVV | |
| 2535 ** </ul> | |
| 2536 ** | |
| 2537 ** In the templates above, NNN represents an integer literal, | |
| 2538 ** and VVV represents an alphanumeric identifer. The values of these | |
| 2539 ** parameters (also called "host parameter names" or "SQL parameters") | |
| 2540 ** can be set using the sqlite3_bind_*() routines defined here. | |
| 2541 ** | |
| 2542 ** The first argument to the sqlite3_bind_*() routines is always | |
| 2543 ** a pointer to the [sqlite3_stmt] object returned from | |
| 2544 ** [sqlite3_prepare_v2()] or its variants. | |
| 2545 ** | |
| 2546 ** The second argument is the index of the SQL parameter to be set. | |
| 2547 ** The leftmost SQL parameter has an index of 1. When the same named | |
| 2548 ** SQL parameter is used more than once, second and subsequent | |
| 2549 ** occurrences have the same index as the first occurrence. | |
| 2550 ** The index for named parameters can be looked up using the | |
| 2551 ** [sqlite3_bind_parameter_index()] API if desired. The index | |
| 2552 ** for "?NNN" parameters is the value of NNN. | |
| 2553 ** The NNN value must be between 1 and the [sqlite3_limit()] | |
| 2554 ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999). | |
| 2555 ** | |
| 2556 ** The third argument is the value to bind to the parameter. | |
| 2557 ** | |
| 2558 ** In those routines that have a fourth argument, its value is the | |
| 2559 ** number of bytes in the parameter. To be clear: the value is the | |
| 2560 ** number of <u>bytes</u> in the value, not the number of characters. | |
| 2561 ** If the fourth parameter is negative, the length of the string is | |
| 2562 ** the number of bytes up to the first zero terminator. | |
| 2563 ** | |
| 2564 ** The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and | |
| 2565 ** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or | |
| 2566 ** string after SQLite has finished with it. If the fifth argument is | |
| 2567 ** the special value [SQLITE_STATIC], then SQLite assumes that the | |
| 2568 ** information is in static, unmanaged space and does not need to be freed. | |
| 2569 ** If the fifth argument has the value [SQLITE_TRANSIENT], then | |
| 2570 ** SQLite makes its own private copy of the data immediately, before | |
| 2571 ** the sqlite3_bind_*() routine returns. | |
| 2572 ** | |
| 2573 ** The sqlite3_bind_zeroblob() routine binds a BLOB of length N that | |
| 2574 ** is filled with zeroes. A zeroblob uses a fixed amount of memory | |
| 2575 ** (just an integer to hold its size) while it is being processed. | |
| 2576 ** Zeroblobs are intended to serve as placeholders for BLOBs whose | |
| 2577 ** content is later written using | |
| 2578 ** [sqlite3_blob_open | incremental BLOB I/O] routines. | |
| 2579 ** A negative value for the zeroblob results in a zero-length BLOB. | |
| 2580 ** | |
| 2581 ** The sqlite3_bind_*() routines must be called after | |
| 2582 ** [sqlite3_prepare_v2()] (and its variants) or [sqlite3_reset()] and | |
| 2583 ** before [sqlite3_step()]. | |
| 2584 ** Bindings are not cleared by the [sqlite3_reset()] routine. | |
| 2585 ** Unbound parameters are interpreted as NULL. | |
| 2586 ** | |
| 2587 ** These routines return [SQLITE_OK] on success or an error code if | |
| 2588 ** anything goes wrong. [SQLITE_RANGE] is returned if the parameter | |
| 2589 ** index is out of range. [SQLITE_NOMEM] is returned if malloc() fails. | |
| 2590 ** [SQLITE_MISUSE] might be returned if these routines are called on a | |
| 2591 ** virtual machine that is the wrong state or which has already been finalized. | |
| 2592 ** Detection of misuse is unreliable. Applications should not depend | |
| 2593 ** on SQLITE_MISUSE returns. SQLITE_MISUSE is intended to indicate a | |
| 2594 ** a logic error in the application. Future versions of SQLite might | |
| 2595 ** panic rather than return SQLITE_MISUSE. | |
| 2596 ** | |
| 2597 ** See also: [sqlite3_bind_parameter_count()], | |
| 2598 ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()]. | |
| 2599 ** | |
| 2600 ** Requirements: | |
| 2601 ** [H13506] [H13509] [H13512] [H13515] [H13518] [H13521] [H13524] [H13527] | |
| 2602 ** [H13530] [H13533] [H13536] [H13539] [H13542] [H13545] [H13548] [H13551] | |
| 2603 ** | |
| 2604 */ | |
| 2605 SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)
(void*)); | |
| 2606 SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double); | |
| 2607 SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int); | |
| 2608 SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); | |
| 2609 SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int); | |
| 2610 SQLITE_API int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)
(void*)); | |
| 2611 SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)
(void*)); | |
| 2612 SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); | |
| 2613 SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); | |
| 2614 | |
| 2615 /* | |
| 2616 ** CAPI3REF: Number Of SQL Parameters {H13600} <S70300> | |
| 2617 ** | |
| 2618 ** This routine can be used to find the number of [SQL parameters] | |
| 2619 ** in a [prepared statement]. SQL parameters are tokens of the | |
| 2620 ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as | |
| 2621 ** placeholders for values that are [sqlite3_bind_blob | bound] | |
| 2622 ** to the parameters at a later time. | |
| 2623 ** | |
| 2624 ** This routine actually returns the index of the largest (rightmost) | |
| 2625 ** parameter. For all forms except ?NNN, this will correspond to the | |
| 2626 ** number of unique parameters. If parameters of the ?NNN are used, | |
| 2627 ** there may be gaps in the list. | |
| 2628 ** | |
| 2629 ** See also: [sqlite3_bind_blob|sqlite3_bind()], | |
| 2630 ** [sqlite3_bind_parameter_name()], and | |
| 2631 ** [sqlite3_bind_parameter_index()]. | |
| 2632 ** | |
| 2633 ** Requirements: | |
| 2634 ** [H13601] | |
| 2635 */ | |
| 2636 SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*); | |
| 2637 | |
| 2638 /* | |
| 2639 ** CAPI3REF: Name Of A Host Parameter {H13620} <S70300> | |
| 2640 ** | |
| 2641 ** This routine returns a pointer to the name of the n-th | |
| 2642 ** [SQL parameter] in a [prepared statement]. | |
| 2643 ** SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA" | |
| 2644 ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA" | |
| 2645 ** respectively. | |
| 2646 ** In other words, the initial ":" or "$" or "@" or "?" | |
| 2647 ** is included as part of the name. | |
| 2648 ** Parameters of the form "?" without a following integer have no name | |
| 2649 ** and are also referred to as "anonymous parameters". | |
| 2650 ** | |
| 2651 ** The first host parameter has an index of 1, not 0. | |
| 2652 ** | |
| 2653 ** If the value n is out of range or if the n-th parameter is | |
| 2654 ** nameless, then NULL is returned. The returned string is | |
| 2655 ** always in UTF-8 encoding even if the named parameter was | |
| 2656 ** originally specified as UTF-16 in [sqlite3_prepare16()] or | |
| 2657 ** [sqlite3_prepare16_v2()]. | |
| 2658 ** | |
| 2659 ** See also: [sqlite3_bind_blob|sqlite3_bind()], | |
| 2660 ** [sqlite3_bind_parameter_count()], and | |
| 2661 ** [sqlite3_bind_parameter_index()]. | |
| 2662 ** | |
| 2663 ** Requirements: | |
| 2664 ** [H13621] | |
| 2665 */ | |
| 2666 SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); | |
| 2667 | |
| 2668 /* | |
| 2669 ** CAPI3REF: Index Of A Parameter With A Given Name {H13640} <S70300> | |
| 2670 ** | |
| 2671 ** Return the index of an SQL parameter given its name. The | |
| 2672 ** index value returned is suitable for use as the second | |
| 2673 ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. A zero | |
| 2674 ** is returned if no matching parameter is found. The parameter | |
| 2675 ** name must be given in UTF-8 even if the original statement | |
| 2676 ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()]. | |
| 2677 ** | |
| 2678 ** See also: [sqlite3_bind_blob|sqlite3_bind()], | |
| 2679 ** [sqlite3_bind_parameter_count()], and | |
| 2680 ** [sqlite3_bind_parameter_index()]. | |
| 2681 ** | |
| 2682 ** Requirements: | |
| 2683 ** [H13641] | |
| 2684 */ | |
| 2685 SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); | |
| 2686 | |
| 2687 /* | |
| 2688 ** CAPI3REF: Reset All Bindings On A Prepared Statement {H13660} <S70300> | |
| 2689 ** | |
| 2690 ** Contrary to the intuition of many, [sqlite3_reset()] does not reset | |
| 2691 ** the [sqlite3_bind_blob | bindings] on a [prepared statement]. | |
| 2692 ** Use this routine to reset all host parameters to NULL. | |
| 2693 ** | |
| 2694 ** Requirements: | |
| 2695 ** [H13661] | |
| 2696 */ | |
| 2697 SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*); | |
| 2698 | |
| 2699 /* | |
| 2700 ** CAPI3REF: Number Of Columns In A Result Set {H13710} <S10700> | |
| 2701 ** | |
| 2702 ** Return the number of columns in the result set returned by the | |
| 2703 ** [prepared statement]. This routine returns 0 if pStmt is an SQL | |
| 2704 ** statement that does not return data (for example an [UPDATE]). | |
| 2705 ** | |
| 2706 ** Requirements: | |
| 2707 ** [H13711] | |
| 2708 */ | |
| 2709 SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt); | |
| 2710 | |
| 2711 /* | |
| 2712 ** CAPI3REF: Column Names In A Result Set {H13720} <S10700> | |
| 2713 ** | |
| 2714 ** These routines return the name assigned to a particular column | |
| 2715 ** in the result set of a [SELECT] statement. The sqlite3_column_name() | |
| 2716 ** interface returns a pointer to a zero-terminated UTF-8 string | |
| 2717 ** and sqlite3_column_name16() returns a pointer to a zero-terminated | |
| 2718 ** UTF-16 string. The first parameter is the [prepared statement] | |
| 2719 ** that implements the [SELECT] statement. The second parameter is the | |
| 2720 ** column number. The leftmost column is number 0. | |
| 2721 ** | |
| 2722 ** The returned string pointer is valid until either the [prepared statement] | |
| 2723 ** is destroyed by [sqlite3_finalize()] or until the next call to | |
| 2724 ** sqlite3_column_name() or sqlite3_column_name16() on the same column. | |
| 2725 ** | |
| 2726 ** If sqlite3_malloc() fails during the processing of either routine | |
| 2727 ** (for example during a conversion from UTF-8 to UTF-16) then a | |
| 2728 ** NULL pointer is returned. | |
| 2729 ** | |
| 2730 ** The name of a result column is the value of the "AS" clause for | |
| 2731 ** that column, if there is an AS clause. If there is no AS clause | |
| 2732 ** then the name of the column is unspecified and may change from | |
| 2733 ** one release of SQLite to the next. | |
| 2734 ** | |
| 2735 ** Requirements: | |
| 2736 ** [H13721] [H13723] [H13724] [H13725] [H13726] [H13727] | |
| 2737 */ | |
| 2738 SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N); | |
| 2739 SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N); | |
| 2740 | |
| 2741 /* | |
| 2742 ** CAPI3REF: Source Of Data In A Query Result {H13740} <S10700> | |
| 2743 ** | |
| 2744 ** These routines provide a means to determine what column of what | |
| 2745 ** table in which database a result of a [SELECT] statement comes from. | |
| 2746 ** The name of the database or table or column can be returned as | |
| 2747 ** either a UTF-8 or UTF-16 string. The _database_ routines return | |
| 2748 ** the database name, the _table_ routines return the table name, and | |
| 2749 ** the origin_ routines return the column name. | |
| 2750 ** The returned string is valid until the [prepared statement] is destroyed | |
| 2751 ** using [sqlite3_finalize()] or until the same information is requested | |
| 2752 ** again in a different encoding. | |
| 2753 ** | |
| 2754 ** The names returned are the original un-aliased names of the | |
| 2755 ** database, table, and column. | |
| 2756 ** | |
| 2757 ** The first argument to the following calls is a [prepared statement]. | |
| 2758 ** These functions return information about the Nth column returned by | |
| 2759 ** the statement, where N is the second function argument. | |
| 2760 ** | |
| 2761 ** If the Nth column returned by the statement is an expression or | |
| 2762 ** subquery and is not a column value, then all of these functions return | |
| 2763 ** NULL. These routine might also return NULL if a memory allocation error | |
| 2764 ** occurs. Otherwise, they return the name of the attached database, table | |
| 2765 ** and column that query result column was extracted from. | |
| 2766 ** | |
| 2767 ** As with all other SQLite APIs, those postfixed with "16" return | |
| 2768 ** UTF-16 encoded strings, the other functions return UTF-8. {END} | |
| 2769 ** | |
| 2770 ** These APIs are only available if the library was compiled with the | |
| 2771 ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined. | |
| 2772 ** | |
| 2773 ** {A13751} | |
| 2774 ** If two or more threads call one or more of these routines against the same | |
| 2775 ** prepared statement and column at the same time then the results are | |
| 2776 ** undefined. | |
| 2777 ** | |
| 2778 ** Requirements: | |
| 2779 ** [H13741] [H13742] [H13743] [H13744] [H13745] [H13746] [H13748] | |
| 2780 ** | |
| 2781 ** If two or more threads call one or more | |
| 2782 ** [sqlite3_column_database_name | column metadata interfaces] | |
| 2783 ** for the same [prepared statement] and result column | |
| 2784 ** at the same time then the results are undefined. | |
| 2785 */ | |
| 2786 SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int); | |
| 2787 SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int); | |
| 2788 SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int); | |
| 2789 SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int); | |
| 2790 SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int); | |
| 2791 SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int); | |
| 2792 | |
| 2793 /* | |
| 2794 ** CAPI3REF: Declared Datatype Of A Query Result {H13760} <S10700> | |
| 2795 ** | |
| 2796 ** The first parameter is a [prepared statement]. | |
| 2797 ** If this statement is a [SELECT] statement and the Nth column of the | |
| 2798 ** returned result set of that [SELECT] is a table column (not an | |
| 2799 ** expression or subquery) then the declared type of the table | |
| 2800 ** column is returned. If the Nth column of the result set is an | |
| 2801 ** expression or subquery, then a NULL pointer is returned. | |
| 2802 ** The returned string is always UTF-8 encoded. {END} | |
| 2803 ** | |
| 2804 ** For example, given the database schema: | |
| 2805 ** | |
| 2806 ** CREATE TABLE t1(c1 VARIANT); | |
| 2807 ** | |
| 2808 ** and the following statement to be compiled: | |
| 2809 ** | |
| 2810 ** SELECT c1 + 1, c1 FROM t1; | |
| 2811 ** | |
| 2812 ** this routine would return the string "VARIANT" for the second result | |
| 2813 ** column (i==1), and a NULL pointer for the first result column (i==0). | |
| 2814 ** | |
| 2815 ** SQLite uses dynamic run-time typing. So just because a column | |
| 2816 ** is declared to contain a particular type does not mean that the | |
| 2817 ** data stored in that column is of the declared type. SQLite is | |
| 2818 ** strongly typed, but the typing is dynamic not static. Type | |
| 2819 ** is associated with individual values, not with the containers | |
| 2820 ** used to hold those values. | |
| 2821 ** | |
| 2822 ** Requirements: | |
| 2823 ** [H13761] [H13762] [H13763] | |
| 2824 */ | |
| 2825 SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int); | |
| 2826 SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int); | |
| 2827 | |
| 2828 /* | |
| 2829 ** CAPI3REF: Evaluate An SQL Statement {H13200} <S10000> | |
| 2830 ** | |
| 2831 ** After a [prepared statement] has been prepared using either | |
| 2832 ** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy | |
| 2833 ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function | |
| 2834 ** must be called one or more times to evaluate the statement. | |
| 2835 ** | |
| 2836 ** The details of the behavior of the sqlite3_step() interface depend | |
| 2837 ** on whether the statement was prepared using the newer "v2" interface | |
| 2838 ** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy | |
| 2839 ** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the | |
| 2840 ** new "v2" interface is recommended for new applications but the legacy | |
| 2841 ** interface will continue to be supported. | |
| 2842 ** | |
| 2843 ** In the legacy interface, the return value will be either [SQLITE_BUSY], | |
| 2844 ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. | |
| 2845 ** With the "v2" interface, any of the other [result codes] or | |
| 2846 ** [extended result codes] might be returned as well. | |
| 2847 ** | |
| 2848 ** [SQLITE_BUSY] means that the database engine was unable to acquire the | |
| 2849 ** database locks it needs to do its job. If the statement is a [COMMIT] | |
| 2850 ** or occurs outside of an explicit transaction, then you can retry the | |
| 2851 ** statement. If the statement is not a [COMMIT] and occurs within a | |
| 2852 ** explicit transaction then you should rollback the transaction before | |
| 2853 ** continuing. | |
| 2854 ** | |
| 2855 ** [SQLITE_DONE] means that the statement has finished executing | |
| 2856 ** successfully. sqlite3_step() should not be called again on this virtual | |
| 2857 ** machine without first calling [sqlite3_reset()] to reset the virtual | |
| 2858 ** machine back to its initial state. | |
| 2859 ** | |
| 2860 ** If the SQL statement being executed returns any data, then [SQLITE_ROW] | |
| 2861 ** is returned each time a new row of data is ready for processing by the | |
| 2862 ** caller. The values may be accessed using the [column access functions]. | |
| 2863 ** sqlite3_step() is called again to retrieve the next row of data. | |
| 2864 ** | |
| 2865 ** [SQLITE_ERROR] means that a run-time error (such as a constraint | |
| 2866 ** violation) has occurred. sqlite3_step() should not be called again on | |
| 2867 ** the VM. More information may be found by calling [sqlite3_errmsg()]. | |
| 2868 ** With the legacy interface, a more specific error code (for example, | |
| 2869 ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) | |
| 2870 ** can be obtained by calling [sqlite3_reset()] on the | |
| 2871 ** [prepared statement]. In the "v2" interface, | |
| 2872 ** the more specific error code is returned directly by sqlite3_step(). | |
| 2873 ** | |
| 2874 ** [SQLITE_MISUSE] means that the this routine was called inappropriately. | |
| 2875 ** Perhaps it was called on a [prepared statement] that has | |
| 2876 ** already been [sqlite3_finalize | finalized] or on one that had | |
| 2877 ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could | |
| 2878 ** be the case that the same database connection is being used by two or | |
| 2879 ** more threads at the same moment in time. | |
| 2880 ** | |
| 2881 ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step() | |
| 2882 ** API always returns a generic error code, [SQLITE_ERROR], following any | |
| 2883 ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call | |
| 2884 ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the | |
| 2885 ** specific [error codes] that better describes the error. | |
| 2886 ** We admit that this is a goofy design. The problem has been fixed | |
| 2887 ** with the "v2" interface. If you prepare all of your SQL statements | |
| 2888 ** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead | |
| 2889 ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces, | |
| 2890 ** then the more specific [error codes] are returned directly | |
| 2891 ** by sqlite3_step(). The use of the "v2" interface is recommended. | |
| 2892 ** | |
| 2893 ** Requirements: | |
| 2894 ** [H13202] [H15304] [H15306] [H15308] [H15310] | |
| 2895 */ | |
| 2896 SQLITE_API int sqlite3_step(sqlite3_stmt*); | |
| 2897 | |
| 2898 /* | |
| 2899 ** CAPI3REF: Number of columns in a result set {H13770} <S10700> | |
| 2900 ** | |
| 2901 ** Returns the number of values in the current row of the result set. | |
| 2902 ** | |
| 2903 ** Requirements: | |
| 2904 ** [H13771] [H13772] | |
| 2905 */ | |
| 2906 SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt); | |
| 2907 | |
| 2908 /* | |
| 2909 ** CAPI3REF: Fundamental Datatypes {H10265} <S10110><S10120> | |
| 2910 ** KEYWORDS: SQLITE_TEXT | |
| 2911 ** | |
| 2912 ** {H10266} Every value in SQLite has one of five fundamental datatypes: | |
| 2913 ** | |
| 2914 ** <ul> | |
| 2915 ** <li> 64-bit signed integer | |
| 2916 ** <li> 64-bit IEEE floating point number | |
| 2917 ** <li> string | |
| 2918 ** <li> BLOB | |
| 2919 ** <li> NULL | |
| 2920 ** </ul> {END} | |
| 2921 ** | |
| 2922 ** These constants are codes for each of those types. | |
| 2923 ** | |
| 2924 ** Note that the SQLITE_TEXT constant was also used in SQLite version 2 | |
| 2925 ** for a completely different meaning. Software that links against both | |
| 2926 ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not | |
| 2927 ** SQLITE_TEXT. | |
| 2928 */ | |
| 2929 #define SQLITE_INTEGER 1 | |
| 2930 #define SQLITE_FLOAT 2 | |
| 2931 #define SQLITE_BLOB 4 | |
| 2932 #define SQLITE_NULL 5 | |
| 2933 #ifdef SQLITE_TEXT | |
| 2934 # undef SQLITE_TEXT | |
| 2935 #else | |
| 2936 # define SQLITE_TEXT 3 | |
| 2937 #endif | |
| 2938 #define SQLITE3_TEXT 3 | |
| 2939 | |
| 2940 /* | |
| 2941 ** CAPI3REF: Result Values From A Query {H13800} <S10700> | |
| 2942 ** KEYWORDS: {column access functions} | |
| 2943 ** | |
| 2944 ** These routines form the "result set query" interface. | |
| 2945 ** | |
| 2946 ** These routines return information about a single column of the current | |
| 2947 ** result row of a query. In every case the first argument is a pointer | |
| 2948 ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*] | |
| 2949 ** that was returned from [sqlite3_prepare_v2()] or one of its variants) | |
| 2950 ** and the second argument is the index of the column for which information | |
| 2951 ** should be returned. The leftmost column of the result set has the index 0. | |
| 2952 ** | |
| 2953 ** If the SQL statement does not currently point to a valid row, or if the | |
| 2954 ** column index is out of range, the result is undefined. | |
| 2955 ** These routines may only be called when the most recent call to | |
| 2956 ** [sqlite3_step()] has returned [SQLITE_ROW] and neither | |
| 2957 ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently. | |
| 2958 ** If any of these routines are called after [sqlite3_reset()] or | |
| 2959 ** [sqlite3_finalize()] or after [sqlite3_step()] has returned | |
| 2960 ** something other than [SQLITE_ROW], the results are undefined. | |
| 2961 ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] | |
| 2962 ** are called from a different thread while any of these routines | |
| 2963 ** are pending, then the results are undefined. | |
| 2964 ** | |
| 2965 ** The sqlite3_column_type() routine returns the | |
| 2966 ** [SQLITE_INTEGER | datatype code] for the initial data type | |
| 2967 ** of the result column. The returned value is one of [SQLITE_INTEGER], | |
| 2968 ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value | |
| 2969 ** returned by sqlite3_column_type() is only meaningful if no type | |
| 2970 ** conversions have occurred as described below. After a type conversion, | |
| 2971 ** the value returned by sqlite3_column_type() is undefined. Future | |
| 2972 ** versions of SQLite may change the behavior of sqlite3_column_type() | |
| 2973 ** following a type conversion. | |
| 2974 ** | |
| 2975 ** If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() | |
| 2976 ** routine returns the number of bytes in that BLOB or string. | |
| 2977 ** If the result is a UTF-16 string, then sqlite3_column_bytes() converts | |
| 2978 ** the string to UTF-8 and then returns the number of bytes. | |
| 2979 ** If the result is a numeric value then sqlite3_column_bytes() uses | |
| 2980 ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns | |
| 2981 ** the number of bytes in that string. | |
| 2982 ** The value returned does not include the zero terminator at the end | |
| 2983 ** of the string. For clarity: the value returned is the number of | |
| 2984 ** bytes in the string, not the number of characters. | |
| 2985 ** | |
| 2986 ** Strings returned by sqlite3_column_text() and sqlite3_column_text16(), | |
| 2987 ** even empty strings, are always zero terminated. The return | |
| 2988 ** value from sqlite3_column_blob() for a zero-length BLOB is an arbitrary | |
| 2989 ** pointer, possibly even a NULL pointer. | |
| 2990 ** | |
| 2991 ** The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes() | |
| 2992 ** but leaves the result in UTF-16 in native byte order instead of UTF-8. | |
| 2993 ** The zero terminator is not included in this count. | |
| 2994 ** | |
| 2995 ** The object returned by [sqlite3_column_value()] is an | |
| 2996 ** [unprotected sqlite3_value] object. An unprotected sqlite3_value object | |
| 2997 ** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()]. | |
| 2998 ** If the [unprotected sqlite3_value] object returned by | |
| 2999 ** [sqlite3_column_value()] is used in any other way, including calls | |
| 3000 ** to routines like [sqlite3_value_int()], [sqlite3_value_text()], | |
| 3001 ** or [sqlite3_value_bytes()], then the behavior is undefined. | |
| 3002 ** | |
| 3003 ** These routines attempt to convert the value where appropriate. For | |
| 3004 ** example, if the internal representation is FLOAT and a text result | |
| 3005 ** is requested, [sqlite3_snprintf()] is used internally to perform the | |
| 3006 ** conversion automatically. The following table details the conversions | |
| 3007 ** that are applied: | |
| 3008 ** | |
| 3009 ** <blockquote> | |
| 3010 ** <table border="1"> | |
| 3011 ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion | |
| 3012 ** | |
| 3013 ** <tr><td> NULL <td> INTEGER <td> Result is 0 | |
| 3014 ** <tr><td> NULL <td> FLOAT <td> Result is 0.0 | |
| 3015 ** <tr><td> NULL <td> TEXT <td> Result is NULL pointer | |
| 3016 ** <tr><td> NULL <td> BLOB <td> Result is NULL pointer | |
| 3017 ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float | |
| 3018 ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer | |
| 3019 ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT | |
| 3020 ** <tr><td> FLOAT <td> INTEGER <td> Convert from float to integer | |
| 3021 ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float | |
| 3022 ** <tr><td> FLOAT <td> BLOB <td> Same as FLOAT->TEXT | |
| 3023 ** <tr><td> TEXT <td> INTEGER <td> Use atoi() | |
| 3024 ** <tr><td> TEXT <td> FLOAT <td> Use atof() | |
| 3025 ** <tr><td> TEXT <td> BLOB <td> No change | |
| 3026 ** <tr><td> BLOB <td> INTEGER <td> Convert to TEXT then use atoi() | |
| 3027 ** <tr><td> BLOB <td> FLOAT <td> Convert to TEXT then use atof() | |
| 3028 ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed | |
| 3029 ** </table> | |
| 3030 ** </blockquote> | |
| 3031 ** | |
| 3032 ** The table above makes reference to standard C library functions atoi() | |
| 3033 ** and atof(). SQLite does not really use these functions. It has its | |
| 3034 ** own equivalent internal routines. The atoi() and atof() names are | |
| 3035 ** used in the table for brevity and because they are familiar to most | |
| 3036 ** C programmers. | |
| 3037 ** | |
| 3038 ** Note that when type conversions occur, pointers returned by prior | |
| 3039 ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or | |
| 3040 ** sqlite3_column_text16() may be invalidated. | |
| 3041 ** Type conversions and pointer invalidations might occur | |
| 3042 ** in the following cases: | |
| 3043 ** | |
| 3044 ** <ul> | |
| 3045 ** <li> The initial content is a BLOB and sqlite3_column_text() or | |
| 3046 ** sqlite3_column_text16() is called. A zero-terminator might | |
| 3047 ** need to be added to the string.</li> | |
| 3048 ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or | |
| 3049 ** sqlite3_column_text16() is called. The content must be converted | |
| 3050 ** to UTF-16.</li> | |
| 3051 ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or | |
| 3052 ** sqlite3_column_text() is called. The content must be converted | |
| 3053 ** to UTF-8.</li> | |
| 3054 ** </ul> | |
| 3055 ** | |
| 3056 ** Conversions between UTF-16be and UTF-16le are always done in place and do | |
| 3057 ** not invalidate a prior pointer, though of course the content of the buffer | |
| 3058 ** that the prior pointer points to will have been modified. Other kinds | |
| 3059 ** of conversion are done in place when it is possible, but sometimes they | |
| 3060 ** are not possible and in those cases prior pointers are invalidated. | |
| 3061 ** | |
| 3062 ** The safest and easiest to remember policy is to invoke these routines | |
| 3063 ** in one of the following ways: | |
| 3064 ** | |
| 3065 ** <ul> | |
| 3066 ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li> | |
| 3067 ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li> | |
| 3068 ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li> | |
| 3069 ** </ul> | |
| 3070 ** | |
| 3071 ** In other words, you should call sqlite3_column_text(), | |
| 3072 ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result | |
| 3073 ** into the desired format, then invoke sqlite3_column_bytes() or | |
| 3074 ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls | |
| 3075 ** to sqlite3_column_text() or sqlite3_column_blob() with calls to | |
| 3076 ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16() | |
| 3077 ** with calls to sqlite3_column_bytes(). | |
| 3078 ** | |
| 3079 ** The pointers returned are valid until a type conversion occurs as | |
| 3080 ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or | |
| 3081 ** [sqlite3_finalize()] is called. The memory space used to hold strings | |
| 3082 ** and BLOBs is freed automatically. Do <b>not</b> pass the pointers returned | |
| 3083 ** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into | |
| 3084 ** [sqlite3_free()]. | |
| 3085 ** | |
| 3086 ** If a memory allocation error occurs during the evaluation of any | |
| 3087 ** of these routines, a default value is returned. The default value | |
| 3088 ** is either the integer 0, the floating point number 0.0, or a NULL | |
| 3089 ** pointer. Subsequent calls to [sqlite3_errcode()] will return | |
| 3090 ** [SQLITE_NOMEM]. | |
| 3091 ** | |
| 3092 ** Requirements: | |
| 3093 ** [H13803] [H13806] [H13809] [H13812] [H13815] [H13818] [H13821] [H13824] | |
| 3094 ** [H13827] [H13830] | |
| 3095 */ | |
| 3096 SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); | |
| 3097 SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol); | |
| 3098 SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol); | |
| 3099 SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol); | |
| 3100 SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol); | |
| 3101 SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); | |
| 3102 SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol); | |
| 3103 SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol); | |
| 3104 SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol); | |
| 3105 SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol); | |
| 3106 | |
| 3107 /* | |
| 3108 ** CAPI3REF: Destroy A Prepared Statement Object {H13300} <S70300><S30100> | |
| 3109 ** | |
| 3110 ** The sqlite3_finalize() function is called to delete a [prepared statement]. | |
| 3111 ** If the statement was executed successfully or not executed at all, then | |
| 3112 ** SQLITE_OK is returned. If execution of the statement failed then an | |
| 3113 ** [error code] or [extended error code] is returned. | |
| 3114 ** | |
| 3115 ** This routine can be called at any point during the execution of the | |
| 3116 ** [prepared statement]. If the virtual machine has not | |
| 3117 ** completed execution when this routine is called, that is like | |
| 3118 ** encountering an error or an [sqlite3_interrupt | interrupt]. | |
| 3119 ** Incomplete updates may be rolled back and transactions canceled, | |
| 3120 ** depending on the circumstances, and the | |
| 3121 ** [error code] returned will be [SQLITE_ABORT]. | |
| 3122 ** | |
| 3123 ** Requirements: | |
| 3124 ** [H11302] [H11304] | |
| 3125 */ | |
| 3126 SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt); | |
| 3127 | |
| 3128 /* | |
| 3129 ** CAPI3REF: Reset A Prepared Statement Object {H13330} <S70300> | |
| 3130 ** | |
| 3131 ** The sqlite3_reset() function is called to reset a [prepared statement] | |
| 3132 ** object back to its initial state, ready to be re-executed. | |
| 3133 ** Any SQL statement variables that had values bound to them using | |
| 3134 ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. | |
| 3135 ** Use [sqlite3_clear_bindings()] to reset the bindings. | |
| 3136 ** | |
| 3137 ** {H11332} The [sqlite3_reset(S)] interface resets the [prepared statement] S | |
| 3138 ** back to the beginning of its program. | |
| 3139 ** | |
| 3140 ** {H11334} If the most recent call to [sqlite3_step(S)] for the | |
| 3141 ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE], | |
| 3142 ** or if [sqlite3_step(S)] has never before been called on S, | |
| 3143 ** then [sqlite3_reset(S)] returns [SQLITE_OK]. | |
| 3144 ** | |
| 3145 ** {H11336} If the most recent call to [sqlite3_step(S)] for the | |
| 3146 ** [prepared statement] S indicated an error, then | |
| 3147 ** [sqlite3_reset(S)] returns an appropriate [error code]. | |
| 3148 ** | |
| 3149 ** {H11338} The [sqlite3_reset(S)] interface does not change the values | |
| 3150 ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S. | |
| 3151 */ | |
| 3152 SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt); | |
| 3153 | |
| 3154 /* | |
| 3155 ** CAPI3REF: Create Or Redefine SQL Functions {H16100} <S20200> | |
| 3156 ** KEYWORDS: {function creation routines} | |
| 3157 ** KEYWORDS: {application-defined SQL function} | |
| 3158 ** KEYWORDS: {application-defined SQL functions} | |
| 3159 ** | |
| 3160 ** These two functions (collectively known as "function creation routines") | |
| 3161 ** are used to add SQL functions or aggregates or to redefine the behavior | |
| 3162 ** of existing SQL functions or aggregates. The only difference between the | |
| 3163 ** two is that the second parameter, the name of the (scalar) function or | |
| 3164 ** aggregate, is encoded in UTF-8 for sqlite3_create_function() and UTF-16 | |
| 3165 ** for sqlite3_create_function16(). | |
| 3166 ** | |
| 3167 ** The first parameter is the [database connection] to which the SQL | |
| 3168 ** function is to be added. If a single program uses more than one database | |
| 3169 ** connection internally, then SQL functions must be added individually to | |
| 3170 ** each database connection. | |
| 3171 ** | |
| 3172 ** The second parameter is the name of the SQL function to be created or | |
| 3173 ** redefined. The length of the name is limited to 255 bytes, exclusive of | |
| 3174 ** the zero-terminator. Note that the name length limit is in bytes, not | |
| 3175 ** characters. Any attempt to create a function with a longer name | |
| 3176 ** will result in [SQLITE_ERROR] being returned. | |
| 3177 ** | |
| 3178 ** The third parameter (nArg) | |
| 3179 ** is the number of arguments that the SQL function or | |
| 3180 ** aggregate takes. If this parameter is -1, then the SQL function or | |
| 3181 ** aggregate may take any number of arguments between 0 and the limit | |
| 3182 ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third | |
| 3183 ** parameter is less than -1 or greater than 127 then the behavior is | |
| 3184 ** undefined. | |
| 3185 ** | |
| 3186 ** The fourth parameter, eTextRep, specifies what | |
| 3187 ** [SQLITE_UTF8 | text encoding] this SQL function prefers for | |
| 3188 ** its parameters. Any SQL function implementation should be able to work | |
| 3189 ** work with UTF-8, UTF-16le, or UTF-16be. But some implementations may be | |
| 3190 ** more efficient with one encoding than another. An application may | |
| 3191 ** invoke sqlite3_create_function() or sqlite3_create_function16() multiple | |
| 3192 ** times with the same function but with different values of eTextRep. | |
| 3193 ** When multiple implementations of the same function are available, SQLite | |
| 3194 ** will pick the one that involves the least amount of data conversion. | |
| 3195 ** If there is only a single implementation which does not care what text | |
| 3196 ** encoding is used, then the fourth argument should be [SQLITE_ANY]. | |
| 3197 ** | |
| 3198 ** The fifth parameter is an arbitrary pointer. The implementation of the | |
| 3199 ** function can gain access to this pointer using [sqlite3_user_data()]. | |
| 3200 ** | |
| 3201 ** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are | |
| 3202 ** pointers to C-language functions that implement the SQL function or | |
| 3203 ** aggregate. A scalar SQL function requires an implementation of the xFunc | |
| 3204 ** callback only, NULL pointers should be passed as the xStep and xFinal | |
| 3205 ** parameters. An aggregate SQL function requires an implementation of xStep | |
| 3206 ** and xFinal and NULL should be passed for xFunc. To delete an existing | |
| 3207 ** SQL function or aggregate, pass NULL for all three function callbacks. | |
| 3208 ** | |
| 3209 ** It is permitted to register multiple implementations of the same | |
| 3210 ** functions with the same name but with either differing numbers of | |
| 3211 ** arguments or differing preferred text encodings. SQLite will use | |
| 3212 ** the implementation that most closely matches the way in which the | |
| 3213 ** SQL function is used. A function implementation with a non-negative | |
| 3214 ** nArg parameter is a better match than a function implementation with | |
| 3215 ** a negative nArg. A function where the preferred text encoding | |
| 3216 ** matches the database encoding is a better | |
| 3217 ** match than a function where the encoding is different. | |
| 3218 ** A function where the encoding difference is between UTF16le and UTF16be | |
| 3219 ** is a closer match than a function where the encoding difference is | |
| 3220 ** between UTF8 and UTF16. | |
| 3221 ** | |
| 3222 ** Built-in functions may be overloaded by new application-defined functions. | |
| 3223 ** The first application-defined function with a given name overrides all | |
| 3224 ** built-in functions in the same [database connection] with the same name. | |
| 3225 ** Subsequent application-defined functions of the same name only override | |
| 3226 ** prior application-defined functions that are an exact match for the | |
| 3227 ** number of parameters and preferred encoding. | |
| 3228 ** | |
| 3229 ** An application-defined function is permitted to call other | |
| 3230 ** SQLite interfaces. However, such calls must not | |
| 3231 ** close the database connection nor finalize or reset the prepared | |
| 3232 ** statement in which the function is running. | |
| 3233 ** | |
| 3234 ** Requirements: | |
| 3235 ** [H16103] [H16106] [H16109] [H16112] [H16118] [H16121] [H16127] | |
| 3236 ** [H16130] [H16133] [H16136] [H16139] [H16142] | |
| 3237 */ | |
| 3238 SQLITE_API int sqlite3_create_function( | |
| 3239 sqlite3 *db, | |
| 3240 const char *zFunctionName, | |
| 3241 int nArg, | |
| 3242 int eTextRep, | |
| 3243 void *pApp, | |
| 3244 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), | |
| 3245 void (*xStep)(sqlite3_context*,int,sqlite3_value**), | |
| 3246 void (*xFinal)(sqlite3_context*) | |
| 3247 ); | |
| 3248 SQLITE_API int sqlite3_create_function16( | |
| 3249 sqlite3 *db, | |
| 3250 const void *zFunctionName, | |
| 3251 int nArg, | |
| 3252 int eTextRep, | |
| 3253 void *pApp, | |
| 3254 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), | |
| 3255 void (*xStep)(sqlite3_context*,int,sqlite3_value**), | |
| 3256 void (*xFinal)(sqlite3_context*) | |
| 3257 ); | |
| 3258 | |
| 3259 /* | |
| 3260 ** CAPI3REF: Text Encodings {H10267} <S50200> <H16100> | |
| 3261 ** | |
| 3262 ** These constant define integer codes that represent the various | |
| 3263 ** text encodings supported by SQLite. | |
| 3264 */ | |
| 3265 #define SQLITE_UTF8 1 | |
| 3266 #define SQLITE_UTF16LE 2 | |
| 3267 #define SQLITE_UTF16BE 3 | |
| 3268 #define SQLITE_UTF16 4 /* Use native byte order */ | |
| 3269 #define SQLITE_ANY 5 /* sqlite3_create_function only */ | |
| 3270 #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ | |
| 3271 | |
| 3272 /* | |
| 3273 ** CAPI3REF: Deprecated Functions | |
| 3274 ** DEPRECATED | |
| 3275 ** | |
| 3276 ** These functions are [deprecated]. In order to maintain | |
| 3277 ** backwards compatibility with older code, these functions continue | |
| 3278 ** to be supported. However, new applications should avoid | |
| 3279 ** the use of these functions. To help encourage people to avoid | |
| 3280 ** using these functions, we are not going to tell you what they do. | |
| 3281 */ | |
| 3282 #ifndef SQLITE_OMIT_DEPRECATED | |
| 3283 SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*); | |
| 3284 SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*); | |
| 3285 SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite
3_stmt*); | |
| 3286 SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void); | |
| 3287 SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void); | |
| 3288 SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int6
4,int),void*,sqlite3_int64); | |
| 3289 #endif | |
| 3290 | |
| 3291 /* | |
| 3292 ** CAPI3REF: Obtaining SQL Function Parameter Values {H15100} <S20200> | |
| 3293 ** | |
| 3294 ** The C-language implementation of SQL functions and aggregates uses | |
| 3295 ** this set of interface routines to access the parameter values on | |
| 3296 ** the function or aggregate. | |
| 3297 ** | |
| 3298 ** The xFunc (for scalar functions) or xStep (for aggregates) parameters | |
| 3299 ** to [sqlite3_create_function()] and [sqlite3_create_function16()] | |
| 3300 ** define callbacks that implement the SQL functions and aggregates. | |
| 3301 ** The 4th parameter to these callbacks is an array of pointers to | |
| 3302 ** [protected sqlite3_value] objects. There is one [sqlite3_value] object for | |
| 3303 ** each parameter to the SQL function. These routines are used to | |
| 3304 ** extract values from the [sqlite3_value] objects. | |
| 3305 ** | |
| 3306 ** These routines work only with [protected sqlite3_value] objects. | |
| 3307 ** Any attempt to use these routines on an [unprotected sqlite3_value] | |
| 3308 ** object results in undefined behavior. | |
| 3309 ** | |
| 3310 ** These routines work just like the corresponding [column access functions] | |
| 3311 ** except that these routines take a single [protected sqlite3_value] object | |
| 3312 ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number. | |
| 3313 ** | |
| 3314 ** The sqlite3_value_text16() interface extracts a UTF-16 string | |
| 3315 ** in the native byte-order of the host machine. The | |
| 3316 ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces | |
| 3317 ** extract UTF-16 strings as big-endian and little-endian respectively. | |
| 3318 ** | |
| 3319 ** The sqlite3_value_numeric_type() interface attempts to apply | |
| 3320 ** numeric affinity to the value. This means that an attempt is | |
| 3321 ** made to convert the value to an integer or floating point. If | |
| 3322 ** such a conversion is possible without loss of information (in other | |
| 3323 ** words, if the value is a string that looks like a number) | |
| 3324 ** then the conversion is performed. Otherwise no conversion occurs. | |
| 3325 ** The [SQLITE_INTEGER | datatype] after conversion is returned. | |
| 3326 ** | |
| 3327 ** Please pay particular attention to the fact that the pointer returned | |
| 3328 ** from [sqlite3_value_blob()], [sqlite3_value_text()], or | |
| 3329 ** [sqlite3_value_text16()] can be invalidated by a subsequent call to | |
| 3330 ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], | |
| 3331 ** or [sqlite3_value_text16()]. | |
| 3332 ** | |
| 3333 ** These routines must be called from the same thread as | |
| 3334 ** the SQL function that supplied the [sqlite3_value*] parameters. | |
| 3335 ** | |
| 3336 ** Requirements: | |
| 3337 ** [H15103] [H15106] [H15109] [H15112] [H15115] [H15118] [H15121] [H15124] | |
| 3338 ** [H15127] [H15130] [H15133] [H15136] | |
| 3339 */ | |
| 3340 SQLITE_API const void *sqlite3_value_blob(sqlite3_value*); | |
| 3341 SQLITE_API int sqlite3_value_bytes(sqlite3_value*); | |
| 3342 SQLITE_API int sqlite3_value_bytes16(sqlite3_value*); | |
| 3343 SQLITE_API double sqlite3_value_double(sqlite3_value*); | |
| 3344 SQLITE_API int sqlite3_value_int(sqlite3_value*); | |
| 3345 SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*); | |
| 3346 SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*); | |
| 3347 SQLITE_API const void *sqlite3_value_text16(sqlite3_value*); | |
| 3348 SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*); | |
| 3349 SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*); | |
| 3350 SQLITE_API int sqlite3_value_type(sqlite3_value*); | |
| 3351 SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*); | |
| 3352 | |
| 3353 /* | |
| 3354 ** CAPI3REF: Obtain Aggregate Function Context {H16210} <S20200> | |
| 3355 ** | |
| 3356 ** The implementation of aggregate SQL functions use this routine to allocate | |
| 3357 ** a structure for storing their state. | |
| 3358 ** | |
| 3359 ** The first time the sqlite3_aggregate_context() routine is called for a | |
| 3360 ** particular aggregate, SQLite allocates nBytes of memory, zeroes out that | |
| 3361 ** memory, and returns a pointer to it. On second and subsequent calls to | |
| 3362 ** sqlite3_aggregate_context() for the same aggregate function index, | |
| 3363 ** the same buffer is returned. The implementation of the aggregate can use | |
| 3364 ** the returned buffer to accumulate data. | |
| 3365 ** | |
| 3366 ** SQLite automatically frees the allocated buffer when the aggregate | |
| 3367 ** query concludes. | |
| 3368 ** | |
| 3369 ** The first parameter should be a copy of the | |
| 3370 ** [sqlite3_context | SQL function context] that is the first parameter | |
| 3371 ** to the callback routine that implements the aggregate function. | |
| 3372 ** | |
| 3373 ** This routine must be called from the same thread in which | |
| 3374 ** the aggregate SQL function is running. | |
| 3375 ** | |
| 3376 ** Requirements: | |
| 3377 ** [H16211] [H16213] [H16215] [H16217] | |
| 3378 */ | |
| 3379 SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); | |
| 3380 | |
| 3381 /* | |
| 3382 ** CAPI3REF: User Data For Functions {H16240} <S20200> | |
| 3383 ** | |
| 3384 ** The sqlite3_user_data() interface returns a copy of | |
| 3385 ** the pointer that was the pUserData parameter (the 5th parameter) | |
| 3386 ** of the [sqlite3_create_function()] | |
| 3387 ** and [sqlite3_create_function16()] routines that originally | |
| 3388 ** registered the application defined function. {END} | |
| 3389 ** | |
| 3390 ** This routine must be called from the same thread in which | |
| 3391 ** the application-defined function is running. | |
| 3392 ** | |
| 3393 ** Requirements: | |
| 3394 ** [H16243] | |
| 3395 */ | |
| 3396 SQLITE_API void *sqlite3_user_data(sqlite3_context*); | |
| 3397 | |
| 3398 /* | |
| 3399 ** CAPI3REF: Database Connection For Functions {H16250} <S60600><S20200> | |
| 3400 ** | |
| 3401 ** The sqlite3_context_db_handle() interface returns a copy of | |
| 3402 ** the pointer to the [database connection] (the 1st parameter) | |
| 3403 ** of the [sqlite3_create_function()] | |
| 3404 ** and [sqlite3_create_function16()] routines that originally | |
| 3405 ** registered the application defined function. | |
| 3406 ** | |
| 3407 ** Requirements: | |
| 3408 ** [H16253] | |
| 3409 */ | |
| 3410 SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*); | |
| 3411 | |
| 3412 /* | |
| 3413 ** CAPI3REF: Function Auxiliary Data {H16270} <S20200> | |
| 3414 ** | |
| 3415 ** The following two functions may be used by scalar SQL functions to | |
| 3416 ** associate metadata with argument values. If the same value is passed to | |
| 3417 ** multiple invocations of the same SQL function during query execution, under | |
| 3418 ** some circumstances the associated metadata may be preserved. This may | |
| 3419 ** be used, for example, to add a regular-expression matching scalar | |
| 3420 ** function. The compiled version of the regular expression is stored as | |
| 3421 ** metadata associated with the SQL value passed as the regular expression | |
| 3422 ** pattern. The compiled regular expression can be reused on multiple | |
| 3423 ** invocations of the same function so that the original pattern string | |
| 3424 ** does not need to be recompiled on each invocation. | |
| 3425 ** | |
| 3426 ** The sqlite3_get_auxdata() interface returns a pointer to the metadata | |
| 3427 ** associated by the sqlite3_set_auxdata() function with the Nth argument | |
| 3428 ** value to the application-defined function. If no metadata has been ever | |
| 3429 ** been set for the Nth argument of the function, or if the corresponding | |
| 3430 ** function parameter has changed since the meta-data was set, | |
| 3431 ** then sqlite3_get_auxdata() returns a NULL pointer. | |
| 3432 ** | |
| 3433 ** The sqlite3_set_auxdata() interface saves the metadata | |
| 3434 ** pointed to by its 3rd parameter as the metadata for the N-th | |
| 3435 ** argument of the application-defined function. Subsequent | |
| 3436 ** calls to sqlite3_get_auxdata() might return this data, if it has | |
| 3437 ** not been destroyed. | |
| 3438 ** If it is not NULL, SQLite will invoke the destructor | |
| 3439 ** function given by the 4th parameter to sqlite3_set_auxdata() on | |
| 3440 ** the metadata when the corresponding function parameter changes | |
| 3441 ** or when the SQL statement completes, whichever comes first. | |
| 3442 ** | |
| 3443 ** SQLite is free to call the destructor and drop metadata on any | |
| 3444 ** parameter of any function at any time. The only guarantee is that | |
| 3445 ** the destructor will be called before the metadata is dropped. | |
| 3446 ** | |
| 3447 ** In practice, metadata is preserved between function calls for | |
| 3448 ** expressions that are constant at compile time. This includes literal | |
| 3449 ** values and SQL variables. | |
| 3450 ** | |
| 3451 ** These routines must be called from the same thread in which | |
| 3452 ** the SQL function is running. | |
| 3453 ** | |
| 3454 ** Requirements: | |
| 3455 ** [H16272] [H16274] [H16276] [H16277] [H16278] [H16279] | |
| 3456 */ | |
| 3457 SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N); | |
| 3458 SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(voi
d*)); | |
| 3459 | |
| 3460 | |
| 3461 /* | |
| 3462 ** CAPI3REF: Constants Defining Special Destructor Behavior {H10280} <S30100> | |
| 3463 ** | |
| 3464 ** These are special values for the destructor that is passed in as the | |
| 3465 ** final argument to routines like [sqlite3_result_blob()]. If the destructor | |
| 3466 ** argument is SQLITE_STATIC, it means that the content pointer is constant | |
| 3467 ** and will never change. It does not need to be destroyed. The | |
| 3468 ** SQLITE_TRANSIENT value means that the content will likely change in | |
| 3469 ** the near future and that SQLite should make its own private copy of | |
| 3470 ** the content before returning. | |
| 3471 ** | |
| 3472 ** The typedef is necessary to work around problems in certain | |
| 3473 ** C++ compilers. See ticket #2191. | |
| 3474 */ | |
| 3475 typedef void (*sqlite3_destructor_type)(void*); | |
| 3476 #define SQLITE_STATIC ((sqlite3_destructor_type)0) | |
| 3477 #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) | |
| 3478 | |
| 3479 /* | |
| 3480 ** CAPI3REF: Setting The Result Of An SQL Function {H16400} <S20200> | |
| 3481 ** | |
| 3482 ** These routines are used by the xFunc or xFinal callbacks that | |
| 3483 ** implement SQL functions and aggregates. See | |
| 3484 ** [sqlite3_create_function()] and [sqlite3_create_function16()] | |
| 3485 ** for additional information. | |
| 3486 ** | |
| 3487 ** These functions work very much like the [parameter binding] family of | |
| 3488 ** functions used to bind values to host parameters in prepared statements. | |
| 3489 ** Refer to the [SQL parameter] documentation for additional information. | |
| 3490 ** | |
| 3491 ** The sqlite3_result_blob() interface sets the result from | |
| 3492 ** an application-defined function to be the BLOB whose content is pointed | |
| 3493 ** to by the second parameter and which is N bytes long where N is the | |
| 3494 ** third parameter. | |
| 3495 ** | |
| 3496 ** The sqlite3_result_zeroblob() interfaces set the result of | |
| 3497 ** the application-defined function to be a BLOB containing all zero | |
| 3498 ** bytes and N bytes in size, where N is the value of the 2nd parameter. | |
| 3499 ** | |
| 3500 ** The sqlite3_result_double() interface sets the result from | |
| 3501 ** an application-defined function to be a floating point value specified | |
| 3502 ** by its 2nd argument. | |
| 3503 ** | |
| 3504 ** The sqlite3_result_error() and sqlite3_result_error16() functions | |
| 3505 ** cause the implemented SQL function to throw an exception. | |
| 3506 ** SQLite uses the string pointed to by the | |
| 3507 ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() | |
| 3508 ** as the text of an error message. SQLite interprets the error | |
| 3509 ** message string from sqlite3_result_error() as UTF-8. SQLite | |
| 3510 ** interprets the string from sqlite3_result_error16() as UTF-16 in native | |
| 3511 ** byte order. If the third parameter to sqlite3_result_error() | |
| 3512 ** or sqlite3_result_error16() is negative then SQLite takes as the error | |
| 3513 ** message all text up through the first zero character. | |
| 3514 ** If the third parameter to sqlite3_result_error() or | |
| 3515 ** sqlite3_result_error16() is non-negative then SQLite takes that many | |
| 3516 ** bytes (not characters) from the 2nd parameter as the error message. | |
| 3517 ** The sqlite3_result_error() and sqlite3_result_error16() | |
| 3518 ** routines make a private copy of the error message text before | |
| 3519 ** they return. Hence, the calling function can deallocate or | |
| 3520 ** modify the text after they return without harm. | |
| 3521 ** The sqlite3_result_error_code() function changes the error code | |
| 3522 ** returned by SQLite as a result of an error in a function. By default, | |
| 3523 ** the error code is SQLITE_ERROR. A subsequent call to sqlite3_result_error() | |
| 3524 ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR. | |
| 3525 ** | |
| 3526 ** The sqlite3_result_toobig() interface causes SQLite to throw an error | |
| 3527 ** indicating that a string or BLOB is to long to represent. | |
| 3528 ** | |
| 3529 ** The sqlite3_result_nomem() interface causes SQLite to throw an error | |
| 3530 ** indicating that a memory allocation failed. | |
| 3531 ** | |
| 3532 ** The sqlite3_result_int() interface sets the return value | |
| 3533 ** of the application-defined function to be the 32-bit signed integer | |
| 3534 ** value given in the 2nd argument. | |
| 3535 ** The sqlite3_result_int64() interface sets the return value | |
| 3536 ** of the application-defined function to be the 64-bit signed integer | |
| 3537 ** value given in the 2nd argument. | |
| 3538 ** | |
| 3539 ** The sqlite3_result_null() interface sets the return value | |
| 3540 ** of the application-defined function to be NULL. | |
| 3541 ** | |
| 3542 ** The sqlite3_result_text(), sqlite3_result_text16(), | |
| 3543 ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces | |
| 3544 ** set the return value of the application-defined function to be | |
| 3545 ** a text string which is represented as UTF-8, UTF-16 native byte order, | |
| 3546 ** UTF-16 little endian, or UTF-16 big endian, respectively. | |
| 3547 ** SQLite takes the text result from the application from | |
| 3548 ** the 2nd parameter of the sqlite3_result_text* interfaces. | |
| 3549 ** If the 3rd parameter to the sqlite3_result_text* interfaces | |
| 3550 ** is negative, then SQLite takes result text from the 2nd parameter | |
| 3551 ** through the first zero character. | |
| 3552 ** If the 3rd parameter to the sqlite3_result_text* interfaces | |
| 3553 ** is non-negative, then as many bytes (not characters) of the text | |
| 3554 ** pointed to by the 2nd parameter are taken as the application-defined | |
| 3555 ** function result. | |
| 3556 ** If the 4th parameter to the sqlite3_result_text* interfaces | |
| 3557 ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that | |
| 3558 ** function as the destructor on the text or BLOB result when it has | |
| 3559 ** finished using that result. | |
| 3560 ** If the 4th parameter to the sqlite3_result_text* interfaces or to | |
| 3561 ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite | |
| 3562 ** assumes that the text or BLOB result is in constant space and does not | |
| 3563 ** copy the content of the parameter nor call a destructor on the content | |
| 3564 ** when it has finished using that result. | |
| 3565 ** If the 4th parameter to the sqlite3_result_text* interfaces | |
| 3566 ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT | |
| 3567 ** then SQLite makes a copy of the result into space obtained from | |
| 3568 ** from [sqlite3_malloc()] before it returns. | |
| 3569 ** | |
| 3570 ** The sqlite3_result_value() interface sets the result of | |
| 3571 ** the application-defined function to be a copy the | |
| 3572 ** [unprotected sqlite3_value] object specified by the 2nd parameter. The | |
| 3573 ** sqlite3_result_value() interface makes a copy of the [sqlite3_value] | |
| 3574 ** so that the [sqlite3_value] specified in the parameter may change or | |
| 3575 ** be deallocated after sqlite3_result_value() returns without harm. | |
| 3576 ** A [protected sqlite3_value] object may always be used where an | |
| 3577 ** [unprotected sqlite3_value] object is required, so either | |
| 3578 ** kind of [sqlite3_value] object can be used with this interface. | |
| 3579 ** | |
| 3580 ** If these routines are called from within the different thread | |
| 3581 ** than the one containing the application-defined function that received | |
| 3582 ** the [sqlite3_context] pointer, the results are undefined. | |
| 3583 ** | |
| 3584 ** Requirements: | |
| 3585 ** [H16403] [H16406] [H16409] [H16412] [H16415] [H16418] [H16421] [H16424] | |
| 3586 ** [H16427] [H16430] [H16433] [H16436] [H16439] [H16442] [H16445] [H16448] | |
| 3587 ** [H16451] [H16454] [H16457] [H16460] [H16463] | |
| 3588 */ | |
| 3589 SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(
void*)); | |
| 3590 SQLITE_API void sqlite3_result_double(sqlite3_context*, double); | |
| 3591 SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int); | |
| 3592 SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int); | |
| 3593 SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*); | |
| 3594 SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*); | |
| 3595 SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int); | |
| 3596 SQLITE_API void sqlite3_result_int(sqlite3_context*, int); | |
| 3597 SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64); | |
| 3598 SQLITE_API void sqlite3_result_null(sqlite3_context*); | |
| 3599 SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(
void*)); | |
| 3600 SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*
)(void*)); | |
| 3601 SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(
*)(void*)); | |
| 3602 SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(
*)(void*)); | |
| 3603 SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*); | |
| 3604 SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n); | |
| 3605 | |
| 3606 /* | |
| 3607 ** CAPI3REF: Define New Collating Sequences {H16600} <S20300> | |
| 3608 ** | |
| 3609 ** These functions are used to add new collation sequences to the | |
| 3610 ** [database connection] specified as the first argument. | |
| 3611 ** | |
| 3612 ** The name of the new collation sequence is specified as a UTF-8 string | |
| 3613 ** for sqlite3_create_collation() and sqlite3_create_collation_v2() | |
| 3614 ** and a UTF-16 string for sqlite3_create_collation16(). In all cases | |
| 3615 ** the name is passed as the second function argument. | |
| 3616 ** | |
| 3617 ** The third argument may be one of the constants [SQLITE_UTF8], | |
| 3618 ** [SQLITE_UTF16LE], or [SQLITE_UTF16BE], indicating that the user-supplied | |
| 3619 ** routine expects to be passed pointers to strings encoded using UTF-8, | |
| 3620 ** UTF-16 little-endian, or UTF-16 big-endian, respectively. The | |
| 3621 ** third argument might also be [SQLITE_UTF16] to indicate that the routine | |
| 3622 ** expects pointers to be UTF-16 strings in the native byte order, or the | |
| 3623 ** argument can be [SQLITE_UTF16_ALIGNED] if the | |
| 3624 ** the routine expects pointers to 16-bit word aligned strings | |
| 3625 ** of UTF-16 in the native byte order. | |
| 3626 ** | |
| 3627 ** A pointer to the user supplied routine must be passed as the fifth | |
| 3628 ** argument. If it is NULL, this is the same as deleting the collation | |
| 3629 ** sequence (so that SQLite cannot call it anymore). | |
| 3630 ** Each time the application supplied function is invoked, it is passed | |
| 3631 ** as its first parameter a copy of the void* passed as the fourth argument | |
| 3632 ** to sqlite3_create_collation() or sqlite3_create_collation16(). | |
| 3633 ** | |
| 3634 ** The remaining arguments to the application-supplied routine are two strings, | |
| 3635 ** each represented by a (length, data) pair and encoded in the encoding | |
| 3636 ** that was passed as the third argument when the collation sequence was | |
| 3637 ** registered. {END} The application defined collation routine should | |
| 3638 ** return negative, zero or positive if the first string is less than, | |
| 3639 ** equal to, or greater than the second string. i.e. (STRING1 - STRING2). | |
| 3640 ** | |
| 3641 ** The sqlite3_create_collation_v2() works like sqlite3_create_collation() | |
| 3642 ** except that it takes an extra argument which is a destructor for | |
| 3643 ** the collation. The destructor is called when the collation is | |
| 3644 ** destroyed and is passed a copy of the fourth parameter void* pointer | |
| 3645 ** of the sqlite3_create_collation_v2(). | |
| 3646 ** Collations are destroyed when they are overridden by later calls to the | |
| 3647 ** collation creation functions or when the [database connection] is closed | |
| 3648 ** using [sqlite3_close()]. | |
| 3649 ** | |
| 3650 ** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()]. | |
| 3651 ** | |
| 3652 ** Requirements: | |
| 3653 ** [H16603] [H16604] [H16606] [H16609] [H16612] [H16615] [H16618] [H16621] | |
| 3654 ** [H16624] [H16627] [H16630] | |
| 3655 */ | |
| 3656 SQLITE_API int sqlite3_create_collation( | |
| 3657 sqlite3*, | |
| 3658 const char *zName, | |
| 3659 int eTextRep, | |
| 3660 void*, | |
| 3661 int(*xCompare)(void*,int,const void*,int,const void*) | |
| 3662 ); | |
| 3663 SQLITE_API int sqlite3_create_collation_v2( | |
| 3664 sqlite3*, | |
| 3665 const char *zName, | |
| 3666 int eTextRep, | |
| 3667 void*, | |
| 3668 int(*xCompare)(void*,int,const void*,int,const void*), | |
| 3669 void(*xDestroy)(void*) | |
| 3670 ); | |
| 3671 SQLITE_API int sqlite3_create_collation16( | |
| 3672 sqlite3*, | |
| 3673 const void *zName, | |
| 3674 int eTextRep, | |
| 3675 void*, | |
| 3676 int(*xCompare)(void*,int,const void*,int,const void*) | |
| 3677 ); | |
| 3678 | |
| 3679 /* | |
| 3680 ** CAPI3REF: Collation Needed Callbacks {H16700} <S20300> | |
| 3681 ** | |
| 3682 ** To avoid having to register all collation sequences before a database | |
| 3683 ** can be used, a single callback function may be registered with the | |
| 3684 ** [database connection] to be called whenever an undefined collation | |
| 3685 ** sequence is required. | |
| 3686 ** | |
| 3687 ** If the function is registered using the sqlite3_collation_needed() API, | |
| 3688 ** then it is passed the names of undefined collation sequences as strings | |
| 3689 ** encoded in UTF-8. {H16703} If sqlite3_collation_needed16() is used, | |
| 3690 ** the names are passed as UTF-16 in machine native byte order. | |
| 3691 ** A call to either function replaces any existing callback. | |
| 3692 ** | |
| 3693 ** When the callback is invoked, the first argument passed is a copy | |
| 3694 ** of the second argument to sqlite3_collation_needed() or | |
| 3695 ** sqlite3_collation_needed16(). The second argument is the database | |
| 3696 ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], | |
| 3697 ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation | |
| 3698 ** sequence function required. The fourth parameter is the name of the | |
| 3699 ** required collation sequence. | |
| 3700 ** | |
| 3701 ** The callback function should register the desired collation using | |
| 3702 ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or | |
| 3703 ** [sqlite3_create_collation_v2()]. | |
| 3704 ** | |
| 3705 ** Requirements: | |
| 3706 ** [H16702] [H16704] [H16706] | |
| 3707 */ | |
| 3708 SQLITE_API int sqlite3_collation_needed( | |
| 3709 sqlite3*, | |
| 3710 void*, | |
| 3711 void(*)(void*,sqlite3*,int eTextRep,const char*) | |
| 3712 ); | |
| 3713 SQLITE_API int sqlite3_collation_needed16( | |
| 3714 sqlite3*, | |
| 3715 void*, | |
| 3716 void(*)(void*,sqlite3*,int eTextRep,const void*) | |
| 3717 ); | |
| 3718 | |
| 3719 /* | |
| 3720 ** Specify the key for an encrypted database. This routine should be | |
| 3721 ** called right after sqlite3_open(). | |
| 3722 ** | |
| 3723 ** The code to implement this API is not available in the public release | |
| 3724 ** of SQLite. | |
| 3725 */ | |
| 3726 SQLITE_API int sqlite3_key( | |
| 3727 sqlite3 *db, /* Database to be rekeyed */ | |
| 3728 const void *pKey, int nKey /* The key */ | |
| 3729 ); | |
| 3730 | |
| 3731 /* | |
| 3732 ** Change the key on an open database. If the current database is not | |
| 3733 ** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the | |
| 3734 ** database is decrypted. | |
| 3735 ** | |
| 3736 ** The code to implement this API is not available in the public release | |
| 3737 ** of SQLite. | |
| 3738 */ | |
| 3739 SQLITE_API int sqlite3_rekey( | |
| 3740 sqlite3 *db, /* Database to be rekeyed */ | |
| 3741 const void *pKey, int nKey /* The new key */ | |
| 3742 ); | |
| 3743 | |
| 3744 /* | |
| 3745 ** CAPI3REF: Suspend Execution For A Short Time {H10530} <S40410> | |
| 3746 ** | |
| 3747 ** The sqlite3_sleep() function causes the current thread to suspend execution | |
| 3748 ** for at least a number of milliseconds specified in its parameter. | |
| 3749 ** | |
| 3750 ** If the operating system does not support sleep requests with | |
| 3751 ** millisecond time resolution, then the time will be rounded up to | |
| 3752 ** the nearest second. The number of milliseconds of sleep actually | |
| 3753 ** requested from the operating system is returned. | |
| 3754 ** | |
| 3755 ** SQLite implements this interface by calling the xSleep() | |
| 3756 ** method of the default [sqlite3_vfs] object. | |
| 3757 ** | |
| 3758 ** Requirements: [H10533] [H10536] | |
| 3759 */ | |
| 3760 SQLITE_API int sqlite3_sleep(int); | |
| 3761 | |
| 3762 /* | |
| 3763 ** CAPI3REF: Name Of The Folder Holding Temporary Files {H10310} <S20000> | |
| 3764 ** | |
| 3765 ** If this global variable is made to point to a string which is | |
| 3766 ** the name of a folder (a.k.a. directory), then all temporary files | |
| 3767 ** created by SQLite will be placed in that directory. If this variable | |
| 3768 ** is a NULL pointer, then SQLite performs a search for an appropriate | |
| 3769 ** temporary file directory. | |
| 3770 ** | |
| 3771 ** It is not safe to read or modify this variable in more than one | |
| 3772 ** thread at a time. It is not safe to read or modify this variable | |
| 3773 ** if a [database connection] is being used at the same time in a separate | |
| 3774 ** thread. | |
| 3775 ** It is intended that this variable be set once | |
| 3776 ** as part of process initialization and before any SQLite interface | |
| 3777 ** routines have been called and that this variable remain unchanged | |
| 3778 ** thereafter. | |
| 3779 ** | |
| 3780 ** The [temp_store_directory pragma] may modify this variable and cause | |
| 3781 ** it to point to memory obtained from [sqlite3_malloc]. Furthermore, | |
| 3782 ** the [temp_store_directory pragma] always assumes that any string | |
| 3783 ** that this variable points to is held in memory obtained from | |
| 3784 ** [sqlite3_malloc] and the pragma may attempt to free that memory | |
| 3785 ** using [sqlite3_free]. | |
| 3786 ** Hence, if this variable is modified directly, either it should be | |
| 3787 ** made NULL or made to point to memory obtained from [sqlite3_malloc] | |
| 3788 ** or else the use of the [temp_store_directory pragma] should be avoided. | |
| 3789 */ | |
| 3790 SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory; | |
| 3791 | |
| 3792 /* | |
| 3793 ** CAPI3REF: Test For Auto-Commit Mode {H12930} <S60200> | |
| 3794 ** KEYWORDS: {autocommit mode} | |
| 3795 ** | |
| 3796 ** The sqlite3_get_autocommit() interface returns non-zero or | |
| 3797 ** zero if the given database connection is or is not in autocommit mode, | |
| 3798 ** respectively. Autocommit mode is on by default. | |
| 3799 ** Autocommit mode is disabled by a [BEGIN] statement. | |
| 3800 ** Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK]. | |
| 3801 ** | |
| 3802 ** If certain kinds of errors occur on a statement within a multi-statement | |
| 3803 ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR], | |
| 3804 ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the | |
| 3805 ** transaction might be rolled back automatically. The only way to | |
| 3806 ** find out whether SQLite automatically rolled back the transaction after | |
| 3807 ** an error is to use this function. | |
| 3808 ** | |
| 3809 ** If another thread changes the autocommit status of the database | |
| 3810 ** connection while this routine is running, then the return value | |
| 3811 ** is undefined. | |
| 3812 ** | |
| 3813 ** Requirements: [H12931] [H12932] [H12933] [H12934] | |
| 3814 */ | |
| 3815 SQLITE_API int sqlite3_get_autocommit(sqlite3*); | |
| 3816 | |
| 3817 /* | |
| 3818 ** CAPI3REF: Find The Database Handle Of A Prepared Statement {H13120} <S60600> | |
| 3819 ** | |
| 3820 ** The sqlite3_db_handle interface returns the [database connection] handle | |
| 3821 ** to which a [prepared statement] belongs. The [database connection] | |
| 3822 ** returned by sqlite3_db_handle is the same [database connection] that was the
first argument | |
| 3823 ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to | |
| 3824 ** create the statement in the first place. | |
| 3825 ** | |
| 3826 ** Requirements: [H13123] | |
| 3827 */ | |
| 3828 SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*); | |
| 3829 | |
| 3830 /* | |
| 3831 ** CAPI3REF: Find the next prepared statement {H13140} <S60600> | |
| 3832 ** | |
| 3833 ** This interface returns a pointer to the next [prepared statement] after | |
| 3834 ** pStmt associated with the [database connection] pDb. If pStmt is NULL | |
| 3835 ** then this interface returns a pointer to the first prepared statement | |
| 3836 ** associated with the database connection pDb. If no prepared statement | |
| 3837 ** satisfies the conditions of this routine, it returns NULL. | |
| 3838 ** | |
| 3839 ** The [database connection] pointer D in a call to | |
| 3840 ** [sqlite3_next_stmt(D,S)] must refer to an open database | |
| 3841 ** connection and in particular must not be a NULL pointer. | |
| 3842 ** | |
| 3843 ** Requirements: [H13143] [H13146] [H13149] [H13152] | |
| 3844 */ | |
| 3845 SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt); | |
| 3846 | |
| 3847 /* | |
| 3848 ** CAPI3REF: Commit And Rollback Notification Callbacks {H12950} <S60400> | |
| 3849 ** | |
| 3850 ** The sqlite3_commit_hook() interface registers a callback | |
| 3851 ** function to be invoked whenever a transaction is [COMMIT | committed]. | |
| 3852 ** Any callback set by a previous call to sqlite3_commit_hook() | |
| 3853 ** for the same database connection is overridden. | |
| 3854 ** The sqlite3_rollback_hook() interface registers a callback | |
| 3855 ** function to be invoked whenever a transaction is [ROLLBACK | rolled back]. | |
| 3856 ** Any callback set by a previous call to sqlite3_commit_hook() | |
| 3857 ** for the same database connection is overridden. | |
| 3858 ** The pArg argument is passed through to the callback. | |
| 3859 ** If the callback on a commit hook function returns non-zero, | |
| 3860 ** then the commit is converted into a rollback. | |
| 3861 ** | |
| 3862 ** If another function was previously registered, its | |
| 3863 ** pArg value is returned. Otherwise NULL is returned. | |
| 3864 ** | |
| 3865 ** The callback implementation must not do anything that will modify | |
| 3866 ** the database connection that invoked the callback. Any actions | |
| 3867 ** to modify the database connection must be deferred until after the | |
| 3868 ** completion of the [sqlite3_step()] call that triggered the commit | |
| 3869 ** or rollback hook in the first place. | |
| 3870 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their | |
| 3871 ** database connections for the meaning of "modify" in this paragraph. | |
| 3872 ** | |
| 3873 ** Registering a NULL function disables the callback. | |
| 3874 ** | |
| 3875 ** When the commit hook callback routine returns zero, the [COMMIT] | |
| 3876 ** operation is allowed to continue normally. If the commit hook | |
| 3877 ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK]. | |
| 3878 ** The rollback hook is invoked on a rollback that results from a commit | |
| 3879 ** hook returning non-zero, just as it would be with any other rollback. | |
| 3880 ** | |
| 3881 ** For the purposes of this API, a transaction is said to have been | |
| 3882 ** rolled back if an explicit "ROLLBACK" statement is executed, or | |
| 3883 ** an error or constraint causes an implicit rollback to occur. | |
| 3884 ** The rollback callback is not invoked if a transaction is | |
| 3885 ** automatically rolled back because the database connection is closed. | |
| 3886 ** The rollback callback is not invoked if a transaction is | |
| 3887 ** rolled back because a commit callback returned non-zero. | |
| 3888 ** <todo> Check on this </todo> | |
| 3889 ** | |
| 3890 ** See also the [sqlite3_update_hook()] interface. | |
| 3891 ** | |
| 3892 ** Requirements: | |
| 3893 ** [H12951] [H12952] [H12953] [H12954] [H12955] | |
| 3894 ** [H12961] [H12962] [H12963] [H12964] | |
| 3895 */ | |
| 3896 SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); | |
| 3897 SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); | |
| 3898 | |
| 3899 /* | |
| 3900 ** CAPI3REF: Data Change Notification Callbacks {H12970} <S60400> | |
| 3901 ** | |
| 3902 ** The sqlite3_update_hook() interface registers a callback function | |
| 3903 ** with the [database connection] identified by the first argument | |
| 3904 ** to be invoked whenever a row is updated, inserted or deleted. | |
| 3905 ** Any callback set by a previous call to this function | |
| 3906 ** for the same database connection is overridden. | |
| 3907 ** | |
| 3908 ** The second argument is a pointer to the function to invoke when a | |
| 3909 ** row is updated, inserted or deleted. | |
| 3910 ** The first argument to the callback is a copy of the third argument | |
| 3911 ** to sqlite3_update_hook(). | |
| 3912 ** The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE], | |
| 3913 ** or [SQLITE_UPDATE], depending on the operation that caused the callback | |
| 3914 ** to be invoked. | |
| 3915 ** The third and fourth arguments to the callback contain pointers to the | |
| 3916 ** database and table name containing the affected row. | |
| 3917 ** The final callback parameter is the [rowid] of the row. | |
| 3918 ** In the case of an update, this is the [rowid] after the update takes place. | |
| 3919 ** | |
| 3920 ** The update hook is not invoked when internal system tables are | |
| 3921 ** modified (i.e. sqlite_master and sqlite_sequence). | |
| 3922 ** | |
| 3923 ** In the current implementation, the update hook | |
| 3924 ** is not invoked when duplication rows are deleted because of an | |
| 3925 ** [ON CONFLICT | ON CONFLICT REPLACE] clause. Nor is the update hook | |
| 3926 ** invoked when rows are deleted using the [truncate optimization]. | |
| 3927 ** The exceptions defined in this paragraph might change in a future | |
| 3928 ** release of SQLite. | |
| 3929 ** | |
| 3930 ** The update hook implementation must not do anything that will modify | |
| 3931 ** the database connection that invoked the update hook. Any actions | |
| 3932 ** to modify the database connection must be deferred until after the | |
| 3933 ** completion of the [sqlite3_step()] call that triggered the update hook. | |
| 3934 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their | |
| 3935 ** database connections for the meaning of "modify" in this paragraph. | |
| 3936 ** | |
| 3937 ** If another function was previously registered, its pArg value | |
| 3938 ** is returned. Otherwise NULL is returned. | |
| 3939 ** | |
| 3940 ** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()] | |
| 3941 ** interfaces. | |
| 3942 ** | |
| 3943 ** Requirements: | |
| 3944 ** [H12971] [H12973] [H12975] [H12977] [H12979] [H12981] [H12983] [H12986] | |
| 3945 */ | |
| 3946 SQLITE_API void *sqlite3_update_hook( | |
| 3947 sqlite3*, | |
| 3948 void(*)(void *,int ,char const *,char const *,sqlite3_int64), | |
| 3949 void* | |
| 3950 ); | |
| 3951 | |
| 3952 /* | |
| 3953 ** CAPI3REF: Enable Or Disable Shared Pager Cache {H10330} <S30900> | |
| 3954 ** KEYWORDS: {shared cache} | |
| 3955 ** | |
| 3956 ** This routine enables or disables the sharing of the database cache | |
| 3957 ** and schema data structures between [database connection | connections] | |
| 3958 ** to the same database. Sharing is enabled if the argument is true | |
| 3959 ** and disabled if the argument is false. | |
| 3960 ** | |
| 3961 ** Cache sharing is enabled and disabled for an entire process. | |
| 3962 ** This is a change as of SQLite version 3.5.0. In prior versions of SQLite, | |
| 3963 ** sharing was enabled or disabled for each thread separately. | |
| 3964 ** | |
| 3965 ** The cache sharing mode set by this interface effects all subsequent | |
| 3966 ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. | |
| 3967 ** Existing database connections continue use the sharing mode | |
| 3968 ** that was in effect at the time they were opened. | |
| 3969 ** | |
| 3970 ** Virtual tables cannot be used with a shared cache. When shared | |
| 3971 ** cache is enabled, the [sqlite3_create_module()] API used to register | |
| 3972 ** virtual tables will always return an error. | |
| 3973 ** | |
| 3974 ** This routine returns [SQLITE_OK] if shared cache was enabled or disabled | |
| 3975 ** successfully. An [error code] is returned otherwise. | |
| 3976 ** | |
| 3977 ** Shared cache is disabled by default. But this might change in | |
| 3978 ** future releases of SQLite. Applications that care about shared | |
| 3979 ** cache setting should set it explicitly. | |
| 3980 ** | |
| 3981 ** See Also: [SQLite Shared-Cache Mode] | |
| 3982 ** | |
| 3983 ** Requirements: [H10331] [H10336] [H10337] [H10339] | |
| 3984 */ | |
| 3985 SQLITE_API int sqlite3_enable_shared_cache(int); | |
| 3986 | |
| 3987 /* | |
| 3988 ** CAPI3REF: Attempt To Free Heap Memory {H17340} <S30220> | |
| 3989 ** | |
| 3990 ** The sqlite3_release_memory() interface attempts to free N bytes | |
| 3991 ** of heap memory by deallocating non-essential memory allocations | |
| 3992 ** held by the database library. {END} Memory used to cache database | |
| 3993 ** pages to improve performance is an example of non-essential memory. | |
| 3994 ** sqlite3_release_memory() returns the number of bytes actually freed, | |
| 3995 ** which might be more or less than the amount requested. | |
| 3996 ** | |
| 3997 ** Requirements: [H17341] [H17342] | |
| 3998 */ | |
| 3999 SQLITE_API int sqlite3_release_memory(int); | |
| 4000 | |
| 4001 /* | |
| 4002 ** CAPI3REF: Impose A Limit On Heap Size {H17350} <S30220> | |
| 4003 ** | |
| 4004 ** The sqlite3_soft_heap_limit() interface places a "soft" limit | |
| 4005 ** on the amount of heap memory that may be allocated by SQLite. | |
| 4006 ** If an internal allocation is requested that would exceed the | |
| 4007 ** soft heap limit, [sqlite3_release_memory()] is invoked one or | |
| 4008 ** more times to free up some space before the allocation is performed. | |
| 4009 ** | |
| 4010 ** The limit is called "soft", because if [sqlite3_release_memory()] | |
| 4011 ** cannot free sufficient memory to prevent the limit from being exceeded, | |
| 4012 ** the memory is allocated anyway and the current operation proceeds. | |
| 4013 ** | |
| 4014 ** A negative or zero value for N means that there is no soft heap limit and | |
| 4015 ** [sqlite3_release_memory()] will only be called when memory is exhausted. | |
| 4016 ** The default value for the soft heap limit is zero. | |
| 4017 ** | |
| 4018 ** SQLite makes a best effort to honor the soft heap limit. | |
| 4019 ** But if the soft heap limit cannot be honored, execution will | |
| 4020 ** continue without error or notification. This is why the limit is | |
| 4021 ** called a "soft" limit. It is advisory only. | |
| 4022 ** | |
| 4023 ** Prior to SQLite version 3.5.0, this routine only constrained the memory | |
| 4024 ** allocated by a single thread - the same thread in which this routine | |
| 4025 ** runs. Beginning with SQLite version 3.5.0, the soft heap limit is | |
| 4026 ** applied to all threads. The value specified for the soft heap limit | |
| 4027 ** is an upper bound on the total memory allocation for all threads. In | |
| 4028 ** version 3.5.0 there is no mechanism for limiting the heap usage for | |
| 4029 ** individual threads. | |
| 4030 ** | |
| 4031 ** Requirements: | |
| 4032 ** [H16351] [H16352] [H16353] [H16354] [H16355] [H16358] | |
| 4033 */ | |
| 4034 SQLITE_API void sqlite3_soft_heap_limit(int); | |
| 4035 | |
| 4036 /* | |
| 4037 ** CAPI3REF: Extract Metadata About A Column Of A Table {H12850} <S60300> | |
| 4038 ** | |
| 4039 ** This routine returns metadata about a specific column of a specific | |
| 4040 ** database table accessible using the [database connection] handle | |
| 4041 ** passed as the first function argument. | |
| 4042 ** | |
| 4043 ** The column is identified by the second, third and fourth parameters to | |
| 4044 ** this function. The second parameter is either the name of the database | |
| 4045 ** (i.e. "main", "temp" or an attached database) containing the specified | |
| 4046 ** table or NULL. If it is NULL, then all attached databases are searched | |
| 4047 ** for the table using the same algorithm used by the database engine to | |
| 4048 ** resolve unqualified table references. | |
| 4049 ** | |
| 4050 ** The third and fourth parameters to this function are the table and column | |
| 4051 ** name of the desired column, respectively. Neither of these parameters | |
| 4052 ** may be NULL. | |
| 4053 ** | |
| 4054 ** Metadata is returned by writing to the memory locations passed as the 5th | |
| 4055 ** and subsequent parameters to this function. Any of these arguments may be | |
| 4056 ** NULL, in which case the corresponding element of metadata is omitted. | |
| 4057 ** | |
| 4058 ** <blockquote> | |
| 4059 ** <table border="1"> | |
| 4060 ** <tr><th> Parameter <th> Output<br>Type <th> Description | |
| 4061 ** | |
| 4062 ** <tr><td> 5th <td> const char* <td> Data type | |
| 4063 ** <tr><td> 6th <td> const char* <td> Name of default collation sequence | |
| 4064 ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint | |
| 4065 ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY | |
| 4066 ** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT] | |
| 4067 ** </table> | |
| 4068 ** </blockquote> | |
| 4069 ** | |
| 4070 ** The memory pointed to by the character pointers returned for the | |
| 4071 ** declaration type and collation sequence is valid only until the next | |
| 4072 ** call to any SQLite API function. | |
| 4073 ** | |
| 4074 ** If the specified table is actually a view, an [error code] is returned. | |
| 4075 ** | |
| 4076 ** If the specified column is "rowid", "oid" or "_rowid_" and an | |
| 4077 ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output | |
| 4078 ** parameters are set for the explicitly declared column. If there is no | |
| 4079 ** explicitly declared [INTEGER PRIMARY KEY] column, then the output | |
| 4080 ** parameters are set as follows: | |
| 4081 ** | |
| 4082 ** <pre> | |
| 4083 ** data type: "INTEGER" | |
| 4084 ** collation sequence: "BINARY" | |
| 4085 ** not null: 0 | |
| 4086 ** primary key: 1 | |
| 4087 ** auto increment: 0 | |
| 4088 ** </pre> | |
| 4089 ** | |
| 4090 ** This function may load one or more schemas from database files. If an | |
| 4091 ** error occurs during this process, or if the requested table or column | |
| 4092 ** cannot be found, an [error code] is returned and an error message left | |
| 4093 ** in the [database connection] (to be retrieved using sqlite3_errmsg()). | |
| 4094 ** | |
| 4095 ** This API is only available if the library was compiled with the | |
| 4096 ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined. | |
| 4097 */ | |
| 4098 SQLITE_API int sqlite3_table_column_metadata( | |
| 4099 sqlite3 *db, /* Connection handle */ | |
| 4100 const char *zDbName, /* Database name or NULL */ | |
| 4101 const char *zTableName, /* Table name */ | |
| 4102 const char *zColumnName, /* Column name */ | |
| 4103 char const **pzDataType, /* OUTPUT: Declared data type */ | |
| 4104 char const **pzCollSeq, /* OUTPUT: Collation sequence name */ | |
| 4105 int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ | |
| 4106 int *pPrimaryKey, /* OUTPUT: True if column part of PK */ | |
| 4107 int *pAutoinc /* OUTPUT: True if column is auto-increment */ | |
| 4108 ); | |
| 4109 | |
| 4110 /* | |
| 4111 ** CAPI3REF: Load An Extension {H12600} <S20500> | |
| 4112 ** | |
| 4113 ** This interface loads an SQLite extension library from the named file. | |
| 4114 ** | |
| 4115 ** {H12601} The sqlite3_load_extension() interface attempts to load an | |
| 4116 ** SQLite extension library contained in the file zFile. | |
| 4117 ** | |
| 4118 ** {H12602} The entry point is zProc. | |
| 4119 ** | |
| 4120 ** {H12603} zProc may be 0, in which case the name of the entry point | |
| 4121 ** defaults to "sqlite3_extension_init". | |
| 4122 ** | |
| 4123 ** {H12604} The sqlite3_load_extension() interface shall return | |
| 4124 ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. | |
| 4125 ** | |
| 4126 ** {H12605} If an error occurs and pzErrMsg is not 0, then the | |
| 4127 ** [sqlite3_load_extension()] interface shall attempt to | |
| 4128 ** fill *pzErrMsg with error message text stored in memory | |
| 4129 ** obtained from [sqlite3_malloc()]. {END} The calling function | |
| 4130 ** should free this memory by calling [sqlite3_free()]. | |
| 4131 ** | |
| 4132 ** {H12606} Extension loading must be enabled using | |
| 4133 ** [sqlite3_enable_load_extension()] prior to calling this API, | |
| 4134 ** otherwise an error will be returned. | |
| 4135 */ | |
| 4136 SQLITE_API int sqlite3_load_extension( | |
| 4137 sqlite3 *db, /* Load the extension into this database connection */ | |
| 4138 const char *zFile, /* Name of the shared library containing extension */ | |
| 4139 const char *zProc, /* Entry point. Derived from zFile if 0 */ | |
| 4140 char **pzErrMsg /* Put error message here if not 0 */ | |
| 4141 ); | |
| 4142 | |
| 4143 /* | |
| 4144 ** CAPI3REF: Enable Or Disable Extension Loading {H12620} <S20500> | |
| 4145 ** | |
| 4146 ** So as not to open security holes in older applications that are | |
| 4147 ** unprepared to deal with extension loading, and as a means of disabling | |
| 4148 ** extension loading while evaluating user-entered SQL, the following API | |
| 4149 ** is provided to turn the [sqlite3_load_extension()] mechanism on and off. | |
| 4150 ** | |
| 4151 ** Extension loading is off by default. See ticket #1863. | |
| 4152 ** | |
| 4153 ** {H12621} Call the sqlite3_enable_load_extension() routine with onoff==1 | |
| 4154 ** to turn extension loading on and call it with onoff==0 to turn | |
| 4155 ** it back off again. | |
| 4156 ** | |
| 4157 ** {H12622} Extension loading is off by default. | |
| 4158 */ | |
| 4159 SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff); | |
| 4160 | |
| 4161 /* | |
| 4162 ** CAPI3REF: Automatically Load An Extensions {H12640} <S20500> | |
| 4163 ** | |
| 4164 ** This API can be invoked at program startup in order to register | |
| 4165 ** one or more statically linked extensions that will be available | |
| 4166 ** to all new [database connections]. {END} | |
| 4167 ** | |
| 4168 ** This routine stores a pointer to the extension in an array that is | |
| 4169 ** obtained from [sqlite3_malloc()]. If you run a memory leak checker | |
| 4170 ** on your program and it reports a leak because of this array, invoke | |
| 4171 ** [sqlite3_reset_auto_extension()] prior to shutdown to free the memory. | |
| 4172 ** | |
| 4173 ** {H12641} This function registers an extension entry point that is | |
| 4174 ** automatically invoked whenever a new [database connection] | |
| 4175 ** is opened using [sqlite3_open()], [sqlite3_open16()], | |
| 4176 ** or [sqlite3_open_v2()]. | |
| 4177 ** | |
| 4178 ** {H12642} Duplicate extensions are detected so calling this routine | |
| 4179 ** multiple times with the same extension is harmless. | |
| 4180 ** | |
| 4181 ** {H12643} This routine stores a pointer to the extension in an array | |
| 4182 ** that is obtained from [sqlite3_malloc()]. | |
| 4183 ** | |
| 4184 ** {H12644} Automatic extensions apply across all threads. | |
| 4185 */ | |
| 4186 SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void)); | |
| 4187 | |
| 4188 /* | |
| 4189 ** CAPI3REF: Reset Automatic Extension Loading {H12660} <S20500> | |
| 4190 ** | |
| 4191 ** This function disables all previously registered automatic | |
| 4192 ** extensions. {END} It undoes the effect of all prior | |
| 4193 ** [sqlite3_auto_extension()] calls. | |
| 4194 ** | |
| 4195 ** {H12661} This function disables all previously registered | |
| 4196 ** automatic extensions. | |
| 4197 ** | |
| 4198 ** {H12662} This function disables automatic extensions in all threads. | |
| 4199 */ | |
| 4200 SQLITE_API void sqlite3_reset_auto_extension(void); | |
| 4201 | |
| 4202 /* | |
| 4203 ****** EXPERIMENTAL - subject to change without notice ************** | |
| 4204 ** | |
| 4205 ** The interface to the virtual-table mechanism is currently considered | |
| 4206 ** to be experimental. The interface might change in incompatible ways. | |
| 4207 ** If this is a problem for you, do not use the interface at this time. | |
| 4208 ** | |
| 4209 ** When the virtual-table mechanism stabilizes, we will declare the | |
| 4210 ** interface fixed, support it indefinitely, and remove this comment. | |
| 4211 */ | |
| 4212 | |
| 4213 /* | |
| 4214 ** Structures used by the virtual table interface | |
| 4215 */ | |
| 4216 typedef struct sqlite3_vtab sqlite3_vtab; | |
| 4217 typedef struct sqlite3_index_info sqlite3_index_info; | |
| 4218 typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; | |
| 4219 typedef struct sqlite3_module sqlite3_module; | |
| 4220 | |
| 4221 /* | |
| 4222 ** CAPI3REF: Virtual Table Object {H18000} <S20400> | |
| 4223 ** KEYWORDS: sqlite3_module {virtual table module} | |
| 4224 ** EXPERIMENTAL | |
| 4225 ** | |
| 4226 ** This structure, sometimes called a a "virtual table module", | |
| 4227 ** defines the implementation of a [virtual tables]. | |
| 4228 ** This structure consists mostly of methods for the module. | |
| 4229 ** | |
| 4230 ** A virtual table module is created by filling in a persistent | |
| 4231 ** instance of this structure and passing a pointer to that instance | |
| 4232 ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()]. | |
| 4233 ** The registration remains valid until it is replaced by a different | |
| 4234 ** module or until the [database connection] closes. The content | |
| 4235 ** of this structure must not change while it is registered with | |
| 4236 ** any database connection. | |
| 4237 */ | |
| 4238 struct sqlite3_module { | |
| 4239 int iVersion; | |
| 4240 int (*xCreate)(sqlite3*, void *pAux, | |
| 4241 int argc, const char *const*argv, | |
| 4242 sqlite3_vtab **ppVTab, char**); | |
| 4243 int (*xConnect)(sqlite3*, void *pAux, | |
| 4244 int argc, const char *const*argv, | |
| 4245 sqlite3_vtab **ppVTab, char**); | |
| 4246 int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); | |
| 4247 int (*xDisconnect)(sqlite3_vtab *pVTab); | |
| 4248 int (*xDestroy)(sqlite3_vtab *pVTab); | |
| 4249 int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); | |
| 4250 int (*xClose)(sqlite3_vtab_cursor*); | |
| 4251 int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, | |
| 4252 int argc, sqlite3_value **argv); | |
| 4253 int (*xNext)(sqlite3_vtab_cursor*); | |
| 4254 int (*xEof)(sqlite3_vtab_cursor*); | |
| 4255 int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); | |
| 4256 int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); | |
| 4257 int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); | |
| 4258 int (*xBegin)(sqlite3_vtab *pVTab); | |
| 4259 int (*xSync)(sqlite3_vtab *pVTab); | |
| 4260 int (*xCommit)(sqlite3_vtab *pVTab); | |
| 4261 int (*xRollback)(sqlite3_vtab *pVTab); | |
| 4262 int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, | |
| 4263 void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), | |
| 4264 void **ppArg); | |
| 4265 int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); | |
| 4266 }; | |
| 4267 | |
| 4268 /* | |
| 4269 ** CAPI3REF: Virtual Table Indexing Information {H18100} <S20400> | |
| 4270 ** KEYWORDS: sqlite3_index_info | |
| 4271 ** EXPERIMENTAL | |
| 4272 ** | |
| 4273 ** The sqlite3_index_info structure and its substructures is used to | |
| 4274 ** pass information into and receive the reply from the [xBestIndex] | |
| 4275 ** method of a [virtual table module]. The fields under **Inputs** are the | |
| 4276 ** inputs to xBestIndex and are read-only. xBestIndex inserts its | |
| 4277 ** results into the **Outputs** fields. | |
| 4278 ** | |
| 4279 ** The aConstraint[] array records WHERE clause constraints of the form: | |
| 4280 ** | |
| 4281 ** <pre>column OP expr</pre> | |
| 4282 ** | |
| 4283 ** where OP is =, <, <=, >, or >=. The particular operator is | |
| 4284 ** stored in aConstraint[].op. The index of the column is stored in | |
| 4285 ** aConstraint[].iColumn. aConstraint[].usable is TRUE if the | |
| 4286 ** expr on the right-hand side can be evaluated (and thus the constraint | |
| 4287 ** is usable) and false if it cannot. | |
| 4288 ** | |
| 4289 ** The optimizer automatically inverts terms of the form "expr OP column" | |
| 4290 ** and makes other simplifications to the WHERE clause in an attempt to | |
| 4291 ** get as many WHERE clause terms into the form shown above as possible. | |
| 4292 ** The aConstraint[] array only reports WHERE clause terms in the correct | |
| 4293 ** form that refer to the particular virtual table being queried. | |
| 4294 ** | |
| 4295 ** Information about the ORDER BY clause is stored in aOrderBy[]. | |
| 4296 ** Each term of aOrderBy records a column of the ORDER BY clause. | |
| 4297 ** | |
| 4298 ** The [xBestIndex] method must fill aConstraintUsage[] with information | |
| 4299 ** about what parameters to pass to xFilter. If argvIndex>0 then | |
| 4300 ** the right-hand side of the corresponding aConstraint[] is evaluated | |
| 4301 ** and becomes the argvIndex-th entry in argv. If aConstraintUsage[].omit | |
| 4302 ** is true, then the constraint is assumed to be fully handled by the | |
| 4303 ** virtual table and is not checked again by SQLite. | |
| 4304 ** | |
| 4305 ** The idxNum and idxPtr values are recorded and passed into the | |
| 4306 ** [xFilter] method. | |
| 4307 ** [sqlite3_free()] is used to free idxPtr if and only iff | |
| 4308 ** needToFreeIdxPtr is true. | |
| 4309 ** | |
| 4310 ** The orderByConsumed means that output from [xFilter]/[xNext] will occur in | |
| 4311 ** the correct order to satisfy the ORDER BY clause so that no separate | |
| 4312 ** sorting step is required. | |
| 4313 ** | |
| 4314 ** The estimatedCost value is an estimate of the cost of doing the | |
| 4315 ** particular lookup. A full scan of a table with N entries should have | |
| 4316 ** a cost of N. A binary search of a table of N entries should have a | |
| 4317 ** cost of approximately log(N). | |
| 4318 */ | |
| 4319 struct sqlite3_index_info { | |
| 4320 /* Inputs */ | |
| 4321 int nConstraint; /* Number of entries in aConstraint */ | |
| 4322 struct sqlite3_index_constraint { | |
| 4323 int iColumn; /* Column on left-hand side of constraint */ | |
| 4324 unsigned char op; /* Constraint operator */ | |
| 4325 unsigned char usable; /* True if this constraint is usable */ | |
| 4326 int iTermOffset; /* Used internally - xBestIndex should ignore */ | |
| 4327 } *aConstraint; /* Table of WHERE clause constraints */ | |
| 4328 int nOrderBy; /* Number of terms in the ORDER BY clause */ | |
| 4329 struct sqlite3_index_orderby { | |
| 4330 int iColumn; /* Column number */ | |
| 4331 unsigned char desc; /* True for DESC. False for ASC. */ | |
| 4332 } *aOrderBy; /* The ORDER BY clause */ | |
| 4333 /* Outputs */ | |
| 4334 struct sqlite3_index_constraint_usage { | |
| 4335 int argvIndex; /* if >0, constraint is part of argv to xFilter */ | |
| 4336 unsigned char omit; /* Do not code a test for this constraint */ | |
| 4337 } *aConstraintUsage; | |
| 4338 int idxNum; /* Number used to identify the index */ | |
| 4339 char *idxStr; /* String, possibly obtained from sqlite3_malloc */ | |
| 4340 int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ | |
| 4341 int orderByConsumed; /* True if output is already ordered */ | |
| 4342 double estimatedCost; /* Estimated cost of using this index */ | |
| 4343 }; | |
| 4344 #define SQLITE_INDEX_CONSTRAINT_EQ 2 | |
| 4345 #define SQLITE_INDEX_CONSTRAINT_GT 4 | |
| 4346 #define SQLITE_INDEX_CONSTRAINT_LE 8 | |
| 4347 #define SQLITE_INDEX_CONSTRAINT_LT 16 | |
| 4348 #define SQLITE_INDEX_CONSTRAINT_GE 32 | |
| 4349 #define SQLITE_INDEX_CONSTRAINT_MATCH 64 | |
| 4350 | |
| 4351 /* | |
| 4352 ** CAPI3REF: Register A Virtual Table Implementation {H18200} <S20400> | |
| 4353 ** EXPERIMENTAL | |
| 4354 ** | |
| 4355 ** This routine is used to register a new [virtual table module] name. | |
| 4356 ** Module names must be registered before | |
| 4357 ** creating a new [virtual table] using the module, or before using a | |
| 4358 ** preexisting [virtual table] for the module. | |
| 4359 ** | |
| 4360 ** The module name is registered on the [database connection] specified | |
| 4361 ** by the first parameter. The name of the module is given by the | |
| 4362 ** second parameter. The third parameter is a pointer to | |
| 4363 ** the implementation of the [virtual table module]. The fourth | |
| 4364 ** parameter is an arbitrary client data pointer that is passed through | |
| 4365 ** into the [xCreate] and [xConnect] methods of the virtual table module | |
| 4366 ** when a new virtual table is be being created or reinitialized. | |
| 4367 ** | |
| 4368 ** This interface has exactly the same effect as calling | |
| 4369 ** [sqlite3_create_module_v2()] with a NULL client data destructor. | |
| 4370 */ | |
| 4371 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_create_module( | |
| 4372 sqlite3 *db, /* SQLite connection to register module with */ | |
| 4373 const char *zName, /* Name of the module */ | |
| 4374 const sqlite3_module *p, /* Methods for the module */ | |
| 4375 void *pClientData /* Client data for xCreate/xConnect */ | |
| 4376 ); | |
| 4377 | |
| 4378 /* | |
| 4379 ** CAPI3REF: Register A Virtual Table Implementation {H18210} <S20400> | |
| 4380 ** EXPERIMENTAL | |
| 4381 ** | |
| 4382 ** This routine is identical to the [sqlite3_create_module()] method, | |
| 4383 ** except that it has an extra parameter to specify | |
| 4384 ** a destructor function for the client data pointer. SQLite will | |
| 4385 ** invoke the destructor function (if it is not NULL) when SQLite | |
| 4386 ** no longer needs the pClientData pointer. | |
| 4387 */ | |
| 4388 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_create_module_v2( | |
| 4389 sqlite3 *db, /* SQLite connection to register module with */ | |
| 4390 const char *zName, /* Name of the module */ | |
| 4391 const sqlite3_module *p, /* Methods for the module */ | |
| 4392 void *pClientData, /* Client data for xCreate/xConnect */ | |
| 4393 void(*xDestroy)(void*) /* Module destructor function */ | |
| 4394 ); | |
| 4395 | |
| 4396 /* | |
| 4397 ** CAPI3REF: Virtual Table Instance Object {H18010} <S20400> | |
| 4398 ** KEYWORDS: sqlite3_vtab | |
| 4399 ** EXPERIMENTAL | |
| 4400 ** | |
| 4401 ** Every [virtual table module] implementation uses a subclass | |
| 4402 ** of the following structure to describe a particular instance | |
| 4403 ** of the [virtual table]. Each subclass will | |
| 4404 ** be tailored to the specific needs of the module implementation. | |
| 4405 ** The purpose of this superclass is to define certain fields that are | |
| 4406 ** common to all module implementations. | |
| 4407 ** | |
| 4408 ** Virtual tables methods can set an error message by assigning a | |
| 4409 ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should | |
| 4410 ** take care that any prior string is freed by a call to [sqlite3_free()] | |
| 4411 ** prior to assigning a new string to zErrMsg. After the error message | |
| 4412 ** is delivered up to the client application, the string will be automatically | |
| 4413 ** freed by sqlite3_free() and the zErrMsg field will be zeroed. | |
| 4414 */ | |
| 4415 struct sqlite3_vtab { | |
| 4416 const sqlite3_module *pModule; /* The module for this virtual table */ | |
| 4417 int nRef; /* NO LONGER USED */ | |
| 4418 char *zErrMsg; /* Error message from sqlite3_mprintf() */ | |
| 4419 /* Virtual table implementations will typically add additional fields */ | |
| 4420 }; | |
| 4421 | |
| 4422 /* | |
| 4423 ** CAPI3REF: Virtual Table Cursor Object {H18020} <S20400> | |
| 4424 ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor} | |
| 4425 ** EXPERIMENTAL | |
| 4426 ** | |
| 4427 ** Every [virtual table module] implementation uses a subclass of the | |
| 4428 ** following structure to describe cursors that point into the | |
| 4429 ** [virtual table] and are used | |
| 4430 ** to loop through the virtual table. Cursors are created using the | |
| 4431 ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed | |
| 4432 ** by the [sqlite3_module.xClose | xClose] method. Cussors are used | |
| 4433 ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods | |
| 4434 ** of the module. Each module implementation will define | |
| 4435 ** the content of a cursor structure to suit its own needs. | |
| 4436 ** | |
| 4437 ** This superclass exists in order to define fields of the cursor that | |
| 4438 ** are common to all implementations. | |
| 4439 */ | |
| 4440 struct sqlite3_vtab_cursor { | |
| 4441 sqlite3_vtab *pVtab; /* Virtual table of this cursor */ | |
| 4442 /* Virtual table implementations will typically add additional fields */ | |
| 4443 }; | |
| 4444 | |
| 4445 /* | |
| 4446 ** CAPI3REF: Declare The Schema Of A Virtual Table {H18280} <S20400> | |
| 4447 ** EXPERIMENTAL | |
| 4448 ** | |
| 4449 ** The [xCreate] and [xConnect] methods of a | |
| 4450 ** [virtual table module] call this interface | |
| 4451 ** to declare the format (the names and datatypes of the columns) of | |
| 4452 ** the virtual tables they implement. | |
| 4453 */ | |
| 4454 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_declare_vtab(sqlite3*, const char *zS
QL); | |
| 4455 | |
| 4456 /* | |
| 4457 ** CAPI3REF: Overload A Function For A Virtual Table {H18300} <S20400> | |
| 4458 ** EXPERIMENTAL | |
| 4459 ** | |
| 4460 ** Virtual tables can provide alternative implementations of functions | |
| 4461 ** using the [xFindFunction] method of the [virtual table module]. | |
| 4462 ** But global versions of those functions | |
| 4463 ** must exist in order to be overloaded. | |
| 4464 ** | |
| 4465 ** This API makes sure a global version of a function with a particular | |
| 4466 ** name and number of parameters exists. If no such function exists | |
| 4467 ** before this API is called, a new function is created. The implementation | |
| 4468 ** of the new function always causes an exception to be thrown. So | |
| 4469 ** the new function is not good for anything by itself. Its only | |
| 4470 ** purpose is to be a placeholder function that can be overloaded | |
| 4471 ** by a [virtual table]. | |
| 4472 */ | |
| 4473 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_overload_function(sqlite3*, const cha
r *zFuncName, int nArg); | |
| 4474 | |
| 4475 /* | |
| 4476 ** The interface to the virtual-table mechanism defined above (back up | |
| 4477 ** to a comment remarkably similar to this one) is currently considered | |
| 4478 ** to be experimental. The interface might change in incompatible ways. | |
| 4479 ** If this is a problem for you, do not use the interface at this time. | |
| 4480 ** | |
| 4481 ** When the virtual-table mechanism stabilizes, we will declare the | |
| 4482 ** interface fixed, support it indefinitely, and remove this comment. | |
| 4483 ** | |
| 4484 ****** EXPERIMENTAL - subject to change without notice ************** | |
| 4485 */ | |
| 4486 | |
| 4487 /* | |
| 4488 ** CAPI3REF: A Handle To An Open BLOB {H17800} <S30230> | |
| 4489 ** KEYWORDS: {BLOB handle} {BLOB handles} | |
| 4490 ** | |
| 4491 ** An instance of this object represents an open BLOB on which | |
| 4492 ** [sqlite3_blob_open | incremental BLOB I/O] can be performed. | |
| 4493 ** Objects of this type are created by [sqlite3_blob_open()] | |
| 4494 ** and destroyed by [sqlite3_blob_close()]. | |
| 4495 ** The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces | |
| 4496 ** can be used to read or write small subsections of the BLOB. | |
| 4497 ** The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes. | |
| 4498 */ | |
| 4499 typedef struct sqlite3_blob sqlite3_blob; | |
| 4500 | |
| 4501 /* | |
| 4502 ** CAPI3REF: Open A BLOB For Incremental I/O {H17810} <S30230> | |
| 4503 ** | |
| 4504 ** This interfaces opens a [BLOB handle | handle] to the BLOB located | |
| 4505 ** in row iRow, column zColumn, table zTable in database zDb; | |
| 4506 ** in other words, the same BLOB that would be selected by: | |
| 4507 ** | |
| 4508 ** <pre> | |
| 4509 ** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow; | |
| 4510 ** </pre> {END} | |
| 4511 ** | |
| 4512 ** If the flags parameter is non-zero, then the BLOB is opened for read | |
| 4513 ** and write access. If it is zero, the BLOB is opened for read access. | |
| 4514 ** | |
| 4515 ** Note that the database name is not the filename that contains | |
| 4516 ** the database but rather the symbolic name of the database that | |
| 4517 ** is assigned when the database is connected using [ATTACH]. | |
| 4518 ** For the main database file, the database name is "main". | |
| 4519 ** For TEMP tables, the database name is "temp". | |
| 4520 ** | |
| 4521 ** On success, [SQLITE_OK] is returned and the new [BLOB handle] is written | |
| 4522 ** to *ppBlob. Otherwise an [error code] is returned and *ppBlob is set | |
| 4523 ** to be a null pointer. | |
| 4524 ** This function sets the [database connection] error code and message | |
| 4525 ** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()] and related | |
| 4526 ** functions. Note that the *ppBlob variable is always initialized in a | |
| 4527 ** way that makes it safe to invoke [sqlite3_blob_close()] on *ppBlob | |
| 4528 ** regardless of the success or failure of this routine. | |
| 4529 ** | |
| 4530 ** If the row that a BLOB handle points to is modified by an | |
| 4531 ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects | |
| 4532 ** then the BLOB handle is marked as "expired". | |
| 4533 ** This is true if any column of the row is changed, even a column | |
| 4534 ** other than the one the BLOB handle is open on. | |
| 4535 ** Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for | |
| 4536 ** a expired BLOB handle fail with an return code of [SQLITE_ABORT]. | |
| 4537 ** Changes written into a BLOB prior to the BLOB expiring are not | |
| 4538 ** rollback by the expiration of the BLOB. Such changes will eventually | |
| 4539 ** commit if the transaction continues to completion. | |
| 4540 ** | |
| 4541 ** Use the [sqlite3_blob_bytes()] interface to determine the size of | |
| 4542 ** the opened blob. The size of a blob may not be changed by this | |
| 4543 ** interface. Use the [UPDATE] SQL command to change the size of a | |
| 4544 ** blob. | |
| 4545 ** | |
| 4546 ** The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces | |
| 4547 ** and the built-in [zeroblob] SQL function can be used, if desired, | |
| 4548 ** to create an empty, zero-filled blob in which to read or write using | |
| 4549 ** this interface. | |
| 4550 ** | |
| 4551 ** To avoid a resource leak, every open [BLOB handle] should eventually | |
| 4552 ** be released by a call to [sqlite3_blob_close()]. | |
| 4553 ** | |
| 4554 ** Requirements: | |
| 4555 ** [H17813] [H17814] [H17816] [H17819] [H17821] [H17824] | |
| 4556 */ | |
| 4557 SQLITE_API int sqlite3_blob_open( | |
| 4558 sqlite3*, | |
| 4559 const char *zDb, | |
| 4560 const char *zTable, | |
| 4561 const char *zColumn, | |
| 4562 sqlite3_int64 iRow, | |
| 4563 int flags, | |
| 4564 sqlite3_blob **ppBlob | |
| 4565 ); | |
| 4566 | |
| 4567 /* | |
| 4568 ** CAPI3REF: Close A BLOB Handle {H17830} <S30230> | |
| 4569 ** | |
| 4570 ** Closes an open [BLOB handle]. | |
| 4571 ** | |
| 4572 ** Closing a BLOB shall cause the current transaction to commit | |
| 4573 ** if there are no other BLOBs, no pending prepared statements, and the | |
| 4574 ** database connection is in [autocommit mode]. | |
| 4575 ** If any writes were made to the BLOB, they might be held in cache | |
| 4576 ** until the close operation if they will fit. | |
| 4577 ** | |
| 4578 ** Closing the BLOB often forces the changes | |
| 4579 ** out to disk and so if any I/O errors occur, they will likely occur | |
| 4580 ** at the time when the BLOB is closed. Any errors that occur during | |
| 4581 ** closing are reported as a non-zero return value. | |
| 4582 ** | |
| 4583 ** The BLOB is closed unconditionally. Even if this routine returns | |
| 4584 ** an error code, the BLOB is still closed. | |
| 4585 ** | |
| 4586 ** Calling this routine with a null pointer (which as would be returned | |
| 4587 ** by failed call to [sqlite3_blob_open()]) is a harmless no-op. | |
| 4588 ** | |
| 4589 ** Requirements: | |
| 4590 ** [H17833] [H17836] [H17839] | |
| 4591 */ | |
| 4592 SQLITE_API int sqlite3_blob_close(sqlite3_blob *); | |
| 4593 | |
| 4594 /* | |
| 4595 ** CAPI3REF: Return The Size Of An Open BLOB {H17840} <S30230> | |
| 4596 ** | |
| 4597 ** Returns the size in bytes of the BLOB accessible via the | |
| 4598 ** successfully opened [BLOB handle] in its only argument. The | |
| 4599 ** incremental blob I/O routines can only read or overwriting existing | |
| 4600 ** blob content; they cannot change the size of a blob. | |
| 4601 ** | |
| 4602 ** This routine only works on a [BLOB handle] which has been created | |
| 4603 ** by a prior successful call to [sqlite3_blob_open()] and which has not | |
| 4604 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in | |
| 4605 ** to this routine results in undefined and probably undesirable behavior. | |
| 4606 ** | |
| 4607 ** Requirements: | |
| 4608 ** [H17843] | |
| 4609 */ | |
| 4610 SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *); | |
| 4611 | |
| 4612 /* | |
| 4613 ** CAPI3REF: Read Data From A BLOB Incrementally {H17850} <S30230> | |
| 4614 ** | |
| 4615 ** This function is used to read data from an open [BLOB handle] into a | |
| 4616 ** caller-supplied buffer. N bytes of data are copied into buffer Z | |
| 4617 ** from the open BLOB, starting at offset iOffset. | |
| 4618 ** | |
| 4619 ** If offset iOffset is less than N bytes from the end of the BLOB, | |
| 4620 ** [SQLITE_ERROR] is returned and no data is read. If N or iOffset is | |
| 4621 ** less than zero, [SQLITE_ERROR] is returned and no data is read. | |
| 4622 ** The size of the blob (and hence the maximum value of N+iOffset) | |
| 4623 ** can be determined using the [sqlite3_blob_bytes()] interface. | |
| 4624 ** | |
| 4625 ** An attempt to read from an expired [BLOB handle] fails with an | |
| 4626 ** error code of [SQLITE_ABORT]. | |
| 4627 ** | |
| 4628 ** On success, SQLITE_OK is returned. | |
| 4629 ** Otherwise, an [error code] or an [extended error code] is returned. | |
| 4630 ** | |
| 4631 ** This routine only works on a [BLOB handle] which has been created | |
| 4632 ** by a prior successful call to [sqlite3_blob_open()] and which has not | |
| 4633 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in | |
| 4634 ** to this routine results in undefined and probably undesirable behavior. | |
| 4635 ** | |
| 4636 ** See also: [sqlite3_blob_write()]. | |
| 4637 ** | |
| 4638 ** Requirements: | |
| 4639 ** [H17853] [H17856] [H17859] [H17862] [H17863] [H17865] [H17868] | |
| 4640 */ | |
| 4641 SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); | |
| 4642 | |
| 4643 /* | |
| 4644 ** CAPI3REF: Write Data Into A BLOB Incrementally {H17870} <S30230> | |
| 4645 ** | |
| 4646 ** This function is used to write data into an open [BLOB handle] from a | |
| 4647 ** caller-supplied buffer. N bytes of data are copied from the buffer Z | |
| 4648 ** into the open BLOB, starting at offset iOffset. | |
| 4649 ** | |
| 4650 ** If the [BLOB handle] passed as the first argument was not opened for | |
| 4651 ** writing (the flags parameter to [sqlite3_blob_open()] was zero), | |
| 4652 ** this function returns [SQLITE_READONLY]. | |
| 4653 ** | |
| 4654 ** This function may only modify the contents of the BLOB; it is | |
| 4655 ** not possible to increase the size of a BLOB using this API. | |
| 4656 ** If offset iOffset is less than N bytes from the end of the BLOB, | |
| 4657 ** [SQLITE_ERROR] is returned and no data is written. If N is | |
| 4658 ** less than zero [SQLITE_ERROR] is returned and no data is written. | |
| 4659 ** The size of the BLOB (and hence the maximum value of N+iOffset) | |
| 4660 ** can be determined using the [sqlite3_blob_bytes()] interface. | |
| 4661 ** | |
| 4662 ** An attempt to write to an expired [BLOB handle] fails with an | |
| 4663 ** error code of [SQLITE_ABORT]. Writes to the BLOB that occurred | |
| 4664 ** before the [BLOB handle] expired are not rolled back by the | |
| 4665 ** expiration of the handle, though of course those changes might | |
| 4666 ** have been overwritten by the statement that expired the BLOB handle | |
| 4667 ** or by other independent statements. | |
| 4668 ** | |
| 4669 ** On success, SQLITE_OK is returned. | |
| 4670 ** Otherwise, an [error code] or an [extended error code] is returned. | |
| 4671 ** | |
| 4672 ** This routine only works on a [BLOB handle] which has been created | |
| 4673 ** by a prior successful call to [sqlite3_blob_open()] and which has not | |
| 4674 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in | |
| 4675 ** to this routine results in undefined and probably undesirable behavior. | |
| 4676 ** | |
| 4677 ** See also: [sqlite3_blob_read()]. | |
| 4678 ** | |
| 4679 ** Requirements: | |
| 4680 ** [H17873] [H17874] [H17875] [H17876] [H17877] [H17879] [H17882] [H17885] | |
| 4681 ** [H17888] | |
| 4682 */ | |
| 4683 SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOff
set); | |
| 4684 | |
| 4685 /* Begin preload-cache.patch for Chromium */ | |
| 4686 /* | |
| 4687 ** Preload the databases into the pager cache, up to the maximum size of the | |
| 4688 ** pager cache. | |
| 4689 ** | |
| 4690 ** For a database to be loaded successfully, the pager must be active. That is, | |
| 4691 ** there must be an open statement on that database. See sqlite3pager_loadall | |
| 4692 ** | |
| 4693 ** There might be many databases attached to the given connection. We iterate | |
| 4694 ** them all and try to load them. If none are loadable successfully, we return | |
| 4695 ** an error. Otherwise, we return OK. | |
| 4696 */ | |
| 4697 int sqlite3Preload(sqlite3 *db); | |
| 4698 /* End preload-cache.patch for Chromium */ | |
| 4699 | |
| 4700 /* | |
| 4701 ** CAPI3REF: Virtual File System Objects {H11200} <S20100> | |
| 4702 ** | |
| 4703 ** A virtual filesystem (VFS) is an [sqlite3_vfs] object | |
| 4704 ** that SQLite uses to interact | |
| 4705 ** with the underlying operating system. Most SQLite builds come with a | |
| 4706 ** single default VFS that is appropriate for the host computer. | |
| 4707 ** New VFSes can be registered and existing VFSes can be unregistered. | |
| 4708 ** The following interfaces are provided. | |
| 4709 ** | |
| 4710 ** The sqlite3_vfs_find() interface returns a pointer to a VFS given its name. | |
| 4711 ** Names are case sensitive. | |
| 4712 ** Names are zero-terminated UTF-8 strings. | |
| 4713 ** If there is no match, a NULL pointer is returned. | |
| 4714 ** If zVfsName is NULL then the default VFS is returned. | |
| 4715 ** | |
| 4716 ** New VFSes are registered with sqlite3_vfs_register(). | |
| 4717 ** Each new VFS becomes the default VFS if the makeDflt flag is set. | |
| 4718 ** The same VFS can be registered multiple times without injury. | |
| 4719 ** To make an existing VFS into the default VFS, register it again | |
| 4720 ** with the makeDflt flag set. If two different VFSes with the | |
| 4721 ** same name are registered, the behavior is undefined. If a | |
| 4722 ** VFS is registered with a name that is NULL or an empty string, | |
| 4723 ** then the behavior is undefined. | |
| 4724 ** | |
| 4725 ** Unregister a VFS with the sqlite3_vfs_unregister() interface. | |
| 4726 ** If the default VFS is unregistered, another VFS is chosen as | |
| 4727 ** the default. The choice for the new VFS is arbitrary. | |
| 4728 ** | |
| 4729 ** Requirements: | |
| 4730 ** [H11203] [H11206] [H11209] [H11212] [H11215] [H11218] | |
| 4731 */ | |
| 4732 SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName); | |
| 4733 SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); | |
| 4734 SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*); | |
| 4735 | |
| 4736 /* | |
| 4737 ** CAPI3REF: Mutexes {H17000} <S20000> | |
| 4738 ** | |
| 4739 ** The SQLite core uses these routines for thread | |
| 4740 ** synchronization. Though they are intended for internal | |
| 4741 ** use by SQLite, code that links against SQLite is | |
| 4742 ** permitted to use any of these routines. | |
| 4743 ** | |
| 4744 ** The SQLite source code contains multiple implementations | |
| 4745 ** of these mutex routines. An appropriate implementation | |
| 4746 ** is selected automatically at compile-time. The following | |
| 4747 ** implementations are available in the SQLite core: | |
| 4748 ** | |
| 4749 ** <ul> | |
| 4750 ** <li> SQLITE_MUTEX_OS2 | |
| 4751 ** <li> SQLITE_MUTEX_PTHREAD | |
| 4752 ** <li> SQLITE_MUTEX_W32 | |
| 4753 ** <li> SQLITE_MUTEX_NOOP | |
| 4754 ** </ul> | |
| 4755 ** | |
| 4756 ** The SQLITE_MUTEX_NOOP implementation is a set of routines | |
| 4757 ** that does no real locking and is appropriate for use in | |
| 4758 ** a single-threaded application. The SQLITE_MUTEX_OS2, | |
| 4759 ** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations | |
| 4760 ** are appropriate for use on OS/2, Unix, and Windows. | |
| 4761 ** | |
| 4762 ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor | |
| 4763 ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex | |
| 4764 ** implementation is included with the library. In this case the | |
| 4765 ** application must supply a custom mutex implementation using the | |
| 4766 ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function | |
| 4767 ** before calling sqlite3_initialize() or any other public sqlite3_ | |
| 4768 ** function that calls sqlite3_initialize(). | |
| 4769 ** | |
| 4770 ** {H17011} The sqlite3_mutex_alloc() routine allocates a new | |
| 4771 ** mutex and returns a pointer to it. {H17012} If it returns NULL | |
| 4772 ** that means that a mutex could not be allocated. {H17013} SQLite | |
| 4773 ** will unwind its stack and return an error. {H17014} The argument | |
| 4774 ** to sqlite3_mutex_alloc() is one of these integer constants: | |
| 4775 ** | |
| 4776 ** <ul> | |
| 4777 ** <li> SQLITE_MUTEX_FAST | |
| 4778 ** <li> SQLITE_MUTEX_RECURSIVE | |
| 4779 ** <li> SQLITE_MUTEX_STATIC_MASTER | |
| 4780 ** <li> SQLITE_MUTEX_STATIC_MEM | |
| 4781 ** <li> SQLITE_MUTEX_STATIC_MEM2 | |
| 4782 ** <li> SQLITE_MUTEX_STATIC_PRNG | |
| 4783 ** <li> SQLITE_MUTEX_STATIC_LRU | |
| 4784 ** <li> SQLITE_MUTEX_STATIC_LRU2 | |
| 4785 ** </ul> | |
| 4786 ** | |
| 4787 ** {H17015} The first two constants cause sqlite3_mutex_alloc() to create | |
| 4788 ** a new mutex. The new mutex is recursive when SQLITE_MUTEX_RECURSIVE | |
| 4789 ** is used but not necessarily so when SQLITE_MUTEX_FAST is used. {END} | |
| 4790 ** The mutex implementation does not need to make a distinction | |
| 4791 ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does | |
| 4792 ** not want to. {H17016} But SQLite will only request a recursive mutex in | |
| 4793 ** cases where it really needs one. {END} If a faster non-recursive mutex | |
| 4794 ** implementation is available on the host platform, the mutex subsystem | |
| 4795 ** might return such a mutex in response to SQLITE_MUTEX_FAST. | |
| 4796 ** | |
| 4797 ** {H17017} The other allowed parameters to sqlite3_mutex_alloc() each return | |
| 4798 ** a pointer to a static preexisting mutex. {END} Six static mutexes are | |
| 4799 ** used by the current version of SQLite. Future versions of SQLite | |
| 4800 ** may add additional static mutexes. Static mutexes are for internal | |
| 4801 ** use by SQLite only. Applications that use SQLite mutexes should | |
| 4802 ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or | |
| 4803 ** SQLITE_MUTEX_RECURSIVE. | |
| 4804 ** | |
| 4805 ** {H17018} Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST | |
| 4806 ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() | |
| 4807 ** returns a different mutex on every call. {H17034} But for the static | |
| 4808 ** mutex types, the same mutex is returned on every call that has | |
| 4809 ** the same type number. | |
| 4810 ** | |
| 4811 ** {H17019} The sqlite3_mutex_free() routine deallocates a previously | |
| 4812 ** allocated dynamic mutex. {H17020} SQLite is careful to deallocate every | |
| 4813 ** dynamic mutex that it allocates. {A17021} The dynamic mutexes must not be in | |
| 4814 ** use when they are deallocated. {A17022} Attempting to deallocate a static | |
| 4815 ** mutex results in undefined behavior. {H17023} SQLite never deallocates | |
| 4816 ** a static mutex. {END} | |
| 4817 ** | |
| 4818 ** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt | |
| 4819 ** to enter a mutex. {H17024} If another thread is already within the mutex, | |
| 4820 ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return | |
| 4821 ** SQLITE_BUSY. {H17025} The sqlite3_mutex_try() interface returns [SQLITE_OK] | |
| 4822 ** upon successful entry. {H17026} Mutexes created using | |
| 4823 ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. | |
| 4824 ** {H17027} In such cases the, | |
| 4825 ** mutex must be exited an equal number of times before another thread | |
| 4826 ** can enter. {A17028} If the same thread tries to enter any other | |
| 4827 ** kind of mutex more than once, the behavior is undefined. | |
| 4828 ** {H17029} SQLite will never exhibit | |
| 4829 ** such behavior in its own use of mutexes. | |
| 4830 ** | |
| 4831 ** Some systems (for example, Windows 95) do not support the operation | |
| 4832 ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() | |
| 4833 ** will always return SQLITE_BUSY. {H17030} The SQLite core only ever uses | |
| 4834 ** sqlite3_mutex_try() as an optimization so this is acceptable behavior. | |
| 4835 ** | |
| 4836 ** {H17031} The sqlite3_mutex_leave() routine exits a mutex that was | |
| 4837 ** previously entered by the same thread. {A17032} The behavior | |
| 4838 ** is undefined if the mutex is not currently entered by the | |
| 4839 ** calling thread or is not currently allocated. {H17033} SQLite will | |
| 4840 ** never do either. {END} | |
| 4841 ** | |
| 4842 ** If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or | |
| 4843 ** sqlite3_mutex_leave() is a NULL pointer, then all three routines | |
| 4844 ** behave as no-ops. | |
| 4845 ** | |
| 4846 ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. | |
| 4847 */ | |
| 4848 SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int); | |
| 4849 SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*); | |
| 4850 SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*); | |
| 4851 SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*); | |
| 4852 SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*); | |
| 4853 | |
| 4854 /* | |
| 4855 ** CAPI3REF: Mutex Methods Object {H17120} <S20130> | |
| 4856 ** EXPERIMENTAL | |
| 4857 ** | |
| 4858 ** An instance of this structure defines the low-level routines | |
| 4859 ** used to allocate and use mutexes. | |
| 4860 ** | |
| 4861 ** Usually, the default mutex implementations provided by SQLite are | |
| 4862 ** sufficient, however the user has the option of substituting a custom | |
| 4863 ** implementation for specialized deployments or systems for which SQLite | |
| 4864 ** does not provide a suitable implementation. In this case, the user | |
| 4865 ** creates and populates an instance of this structure to pass | |
| 4866 ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option. | |
| 4867 ** Additionally, an instance of this structure can be used as an | |
| 4868 ** output variable when querying the system for the current mutex | |
| 4869 ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option. | |
| 4870 ** | |
| 4871 ** The xMutexInit method defined by this structure is invoked as | |
| 4872 ** part of system initialization by the sqlite3_initialize() function. | |
| 4873 ** {H17001} The xMutexInit routine shall be called by SQLite once for each | |
| 4874 ** effective call to [sqlite3_initialize()]. | |
| 4875 ** | |
| 4876 ** The xMutexEnd method defined by this structure is invoked as | |
| 4877 ** part of system shutdown by the sqlite3_shutdown() function. The | |
| 4878 ** implementation of this method is expected to release all outstanding | |
| 4879 ** resources obtained by the mutex methods implementation, especially | |
| 4880 ** those obtained by the xMutexInit method. {H17003} The xMutexEnd() | |
| 4881 ** interface shall be invoked once for each call to [sqlite3_shutdown()]. | |
| 4882 ** | |
| 4883 ** The remaining seven methods defined by this structure (xMutexAlloc, | |
| 4884 ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and | |
| 4885 ** xMutexNotheld) implement the following interfaces (respectively): | |
| 4886 ** | |
| 4887 ** <ul> | |
| 4888 ** <li> [sqlite3_mutex_alloc()] </li> | |
| 4889 ** <li> [sqlite3_mutex_free()] </li> | |
| 4890 ** <li> [sqlite3_mutex_enter()] </li> | |
| 4891 ** <li> [sqlite3_mutex_try()] </li> | |
| 4892 ** <li> [sqlite3_mutex_leave()] </li> | |
| 4893 ** <li> [sqlite3_mutex_held()] </li> | |
| 4894 ** <li> [sqlite3_mutex_notheld()] </li> | |
| 4895 ** </ul> | |
| 4896 ** | |
| 4897 ** The only difference is that the public sqlite3_XXX functions enumerated | |
| 4898 ** above silently ignore any invocations that pass a NULL pointer instead | |
| 4899 ** of a valid mutex handle. The implementations of the methods defined | |
| 4900 ** by this structure are not required to handle this case, the results | |
| 4901 ** of passing a NULL pointer instead of a valid mutex handle are undefined | |
| 4902 ** (i.e. it is acceptable to provide an implementation that segfaults if | |
| 4903 ** it is passed a NULL pointer). | |
| 4904 ** | |
| 4905 ** The xMutexInit() method must be threadsafe. It must be harmless to | |
| 4906 ** invoke xMutexInit() mutiple times within the same process and without | |
| 4907 ** intervening calls to xMutexEnd(). Second and subsequent calls to | |
| 4908 ** xMutexInit() must be no-ops. | |
| 4909 ** | |
| 4910 ** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()] | |
| 4911 ** and its associates). Similarly, xMutexAlloc() must not use SQLite memory | |
| 4912 ** allocation for a static mutex. However xMutexAlloc() may use SQLite | |
| 4913 ** memory allocation for a fast or recursive mutex. | |
| 4914 ** | |
| 4915 ** SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is | |
| 4916 ** called, but only if the prior call to xMutexInit returned SQLITE_OK. | |
| 4917 ** If xMutexInit fails in any way, it is expected to clean up after itself | |
| 4918 ** prior to returning. | |
| 4919 */ | |
| 4920 typedef struct sqlite3_mutex_methods sqlite3_mutex_methods; | |
| 4921 struct sqlite3_mutex_methods { | |
| 4922 int (*xMutexInit)(void); | |
| 4923 int (*xMutexEnd)(void); | |
| 4924 sqlite3_mutex *(*xMutexAlloc)(int); | |
| 4925 void (*xMutexFree)(sqlite3_mutex *); | |
| 4926 void (*xMutexEnter)(sqlite3_mutex *); | |
| 4927 int (*xMutexTry)(sqlite3_mutex *); | |
| 4928 void (*xMutexLeave)(sqlite3_mutex *); | |
| 4929 int (*xMutexHeld)(sqlite3_mutex *); | |
| 4930 int (*xMutexNotheld)(sqlite3_mutex *); | |
| 4931 }; | |
| 4932 | |
| 4933 /* | |
| 4934 ** CAPI3REF: Mutex Verification Routines {H17080} <S20130> <S30800> | |
| 4935 ** | |
| 4936 ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines | |
| 4937 ** are intended for use inside assert() statements. {H17081} The SQLite core | |
| 4938 ** never uses these routines except inside an assert() and applications | |
| 4939 ** are advised to follow the lead of the core. {H17082} The core only | |
| 4940 ** provides implementations for these routines when it is compiled | |
| 4941 ** with the SQLITE_DEBUG flag. {A17087} External mutex implementations | |
| 4942 ** are only required to provide these routines if SQLITE_DEBUG is | |
| 4943 ** defined and if NDEBUG is not defined. | |
| 4944 ** | |
| 4945 ** {H17083} These routines should return true if the mutex in their argument | |
| 4946 ** is held or not held, respectively, by the calling thread. | |
| 4947 ** | |
| 4948 ** {X17084} The implementation is not required to provided versions of these | |
| 4949 ** routines that actually work. If the implementation does not provide working | |
| 4950 ** versions of these routines, it should at least provide stubs that always | |
| 4951 ** return true so that one does not get spurious assertion failures. | |
| 4952 ** | |
| 4953 ** {H17085} If the argument to sqlite3_mutex_held() is a NULL pointer then | |
| 4954 ** the routine should return 1. {END} This seems counter-intuitive since | |
| 4955 ** clearly the mutex cannot be held if it does not exist. But the | |
| 4956 ** the reason the mutex does not exist is because the build is not | |
| 4957 ** using mutexes. And we do not want the assert() containing the | |
| 4958 ** call to sqlite3_mutex_held() to fail, so a non-zero return is | |
| 4959 ** the appropriate thing to do. {H17086} The sqlite3_mutex_notheld() | |
| 4960 ** interface should also return 1 when given a NULL pointer. | |
| 4961 */ | |
| 4962 SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*); | |
| 4963 SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*); | |
| 4964 | |
| 4965 /* | |
| 4966 ** CAPI3REF: Mutex Types {H17001} <H17000> | |
| 4967 ** | |
| 4968 ** The [sqlite3_mutex_alloc()] interface takes a single argument | |
| 4969 ** which is one of these integer constants. | |
| 4970 ** | |
| 4971 ** The set of static mutexes may change from one SQLite release to the | |
| 4972 ** next. Applications that override the built-in mutex logic must be | |
| 4973 ** prepared to accommodate additional static mutexes. | |
| 4974 */ | |
| 4975 #define SQLITE_MUTEX_FAST 0 | |
| 4976 #define SQLITE_MUTEX_RECURSIVE 1 | |
| 4977 #define SQLITE_MUTEX_STATIC_MASTER 2 | |
| 4978 #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ | |
| 4979 #define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */ | |
| 4980 #define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */ | |
| 4981 #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */ | |
| 4982 #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ | |
| 4983 #define SQLITE_MUTEX_STATIC_LRU2 7 /* lru page list */ | |
| 4984 | |
| 4985 /* | |
| 4986 ** CAPI3REF: Retrieve the mutex for a database connection {H17002} <H17000> | |
| 4987 ** | |
| 4988 ** This interface returns a pointer the [sqlite3_mutex] object that | |
| 4989 ** serializes access to the [database connection] given in the argument | |
| 4990 ** when the [threading mode] is Serialized. | |
| 4991 ** If the [threading mode] is Single-thread or Multi-thread then this | |
| 4992 ** routine returns a NULL pointer. | |
| 4993 */ | |
| 4994 SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*); | |
| 4995 | |
| 4996 /* | |
| 4997 ** CAPI3REF: Low-Level Control Of Database Files {H11300} <S30800> | |
| 4998 ** | |
| 4999 ** {H11301} The [sqlite3_file_control()] interface makes a direct call to the | |
| 5000 ** xFileControl method for the [sqlite3_io_methods] object associated | |
| 5001 ** with a particular database identified by the second argument. {H11302} The | |
| 5002 ** name of the database is the name assigned to the database by the | |
| 5003 ** <a href="lang_attach.html">ATTACH</a> SQL command that opened the | |
| 5004 ** database. {H11303} To control the main database file, use the name "main" | |
| 5005 ** or a NULL pointer. {H11304} The third and fourth parameters to this routine | |
| 5006 ** are passed directly through to the second and third parameters of | |
| 5007 ** the xFileControl method. {H11305} The return value of the xFileControl | |
| 5008 ** method becomes the return value of this routine. | |
| 5009 ** | |
| 5010 ** {H11306} If the second parameter (zDbName) does not match the name of any | |
| 5011 ** open database file, then SQLITE_ERROR is returned. {H11307} This error | |
| 5012 ** code is not remembered and will not be recalled by [sqlite3_errcode()] | |
| 5013 ** or [sqlite3_errmsg()]. {A11308} The underlying xFileControl method might | |
| 5014 ** also return SQLITE_ERROR. {A11309} There is no way to distinguish between | |
| 5015 ** an incorrect zDbName and an SQLITE_ERROR return from the underlying | |
| 5016 ** xFileControl method. {END} | |
| 5017 ** | |
| 5018 ** See also: [SQLITE_FCNTL_LOCKSTATE] | |
| 5019 */ | |
| 5020 SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*
); | |
| 5021 | |
| 5022 /* | |
| 5023 ** CAPI3REF: Testing Interface {H11400} <S30800> | |
| 5024 ** | |
| 5025 ** The sqlite3_test_control() interface is used to read out internal | |
| 5026 ** state of SQLite and to inject faults into SQLite for testing | |
| 5027 ** purposes. The first parameter is an operation code that determines | |
| 5028 ** the number, meaning, and operation of all subsequent parameters. | |
| 5029 ** | |
| 5030 ** This interface is not for use by applications. It exists solely | |
| 5031 ** for verifying the correct operation of the SQLite library. Depending | |
| 5032 ** on how the SQLite library is compiled, this interface might not exist. | |
| 5033 ** | |
| 5034 ** The details of the operation codes, their meanings, the parameters | |
| 5035 ** they take, and what they do are all subject to change without notice. | |
| 5036 ** Unlike most of the SQLite API, this function is not guaranteed to | |
| 5037 ** operate consistently from one release to the next. | |
| 5038 */ | |
| 5039 SQLITE_API int sqlite3_test_control(int op, ...); | |
| 5040 | |
| 5041 /* | |
| 5042 ** CAPI3REF: Testing Interface Operation Codes {H11410} <H11400> | |
| 5043 ** | |
| 5044 ** These constants are the valid operation code parameters used | |
| 5045 ** as the first argument to [sqlite3_test_control()]. | |
| 5046 ** | |
| 5047 ** These parameters and their meanings are subject to change | |
| 5048 ** without notice. These values are for testing purposes only. | |
| 5049 ** Applications should not use any of these parameters or the | |
| 5050 ** [sqlite3_test_control()] interface. | |
| 5051 */ | |
| 5052 #define SQLITE_TESTCTRL_PRNG_SAVE 5 | |
| 5053 #define SQLITE_TESTCTRL_PRNG_RESTORE 6 | |
| 5054 #define SQLITE_TESTCTRL_PRNG_RESET 7 | |
| 5055 #define SQLITE_TESTCTRL_BITVEC_TEST 8 | |
| 5056 #define SQLITE_TESTCTRL_FAULT_INSTALL 9 | |
| 5057 #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10 | |
| 5058 #define SQLITE_TESTCTRL_PENDING_BYTE 11 | |
| 5059 #define SQLITE_TESTCTRL_ASSERT 12 | |
| 5060 #define SQLITE_TESTCTRL_ALWAYS 13 | |
| 5061 #define SQLITE_TESTCTRL_RESERVE 14 | |
| 5062 | |
| 5063 /* | |
| 5064 ** CAPI3REF: SQLite Runtime Status {H17200} <S60200> | |
| 5065 ** EXPERIMENTAL | |
| 5066 ** | |
| 5067 ** This interface is used to retrieve runtime status information | |
| 5068 ** about the preformance of SQLite, and optionally to reset various | |
| 5069 ** highwater marks. The first argument is an integer code for | |
| 5070 ** the specific parameter to measure. Recognized integer codes | |
| 5071 ** are of the form [SQLITE_STATUS_MEMORY_USED | SQLITE_STATUS_...]. | |
| 5072 ** The current value of the parameter is returned into *pCurrent. | |
| 5073 ** The highest recorded value is returned in *pHighwater. If the | |
| 5074 ** resetFlag is true, then the highest record value is reset after | |
| 5075 ** *pHighwater is written. Some parameters do not record the highest | |
| 5076 ** value. For those parameters | |
| 5077 ** nothing is written into *pHighwater and the resetFlag is ignored. | |
| 5078 ** Other parameters record only the highwater mark and not the current | |
| 5079 ** value. For these latter parameters nothing is written into *pCurrent. | |
| 5080 ** | |
| 5081 ** This routine returns SQLITE_OK on success and a non-zero | |
| 5082 ** [error code] on failure. | |
| 5083 ** | |
| 5084 ** This routine is threadsafe but is not atomic. This routine can be | |
| 5085 ** called while other threads are running the same or different SQLite | |
| 5086 ** interfaces. However the values returned in *pCurrent and | |
| 5087 ** *pHighwater reflect the status of SQLite at different points in time | |
| 5088 ** and it is possible that another thread might change the parameter | |
| 5089 ** in between the times when *pCurrent and *pHighwater are written. | |
| 5090 ** | |
| 5091 ** See also: [sqlite3_db_status()] | |
| 5092 */ | |
| 5093 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_status(int op, int *pCurrent, int *pH
ighwater, int resetFlag); | |
| 5094 | |
| 5095 | |
| 5096 /* | |
| 5097 ** CAPI3REF: Status Parameters {H17250} <H17200> | |
| 5098 ** EXPERIMENTAL | |
| 5099 ** | |
| 5100 ** These integer constants designate various run-time status parameters | |
| 5101 ** that can be returned by [sqlite3_status()]. | |
| 5102 ** | |
| 5103 ** <dl> | |
| 5104 ** <dt>SQLITE_STATUS_MEMORY_USED</dt> | |
| 5105 ** <dd>This parameter is the current amount of memory checked out | |
| 5106 ** using [sqlite3_malloc()], either directly or indirectly. The | |
| 5107 ** figure includes calls made to [sqlite3_malloc()] by the application | |
| 5108 ** and internal memory usage by the SQLite library. Scratch memory | |
| 5109 ** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache | |
| 5110 ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in | |
| 5111 ** this parameter. The amount returned is the sum of the allocation | |
| 5112 ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd> | |
| 5113 ** | |
| 5114 ** <dt>SQLITE_STATUS_MALLOC_SIZE</dt> | |
| 5115 ** <dd>This parameter records the largest memory allocation request | |
| 5116 ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their | |
| 5117 ** internal equivalents). Only the value returned in the | |
| 5118 ** *pHighwater parameter to [sqlite3_status()] is of interest. | |
| 5119 ** The value written into the *pCurrent parameter is undefined.</dd> | |
| 5120 ** | |
| 5121 ** <dt>SQLITE_STATUS_PAGECACHE_USED</dt> | |
| 5122 ** <dd>This parameter returns the number of pages used out of the | |
| 5123 ** [pagecache memory allocator] that was configured using | |
| 5124 ** [SQLITE_CONFIG_PAGECACHE]. The | |
| 5125 ** value returned is in pages, not in bytes.</dd> | |
| 5126 ** | |
| 5127 ** <dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt> | |
| 5128 ** <dd>This parameter returns the number of bytes of page cache | |
| 5129 ** allocation which could not be statisfied by the [SQLITE_CONFIG_PAGECACHE] | |
| 5130 ** buffer and where forced to overflow to [sqlite3_malloc()]. The | |
| 5131 ** returned value includes allocations that overflowed because they | |
| 5132 ** where too large (they were larger than the "sz" parameter to | |
| 5133 ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because | |
| 5134 ** no space was left in the page cache.</dd> | |
| 5135 ** | |
| 5136 ** <dt>SQLITE_STATUS_PAGECACHE_SIZE</dt> | |
| 5137 ** <dd>This parameter records the largest memory allocation request | |
| 5138 ** handed to [pagecache memory allocator]. Only the value returned in the | |
| 5139 ** *pHighwater parameter to [sqlite3_status()] is of interest. | |
| 5140 ** The value written into the *pCurrent parameter is undefined.</dd> | |
| 5141 ** | |
| 5142 ** <dt>SQLITE_STATUS_SCRATCH_USED</dt> | |
| 5143 ** <dd>This parameter returns the number of allocations used out of the | |
| 5144 ** [scratch memory allocator] configured using | |
| 5145 ** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not | |
| 5146 ** in bytes. Since a single thread may only have one scratch allocation | |
| 5147 ** outstanding at time, this parameter also reports the number of threads | |
| 5148 ** using scratch memory at the same time.</dd> | |
| 5149 ** | |
| 5150 ** <dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt> | |
| 5151 ** <dd>This parameter returns the number of bytes of scratch memory | |
| 5152 ** allocation which could not be statisfied by the [SQLITE_CONFIG_SCRATCH] | |
| 5153 ** buffer and where forced to overflow to [sqlite3_malloc()]. The values | |
| 5154 ** returned include overflows because the requested allocation was too | |
| 5155 ** larger (that is, because the requested allocation was larger than the | |
| 5156 ** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer | |
| 5157 ** slots were available. | |
| 5158 ** </dd> | |
| 5159 ** | |
| 5160 ** <dt>SQLITE_STATUS_SCRATCH_SIZE</dt> | |
| 5161 ** <dd>This parameter records the largest memory allocation request | |
| 5162 ** handed to [scratch memory allocator]. Only the value returned in the | |
| 5163 ** *pHighwater parameter to [sqlite3_status()] is of interest. | |
| 5164 ** The value written into the *pCurrent parameter is undefined.</dd> | |
| 5165 ** | |
| 5166 ** <dt>SQLITE_STATUS_PARSER_STACK</dt> | |
| 5167 ** <dd>This parameter records the deepest parser stack. It is only | |
| 5168 ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd> | |
| 5169 ** </dl> | |
| 5170 ** | |
| 5171 ** New status parameters may be added from time to time. | |
| 5172 */ | |
| 5173 #define SQLITE_STATUS_MEMORY_USED 0 | |
| 5174 #define SQLITE_STATUS_PAGECACHE_USED 1 | |
| 5175 #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2 | |
| 5176 #define SQLITE_STATUS_SCRATCH_USED 3 | |
| 5177 #define SQLITE_STATUS_SCRATCH_OVERFLOW 4 | |
| 5178 #define SQLITE_STATUS_MALLOC_SIZE 5 | |
| 5179 #define SQLITE_STATUS_PARSER_STACK 6 | |
| 5180 #define SQLITE_STATUS_PAGECACHE_SIZE 7 | |
| 5181 #define SQLITE_STATUS_SCRATCH_SIZE 8 | |
| 5182 | |
| 5183 /* | |
| 5184 ** CAPI3REF: Database Connection Status {H17500} <S60200> | |
| 5185 ** EXPERIMENTAL | |
| 5186 ** | |
| 5187 ** This interface is used to retrieve runtime status information | |
| 5188 ** about a single [database connection]. The first argument is the | |
| 5189 ** database connection object to be interrogated. The second argument | |
| 5190 ** is the parameter to interrogate. Currently, the only allowed value | |
| 5191 ** for the second parameter is [SQLITE_DBSTATUS_LOOKASIDE_USED]. | |
| 5192 ** Additional options will likely appear in future releases of SQLite. | |
| 5193 ** | |
| 5194 ** The current value of the requested parameter is written into *pCur | |
| 5195 ** and the highest instantaneous value is written into *pHiwtr. If | |
| 5196 ** the resetFlg is true, then the highest instantaneous value is | |
| 5197 ** reset back down to the current value. | |
| 5198 ** | |
| 5199 ** See also: [sqlite3_status()] and [sqlite3_stmt_status()]. | |
| 5200 */ | |
| 5201 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_db_status(sqlite3*, int op, int *pCur
, int *pHiwtr, int resetFlg); | |
| 5202 | |
| 5203 /* | |
| 5204 ** CAPI3REF: Status Parameters for database connections {H17520} <H17500> | |
| 5205 ** EXPERIMENTAL | |
| 5206 ** | |
| 5207 ** These constants are the available integer "verbs" that can be passed as | |
| 5208 ** the second argument to the [sqlite3_db_status()] interface. | |
| 5209 ** | |
| 5210 ** New verbs may be added in future releases of SQLite. Existing verbs | |
| 5211 ** might be discontinued. Applications should check the return code from | |
| 5212 ** [sqlite3_db_status()] to make sure that the call worked. | |
| 5213 ** The [sqlite3_db_status()] interface will return a non-zero error code | |
| 5214 ** if a discontinued or unsupported verb is invoked. | |
| 5215 ** | |
| 5216 ** <dl> | |
| 5217 ** <dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt> | |
| 5218 ** <dd>This parameter returns the number of lookaside memory slots currently | |
| 5219 ** checked out.</dd> | |
| 5220 ** </dl> | |
| 5221 */ | |
| 5222 #define SQLITE_DBSTATUS_LOOKASIDE_USED 0 | |
| 5223 | |
| 5224 | |
| 5225 /* | |
| 5226 ** CAPI3REF: Prepared Statement Status {H17550} <S60200> | |
| 5227 ** EXPERIMENTAL | |
| 5228 ** | |
| 5229 ** Each prepared statement maintains various | |
| 5230 ** [SQLITE_STMTSTATUS_SORT | counters] that measure the number | |
| 5231 ** of times it has performed specific operations. These counters can | |
| 5232 ** be used to monitor the performance characteristics of the prepared | |
| 5233 ** statements. For example, if the number of table steps greatly exceeds | |
| 5234 ** the number of table searches or result rows, that would tend to indicate | |
| 5235 ** that the prepared statement is using a full table scan rather than | |
| 5236 ** an index. | |
| 5237 ** | |
| 5238 ** This interface is used to retrieve and reset counter values from | |
| 5239 ** a [prepared statement]. The first argument is the prepared statement | |
| 5240 ** object to be interrogated. The second argument | |
| 5241 ** is an integer code for a specific [SQLITE_STMTSTATUS_SORT | counter] | |
| 5242 ** to be interrogated. | |
| 5243 ** The current value of the requested counter is returned. | |
| 5244 ** If the resetFlg is true, then the counter is reset to zero after this | |
| 5245 ** interface call returns. | |
| 5246 ** | |
| 5247 ** See also: [sqlite3_status()] and [sqlite3_db_status()]. | |
| 5248 */ | |
| 5249 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_stmt_status(sqlite3_stmt*, int op,int
resetFlg); | |
| 5250 | |
| 5251 /* | |
| 5252 ** CAPI3REF: Status Parameters for prepared statements {H17570} <H17550> | |
| 5253 ** EXPERIMENTAL | |
| 5254 ** | |
| 5255 ** These preprocessor macros define integer codes that name counter | |
| 5256 ** values associated with the [sqlite3_stmt_status()] interface. | |
| 5257 ** The meanings of the various counters are as follows: | |
| 5258 ** | |
| 5259 ** <dl> | |
| 5260 ** <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt> | |
| 5261 ** <dd>This is the number of times that SQLite has stepped forward in | |
| 5262 ** a table as part of a full table scan. Large numbers for this counter | |
| 5263 ** may indicate opportunities for performance improvement through | |
| 5264 ** careful use of indices.</dd> | |
| 5265 ** | |
| 5266 ** <dt>SQLITE_STMTSTATUS_SORT</dt> | |
| 5267 ** <dd>This is the number of sort operations that have occurred. | |
| 5268 ** A non-zero value in this counter may indicate an opportunity to | |
| 5269 ** improvement performance through careful use of indices.</dd> | |
| 5270 ** | |
| 5271 ** </dl> | |
| 5272 */ | |
| 5273 #define SQLITE_STMTSTATUS_FULLSCAN_STEP 1 | |
| 5274 #define SQLITE_STMTSTATUS_SORT 2 | |
| 5275 | |
| 5276 /* | |
| 5277 ** CAPI3REF: Custom Page Cache Object | |
| 5278 ** EXPERIMENTAL | |
| 5279 ** | |
| 5280 ** The sqlite3_pcache type is opaque. It is implemented by | |
| 5281 ** the pluggable module. The SQLite core has no knowledge of | |
| 5282 ** its size or internal structure and never deals with the | |
| 5283 ** sqlite3_pcache object except by holding and passing pointers | |
| 5284 ** to the object. | |
| 5285 ** | |
| 5286 ** See [sqlite3_pcache_methods] for additional information. | |
| 5287 */ | |
| 5288 typedef struct sqlite3_pcache sqlite3_pcache; | |
| 5289 | |
| 5290 /* | |
| 5291 ** CAPI3REF: Application Defined Page Cache. | |
| 5292 ** KEYWORDS: {page cache} | |
| 5293 ** EXPERIMENTAL | |
| 5294 ** | |
| 5295 ** The [sqlite3_config]([SQLITE_CONFIG_PCACHE], ...) interface can | |
| 5296 ** register an alternative page cache implementation by passing in an | |
| 5297 ** instance of the sqlite3_pcache_methods structure. The majority of the | |
| 5298 ** heap memory used by SQLite is used by the page cache to cache data read | |
| 5299 ** from, or ready to be written to, the database file. By implementing a | |
| 5300 ** custom page cache using this API, an application can control more | |
| 5301 ** precisely the amount of memory consumed by SQLite, the way in which | |
| 5302 ** that memory is allocated and released, and the policies used to | |
| 5303 ** determine exactly which parts of a database file are cached and for | |
| 5304 ** how long. | |
| 5305 ** | |
| 5306 ** The contents of the sqlite3_pcache_methods structure are copied to an | |
| 5307 ** internal buffer by SQLite within the call to [sqlite3_config]. Hence | |
| 5308 ** the application may discard the parameter after the call to | |
| 5309 ** [sqlite3_config()] returns. | |
| 5310 ** | |
| 5311 ** The xInit() method is called once for each call to [sqlite3_initialize()] | |
| 5312 ** (usually only once during the lifetime of the process). It is passed | |
| 5313 ** a copy of the sqlite3_pcache_methods.pArg value. It can be used to set | |
| 5314 ** up global structures and mutexes required by the custom page cache | |
| 5315 ** implementation. | |
| 5316 ** | |
| 5317 ** The xShutdown() method is called from within [sqlite3_shutdown()], | |
| 5318 ** if the application invokes this API. It can be used to clean up | |
| 5319 ** any outstanding resources before process shutdown, if required. | |
| 5320 ** | |
| 5321 ** SQLite holds a [SQLITE_MUTEX_RECURSIVE] mutex when it invokes | |
| 5322 ** the xInit method, so the xInit method need not be threadsafe. The | |
| 5323 ** xShutdown method is only called from [sqlite3_shutdown()] so it does | |
| 5324 ** not need to be threadsafe either. All other methods must be threadsafe | |
| 5325 ** in multithreaded applications. | |
| 5326 ** | |
| 5327 ** SQLite will never invoke xInit() more than once without an intervening | |
| 5328 ** call to xShutdown(). | |
| 5329 ** | |
| 5330 ** The xCreate() method is used to construct a new cache instance. SQLite | |
| 5331 ** will typically create one cache instance for each open database file, | |
| 5332 ** though this is not guaranteed. The | |
| 5333 ** first parameter, szPage, is the size in bytes of the pages that must | |
| 5334 ** be allocated by the cache. szPage will not be a power of two. szPage | |
| 5335 ** will the page size of the database file that is to be cached plus an | |
| 5336 ** increment (here called "R") of about 100 or 200. SQLite will use the | |
| 5337 ** extra R bytes on each page to store metadata about the underlying | |
| 5338 ** database page on disk. The value of R depends | |
| 5339 ** on the SQLite version, the target platform, and how SQLite was compiled. | |
| 5340 ** R is constant for a particular build of SQLite. The second argument to | |
| 5341 ** xCreate(), bPurgeable, is true if the cache being created will | |
| 5342 ** be used to cache database pages of a file stored on disk, or | |
| 5343 ** false if it is used for an in-memory database. The cache implementation | |
| 5344 ** does not have to do anything special based with the value of bPurgeable; | |
| 5345 ** it is purely advisory. On a cache where bPurgeable is false, SQLite will | |
| 5346 ** never invoke xUnpin() except to deliberately delete a page. | |
| 5347 ** In other words, a cache created with bPurgeable set to false will | |
| 5348 ** never contain any unpinned pages. | |
| 5349 ** | |
| 5350 ** The xCachesize() method may be called at any time by SQLite to set the | |
| 5351 ** suggested maximum cache-size (number of pages stored by) the cache | |
| 5352 ** instance passed as the first argument. This is the value configured using | |
| 5353 ** the SQLite "[PRAGMA cache_size]" command. As with the bPurgeable parameter, | |
| 5354 ** the implementation is not required to do anything with this | |
| 5355 ** value; it is advisory only. | |
| 5356 ** | |
| 5357 ** The xPagecount() method should return the number of pages currently | |
| 5358 ** stored in the cache. | |
| 5359 ** | |
| 5360 ** The xFetch() method is used to fetch a page and return a pointer to it. | |
| 5361 ** A 'page', in this context, is a buffer of szPage bytes aligned at an | |
| 5362 ** 8-byte boundary. The page to be fetched is determined by the key. The | |
| 5363 ** mimimum key value is 1. After it has been retrieved using xFetch, the page | |
| 5364 ** is considered to be "pinned". | |
| 5365 ** | |
| 5366 ** If the requested page is already in the page cache, then the page cache | |
| 5367 ** implementation must return a pointer to the page buffer with its content | |
| 5368 ** intact. If the requested page is not already in the cache, then the | |
| 5369 ** behavior of the cache implementation is determined by the value of the | |
| 5370 ** createFlag parameter passed to xFetch, according to the following table: | |
| 5371 ** | |
| 5372 ** <table border=1 width=85% align=center> | |
| 5373 ** <tr><th> createFlag <th> Behaviour when page is not already in cache | |
| 5374 ** <tr><td> 0 <td> Do not allocate a new page. Return NULL. | |
| 5375 ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so. | |
| 5376 ** Otherwise return NULL. | |
| 5377 ** <tr><td> 2 <td> Make every effort to allocate a new page. Only return | |
| 5378 ** NULL if allocating a new page is effectively impossible. | |
| 5379 ** </table> | |
| 5380 ** | |
| 5381 ** SQLite will normally invoke xFetch() with a createFlag of 0 or 1. If | |
| 5382 ** a call to xFetch() with createFlag==1 returns NULL, then SQLite will | |
| 5383 ** attempt to unpin one or more cache pages by spilling the content of | |
| 5384 ** pinned pages to disk and synching the operating system disk cache. After | |
| 5385 ** attempting to unpin pages, the xFetch() method will be invoked again with | |
| 5386 ** a createFlag of 2. | |
| 5387 ** | |
| 5388 ** xUnpin() is called by SQLite with a pointer to a currently pinned page | |
| 5389 ** as its second argument. If the third parameter, discard, is non-zero, | |
| 5390 ** then the page should be evicted from the cache. In this case SQLite | |
| 5391 ** assumes that the next time the page is retrieved from the cache using | |
| 5392 ** the xFetch() method, it will be zeroed. If the discard parameter is | |
| 5393 ** zero, then the page is considered to be unpinned. The cache implementation | |
| 5394 ** may choose to evict unpinned pages at any time. | |
| 5395 ** | |
| 5396 ** The cache is not required to perform any reference counting. A single | |
| 5397 ** call to xUnpin() unpins the page regardless of the number of prior calls | |
| 5398 ** to xFetch(). | |
| 5399 ** | |
| 5400 ** The xRekey() method is used to change the key value associated with the | |
| 5401 ** page passed as the second argument from oldKey to newKey. If the cache | |
| 5402 ** previously contains an entry associated with newKey, it should be | |
| 5403 ** discarded. Any prior cache entry associated with newKey is guaranteed not | |
| 5404 ** to be pinned. | |
| 5405 ** | |
| 5406 ** When SQLite calls the xTruncate() method, the cache must discard all | |
| 5407 ** existing cache entries with page numbers (keys) greater than or equal | |
| 5408 ** to the value of the iLimit parameter passed to xTruncate(). If any | |
| 5409 ** of these pages are pinned, they are implicitly unpinned, meaning that | |
| 5410 ** they can be safely discarded. | |
| 5411 ** | |
| 5412 ** The xDestroy() method is used to delete a cache allocated by xCreate(). | |
| 5413 ** All resources associated with the specified cache should be freed. After | |
| 5414 ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*] | |
| 5415 ** handle invalid, and will not use it with any other sqlite3_pcache_methods | |
| 5416 ** functions. | |
| 5417 */ | |
| 5418 typedef struct sqlite3_pcache_methods sqlite3_pcache_methods; | |
| 5419 struct sqlite3_pcache_methods { | |
| 5420 void *pArg; | |
| 5421 int (*xInit)(void*); | |
| 5422 void (*xShutdown)(void*); | |
| 5423 sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable); | |
| 5424 void (*xCachesize)(sqlite3_pcache*, int nCachesize); | |
| 5425 int (*xPagecount)(sqlite3_pcache*); | |
| 5426 void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); | |
| 5427 void (*xUnpin)(sqlite3_pcache*, void*, int discard); | |
| 5428 void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey); | |
| 5429 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); | |
| 5430 void (*xDestroy)(sqlite3_pcache*); | |
| 5431 }; | |
| 5432 | |
| 5433 /* | |
| 5434 ** CAPI3REF: Online Backup Object | |
| 5435 ** EXPERIMENTAL | |
| 5436 ** | |
| 5437 ** The sqlite3_backup object records state information about an ongoing | |
| 5438 ** online backup operation. The sqlite3_backup object is created by | |
| 5439 ** a call to [sqlite3_backup_init()] and is destroyed by a call to | |
| 5440 ** [sqlite3_backup_finish()]. | |
| 5441 ** | |
| 5442 ** See Also: [Using the SQLite Online Backup API] | |
| 5443 */ | |
| 5444 typedef struct sqlite3_backup sqlite3_backup; | |
| 5445 | |
| 5446 /* | |
| 5447 ** CAPI3REF: Online Backup API. | |
| 5448 ** EXPERIMENTAL | |
| 5449 ** | |
| 5450 ** This API is used to overwrite the contents of one database with that | |
| 5451 ** of another. It is useful either for creating backups of databases or | |
| 5452 ** for copying in-memory databases to or from persistent files. | |
| 5453 ** | |
| 5454 ** See Also: [Using the SQLite Online Backup API] | |
| 5455 ** | |
| 5456 ** Exclusive access is required to the destination database for the | |
| 5457 ** duration of the operation. However the source database is only | |
| 5458 ** read-locked while it is actually being read, it is not locked | |
| 5459 ** continuously for the entire operation. Thus, the backup may be | |
| 5460 ** performed on a live database without preventing other users from | |
| 5461 ** writing to the database for an extended period of time. | |
| 5462 ** | |
| 5463 ** To perform a backup operation: | |
| 5464 ** <ol> | |
| 5465 ** <li><b>sqlite3_backup_init()</b> is called once to initialize the | |
| 5466 ** backup, | |
| 5467 ** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer | |
| 5468 ** the data between the two databases, and finally | |
| 5469 ** <li><b>sqlite3_backup_finish()</b> is called to release all resources | |
| 5470 ** associated with the backup operation. | |
| 5471 ** </ol> | |
| 5472 ** There should be exactly one call to sqlite3_backup_finish() for each | |
| 5473 ** successful call to sqlite3_backup_init(). | |
| 5474 ** | |
| 5475 ** <b>sqlite3_backup_init()</b> | |
| 5476 ** | |
| 5477 ** The first two arguments passed to [sqlite3_backup_init()] are the database | |
| 5478 ** handle associated with the destination database and the database name | |
| 5479 ** used to attach the destination database to the handle. The database name | |
| 5480 ** is "main" for the main database, "temp" for the temporary database, or | |
| 5481 ** the name specified as part of the [ATTACH] statement if the destination is | |
| 5482 ** an attached database. The third and fourth arguments passed to | |
| 5483 ** sqlite3_backup_init() identify the [database connection] | |
| 5484 ** and database name used | |
| 5485 ** to access the source database. The values passed for the source and | |
| 5486 ** destination [database connection] parameters must not be the same. | |
| 5487 ** | |
| 5488 ** If an error occurs within sqlite3_backup_init(), then NULL is returned | |
| 5489 ** and an error code and error message written into the [database connection] | |
| 5490 ** passed as the first argument. They may be retrieved using the | |
| 5491 ** [sqlite3_errcode()], [sqlite3_errmsg()], and [sqlite3_errmsg16()] functions. | |
| 5492 ** Otherwise, if successful, a pointer to an [sqlite3_backup] object is | |
| 5493 ** returned. This pointer may be used with the sqlite3_backup_step() and | |
| 5494 ** sqlite3_backup_finish() functions to perform the specified backup | |
| 5495 ** operation. | |
| 5496 ** | |
| 5497 ** <b>sqlite3_backup_step()</b> | |
| 5498 ** | |
| 5499 ** Function [sqlite3_backup_step()] is used to copy up to nPage pages between | |
| 5500 ** the source and destination databases, where nPage is the value of the | |
| 5501 ** second parameter passed to sqlite3_backup_step(). If nPage is a negative | |
| 5502 ** value, all remaining source pages are copied. If the required pages are | |
| 5503 ** succesfully copied, but there are still more pages to copy before the | |
| 5504 ** backup is complete, it returns [SQLITE_OK]. If no error occured and there | |
| 5505 ** are no more pages to copy, then [SQLITE_DONE] is returned. If an error | |
| 5506 ** occurs, then an SQLite error code is returned. As well as [SQLITE_OK] and | |
| 5507 ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY], | |
| 5508 ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an | |
| 5509 ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code. | |
| 5510 ** | |
| 5511 ** As well as the case where the destination database file was opened for | |
| 5512 ** read-only access, sqlite3_backup_step() may return [SQLITE_READONLY] if | |
| 5513 ** the destination is an in-memory database with a different page size | |
| 5514 ** from the source database. | |
| 5515 ** | |
| 5516 ** If sqlite3_backup_step() cannot obtain a required file-system lock, then | |
| 5517 ** the [sqlite3_busy_handler | busy-handler function] | |
| 5518 ** is invoked (if one is specified). If the | |
| 5519 ** busy-handler returns non-zero before the lock is available, then | |
| 5520 ** [SQLITE_BUSY] is returned to the caller. In this case the call to | |
| 5521 ** sqlite3_backup_step() can be retried later. If the source | |
| 5522 ** [database connection] | |
| 5523 ** is being used to write to the source database when sqlite3_backup_step() | |
| 5524 ** is called, then [SQLITE_LOCKED] is returned immediately. Again, in this | |
| 5525 ** case the call to sqlite3_backup_step() can be retried later on. If | |
| 5526 ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or | |
| 5527 ** [SQLITE_READONLY] is returned, then | |
| 5528 ** there is no point in retrying the call to sqlite3_backup_step(). These | |
| 5529 ** errors are considered fatal. At this point the application must accept | |
| 5530 ** that the backup operation has failed and pass the backup operation handle | |
| 5531 ** to the sqlite3_backup_finish() to release associated resources. | |
| 5532 ** | |
| 5533 ** Following the first call to sqlite3_backup_step(), an exclusive lock is | |
| 5534 ** obtained on the destination file. It is not released until either | |
| 5535 ** sqlite3_backup_finish() is called or the backup operation is complete | |
| 5536 ** and sqlite3_backup_step() returns [SQLITE_DONE]. Additionally, each time | |
| 5537 ** a call to sqlite3_backup_step() is made a [shared lock] is obtained on | |
| 5538 ** the source database file. This lock is released before the | |
| 5539 ** sqlite3_backup_step() call returns. Because the source database is not | |
| 5540 ** locked between calls to sqlite3_backup_step(), it may be modified mid-way | |
| 5541 ** through the backup procedure. If the source database is modified by an | |
| 5542 ** external process or via a database connection other than the one being | |
| 5543 ** used by the backup operation, then the backup will be transparently | |
| 5544 ** restarted by the next call to sqlite3_backup_step(). If the source | |
| 5545 ** database is modified by the using the same database connection as is used | |
| 5546 ** by the backup operation, then the backup database is transparently | |
| 5547 ** updated at the same time. | |
| 5548 ** | |
| 5549 ** <b>sqlite3_backup_finish()</b> | |
| 5550 ** | |
| 5551 ** Once sqlite3_backup_step() has returned [SQLITE_DONE], or when the | |
| 5552 ** application wishes to abandon the backup operation, the [sqlite3_backup] | |
| 5553 ** object should be passed to sqlite3_backup_finish(). This releases all | |
| 5554 ** resources associated with the backup operation. If sqlite3_backup_step() | |
| 5555 ** has not yet returned [SQLITE_DONE], then any active write-transaction on the | |
| 5556 ** destination database is rolled back. The [sqlite3_backup] object is invalid | |
| 5557 ** and may not be used following a call to sqlite3_backup_finish(). | |
| 5558 ** | |
| 5559 ** The value returned by sqlite3_backup_finish is [SQLITE_OK] if no error | |
| 5560 ** occurred, regardless or whether or not sqlite3_backup_step() was called | |
| 5561 ** a sufficient number of times to complete the backup operation. Or, if | |
| 5562 ** an out-of-memory condition or IO error occured during a call to | |
| 5563 ** sqlite3_backup_step() then [SQLITE_NOMEM] or an | |
| 5564 ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] error code | |
| 5565 ** is returned. In this case the error code and an error message are | |
| 5566 ** written to the destination [database connection]. | |
| 5567 ** | |
| 5568 ** A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() is | |
| 5569 ** not a permanent error and does not affect the return value of | |
| 5570 ** sqlite3_backup_finish(). | |
| 5571 ** | |
| 5572 ** <b>sqlite3_backup_remaining(), sqlite3_backup_pagecount()</b> | |
| 5573 ** | |
| 5574 ** Each call to sqlite3_backup_step() sets two values stored internally | |
| 5575 ** by an [sqlite3_backup] object. The number of pages still to be backed | |
| 5576 ** up, which may be queried by sqlite3_backup_remaining(), and the total | |
| 5577 ** number of pages in the source database file, which may be queried by | |
| 5578 ** sqlite3_backup_pagecount(). | |
| 5579 ** | |
| 5580 ** The values returned by these functions are only updated by | |
| 5581 ** sqlite3_backup_step(). If the source database is modified during a backup | |
| 5582 ** operation, then the values are not updated to account for any extra | |
| 5583 ** pages that need to be updated or the size of the source database file | |
| 5584 ** changing. | |
| 5585 ** | |
| 5586 ** <b>Concurrent Usage of Database Handles</b> | |
| 5587 ** | |
| 5588 ** The source [database connection] may be used by the application for other | |
| 5589 ** purposes while a backup operation is underway or being initialized. | |
| 5590 ** If SQLite is compiled and configured to support threadsafe database | |
| 5591 ** connections, then the source database connection may be used concurrently | |
| 5592 ** from within other threads. | |
| 5593 ** | |
| 5594 ** However, the application must guarantee that the destination database | |
| 5595 ** connection handle is not passed to any other API (by any thread) after | |
| 5596 ** sqlite3_backup_init() is called and before the corresponding call to | |
| 5597 ** sqlite3_backup_finish(). Unfortunately SQLite does not currently check | |
| 5598 ** for this, if the application does use the destination [database connection] | |
| 5599 ** for some other purpose during a backup operation, things may appear to | |
| 5600 ** work correctly but in fact be subtly malfunctioning. Use of the | |
| 5601 ** destination database connection while a backup is in progress might | |
| 5602 ** also cause a mutex deadlock. | |
| 5603 ** | |
| 5604 ** Furthermore, if running in [shared cache mode], the application must | |
| 5605 ** guarantee that the shared cache used by the destination database | |
| 5606 ** is not accessed while the backup is running. In practice this means | |
| 5607 ** that the application must guarantee that the file-system file being | |
| 5608 ** backed up to is not accessed by any connection within the process, | |
| 5609 ** not just the specific connection that was passed to sqlite3_backup_init(). | |
| 5610 ** | |
| 5611 ** The [sqlite3_backup] object itself is partially threadsafe. Multiple | |
| 5612 ** threads may safely make multiple concurrent calls to sqlite3_backup_step(). | |
| 5613 ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount() | |
| 5614 ** APIs are not strictly speaking threadsafe. If they are invoked at the | |
| 5615 ** same time as another thread is invoking sqlite3_backup_step() it is | |
| 5616 ** possible that they return invalid values. | |
| 5617 */ | |
| 5618 SQLITE_API sqlite3_backup *sqlite3_backup_init( | |
| 5619 sqlite3 *pDest, /* Destination database handle */ | |
| 5620 const char *zDestName, /* Destination database name */ | |
| 5621 sqlite3 *pSource, /* Source database handle */ | |
| 5622 const char *zSourceName /* Source database name */ | |
| 5623 ); | |
| 5624 SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage); | |
| 5625 SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p); | |
| 5626 SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p); | |
| 5627 SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p); | |
| 5628 | |
| 5629 /* | |
| 5630 ** CAPI3REF: Unlock Notification | |
| 5631 ** EXPERIMENTAL | |
| 5632 ** | |
| 5633 ** When running in shared-cache mode, a database operation may fail with | |
| 5634 ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or | |
| 5635 ** individual tables within the shared-cache cannot be obtained. See | |
| 5636 ** [SQLite Shared-Cache Mode] for a description of shared-cache locking. | |
| 5637 ** This API may be used to register a callback that SQLite will invoke | |
| 5638 ** when the connection currently holding the required lock relinquishes it. | |
| 5639 ** This API is only available if the library was compiled with the | |
| 5640 ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined. | |
| 5641 ** | |
| 5642 ** See Also: [Using the SQLite Unlock Notification Feature]. | |
| 5643 ** | |
| 5644 ** Shared-cache locks are released when a database connection concludes | |
| 5645 ** its current transaction, either by committing it or rolling it back. | |
| 5646 ** | |
| 5647 ** When a connection (known as the blocked connection) fails to obtain a | |
| 5648 ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the | |
| 5649 ** identity of the database connection (the blocking connection) that | |
| 5650 ** has locked the required resource is stored internally. After an | |
| 5651 ** application receives an SQLITE_LOCKED error, it may call the | |
| 5652 ** sqlite3_unlock_notify() method with the blocked connection handle as | |
| 5653 ** the first argument to register for a callback that will be invoked | |
| 5654 ** when the blocking connections current transaction is concluded. The | |
| 5655 ** callback is invoked from within the [sqlite3_step] or [sqlite3_close] | |
| 5656 ** call that concludes the blocking connections transaction. | |
| 5657 ** | |
| 5658 ** If sqlite3_unlock_notify() is called in a multi-threaded application, | |
| 5659 ** there is a chance that the blocking connection will have already | |
| 5660 ** concluded its transaction by the time sqlite3_unlock_notify() is invoked. | |
| 5661 ** If this happens, then the specified callback is invoked immediately, | |
| 5662 ** from within the call to sqlite3_unlock_notify(). | |
| 5663 ** | |
| 5664 ** If the blocked connection is attempting to obtain a write-lock on a | |
| 5665 ** shared-cache table, and more than one other connection currently holds | |
| 5666 ** a read-lock on the same table, then SQLite arbitrarily selects one of | |
| 5667 ** the other connections to use as the blocking connection. | |
| 5668 ** | |
| 5669 ** There may be at most one unlock-notify callback registered by a | |
| 5670 ** blocked connection. If sqlite3_unlock_notify() is called when the | |
| 5671 ** blocked connection already has a registered unlock-notify callback, | |
| 5672 ** then the new callback replaces the old. If sqlite3_unlock_notify() is | |
| 5673 ** called with a NULL pointer as its second argument, then any existing | |
| 5674 ** unlock-notify callback is cancelled. The blocked connections | |
| 5675 ** unlock-notify callback may also be canceled by closing the blocked | |
| 5676 ** connection using [sqlite3_close()]. | |
| 5677 ** | |
| 5678 ** The unlock-notify callback is not reentrant. If an application invokes | |
| 5679 ** any sqlite3_xxx API functions from within an unlock-notify callback, a | |
| 5680 ** crash or deadlock may be the result. | |
| 5681 ** | |
| 5682 ** Unless deadlock is detected (see below), sqlite3_unlock_notify() always | |
| 5683 ** returns SQLITE_OK. | |
| 5684 ** | |
| 5685 ** <b>Callback Invocation Details</b> | |
| 5686 ** | |
| 5687 ** When an unlock-notify callback is registered, the application provides a | |
| 5688 ** single void* pointer that is passed to the callback when it is invoked. | |
| 5689 ** However, the signature of the callback function allows SQLite to pass | |
| 5690 ** it an array of void* context pointers. The first argument passed to | |
| 5691 ** an unlock-notify callback is a pointer to an array of void* pointers, | |
| 5692 ** and the second is the number of entries in the array. | |
| 5693 ** | |
| 5694 ** When a blocking connections transaction is concluded, there may be | |
| 5695 ** more than one blocked connection that has registered for an unlock-notify | |
| 5696 ** callback. If two or more such blocked connections have specified the | |
| 5697 ** same callback function, then instead of invoking the callback function | |
| 5698 ** multiple times, it is invoked once with the set of void* context pointers | |
| 5699 ** specified by the blocked connections bundled together into an array. | |
| 5700 ** This gives the application an opportunity to prioritize any actions | |
| 5701 ** related to the set of unblocked database connections. | |
| 5702 ** | |
| 5703 ** <b>Deadlock Detection</b> | |
| 5704 ** | |
| 5705 ** Assuming that after registering for an unlock-notify callback a | |
| 5706 ** database waits for the callback to be issued before taking any further | |
| 5707 ** action (a reasonable assumption), then using this API may cause the | |
| 5708 ** application to deadlock. For example, if connection X is waiting for | |
| 5709 ** connection Y's transaction to be concluded, and similarly connection | |
| 5710 ** Y is waiting on connection X's transaction, then neither connection | |
| 5711 ** will proceed and the system may remain deadlocked indefinitely. | |
| 5712 ** | |
| 5713 ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock | |
| 5714 ** detection. If a given call to sqlite3_unlock_notify() would put the | |
| 5715 ** system in a deadlocked state, then SQLITE_LOCKED is returned and no | |
| 5716 ** unlock-notify callback is registered. The system is said to be in | |
| 5717 ** a deadlocked state if connection A has registered for an unlock-notify | |
| 5718 ** callback on the conclusion of connection B's transaction, and connection | |
| 5719 ** B has itself registered for an unlock-notify callback when connection | |
| 5720 ** A's transaction is concluded. Indirect deadlock is also detected, so | |
| 5721 ** the system is also considered to be deadlocked if connection B has | |
| 5722 ** registered for an unlock-notify callback on the conclusion of connection | |
| 5723 ** C's transaction, where connection C is waiting on connection A. Any | |
| 5724 ** number of levels of indirection are allowed. | |
| 5725 ** | |
| 5726 ** <b>The "DROP TABLE" Exception</b> | |
| 5727 ** | |
| 5728 ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost | |
| 5729 ** always appropriate to call sqlite3_unlock_notify(). There is however, | |
| 5730 ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement, | |
| 5731 ** SQLite checks if there are any currently executing SELECT statements | |
| 5732 ** that belong to the same connection. If there are, SQLITE_LOCKED is | |
| 5733 ** returned. In this case there is no "blocking connection", so invoking | |
| 5734 ** sqlite3_unlock_notify() results in the unlock-notify callback being | |
| 5735 ** invoked immediately. If the application then re-attempts the "DROP TABLE" | |
| 5736 ** or "DROP INDEX" query, an infinite loop might be the result. | |
| 5737 ** | |
| 5738 ** One way around this problem is to check the extended error code returned | |
| 5739 ** by an sqlite3_step() call. If there is a blocking connection, then the | |
| 5740 ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in | |
| 5741 ** the special "DROP TABLE/INDEX" case, the extended error code is just | |
| 5742 ** SQLITE_LOCKED. | |
| 5743 */ | |
| 5744 SQLITE_API int sqlite3_unlock_notify( | |
| 5745 sqlite3 *pBlocked, /* Waiting connection */ | |
| 5746 void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */ | |
| 5747 void *pNotifyArg /* Argument to pass to xNotify */ | |
| 5748 ); | |
| 5749 | |
| 5750 | |
| 5751 /* | |
| 5752 ** CAPI3REF: String Comparison | |
| 5753 ** EXPERIMENTAL | |
| 5754 ** | |
| 5755 ** The [sqlite3_strnicmp()] API allows applications and extensions to | |
| 5756 ** compare the contents of two buffers containing UTF-8 strings in a | |
| 5757 ** case-indendent fashion, using the same definition of case independence | |
| 5758 ** that SQLite uses internally when comparing identifiers. | |
| 5759 */ | |
| 5760 SQLITE_API int sqlite3_strnicmp(const char *, const char *, int); | |
| 5761 | |
| 5762 /* | |
| 5763 ** Undo the hack that converts floating point types to integer for | |
| 5764 ** builds on processors without floating point support. | |
| 5765 */ | |
| 5766 #ifdef SQLITE_OMIT_FLOATING_POINT | |
| 5767 # undef double | |
| 5768 #endif | |
| 5769 | |
| 5770 #ifdef __cplusplus | |
| 5771 } /* End of the 'extern "C"' block */ | |
| 5772 #endif | |
| 5773 #endif | |
| 5774 | |
| OLD | NEW |