Alexander Chemeris | 040b305 | 2013-06-16 14:29:54 +0400 | [diff] [blame] | 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 |
| 85 | ** |
| 86 | ** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header |
| 87 | ** evaluates to a string literal that is the SQLite version in the |
| 88 | ** format "X.Y.Z" where X is the major version number (always 3 for |
| 89 | ** SQLite3) and Y is the minor version number and Z is the release number.)^ |
| 90 | ** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer |
| 91 | ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same |
| 92 | ** numbers used in [SQLITE_VERSION].)^ |
| 93 | ** The SQLITE_VERSION_NUMBER for any given release of SQLite will also |
| 94 | ** be larger than the release from which it is derived. Either Y will |
| 95 | ** be held constant and Z will be incremented or else Y will be incremented |
| 96 | ** and Z will be reset to zero. |
| 97 | ** |
| 98 | ** Since version 3.6.18, SQLite source code has been stored in the |
| 99 | ** <a href="http://www.fossil-scm.org/">Fossil configuration management |
| 100 | ** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to |
| 101 | ** a string which identifies a particular check-in of SQLite |
| 102 | ** within its configuration management system. ^The SQLITE_SOURCE_ID |
| 103 | ** string contains the date and time of the check-in (UTC) and an SHA1 |
| 104 | ** hash of the entire source tree. |
| 105 | ** |
| 106 | ** See also: [sqlite3_libversion()], |
| 107 | ** [sqlite3_libversion_number()], [sqlite3_sourceid()], |
| 108 | ** [sqlite_version()] and [sqlite_source_id()]. |
| 109 | */ |
| 110 | #define SQLITE_VERSION "3.7.13" |
| 111 | #define SQLITE_VERSION_NUMBER 3007013 |
| 112 | #define SQLITE_SOURCE_ID "2012-06-11 02:05:22 f5b5a13f7394dc143aa136f1d4faba6839eaa6dc" |
| 113 | |
| 114 | /* |
| 115 | ** CAPI3REF: Run-Time Library Version Numbers |
| 116 | ** KEYWORDS: sqlite3_version, sqlite3_sourceid |
| 117 | ** |
| 118 | ** These interfaces provide the same information as the [SQLITE_VERSION], |
| 119 | ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros |
| 120 | ** but are associated with the library instead of the header file. ^(Cautious |
| 121 | ** programmers might include assert() statements in their application to |
| 122 | ** verify that values returned by these interfaces match the macros in |
| 123 | ** the header, and thus insure that the application is |
| 124 | ** compiled with matching library and header files. |
| 125 | ** |
| 126 | ** <blockquote><pre> |
| 127 | ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER ); |
| 128 | ** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 ); |
| 129 | ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 ); |
| 130 | ** </pre></blockquote>)^ |
| 131 | ** |
| 132 | ** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION] |
| 133 | ** macro. ^The sqlite3_libversion() function returns a pointer to the |
| 134 | ** to the sqlite3_version[] string constant. The sqlite3_libversion() |
| 135 | ** function is provided for use in DLLs since DLL users usually do not have |
| 136 | ** direct access to string constants within the DLL. ^The |
| 137 | ** sqlite3_libversion_number() function returns an integer equal to |
| 138 | ** [SQLITE_VERSION_NUMBER]. ^The sqlite3_sourceid() function returns |
| 139 | ** a pointer to a string constant whose value is the same as the |
| 140 | ** [SQLITE_SOURCE_ID] C preprocessor macro. |
| 141 | ** |
| 142 | ** See also: [sqlite_version()] and [sqlite_source_id()]. |
| 143 | */ |
| 144 | SQLITE_API SQLITE_EXTERN const char sqlite3_version[]; |
| 145 | SQLITE_API const char *sqlite3_libversion(void); |
| 146 | SQLITE_API const char *sqlite3_sourceid(void); |
| 147 | SQLITE_API int sqlite3_libversion_number(void); |
| 148 | |
| 149 | /* |
| 150 | ** CAPI3REF: Run-Time Library Compilation Options Diagnostics |
| 151 | ** |
| 152 | ** ^The sqlite3_compileoption_used() function returns 0 or 1 |
| 153 | ** indicating whether the specified option was defined at |
| 154 | ** compile time. ^The SQLITE_ prefix may be omitted from the |
| 155 | ** option name passed to sqlite3_compileoption_used(). |
| 156 | ** |
| 157 | ** ^The sqlite3_compileoption_get() function allows iterating |
| 158 | ** over the list of options that were defined at compile time by |
| 159 | ** returning the N-th compile time option string. ^If N is out of range, |
| 160 | ** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_ |
| 161 | ** prefix is omitted from any strings returned by |
| 162 | ** sqlite3_compileoption_get(). |
| 163 | ** |
| 164 | ** ^Support for the diagnostic functions sqlite3_compileoption_used() |
| 165 | ** and sqlite3_compileoption_get() may be omitted by specifying the |
| 166 | ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time. |
| 167 | ** |
| 168 | ** See also: SQL functions [sqlite_compileoption_used()] and |
| 169 | ** [sqlite_compileoption_get()] and the [compile_options pragma]. |
| 170 | */ |
| 171 | #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS |
| 172 | SQLITE_API int sqlite3_compileoption_used(const char *zOptName); |
| 173 | SQLITE_API const char *sqlite3_compileoption_get(int N); |
| 174 | #endif |
| 175 | |
| 176 | /* |
| 177 | ** CAPI3REF: Test To See If The Library Is Threadsafe |
| 178 | ** |
| 179 | ** ^The sqlite3_threadsafe() function returns zero if and only if |
| 180 | ** SQLite was compiled with mutexing code omitted due to the |
| 181 | ** [SQLITE_THREADSAFE] compile-time option being set to 0. |
| 182 | ** |
| 183 | ** SQLite can be compiled with or without mutexes. When |
| 184 | ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes |
| 185 | ** are enabled and SQLite is threadsafe. When the |
| 186 | ** [SQLITE_THREADSAFE] macro is 0, |
| 187 | ** the mutexes are omitted. Without the mutexes, it is not safe |
| 188 | ** to use SQLite concurrently from more than one thread. |
| 189 | ** |
| 190 | ** Enabling mutexes incurs a measurable performance penalty. |
| 191 | ** So if speed is of utmost importance, it makes sense to disable |
| 192 | ** the mutexes. But for maximum safety, mutexes should be enabled. |
| 193 | ** ^The default behavior is for mutexes to be enabled. |
| 194 | ** |
| 195 | ** This interface can be used by an application to make sure that the |
| 196 | ** version of SQLite that it is linking against was compiled with |
| 197 | ** the desired setting of the [SQLITE_THREADSAFE] macro. |
| 198 | ** |
| 199 | ** This interface only reports on the compile-time mutex setting |
| 200 | ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with |
| 201 | ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but |
| 202 | ** can be fully or partially disabled using a call to [sqlite3_config()] |
| 203 | ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD], |
| 204 | ** or [SQLITE_CONFIG_MUTEX]. ^(The return value of the |
| 205 | ** sqlite3_threadsafe() function shows only the compile-time setting of |
| 206 | ** thread safety, not any run-time changes to that setting made by |
| 207 | ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe() |
| 208 | ** is unchanged by calls to sqlite3_config().)^ |
| 209 | ** |
| 210 | ** See the [threading mode] documentation for additional information. |
| 211 | */ |
| 212 | SQLITE_API int sqlite3_threadsafe(void); |
| 213 | |
| 214 | /* |
| 215 | ** CAPI3REF: Database Connection Handle |
| 216 | ** KEYWORDS: {database connection} {database connections} |
| 217 | ** |
| 218 | ** Each open SQLite database is represented by a pointer to an instance of |
| 219 | ** the opaque structure named "sqlite3". It is useful to think of an sqlite3 |
| 220 | ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and |
| 221 | ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()] |
| 222 | ** is its destructor. There are many other interfaces (such as |
| 223 | ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and |
| 224 | ** [sqlite3_busy_timeout()] to name but three) that are methods on an |
| 225 | ** sqlite3 object. |
| 226 | */ |
| 227 | typedef struct sqlite3 sqlite3; |
| 228 | |
| 229 | /* |
| 230 | ** CAPI3REF: 64-Bit Integer Types |
| 231 | ** KEYWORDS: sqlite_int64 sqlite_uint64 |
| 232 | ** |
| 233 | ** Because there is no cross-platform way to specify 64-bit integer types |
| 234 | ** SQLite includes typedefs for 64-bit signed and unsigned integers. |
| 235 | ** |
| 236 | ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions. |
| 237 | ** The sqlite_int64 and sqlite_uint64 types are supported for backwards |
| 238 | ** compatibility only. |
| 239 | ** |
| 240 | ** ^The sqlite3_int64 and sqlite_int64 types can store integer values |
| 241 | ** between -9223372036854775808 and +9223372036854775807 inclusive. ^The |
| 242 | ** sqlite3_uint64 and sqlite_uint64 types can store integer values |
| 243 | ** between 0 and +18446744073709551615 inclusive. |
| 244 | */ |
| 245 | #ifdef SQLITE_INT64_TYPE |
| 246 | typedef SQLITE_INT64_TYPE sqlite_int64; |
| 247 | typedef unsigned SQLITE_INT64_TYPE sqlite_uint64; |
| 248 | #elif defined(_MSC_VER) || defined(__BORLANDC__) |
| 249 | typedef __int64 sqlite_int64; |
| 250 | typedef unsigned __int64 sqlite_uint64; |
| 251 | #else |
| 252 | typedef long long int sqlite_int64; |
| 253 | typedef unsigned long long int sqlite_uint64; |
| 254 | #endif |
| 255 | typedef sqlite_int64 sqlite3_int64; |
| 256 | typedef sqlite_uint64 sqlite3_uint64; |
| 257 | |
| 258 | /* |
| 259 | ** If compiling for a processor that lacks floating point support, |
| 260 | ** substitute integer for floating-point. |
| 261 | */ |
| 262 | #ifdef SQLITE_OMIT_FLOATING_POINT |
| 263 | # define double sqlite3_int64 |
| 264 | #endif |
| 265 | |
| 266 | /* |
| 267 | ** CAPI3REF: Closing A Database Connection |
| 268 | ** |
| 269 | ** ^The sqlite3_close() routine is the destructor for the [sqlite3] object. |
| 270 | ** ^Calls to sqlite3_close() return SQLITE_OK if the [sqlite3] object is |
| 271 | ** successfully destroyed and all associated resources are deallocated. |
| 272 | ** |
| 273 | ** Applications must [sqlite3_finalize | finalize] all [prepared statements] |
| 274 | ** and [sqlite3_blob_close | close] all [BLOB handles] associated with |
| 275 | ** the [sqlite3] object prior to attempting to close the object. ^If |
| 276 | ** sqlite3_close() is called on a [database connection] that still has |
| 277 | ** outstanding [prepared statements] or [BLOB handles], then it returns |
| 278 | ** SQLITE_BUSY. |
| 279 | ** |
| 280 | ** ^If [sqlite3_close()] is invoked while a transaction is open, |
| 281 | ** the transaction is automatically rolled back. |
| 282 | ** |
| 283 | ** The C parameter to [sqlite3_close(C)] must be either a NULL |
| 284 | ** pointer or an [sqlite3] object pointer obtained |
| 285 | ** from [sqlite3_open()], [sqlite3_open16()], or |
| 286 | ** [sqlite3_open_v2()], and not previously closed. |
| 287 | ** ^Calling sqlite3_close() with a NULL pointer argument is a |
| 288 | ** harmless no-op. |
| 289 | */ |
| 290 | SQLITE_API int sqlite3_close(sqlite3 *); |
| 291 | |
| 292 | /* |
| 293 | ** The type for a callback function. |
| 294 | ** This is legacy and deprecated. It is included for historical |
| 295 | ** compatibility and is not documented. |
| 296 | */ |
| 297 | typedef int (*sqlite3_callback)(void*,int,char**, char**); |
| 298 | |
| 299 | /* |
| 300 | ** CAPI3REF: One-Step Query Execution Interface |
| 301 | ** |
| 302 | ** The sqlite3_exec() interface is a convenience wrapper around |
| 303 | ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()], |
| 304 | ** that allows an application to run multiple statements of SQL |
| 305 | ** without having to use a lot of C code. |
| 306 | ** |
| 307 | ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded, |
| 308 | ** semicolon-separate SQL statements passed into its 2nd argument, |
| 309 | ** in the context of the [database connection] passed in as its 1st |
| 310 | ** argument. ^If the callback function of the 3rd argument to |
| 311 | ** sqlite3_exec() is not NULL, then it is invoked for each result row |
| 312 | ** coming out of the evaluated SQL statements. ^The 4th argument to |
| 313 | ** sqlite3_exec() is relayed through to the 1st argument of each |
| 314 | ** callback invocation. ^If the callback pointer to sqlite3_exec() |
| 315 | ** is NULL, then no callback is ever invoked and result rows are |
| 316 | ** ignored. |
| 317 | ** |
| 318 | ** ^If an error occurs while evaluating the SQL statements passed into |
| 319 | ** sqlite3_exec(), then execution of the current statement stops and |
| 320 | ** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec() |
| 321 | ** is not NULL then any error message is written into memory obtained |
| 322 | ** from [sqlite3_malloc()] and passed back through the 5th parameter. |
| 323 | ** To avoid memory leaks, the application should invoke [sqlite3_free()] |
| 324 | ** on error message strings returned through the 5th parameter of |
| 325 | ** of sqlite3_exec() after the error message string is no longer needed. |
| 326 | ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors |
| 327 | ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to |
| 328 | ** NULL before returning. |
| 329 | ** |
| 330 | ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec() |
| 331 | ** routine returns SQLITE_ABORT without invoking the callback again and |
| 332 | ** without running any subsequent SQL statements. |
| 333 | ** |
| 334 | ** ^The 2nd argument to the sqlite3_exec() callback function is the |
| 335 | ** number of columns in the result. ^The 3rd argument to the sqlite3_exec() |
| 336 | ** callback is an array of pointers to strings obtained as if from |
| 337 | ** [sqlite3_column_text()], one for each column. ^If an element of a |
| 338 | ** result row is NULL then the corresponding string pointer for the |
| 339 | ** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the |
| 340 | ** sqlite3_exec() callback is an array of pointers to strings where each |
| 341 | ** entry represents the name of corresponding result column as obtained |
| 342 | ** from [sqlite3_column_name()]. |
| 343 | ** |
| 344 | ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer |
| 345 | ** to an empty string, or a pointer that contains only whitespace and/or |
| 346 | ** SQL comments, then no SQL statements are evaluated and the database |
| 347 | ** is not changed. |
| 348 | ** |
| 349 | ** Restrictions: |
| 350 | ** |
| 351 | ** <ul> |
| 352 | ** <li> The application must insure that the 1st parameter to sqlite3_exec() |
| 353 | ** is a valid and open [database connection]. |
| 354 | ** <li> The application must not close [database connection] specified by |
| 355 | ** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running. |
| 356 | ** <li> The application must not modify the SQL statement text passed into |
| 357 | ** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running. |
| 358 | ** </ul> |
| 359 | */ |
| 360 | SQLITE_API int sqlite3_exec( |
| 361 | sqlite3*, /* An open database */ |
| 362 | const char *sql, /* SQL to be evaluated */ |
| 363 | int (*callback)(void*,int,char**,char**), /* Callback function */ |
| 364 | void *, /* 1st argument to callback */ |
| 365 | char **errmsg /* Error msg written here */ |
| 366 | ); |
| 367 | |
| 368 | /* |
| 369 | ** CAPI3REF: Result Codes |
| 370 | ** KEYWORDS: SQLITE_OK {error code} {error codes} |
| 371 | ** KEYWORDS: {result code} {result codes} |
| 372 | ** |
| 373 | ** Many SQLite functions return an integer result code from the set shown |
| 374 | ** here in order to indicate success or failure. |
| 375 | ** |
| 376 | ** New error codes may be added in future versions of SQLite. |
| 377 | ** |
| 378 | ** See also: [SQLITE_IOERR_READ | extended result codes], |
| 379 | ** [sqlite3_vtab_on_conflict()] [SQLITE_ROLLBACK | result codes]. |
| 380 | */ |
| 381 | #define SQLITE_OK 0 /* Successful result */ |
| 382 | /* beginning-of-error-codes */ |
| 383 | #define SQLITE_ERROR 1 /* SQL error or missing database */ |
| 384 | #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */ |
| 385 | #define SQLITE_PERM 3 /* Access permission denied */ |
| 386 | #define SQLITE_ABORT 4 /* Callback routine requested an abort */ |
| 387 | #define SQLITE_BUSY 5 /* The database file is locked */ |
| 388 | #define SQLITE_LOCKED 6 /* A table in the database is locked */ |
| 389 | #define SQLITE_NOMEM 7 /* A malloc() failed */ |
| 390 | #define SQLITE_READONLY 8 /* Attempt to write a readonly database */ |
| 391 | #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/ |
| 392 | #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ |
| 393 | #define SQLITE_CORRUPT 11 /* The database disk image is malformed */ |
| 394 | #define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */ |
| 395 | #define SQLITE_FULL 13 /* Insertion failed because database is full */ |
| 396 | #define SQLITE_CANTOPEN 14 /* Unable to open the database file */ |
| 397 | #define SQLITE_PROTOCOL 15 /* Database lock protocol error */ |
| 398 | #define SQLITE_EMPTY 16 /* Database is empty */ |
| 399 | #define SQLITE_SCHEMA 17 /* The database schema changed */ |
| 400 | #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */ |
| 401 | #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */ |
| 402 | #define SQLITE_MISMATCH 20 /* Data type mismatch */ |
| 403 | #define SQLITE_MISUSE 21 /* Library used incorrectly */ |
| 404 | #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ |
| 405 | #define SQLITE_AUTH 23 /* Authorization denied */ |
| 406 | #define SQLITE_FORMAT 24 /* Auxiliary database format error */ |
| 407 | #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */ |
| 408 | #define SQLITE_NOTADB 26 /* File opened that is not a database file */ |
| 409 | #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */ |
| 410 | #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */ |
| 411 | /* end-of-error-codes */ |
| 412 | |
| 413 | /* |
| 414 | ** CAPI3REF: Extended Result Codes |
| 415 | ** KEYWORDS: {extended error code} {extended error codes} |
| 416 | ** KEYWORDS: {extended result code} {extended result codes} |
| 417 | ** |
| 418 | ** In its default configuration, SQLite API routines return one of 26 integer |
| 419 | ** [SQLITE_OK | result codes]. However, experience has shown that many of |
| 420 | ** these result codes are too coarse-grained. They do not provide as |
| 421 | ** much information about problems as programmers might like. In an effort to |
| 422 | ** address this, newer versions of SQLite (version 3.3.8 and later) include |
| 423 | ** support for additional result codes that provide more detailed information |
| 424 | ** about errors. The extended result codes are enabled or disabled |
| 425 | ** on a per database connection basis using the |
| 426 | ** [sqlite3_extended_result_codes()] API. |
| 427 | ** |
| 428 | ** Some of the available extended result codes are listed here. |
| 429 | ** One may expect the number of extended result codes will be expand |
| 430 | ** over time. Software that uses extended result codes should expect |
| 431 | ** to see new result codes in future releases of SQLite. |
| 432 | ** |
| 433 | ** The SQLITE_OK result code will never be extended. It will always |
| 434 | ** be exactly zero. |
| 435 | */ |
| 436 | #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) |
| 437 | #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) |
| 438 | #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) |
| 439 | #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) |
| 440 | #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) |
| 441 | #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) |
| 442 | #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) |
| 443 | #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) |
| 444 | #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) |
| 445 | #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) |
| 446 | #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) |
| 447 | #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) |
| 448 | #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8)) |
| 449 | #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8)) |
| 450 | #define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8)) |
| 451 | #define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8)) |
| 452 | #define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8)) |
| 453 | #define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8)) |
| 454 | #define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8)) |
| 455 | #define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8)) |
| 456 | #define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8)) |
| 457 | #define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8)) |
| 458 | #define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8)) |
| 459 | #define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8)) |
| 460 | #define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8)) |
| 461 | #define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8)) |
| 462 | #define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8)) |
| 463 | #define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8)) |
| 464 | #define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8)) |
| 465 | #define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8)) |
| 466 | |
| 467 | /* |
| 468 | ** CAPI3REF: Flags For File Open Operations |
| 469 | ** |
| 470 | ** These bit values are intended for use in the |
| 471 | ** 3rd parameter to the [sqlite3_open_v2()] interface and |
| 472 | ** in the 4th parameter to the [sqlite3_vfs.xOpen] method. |
| 473 | */ |
| 474 | #define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */ |
| 475 | #define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */ |
| 476 | #define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */ |
| 477 | #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */ |
| 478 | #define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */ |
| 479 | #define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */ |
| 480 | #define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */ |
| 481 | #define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */ |
| 482 | #define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */ |
| 483 | #define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */ |
| 484 | #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */ |
| 485 | #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */ |
| 486 | #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */ |
| 487 | #define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */ |
| 488 | #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */ |
| 489 | #define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */ |
| 490 | #define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */ |
| 491 | #define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */ |
| 492 | #define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */ |
| 493 | #define SQLITE_OPEN_WAL 0x00080000 /* VFS only */ |
| 494 | |
| 495 | /* Reserved: 0x00F00000 */ |
| 496 | |
| 497 | /* |
| 498 | ** CAPI3REF: Device Characteristics |
| 499 | ** |
| 500 | ** The xDeviceCharacteristics method of the [sqlite3_io_methods] |
| 501 | ** object returns an integer which is a vector of the these |
| 502 | ** bit values expressing I/O characteristics of the mass storage |
| 503 | ** device that holds the file that the [sqlite3_io_methods] |
| 504 | ** refers to. |
| 505 | ** |
| 506 | ** The SQLITE_IOCAP_ATOMIC property means that all writes of |
| 507 | ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values |
| 508 | ** mean that writes of blocks that are nnn bytes in size and |
| 509 | ** are aligned to an address which is an integer multiple of |
| 510 | ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means |
| 511 | ** that when data is appended to a file, the data is appended |
| 512 | ** first then the size of the file is extended, never the other |
| 513 | ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that |
| 514 | ** information is written to disk in the same order as calls |
| 515 | ** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that |
| 516 | ** after reboot following a crash or power loss, the only bytes in a |
| 517 | ** file that were written at the application level might have changed |
| 518 | ** and that adjacent bytes, even bytes within the same sector are |
| 519 | ** guaranteed to be unchanged. |
| 520 | */ |
| 521 | #define SQLITE_IOCAP_ATOMIC 0x00000001 |
| 522 | #define SQLITE_IOCAP_ATOMIC512 0x00000002 |
| 523 | #define SQLITE_IOCAP_ATOMIC1K 0x00000004 |
| 524 | #define SQLITE_IOCAP_ATOMIC2K 0x00000008 |
| 525 | #define SQLITE_IOCAP_ATOMIC4K 0x00000010 |
| 526 | #define SQLITE_IOCAP_ATOMIC8K 0x00000020 |
| 527 | #define SQLITE_IOCAP_ATOMIC16K 0x00000040 |
| 528 | #define SQLITE_IOCAP_ATOMIC32K 0x00000080 |
| 529 | #define SQLITE_IOCAP_ATOMIC64K 0x00000100 |
| 530 | #define SQLITE_IOCAP_SAFE_APPEND 0x00000200 |
| 531 | #define SQLITE_IOCAP_SEQUENTIAL 0x00000400 |
| 532 | #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800 |
| 533 | #define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000 |
| 534 | |
| 535 | /* |
| 536 | ** CAPI3REF: File Locking Levels |
| 537 | ** |
| 538 | ** SQLite uses one of these integer values as the second |
| 539 | ** argument to calls it makes to the xLock() and xUnlock() methods |
| 540 | ** of an [sqlite3_io_methods] object. |
| 541 | */ |
| 542 | #define SQLITE_LOCK_NONE 0 |
| 543 | #define SQLITE_LOCK_SHARED 1 |
| 544 | #define SQLITE_LOCK_RESERVED 2 |
| 545 | #define SQLITE_LOCK_PENDING 3 |
| 546 | #define SQLITE_LOCK_EXCLUSIVE 4 |
| 547 | |
| 548 | /* |
| 549 | ** CAPI3REF: Synchronization Type Flags |
| 550 | ** |
| 551 | ** When SQLite invokes the xSync() method of an |
| 552 | ** [sqlite3_io_methods] object it uses a combination of |
| 553 | ** these integer values as the second argument. |
| 554 | ** |
| 555 | ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the |
| 556 | ** sync operation only needs to flush data to mass storage. Inode |
| 557 | ** information need not be flushed. If the lower four bits of the flag |
| 558 | ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics. |
| 559 | ** If the lower four bits equal SQLITE_SYNC_FULL, that means |
| 560 | ** to use Mac OS X style fullsync instead of fsync(). |
| 561 | ** |
| 562 | ** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags |
| 563 | ** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL |
| 564 | ** settings. The [synchronous pragma] determines when calls to the |
| 565 | ** xSync VFS method occur and applies uniformly across all platforms. |
| 566 | ** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how |
| 567 | ** energetic or rigorous or forceful the sync operations are and |
| 568 | ** only make a difference on Mac OSX for the default SQLite code. |
| 569 | ** (Third-party VFS implementations might also make the distinction |
| 570 | ** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the |
| 571 | ** operating systems natively supported by SQLite, only Mac OSX |
| 572 | ** cares about the difference.) |
| 573 | */ |
| 574 | #define SQLITE_SYNC_NORMAL 0x00002 |
| 575 | #define SQLITE_SYNC_FULL 0x00003 |
| 576 | #define SQLITE_SYNC_DATAONLY 0x00010 |
| 577 | |
| 578 | /* |
| 579 | ** CAPI3REF: OS Interface Open File Handle |
| 580 | ** |
| 581 | ** An [sqlite3_file] object represents an open file in the |
| 582 | ** [sqlite3_vfs | OS interface layer]. Individual OS interface |
| 583 | ** implementations will |
| 584 | ** want to subclass this object by appending additional fields |
| 585 | ** for their own use. The pMethods entry is a pointer to an |
| 586 | ** [sqlite3_io_methods] object that defines methods for performing |
| 587 | ** I/O operations on the open file. |
| 588 | */ |
| 589 | typedef struct sqlite3_file sqlite3_file; |
| 590 | struct sqlite3_file { |
| 591 | const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ |
| 592 | }; |
| 593 | |
| 594 | /* |
| 595 | ** CAPI3REF: OS Interface File Virtual Methods Object |
| 596 | ** |
| 597 | ** Every file opened by the [sqlite3_vfs.xOpen] method populates an |
| 598 | ** [sqlite3_file] object (or, more commonly, a subclass of the |
| 599 | ** [sqlite3_file] object) with a pointer to an instance of this object. |
| 600 | ** This object defines the methods used to perform various operations |
| 601 | ** against the open file represented by the [sqlite3_file] object. |
| 602 | ** |
| 603 | ** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element |
| 604 | ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method |
| 605 | ** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The |
| 606 | ** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen] |
| 607 | ** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element |
| 608 | ** to NULL. |
| 609 | ** |
| 610 | ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or |
| 611 | ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). |
| 612 | ** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY] |
| 613 | ** flag may be ORed in to indicate that only the data of the file |
| 614 | ** and not its inode needs to be synced. |
| 615 | ** |
| 616 | ** The integer values to xLock() and xUnlock() are one of |
| 617 | ** <ul> |
| 618 | ** <li> [SQLITE_LOCK_NONE], |
| 619 | ** <li> [SQLITE_LOCK_SHARED], |
| 620 | ** <li> [SQLITE_LOCK_RESERVED], |
| 621 | ** <li> [SQLITE_LOCK_PENDING], or |
| 622 | ** <li> [SQLITE_LOCK_EXCLUSIVE]. |
| 623 | ** </ul> |
| 624 | ** xLock() increases the lock. xUnlock() decreases the lock. |
| 625 | ** The xCheckReservedLock() method checks whether any database connection, |
| 626 | ** either in this process or in some other process, is holding a RESERVED, |
| 627 | ** PENDING, or EXCLUSIVE lock on the file. It returns true |
| 628 | ** if such a lock exists and false otherwise. |
| 629 | ** |
| 630 | ** The xFileControl() method is a generic interface that allows custom |
| 631 | ** VFS implementations to directly control an open file using the |
| 632 | ** [sqlite3_file_control()] interface. The second "op" argument is an |
| 633 | ** integer opcode. The third argument is a generic pointer intended to |
| 634 | ** point to a structure that may contain arguments or space in which to |
| 635 | ** write return values. Potential uses for xFileControl() might be |
| 636 | ** functions to enable blocking locks with timeouts, to change the |
| 637 | ** locking strategy (for example to use dot-file locks), to inquire |
| 638 | ** about the status of a lock, or to break stale locks. The SQLite |
| 639 | ** core reserves all opcodes less than 100 for its own use. |
| 640 | ** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available. |
| 641 | ** Applications that define a custom xFileControl method should use opcodes |
| 642 | ** greater than 100 to avoid conflicts. VFS implementations should |
| 643 | ** return [SQLITE_NOTFOUND] for file control opcodes that they do not |
| 644 | ** recognize. |
| 645 | ** |
| 646 | ** The xSectorSize() method returns the sector size of the |
| 647 | ** device that underlies the file. The sector size is the |
| 648 | ** minimum write that can be performed without disturbing |
| 649 | ** other bytes in the file. The xDeviceCharacteristics() |
| 650 | ** method returns a bit vector describing behaviors of the |
| 651 | ** underlying device: |
| 652 | ** |
| 653 | ** <ul> |
| 654 | ** <li> [SQLITE_IOCAP_ATOMIC] |
| 655 | ** <li> [SQLITE_IOCAP_ATOMIC512] |
| 656 | ** <li> [SQLITE_IOCAP_ATOMIC1K] |
| 657 | ** <li> [SQLITE_IOCAP_ATOMIC2K] |
| 658 | ** <li> [SQLITE_IOCAP_ATOMIC4K] |
| 659 | ** <li> [SQLITE_IOCAP_ATOMIC8K] |
| 660 | ** <li> [SQLITE_IOCAP_ATOMIC16K] |
| 661 | ** <li> [SQLITE_IOCAP_ATOMIC32K] |
| 662 | ** <li> [SQLITE_IOCAP_ATOMIC64K] |
| 663 | ** <li> [SQLITE_IOCAP_SAFE_APPEND] |
| 664 | ** <li> [SQLITE_IOCAP_SEQUENTIAL] |
| 665 | ** </ul> |
| 666 | ** |
| 667 | ** The SQLITE_IOCAP_ATOMIC property means that all writes of |
| 668 | ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values |
| 669 | ** mean that writes of blocks that are nnn bytes in size and |
| 670 | ** are aligned to an address which is an integer multiple of |
| 671 | ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means |
| 672 | ** that when data is appended to a file, the data is appended |
| 673 | ** first then the size of the file is extended, never the other |
| 674 | ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that |
| 675 | ** information is written to disk in the same order as calls |
| 676 | ** to xWrite(). |
| 677 | ** |
| 678 | ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill |
| 679 | ** in the unread portions of the buffer with zeros. A VFS that |
| 680 | ** fails to zero-fill short reads might seem to work. However, |
| 681 | ** failure to zero-fill short reads will eventually lead to |
| 682 | ** database corruption. |
| 683 | */ |
| 684 | typedef struct sqlite3_io_methods sqlite3_io_methods; |
| 685 | struct sqlite3_io_methods { |
| 686 | int iVersion; |
| 687 | int (*xClose)(sqlite3_file*); |
| 688 | int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); |
| 689 | int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); |
| 690 | int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); |
| 691 | int (*xSync)(sqlite3_file*, int flags); |
| 692 | int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); |
| 693 | int (*xLock)(sqlite3_file*, int); |
| 694 | int (*xUnlock)(sqlite3_file*, int); |
| 695 | int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); |
| 696 | int (*xFileControl)(sqlite3_file*, int op, void *pArg); |
| 697 | int (*xSectorSize)(sqlite3_file*); |
| 698 | int (*xDeviceCharacteristics)(sqlite3_file*); |
| 699 | /* Methods above are valid for version 1 */ |
| 700 | int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**); |
| 701 | int (*xShmLock)(sqlite3_file*, int offset, int n, int flags); |
| 702 | void (*xShmBarrier)(sqlite3_file*); |
| 703 | int (*xShmUnmap)(sqlite3_file*, int deleteFlag); |
| 704 | /* Methods above are valid for version 2 */ |
| 705 | /* Additional methods may be added in future releases */ |
| 706 | }; |
| 707 | |
| 708 | /* |
| 709 | ** CAPI3REF: Standard File Control Opcodes |
| 710 | ** |
| 711 | ** These integer constants are opcodes for the xFileControl method |
| 712 | ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] |
| 713 | ** interface. |
| 714 | ** |
| 715 | ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This |
| 716 | ** opcode causes the xFileControl method to write the current state of |
| 717 | ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED], |
| 718 | ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE]) |
| 719 | ** into an integer that the pArg argument points to. This capability |
| 720 | ** is used during testing and only needs to be supported when SQLITE_TEST |
| 721 | ** is defined. |
| 722 | ** <ul> |
| 723 | ** <li>[[SQLITE_FCNTL_SIZE_HINT]] |
| 724 | ** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS |
| 725 | ** layer a hint of how large the database file will grow to be during the |
| 726 | ** current transaction. This hint is not guaranteed to be accurate but it |
| 727 | ** is often close. The underlying VFS might choose to preallocate database |
| 728 | ** file space based on this hint in order to help writes to the database |
| 729 | ** file run faster. |
| 730 | ** |
| 731 | ** <li>[[SQLITE_FCNTL_CHUNK_SIZE]] |
| 732 | ** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS |
| 733 | ** extends and truncates the database file in chunks of a size specified |
| 734 | ** by the user. The fourth argument to [sqlite3_file_control()] should |
| 735 | ** point to an integer (type int) containing the new chunk-size to use |
| 736 | ** for the nominated database. Allocating database file space in large |
| 737 | ** chunks (say 1MB at a time), may reduce file-system fragmentation and |
| 738 | ** improve performance on some systems. |
| 739 | ** |
| 740 | ** <li>[[SQLITE_FCNTL_FILE_POINTER]] |
| 741 | ** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer |
| 742 | ** to the [sqlite3_file] object associated with a particular database |
| 743 | ** connection. See the [sqlite3_file_control()] documentation for |
| 744 | ** additional information. |
| 745 | ** |
| 746 | ** <li>[[SQLITE_FCNTL_SYNC_OMITTED]] |
| 747 | ** ^(The [SQLITE_FCNTL_SYNC_OMITTED] opcode is generated internally by |
| 748 | ** SQLite and sent to all VFSes in place of a call to the xSync method |
| 749 | ** when the database connection has [PRAGMA synchronous] set to OFF.)^ |
| 750 | ** Some specialized VFSes need this signal in order to operate correctly |
| 751 | ** when [PRAGMA synchronous | PRAGMA synchronous=OFF] is set, but most |
| 752 | ** VFSes do not need this signal and should silently ignore this opcode. |
| 753 | ** Applications should not call [sqlite3_file_control()] with this |
| 754 | ** opcode as doing so may disrupt the operation of the specialized VFSes |
| 755 | ** that do require it. |
| 756 | ** |
| 757 | ** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]] |
| 758 | ** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic |
| 759 | ** retry counts and intervals for certain disk I/O operations for the |
| 760 | ** windows [VFS] in order to provide robustness in the presence of |
| 761 | ** anti-virus programs. By default, the windows VFS will retry file read, |
| 762 | ** file write, and file delete operations up to 10 times, with a delay |
| 763 | ** of 25 milliseconds before the first retry and with the delay increasing |
| 764 | ** by an additional 25 milliseconds with each subsequent retry. This |
| 765 | ** opcode allows these two values (10 retries and 25 milliseconds of delay) |
| 766 | ** to be adjusted. The values are changed for all database connections |
| 767 | ** within the same process. The argument is a pointer to an array of two |
| 768 | ** integers where the first integer i the new retry count and the second |
| 769 | ** integer is the delay. If either integer is negative, then the setting |
| 770 | ** is not changed but instead the prior value of that setting is written |
| 771 | ** into the array entry, allowing the current retry settings to be |
| 772 | ** interrogated. The zDbName parameter is ignored. |
| 773 | ** |
| 774 | ** <li>[[SQLITE_FCNTL_PERSIST_WAL]] |
| 775 | ** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the |
| 776 | ** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary |
| 777 | ** write ahead log and shared memory files used for transaction control |
| 778 | ** are automatically deleted when the latest connection to the database |
| 779 | ** closes. Setting persistent WAL mode causes those files to persist after |
| 780 | ** close. Persisting the files is useful when other processes that do not |
| 781 | ** have write permission on the directory containing the database file want |
| 782 | ** to read the database file, as the WAL and shared memory files must exist |
| 783 | ** in order for the database to be readable. The fourth parameter to |
| 784 | ** [sqlite3_file_control()] for this opcode should be a pointer to an integer. |
| 785 | ** That integer is 0 to disable persistent WAL mode or 1 to enable persistent |
| 786 | ** WAL mode. If the integer is -1, then it is overwritten with the current |
| 787 | ** WAL persistence setting. |
| 788 | ** |
| 789 | ** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]] |
| 790 | ** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the |
| 791 | ** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting |
| 792 | ** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the |
| 793 | ** xDeviceCharacteristics methods. The fourth parameter to |
| 794 | ** [sqlite3_file_control()] for this opcode should be a pointer to an integer. |
| 795 | ** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage |
| 796 | ** mode. If the integer is -1, then it is overwritten with the current |
| 797 | ** zero-damage mode setting. |
| 798 | ** |
| 799 | ** <li>[[SQLITE_FCNTL_OVERWRITE]] |
| 800 | ** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening |
| 801 | ** a write transaction to indicate that, unless it is rolled back for some |
| 802 | ** reason, the entire database file will be overwritten by the current |
| 803 | ** transaction. This is used by VACUUM operations. |
| 804 | ** |
| 805 | ** <li>[[SQLITE_FCNTL_VFSNAME]] |
| 806 | ** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of |
| 807 | ** all [VFSes] in the VFS stack. The names are of all VFS shims and the |
| 808 | ** final bottom-level VFS are written into memory obtained from |
| 809 | ** [sqlite3_malloc()] and the result is stored in the char* variable |
| 810 | ** that the fourth parameter of [sqlite3_file_control()] points to. |
| 811 | ** The caller is responsible for freeing the memory when done. As with |
| 812 | ** all file-control actions, there is no guarantee that this will actually |
| 813 | ** do anything. Callers should initialize the char* variable to a NULL |
| 814 | ** pointer in case this file-control is not implemented. This file-control |
| 815 | ** is intended for diagnostic use only. |
| 816 | ** |
| 817 | ** <li>[[SQLITE_FCNTL_PRAGMA]] |
| 818 | ** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] |
| 819 | ** file control is sent to the open [sqlite3_file] object corresponding |
| 820 | ** to the database file to which the pragma statement refers. ^The argument |
| 821 | ** to the [SQLITE_FCNTL_PRAGMA] file control is an array of |
| 822 | ** pointers to strings (char**) in which the second element of the array |
| 823 | ** is the name of the pragma and the third element is the argument to the |
| 824 | ** pragma or NULL if the pragma has no argument. ^The handler for an |
| 825 | ** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element |
| 826 | ** of the char** argument point to a string obtained from [sqlite3_mprintf()] |
| 827 | ** or the equivalent and that string will become the result of the pragma or |
| 828 | ** the error message if the pragma fails. ^If the |
| 829 | ** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal |
| 830 | ** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA] |
| 831 | ** file control returns [SQLITE_OK], then the parser assumes that the |
| 832 | ** VFS has handled the PRAGMA itself and the parser generates a no-op |
| 833 | ** prepared statement. ^If the [SQLITE_FCNTL_PRAGMA] file control returns |
| 834 | ** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means |
| 835 | ** that the VFS encountered an error while handling the [PRAGMA] and the |
| 836 | ** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA] |
| 837 | ** file control occurs at the beginning of pragma statement analysis and so |
| 838 | ** it is able to override built-in [PRAGMA] statements. |
| 839 | ** </ul> |
| 840 | */ |
| 841 | #define SQLITE_FCNTL_LOCKSTATE 1 |
| 842 | #define SQLITE_GET_LOCKPROXYFILE 2 |
| 843 | #define SQLITE_SET_LOCKPROXYFILE 3 |
| 844 | #define SQLITE_LAST_ERRNO 4 |
| 845 | #define SQLITE_FCNTL_SIZE_HINT 5 |
| 846 | #define SQLITE_FCNTL_CHUNK_SIZE 6 |
| 847 | #define SQLITE_FCNTL_FILE_POINTER 7 |
| 848 | #define SQLITE_FCNTL_SYNC_OMITTED 8 |
| 849 | #define SQLITE_FCNTL_WIN32_AV_RETRY 9 |
| 850 | #define SQLITE_FCNTL_PERSIST_WAL 10 |
| 851 | #define SQLITE_FCNTL_OVERWRITE 11 |
| 852 | #define SQLITE_FCNTL_VFSNAME 12 |
| 853 | #define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13 |
| 854 | #define SQLITE_FCNTL_PRAGMA 14 |
| 855 | |
| 856 | /* |
| 857 | ** CAPI3REF: Mutex Handle |
| 858 | ** |
| 859 | ** The mutex module within SQLite defines [sqlite3_mutex] to be an |
| 860 | ** abstract type for a mutex object. The SQLite core never looks |
| 861 | ** at the internal representation of an [sqlite3_mutex]. It only |
| 862 | ** deals with pointers to the [sqlite3_mutex] object. |
| 863 | ** |
| 864 | ** Mutexes are created using [sqlite3_mutex_alloc()]. |
| 865 | */ |
| 866 | typedef struct sqlite3_mutex sqlite3_mutex; |
| 867 | |
| 868 | /* |
| 869 | ** CAPI3REF: OS Interface Object |
| 870 | ** |
| 871 | ** An instance of the sqlite3_vfs object defines the interface between |
| 872 | ** the SQLite core and the underlying operating system. The "vfs" |
| 873 | ** in the name of the object stands for "virtual file system". See |
| 874 | ** the [VFS | VFS documentation] for further information. |
| 875 | ** |
| 876 | ** The value of the iVersion field is initially 1 but may be larger in |
| 877 | ** future versions of SQLite. Additional fields may be appended to this |
| 878 | ** object when the iVersion value is increased. Note that the structure |
| 879 | ** of the sqlite3_vfs object changes in the transaction between |
| 880 | ** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not |
| 881 | ** modified. |
| 882 | ** |
| 883 | ** The szOsFile field is the size of the subclassed [sqlite3_file] |
| 884 | ** structure used by this VFS. mxPathname is the maximum length of |
| 885 | ** a pathname in this VFS. |
| 886 | ** |
| 887 | ** Registered sqlite3_vfs objects are kept on a linked list formed by |
| 888 | ** the pNext pointer. The [sqlite3_vfs_register()] |
| 889 | ** and [sqlite3_vfs_unregister()] interfaces manage this list |
| 890 | ** in a thread-safe way. The [sqlite3_vfs_find()] interface |
| 891 | ** searches the list. Neither the application code nor the VFS |
| 892 | ** implementation should use the pNext pointer. |
| 893 | ** |
| 894 | ** The pNext field is the only field in the sqlite3_vfs |
| 895 | ** structure that SQLite will ever modify. SQLite will only access |
| 896 | ** or modify this field while holding a particular static mutex. |
| 897 | ** The application should never modify anything within the sqlite3_vfs |
| 898 | ** object once the object has been registered. |
| 899 | ** |
| 900 | ** The zName field holds the name of the VFS module. The name must |
| 901 | ** be unique across all VFS modules. |
| 902 | ** |
| 903 | ** [[sqlite3_vfs.xOpen]] |
| 904 | ** ^SQLite guarantees that the zFilename parameter to xOpen |
| 905 | ** is either a NULL pointer or string obtained |
| 906 | ** from xFullPathname() with an optional suffix added. |
| 907 | ** ^If a suffix is added to the zFilename parameter, it will |
| 908 | ** consist of a single "-" character followed by no more than |
| 909 | ** 11 alphanumeric and/or "-" characters. |
| 910 | ** ^SQLite further guarantees that |
| 911 | ** the string will be valid and unchanged until xClose() is |
| 912 | ** called. Because of the previous sentence, |
| 913 | ** the [sqlite3_file] can safely store a pointer to the |
| 914 | ** filename if it needs to remember the filename for some reason. |
| 915 | ** If the zFilename parameter to xOpen is a NULL pointer then xOpen |
| 916 | ** must invent its own temporary name for the file. ^Whenever the |
| 917 | ** xFilename parameter is NULL it will also be the case that the |
| 918 | ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. |
| 919 | ** |
| 920 | ** The flags argument to xOpen() includes all bits set in |
| 921 | ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] |
| 922 | ** or [sqlite3_open16()] is used, then flags includes at least |
| 923 | ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. |
| 924 | ** If xOpen() opens a file read-only then it sets *pOutFlags to |
| 925 | ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. |
| 926 | ** |
| 927 | ** ^(SQLite will also add one of the following flags to the xOpen() |
| 928 | ** call, depending on the object being opened: |
| 929 | ** |
| 930 | ** <ul> |
| 931 | ** <li> [SQLITE_OPEN_MAIN_DB] |
| 932 | ** <li> [SQLITE_OPEN_MAIN_JOURNAL] |
| 933 | ** <li> [SQLITE_OPEN_TEMP_DB] |
| 934 | ** <li> [SQLITE_OPEN_TEMP_JOURNAL] |
| 935 | ** <li> [SQLITE_OPEN_TRANSIENT_DB] |
| 936 | ** <li> [SQLITE_OPEN_SUBJOURNAL] |
| 937 | ** <li> [SQLITE_OPEN_MASTER_JOURNAL] |
| 938 | ** <li> [SQLITE_OPEN_WAL] |
| 939 | ** </ul>)^ |
| 940 | ** |
| 941 | ** The file I/O implementation can use the object type flags to |
| 942 | ** change the way it deals with files. For example, an application |
| 943 | ** that does not care about crash recovery or rollback might make |
| 944 | ** the open of a journal file a no-op. Writes to this journal would |
| 945 | ** also be no-ops, and any attempt to read the journal would return |
| 946 | ** SQLITE_IOERR. Or the implementation might recognize that a database |
| 947 | ** file will be doing page-aligned sector reads and writes in a random |
| 948 | ** order and set up its I/O subsystem accordingly. |
| 949 | ** |
| 950 | ** SQLite might also add one of the following flags to the xOpen method: |
| 951 | ** |
| 952 | ** <ul> |
| 953 | ** <li> [SQLITE_OPEN_DELETEONCLOSE] |
| 954 | ** <li> [SQLITE_OPEN_EXCLUSIVE] |
| 955 | ** </ul> |
| 956 | ** |
| 957 | ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be |
| 958 | ** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE] |
| 959 | ** will be set for TEMP databases and their journals, transient |
| 960 | ** databases, and subjournals. |
| 961 | ** |
| 962 | ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction |
| 963 | ** with the [SQLITE_OPEN_CREATE] flag, which are both directly |
| 964 | ** analogous to the O_EXCL and O_CREAT flags of the POSIX open() |
| 965 | ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the |
| 966 | ** SQLITE_OPEN_CREATE, is used to indicate that file should always |
| 967 | ** be created, and that it is an error if it already exists. |
| 968 | ** It is <i>not</i> used to indicate the file should be opened |
| 969 | ** for exclusive access. |
| 970 | ** |
| 971 | ** ^At least szOsFile bytes of memory are allocated by SQLite |
| 972 | ** to hold the [sqlite3_file] structure passed as the third |
| 973 | ** argument to xOpen. The xOpen method does not have to |
| 974 | ** allocate the structure; it should just fill it in. Note that |
| 975 | ** the xOpen method must set the sqlite3_file.pMethods to either |
| 976 | ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do |
| 977 | ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods |
| 978 | ** element will be valid after xOpen returns regardless of the success |
| 979 | ** or failure of the xOpen call. |
| 980 | ** |
| 981 | ** [[sqlite3_vfs.xAccess]] |
| 982 | ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] |
| 983 | ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to |
| 984 | ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] |
| 985 | ** to test whether a file is at least readable. The file can be a |
| 986 | ** directory. |
| 987 | ** |
| 988 | ** ^SQLite will always allocate at least mxPathname+1 bytes for the |
| 989 | ** output buffer xFullPathname. The exact size of the output buffer |
| 990 | ** is also passed as a parameter to both methods. If the output buffer |
| 991 | ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is |
| 992 | ** handled as a fatal error by SQLite, vfs implementations should endeavor |
| 993 | ** to prevent this by setting mxPathname to a sufficiently large value. |
| 994 | ** |
| 995 | ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64() |
| 996 | ** interfaces are not strictly a part of the filesystem, but they are |
| 997 | ** included in the VFS structure for completeness. |
| 998 | ** The xRandomness() function attempts to return nBytes bytes |
| 999 | ** of good-quality randomness into zOut. The return value is |
| 1000 | ** the actual number of bytes of randomness obtained. |
| 1001 | ** The xSleep() method causes the calling thread to sleep for at |
| 1002 | ** least the number of microseconds given. ^The xCurrentTime() |
| 1003 | ** method returns a Julian Day Number for the current date and time as |
| 1004 | ** a floating point value. |
| 1005 | ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian |
| 1006 | ** Day Number multiplied by 86400000 (the number of milliseconds in |
| 1007 | ** a 24-hour day). |
| 1008 | ** ^SQLite will use the xCurrentTimeInt64() method to get the current |
| 1009 | ** date and time if that method is available (if iVersion is 2 or |
| 1010 | ** greater and the function pointer is not NULL) and will fall back |
| 1011 | ** to xCurrentTime() if xCurrentTimeInt64() is unavailable. |
| 1012 | ** |
| 1013 | ** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces |
| 1014 | ** are not used by the SQLite core. These optional interfaces are provided |
| 1015 | ** by some VFSes to facilitate testing of the VFS code. By overriding |
| 1016 | ** system calls with functions under its control, a test program can |
| 1017 | ** simulate faults and error conditions that would otherwise be difficult |
| 1018 | ** or impossible to induce. The set of system calls that can be overridden |
| 1019 | ** varies from one VFS to another, and from one version of the same VFS to the |
| 1020 | ** next. Applications that use these interfaces must be prepared for any |
| 1021 | ** or all of these interfaces to be NULL or for their behavior to change |
| 1022 | ** from one release to the next. Applications must not attempt to access |
| 1023 | ** any of these methods if the iVersion of the VFS is less than 3. |
| 1024 | */ |
| 1025 | typedef struct sqlite3_vfs sqlite3_vfs; |
| 1026 | typedef void (*sqlite3_syscall_ptr)(void); |
| 1027 | struct sqlite3_vfs { |
| 1028 | int iVersion; /* Structure version number (currently 3) */ |
| 1029 | int szOsFile; /* Size of subclassed sqlite3_file */ |
| 1030 | int mxPathname; /* Maximum file pathname length */ |
| 1031 | sqlite3_vfs *pNext; /* Next registered VFS */ |
| 1032 | const char *zName; /* Name of this virtual file system */ |
| 1033 | void *pAppData; /* Pointer to application-specific data */ |
| 1034 | int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*, |
| 1035 | int flags, int *pOutFlags); |
| 1036 | int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); |
| 1037 | int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); |
| 1038 | int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); |
| 1039 | void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); |
| 1040 | void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); |
| 1041 | void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void); |
| 1042 | void (*xDlClose)(sqlite3_vfs*, void*); |
| 1043 | int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); |
| 1044 | int (*xSleep)(sqlite3_vfs*, int microseconds); |
| 1045 | int (*xCurrentTime)(sqlite3_vfs*, double*); |
| 1046 | int (*xGetLastError)(sqlite3_vfs*, int, char *); |
| 1047 | /* |
| 1048 | ** The methods above are in version 1 of the sqlite_vfs object |
| 1049 | ** definition. Those that follow are added in version 2 or later |
| 1050 | */ |
| 1051 | int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*); |
| 1052 | /* |
| 1053 | ** The methods above are in versions 1 and 2 of the sqlite_vfs object. |
| 1054 | ** Those below are for version 3 and greater. |
| 1055 | */ |
| 1056 | int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr); |
| 1057 | sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName); |
| 1058 | const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName); |
| 1059 | /* |
| 1060 | ** The methods above are in versions 1 through 3 of the sqlite_vfs object. |
| 1061 | ** New fields may be appended in figure versions. The iVersion |
| 1062 | ** value will increment whenever this happens. |
| 1063 | */ |
| 1064 | }; |
| 1065 | |
| 1066 | /* |
| 1067 | ** CAPI3REF: Flags for the xAccess VFS method |
| 1068 | ** |
| 1069 | ** These integer constants can be used as the third parameter to |
| 1070 | ** the xAccess method of an [sqlite3_vfs] object. They determine |
| 1071 | ** what kind of permissions the xAccess method is looking for. |
| 1072 | ** With SQLITE_ACCESS_EXISTS, the xAccess method |
| 1073 | ** simply checks whether the file exists. |
| 1074 | ** With SQLITE_ACCESS_READWRITE, the xAccess method |
| 1075 | ** checks whether the named directory is both readable and writable |
| 1076 | ** (in other words, if files can be added, removed, and renamed within |
| 1077 | ** the directory). |
| 1078 | ** The SQLITE_ACCESS_READWRITE constant is currently used only by the |
| 1079 | ** [temp_store_directory pragma], though this could change in a future |
| 1080 | ** release of SQLite. |
| 1081 | ** With SQLITE_ACCESS_READ, the xAccess method |
| 1082 | ** checks whether the file is readable. The SQLITE_ACCESS_READ constant is |
| 1083 | ** currently unused, though it might be used in a future release of |
| 1084 | ** SQLite. |
| 1085 | */ |
| 1086 | #define SQLITE_ACCESS_EXISTS 0 |
| 1087 | #define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */ |
| 1088 | #define SQLITE_ACCESS_READ 2 /* Unused */ |
| 1089 | |
| 1090 | /* |
| 1091 | ** CAPI3REF: Flags for the xShmLock VFS method |
| 1092 | ** |
| 1093 | ** These integer constants define the various locking operations |
| 1094 | ** allowed by the xShmLock method of [sqlite3_io_methods]. The |
| 1095 | ** following are the only legal combinations of flags to the |
| 1096 | ** xShmLock method: |
| 1097 | ** |
| 1098 | ** <ul> |
| 1099 | ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED |
| 1100 | ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE |
| 1101 | ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED |
| 1102 | ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE |
| 1103 | ** </ul> |
| 1104 | ** |
| 1105 | ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as |
| 1106 | ** was given no the corresponding lock. |
| 1107 | ** |
| 1108 | ** The xShmLock method can transition between unlocked and SHARED or |
| 1109 | ** between unlocked and EXCLUSIVE. It cannot transition between SHARED |
| 1110 | ** and EXCLUSIVE. |
| 1111 | */ |
| 1112 | #define SQLITE_SHM_UNLOCK 1 |
| 1113 | #define SQLITE_SHM_LOCK 2 |
| 1114 | #define SQLITE_SHM_SHARED 4 |
| 1115 | #define SQLITE_SHM_EXCLUSIVE 8 |
| 1116 | |
| 1117 | /* |
| 1118 | ** CAPI3REF: Maximum xShmLock index |
| 1119 | ** |
| 1120 | ** The xShmLock method on [sqlite3_io_methods] may use values |
| 1121 | ** between 0 and this upper bound as its "offset" argument. |
| 1122 | ** The SQLite core will never attempt to acquire or release a |
| 1123 | ** lock outside of this range |
| 1124 | */ |
| 1125 | #define SQLITE_SHM_NLOCK 8 |
| 1126 | |
| 1127 | |
| 1128 | /* |
| 1129 | ** CAPI3REF: Initialize The SQLite Library |
| 1130 | ** |
| 1131 | ** ^The sqlite3_initialize() routine initializes the |
| 1132 | ** SQLite library. ^The sqlite3_shutdown() routine |
| 1133 | ** deallocates any resources that were allocated by sqlite3_initialize(). |
| 1134 | ** These routines are designed to aid in process initialization and |
| 1135 | ** shutdown on embedded systems. Workstation applications using |
| 1136 | ** SQLite normally do not need to invoke either of these routines. |
| 1137 | ** |
| 1138 | ** A call to sqlite3_initialize() is an "effective" call if it is |
| 1139 | ** the first time sqlite3_initialize() is invoked during the lifetime of |
| 1140 | ** the process, or if it is the first time sqlite3_initialize() is invoked |
| 1141 | ** following a call to sqlite3_shutdown(). ^(Only an effective call |
| 1142 | ** of sqlite3_initialize() does any initialization. All other calls |
| 1143 | ** are harmless no-ops.)^ |
| 1144 | ** |
| 1145 | ** A call to sqlite3_shutdown() is an "effective" call if it is the first |
| 1146 | ** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only |
| 1147 | ** an effective call to sqlite3_shutdown() does any deinitialization. |
| 1148 | ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^ |
| 1149 | ** |
| 1150 | ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown() |
| 1151 | ** is not. The sqlite3_shutdown() interface must only be called from a |
| 1152 | ** single thread. All open [database connections] must be closed and all |
| 1153 | ** other SQLite resources must be deallocated prior to invoking |
| 1154 | ** sqlite3_shutdown(). |
| 1155 | ** |
| 1156 | ** Among other things, ^sqlite3_initialize() will invoke |
| 1157 | ** sqlite3_os_init(). Similarly, ^sqlite3_shutdown() |
| 1158 | ** will invoke sqlite3_os_end(). |
| 1159 | ** |
| 1160 | ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success. |
| 1161 | ** ^If for some reason, sqlite3_initialize() is unable to initialize |
| 1162 | ** the library (perhaps it is unable to allocate a needed resource such |
| 1163 | ** as a mutex) it returns an [error code] other than [SQLITE_OK]. |
| 1164 | ** |
| 1165 | ** ^The sqlite3_initialize() routine is called internally by many other |
| 1166 | ** SQLite interfaces so that an application usually does not need to |
| 1167 | ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] |
| 1168 | ** calls sqlite3_initialize() so the SQLite library will be automatically |
| 1169 | ** initialized when [sqlite3_open()] is called if it has not be initialized |
| 1170 | ** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT] |
| 1171 | ** compile-time option, then the automatic calls to sqlite3_initialize() |
| 1172 | ** are omitted and the application must call sqlite3_initialize() directly |
| 1173 | ** prior to using any other SQLite interface. For maximum portability, |
| 1174 | ** it is recommended that applications always invoke sqlite3_initialize() |
| 1175 | ** directly prior to using any other SQLite interface. Future releases |
| 1176 | ** of SQLite may require this. In other words, the behavior exhibited |
| 1177 | ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the |
| 1178 | ** default behavior in some future release of SQLite. |
| 1179 | ** |
| 1180 | ** The sqlite3_os_init() routine does operating-system specific |
| 1181 | ** initialization of the SQLite library. The sqlite3_os_end() |
| 1182 | ** routine undoes the effect of sqlite3_os_init(). Typical tasks |
| 1183 | ** performed by these routines include allocation or deallocation |
| 1184 | ** of static resources, initialization of global variables, |
| 1185 | ** setting up a default [sqlite3_vfs] module, or setting up |
| 1186 | ** a default configuration using [sqlite3_config()]. |
| 1187 | ** |
| 1188 | ** The application should never invoke either sqlite3_os_init() |
| 1189 | ** or sqlite3_os_end() directly. The application should only invoke |
| 1190 | ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() |
| 1191 | ** interface is called automatically by sqlite3_initialize() and |
| 1192 | ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate |
| 1193 | ** implementations for sqlite3_os_init() and sqlite3_os_end() |
| 1194 | ** are built into SQLite when it is compiled for Unix, Windows, or OS/2. |
| 1195 | ** When [custom builds | built for other platforms] |
| 1196 | ** (using the [SQLITE_OS_OTHER=1] compile-time |
| 1197 | ** option) the application must supply a suitable implementation for |
| 1198 | ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied |
| 1199 | ** implementation of sqlite3_os_init() or sqlite3_os_end() |
| 1200 | ** must return [SQLITE_OK] on success and some other [error code] upon |
| 1201 | ** failure. |
| 1202 | */ |
| 1203 | SQLITE_API int sqlite3_initialize(void); |
| 1204 | SQLITE_API int sqlite3_shutdown(void); |
| 1205 | SQLITE_API int sqlite3_os_init(void); |
| 1206 | SQLITE_API int sqlite3_os_end(void); |
| 1207 | |
| 1208 | /* |
| 1209 | ** CAPI3REF: Configuring The SQLite Library |
| 1210 | ** |
| 1211 | ** The sqlite3_config() interface is used to make global configuration |
| 1212 | ** changes to SQLite in order to tune SQLite to the specific needs of |
| 1213 | ** the application. The default configuration is recommended for most |
| 1214 | ** applications and so this routine is usually not necessary. It is |
| 1215 | ** provided to support rare applications with unusual needs. |
| 1216 | ** |
| 1217 | ** The sqlite3_config() interface is not threadsafe. The application |
| 1218 | ** must insure that no other SQLite interfaces are invoked by other |
| 1219 | ** threads while sqlite3_config() is running. Furthermore, sqlite3_config() |
| 1220 | ** may only be invoked prior to library initialization using |
| 1221 | ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. |
| 1222 | ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before |
| 1223 | ** [sqlite3_shutdown()] then it will return SQLITE_MISUSE. |
| 1224 | ** Note, however, that ^sqlite3_config() can be called as part of the |
| 1225 | ** implementation of an application-defined [sqlite3_os_init()]. |
| 1226 | ** |
| 1227 | ** The first argument to sqlite3_config() is an integer |
| 1228 | ** [configuration option] that determines |
| 1229 | ** what property of SQLite is to be configured. Subsequent arguments |
| 1230 | ** vary depending on the [configuration option] |
| 1231 | ** in the first argument. |
| 1232 | ** |
| 1233 | ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK]. |
| 1234 | ** ^If the option is unknown or SQLite is unable to set the option |
| 1235 | ** then this routine returns a non-zero [error code]. |
| 1236 | */ |
| 1237 | SQLITE_API int sqlite3_config(int, ...); |
| 1238 | |
| 1239 | /* |
| 1240 | ** CAPI3REF: Configure database connections |
| 1241 | ** |
| 1242 | ** The sqlite3_db_config() interface is used to make configuration |
| 1243 | ** changes to a [database connection]. The interface is similar to |
| 1244 | ** [sqlite3_config()] except that the changes apply to a single |
| 1245 | ** [database connection] (specified in the first argument). |
| 1246 | ** |
| 1247 | ** The second argument to sqlite3_db_config(D,V,...) is the |
| 1248 | ** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code |
| 1249 | ** that indicates what aspect of the [database connection] is being configured. |
| 1250 | ** Subsequent arguments vary depending on the configuration verb. |
| 1251 | ** |
| 1252 | ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if |
| 1253 | ** the call is considered successful. |
| 1254 | */ |
| 1255 | SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...); |
| 1256 | |
| 1257 | /* |
| 1258 | ** CAPI3REF: Memory Allocation Routines |
| 1259 | ** |
| 1260 | ** An instance of this object defines the interface between SQLite |
| 1261 | ** and low-level memory allocation routines. |
| 1262 | ** |
| 1263 | ** This object is used in only one place in the SQLite interface. |
| 1264 | ** A pointer to an instance of this object is the argument to |
| 1265 | ** [sqlite3_config()] when the configuration option is |
| 1266 | ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC]. |
| 1267 | ** By creating an instance of this object |
| 1268 | ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC]) |
| 1269 | ** during configuration, an application can specify an alternative |
| 1270 | ** memory allocation subsystem for SQLite to use for all of its |
| 1271 | ** dynamic memory needs. |
| 1272 | ** |
| 1273 | ** Note that SQLite comes with several [built-in memory allocators] |
| 1274 | ** that are perfectly adequate for the overwhelming majority of applications |
| 1275 | ** and that this object is only useful to a tiny minority of applications |
| 1276 | ** with specialized memory allocation requirements. This object is |
| 1277 | ** also used during testing of SQLite in order to specify an alternative |
| 1278 | ** memory allocator that simulates memory out-of-memory conditions in |
| 1279 | ** order to verify that SQLite recovers gracefully from such |
| 1280 | ** conditions. |
| 1281 | ** |
| 1282 | ** The xMalloc, xRealloc, and xFree methods must work like the |
| 1283 | ** malloc(), realloc() and free() functions from the standard C library. |
| 1284 | ** ^SQLite guarantees that the second argument to |
| 1285 | ** xRealloc is always a value returned by a prior call to xRoundup. |
| 1286 | ** |
| 1287 | ** xSize should return the allocated size of a memory allocation |
| 1288 | ** previously obtained from xMalloc or xRealloc. The allocated size |
| 1289 | ** is always at least as big as the requested size but may be larger. |
| 1290 | ** |
| 1291 | ** The xRoundup method returns what would be the allocated size of |
| 1292 | ** a memory allocation given a particular requested size. Most memory |
| 1293 | ** allocators round up memory allocations at least to the next multiple |
| 1294 | ** of 8. Some allocators round up to a larger multiple or to a power of 2. |
| 1295 | ** Every memory allocation request coming in through [sqlite3_malloc()] |
| 1296 | ** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0, |
| 1297 | ** that causes the corresponding memory allocation to fail. |
| 1298 | ** |
| 1299 | ** The xInit method initializes the memory allocator. (For example, |
| 1300 | ** it might allocate any require mutexes or initialize internal data |
| 1301 | ** structures. The xShutdown method is invoked (indirectly) by |
| 1302 | ** [sqlite3_shutdown()] and should deallocate any resources acquired |
| 1303 | ** by xInit. The pAppData pointer is used as the only parameter to |
| 1304 | ** xInit and xShutdown. |
| 1305 | ** |
| 1306 | ** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes |
| 1307 | ** the xInit method, so the xInit method need not be threadsafe. The |
| 1308 | ** xShutdown method is only called from [sqlite3_shutdown()] so it does |
| 1309 | ** not need to be threadsafe either. For all other methods, SQLite |
| 1310 | ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the |
| 1311 | ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which |
| 1312 | ** it is by default) and so the methods are automatically serialized. |
| 1313 | ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other |
| 1314 | ** methods must be threadsafe or else make their own arrangements for |
| 1315 | ** serialization. |
| 1316 | ** |
| 1317 | ** SQLite will never invoke xInit() more than once without an intervening |
| 1318 | ** call to xShutdown(). |
| 1319 | */ |
| 1320 | typedef struct sqlite3_mem_methods sqlite3_mem_methods; |
| 1321 | struct sqlite3_mem_methods { |
| 1322 | void *(*xMalloc)(int); /* Memory allocation function */ |
| 1323 | void (*xFree)(void*); /* Free a prior allocation */ |
| 1324 | void *(*xRealloc)(void*,int); /* Resize an allocation */ |
| 1325 | int (*xSize)(void*); /* Return the size of an allocation */ |
| 1326 | int (*xRoundup)(int); /* Round up request size to allocation size */ |
| 1327 | int (*xInit)(void*); /* Initialize the memory allocator */ |
| 1328 | void (*xShutdown)(void*); /* Deinitialize the memory allocator */ |
| 1329 | void *pAppData; /* Argument to xInit() and xShutdown() */ |
| 1330 | }; |
| 1331 | |
| 1332 | /* |
| 1333 | ** CAPI3REF: Configuration Options |
| 1334 | ** KEYWORDS: {configuration option} |
| 1335 | ** |
| 1336 | ** These constants are the available integer configuration options that |
| 1337 | ** can be passed as the first argument to the [sqlite3_config()] interface. |
| 1338 | ** |
| 1339 | ** New configuration options may be added in future releases of SQLite. |
| 1340 | ** Existing configuration options might be discontinued. Applications |
| 1341 | ** should check the return code from [sqlite3_config()] to make sure that |
| 1342 | ** the call worked. The [sqlite3_config()] interface will return a |
| 1343 | ** non-zero [error code] if a discontinued or unsupported configuration option |
| 1344 | ** is invoked. |
| 1345 | ** |
| 1346 | ** <dl> |
| 1347 | ** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt> |
| 1348 | ** <dd>There are no arguments to this option. ^This option sets the |
| 1349 | ** [threading mode] to Single-thread. In other words, it disables |
| 1350 | ** all mutexing and puts SQLite into a mode where it can only be used |
| 1351 | ** by a single thread. ^If SQLite is compiled with |
| 1352 | ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
| 1353 | ** it is not possible to change the [threading mode] from its default |
| 1354 | ** value of Single-thread and so [sqlite3_config()] will return |
| 1355 | ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD |
| 1356 | ** configuration option.</dd> |
| 1357 | ** |
| 1358 | ** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt> |
| 1359 | ** <dd>There are no arguments to this option. ^This option sets the |
| 1360 | ** [threading mode] to Multi-thread. In other words, it disables |
| 1361 | ** mutexing on [database connection] and [prepared statement] objects. |
| 1362 | ** The application is responsible for serializing access to |
| 1363 | ** [database connections] and [prepared statements]. But other mutexes |
| 1364 | ** are enabled so that SQLite will be safe to use in a multi-threaded |
| 1365 | ** environment as long as no two threads attempt to use the same |
| 1366 | ** [database connection] at the same time. ^If SQLite is compiled with |
| 1367 | ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
| 1368 | ** it is not possible to set the Multi-thread [threading mode] and |
| 1369 | ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the |
| 1370 | ** SQLITE_CONFIG_MULTITHREAD configuration option.</dd> |
| 1371 | ** |
| 1372 | ** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt> |
| 1373 | ** <dd>There are no arguments to this option. ^This option sets the |
| 1374 | ** [threading mode] to Serialized. In other words, this option enables |
| 1375 | ** all mutexes including the recursive |
| 1376 | ** mutexes on [database connection] and [prepared statement] objects. |
| 1377 | ** In this mode (which is the default when SQLite is compiled with |
| 1378 | ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access |
| 1379 | ** to [database connections] and [prepared statements] so that the |
| 1380 | ** application is free to use the same [database connection] or the |
| 1381 | ** same [prepared statement] in different threads at the same time. |
| 1382 | ** ^If SQLite is compiled with |
| 1383 | ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
| 1384 | ** it is not possible to set the Serialized [threading mode] and |
| 1385 | ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the |
| 1386 | ** SQLITE_CONFIG_SERIALIZED configuration option.</dd> |
| 1387 | ** |
| 1388 | ** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt> |
| 1389 | ** <dd> ^(This option takes a single argument which is a pointer to an |
| 1390 | ** instance of the [sqlite3_mem_methods] structure. The argument specifies |
| 1391 | ** alternative low-level memory allocation routines to be used in place of |
| 1392 | ** the memory allocation routines built into SQLite.)^ ^SQLite makes |
| 1393 | ** its own private copy of the content of the [sqlite3_mem_methods] structure |
| 1394 | ** before the [sqlite3_config()] call returns.</dd> |
| 1395 | ** |
| 1396 | ** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt> |
| 1397 | ** <dd> ^(This option takes a single argument which is a pointer to an |
| 1398 | ** instance of the [sqlite3_mem_methods] structure. The [sqlite3_mem_methods] |
| 1399 | ** structure is filled with the currently defined memory allocation routines.)^ |
| 1400 | ** This option can be used to overload the default memory allocation |
| 1401 | ** routines with a wrapper that simulations memory allocation failure or |
| 1402 | ** tracks memory usage, for example. </dd> |
| 1403 | ** |
| 1404 | ** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt> |
| 1405 | ** <dd> ^This option takes single argument of type int, interpreted as a |
| 1406 | ** boolean, which enables or disables the collection of memory allocation |
| 1407 | ** statistics. ^(When memory allocation statistics are disabled, the |
| 1408 | ** following SQLite interfaces become non-operational: |
| 1409 | ** <ul> |
| 1410 | ** <li> [sqlite3_memory_used()] |
| 1411 | ** <li> [sqlite3_memory_highwater()] |
| 1412 | ** <li> [sqlite3_soft_heap_limit64()] |
| 1413 | ** <li> [sqlite3_status()] |
| 1414 | ** </ul>)^ |
| 1415 | ** ^Memory allocation statistics are enabled by default unless SQLite is |
| 1416 | ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory |
| 1417 | ** allocation statistics are disabled by default. |
| 1418 | ** </dd> |
| 1419 | ** |
| 1420 | ** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt> |
| 1421 | ** <dd> ^This option specifies a static memory buffer that SQLite can use for |
| 1422 | ** scratch memory. There are three arguments: A pointer an 8-byte |
| 1423 | ** aligned memory buffer from which the scratch allocations will be |
| 1424 | ** drawn, the size of each scratch allocation (sz), |
| 1425 | ** and the maximum number of scratch allocations (N). The sz |
| 1426 | ** argument must be a multiple of 16. |
| 1427 | ** The first argument must be a pointer to an 8-byte aligned buffer |
| 1428 | ** of at least sz*N bytes of memory. |
| 1429 | ** ^SQLite will use no more than two scratch buffers per thread. So |
| 1430 | ** N should be set to twice the expected maximum number of threads. |
| 1431 | ** ^SQLite will never require a scratch buffer that is more than 6 |
| 1432 | ** times the database page size. ^If SQLite needs needs additional |
| 1433 | ** scratch memory beyond what is provided by this configuration option, then |
| 1434 | ** [sqlite3_malloc()] will be used to obtain the memory needed.</dd> |
| 1435 | ** |
| 1436 | ** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt> |
| 1437 | ** <dd> ^This option specifies a static memory buffer that SQLite can use for |
| 1438 | ** the database page cache with the default page cache implementation. |
| 1439 | ** This configuration should not be used if an application-define page |
| 1440 | ** cache implementation is loaded using the SQLITE_CONFIG_PCACHE2 option. |
| 1441 | ** There are three arguments to this option: A pointer to 8-byte aligned |
| 1442 | ** memory, the size of each page buffer (sz), and the number of pages (N). |
| 1443 | ** The sz argument should be the size of the largest database page |
| 1444 | ** (a power of two between 512 and 32768) plus a little extra for each |
| 1445 | ** page header. ^The page header size is 20 to 40 bytes depending on |
| 1446 | ** the host architecture. ^It is harmless, apart from the wasted memory, |
| 1447 | ** to make sz a little too large. The first |
| 1448 | ** argument should point to an allocation of at least sz*N bytes of memory. |
| 1449 | ** ^SQLite will use the memory provided by the first argument to satisfy its |
| 1450 | ** memory needs for the first N pages that it adds to cache. ^If additional |
| 1451 | ** page cache memory is needed beyond what is provided by this option, then |
| 1452 | ** SQLite goes to [sqlite3_malloc()] for the additional storage space. |
| 1453 | ** The pointer in the first argument must |
| 1454 | ** be aligned to an 8-byte boundary or subsequent behavior of SQLite |
| 1455 | ** will be undefined.</dd> |
| 1456 | ** |
| 1457 | ** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt> |
| 1458 | ** <dd> ^This option specifies a static memory buffer that SQLite will use |
| 1459 | ** for all of its dynamic memory allocation needs beyond those provided |
| 1460 | ** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE]. |
| 1461 | ** There are three arguments: An 8-byte aligned pointer to the memory, |
| 1462 | ** the number of bytes in the memory buffer, and the minimum allocation size. |
| 1463 | ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts |
| 1464 | ** to using its default memory allocator (the system malloc() implementation), |
| 1465 | ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the |
| 1466 | ** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or |
| 1467 | ** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory |
| 1468 | ** allocator is engaged to handle all of SQLites memory allocation needs. |
| 1469 | ** The first pointer (the memory pointer) must be aligned to an 8-byte |
| 1470 | ** boundary or subsequent behavior of SQLite will be undefined. |
| 1471 | ** The minimum allocation size is capped at 2**12. Reasonable values |
| 1472 | ** for the minimum allocation size are 2**5 through 2**8.</dd> |
| 1473 | ** |
| 1474 | ** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt> |
| 1475 | ** <dd> ^(This option takes a single argument which is a pointer to an |
| 1476 | ** instance of the [sqlite3_mutex_methods] structure. The argument specifies |
| 1477 | ** alternative low-level mutex routines to be used in place |
| 1478 | ** the mutex routines built into SQLite.)^ ^SQLite makes a copy of the |
| 1479 | ** content of the [sqlite3_mutex_methods] structure before the call to |
| 1480 | ** [sqlite3_config()] returns. ^If SQLite is compiled with |
| 1481 | ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
| 1482 | ** the entire mutexing subsystem is omitted from the build and hence calls to |
| 1483 | ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will |
| 1484 | ** return [SQLITE_ERROR].</dd> |
| 1485 | ** |
| 1486 | ** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt> |
| 1487 | ** <dd> ^(This option takes a single argument which is a pointer to an |
| 1488 | ** instance of the [sqlite3_mutex_methods] structure. The |
| 1489 | ** [sqlite3_mutex_methods] |
| 1490 | ** structure is filled with the currently defined mutex routines.)^ |
| 1491 | ** This option can be used to overload the default mutex allocation |
| 1492 | ** routines with a wrapper used to track mutex usage for performance |
| 1493 | ** profiling or testing, for example. ^If SQLite is compiled with |
| 1494 | ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
| 1495 | ** the entire mutexing subsystem is omitted from the build and hence calls to |
| 1496 | ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will |
| 1497 | ** return [SQLITE_ERROR].</dd> |
| 1498 | ** |
| 1499 | ** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt> |
| 1500 | ** <dd> ^(This option takes two arguments that determine the default |
| 1501 | ** memory allocation for the lookaside memory allocator on each |
| 1502 | ** [database connection]. The first argument is the |
| 1503 | ** size of each lookaside buffer slot and the second is the number of |
| 1504 | ** slots allocated to each database connection.)^ ^(This option sets the |
| 1505 | ** <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE] |
| 1506 | ** verb to [sqlite3_db_config()] can be used to change the lookaside |
| 1507 | ** configuration on individual connections.)^ </dd> |
| 1508 | ** |
| 1509 | ** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt> |
| 1510 | ** <dd> ^(This option takes a single argument which is a pointer to |
| 1511 | ** an [sqlite3_pcache_methods2] object. This object specifies the interface |
| 1512 | ** to a custom page cache implementation.)^ ^SQLite makes a copy of the |
| 1513 | ** object and uses it for page cache memory allocations.</dd> |
| 1514 | ** |
| 1515 | ** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt> |
| 1516 | ** <dd> ^(This option takes a single argument which is a pointer to an |
| 1517 | ** [sqlite3_pcache_methods2] object. SQLite copies of the current |
| 1518 | ** page cache implementation into that object.)^ </dd> |
| 1519 | ** |
| 1520 | ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt> |
| 1521 | ** <dd> ^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a |
| 1522 | ** function with a call signature of void(*)(void*,int,const char*), |
| 1523 | ** and a pointer to void. ^If the function pointer is not NULL, it is |
| 1524 | ** invoked by [sqlite3_log()] to process each logging event. ^If the |
| 1525 | ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op. |
| 1526 | ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is |
| 1527 | ** passed through as the first parameter to the application-defined logger |
| 1528 | ** function whenever that function is invoked. ^The second parameter to |
| 1529 | ** the logger function is a copy of the first parameter to the corresponding |
| 1530 | ** [sqlite3_log()] call and is intended to be a [result code] or an |
| 1531 | ** [extended result code]. ^The third parameter passed to the logger is |
| 1532 | ** log message after formatting via [sqlite3_snprintf()]. |
| 1533 | ** The SQLite logging interface is not reentrant; the logger function |
| 1534 | ** supplied by the application must not invoke any SQLite interface. |
| 1535 | ** In a multi-threaded application, the application-defined logger |
| 1536 | ** function must be threadsafe. </dd> |
| 1537 | ** |
| 1538 | ** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI |
| 1539 | ** <dd> This option takes a single argument of type int. If non-zero, then |
| 1540 | ** URI handling is globally enabled. If the parameter is zero, then URI handling |
| 1541 | ** is globally disabled. If URI handling is globally enabled, all filenames |
| 1542 | ** passed to [sqlite3_open()], [sqlite3_open_v2()], [sqlite3_open16()] or |
| 1543 | ** specified as part of [ATTACH] commands are interpreted as URIs, regardless |
| 1544 | ** of whether or not the [SQLITE_OPEN_URI] flag is set when the database |
| 1545 | ** connection is opened. If it is globally disabled, filenames are |
| 1546 | ** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the |
| 1547 | ** database connection is opened. By default, URI handling is globally |
| 1548 | ** disabled. The default value may be changed by compiling with the |
| 1549 | ** [SQLITE_USE_URI] symbol defined. |
| 1550 | ** |
| 1551 | ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]] |
| 1552 | ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE |
| 1553 | ** <dd> These options are obsolete and should not be used by new code. |
| 1554 | ** They are retained for backwards compatibility but are now no-ops. |
| 1555 | ** </dl> |
| 1556 | */ |
| 1557 | #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ |
| 1558 | #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ |
| 1559 | #define SQLITE_CONFIG_SERIALIZED 3 /* nil */ |
| 1560 | #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ |
| 1561 | #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ |
| 1562 | #define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */ |
| 1563 | #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ |
| 1564 | #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ |
| 1565 | #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ |
| 1566 | #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ |
| 1567 | #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ |
| 1568 | /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ |
| 1569 | #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ |
| 1570 | #define SQLITE_CONFIG_PCACHE 14 /* no-op */ |
| 1571 | #define SQLITE_CONFIG_GETPCACHE 15 /* no-op */ |
| 1572 | #define SQLITE_CONFIG_LOG 16 /* xFunc, void* */ |
| 1573 | #define SQLITE_CONFIG_URI 17 /* int */ |
| 1574 | #define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */ |
| 1575 | #define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */ |
| 1576 | |
| 1577 | /* |
| 1578 | ** CAPI3REF: Database Connection Configuration Options |
| 1579 | ** |
| 1580 | ** These constants are the available integer configuration options that |
| 1581 | ** can be passed as the second argument to the [sqlite3_db_config()] interface. |
| 1582 | ** |
| 1583 | ** New configuration options may be added in future releases of SQLite. |
| 1584 | ** Existing configuration options might be discontinued. Applications |
| 1585 | ** should check the return code from [sqlite3_db_config()] to make sure that |
| 1586 | ** the call worked. ^The [sqlite3_db_config()] interface will return a |
| 1587 | ** non-zero [error code] if a discontinued or unsupported configuration option |
| 1588 | ** is invoked. |
| 1589 | ** |
| 1590 | ** <dl> |
| 1591 | ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt> |
| 1592 | ** <dd> ^This option takes three additional arguments that determine the |
| 1593 | ** [lookaside memory allocator] configuration for the [database connection]. |
| 1594 | ** ^The first argument (the third parameter to [sqlite3_db_config()] is a |
| 1595 | ** pointer to a memory buffer to use for lookaside memory. |
| 1596 | ** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb |
| 1597 | ** may be NULL in which case SQLite will allocate the |
| 1598 | ** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the |
| 1599 | ** size of each lookaside buffer slot. ^The third argument is the number of |
| 1600 | ** slots. The size of the buffer in the first argument must be greater than |
| 1601 | ** or equal to the product of the second and third arguments. The buffer |
| 1602 | ** must be aligned to an 8-byte boundary. ^If the second argument to |
| 1603 | ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally |
| 1604 | ** rounded down to the next smaller multiple of 8. ^(The lookaside memory |
| 1605 | ** configuration for a database connection can only be changed when that |
| 1606 | ** connection is not currently using lookaside memory, or in other words |
| 1607 | ** when the "current value" returned by |
| 1608 | ** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero. |
| 1609 | ** Any attempt to change the lookaside memory configuration when lookaside |
| 1610 | ** memory is in use leaves the configuration unchanged and returns |
| 1611 | ** [SQLITE_BUSY].)^</dd> |
| 1612 | ** |
| 1613 | ** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt> |
| 1614 | ** <dd> ^This option is used to enable or disable the enforcement of |
| 1615 | ** [foreign key constraints]. There should be two additional arguments. |
| 1616 | ** The first argument is an integer which is 0 to disable FK enforcement, |
| 1617 | ** positive to enable FK enforcement or negative to leave FK enforcement |
| 1618 | ** unchanged. The second parameter is a pointer to an integer into which |
| 1619 | ** is written 0 or 1 to indicate whether FK enforcement is off or on |
| 1620 | ** following this call. The second parameter may be a NULL pointer, in |
| 1621 | ** which case the FK enforcement setting is not reported back. </dd> |
| 1622 | ** |
| 1623 | ** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt> |
| 1624 | ** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers]. |
| 1625 | ** There should be two additional arguments. |
| 1626 | ** The first argument is an integer which is 0 to disable triggers, |
| 1627 | ** positive to enable triggers or negative to leave the setting unchanged. |
| 1628 | ** The second parameter is a pointer to an integer into which |
| 1629 | ** is written 0 or 1 to indicate whether triggers are disabled or enabled |
| 1630 | ** following this call. The second parameter may be a NULL pointer, in |
| 1631 | ** which case the trigger setting is not reported back. </dd> |
| 1632 | ** |
| 1633 | ** </dl> |
| 1634 | */ |
| 1635 | #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ |
| 1636 | #define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */ |
| 1637 | #define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */ |
| 1638 | |
| 1639 | |
| 1640 | /* |
| 1641 | ** CAPI3REF: Enable Or Disable Extended Result Codes |
| 1642 | ** |
| 1643 | ** ^The sqlite3_extended_result_codes() routine enables or disables the |
| 1644 | ** [extended result codes] feature of SQLite. ^The extended result |
| 1645 | ** codes are disabled by default for historical compatibility. |
| 1646 | */ |
| 1647 | SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff); |
| 1648 | |
| 1649 | /* |
| 1650 | ** CAPI3REF: Last Insert Rowid |
| 1651 | ** |
| 1652 | ** ^Each entry in an SQLite table has a unique 64-bit signed |
| 1653 | ** integer key called the [ROWID | "rowid"]. ^The rowid is always available |
| 1654 | ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those |
| 1655 | ** names are not also used by explicitly declared columns. ^If |
| 1656 | ** the table has a column of type [INTEGER PRIMARY KEY] then that column |
| 1657 | ** is another alias for the rowid. |
| 1658 | ** |
| 1659 | ** ^This routine returns the [rowid] of the most recent |
| 1660 | ** successful [INSERT] into the database from the [database connection] |
| 1661 | ** in the first argument. ^As of SQLite version 3.7.7, this routines |
| 1662 | ** records the last insert rowid of both ordinary tables and [virtual tables]. |
| 1663 | ** ^If no successful [INSERT]s |
| 1664 | ** have ever occurred on that database connection, zero is returned. |
| 1665 | ** |
| 1666 | ** ^(If an [INSERT] occurs within a trigger or within a [virtual table] |
| 1667 | ** method, then this routine will return the [rowid] of the inserted |
| 1668 | ** row as long as the trigger or virtual table method is running. |
| 1669 | ** But once the trigger or virtual table method ends, the value returned |
| 1670 | ** by this routine reverts to what it was before the trigger or virtual |
| 1671 | ** table method began.)^ |
| 1672 | ** |
| 1673 | ** ^An [INSERT] that fails due to a constraint violation is not a |
| 1674 | ** successful [INSERT] and does not change the value returned by this |
| 1675 | ** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, |
| 1676 | ** and INSERT OR ABORT make no changes to the return value of this |
| 1677 | ** routine when their insertion fails. ^(When INSERT OR REPLACE |
| 1678 | ** encounters a constraint violation, it does not fail. The |
| 1679 | ** INSERT continues to completion after deleting rows that caused |
| 1680 | ** the constraint problem so INSERT OR REPLACE will always change |
| 1681 | ** the return value of this interface.)^ |
| 1682 | ** |
| 1683 | ** ^For the purposes of this routine, an [INSERT] is considered to |
| 1684 | ** be successful even if it is subsequently rolled back. |
| 1685 | ** |
| 1686 | ** This function is accessible to SQL statements via the |
| 1687 | ** [last_insert_rowid() SQL function]. |
| 1688 | ** |
| 1689 | ** If a separate thread performs a new [INSERT] on the same |
| 1690 | ** database connection while the [sqlite3_last_insert_rowid()] |
| 1691 | ** function is running and thus changes the last insert [rowid], |
| 1692 | ** then the value returned by [sqlite3_last_insert_rowid()] is |
| 1693 | ** unpredictable and might not equal either the old or the new |
| 1694 | ** last insert [rowid]. |
| 1695 | */ |
| 1696 | SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); |
| 1697 | |
| 1698 | /* |
| 1699 | ** CAPI3REF: Count The Number Of Rows Modified |
| 1700 | ** |
| 1701 | ** ^This function returns the number of database rows that were changed |
| 1702 | ** or inserted or deleted by the most recently completed SQL statement |
| 1703 | ** on the [database connection] specified by the first parameter. |
| 1704 | ** ^(Only changes that are directly specified by the [INSERT], [UPDATE], |
| 1705 | ** or [DELETE] statement are counted. Auxiliary changes caused by |
| 1706 | ** triggers or [foreign key actions] are not counted.)^ Use the |
| 1707 | ** [sqlite3_total_changes()] function to find the total number of changes |
| 1708 | ** including changes caused by triggers and foreign key actions. |
| 1709 | ** |
| 1710 | ** ^Changes to a view that are simulated by an [INSTEAD OF trigger] |
| 1711 | ** are not counted. Only real table changes are counted. |
| 1712 | ** |
| 1713 | ** ^(A "row change" is a change to a single row of a single table |
| 1714 | ** caused by an INSERT, DELETE, or UPDATE statement. Rows that |
| 1715 | ** are changed as side effects of [REPLACE] constraint resolution, |
| 1716 | ** rollback, ABORT processing, [DROP TABLE], or by any other |
| 1717 | ** mechanisms do not count as direct row changes.)^ |
| 1718 | ** |
| 1719 | ** A "trigger context" is a scope of execution that begins and |
| 1720 | ** ends with the script of a [CREATE TRIGGER | trigger]. |
| 1721 | ** Most SQL statements are |
| 1722 | ** evaluated outside of any trigger. This is the "top level" |
| 1723 | ** trigger context. If a trigger fires from the top level, a |
| 1724 | ** new trigger context is entered for the duration of that one |
| 1725 | ** trigger. Subtriggers create subcontexts for their duration. |
| 1726 | ** |
| 1727 | ** ^Calling [sqlite3_exec()] or [sqlite3_step()] recursively does |
| 1728 | ** not create a new trigger context. |
| 1729 | ** |
| 1730 | ** ^This function returns the number of direct row changes in the |
| 1731 | ** most recent INSERT, UPDATE, or DELETE statement within the same |
| 1732 | ** trigger context. |
| 1733 | ** |
| 1734 | ** ^Thus, when called from the top level, this function returns the |
| 1735 | ** number of changes in the most recent INSERT, UPDATE, or DELETE |
| 1736 | ** that also occurred at the top level. ^(Within the body of a trigger, |
| 1737 | ** the sqlite3_changes() interface can be called to find the number of |
| 1738 | ** changes in the most recently completed INSERT, UPDATE, or DELETE |
| 1739 | ** statement within the body of the same trigger. |
| 1740 | ** However, the number returned does not include changes |
| 1741 | ** caused by subtriggers since those have their own context.)^ |
| 1742 | ** |
| 1743 | ** See also the [sqlite3_total_changes()] interface, the |
| 1744 | ** [count_changes pragma], and the [changes() SQL function]. |
| 1745 | ** |
| 1746 | ** If a separate thread makes changes on the same database connection |
| 1747 | ** while [sqlite3_changes()] is running then the value returned |
| 1748 | ** is unpredictable and not meaningful. |
| 1749 | */ |
| 1750 | SQLITE_API int sqlite3_changes(sqlite3*); |
| 1751 | |
| 1752 | /* |
| 1753 | ** CAPI3REF: Total Number Of Rows Modified |
| 1754 | ** |
| 1755 | ** ^This function returns the number of row changes caused by [INSERT], |
| 1756 | ** [UPDATE] or [DELETE] statements since the [database connection] was opened. |
| 1757 | ** ^(The count returned by sqlite3_total_changes() includes all changes |
| 1758 | ** from all [CREATE TRIGGER | trigger] contexts and changes made by |
| 1759 | ** [foreign key actions]. However, |
| 1760 | ** the count does not include changes used to implement [REPLACE] constraints, |
| 1761 | ** do rollbacks or ABORT processing, or [DROP TABLE] processing. The |
| 1762 | ** count does not include rows of views that fire an [INSTEAD OF trigger], |
| 1763 | ** though if the INSTEAD OF trigger makes changes of its own, those changes |
| 1764 | ** are counted.)^ |
| 1765 | ** ^The sqlite3_total_changes() function counts the changes as soon as |
| 1766 | ** the statement that makes them is completed (when the statement handle |
| 1767 | ** is passed to [sqlite3_reset()] or [sqlite3_finalize()]). |
| 1768 | ** |
| 1769 | ** See also the [sqlite3_changes()] interface, the |
| 1770 | ** [count_changes pragma], and the [total_changes() SQL function]. |
| 1771 | ** |
| 1772 | ** If a separate thread makes changes on the same database connection |
| 1773 | ** while [sqlite3_total_changes()] is running then the value |
| 1774 | ** returned is unpredictable and not meaningful. |
| 1775 | */ |
| 1776 | SQLITE_API int sqlite3_total_changes(sqlite3*); |
| 1777 | |
| 1778 | /* |
| 1779 | ** CAPI3REF: Interrupt A Long-Running Query |
| 1780 | ** |
| 1781 | ** ^This function causes any pending database operation to abort and |
| 1782 | ** return at its earliest opportunity. This routine is typically |
| 1783 | ** called in response to a user action such as pressing "Cancel" |
| 1784 | ** or Ctrl-C where the user wants a long query operation to halt |
| 1785 | ** immediately. |
| 1786 | ** |
| 1787 | ** ^It is safe to call this routine from a thread different from the |
| 1788 | ** thread that is currently running the database operation. But it |
| 1789 | ** is not safe to call this routine with a [database connection] that |
| 1790 | ** is closed or might close before sqlite3_interrupt() returns. |
| 1791 | ** |
| 1792 | ** ^If an SQL operation is very nearly finished at the time when |
| 1793 | ** sqlite3_interrupt() is called, then it might not have an opportunity |
| 1794 | ** to be interrupted and might continue to completion. |
| 1795 | ** |
| 1796 | ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. |
| 1797 | ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE |
| 1798 | ** that is inside an explicit transaction, then the entire transaction |
| 1799 | ** will be rolled back automatically. |
| 1800 | ** |
| 1801 | ** ^The sqlite3_interrupt(D) call is in effect until all currently running |
| 1802 | ** SQL statements on [database connection] D complete. ^Any new SQL statements |
| 1803 | ** that are started after the sqlite3_interrupt() call and before the |
| 1804 | ** running statements reaches zero are interrupted as if they had been |
| 1805 | ** running prior to the sqlite3_interrupt() call. ^New SQL statements |
| 1806 | ** that are started after the running statement count reaches zero are |
| 1807 | ** not effected by the sqlite3_interrupt(). |
| 1808 | ** ^A call to sqlite3_interrupt(D) that occurs when there are no running |
| 1809 | ** SQL statements is a no-op and has no effect on SQL statements |
| 1810 | ** that are started after the sqlite3_interrupt() call returns. |
| 1811 | ** |
| 1812 | ** If the database connection closes while [sqlite3_interrupt()] |
| 1813 | ** is running then bad things will likely happen. |
| 1814 | */ |
| 1815 | SQLITE_API void sqlite3_interrupt(sqlite3*); |
| 1816 | |
| 1817 | /* |
| 1818 | ** CAPI3REF: Determine If An SQL Statement Is Complete |
| 1819 | ** |
| 1820 | ** These routines are useful during command-line input to determine if the |
| 1821 | ** currently entered text seems to form a complete SQL statement or |
| 1822 | ** if additional input is needed before sending the text into |
| 1823 | ** SQLite for parsing. ^These routines return 1 if the input string |
| 1824 | ** appears to be a complete SQL statement. ^A statement is judged to be |
| 1825 | ** complete if it ends with a semicolon token and is not a prefix of a |
| 1826 | ** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within |
| 1827 | ** string literals or quoted identifier names or comments are not |
| 1828 | ** independent tokens (they are part of the token in which they are |
| 1829 | ** embedded) and thus do not count as a statement terminator. ^Whitespace |
| 1830 | ** and comments that follow the final semicolon are ignored. |
| 1831 | ** |
| 1832 | ** ^These routines return 0 if the statement is incomplete. ^If a |
| 1833 | ** memory allocation fails, then SQLITE_NOMEM is returned. |
| 1834 | ** |
| 1835 | ** ^These routines do not parse the SQL statements thus |
| 1836 | ** will not detect syntactically incorrect SQL. |
| 1837 | ** |
| 1838 | ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior |
| 1839 | ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked |
| 1840 | ** automatically by sqlite3_complete16(). If that initialization fails, |
| 1841 | ** then the return value from sqlite3_complete16() will be non-zero |
| 1842 | ** regardless of whether or not the input SQL is complete.)^ |
| 1843 | ** |
| 1844 | ** The input to [sqlite3_complete()] must be a zero-terminated |
| 1845 | ** UTF-8 string. |
| 1846 | ** |
| 1847 | ** The input to [sqlite3_complete16()] must be a zero-terminated |
| 1848 | ** UTF-16 string in native byte order. |
| 1849 | */ |
| 1850 | SQLITE_API int sqlite3_complete(const char *sql); |
| 1851 | SQLITE_API int sqlite3_complete16(const void *sql); |
| 1852 | |
| 1853 | /* |
| 1854 | ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors |
| 1855 | ** |
| 1856 | ** ^This routine sets a callback function that might be invoked whenever |
| 1857 | ** an attempt is made to open a database table that another thread |
| 1858 | ** or process has locked. |
| 1859 | ** |
| 1860 | ** ^If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] |
| 1861 | ** is returned immediately upon encountering the lock. ^If the busy callback |
| 1862 | ** is not NULL, then the callback might be invoked with two arguments. |
| 1863 | ** |
| 1864 | ** ^The first argument to the busy handler is a copy of the void* pointer which |
| 1865 | ** is the third argument to sqlite3_busy_handler(). ^The second argument to |
| 1866 | ** the busy handler callback is the number of times that the busy handler has |
| 1867 | ** been invoked for this locking event. ^If the |
| 1868 | ** busy callback returns 0, then no additional attempts are made to |
| 1869 | ** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned. |
| 1870 | ** ^If the callback returns non-zero, then another attempt |
| 1871 | ** is made to open the database for reading and the cycle repeats. |
| 1872 | ** |
| 1873 | ** The presence of a busy handler does not guarantee that it will be invoked |
| 1874 | ** when there is lock contention. ^If SQLite determines that invoking the busy |
| 1875 | ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] |
| 1876 | ** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler. |
| 1877 | ** Consider a scenario where one process is holding a read lock that |
| 1878 | ** it is trying to promote to a reserved lock and |
| 1879 | ** a second process is holding a reserved lock that it is trying |
| 1880 | ** to promote to an exclusive lock. The first process cannot proceed |
| 1881 | ** because it is blocked by the second and the second process cannot |
| 1882 | ** proceed because it is blocked by the first. If both processes |
| 1883 | ** invoke the busy handlers, neither will make any progress. Therefore, |
| 1884 | ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this |
| 1885 | ** will induce the first process to release its read lock and allow |
| 1886 | ** the second process to proceed. |
| 1887 | ** |
| 1888 | ** ^The default busy callback is NULL. |
| 1889 | ** |
| 1890 | ** ^The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED] |
| 1891 | ** when SQLite is in the middle of a large transaction where all the |
| 1892 | ** changes will not fit into the in-memory cache. SQLite will |
| 1893 | ** already hold a RESERVED lock on the database file, but it needs |
| 1894 | ** to promote this lock to EXCLUSIVE so that it can spill cache |
| 1895 | ** pages into the database file without harm to concurrent |
| 1896 | ** readers. ^If it is unable to promote the lock, then the in-memory |
| 1897 | ** cache will be left in an inconsistent state and so the error |
| 1898 | ** code is promoted from the relatively benign [SQLITE_BUSY] to |
| 1899 | ** the more severe [SQLITE_IOERR_BLOCKED]. ^This error code promotion |
| 1900 | ** forces an automatic rollback of the changes. See the |
| 1901 | ** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError"> |
| 1902 | ** CorruptionFollowingBusyError</a> wiki page for a discussion of why |
| 1903 | ** this is important. |
| 1904 | ** |
| 1905 | ** ^(There can only be a single busy handler defined for each |
| 1906 | ** [database connection]. Setting a new busy handler clears any |
| 1907 | ** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()] |
| 1908 | ** will also set or clear the busy handler. |
| 1909 | ** |
| 1910 | ** The busy callback should not take any actions which modify the |
| 1911 | ** database connection that invoked the busy handler. Any such actions |
| 1912 | ** result in undefined behavior. |
| 1913 | ** |
| 1914 | ** A busy handler must not close the database connection |
| 1915 | ** or [prepared statement] that invoked the busy handler. |
| 1916 | */ |
| 1917 | SQLITE_API int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*); |
| 1918 | |
| 1919 | /* |
| 1920 | ** CAPI3REF: Set A Busy Timeout |
| 1921 | ** |
| 1922 | ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps |
| 1923 | ** for a specified amount of time when a table is locked. ^The handler |
| 1924 | ** will sleep multiple times until at least "ms" milliseconds of sleeping |
| 1925 | ** have accumulated. ^After at least "ms" milliseconds of sleeping, |
| 1926 | ** the handler returns 0 which causes [sqlite3_step()] to return |
| 1927 | ** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]. |
| 1928 | ** |
| 1929 | ** ^Calling this routine with an argument less than or equal to zero |
| 1930 | ** turns off all busy handlers. |
| 1931 | ** |
| 1932 | ** ^(There can only be a single busy handler for a particular |
| 1933 | ** [database connection] any any given moment. If another busy handler |
| 1934 | ** was defined (using [sqlite3_busy_handler()]) prior to calling |
| 1935 | ** this routine, that other busy handler is cleared.)^ |
| 1936 | */ |
| 1937 | SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms); |
| 1938 | |
| 1939 | /* |
| 1940 | ** CAPI3REF: Convenience Routines For Running Queries |
| 1941 | ** |
| 1942 | ** This is a legacy interface that is preserved for backwards compatibility. |
| 1943 | ** Use of this interface is not recommended. |
| 1944 | ** |
| 1945 | ** Definition: A <b>result table</b> is memory data structure created by the |
| 1946 | ** [sqlite3_get_table()] interface. A result table records the |
| 1947 | ** complete query results from one or more queries. |
| 1948 | ** |
| 1949 | ** The table conceptually has a number of rows and columns. But |
| 1950 | ** these numbers are not part of the result table itself. These |
| 1951 | ** numbers are obtained separately. Let N be the number of rows |
| 1952 | ** and M be the number of columns. |
| 1953 | ** |
| 1954 | ** A result table is an array of pointers to zero-terminated UTF-8 strings. |
| 1955 | ** There are (N+1)*M elements in the array. The first M pointers point |
| 1956 | ** to zero-terminated strings that contain the names of the columns. |
| 1957 | ** The remaining entries all point to query results. NULL values result |
| 1958 | ** in NULL pointers. All other values are in their UTF-8 zero-terminated |
| 1959 | ** string representation as returned by [sqlite3_column_text()]. |
| 1960 | ** |
| 1961 | ** A result table might consist of one or more memory allocations. |
| 1962 | ** It is not safe to pass a result table directly to [sqlite3_free()]. |
| 1963 | ** A result table should be deallocated using [sqlite3_free_table()]. |
| 1964 | ** |
| 1965 | ** ^(As an example of the result table format, suppose a query result |
| 1966 | ** is as follows: |
| 1967 | ** |
| 1968 | ** <blockquote><pre> |
| 1969 | ** Name | Age |
| 1970 | ** ----------------------- |
| 1971 | ** Alice | 43 |
| 1972 | ** Bob | 28 |
| 1973 | ** Cindy | 21 |
| 1974 | ** </pre></blockquote> |
| 1975 | ** |
| 1976 | ** There are two column (M==2) and three rows (N==3). Thus the |
| 1977 | ** result table has 8 entries. Suppose the result table is stored |
| 1978 | ** in an array names azResult. Then azResult holds this content: |
| 1979 | ** |
| 1980 | ** <blockquote><pre> |
| 1981 | ** azResult[0] = "Name"; |
| 1982 | ** azResult[1] = "Age"; |
| 1983 | ** azResult[2] = "Alice"; |
| 1984 | ** azResult[3] = "43"; |
| 1985 | ** azResult[4] = "Bob"; |
| 1986 | ** azResult[5] = "28"; |
| 1987 | ** azResult[6] = "Cindy"; |
| 1988 | ** azResult[7] = "21"; |
| 1989 | ** </pre></blockquote>)^ |
| 1990 | ** |
| 1991 | ** ^The sqlite3_get_table() function evaluates one or more |
| 1992 | ** semicolon-separated SQL statements in the zero-terminated UTF-8 |
| 1993 | ** string of its 2nd parameter and returns a result table to the |
| 1994 | ** pointer given in its 3rd parameter. |
| 1995 | ** |
| 1996 | ** After the application has finished with the result from sqlite3_get_table(), |
| 1997 | ** it must pass the result table pointer to sqlite3_free_table() in order to |
| 1998 | ** release the memory that was malloced. Because of the way the |
| 1999 | ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling |
| 2000 | ** function must not try to call [sqlite3_free()] directly. Only |
| 2001 | ** [sqlite3_free_table()] is able to release the memory properly and safely. |
| 2002 | ** |
| 2003 | ** The sqlite3_get_table() interface is implemented as a wrapper around |
| 2004 | ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access |
| 2005 | ** to any internal data structures of SQLite. It uses only the public |
| 2006 | ** interface defined here. As a consequence, errors that occur in the |
| 2007 | ** wrapper layer outside of the internal [sqlite3_exec()] call are not |
| 2008 | ** reflected in subsequent calls to [sqlite3_errcode()] or |
| 2009 | ** [sqlite3_errmsg()]. |
| 2010 | */ |
| 2011 | SQLITE_API int sqlite3_get_table( |
| 2012 | sqlite3 *db, /* An open database */ |
| 2013 | const char *zSql, /* SQL to be evaluated */ |
| 2014 | char ***pazResult, /* Results of the query */ |
| 2015 | int *pnRow, /* Number of result rows written here */ |
| 2016 | int *pnColumn, /* Number of result columns written here */ |
| 2017 | char **pzErrmsg /* Error msg written here */ |
| 2018 | ); |
| 2019 | SQLITE_API void sqlite3_free_table(char **result); |
| 2020 | |
| 2021 | /* |
| 2022 | ** CAPI3REF: Formatted String Printing Functions |
| 2023 | ** |
| 2024 | ** These routines are work-alikes of the "printf()" family of functions |
| 2025 | ** from the standard C library. |
| 2026 | ** |
| 2027 | ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their |
| 2028 | ** results into memory obtained from [sqlite3_malloc()]. |
| 2029 | ** The strings returned by these two routines should be |
| 2030 | ** released by [sqlite3_free()]. ^Both routines return a |
| 2031 | ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough |
| 2032 | ** memory to hold the resulting string. |
| 2033 | ** |
| 2034 | ** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from |
| 2035 | ** the standard C library. The result is written into the |
| 2036 | ** buffer supplied as the second parameter whose size is given by |
| 2037 | ** the first parameter. Note that the order of the |
| 2038 | ** first two parameters is reversed from snprintf().)^ This is an |
| 2039 | ** historical accident that cannot be fixed without breaking |
| 2040 | ** backwards compatibility. ^(Note also that sqlite3_snprintf() |
| 2041 | ** returns a pointer to its buffer instead of the number of |
| 2042 | ** characters actually written into the buffer.)^ We admit that |
| 2043 | ** the number of characters written would be a more useful return |
| 2044 | ** value but we cannot change the implementation of sqlite3_snprintf() |
| 2045 | ** now without breaking compatibility. |
| 2046 | ** |
| 2047 | ** ^As long as the buffer size is greater than zero, sqlite3_snprintf() |
| 2048 | ** guarantees that the buffer is always zero-terminated. ^The first |
| 2049 | ** parameter "n" is the total size of the buffer, including space for |
| 2050 | ** the zero terminator. So the longest string that can be completely |
| 2051 | ** written will be n-1 characters. |
| 2052 | ** |
| 2053 | ** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf(). |
| 2054 | ** |
| 2055 | ** These routines all implement some additional formatting |
| 2056 | ** options that are useful for constructing SQL statements. |
| 2057 | ** All of the usual printf() formatting options apply. In addition, there |
| 2058 | ** is are "%q", "%Q", and "%z" options. |
| 2059 | ** |
| 2060 | ** ^(The %q option works like %s in that it substitutes a nul-terminated |
| 2061 | ** string from the argument list. But %q also doubles every '\'' character. |
| 2062 | ** %q is designed for use inside a string literal.)^ By doubling each '\'' |
| 2063 | ** character it escapes that character and allows it to be inserted into |
| 2064 | ** the string. |
| 2065 | ** |
| 2066 | ** For example, assume the string variable zText contains text as follows: |
| 2067 | ** |
| 2068 | ** <blockquote><pre> |
| 2069 | ** char *zText = "It's a happy day!"; |
| 2070 | ** </pre></blockquote> |
| 2071 | ** |
| 2072 | ** One can use this text in an SQL statement as follows: |
| 2073 | ** |
| 2074 | ** <blockquote><pre> |
| 2075 | ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText); |
| 2076 | ** sqlite3_exec(db, zSQL, 0, 0, 0); |
| 2077 | ** sqlite3_free(zSQL); |
| 2078 | ** </pre></blockquote> |
| 2079 | ** |
| 2080 | ** Because the %q format string is used, the '\'' character in zText |
| 2081 | ** is escaped and the SQL generated is as follows: |
| 2082 | ** |
| 2083 | ** <blockquote><pre> |
| 2084 | ** INSERT INTO table1 VALUES('It''s a happy day!') |
| 2085 | ** </pre></blockquote> |
| 2086 | ** |
| 2087 | ** This is correct. Had we used %s instead of %q, the generated SQL |
| 2088 | ** would have looked like this: |
| 2089 | ** |
| 2090 | ** <blockquote><pre> |
| 2091 | ** INSERT INTO table1 VALUES('It's a happy day!'); |
| 2092 | ** </pre></blockquote> |
| 2093 | ** |
| 2094 | ** This second example is an SQL syntax error. As a general rule you should |
| 2095 | ** always use %q instead of %s when inserting text into a string literal. |
| 2096 | ** |
| 2097 | ** ^(The %Q option works like %q except it also adds single quotes around |
| 2098 | ** the outside of the total string. Additionally, if the parameter in the |
| 2099 | ** argument list is a NULL pointer, %Q substitutes the text "NULL" (without |
| 2100 | ** single quotes).)^ So, for example, one could say: |
| 2101 | ** |
| 2102 | ** <blockquote><pre> |
| 2103 | ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText); |
| 2104 | ** sqlite3_exec(db, zSQL, 0, 0, 0); |
| 2105 | ** sqlite3_free(zSQL); |
| 2106 | ** </pre></blockquote> |
| 2107 | ** |
| 2108 | ** The code above will render a correct SQL statement in the zSQL |
| 2109 | ** variable even if the zText variable is a NULL pointer. |
| 2110 | ** |
| 2111 | ** ^(The "%z" formatting option works like "%s" but with the |
| 2112 | ** addition that after the string has been read and copied into |
| 2113 | ** the result, [sqlite3_free()] is called on the input string.)^ |
| 2114 | */ |
| 2115 | SQLITE_API char *sqlite3_mprintf(const char*,...); |
| 2116 | SQLITE_API char *sqlite3_vmprintf(const char*, va_list); |
| 2117 | SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...); |
| 2118 | SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list); |
| 2119 | |
| 2120 | /* |
| 2121 | ** CAPI3REF: Memory Allocation Subsystem |
| 2122 | ** |
| 2123 | ** The SQLite core uses these three routines for all of its own |
| 2124 | ** internal memory allocation needs. "Core" in the previous sentence |
| 2125 | ** does not include operating-system specific VFS implementation. The |
| 2126 | ** Windows VFS uses native malloc() and free() for some operations. |
| 2127 | ** |
| 2128 | ** ^The sqlite3_malloc() routine returns a pointer to a block |
| 2129 | ** of memory at least N bytes in length, where N is the parameter. |
| 2130 | ** ^If sqlite3_malloc() is unable to obtain sufficient free |
| 2131 | ** memory, it returns a NULL pointer. ^If the parameter N to |
| 2132 | ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns |
| 2133 | ** a NULL pointer. |
| 2134 | ** |
| 2135 | ** ^Calling sqlite3_free() with a pointer previously returned |
| 2136 | ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so |
| 2137 | ** that it might be reused. ^The sqlite3_free() routine is |
| 2138 | ** a no-op if is called with a NULL pointer. Passing a NULL pointer |
| 2139 | ** to sqlite3_free() is harmless. After being freed, memory |
| 2140 | ** should neither be read nor written. Even reading previously freed |
| 2141 | ** memory might result in a segmentation fault or other severe error. |
| 2142 | ** Memory corruption, a segmentation fault, or other severe error |
| 2143 | ** might result if sqlite3_free() is called with a non-NULL pointer that |
| 2144 | ** was not obtained from sqlite3_malloc() or sqlite3_realloc(). |
| 2145 | ** |
| 2146 | ** ^(The sqlite3_realloc() interface attempts to resize a |
| 2147 | ** prior memory allocation to be at least N bytes, where N is the |
| 2148 | ** second parameter. The memory allocation to be resized is the first |
| 2149 | ** parameter.)^ ^ If the first parameter to sqlite3_realloc() |
| 2150 | ** is a NULL pointer then its behavior is identical to calling |
| 2151 | ** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc(). |
| 2152 | ** ^If the second parameter to sqlite3_realloc() is zero or |
| 2153 | ** negative then the behavior is exactly the same as calling |
| 2154 | ** sqlite3_free(P) where P is the first parameter to sqlite3_realloc(). |
| 2155 | ** ^sqlite3_realloc() returns a pointer to a memory allocation |
| 2156 | ** of at least N bytes in size or NULL if sufficient memory is unavailable. |
| 2157 | ** ^If M is the size of the prior allocation, then min(N,M) bytes |
| 2158 | ** of the prior allocation are copied into the beginning of buffer returned |
| 2159 | ** by sqlite3_realloc() and the prior allocation is freed. |
| 2160 | ** ^If sqlite3_realloc() returns NULL, then the prior allocation |
| 2161 | ** is not freed. |
| 2162 | ** |
| 2163 | ** ^The memory returned by sqlite3_malloc() and sqlite3_realloc() |
| 2164 | ** is always aligned to at least an 8 byte boundary, or to a |
| 2165 | ** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time |
| 2166 | ** option is used. |
| 2167 | ** |
| 2168 | ** In SQLite version 3.5.0 and 3.5.1, it was possible to define |
| 2169 | ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in |
| 2170 | ** implementation of these routines to be omitted. That capability |
| 2171 | ** is no longer provided. Only built-in memory allocators can be used. |
| 2172 | ** |
| 2173 | ** Prior to SQLite version 3.7.10, the Windows OS interface layer called |
| 2174 | ** the system malloc() and free() directly when converting |
| 2175 | ** filenames between the UTF-8 encoding used by SQLite |
| 2176 | ** and whatever filename encoding is used by the particular Windows |
| 2177 | ** installation. Memory allocation errors were detected, but |
| 2178 | ** they were reported back as [SQLITE_CANTOPEN] or |
| 2179 | ** [SQLITE_IOERR] rather than [SQLITE_NOMEM]. |
| 2180 | ** |
| 2181 | ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] |
| 2182 | ** must be either NULL or else pointers obtained from a prior |
| 2183 | ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have |
| 2184 | ** not yet been released. |
| 2185 | ** |
| 2186 | ** The application must not read or write any part of |
| 2187 | ** a block of memory after it has been released using |
| 2188 | ** [sqlite3_free()] or [sqlite3_realloc()]. |
| 2189 | */ |
| 2190 | SQLITE_API void *sqlite3_malloc(int); |
| 2191 | SQLITE_API void *sqlite3_realloc(void*, int); |
| 2192 | SQLITE_API void sqlite3_free(void*); |
| 2193 | |
| 2194 | /* |
| 2195 | ** CAPI3REF: Memory Allocator Statistics |
| 2196 | ** |
| 2197 | ** SQLite provides these two interfaces for reporting on the status |
| 2198 | ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] |
| 2199 | ** routines, which form the built-in memory allocation subsystem. |
| 2200 | ** |
| 2201 | ** ^The [sqlite3_memory_used()] routine returns the number of bytes |
| 2202 | ** of memory currently outstanding (malloced but not freed). |
| 2203 | ** ^The [sqlite3_memory_highwater()] routine returns the maximum |
| 2204 | ** value of [sqlite3_memory_used()] since the high-water mark |
| 2205 | ** was last reset. ^The values returned by [sqlite3_memory_used()] and |
| 2206 | ** [sqlite3_memory_highwater()] include any overhead |
| 2207 | ** added by SQLite in its implementation of [sqlite3_malloc()], |
| 2208 | ** but not overhead added by the any underlying system library |
| 2209 | ** routines that [sqlite3_malloc()] may call. |
| 2210 | ** |
| 2211 | ** ^The memory high-water mark is reset to the current value of |
| 2212 | ** [sqlite3_memory_used()] if and only if the parameter to |
| 2213 | ** [sqlite3_memory_highwater()] is true. ^The value returned |
| 2214 | ** by [sqlite3_memory_highwater(1)] is the high-water mark |
| 2215 | ** prior to the reset. |
| 2216 | */ |
| 2217 | SQLITE_API sqlite3_int64 sqlite3_memory_used(void); |
| 2218 | SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag); |
| 2219 | |
| 2220 | /* |
| 2221 | ** CAPI3REF: Pseudo-Random Number Generator |
| 2222 | ** |
| 2223 | ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to |
| 2224 | ** select random [ROWID | ROWIDs] when inserting new records into a table that |
| 2225 | ** already uses the largest possible [ROWID]. The PRNG is also used for |
| 2226 | ** the build-in random() and randomblob() SQL functions. This interface allows |
| 2227 | ** applications to access the same PRNG for other purposes. |
| 2228 | ** |
| 2229 | ** ^A call to this routine stores N bytes of randomness into buffer P. |
| 2230 | ** |
| 2231 | ** ^The first time this routine is invoked (either internally or by |
| 2232 | ** the application) the PRNG is seeded using randomness obtained |
| 2233 | ** from the xRandomness method of the default [sqlite3_vfs] object. |
| 2234 | ** ^On all subsequent invocations, the pseudo-randomness is generated |
| 2235 | ** internally and without recourse to the [sqlite3_vfs] xRandomness |
| 2236 | ** method. |
| 2237 | */ |
| 2238 | SQLITE_API void sqlite3_randomness(int N, void *P); |
| 2239 | |
| 2240 | /* |
| 2241 | ** CAPI3REF: Compile-Time Authorization Callbacks |
| 2242 | ** |
| 2243 | ** ^This routine registers an authorizer callback with a particular |
| 2244 | ** [database connection], supplied in the first argument. |
| 2245 | ** ^The authorizer callback is invoked as SQL statements are being compiled |
| 2246 | ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], |
| 2247 | ** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. ^At various |
| 2248 | ** points during the compilation process, as logic is being created |
| 2249 | ** to perform various actions, the authorizer callback is invoked to |
| 2250 | ** see if those actions are allowed. ^The authorizer callback should |
| 2251 | ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the |
| 2252 | ** specific action but allow the SQL statement to continue to be |
| 2253 | ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be |
| 2254 | ** rejected with an error. ^If the authorizer callback returns |
| 2255 | ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] |
| 2256 | ** then the [sqlite3_prepare_v2()] or equivalent call that triggered |
| 2257 | ** the authorizer will fail with an error message. |
| 2258 | ** |
| 2259 | ** When the callback returns [SQLITE_OK], that means the operation |
| 2260 | ** requested is ok. ^When the callback returns [SQLITE_DENY], the |
| 2261 | ** [sqlite3_prepare_v2()] or equivalent call that triggered the |
| 2262 | ** authorizer will fail with an error message explaining that |
| 2263 | ** access is denied. |
| 2264 | ** |
| 2265 | ** ^The first parameter to the authorizer callback is a copy of the third |
| 2266 | ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter |
| 2267 | ** to the callback is an integer [SQLITE_COPY | action code] that specifies |
| 2268 | ** the particular action to be authorized. ^The third through sixth parameters |
| 2269 | ** to the callback are zero-terminated strings that contain additional |
| 2270 | ** details about the action to be authorized. |
| 2271 | ** |
| 2272 | ** ^If the action code is [SQLITE_READ] |
| 2273 | ** and the callback returns [SQLITE_IGNORE] then the |
| 2274 | ** [prepared statement] statement is constructed to substitute |
| 2275 | ** a NULL value in place of the table column that would have |
| 2276 | ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] |
| 2277 | ** return can be used to deny an untrusted user access to individual |
| 2278 | ** columns of a table. |
| 2279 | ** ^If the action code is [SQLITE_DELETE] and the callback returns |
| 2280 | ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the |
| 2281 | ** [truncate optimization] is disabled and all rows are deleted individually. |
| 2282 | ** |
| 2283 | ** An authorizer is used when [sqlite3_prepare | preparing] |
| 2284 | ** SQL statements from an untrusted source, to ensure that the SQL statements |
| 2285 | ** do not try to access data they are not allowed to see, or that they do not |
| 2286 | ** try to execute malicious statements that damage the database. For |
| 2287 | ** example, an application may allow a user to enter arbitrary |
| 2288 | ** SQL queries for evaluation by a database. But the application does |
| 2289 | ** not want the user to be able to make arbitrary changes to the |
| 2290 | ** database. An authorizer could then be put in place while the |
| 2291 | ** user-entered SQL is being [sqlite3_prepare | prepared] that |
| 2292 | ** disallows everything except [SELECT] statements. |
| 2293 | ** |
| 2294 | ** Applications that need to process SQL from untrusted sources |
| 2295 | ** might also consider lowering resource limits using [sqlite3_limit()] |
| 2296 | ** and limiting database size using the [max_page_count] [PRAGMA] |
| 2297 | ** in addition to using an authorizer. |
| 2298 | ** |
| 2299 | ** ^(Only a single authorizer can be in place on a database connection |
| 2300 | ** at a time. Each call to sqlite3_set_authorizer overrides the |
| 2301 | ** previous call.)^ ^Disable the authorizer by installing a NULL callback. |
| 2302 | ** The authorizer is disabled by default. |
| 2303 | ** |
| 2304 | ** The authorizer callback must not do anything that will modify |
| 2305 | ** the database connection that invoked the authorizer callback. |
| 2306 | ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their |
| 2307 | ** database connections for the meaning of "modify" in this paragraph. |
| 2308 | ** |
| 2309 | ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the |
| 2310 | ** statement might be re-prepared during [sqlite3_step()] due to a |
| 2311 | ** schema change. Hence, the application should ensure that the |
| 2312 | ** correct authorizer callback remains in place during the [sqlite3_step()]. |
| 2313 | ** |
| 2314 | ** ^Note that the authorizer callback is invoked only during |
| 2315 | ** [sqlite3_prepare()] or its variants. Authorization is not |
| 2316 | ** performed during statement evaluation in [sqlite3_step()], unless |
| 2317 | ** as stated in the previous paragraph, sqlite3_step() invokes |
| 2318 | ** sqlite3_prepare_v2() to reprepare a statement after a schema change. |
| 2319 | */ |
| 2320 | SQLITE_API int sqlite3_set_authorizer( |
| 2321 | sqlite3*, |
| 2322 | int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), |
| 2323 | void *pUserData |
| 2324 | ); |
| 2325 | |
| 2326 | /* |
| 2327 | ** CAPI3REF: Authorizer Return Codes |
| 2328 | ** |
| 2329 | ** The [sqlite3_set_authorizer | authorizer callback function] must |
| 2330 | ** return either [SQLITE_OK] or one of these two constants in order |
| 2331 | ** to signal SQLite whether or not the action is permitted. See the |
| 2332 | ** [sqlite3_set_authorizer | authorizer documentation] for additional |
| 2333 | ** information. |
| 2334 | ** |
| 2335 | ** Note that SQLITE_IGNORE is also used as a [SQLITE_ROLLBACK | return code] |
| 2336 | ** from the [sqlite3_vtab_on_conflict()] interface. |
| 2337 | */ |
| 2338 | #define SQLITE_DENY 1 /* Abort the SQL statement with an error */ |
| 2339 | #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ |
| 2340 | |
| 2341 | /* |
| 2342 | ** CAPI3REF: Authorizer Action Codes |
| 2343 | ** |
| 2344 | ** The [sqlite3_set_authorizer()] interface registers a callback function |
| 2345 | ** that is invoked to authorize certain SQL statement actions. The |
| 2346 | ** second parameter to the callback is an integer code that specifies |
| 2347 | ** what action is being authorized. These are the integer action codes that |
| 2348 | ** the authorizer callback may be passed. |
| 2349 | ** |
| 2350 | ** These action code values signify what kind of operation is to be |
| 2351 | ** authorized. The 3rd and 4th parameters to the authorization |
| 2352 | ** callback function will be parameters or NULL depending on which of these |
| 2353 | ** codes is used as the second parameter. ^(The 5th parameter to the |
| 2354 | ** authorizer callback is the name of the database ("main", "temp", |
| 2355 | ** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback |
| 2356 | ** is the name of the inner-most trigger or view that is responsible for |
| 2357 | ** the access attempt or NULL if this access attempt is directly from |
| 2358 | ** top-level SQL code. |
| 2359 | */ |
| 2360 | /******************************************* 3rd ************ 4th ***********/ |
| 2361 | #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ |
| 2362 | #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ |
| 2363 | #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ |
| 2364 | #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ |
| 2365 | #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ |
| 2366 | #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ |
| 2367 | #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ |
| 2368 | #define SQLITE_CREATE_VIEW 8 /* View Name NULL */ |
| 2369 | #define SQLITE_DELETE 9 /* Table Name NULL */ |
| 2370 | #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ |
| 2371 | #define SQLITE_DROP_TABLE 11 /* Table Name NULL */ |
| 2372 | #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ |
| 2373 | #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ |
| 2374 | #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ |
| 2375 | #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ |
| 2376 | #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ |
| 2377 | #define SQLITE_DROP_VIEW 17 /* View Name NULL */ |
| 2378 | #define SQLITE_INSERT 18 /* Table Name NULL */ |
| 2379 | #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ |
| 2380 | #define SQLITE_READ 20 /* Table Name Column Name */ |
| 2381 | #define SQLITE_SELECT 21 /* NULL NULL */ |
| 2382 | #define SQLITE_TRANSACTION 22 /* Operation NULL */ |
| 2383 | #define SQLITE_UPDATE 23 /* Table Name Column Name */ |
| 2384 | #define SQLITE_ATTACH 24 /* Filename NULL */ |
| 2385 | #define SQLITE_DETACH 25 /* Database Name NULL */ |
| 2386 | #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ |
| 2387 | #define SQLITE_REINDEX 27 /* Index Name NULL */ |
| 2388 | #define SQLITE_ANALYZE 28 /* Table Name NULL */ |
| 2389 | #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ |
| 2390 | #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ |
| 2391 | #define SQLITE_FUNCTION 31 /* NULL Function Name */ |
| 2392 | #define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */ |
| 2393 | #define SQLITE_COPY 0 /* No longer used */ |
| 2394 | |
| 2395 | /* |
| 2396 | ** CAPI3REF: Tracing And Profiling Functions |
| 2397 | ** |
| 2398 | ** These routines register callback functions that can be used for |
| 2399 | ** tracing and profiling the execution of SQL statements. |
| 2400 | ** |
| 2401 | ** ^The callback function registered by sqlite3_trace() is invoked at |
| 2402 | ** various times when an SQL statement is being run by [sqlite3_step()]. |
| 2403 | ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the |
| 2404 | ** SQL statement text as the statement first begins executing. |
| 2405 | ** ^(Additional sqlite3_trace() callbacks might occur |
| 2406 | ** as each triggered subprogram is entered. The callbacks for triggers |
| 2407 | ** contain a UTF-8 SQL comment that identifies the trigger.)^ |
| 2408 | ** |
| 2409 | ** ^The callback function registered by sqlite3_profile() is invoked |
| 2410 | ** as each SQL statement finishes. ^The profile callback contains |
| 2411 | ** the original statement text and an estimate of wall-clock time |
| 2412 | ** of how long that statement took to run. ^The profile callback |
| 2413 | ** time is in units of nanoseconds, however the current implementation |
| 2414 | ** is only capable of millisecond resolution so the six least significant |
| 2415 | ** digits in the time are meaningless. Future versions of SQLite |
| 2416 | ** might provide greater resolution on the profiler callback. The |
| 2417 | ** sqlite3_profile() function is considered experimental and is |
| 2418 | ** subject to change in future versions of SQLite. |
| 2419 | */ |
| 2420 | SQLITE_API void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*); |
| 2421 | SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*, |
| 2422 | void(*xProfile)(void*,const char*,sqlite3_uint64), void*); |
| 2423 | |
| 2424 | /* |
| 2425 | ** CAPI3REF: Query Progress Callbacks |
| 2426 | ** |
| 2427 | ** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback |
| 2428 | ** function X to be invoked periodically during long running calls to |
| 2429 | ** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for |
| 2430 | ** database connection D. An example use for this |
| 2431 | ** interface is to keep a GUI updated during a large query. |
| 2432 | ** |
| 2433 | ** ^The parameter P is passed through as the only parameter to the |
| 2434 | ** callback function X. ^The parameter N is the number of |
| 2435 | ** [virtual machine instructions] that are evaluated between successive |
| 2436 | ** invocations of the callback X. |
| 2437 | ** |
| 2438 | ** ^Only a single progress handler may be defined at one time per |
| 2439 | ** [database connection]; setting a new progress handler cancels the |
| 2440 | ** old one. ^Setting parameter X to NULL disables the progress handler. |
| 2441 | ** ^The progress handler is also disabled by setting N to a value less |
| 2442 | ** than 1. |
| 2443 | ** |
| 2444 | ** ^If the progress callback returns non-zero, the operation is |
| 2445 | ** interrupted. This feature can be used to implement a |
| 2446 | ** "Cancel" button on a GUI progress dialog box. |
| 2447 | ** |
| 2448 | ** The progress handler callback must not do anything that will modify |
| 2449 | ** the database connection that invoked the progress handler. |
| 2450 | ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their |
| 2451 | ** database connections for the meaning of "modify" in this paragraph. |
| 2452 | ** |
| 2453 | */ |
| 2454 | SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); |
| 2455 | |
| 2456 | /* |
| 2457 | ** CAPI3REF: Opening A New Database Connection |
| 2458 | ** |
| 2459 | ** ^These routines open an SQLite database file as specified by the |
| 2460 | ** filename argument. ^The filename argument is interpreted as UTF-8 for |
| 2461 | ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte |
| 2462 | ** order for sqlite3_open16(). ^(A [database connection] handle is usually |
| 2463 | ** returned in *ppDb, even if an error occurs. The only exception is that |
| 2464 | ** if SQLite is unable to allocate memory to hold the [sqlite3] object, |
| 2465 | ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3] |
| 2466 | ** object.)^ ^(If the database is opened (and/or created) successfully, then |
| 2467 | ** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The |
| 2468 | ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain |
| 2469 | ** an English language description of the error following a failure of any |
| 2470 | ** of the sqlite3_open() routines. |
| 2471 | ** |
| 2472 | ** ^The default encoding for the database will be UTF-8 if |
| 2473 | ** sqlite3_open() or sqlite3_open_v2() is called and |
| 2474 | ** UTF-16 in the native byte order if sqlite3_open16() is used. |
| 2475 | ** |
| 2476 | ** Whether or not an error occurs when it is opened, resources |
| 2477 | ** associated with the [database connection] handle should be released by |
| 2478 | ** passing it to [sqlite3_close()] when it is no longer required. |
| 2479 | ** |
| 2480 | ** The sqlite3_open_v2() interface works like sqlite3_open() |
| 2481 | ** except that it accepts two additional parameters for additional control |
| 2482 | ** over the new database connection. ^(The flags parameter to |
| 2483 | ** sqlite3_open_v2() can take one of |
| 2484 | ** the following three values, optionally combined with the |
| 2485 | ** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE], |
| 2486 | ** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^ |
| 2487 | ** |
| 2488 | ** <dl> |
| 2489 | ** ^(<dt>[SQLITE_OPEN_READONLY]</dt> |
| 2490 | ** <dd>The database is opened in read-only mode. If the database does not |
| 2491 | ** already exist, an error is returned.</dd>)^ |
| 2492 | ** |
| 2493 | ** ^(<dt>[SQLITE_OPEN_READWRITE]</dt> |
| 2494 | ** <dd>The database is opened for reading and writing if possible, or reading |
| 2495 | ** only if the file is write protected by the operating system. In either |
| 2496 | ** case the database must already exist, otherwise an error is returned.</dd>)^ |
| 2497 | ** |
| 2498 | ** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt> |
| 2499 | ** <dd>The database is opened for reading and writing, and is created if |
| 2500 | ** it does not already exist. This is the behavior that is always used for |
| 2501 | ** sqlite3_open() and sqlite3_open16().</dd>)^ |
| 2502 | ** </dl> |
| 2503 | ** |
| 2504 | ** If the 3rd parameter to sqlite3_open_v2() is not one of the |
| 2505 | ** combinations shown above optionally combined with other |
| 2506 | ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits] |
| 2507 | ** then the behavior is undefined. |
| 2508 | ** |
| 2509 | ** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection |
| 2510 | ** opens in the multi-thread [threading mode] as long as the single-thread |
| 2511 | ** mode has not been set at compile-time or start-time. ^If the |
| 2512 | ** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens |
| 2513 | ** in the serialized [threading mode] unless single-thread was |
| 2514 | ** previously selected at compile-time or start-time. |
| 2515 | ** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be |
| 2516 | ** eligible to use [shared cache mode], regardless of whether or not shared |
| 2517 | ** cache is enabled using [sqlite3_enable_shared_cache()]. ^The |
| 2518 | ** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not |
| 2519 | ** participate in [shared cache mode] even if it is enabled. |
| 2520 | ** |
| 2521 | ** ^The fourth parameter to sqlite3_open_v2() is the name of the |
| 2522 | ** [sqlite3_vfs] object that defines the operating system interface that |
| 2523 | ** the new database connection should use. ^If the fourth parameter is |
| 2524 | ** a NULL pointer then the default [sqlite3_vfs] object is used. |
| 2525 | ** |
| 2526 | ** ^If the filename is ":memory:", then a private, temporary in-memory database |
| 2527 | ** is created for the connection. ^This in-memory database will vanish when |
| 2528 | ** the database connection is closed. Future versions of SQLite might |
| 2529 | ** make use of additional special filenames that begin with the ":" character. |
| 2530 | ** It is recommended that when a database filename actually does begin with |
| 2531 | ** a ":" character you should prefix the filename with a pathname such as |
| 2532 | ** "./" to avoid ambiguity. |
| 2533 | ** |
| 2534 | ** ^If the filename is an empty string, then a private, temporary |
| 2535 | ** on-disk database will be created. ^This private database will be |
| 2536 | ** automatically deleted as soon as the database connection is closed. |
| 2537 | ** |
| 2538 | ** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3> |
| 2539 | ** |
| 2540 | ** ^If [URI filename] interpretation is enabled, and the filename argument |
| 2541 | ** begins with "file:", then the filename is interpreted as a URI. ^URI |
| 2542 | ** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is |
| 2543 | ** set in the fourth argument to sqlite3_open_v2(), or if it has |
| 2544 | ** been enabled globally using the [SQLITE_CONFIG_URI] option with the |
| 2545 | ** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option. |
| 2546 | ** As of SQLite version 3.7.7, URI filename interpretation is turned off |
| 2547 | ** by default, but future releases of SQLite might enable URI filename |
| 2548 | ** interpretation by default. See "[URI filenames]" for additional |
| 2549 | ** information. |
| 2550 | ** |
| 2551 | ** URI filenames are parsed according to RFC 3986. ^If the URI contains an |
| 2552 | ** authority, then it must be either an empty string or the string |
| 2553 | ** "localhost". ^If the authority is not an empty string or "localhost", an |
| 2554 | ** error is returned to the caller. ^The fragment component of a URI, if |
| 2555 | ** present, is ignored. |
| 2556 | ** |
| 2557 | ** ^SQLite uses the path component of the URI as the name of the disk file |
| 2558 | ** which contains the database. ^If the path begins with a '/' character, |
| 2559 | ** then it is interpreted as an absolute path. ^If the path does not begin |
| 2560 | ** with a '/' (meaning that the authority section is omitted from the URI) |
| 2561 | ** then the path is interpreted as a relative path. |
| 2562 | ** ^On windows, the first component of an absolute path |
| 2563 | ** is a drive specification (e.g. "C:"). |
| 2564 | ** |
| 2565 | ** [[core URI query parameters]] |
| 2566 | ** The query component of a URI may contain parameters that are interpreted |
| 2567 | ** either by SQLite itself, or by a [VFS | custom VFS implementation]. |
| 2568 | ** SQLite interprets the following three query parameters: |
| 2569 | ** |
| 2570 | ** <ul> |
| 2571 | ** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of |
| 2572 | ** a VFS object that provides the operating system interface that should |
| 2573 | ** be used to access the database file on disk. ^If this option is set to |
| 2574 | ** an empty string the default VFS object is used. ^Specifying an unknown |
| 2575 | ** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is |
| 2576 | ** present, then the VFS specified by the option takes precedence over |
| 2577 | ** the value passed as the fourth parameter to sqlite3_open_v2(). |
| 2578 | ** |
| 2579 | ** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw", |
| 2580 | ** "rwc", or "memory". Attempting to set it to any other value is |
| 2581 | ** an error)^. |
| 2582 | ** ^If "ro" is specified, then the database is opened for read-only |
| 2583 | ** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the |
| 2584 | ** third argument to sqlite3_prepare_v2(). ^If the mode option is set to |
| 2585 | ** "rw", then the database is opened for read-write (but not create) |
| 2586 | ** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had |
| 2587 | ** been set. ^Value "rwc" is equivalent to setting both |
| 2588 | ** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is |
| 2589 | ** set to "memory" then a pure [in-memory database] that never reads |
| 2590 | ** or writes from disk is used. ^It is an error to specify a value for |
| 2591 | ** the mode parameter that is less restrictive than that specified by |
| 2592 | ** the flags passed in the third parameter to sqlite3_open_v2(). |
| 2593 | ** |
| 2594 | ** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or |
| 2595 | ** "private". ^Setting it to "shared" is equivalent to setting the |
| 2596 | ** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to |
| 2597 | ** sqlite3_open_v2(). ^Setting the cache parameter to "private" is |
| 2598 | ** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit. |
| 2599 | ** ^If sqlite3_open_v2() is used and the "cache" parameter is present in |
| 2600 | ** a URI filename, its value overrides any behaviour requested by setting |
| 2601 | ** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag. |
| 2602 | ** </ul> |
| 2603 | ** |
| 2604 | ** ^Specifying an unknown parameter in the query component of a URI is not an |
| 2605 | ** error. Future versions of SQLite might understand additional query |
| 2606 | ** parameters. See "[query parameters with special meaning to SQLite]" for |
| 2607 | ** additional information. |
| 2608 | ** |
| 2609 | ** [[URI filename examples]] <h3>URI filename examples</h3> |
| 2610 | ** |
| 2611 | ** <table border="1" align=center cellpadding=5> |
| 2612 | ** <tr><th> URI filenames <th> Results |
| 2613 | ** <tr><td> file:data.db <td> |
| 2614 | ** Open the file "data.db" in the current directory. |
| 2615 | ** <tr><td> file:/home/fred/data.db<br> |
| 2616 | ** file:///home/fred/data.db <br> |
| 2617 | ** file://localhost/home/fred/data.db <br> <td> |
| 2618 | ** Open the database file "/home/fred/data.db". |
| 2619 | ** <tr><td> file://darkstar/home/fred/data.db <td> |
| 2620 | ** An error. "darkstar" is not a recognized authority. |
| 2621 | ** <tr><td style="white-space:nowrap"> |
| 2622 | ** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db |
| 2623 | ** <td> Windows only: Open the file "data.db" on fred's desktop on drive |
| 2624 | ** C:. Note that the %20 escaping in this example is not strictly |
| 2625 | ** necessary - space characters can be used literally |
| 2626 | ** in URI filenames. |
| 2627 | ** <tr><td> file:data.db?mode=ro&cache=private <td> |
| 2628 | ** Open file "data.db" in the current directory for read-only access. |
| 2629 | ** Regardless of whether or not shared-cache mode is enabled by |
| 2630 | ** default, use a private cache. |
| 2631 | ** <tr><td> file:/home/fred/data.db?vfs=unix-nolock <td> |
| 2632 | ** Open file "/home/fred/data.db". Use the special VFS "unix-nolock". |
| 2633 | ** <tr><td> file:data.db?mode=readonly <td> |
| 2634 | ** An error. "readonly" is not a valid option for the "mode" parameter. |
| 2635 | ** </table> |
| 2636 | ** |
| 2637 | ** ^URI hexadecimal escape sequences (%HH) are supported within the path and |
| 2638 | ** query components of a URI. A hexadecimal escape sequence consists of a |
| 2639 | ** percent sign - "%" - followed by exactly two hexadecimal digits |
| 2640 | ** specifying an octet value. ^Before the path or query components of a |
| 2641 | ** URI filename are interpreted, they are encoded using UTF-8 and all |
| 2642 | ** hexadecimal escape sequences replaced by a single byte containing the |
| 2643 | ** corresponding octet. If this process generates an invalid UTF-8 encoding, |
| 2644 | ** the results are undefined. |
| 2645 | ** |
| 2646 | ** <b>Note to Windows users:</b> The encoding used for the filename argument |
| 2647 | ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever |
| 2648 | ** codepage is currently defined. Filenames containing international |
| 2649 | ** characters must be converted to UTF-8 prior to passing them into |
| 2650 | ** sqlite3_open() or sqlite3_open_v2(). |
| 2651 | */ |
| 2652 | SQLITE_API int sqlite3_open( |
| 2653 | const char *filename, /* Database filename (UTF-8) */ |
| 2654 | sqlite3 **ppDb /* OUT: SQLite db handle */ |
| 2655 | ); |
| 2656 | SQLITE_API int sqlite3_open16( |
| 2657 | const void *filename, /* Database filename (UTF-16) */ |
| 2658 | sqlite3 **ppDb /* OUT: SQLite db handle */ |
| 2659 | ); |
| 2660 | SQLITE_API int sqlite3_open_v2( |
| 2661 | const char *filename, /* Database filename (UTF-8) */ |
| 2662 | sqlite3 **ppDb, /* OUT: SQLite db handle */ |
| 2663 | int flags, /* Flags */ |
| 2664 | const char *zVfs /* Name of VFS module to use */ |
| 2665 | ); |
| 2666 | |
| 2667 | /* |
| 2668 | ** CAPI3REF: Obtain Values For URI Parameters |
| 2669 | ** |
| 2670 | ** These are utility routines, useful to VFS implementations, that check |
| 2671 | ** to see if a database file was a URI that contained a specific query |
| 2672 | ** parameter, and if so obtains the value of that query parameter. |
| 2673 | ** |
| 2674 | ** If F is the database filename pointer passed into the xOpen() method of |
| 2675 | ** a VFS implementation when the flags parameter to xOpen() has one or |
| 2676 | ** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and |
| 2677 | ** P is the name of the query parameter, then |
| 2678 | ** sqlite3_uri_parameter(F,P) returns the value of the P |
| 2679 | ** parameter if it exists or a NULL pointer if P does not appear as a |
| 2680 | ** query parameter on F. If P is a query parameter of F |
| 2681 | ** has no explicit value, then sqlite3_uri_parameter(F,P) returns |
| 2682 | ** a pointer to an empty string. |
| 2683 | ** |
| 2684 | ** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean |
| 2685 | ** parameter and returns true (1) or false (0) according to the value |
| 2686 | ** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the |
| 2687 | ** value of query parameter P is one of "yes", "true", or "on" in any |
| 2688 | ** case or if the value begins with a non-zero number. The |
| 2689 | ** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of |
| 2690 | ** query parameter P is one of "no", "false", or "off" in any case or |
| 2691 | ** if the value begins with a numeric zero. If P is not a query |
| 2692 | ** parameter on F or if the value of P is does not match any of the |
| 2693 | ** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0). |
| 2694 | ** |
| 2695 | ** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a |
| 2696 | ** 64-bit signed integer and returns that integer, or D if P does not |
| 2697 | ** exist. If the value of P is something other than an integer, then |
| 2698 | ** zero is returned. |
| 2699 | ** |
| 2700 | ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and |
| 2701 | ** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and |
| 2702 | ** is not a database file pathname pointer that SQLite passed into the xOpen |
| 2703 | ** VFS method, then the behavior of this routine is undefined and probably |
| 2704 | ** undesirable. |
| 2705 | */ |
| 2706 | SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam); |
| 2707 | SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault); |
| 2708 | SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64); |
| 2709 | |
| 2710 | |
| 2711 | /* |
| 2712 | ** CAPI3REF: Error Codes And Messages |
| 2713 | ** |
| 2714 | ** ^The sqlite3_errcode() interface returns the numeric [result code] or |
| 2715 | ** [extended result code] for the most recent failed sqlite3_* API call |
| 2716 | ** associated with a [database connection]. If a prior API call failed |
| 2717 | ** but the most recent API call succeeded, the return value from |
| 2718 | ** sqlite3_errcode() is undefined. ^The sqlite3_extended_errcode() |
| 2719 | ** interface is the same except that it always returns the |
| 2720 | ** [extended result code] even when extended result codes are |
| 2721 | ** disabled. |
| 2722 | ** |
| 2723 | ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language |
| 2724 | ** text that describes the error, as either UTF-8 or UTF-16 respectively. |
| 2725 | ** ^(Memory to hold the error message string is managed internally. |
| 2726 | ** The application does not need to worry about freeing the result. |
| 2727 | ** However, the error string might be overwritten or deallocated by |
| 2728 | ** subsequent calls to other SQLite interface functions.)^ |
| 2729 | ** |
| 2730 | ** When the serialized [threading mode] is in use, it might be the |
| 2731 | ** case that a second error occurs on a separate thread in between |
| 2732 | ** the time of the first error and the call to these interfaces. |
| 2733 | ** When that happens, the second error will be reported since these |
| 2734 | ** interfaces always report the most recent result. To avoid |
| 2735 | ** this, each thread can obtain exclusive use of the [database connection] D |
| 2736 | ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning |
| 2737 | ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after |
| 2738 | ** all calls to the interfaces listed here are completed. |
| 2739 | ** |
| 2740 | ** If an interface fails with SQLITE_MISUSE, that means the interface |
| 2741 | ** was invoked incorrectly by the application. In that case, the |
| 2742 | ** error code and message may or may not be set. |
| 2743 | */ |
| 2744 | SQLITE_API int sqlite3_errcode(sqlite3 *db); |
| 2745 | SQLITE_API int sqlite3_extended_errcode(sqlite3 *db); |
| 2746 | SQLITE_API const char *sqlite3_errmsg(sqlite3*); |
| 2747 | SQLITE_API const void *sqlite3_errmsg16(sqlite3*); |
| 2748 | |
| 2749 | /* |
| 2750 | ** CAPI3REF: SQL Statement Object |
| 2751 | ** KEYWORDS: {prepared statement} {prepared statements} |
| 2752 | ** |
| 2753 | ** An instance of this object represents a single SQL statement. |
| 2754 | ** This object is variously known as a "prepared statement" or a |
| 2755 | ** "compiled SQL statement" or simply as a "statement". |
| 2756 | ** |
| 2757 | ** The life of a statement object goes something like this: |
| 2758 | ** |
| 2759 | ** <ol> |
| 2760 | ** <li> Create the object using [sqlite3_prepare_v2()] or a related |
| 2761 | ** function. |
| 2762 | ** <li> Bind values to [host parameters] using the sqlite3_bind_*() |
| 2763 | ** interfaces. |
| 2764 | ** <li> Run the SQL by calling [sqlite3_step()] one or more times. |
| 2765 | ** <li> Reset the statement using [sqlite3_reset()] then go back |
| 2766 | ** to step 2. Do this zero or more times. |
| 2767 | ** <li> Destroy the object using [sqlite3_finalize()]. |
| 2768 | ** </ol> |
| 2769 | ** |
| 2770 | ** Refer to documentation on individual methods above for additional |
| 2771 | ** information. |
| 2772 | */ |
| 2773 | typedef struct sqlite3_stmt sqlite3_stmt; |
| 2774 | |
| 2775 | /* |
| 2776 | ** CAPI3REF: Run-time Limits |
| 2777 | ** |
| 2778 | ** ^(This interface allows the size of various constructs to be limited |
| 2779 | ** on a connection by connection basis. The first parameter is the |
| 2780 | ** [database connection] whose limit is to be set or queried. The |
| 2781 | ** second parameter is one of the [limit categories] that define a |
| 2782 | ** class of constructs to be size limited. The third parameter is the |
| 2783 | ** new limit for that construct.)^ |
| 2784 | ** |
| 2785 | ** ^If the new limit is a negative number, the limit is unchanged. |
| 2786 | ** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a |
| 2787 | ** [limits | hard upper bound] |
| 2788 | ** set at compile-time by a C preprocessor macro called |
| 2789 | ** [limits | SQLITE_MAX_<i>NAME</i>]. |
| 2790 | ** (The "_LIMIT_" in the name is changed to "_MAX_".))^ |
| 2791 | ** ^Attempts to increase a limit above its hard upper bound are |
| 2792 | ** silently truncated to the hard upper bound. |
| 2793 | ** |
| 2794 | ** ^Regardless of whether or not the limit was changed, the |
| 2795 | ** [sqlite3_limit()] interface returns the prior value of the limit. |
| 2796 | ** ^Hence, to find the current value of a limit without changing it, |
| 2797 | ** simply invoke this interface with the third parameter set to -1. |
| 2798 | ** |
| 2799 | ** Run-time limits are intended for use in applications that manage |
| 2800 | ** both their own internal database and also databases that are controlled |
| 2801 | ** by untrusted external sources. An example application might be a |
| 2802 | ** web browser that has its own databases for storing history and |
| 2803 | ** separate databases controlled by JavaScript applications downloaded |
| 2804 | ** off the Internet. The internal databases can be given the |
| 2805 | ** large, default limits. Databases managed by external sources can |
| 2806 | ** be given much smaller limits designed to prevent a denial of service |
| 2807 | ** attack. Developers might also want to use the [sqlite3_set_authorizer()] |
| 2808 | ** interface to further control untrusted SQL. The size of the database |
| 2809 | ** created by an untrusted script can be contained using the |
| 2810 | ** [max_page_count] [PRAGMA]. |
| 2811 | ** |
| 2812 | ** New run-time limit categories may be added in future releases. |
| 2813 | */ |
| 2814 | SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal); |
| 2815 | |
| 2816 | /* |
| 2817 | ** CAPI3REF: Run-Time Limit Categories |
| 2818 | ** KEYWORDS: {limit category} {*limit categories} |
| 2819 | ** |
| 2820 | ** These constants define various performance limits |
| 2821 | ** that can be lowered at run-time using [sqlite3_limit()]. |
| 2822 | ** The synopsis of the meanings of the various limits is shown below. |
| 2823 | ** Additional information is available at [limits | Limits in SQLite]. |
| 2824 | ** |
| 2825 | ** <dl> |
| 2826 | ** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt> |
| 2827 | ** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^ |
| 2828 | ** |
| 2829 | ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt> |
| 2830 | ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^ |
| 2831 | ** |
| 2832 | ** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt> |
| 2833 | ** <dd>The maximum number of columns in a table definition or in the |
| 2834 | ** result set of a [SELECT] or the maximum number of columns in an index |
| 2835 | ** or in an ORDER BY or GROUP BY clause.</dd>)^ |
| 2836 | ** |
| 2837 | ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt> |
| 2838 | ** <dd>The maximum depth of the parse tree on any expression.</dd>)^ |
| 2839 | ** |
| 2840 | ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt> |
| 2841 | ** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^ |
| 2842 | ** |
| 2843 | ** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt> |
| 2844 | ** <dd>The maximum number of instructions in a virtual machine program |
| 2845 | ** used to implement an SQL statement. This limit is not currently |
| 2846 | ** enforced, though that might be added in some future release of |
| 2847 | ** SQLite.</dd>)^ |
| 2848 | ** |
| 2849 | ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt> |
| 2850 | ** <dd>The maximum number of arguments on a function.</dd>)^ |
| 2851 | ** |
| 2852 | ** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt> |
| 2853 | ** <dd>The maximum number of [ATTACH | attached databases].)^</dd> |
| 2854 | ** |
| 2855 | ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]] |
| 2856 | ** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt> |
| 2857 | ** <dd>The maximum length of the pattern argument to the [LIKE] or |
| 2858 | ** [GLOB] operators.</dd>)^ |
| 2859 | ** |
| 2860 | ** [[SQLITE_LIMIT_VARIABLE_NUMBER]] |
| 2861 | ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt> |
| 2862 | ** <dd>The maximum index number of any [parameter] in an SQL statement.)^ |
| 2863 | ** |
| 2864 | ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt> |
| 2865 | ** <dd>The maximum depth of recursion for triggers.</dd>)^ |
| 2866 | ** </dl> |
| 2867 | */ |
| 2868 | #define SQLITE_LIMIT_LENGTH 0 |
| 2869 | #define SQLITE_LIMIT_SQL_LENGTH 1 |
| 2870 | #define SQLITE_LIMIT_COLUMN 2 |
| 2871 | #define SQLITE_LIMIT_EXPR_DEPTH 3 |
| 2872 | #define SQLITE_LIMIT_COMPOUND_SELECT 4 |
| 2873 | #define SQLITE_LIMIT_VDBE_OP 5 |
| 2874 | #define SQLITE_LIMIT_FUNCTION_ARG 6 |
| 2875 | #define SQLITE_LIMIT_ATTACHED 7 |
| 2876 | #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8 |
| 2877 | #define SQLITE_LIMIT_VARIABLE_NUMBER 9 |
| 2878 | #define SQLITE_LIMIT_TRIGGER_DEPTH 10 |
| 2879 | |
| 2880 | /* |
| 2881 | ** CAPI3REF: Compiling An SQL Statement |
| 2882 | ** KEYWORDS: {SQL statement compiler} |
| 2883 | ** |
| 2884 | ** To execute an SQL query, it must first be compiled into a byte-code |
| 2885 | ** program using one of these routines. |
| 2886 | ** |
| 2887 | ** The first argument, "db", is a [database connection] obtained from a |
| 2888 | ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or |
| 2889 | ** [sqlite3_open16()]. The database connection must not have been closed. |
| 2890 | ** |
| 2891 | ** The second argument, "zSql", is the statement to be compiled, encoded |
| 2892 | ** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2() |
| 2893 | ** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2() |
| 2894 | ** use UTF-16. |
| 2895 | ** |
| 2896 | ** ^If the nByte argument is less than zero, then zSql is read up to the |
| 2897 | ** first zero terminator. ^If nByte is non-negative, then it is the maximum |
| 2898 | ** number of bytes read from zSql. ^When nByte is non-negative, the |
| 2899 | ** zSql string ends at either the first '\000' or '\u0000' character or |
| 2900 | ** the nByte-th byte, whichever comes first. If the caller knows |
| 2901 | ** that the supplied string is nul-terminated, then there is a small |
| 2902 | ** performance advantage to be gained by passing an nByte parameter that |
| 2903 | ** is equal to the number of bytes in the input string <i>including</i> |
| 2904 | ** the nul-terminator bytes as this saves SQLite from having to |
| 2905 | ** make a copy of the input string. |
| 2906 | ** |
| 2907 | ** ^If pzTail is not NULL then *pzTail is made to point to the first byte |
| 2908 | ** past the end of the first SQL statement in zSql. These routines only |
| 2909 | ** compile the first statement in zSql, so *pzTail is left pointing to |
| 2910 | ** what remains uncompiled. |
| 2911 | ** |
| 2912 | ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be |
| 2913 | ** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set |
| 2914 | ** to NULL. ^If the input text contains no SQL (if the input is an empty |
| 2915 | ** string or a comment) then *ppStmt is set to NULL. |
| 2916 | ** The calling procedure is responsible for deleting the compiled |
| 2917 | ** SQL statement using [sqlite3_finalize()] after it has finished with it. |
| 2918 | ** ppStmt may not be NULL. |
| 2919 | ** |
| 2920 | ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK]; |
| 2921 | ** otherwise an [error code] is returned. |
| 2922 | ** |
| 2923 | ** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are |
| 2924 | ** recommended for all new programs. The two older interfaces are retained |
| 2925 | ** for backwards compatibility, but their use is discouraged. |
| 2926 | ** ^In the "v2" interfaces, the prepared statement |
| 2927 | ** that is returned (the [sqlite3_stmt] object) contains a copy of the |
| 2928 | ** original SQL text. This causes the [sqlite3_step()] interface to |
| 2929 | ** behave differently in three ways: |
| 2930 | ** |
| 2931 | ** <ol> |
| 2932 | ** <li> |
| 2933 | ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it |
| 2934 | ** always used to do, [sqlite3_step()] will automatically recompile the SQL |
| 2935 | ** statement and try to run it again. |
| 2936 | ** </li> |
| 2937 | ** |
| 2938 | ** <li> |
| 2939 | ** ^When an error occurs, [sqlite3_step()] will return one of the detailed |
| 2940 | ** [error codes] or [extended error codes]. ^The legacy behavior was that |
| 2941 | ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code |
| 2942 | ** and the application would have to make a second call to [sqlite3_reset()] |
| 2943 | ** in order to find the underlying cause of the problem. With the "v2" prepare |
| 2944 | ** interfaces, the underlying reason for the error is returned immediately. |
| 2945 | ** </li> |
| 2946 | ** |
| 2947 | ** <li> |
| 2948 | ** ^If the specific value bound to [parameter | host parameter] in the |
| 2949 | ** WHERE clause might influence the choice of query plan for a statement, |
| 2950 | ** then the statement will be automatically recompiled, as if there had been |
| 2951 | ** a schema change, on the first [sqlite3_step()] call following any change |
| 2952 | ** to the [sqlite3_bind_text | bindings] of that [parameter]. |
| 2953 | ** ^The specific value of WHERE-clause [parameter] might influence the |
| 2954 | ** choice of query plan if the parameter is the left-hand side of a [LIKE] |
| 2955 | ** or [GLOB] operator or if the parameter is compared to an indexed column |
| 2956 | ** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled. |
| 2957 | ** the |
| 2958 | ** </li> |
| 2959 | ** </ol> |
| 2960 | */ |
| 2961 | SQLITE_API int sqlite3_prepare( |
| 2962 | sqlite3 *db, /* Database handle */ |
| 2963 | const char *zSql, /* SQL statement, UTF-8 encoded */ |
| 2964 | int nByte, /* Maximum length of zSql in bytes. */ |
| 2965 | sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
| 2966 | const char **pzTail /* OUT: Pointer to unused portion of zSql */ |
| 2967 | ); |
| 2968 | SQLITE_API int sqlite3_prepare_v2( |
| 2969 | sqlite3 *db, /* Database handle */ |
| 2970 | const char *zSql, /* SQL statement, UTF-8 encoded */ |
| 2971 | int nByte, /* Maximum length of zSql in bytes. */ |
| 2972 | sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
| 2973 | const char **pzTail /* OUT: Pointer to unused portion of zSql */ |
| 2974 | ); |
| 2975 | SQLITE_API int sqlite3_prepare16( |
| 2976 | sqlite3 *db, /* Database handle */ |
| 2977 | const void *zSql, /* SQL statement, UTF-16 encoded */ |
| 2978 | int nByte, /* Maximum length of zSql in bytes. */ |
| 2979 | sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
| 2980 | const void **pzTail /* OUT: Pointer to unused portion of zSql */ |
| 2981 | ); |
| 2982 | SQLITE_API int sqlite3_prepare16_v2( |
| 2983 | sqlite3 *db, /* Database handle */ |
| 2984 | const void *zSql, /* SQL statement, UTF-16 encoded */ |
| 2985 | int nByte, /* Maximum length of zSql in bytes. */ |
| 2986 | sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
| 2987 | const void **pzTail /* OUT: Pointer to unused portion of zSql */ |
| 2988 | ); |
| 2989 | |
| 2990 | /* |
| 2991 | ** CAPI3REF: Retrieving Statement SQL |
| 2992 | ** |
| 2993 | ** ^This interface can be used to retrieve a saved copy of the original |
| 2994 | ** SQL text used to create a [prepared statement] if that statement was |
| 2995 | ** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()]. |
| 2996 | */ |
| 2997 | SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt); |
| 2998 | |
| 2999 | /* |
| 3000 | ** CAPI3REF: Determine If An SQL Statement Writes The Database |
| 3001 | ** |
| 3002 | ** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if |
| 3003 | ** and only if the [prepared statement] X makes no direct changes to |
| 3004 | ** the content of the database file. |
| 3005 | ** |
| 3006 | ** Note that [application-defined SQL functions] or |
| 3007 | ** [virtual tables] might change the database indirectly as a side effect. |
| 3008 | ** ^(For example, if an application defines a function "eval()" that |
| 3009 | ** calls [sqlite3_exec()], then the following SQL statement would |
| 3010 | ** change the database file through side-effects: |
| 3011 | ** |
| 3012 | ** <blockquote><pre> |
| 3013 | ** SELECT eval('DELETE FROM t1') FROM t2; |
| 3014 | ** </pre></blockquote> |
| 3015 | ** |
| 3016 | ** But because the [SELECT] statement does not change the database file |
| 3017 | ** directly, sqlite3_stmt_readonly() would still return true.)^ |
| 3018 | ** |
| 3019 | ** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK], |
| 3020 | ** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true, |
| 3021 | ** since the statements themselves do not actually modify the database but |
| 3022 | ** rather they control the timing of when other statements modify the |
| 3023 | ** database. ^The [ATTACH] and [DETACH] statements also cause |
| 3024 | ** sqlite3_stmt_readonly() to return true since, while those statements |
| 3025 | ** change the configuration of a database connection, they do not make |
| 3026 | ** changes to the content of the database files on disk. |
| 3027 | */ |
| 3028 | SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt); |
| 3029 | |
| 3030 | /* |
| 3031 | ** CAPI3REF: Determine If A Prepared Statement Has Been Reset |
| 3032 | ** |
| 3033 | ** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the |
| 3034 | ** [prepared statement] S has been stepped at least once using |
| 3035 | ** [sqlite3_step(S)] but has not run to completion and/or has not |
| 3036 | ** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S) |
| 3037 | ** interface returns false if S is a NULL pointer. If S is not a |
| 3038 | ** NULL pointer and is not a pointer to a valid [prepared statement] |
| 3039 | ** object, then the behavior is undefined and probably undesirable. |
| 3040 | ** |
| 3041 | ** This interface can be used in combination [sqlite3_next_stmt()] |
| 3042 | ** to locate all prepared statements associated with a database |
| 3043 | ** connection that are in need of being reset. This can be used, |
| 3044 | ** for example, in diagnostic routines to search for prepared |
| 3045 | ** statements that are holding a transaction open. |
| 3046 | */ |
| 3047 | SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*); |
| 3048 | |
| 3049 | /* |
| 3050 | ** CAPI3REF: Dynamically Typed Value Object |
| 3051 | ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} |
| 3052 | ** |
| 3053 | ** SQLite uses the sqlite3_value object to represent all values |
| 3054 | ** that can be stored in a database table. SQLite uses dynamic typing |
| 3055 | ** for the values it stores. ^Values stored in sqlite3_value objects |
| 3056 | ** can be integers, floating point values, strings, BLOBs, or NULL. |
| 3057 | ** |
| 3058 | ** An sqlite3_value object may be either "protected" or "unprotected". |
| 3059 | ** Some interfaces require a protected sqlite3_value. Other interfaces |
| 3060 | ** will accept either a protected or an unprotected sqlite3_value. |
| 3061 | ** Every interface that accepts sqlite3_value arguments specifies |
| 3062 | ** whether or not it requires a protected sqlite3_value. |
| 3063 | ** |
| 3064 | ** The terms "protected" and "unprotected" refer to whether or not |
| 3065 | ** a mutex is held. An internal mutex is held for a protected |
| 3066 | ** sqlite3_value object but no mutex is held for an unprotected |
| 3067 | ** sqlite3_value object. If SQLite is compiled to be single-threaded |
| 3068 | ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0) |
| 3069 | ** or if SQLite is run in one of reduced mutex modes |
| 3070 | ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD] |
| 3071 | ** then there is no distinction between protected and unprotected |
| 3072 | ** sqlite3_value objects and they can be used interchangeably. However, |
| 3073 | ** for maximum code portability it is recommended that applications |
| 3074 | ** still make the distinction between protected and unprotected |
| 3075 | ** sqlite3_value objects even when not strictly required. |
| 3076 | ** |
| 3077 | ** ^The sqlite3_value objects that are passed as parameters into the |
| 3078 | ** implementation of [application-defined SQL functions] are protected. |
| 3079 | ** ^The sqlite3_value object returned by |
| 3080 | ** [sqlite3_column_value()] is unprotected. |
| 3081 | ** Unprotected sqlite3_value objects may only be used with |
| 3082 | ** [sqlite3_result_value()] and [sqlite3_bind_value()]. |
| 3083 | ** The [sqlite3_value_blob | sqlite3_value_type()] family of |
| 3084 | ** interfaces require protected sqlite3_value objects. |
| 3085 | */ |
| 3086 | typedef struct Mem sqlite3_value; |
| 3087 | |
| 3088 | /* |
| 3089 | ** CAPI3REF: SQL Function Context Object |
| 3090 | ** |
| 3091 | ** The context in which an SQL function executes is stored in an |
| 3092 | ** sqlite3_context object. ^A pointer to an sqlite3_context object |
| 3093 | ** is always first parameter to [application-defined SQL functions]. |
| 3094 | ** The application-defined SQL function implementation will pass this |
| 3095 | ** pointer through into calls to [sqlite3_result_int | sqlite3_result()], |
| 3096 | ** [sqlite3_aggregate_context()], [sqlite3_user_data()], |
| 3097 | ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()], |
| 3098 | ** and/or [sqlite3_set_auxdata()]. |
| 3099 | */ |
| 3100 | typedef struct sqlite3_context sqlite3_context; |
| 3101 | |
| 3102 | /* |
| 3103 | ** CAPI3REF: Binding Values To Prepared Statements |
| 3104 | ** KEYWORDS: {host parameter} {host parameters} {host parameter name} |
| 3105 | ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding} |
| 3106 | ** |
| 3107 | ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants, |
| 3108 | ** literals may be replaced by a [parameter] that matches one of following |
| 3109 | ** templates: |
| 3110 | ** |
| 3111 | ** <ul> |
| 3112 | ** <li> ? |
| 3113 | ** <li> ?NNN |
| 3114 | ** <li> :VVV |
| 3115 | ** <li> @VVV |
| 3116 | ** <li> $VVV |
| 3117 | ** </ul> |
| 3118 | ** |
| 3119 | ** In the templates above, NNN represents an integer literal, |
| 3120 | ** and VVV represents an alphanumeric identifier.)^ ^The values of these |
| 3121 | ** parameters (also called "host parameter names" or "SQL parameters") |
| 3122 | ** can be set using the sqlite3_bind_*() routines defined here. |
| 3123 | ** |
| 3124 | ** ^The first argument to the sqlite3_bind_*() routines is always |
| 3125 | ** a pointer to the [sqlite3_stmt] object returned from |
| 3126 | ** [sqlite3_prepare_v2()] or its variants. |
| 3127 | ** |
| 3128 | ** ^The second argument is the index of the SQL parameter to be set. |
| 3129 | ** ^The leftmost SQL parameter has an index of 1. ^When the same named |
| 3130 | ** SQL parameter is used more than once, second and subsequent |
| 3131 | ** occurrences have the same index as the first occurrence. |
| 3132 | ** ^The index for named parameters can be looked up using the |
| 3133 | ** [sqlite3_bind_parameter_index()] API if desired. ^The index |
| 3134 | ** for "?NNN" parameters is the value of NNN. |
| 3135 | ** ^The NNN value must be between 1 and the [sqlite3_limit()] |
| 3136 | ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999). |
| 3137 | ** |
| 3138 | ** ^The third argument is the value to bind to the parameter. |
| 3139 | ** |
| 3140 | ** ^(In those routines that have a fourth argument, its value is the |
| 3141 | ** number of bytes in the parameter. To be clear: the value is the |
| 3142 | ** number of <u>bytes</u> in the value, not the number of characters.)^ |
| 3143 | ** ^If the fourth parameter is negative, the length of the string is |
| 3144 | ** the number of bytes up to the first zero terminator. |
| 3145 | ** If a non-negative fourth parameter is provided to sqlite3_bind_text() |
| 3146 | ** or sqlite3_bind_text16() then that parameter must be the byte offset |
| 3147 | ** where the NUL terminator would occur assuming the string were NUL |
| 3148 | ** terminated. If any NUL characters occur at byte offsets less than |
| 3149 | ** the value of the fourth parameter then the resulting string value will |
| 3150 | ** contain embedded NULs. The result of expressions involving strings |
| 3151 | ** with embedded NULs is undefined. |
| 3152 | ** |
| 3153 | ** ^The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and |
| 3154 | ** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or |
| 3155 | ** string after SQLite has finished with it. ^The destructor is called |
| 3156 | ** to dispose of the BLOB or string even if the call to sqlite3_bind_blob(), |
| 3157 | ** sqlite3_bind_text(), or sqlite3_bind_text16() fails. |
| 3158 | ** ^If the fifth argument is |
| 3159 | ** the special value [SQLITE_STATIC], then SQLite assumes that the |
| 3160 | ** information is in static, unmanaged space and does not need to be freed. |
| 3161 | ** ^If the fifth argument has the value [SQLITE_TRANSIENT], then |
| 3162 | ** SQLite makes its own private copy of the data immediately, before |
| 3163 | ** the sqlite3_bind_*() routine returns. |
| 3164 | ** |
| 3165 | ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that |
| 3166 | ** is filled with zeroes. ^A zeroblob uses a fixed amount of memory |
| 3167 | ** (just an integer to hold its size) while it is being processed. |
| 3168 | ** Zeroblobs are intended to serve as placeholders for BLOBs whose |
| 3169 | ** content is later written using |
| 3170 | ** [sqlite3_blob_open | incremental BLOB I/O] routines. |
| 3171 | ** ^A negative value for the zeroblob results in a zero-length BLOB. |
| 3172 | ** |
| 3173 | ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer |
| 3174 | ** for the [prepared statement] or with a prepared statement for which |
| 3175 | ** [sqlite3_step()] has been called more recently than [sqlite3_reset()], |
| 3176 | ** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_() |
| 3177 | ** routine is passed a [prepared statement] that has been finalized, the |
| 3178 | ** result is undefined and probably harmful. |
| 3179 | ** |
| 3180 | ** ^Bindings are not cleared by the [sqlite3_reset()] routine. |
| 3181 | ** ^Unbound parameters are interpreted as NULL. |
| 3182 | ** |
| 3183 | ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an |
| 3184 | ** [error code] if anything goes wrong. |
| 3185 | ** ^[SQLITE_RANGE] is returned if the parameter |
| 3186 | ** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails. |
| 3187 | ** |
| 3188 | ** See also: [sqlite3_bind_parameter_count()], |
| 3189 | ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()]. |
| 3190 | */ |
| 3191 | SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*)); |
| 3192 | SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double); |
| 3193 | SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int); |
| 3194 | SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); |
| 3195 | SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int); |
| 3196 | SQLITE_API int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*)); |
| 3197 | SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*)); |
| 3198 | SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); |
| 3199 | SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); |
| 3200 | |
| 3201 | /* |
| 3202 | ** CAPI3REF: Number Of SQL Parameters |
| 3203 | ** |
| 3204 | ** ^This routine can be used to find the number of [SQL parameters] |
| 3205 | ** in a [prepared statement]. SQL parameters are tokens of the |
| 3206 | ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as |
| 3207 | ** placeholders for values that are [sqlite3_bind_blob | bound] |
| 3208 | ** to the parameters at a later time. |
| 3209 | ** |
| 3210 | ** ^(This routine actually returns the index of the largest (rightmost) |
| 3211 | ** parameter. For all forms except ?NNN, this will correspond to the |
| 3212 | ** number of unique parameters. If parameters of the ?NNN form are used, |
| 3213 | ** there may be gaps in the list.)^ |
| 3214 | ** |
| 3215 | ** See also: [sqlite3_bind_blob|sqlite3_bind()], |
| 3216 | ** [sqlite3_bind_parameter_name()], and |
| 3217 | ** [sqlite3_bind_parameter_index()]. |
| 3218 | */ |
| 3219 | SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*); |
| 3220 | |
| 3221 | /* |
| 3222 | ** CAPI3REF: Name Of A Host Parameter |
| 3223 | ** |
| 3224 | ** ^The sqlite3_bind_parameter_name(P,N) interface returns |
| 3225 | ** the name of the N-th [SQL parameter] in the [prepared statement] P. |
| 3226 | ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA" |
| 3227 | ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA" |
| 3228 | ** respectively. |
| 3229 | ** In other words, the initial ":" or "$" or "@" or "?" |
| 3230 | ** is included as part of the name.)^ |
| 3231 | ** ^Parameters of the form "?" without a following integer have no name |
| 3232 | ** and are referred to as "nameless" or "anonymous parameters". |
| 3233 | ** |
| 3234 | ** ^The first host parameter has an index of 1, not 0. |
| 3235 | ** |
| 3236 | ** ^If the value N is out of range or if the N-th parameter is |
| 3237 | ** nameless, then NULL is returned. ^The returned string is |
| 3238 | ** always in UTF-8 encoding even if the named parameter was |
| 3239 | ** originally specified as UTF-16 in [sqlite3_prepare16()] or |
| 3240 | ** [sqlite3_prepare16_v2()]. |
| 3241 | ** |
| 3242 | ** See also: [sqlite3_bind_blob|sqlite3_bind()], |
| 3243 | ** [sqlite3_bind_parameter_count()], and |
| 3244 | ** [sqlite3_bind_parameter_index()]. |
| 3245 | */ |
| 3246 | SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); |
| 3247 | |
| 3248 | /* |
| 3249 | ** CAPI3REF: Index Of A Parameter With A Given Name |
| 3250 | ** |
| 3251 | ** ^Return the index of an SQL parameter given its name. ^The |
| 3252 | ** index value returned is suitable for use as the second |
| 3253 | ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero |
| 3254 | ** is returned if no matching parameter is found. ^The parameter |
| 3255 | ** name must be given in UTF-8 even if the original statement |
| 3256 | ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()]. |
| 3257 | ** |
| 3258 | ** See also: [sqlite3_bind_blob|sqlite3_bind()], |
| 3259 | ** [sqlite3_bind_parameter_count()], and |
| 3260 | ** [sqlite3_bind_parameter_index()]. |
| 3261 | */ |
| 3262 | SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); |
| 3263 | |
| 3264 | /* |
| 3265 | ** CAPI3REF: Reset All Bindings On A Prepared Statement |
| 3266 | ** |
| 3267 | ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset |
| 3268 | ** the [sqlite3_bind_blob | bindings] on a [prepared statement]. |
| 3269 | ** ^Use this routine to reset all host parameters to NULL. |
| 3270 | */ |
| 3271 | SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*); |
| 3272 | |
| 3273 | /* |
| 3274 | ** CAPI3REF: Number Of Columns In A Result Set |
| 3275 | ** |
| 3276 | ** ^Return the number of columns in the result set returned by the |
| 3277 | ** [prepared statement]. ^This routine returns 0 if pStmt is an SQL |
| 3278 | ** statement that does not return data (for example an [UPDATE]). |
| 3279 | ** |
| 3280 | ** See also: [sqlite3_data_count()] |
| 3281 | */ |
| 3282 | SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt); |
| 3283 | |
| 3284 | /* |
| 3285 | ** CAPI3REF: Column Names In A Result Set |
| 3286 | ** |
| 3287 | ** ^These routines return the name assigned to a particular column |
| 3288 | ** in the result set of a [SELECT] statement. ^The sqlite3_column_name() |
| 3289 | ** interface returns a pointer to a zero-terminated UTF-8 string |
| 3290 | ** and sqlite3_column_name16() returns a pointer to a zero-terminated |
| 3291 | ** UTF-16 string. ^The first parameter is the [prepared statement] |
| 3292 | ** that implements the [SELECT] statement. ^The second parameter is the |
| 3293 | ** column number. ^The leftmost column is number 0. |
| 3294 | ** |
| 3295 | ** ^The returned string pointer is valid until either the [prepared statement] |
| 3296 | ** is destroyed by [sqlite3_finalize()] or until the statement is automatically |
| 3297 | ** reprepared by the first call to [sqlite3_step()] for a particular run |
| 3298 | ** or until the next call to |
| 3299 | ** sqlite3_column_name() or sqlite3_column_name16() on the same column. |
| 3300 | ** |
| 3301 | ** ^If sqlite3_malloc() fails during the processing of either routine |
| 3302 | ** (for example during a conversion from UTF-8 to UTF-16) then a |
| 3303 | ** NULL pointer is returned. |
| 3304 | ** |
| 3305 | ** ^The name of a result column is the value of the "AS" clause for |
| 3306 | ** that column, if there is an AS clause. If there is no AS clause |
| 3307 | ** then the name of the column is unspecified and may change from |
| 3308 | ** one release of SQLite to the next. |
| 3309 | */ |
| 3310 | SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N); |
| 3311 | SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N); |
| 3312 | |
| 3313 | /* |
| 3314 | ** CAPI3REF: Source Of Data In A Query Result |
| 3315 | ** |
| 3316 | ** ^These routines provide a means to determine the database, table, and |
| 3317 | ** table column that is the origin of a particular result column in |
| 3318 | ** [SELECT] statement. |
| 3319 | ** ^The name of the database or table or column can be returned as |
| 3320 | ** either a UTF-8 or UTF-16 string. ^The _database_ routines return |
| 3321 | ** the database name, the _table_ routines return the table name, and |
| 3322 | ** the origin_ routines return the column name. |
| 3323 | ** ^The returned string is valid until the [prepared statement] is destroyed |
| 3324 | ** using [sqlite3_finalize()] or until the statement is automatically |
| 3325 | ** reprepared by the first call to [sqlite3_step()] for a particular run |
| 3326 | ** or until the same information is requested |
| 3327 | ** again in a different encoding. |
| 3328 | ** |
| 3329 | ** ^The names returned are the original un-aliased names of the |
| 3330 | ** database, table, and column. |
| 3331 | ** |
| 3332 | ** ^The first argument to these interfaces is a [prepared statement]. |
| 3333 | ** ^These functions return information about the Nth result column returned by |
| 3334 | ** the statement, where N is the second function argument. |
| 3335 | ** ^The left-most column is column 0 for these routines. |
| 3336 | ** |
| 3337 | ** ^If the Nth column returned by the statement is an expression or |
| 3338 | ** subquery and is not a column value, then all of these functions return |
| 3339 | ** NULL. ^These routine might also return NULL if a memory allocation error |
| 3340 | ** occurs. ^Otherwise, they return the name of the attached database, table, |
| 3341 | ** or column that query result column was extracted from. |
| 3342 | ** |
| 3343 | ** ^As with all other SQLite APIs, those whose names end with "16" return |
| 3344 | ** UTF-16 encoded strings and the other functions return UTF-8. |
| 3345 | ** |
| 3346 | ** ^These APIs are only available if the library was compiled with the |
| 3347 | ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol. |
| 3348 | ** |
| 3349 | ** If two or more threads call one or more of these routines against the same |
| 3350 | ** prepared statement and column at the same time then the results are |
| 3351 | ** undefined. |
| 3352 | ** |
| 3353 | ** If two or more threads call one or more |
| 3354 | ** [sqlite3_column_database_name | column metadata interfaces] |
| 3355 | ** for the same [prepared statement] and result column |
| 3356 | ** at the same time then the results are undefined. |
| 3357 | */ |
| 3358 | SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int); |
| 3359 | SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int); |
| 3360 | SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int); |
| 3361 | SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int); |
| 3362 | SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int); |
| 3363 | SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int); |
| 3364 | |
| 3365 | /* |
| 3366 | ** CAPI3REF: Declared Datatype Of A Query Result |
| 3367 | ** |
| 3368 | ** ^(The first parameter is a [prepared statement]. |
| 3369 | ** If this statement is a [SELECT] statement and the Nth column of the |
| 3370 | ** returned result set of that [SELECT] is a table column (not an |
| 3371 | ** expression or subquery) then the declared type of the table |
| 3372 | ** column is returned.)^ ^If the Nth column of the result set is an |
| 3373 | ** expression or subquery, then a NULL pointer is returned. |
| 3374 | ** ^The returned string is always UTF-8 encoded. |
| 3375 | ** |
| 3376 | ** ^(For example, given the database schema: |
| 3377 | ** |
| 3378 | ** CREATE TABLE t1(c1 VARIANT); |
| 3379 | ** |
| 3380 | ** and the following statement to be compiled: |
| 3381 | ** |
| 3382 | ** SELECT c1 + 1, c1 FROM t1; |
| 3383 | ** |
| 3384 | ** this routine would return the string "VARIANT" for the second result |
| 3385 | ** column (i==1), and a NULL pointer for the first result column (i==0).)^ |
| 3386 | ** |
| 3387 | ** ^SQLite uses dynamic run-time typing. ^So just because a column |
| 3388 | ** is declared to contain a particular type does not mean that the |
| 3389 | ** data stored in that column is of the declared type. SQLite is |
| 3390 | ** strongly typed, but the typing is dynamic not static. ^Type |
| 3391 | ** is associated with individual values, not with the containers |
| 3392 | ** used to hold those values. |
| 3393 | */ |
| 3394 | SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int); |
| 3395 | SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int); |
| 3396 | |
| 3397 | /* |
| 3398 | ** CAPI3REF: Evaluate An SQL Statement |
| 3399 | ** |
| 3400 | ** After a [prepared statement] has been prepared using either |
| 3401 | ** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy |
| 3402 | ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function |
| 3403 | ** must be called one or more times to evaluate the statement. |
| 3404 | ** |
| 3405 | ** The details of the behavior of the sqlite3_step() interface depend |
| 3406 | ** on whether the statement was prepared using the newer "v2" interface |
| 3407 | ** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy |
| 3408 | ** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the |
| 3409 | ** new "v2" interface is recommended for new applications but the legacy |
| 3410 | ** interface will continue to be supported. |
| 3411 | ** |
| 3412 | ** ^In the legacy interface, the return value will be either [SQLITE_BUSY], |
| 3413 | ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. |
| 3414 | ** ^With the "v2" interface, any of the other [result codes] or |
| 3415 | ** [extended result codes] might be returned as well. |
| 3416 | ** |
| 3417 | ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the |
| 3418 | ** database locks it needs to do its job. ^If the statement is a [COMMIT] |
| 3419 | ** or occurs outside of an explicit transaction, then you can retry the |
| 3420 | ** statement. If the statement is not a [COMMIT] and occurs within an |
| 3421 | ** explicit transaction then you should rollback the transaction before |
| 3422 | ** continuing. |
| 3423 | ** |
| 3424 | ** ^[SQLITE_DONE] means that the statement has finished executing |
| 3425 | ** successfully. sqlite3_step() should not be called again on this virtual |
| 3426 | ** machine without first calling [sqlite3_reset()] to reset the virtual |
| 3427 | ** machine back to its initial state. |
| 3428 | ** |
| 3429 | ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW] |
| 3430 | ** is returned each time a new row of data is ready for processing by the |
| 3431 | ** caller. The values may be accessed using the [column access functions]. |
| 3432 | ** sqlite3_step() is called again to retrieve the next row of data. |
| 3433 | ** |
| 3434 | ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint |
| 3435 | ** violation) has occurred. sqlite3_step() should not be called again on |
| 3436 | ** the VM. More information may be found by calling [sqlite3_errmsg()]. |
| 3437 | ** ^With the legacy interface, a more specific error code (for example, |
| 3438 | ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) |
| 3439 | ** can be obtained by calling [sqlite3_reset()] on the |
| 3440 | ** [prepared statement]. ^In the "v2" interface, |
| 3441 | ** the more specific error code is returned directly by sqlite3_step(). |
| 3442 | ** |
| 3443 | ** [SQLITE_MISUSE] means that the this routine was called inappropriately. |
| 3444 | ** Perhaps it was called on a [prepared statement] that has |
| 3445 | ** already been [sqlite3_finalize | finalized] or on one that had |
| 3446 | ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could |
| 3447 | ** be the case that the same database connection is being used by two or |
| 3448 | ** more threads at the same moment in time. |
| 3449 | ** |
| 3450 | ** For all versions of SQLite up to and including 3.6.23.1, a call to |
| 3451 | ** [sqlite3_reset()] was required after sqlite3_step() returned anything |
| 3452 | ** other than [SQLITE_ROW] before any subsequent invocation of |
| 3453 | ** sqlite3_step(). Failure to reset the prepared statement using |
| 3454 | ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from |
| 3455 | ** sqlite3_step(). But after version 3.6.23.1, sqlite3_step() began |
| 3456 | ** calling [sqlite3_reset()] automatically in this circumstance rather |
| 3457 | ** than returning [SQLITE_MISUSE]. This is not considered a compatibility |
| 3458 | ** break because any application that ever receives an SQLITE_MISUSE error |
| 3459 | ** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option |
| 3460 | ** can be used to restore the legacy behavior. |
| 3461 | ** |
| 3462 | ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step() |
| 3463 | ** API always returns a generic error code, [SQLITE_ERROR], following any |
| 3464 | ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call |
| 3465 | ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the |
| 3466 | ** specific [error codes] that better describes the error. |
| 3467 | ** We admit that this is a goofy design. The problem has been fixed |
| 3468 | ** with the "v2" interface. If you prepare all of your SQL statements |
| 3469 | ** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead |
| 3470 | ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces, |
| 3471 | ** then the more specific [error codes] are returned directly |
| 3472 | ** by sqlite3_step(). The use of the "v2" interface is recommended. |
| 3473 | */ |
| 3474 | SQLITE_API int sqlite3_step(sqlite3_stmt*); |
| 3475 | |
| 3476 | /* |
| 3477 | ** CAPI3REF: Number of columns in a result set |
| 3478 | ** |
| 3479 | ** ^The sqlite3_data_count(P) interface returns the number of columns in the |
| 3480 | ** current row of the result set of [prepared statement] P. |
| 3481 | ** ^If prepared statement P does not have results ready to return |
| 3482 | ** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of |
| 3483 | ** interfaces) then sqlite3_data_count(P) returns 0. |
| 3484 | ** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer. |
| 3485 | ** ^The sqlite3_data_count(P) routine returns 0 if the previous call to |
| 3486 | ** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P) |
| 3487 | ** will return non-zero if previous call to [sqlite3_step](P) returned |
| 3488 | ** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum] |
| 3489 | ** where it always returns zero since each step of that multi-step |
| 3490 | ** pragma returns 0 columns of data. |
| 3491 | ** |
| 3492 | ** See also: [sqlite3_column_count()] |
| 3493 | */ |
| 3494 | SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt); |
| 3495 | |
| 3496 | /* |
| 3497 | ** CAPI3REF: Fundamental Datatypes |
| 3498 | ** KEYWORDS: SQLITE_TEXT |
| 3499 | ** |
| 3500 | ** ^(Every value in SQLite has one of five fundamental datatypes: |
| 3501 | ** |
| 3502 | ** <ul> |
| 3503 | ** <li> 64-bit signed integer |
| 3504 | ** <li> 64-bit IEEE floating point number |
| 3505 | ** <li> string |
| 3506 | ** <li> BLOB |
| 3507 | ** <li> NULL |
| 3508 | ** </ul>)^ |
| 3509 | ** |
| 3510 | ** These constants are codes for each of those types. |
| 3511 | ** |
| 3512 | ** Note that the SQLITE_TEXT constant was also used in SQLite version 2 |
| 3513 | ** for a completely different meaning. Software that links against both |
| 3514 | ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not |
| 3515 | ** SQLITE_TEXT. |
| 3516 | */ |
| 3517 | #define SQLITE_INTEGER 1 |
| 3518 | #define SQLITE_FLOAT 2 |
| 3519 | #define SQLITE_BLOB 4 |
| 3520 | #define SQLITE_NULL 5 |
| 3521 | #ifdef SQLITE_TEXT |
| 3522 | # undef SQLITE_TEXT |
| 3523 | #else |
| 3524 | # define SQLITE_TEXT 3 |
| 3525 | #endif |
| 3526 | #define SQLITE3_TEXT 3 |
| 3527 | |
| 3528 | /* |
| 3529 | ** CAPI3REF: Result Values From A Query |
| 3530 | ** KEYWORDS: {column access functions} |
| 3531 | ** |
| 3532 | ** These routines form the "result set" interface. |
| 3533 | ** |
| 3534 | ** ^These routines return information about a single column of the current |
| 3535 | ** result row of a query. ^In every case the first argument is a pointer |
| 3536 | ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*] |
| 3537 | ** that was returned from [sqlite3_prepare_v2()] or one of its variants) |
| 3538 | ** and the second argument is the index of the column for which information |
| 3539 | ** should be returned. ^The leftmost column of the result set has the index 0. |
| 3540 | ** ^The number of columns in the result can be determined using |
| 3541 | ** [sqlite3_column_count()]. |
| 3542 | ** |
| 3543 | ** If the SQL statement does not currently point to a valid row, or if the |
| 3544 | ** column index is out of range, the result is undefined. |
| 3545 | ** These routines may only be called when the most recent call to |
| 3546 | ** [sqlite3_step()] has returned [SQLITE_ROW] and neither |
| 3547 | ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently. |
| 3548 | ** If any of these routines are called after [sqlite3_reset()] or |
| 3549 | ** [sqlite3_finalize()] or after [sqlite3_step()] has returned |
| 3550 | ** something other than [SQLITE_ROW], the results are undefined. |
| 3551 | ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] |
| 3552 | ** are called from a different thread while any of these routines |
| 3553 | ** are pending, then the results are undefined. |
| 3554 | ** |
| 3555 | ** ^The sqlite3_column_type() routine returns the |
| 3556 | ** [SQLITE_INTEGER | datatype code] for the initial data type |
| 3557 | ** of the result column. ^The returned value is one of [SQLITE_INTEGER], |
| 3558 | ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value |
| 3559 | ** returned by sqlite3_column_type() is only meaningful if no type |
| 3560 | ** conversions have occurred as described below. After a type conversion, |
| 3561 | ** the value returned by sqlite3_column_type() is undefined. Future |
| 3562 | ** versions of SQLite may change the behavior of sqlite3_column_type() |
| 3563 | ** following a type conversion. |
| 3564 | ** |
| 3565 | ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() |
| 3566 | ** routine returns the number of bytes in that BLOB or string. |
| 3567 | ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts |
| 3568 | ** the string to UTF-8 and then returns the number of bytes. |
| 3569 | ** ^If the result is a numeric value then sqlite3_column_bytes() uses |
| 3570 | ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns |
| 3571 | ** the number of bytes in that string. |
| 3572 | ** ^If the result is NULL, then sqlite3_column_bytes() returns zero. |
| 3573 | ** |
| 3574 | ** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16() |
| 3575 | ** routine returns the number of bytes in that BLOB or string. |
| 3576 | ** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts |
| 3577 | ** the string to UTF-16 and then returns the number of bytes. |
| 3578 | ** ^If the result is a numeric value then sqlite3_column_bytes16() uses |
| 3579 | ** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns |
| 3580 | ** the number of bytes in that string. |
| 3581 | ** ^If the result is NULL, then sqlite3_column_bytes16() returns zero. |
| 3582 | ** |
| 3583 | ** ^The values returned by [sqlite3_column_bytes()] and |
| 3584 | ** [sqlite3_column_bytes16()] do not include the zero terminators at the end |
| 3585 | ** of the string. ^For clarity: the values returned by |
| 3586 | ** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of |
| 3587 | ** bytes in the string, not the number of characters. |
| 3588 | ** |
| 3589 | ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(), |
| 3590 | ** even empty strings, are always zero-terminated. ^The return |
| 3591 | ** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer. |
| 3592 | ** |
| 3593 | ** ^The object returned by [sqlite3_column_value()] is an |
| 3594 | ** [unprotected sqlite3_value] object. An unprotected sqlite3_value object |
| 3595 | ** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()]. |
| 3596 | ** If the [unprotected sqlite3_value] object returned by |
| 3597 | ** [sqlite3_column_value()] is used in any other way, including calls |
| 3598 | ** to routines like [sqlite3_value_int()], [sqlite3_value_text()], |
| 3599 | ** or [sqlite3_value_bytes()], then the behavior is undefined. |
| 3600 | ** |
| 3601 | ** These routines attempt to convert the value where appropriate. ^For |
| 3602 | ** example, if the internal representation is FLOAT and a text result |
| 3603 | ** is requested, [sqlite3_snprintf()] is used internally to perform the |
| 3604 | ** conversion automatically. ^(The following table details the conversions |
| 3605 | ** that are applied: |
| 3606 | ** |
| 3607 | ** <blockquote> |
| 3608 | ** <table border="1"> |
| 3609 | ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion |
| 3610 | ** |
| 3611 | ** <tr><td> NULL <td> INTEGER <td> Result is 0 |
| 3612 | ** <tr><td> NULL <td> FLOAT <td> Result is 0.0 |
| 3613 | ** <tr><td> NULL <td> TEXT <td> Result is NULL pointer |
| 3614 | ** <tr><td> NULL <td> BLOB <td> Result is NULL pointer |
| 3615 | ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float |
| 3616 | ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer |
| 3617 | ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT |
| 3618 | ** <tr><td> FLOAT <td> INTEGER <td> Convert from float to integer |
| 3619 | ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float |
| 3620 | ** <tr><td> FLOAT <td> BLOB <td> Same as FLOAT->TEXT |
| 3621 | ** <tr><td> TEXT <td> INTEGER <td> Use atoi() |
| 3622 | ** <tr><td> TEXT <td> FLOAT <td> Use atof() |
| 3623 | ** <tr><td> TEXT <td> BLOB <td> No change |
| 3624 | ** <tr><td> BLOB <td> INTEGER <td> Convert to TEXT then use atoi() |
| 3625 | ** <tr><td> BLOB <td> FLOAT <td> Convert to TEXT then use atof() |
| 3626 | ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed |
| 3627 | ** </table> |
| 3628 | ** </blockquote>)^ |
| 3629 | ** |
| 3630 | ** The table above makes reference to standard C library functions atoi() |
| 3631 | ** and atof(). SQLite does not really use these functions. It has its |
| 3632 | ** own equivalent internal routines. The atoi() and atof() names are |
| 3633 | ** used in the table for brevity and because they are familiar to most |
| 3634 | ** C programmers. |
| 3635 | ** |
| 3636 | ** Note that when type conversions occur, pointers returned by prior |
| 3637 | ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or |
| 3638 | ** sqlite3_column_text16() may be invalidated. |
| 3639 | ** Type conversions and pointer invalidations might occur |
| 3640 | ** in the following cases: |
| 3641 | ** |
| 3642 | ** <ul> |
| 3643 | ** <li> The initial content is a BLOB and sqlite3_column_text() or |
| 3644 | ** sqlite3_column_text16() is called. A zero-terminator might |
| 3645 | ** need to be added to the string.</li> |
| 3646 | ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or |
| 3647 | ** sqlite3_column_text16() is called. The content must be converted |
| 3648 | ** to UTF-16.</li> |
| 3649 | ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or |
| 3650 | ** sqlite3_column_text() is called. The content must be converted |
| 3651 | ** to UTF-8.</li> |
| 3652 | ** </ul> |
| 3653 | ** |
| 3654 | ** ^Conversions between UTF-16be and UTF-16le are always done in place and do |
| 3655 | ** not invalidate a prior pointer, though of course the content of the buffer |
| 3656 | ** that the prior pointer references will have been modified. Other kinds |
| 3657 | ** of conversion are done in place when it is possible, but sometimes they |
| 3658 | ** are not possible and in those cases prior pointers are invalidated. |
| 3659 | ** |
| 3660 | ** The safest and easiest to remember policy is to invoke these routines |
| 3661 | ** in one of the following ways: |
| 3662 | ** |
| 3663 | ** <ul> |
| 3664 | ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li> |
| 3665 | ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li> |
| 3666 | ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li> |
| 3667 | ** </ul> |
| 3668 | ** |
| 3669 | ** In other words, you should call sqlite3_column_text(), |
| 3670 | ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result |
| 3671 | ** into the desired format, then invoke sqlite3_column_bytes() or |
| 3672 | ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls |
| 3673 | ** to sqlite3_column_text() or sqlite3_column_blob() with calls to |
| 3674 | ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16() |
| 3675 | ** with calls to sqlite3_column_bytes(). |
| 3676 | ** |
| 3677 | ** ^The pointers returned are valid until a type conversion occurs as |
| 3678 | ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or |
| 3679 | ** [sqlite3_finalize()] is called. ^The memory space used to hold strings |
| 3680 | ** and BLOBs is freed automatically. Do <b>not</b> pass the pointers returned |
| 3681 | ** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into |
| 3682 | ** [sqlite3_free()]. |
| 3683 | ** |
| 3684 | ** ^(If a memory allocation error occurs during the evaluation of any |
| 3685 | ** of these routines, a default value is returned. The default value |
| 3686 | ** is either the integer 0, the floating point number 0.0, or a NULL |
| 3687 | ** pointer. Subsequent calls to [sqlite3_errcode()] will return |
| 3688 | ** [SQLITE_NOMEM].)^ |
| 3689 | */ |
| 3690 | SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); |
| 3691 | SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol); |
| 3692 | SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol); |
| 3693 | SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol); |
| 3694 | SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol); |
| 3695 | SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); |
| 3696 | SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol); |
| 3697 | SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol); |
| 3698 | SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol); |
| 3699 | SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol); |
| 3700 | |
| 3701 | /* |
| 3702 | ** CAPI3REF: Destroy A Prepared Statement Object |
| 3703 | ** |
| 3704 | ** ^The sqlite3_finalize() function is called to delete a [prepared statement]. |
| 3705 | ** ^If the most recent evaluation of the statement encountered no errors |
| 3706 | ** or if the statement is never been evaluated, then sqlite3_finalize() returns |
| 3707 | ** SQLITE_OK. ^If the most recent evaluation of statement S failed, then |
| 3708 | ** sqlite3_finalize(S) returns the appropriate [error code] or |
| 3709 | ** [extended error code]. |
| 3710 | ** |
| 3711 | ** ^The sqlite3_finalize(S) routine can be called at any point during |
| 3712 | ** the life cycle of [prepared statement] S: |
| 3713 | ** before statement S is ever evaluated, after |
| 3714 | ** one or more calls to [sqlite3_reset()], or after any call |
| 3715 | ** to [sqlite3_step()] regardless of whether or not the statement has |
| 3716 | ** completed execution. |
| 3717 | ** |
| 3718 | ** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op. |
| 3719 | ** |
| 3720 | ** The application must finalize every [prepared statement] in order to avoid |
| 3721 | ** resource leaks. It is a grievous error for the application to try to use |
| 3722 | ** a prepared statement after it has been finalized. Any use of a prepared |
| 3723 | ** statement after it has been finalized can result in undefined and |
| 3724 | ** undesirable behavior such as segfaults and heap corruption. |
| 3725 | */ |
| 3726 | SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt); |
| 3727 | |
| 3728 | /* |
| 3729 | ** CAPI3REF: Reset A Prepared Statement Object |
| 3730 | ** |
| 3731 | ** The sqlite3_reset() function is called to reset a [prepared statement] |
| 3732 | ** object back to its initial state, ready to be re-executed. |
| 3733 | ** ^Any SQL statement variables that had values bound to them using |
| 3734 | ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. |
| 3735 | ** Use [sqlite3_clear_bindings()] to reset the bindings. |
| 3736 | ** |
| 3737 | ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S |
| 3738 | ** back to the beginning of its program. |
| 3739 | ** |
| 3740 | ** ^If the most recent call to [sqlite3_step(S)] for the |
| 3741 | ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE], |
| 3742 | ** or if [sqlite3_step(S)] has never before been called on S, |
| 3743 | ** then [sqlite3_reset(S)] returns [SQLITE_OK]. |
| 3744 | ** |
| 3745 | ** ^If the most recent call to [sqlite3_step(S)] for the |
| 3746 | ** [prepared statement] S indicated an error, then |
| 3747 | ** [sqlite3_reset(S)] returns an appropriate [error code]. |
| 3748 | ** |
| 3749 | ** ^The [sqlite3_reset(S)] interface does not change the values |
| 3750 | ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S. |
| 3751 | */ |
| 3752 | SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt); |
| 3753 | |
| 3754 | /* |
| 3755 | ** CAPI3REF: Create Or Redefine SQL Functions |
| 3756 | ** KEYWORDS: {function creation routines} |
| 3757 | ** KEYWORDS: {application-defined SQL function} |
| 3758 | ** KEYWORDS: {application-defined SQL functions} |
| 3759 | ** |
| 3760 | ** ^These functions (collectively known as "function creation routines") |
| 3761 | ** are used to add SQL functions or aggregates or to redefine the behavior |
| 3762 | ** of existing SQL functions or aggregates. The only differences between |
| 3763 | ** these routines are the text encoding expected for |
| 3764 | ** the second parameter (the name of the function being created) |
| 3765 | ** and the presence or absence of a destructor callback for |
| 3766 | ** the application data pointer. |
| 3767 | ** |
| 3768 | ** ^The first parameter is the [database connection] to which the SQL |
| 3769 | ** function is to be added. ^If an application uses more than one database |
| 3770 | ** connection then application-defined SQL functions must be added |
| 3771 | ** to each database connection separately. |
| 3772 | ** |
| 3773 | ** ^The second parameter is the name of the SQL function to be created or |
| 3774 | ** redefined. ^The length of the name is limited to 255 bytes in a UTF-8 |
| 3775 | ** representation, exclusive of the zero-terminator. ^Note that the name |
| 3776 | ** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes. |
| 3777 | ** ^Any attempt to create a function with a longer name |
| 3778 | ** will result in [SQLITE_MISUSE] being returned. |
| 3779 | ** |
| 3780 | ** ^The third parameter (nArg) |
| 3781 | ** is the number of arguments that the SQL function or |
| 3782 | ** aggregate takes. ^If this parameter is -1, then the SQL function or |
| 3783 | ** aggregate may take any number of arguments between 0 and the limit |
| 3784 | ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third |
| 3785 | ** parameter is less than -1 or greater than 127 then the behavior is |
| 3786 | ** undefined. |
| 3787 | ** |
| 3788 | ** ^The fourth parameter, eTextRep, specifies what |
| 3789 | ** [SQLITE_UTF8 | text encoding] this SQL function prefers for |
| 3790 | ** its parameters. Every SQL function implementation must be able to work |
| 3791 | ** with UTF-8, UTF-16le, or UTF-16be. But some implementations may be |
| 3792 | ** more efficient with one encoding than another. ^An application may |
| 3793 | ** invoke sqlite3_create_function() or sqlite3_create_function16() multiple |
| 3794 | ** times with the same function but with different values of eTextRep. |
| 3795 | ** ^When multiple implementations of the same function are available, SQLite |
| 3796 | ** will pick the one that involves the least amount of data conversion. |
| 3797 | ** If there is only a single implementation which does not care what text |
| 3798 | ** encoding is used, then the fourth argument should be [SQLITE_ANY]. |
| 3799 | ** |
| 3800 | ** ^(The fifth parameter is an arbitrary pointer. The implementation of the |
| 3801 | ** function can gain access to this pointer using [sqlite3_user_data()].)^ |
| 3802 | ** |
| 3803 | ** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are |
| 3804 | ** pointers to C-language functions that implement the SQL function or |
| 3805 | ** aggregate. ^A scalar SQL function requires an implementation of the xFunc |
| 3806 | ** callback only; NULL pointers must be passed as the xStep and xFinal |
| 3807 | ** parameters. ^An aggregate SQL function requires an implementation of xStep |
| 3808 | ** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing |
| 3809 | ** SQL function or aggregate, pass NULL pointers for all three function |
| 3810 | ** callbacks. |
| 3811 | ** |
| 3812 | ** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL, |
| 3813 | ** then it is destructor for the application data pointer. |
| 3814 | ** The destructor is invoked when the function is deleted, either by being |
| 3815 | ** overloaded or when the database connection closes.)^ |
| 3816 | ** ^The destructor is also invoked if the call to |
| 3817 | ** sqlite3_create_function_v2() fails. |
| 3818 | ** ^When the destructor callback of the tenth parameter is invoked, it |
| 3819 | ** is passed a single argument which is a copy of the application data |
| 3820 | ** pointer which was the fifth parameter to sqlite3_create_function_v2(). |
| 3821 | ** |
| 3822 | ** ^It is permitted to register multiple implementations of the same |
| 3823 | ** functions with the same name but with either differing numbers of |
| 3824 | ** arguments or differing preferred text encodings. ^SQLite will use |
| 3825 | ** the implementation that most closely matches the way in which the |
| 3826 | ** SQL function is used. ^A function implementation with a non-negative |
| 3827 | ** nArg parameter is a better match than a function implementation with |
| 3828 | ** a negative nArg. ^A function where the preferred text encoding |
| 3829 | ** matches the database encoding is a better |
| 3830 | ** match than a function where the encoding is different. |
| 3831 | ** ^A function where the encoding difference is between UTF16le and UTF16be |
| 3832 | ** is a closer match than a function where the encoding difference is |
| 3833 | ** between UTF8 and UTF16. |
| 3834 | ** |
| 3835 | ** ^Built-in functions may be overloaded by new application-defined functions. |
| 3836 | ** |
| 3837 | ** ^An application-defined function is permitted to call other |
| 3838 | ** SQLite interfaces. However, such calls must not |
| 3839 | ** close the database connection nor finalize or reset the prepared |
| 3840 | ** statement in which the function is running. |
| 3841 | */ |
| 3842 | SQLITE_API int sqlite3_create_function( |
| 3843 | sqlite3 *db, |
| 3844 | const char *zFunctionName, |
| 3845 | int nArg, |
| 3846 | int eTextRep, |
| 3847 | void *pApp, |
| 3848 | void (*xFunc)(sqlite3_context*,int,sqlite3_value**), |
| 3849 | void (*xStep)(sqlite3_context*,int,sqlite3_value**), |
| 3850 | void (*xFinal)(sqlite3_context*) |
| 3851 | ); |
| 3852 | SQLITE_API int sqlite3_create_function16( |
| 3853 | sqlite3 *db, |
| 3854 | const void *zFunctionName, |
| 3855 | int nArg, |
| 3856 | int eTextRep, |
| 3857 | void *pApp, |
| 3858 | void (*xFunc)(sqlite3_context*,int,sqlite3_value**), |
| 3859 | void (*xStep)(sqlite3_context*,int,sqlite3_value**), |
| 3860 | void (*xFinal)(sqlite3_context*) |
| 3861 | ); |
| 3862 | SQLITE_API int sqlite3_create_function_v2( |
| 3863 | sqlite3 *db, |
| 3864 | const char *zFunctionName, |
| 3865 | int nArg, |
| 3866 | int eTextRep, |
| 3867 | void *pApp, |
| 3868 | void (*xFunc)(sqlite3_context*,int,sqlite3_value**), |
| 3869 | void (*xStep)(sqlite3_context*,int,sqlite3_value**), |
| 3870 | void (*xFinal)(sqlite3_context*), |
| 3871 | void(*xDestroy)(void*) |
| 3872 | ); |
| 3873 | |
| 3874 | /* |
| 3875 | ** CAPI3REF: Text Encodings |
| 3876 | ** |
| 3877 | ** These constant define integer codes that represent the various |
| 3878 | ** text encodings supported by SQLite. |
| 3879 | */ |
| 3880 | #define SQLITE_UTF8 1 |
| 3881 | #define SQLITE_UTF16LE 2 |
| 3882 | #define SQLITE_UTF16BE 3 |
| 3883 | #define SQLITE_UTF16 4 /* Use native byte order */ |
| 3884 | #define SQLITE_ANY 5 /* sqlite3_create_function only */ |
| 3885 | #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ |
| 3886 | |
| 3887 | /* |
| 3888 | ** CAPI3REF: Deprecated Functions |
| 3889 | ** DEPRECATED |
| 3890 | ** |
| 3891 | ** These functions are [deprecated]. In order to maintain |
| 3892 | ** backwards compatibility with older code, these functions continue |
| 3893 | ** to be supported. However, new applications should avoid |
| 3894 | ** the use of these functions. To help encourage people to avoid |
| 3895 | ** using these functions, we are not going to tell you what they do. |
| 3896 | */ |
| 3897 | #ifndef SQLITE_OMIT_DEPRECATED |
| 3898 | SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*); |
| 3899 | SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*); |
| 3900 | SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*); |
| 3901 | SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void); |
| 3902 | SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void); |
| 3903 | SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64); |
| 3904 | #endif |
| 3905 | |
| 3906 | /* |
| 3907 | ** CAPI3REF: Obtaining SQL Function Parameter Values |
| 3908 | ** |
| 3909 | ** The C-language implementation of SQL functions and aggregates uses |
| 3910 | ** this set of interface routines to access the parameter values on |
| 3911 | ** the function or aggregate. |
| 3912 | ** |
| 3913 | ** The xFunc (for scalar functions) or xStep (for aggregates) parameters |
| 3914 | ** to [sqlite3_create_function()] and [sqlite3_create_function16()] |
| 3915 | ** define callbacks that implement the SQL functions and aggregates. |
| 3916 | ** The 3rd parameter to these callbacks is an array of pointers to |
| 3917 | ** [protected sqlite3_value] objects. There is one [sqlite3_value] object for |
| 3918 | ** each parameter to the SQL function. These routines are used to |
| 3919 | ** extract values from the [sqlite3_value] objects. |
| 3920 | ** |
| 3921 | ** These routines work only with [protected sqlite3_value] objects. |
| 3922 | ** Any attempt to use these routines on an [unprotected sqlite3_value] |
| 3923 | ** object results in undefined behavior. |
| 3924 | ** |
| 3925 | ** ^These routines work just like the corresponding [column access functions] |
| 3926 | ** except that these routines take a single [protected sqlite3_value] object |
| 3927 | ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number. |
| 3928 | ** |
| 3929 | ** ^The sqlite3_value_text16() interface extracts a UTF-16 string |
| 3930 | ** in the native byte-order of the host machine. ^The |
| 3931 | ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces |
| 3932 | ** extract UTF-16 strings as big-endian and little-endian respectively. |
| 3933 | ** |
| 3934 | ** ^(The sqlite3_value_numeric_type() interface attempts to apply |
| 3935 | ** numeric affinity to the value. This means that an attempt is |
| 3936 | ** made to convert the value to an integer or floating point. If |
| 3937 | ** such a conversion is possible without loss of information (in other |
| 3938 | ** words, if the value is a string that looks like a number) |
| 3939 | ** then the conversion is performed. Otherwise no conversion occurs. |
| 3940 | ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^ |
| 3941 | ** |
| 3942 | ** Please pay particular attention to the fact that the pointer returned |
| 3943 | ** from [sqlite3_value_blob()], [sqlite3_value_text()], or |
| 3944 | ** [sqlite3_value_text16()] can be invalidated by a subsequent call to |
| 3945 | ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], |
| 3946 | ** or [sqlite3_value_text16()]. |
| 3947 | ** |
| 3948 | ** These routines must be called from the same thread as |
| 3949 | ** the SQL function that supplied the [sqlite3_value*] parameters. |
| 3950 | */ |
| 3951 | SQLITE_API const void *sqlite3_value_blob(sqlite3_value*); |
| 3952 | SQLITE_API int sqlite3_value_bytes(sqlite3_value*); |
| 3953 | SQLITE_API int sqlite3_value_bytes16(sqlite3_value*); |
| 3954 | SQLITE_API double sqlite3_value_double(sqlite3_value*); |
| 3955 | SQLITE_API int sqlite3_value_int(sqlite3_value*); |
| 3956 | SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*); |
| 3957 | SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*); |
| 3958 | SQLITE_API const void *sqlite3_value_text16(sqlite3_value*); |
| 3959 | SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*); |
| 3960 | SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*); |
| 3961 | SQLITE_API int sqlite3_value_type(sqlite3_value*); |
| 3962 | SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*); |
| 3963 | |
| 3964 | /* |
| 3965 | ** CAPI3REF: Obtain Aggregate Function Context |
| 3966 | ** |
| 3967 | ** Implementations of aggregate SQL functions use this |
| 3968 | ** routine to allocate memory for storing their state. |
| 3969 | ** |
| 3970 | ** ^The first time the sqlite3_aggregate_context(C,N) routine is called |
| 3971 | ** for a particular aggregate function, SQLite |
| 3972 | ** allocates N of memory, zeroes out that memory, and returns a pointer |
| 3973 | ** to the new memory. ^On second and subsequent calls to |
| 3974 | ** sqlite3_aggregate_context() for the same aggregate function instance, |
| 3975 | ** the same buffer is returned. Sqlite3_aggregate_context() is normally |
| 3976 | ** called once for each invocation of the xStep callback and then one |
| 3977 | ** last time when the xFinal callback is invoked. ^(When no rows match |
| 3978 | ** an aggregate query, the xStep() callback of the aggregate function |
| 3979 | ** implementation is never called and xFinal() is called exactly once. |
| 3980 | ** In those cases, sqlite3_aggregate_context() might be called for the |
| 3981 | ** first time from within xFinal().)^ |
| 3982 | ** |
| 3983 | ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer if N is |
| 3984 | ** less than or equal to zero or if a memory allocate error occurs. |
| 3985 | ** |
| 3986 | ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is |
| 3987 | ** determined by the N parameter on first successful call. Changing the |
| 3988 | ** value of N in subsequent call to sqlite3_aggregate_context() within |
| 3989 | ** the same aggregate function instance will not resize the memory |
| 3990 | ** allocation.)^ |
| 3991 | ** |
| 3992 | ** ^SQLite automatically frees the memory allocated by |
| 3993 | ** sqlite3_aggregate_context() when the aggregate query concludes. |
| 3994 | ** |
| 3995 | ** The first parameter must be a copy of the |
| 3996 | ** [sqlite3_context | SQL function context] that is the first parameter |
| 3997 | ** to the xStep or xFinal callback routine that implements the aggregate |
| 3998 | ** function. |
| 3999 | ** |
| 4000 | ** This routine must be called from the same thread in which |
| 4001 | ** the aggregate SQL function is running. |
| 4002 | */ |
| 4003 | SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); |
| 4004 | |
| 4005 | /* |
| 4006 | ** CAPI3REF: User Data For Functions |
| 4007 | ** |
| 4008 | ** ^The sqlite3_user_data() interface returns a copy of |
| 4009 | ** the pointer that was the pUserData parameter (the 5th parameter) |
| 4010 | ** of the [sqlite3_create_function()] |
| 4011 | ** and [sqlite3_create_function16()] routines that originally |
| 4012 | ** registered the application defined function. |
| 4013 | ** |
| 4014 | ** This routine must be called from the same thread in which |
| 4015 | ** the application-defined function is running. |
| 4016 | */ |
| 4017 | SQLITE_API void *sqlite3_user_data(sqlite3_context*); |
| 4018 | |
| 4019 | /* |
| 4020 | ** CAPI3REF: Database Connection For Functions |
| 4021 | ** |
| 4022 | ** ^The sqlite3_context_db_handle() interface returns a copy of |
| 4023 | ** the pointer to the [database connection] (the 1st parameter) |
| 4024 | ** of the [sqlite3_create_function()] |
| 4025 | ** and [sqlite3_create_function16()] routines that originally |
| 4026 | ** registered the application defined function. |
| 4027 | */ |
| 4028 | SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*); |
| 4029 | |
| 4030 | /* |
| 4031 | ** CAPI3REF: Function Auxiliary Data |
| 4032 | ** |
| 4033 | ** The following two functions may be used by scalar SQL functions to |
| 4034 | ** associate metadata with argument values. If the same value is passed to |
| 4035 | ** multiple invocations of the same SQL function during query execution, under |
| 4036 | ** some circumstances the associated metadata may be preserved. This may |
| 4037 | ** be used, for example, to add a regular-expression matching scalar |
| 4038 | ** function. The compiled version of the regular expression is stored as |
| 4039 | ** metadata associated with the SQL value passed as the regular expression |
| 4040 | ** pattern. The compiled regular expression can be reused on multiple |
| 4041 | ** invocations of the same function so that the original pattern string |
| 4042 | ** does not need to be recompiled on each invocation. |
| 4043 | ** |
| 4044 | ** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata |
| 4045 | ** associated by the sqlite3_set_auxdata() function with the Nth argument |
| 4046 | ** value to the application-defined function. ^If no metadata has been ever |
| 4047 | ** been set for the Nth argument of the function, or if the corresponding |
| 4048 | ** function parameter has changed since the meta-data was set, |
| 4049 | ** then sqlite3_get_auxdata() returns a NULL pointer. |
| 4050 | ** |
| 4051 | ** ^The sqlite3_set_auxdata() interface saves the metadata |
| 4052 | ** pointed to by its 3rd parameter as the metadata for the N-th |
| 4053 | ** argument of the application-defined function. Subsequent |
| 4054 | ** calls to sqlite3_get_auxdata() might return this data, if it has |
| 4055 | ** not been destroyed. |
| 4056 | ** ^If it is not NULL, SQLite will invoke the destructor |
| 4057 | ** function given by the 4th parameter to sqlite3_set_auxdata() on |
| 4058 | ** the metadata when the corresponding function parameter changes |
| 4059 | ** or when the SQL statement completes, whichever comes first. |
| 4060 | ** |
| 4061 | ** SQLite is free to call the destructor and drop metadata on any |
| 4062 | ** parameter of any function at any time. ^The only guarantee is that |
| 4063 | ** the destructor will be called before the metadata is dropped. |
| 4064 | ** |
| 4065 | ** ^(In practice, metadata is preserved between function calls for |
| 4066 | ** expressions that are constant at compile time. This includes literal |
| 4067 | ** values and [parameters].)^ |
| 4068 | ** |
| 4069 | ** These routines must be called from the same thread in which |
| 4070 | ** the SQL function is running. |
| 4071 | */ |
| 4072 | SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N); |
| 4073 | SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*)); |
| 4074 | |
| 4075 | |
| 4076 | /* |
| 4077 | ** CAPI3REF: Constants Defining Special Destructor Behavior |
| 4078 | ** |
| 4079 | ** These are special values for the destructor that is passed in as the |
| 4080 | ** final argument to routines like [sqlite3_result_blob()]. ^If the destructor |
| 4081 | ** argument is SQLITE_STATIC, it means that the content pointer is constant |
| 4082 | ** and will never change. It does not need to be destroyed. ^The |
| 4083 | ** SQLITE_TRANSIENT value means that the content will likely change in |
| 4084 | ** the near future and that SQLite should make its own private copy of |
| 4085 | ** the content before returning. |
| 4086 | ** |
| 4087 | ** The typedef is necessary to work around problems in certain |
| 4088 | ** C++ compilers. See ticket #2191. |
| 4089 | */ |
| 4090 | typedef void (*sqlite3_destructor_type)(void*); |
| 4091 | #define SQLITE_STATIC ((sqlite3_destructor_type)0) |
| 4092 | #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) |
| 4093 | |
| 4094 | /* |
| 4095 | ** CAPI3REF: Setting The Result Of An SQL Function |
| 4096 | ** |
| 4097 | ** These routines are used by the xFunc or xFinal callbacks that |
| 4098 | ** implement SQL functions and aggregates. See |
| 4099 | ** [sqlite3_create_function()] and [sqlite3_create_function16()] |
| 4100 | ** for additional information. |
| 4101 | ** |
| 4102 | ** These functions work very much like the [parameter binding] family of |
| 4103 | ** functions used to bind values to host parameters in prepared statements. |
| 4104 | ** Refer to the [SQL parameter] documentation for additional information. |
| 4105 | ** |
| 4106 | ** ^The sqlite3_result_blob() interface sets the result from |
| 4107 | ** an application-defined function to be the BLOB whose content is pointed |
| 4108 | ** to by the second parameter and which is N bytes long where N is the |
| 4109 | ** third parameter. |
| 4110 | ** |
| 4111 | ** ^The sqlite3_result_zeroblob() interfaces set the result of |
| 4112 | ** the application-defined function to be a BLOB containing all zero |
| 4113 | ** bytes and N bytes in size, where N is the value of the 2nd parameter. |
| 4114 | ** |
| 4115 | ** ^The sqlite3_result_double() interface sets the result from |
| 4116 | ** an application-defined function to be a floating point value specified |
| 4117 | ** by its 2nd argument. |
| 4118 | ** |
| 4119 | ** ^The sqlite3_result_error() and sqlite3_result_error16() functions |
| 4120 | ** cause the implemented SQL function to throw an exception. |
| 4121 | ** ^SQLite uses the string pointed to by the |
| 4122 | ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() |
| 4123 | ** as the text of an error message. ^SQLite interprets the error |
| 4124 | ** message string from sqlite3_result_error() as UTF-8. ^SQLite |
| 4125 | ** interprets the string from sqlite3_result_error16() as UTF-16 in native |
| 4126 | ** byte order. ^If the third parameter to sqlite3_result_error() |
| 4127 | ** or sqlite3_result_error16() is negative then SQLite takes as the error |
| 4128 | ** message all text up through the first zero character. |
| 4129 | ** ^If the third parameter to sqlite3_result_error() or |
| 4130 | ** sqlite3_result_error16() is non-negative then SQLite takes that many |
| 4131 | ** bytes (not characters) from the 2nd parameter as the error message. |
| 4132 | ** ^The sqlite3_result_error() and sqlite3_result_error16() |
| 4133 | ** routines make a private copy of the error message text before |
| 4134 | ** they return. Hence, the calling function can deallocate or |
| 4135 | ** modify the text after they return without harm. |
| 4136 | ** ^The sqlite3_result_error_code() function changes the error code |
| 4137 | ** returned by SQLite as a result of an error in a function. ^By default, |
| 4138 | ** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error() |
| 4139 | ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR. |
| 4140 | ** |
| 4141 | ** ^The sqlite3_result_toobig() interface causes SQLite to throw an error |
| 4142 | ** indicating that a string or BLOB is too long to represent. |
| 4143 | ** |
| 4144 | ** ^The sqlite3_result_nomem() interface causes SQLite to throw an error |
| 4145 | ** indicating that a memory allocation failed. |
| 4146 | ** |
| 4147 | ** ^The sqlite3_result_int() interface sets the return value |
| 4148 | ** of the application-defined function to be the 32-bit signed integer |
| 4149 | ** value given in the 2nd argument. |
| 4150 | ** ^The sqlite3_result_int64() interface sets the return value |
| 4151 | ** of the application-defined function to be the 64-bit signed integer |
| 4152 | ** value given in the 2nd argument. |
| 4153 | ** |
| 4154 | ** ^The sqlite3_result_null() interface sets the return value |
| 4155 | ** of the application-defined function to be NULL. |
| 4156 | ** |
| 4157 | ** ^The sqlite3_result_text(), sqlite3_result_text16(), |
| 4158 | ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces |
| 4159 | ** set the return value of the application-defined function to be |
| 4160 | ** a text string which is represented as UTF-8, UTF-16 native byte order, |
| 4161 | ** UTF-16 little endian, or UTF-16 big endian, respectively. |
| 4162 | ** ^SQLite takes the text result from the application from |
| 4163 | ** the 2nd parameter of the sqlite3_result_text* interfaces. |
| 4164 | ** ^If the 3rd parameter to the sqlite3_result_text* interfaces |
| 4165 | ** is negative, then SQLite takes result text from the 2nd parameter |
| 4166 | ** through the first zero character. |
| 4167 | ** ^If the 3rd parameter to the sqlite3_result_text* interfaces |
| 4168 | ** is non-negative, then as many bytes (not characters) of the text |
| 4169 | ** pointed to by the 2nd parameter are taken as the application-defined |
| 4170 | ** function result. If the 3rd parameter is non-negative, then it |
| 4171 | ** must be the byte offset into the string where the NUL terminator would |
| 4172 | ** appear if the string where NUL terminated. If any NUL characters occur |
| 4173 | ** in the string at a byte offset that is less than the value of the 3rd |
| 4174 | ** parameter, then the resulting string will contain embedded NULs and the |
| 4175 | ** result of expressions operating on strings with embedded NULs is undefined. |
| 4176 | ** ^If the 4th parameter to the sqlite3_result_text* interfaces |
| 4177 | ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that |
| 4178 | ** function as the destructor on the text or BLOB result when it has |
| 4179 | ** finished using that result. |
| 4180 | ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to |
| 4181 | ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite |
| 4182 | ** assumes that the text or BLOB result is in constant space and does not |
| 4183 | ** copy the content of the parameter nor call a destructor on the content |
| 4184 | ** when it has finished using that result. |
| 4185 | ** ^If the 4th parameter to the sqlite3_result_text* interfaces |
| 4186 | ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT |
| 4187 | ** then SQLite makes a copy of the result into space obtained from |
| 4188 | ** from [sqlite3_malloc()] before it returns. |
| 4189 | ** |
| 4190 | ** ^The sqlite3_result_value() interface sets the result of |
| 4191 | ** the application-defined function to be a copy the |
| 4192 | ** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The |
| 4193 | ** sqlite3_result_value() interface makes a copy of the [sqlite3_value] |
| 4194 | ** so that the [sqlite3_value] specified in the parameter may change or |
| 4195 | ** be deallocated after sqlite3_result_value() returns without harm. |
| 4196 | ** ^A [protected sqlite3_value] object may always be used where an |
| 4197 | ** [unprotected sqlite3_value] object is required, so either |
| 4198 | ** kind of [sqlite3_value] object can be used with this interface. |
| 4199 | ** |
| 4200 | ** If these routines are called from within the different thread |
| 4201 | ** than the one containing the application-defined function that received |
| 4202 | ** the [sqlite3_context] pointer, the results are undefined. |
| 4203 | */ |
| 4204 | SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*)); |
| 4205 | SQLITE_API void sqlite3_result_double(sqlite3_context*, double); |
| 4206 | SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int); |
| 4207 | SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int); |
| 4208 | SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*); |
| 4209 | SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*); |
| 4210 | SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int); |
| 4211 | SQLITE_API void sqlite3_result_int(sqlite3_context*, int); |
| 4212 | SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64); |
| 4213 | SQLITE_API void sqlite3_result_null(sqlite3_context*); |
| 4214 | SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*)); |
| 4215 | SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*)); |
| 4216 | SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*)); |
| 4217 | SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*)); |
| 4218 | SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*); |
| 4219 | SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n); |
| 4220 | |
| 4221 | /* |
| 4222 | ** CAPI3REF: Define New Collating Sequences |
| 4223 | ** |
| 4224 | ** ^These functions add, remove, or modify a [collation] associated |
| 4225 | ** with the [database connection] specified as the first argument. |
| 4226 | ** |
| 4227 | ** ^The name of the collation is a UTF-8 string |
| 4228 | ** for sqlite3_create_collation() and sqlite3_create_collation_v2() |
| 4229 | ** and a UTF-16 string in native byte order for sqlite3_create_collation16(). |
| 4230 | ** ^Collation names that compare equal according to [sqlite3_strnicmp()] are |
| 4231 | ** considered to be the same name. |
| 4232 | ** |
| 4233 | ** ^(The third argument (eTextRep) must be one of the constants: |
| 4234 | ** <ul> |
| 4235 | ** <li> [SQLITE_UTF8], |
| 4236 | ** <li> [SQLITE_UTF16LE], |
| 4237 | ** <li> [SQLITE_UTF16BE], |
| 4238 | ** <li> [SQLITE_UTF16], or |
| 4239 | ** <li> [SQLITE_UTF16_ALIGNED]. |
| 4240 | ** </ul>)^ |
| 4241 | ** ^The eTextRep argument determines the encoding of strings passed |
| 4242 | ** to the collating function callback, xCallback. |
| 4243 | ** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep |
| 4244 | ** force strings to be UTF16 with native byte order. |
| 4245 | ** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin |
| 4246 | ** on an even byte address. |
| 4247 | ** |
| 4248 | ** ^The fourth argument, pArg, is an application data pointer that is passed |
| 4249 | ** through as the first argument to the collating function callback. |
| 4250 | ** |
| 4251 | ** ^The fifth argument, xCallback, is a pointer to the collating function. |
| 4252 | ** ^Multiple collating functions can be registered using the same name but |
| 4253 | ** with different eTextRep parameters and SQLite will use whichever |
| 4254 | ** function requires the least amount of data transformation. |
| 4255 | ** ^If the xCallback argument is NULL then the collating function is |
| 4256 | ** deleted. ^When all collating functions having the same name are deleted, |
| 4257 | ** that collation is no longer usable. |
| 4258 | ** |
| 4259 | ** ^The collating function callback is invoked with a copy of the pArg |
| 4260 | ** application data pointer and with two strings in the encoding specified |
| 4261 | ** by the eTextRep argument. The collating function must return an |
| 4262 | ** integer that is negative, zero, or positive |
| 4263 | ** if the first string is less than, equal to, or greater than the second, |
| 4264 | ** respectively. A collating function must always return the same answer |
| 4265 | ** given the same inputs. If two or more collating functions are registered |
| 4266 | ** to the same collation name (using different eTextRep values) then all |
| 4267 | ** must give an equivalent answer when invoked with equivalent strings. |
| 4268 | ** The collating function must obey the following properties for all |
| 4269 | ** strings A, B, and C: |
| 4270 | ** |
| 4271 | ** <ol> |
| 4272 | ** <li> If A==B then B==A. |
| 4273 | ** <li> If A==B and B==C then A==C. |
| 4274 | ** <li> If A<B THEN B>A. |
| 4275 | ** <li> If A<B and B<C then A<C. |
| 4276 | ** </ol> |
| 4277 | ** |
| 4278 | ** If a collating function fails any of the above constraints and that |
| 4279 | ** collating function is registered and used, then the behavior of SQLite |
| 4280 | ** is undefined. |
| 4281 | ** |
| 4282 | ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation() |
| 4283 | ** with the addition that the xDestroy callback is invoked on pArg when |
| 4284 | ** the collating function is deleted. |
| 4285 | ** ^Collating functions are deleted when they are overridden by later |
| 4286 | ** calls to the collation creation functions or when the |
| 4287 | ** [database connection] is closed using [sqlite3_close()]. |
| 4288 | ** |
| 4289 | ** ^The xDestroy callback is <u>not</u> called if the |
| 4290 | ** sqlite3_create_collation_v2() function fails. Applications that invoke |
| 4291 | ** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should |
| 4292 | ** check the return code and dispose of the application data pointer |
| 4293 | ** themselves rather than expecting SQLite to deal with it for them. |
| 4294 | ** This is different from every other SQLite interface. The inconsistency |
| 4295 | ** is unfortunate but cannot be changed without breaking backwards |
| 4296 | ** compatibility. |
| 4297 | ** |
| 4298 | ** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()]. |
| 4299 | */ |
| 4300 | SQLITE_API int sqlite3_create_collation( |
| 4301 | sqlite3*, |
| 4302 | const char *zName, |
| 4303 | int eTextRep, |
| 4304 | void *pArg, |
| 4305 | int(*xCompare)(void*,int,const void*,int,const void*) |
| 4306 | ); |
| 4307 | SQLITE_API int sqlite3_create_collation_v2( |
| 4308 | sqlite3*, |
| 4309 | const char *zName, |
| 4310 | int eTextRep, |
| 4311 | void *pArg, |
| 4312 | int(*xCompare)(void*,int,const void*,int,const void*), |
| 4313 | void(*xDestroy)(void*) |
| 4314 | ); |
| 4315 | SQLITE_API int sqlite3_create_collation16( |
| 4316 | sqlite3*, |
| 4317 | const void *zName, |
| 4318 | int eTextRep, |
| 4319 | void *pArg, |
| 4320 | int(*xCompare)(void*,int,const void*,int,const void*) |
| 4321 | ); |
| 4322 | |
| 4323 | /* |
| 4324 | ** CAPI3REF: Collation Needed Callbacks |
| 4325 | ** |
| 4326 | ** ^To avoid having to register all collation sequences before a database |
| 4327 | ** can be used, a single callback function may be registered with the |
| 4328 | ** [database connection] to be invoked whenever an undefined collation |
| 4329 | ** sequence is required. |
| 4330 | ** |
| 4331 | ** ^If the function is registered using the sqlite3_collation_needed() API, |
| 4332 | ** then it is passed the names of undefined collation sequences as strings |
| 4333 | ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used, |
| 4334 | ** the names are passed as UTF-16 in machine native byte order. |
| 4335 | ** ^A call to either function replaces the existing collation-needed callback. |
| 4336 | ** |
| 4337 | ** ^(When the callback is invoked, the first argument passed is a copy |
| 4338 | ** of the second argument to sqlite3_collation_needed() or |
| 4339 | ** sqlite3_collation_needed16(). The second argument is the database |
| 4340 | ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], |
| 4341 | ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation |
| 4342 | ** sequence function required. The fourth parameter is the name of the |
| 4343 | ** required collation sequence.)^ |
| 4344 | ** |
| 4345 | ** The callback function should register the desired collation using |
| 4346 | ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or |
| 4347 | ** [sqlite3_create_collation_v2()]. |
| 4348 | */ |
| 4349 | SQLITE_API int sqlite3_collation_needed( |
| 4350 | sqlite3*, |
| 4351 | void*, |
| 4352 | void(*)(void*,sqlite3*,int eTextRep,const char*) |
| 4353 | ); |
| 4354 | SQLITE_API int sqlite3_collation_needed16( |
| 4355 | sqlite3*, |
| 4356 | void*, |
| 4357 | void(*)(void*,sqlite3*,int eTextRep,const void*) |
| 4358 | ); |
| 4359 | |
| 4360 | #ifdef SQLITE_HAS_CODEC |
| 4361 | /* |
| 4362 | ** Specify the key for an encrypted database. This routine should be |
| 4363 | ** called right after sqlite3_open(). |
| 4364 | ** |
| 4365 | ** The code to implement this API is not available in the public release |
| 4366 | ** of SQLite. |
| 4367 | */ |
| 4368 | SQLITE_API int sqlite3_key( |
| 4369 | sqlite3 *db, /* Database to be rekeyed */ |
| 4370 | const void *pKey, int nKey /* The key */ |
| 4371 | ); |
| 4372 | |
| 4373 | /* |
| 4374 | ** Change the key on an open database. If the current database is not |
| 4375 | ** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the |
| 4376 | ** database is decrypted. |
| 4377 | ** |
| 4378 | ** The code to implement this API is not available in the public release |
| 4379 | ** of SQLite. |
| 4380 | */ |
| 4381 | SQLITE_API int sqlite3_rekey( |
| 4382 | sqlite3 *db, /* Database to be rekeyed */ |
| 4383 | const void *pKey, int nKey /* The new key */ |
| 4384 | ); |
| 4385 | |
| 4386 | /* |
| 4387 | ** Specify the activation key for a SEE database. Unless |
| 4388 | ** activated, none of the SEE routines will work. |
| 4389 | */ |
| 4390 | SQLITE_API void sqlite3_activate_see( |
| 4391 | const char *zPassPhrase /* Activation phrase */ |
| 4392 | ); |
| 4393 | #endif |
| 4394 | |
| 4395 | #ifdef SQLITE_ENABLE_CEROD |
| 4396 | /* |
| 4397 | ** Specify the activation key for a CEROD database. Unless |
| 4398 | ** activated, none of the CEROD routines will work. |
| 4399 | */ |
| 4400 | SQLITE_API void sqlite3_activate_cerod( |
| 4401 | const char *zPassPhrase /* Activation phrase */ |
| 4402 | ); |
| 4403 | #endif |
| 4404 | |
| 4405 | /* |
| 4406 | ** CAPI3REF: Suspend Execution For A Short Time |
| 4407 | ** |
| 4408 | ** The sqlite3_sleep() function causes the current thread to suspend execution |
| 4409 | ** for at least a number of milliseconds specified in its parameter. |
| 4410 | ** |
| 4411 | ** If the operating system does not support sleep requests with |
| 4412 | ** millisecond time resolution, then the time will be rounded up to |
| 4413 | ** the nearest second. The number of milliseconds of sleep actually |
| 4414 | ** requested from the operating system is returned. |
| 4415 | ** |
| 4416 | ** ^SQLite implements this interface by calling the xSleep() |
| 4417 | ** method of the default [sqlite3_vfs] object. If the xSleep() method |
| 4418 | ** of the default VFS is not implemented correctly, or not implemented at |
| 4419 | ** all, then the behavior of sqlite3_sleep() may deviate from the description |
| 4420 | ** in the previous paragraphs. |
| 4421 | */ |
| 4422 | SQLITE_API int sqlite3_sleep(int); |
| 4423 | |
| 4424 | /* |
| 4425 | ** CAPI3REF: Name Of The Folder Holding Temporary Files |
| 4426 | ** |
| 4427 | ** ^(If this global variable is made to point to a string which is |
| 4428 | ** the name of a folder (a.k.a. directory), then all temporary files |
| 4429 | ** created by SQLite when using a built-in [sqlite3_vfs | VFS] |
| 4430 | ** will be placed in that directory.)^ ^If this variable |
| 4431 | ** is a NULL pointer, then SQLite performs a search for an appropriate |
| 4432 | ** temporary file directory. |
| 4433 | ** |
| 4434 | ** It is not safe to read or modify this variable in more than one |
| 4435 | ** thread at a time. It is not safe to read or modify this variable |
| 4436 | ** if a [database connection] is being used at the same time in a separate |
| 4437 | ** thread. |
| 4438 | ** It is intended that this variable be set once |
| 4439 | ** as part of process initialization and before any SQLite interface |
| 4440 | ** routines have been called and that this variable remain unchanged |
| 4441 | ** thereafter. |
| 4442 | ** |
| 4443 | ** ^The [temp_store_directory pragma] may modify this variable and cause |
| 4444 | ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, |
| 4445 | ** the [temp_store_directory pragma] always assumes that any string |
| 4446 | ** that this variable points to is held in memory obtained from |
| 4447 | ** [sqlite3_malloc] and the pragma may attempt to free that memory |
| 4448 | ** using [sqlite3_free]. |
| 4449 | ** Hence, if this variable is modified directly, either it should be |
| 4450 | ** made NULL or made to point to memory obtained from [sqlite3_malloc] |
| 4451 | ** or else the use of the [temp_store_directory pragma] should be avoided. |
| 4452 | */ |
| 4453 | SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory; |
| 4454 | |
| 4455 | /* |
| 4456 | ** CAPI3REF: Name Of The Folder Holding Database Files |
| 4457 | ** |
| 4458 | ** ^(If this global variable is made to point to a string which is |
| 4459 | ** the name of a folder (a.k.a. directory), then all database files |
| 4460 | ** specified with a relative pathname and created or accessed by |
| 4461 | ** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed |
| 4462 | ** to be relative to that directory.)^ ^If this variable is a NULL |
| 4463 | ** pointer, then SQLite assumes that all database files specified |
| 4464 | ** with a relative pathname are relative to the current directory |
| 4465 | ** for the process. Only the windows VFS makes use of this global |
| 4466 | ** variable; it is ignored by the unix VFS. |
| 4467 | ** |
| 4468 | ** Changing the value of this variable while a database connection is |
| 4469 | ** open can result in a corrupt database. |
| 4470 | ** |
| 4471 | ** It is not safe to read or modify this variable in more than one |
| 4472 | ** thread at a time. It is not safe to read or modify this variable |
| 4473 | ** if a [database connection] is being used at the same time in a separate |
| 4474 | ** thread. |
| 4475 | ** It is intended that this variable be set once |
| 4476 | ** as part of process initialization and before any SQLite interface |
| 4477 | ** routines have been called and that this variable remain unchanged |
| 4478 | ** thereafter. |
| 4479 | ** |
| 4480 | ** ^The [data_store_directory pragma] may modify this variable and cause |
| 4481 | ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, |
| 4482 | ** the [data_store_directory pragma] always assumes that any string |
| 4483 | ** that this variable points to is held in memory obtained from |
| 4484 | ** [sqlite3_malloc] and the pragma may attempt to free that memory |
| 4485 | ** using [sqlite3_free]. |
| 4486 | ** Hence, if this variable is modified directly, either it should be |
| 4487 | ** made NULL or made to point to memory obtained from [sqlite3_malloc] |
| 4488 | ** or else the use of the [data_store_directory pragma] should be avoided. |
| 4489 | */ |
| 4490 | SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory; |
| 4491 | |
| 4492 | /* |
| 4493 | ** CAPI3REF: Test For Auto-Commit Mode |
| 4494 | ** KEYWORDS: {autocommit mode} |
| 4495 | ** |
| 4496 | ** ^The sqlite3_get_autocommit() interface returns non-zero or |
| 4497 | ** zero if the given database connection is or is not in autocommit mode, |
| 4498 | ** respectively. ^Autocommit mode is on by default. |
| 4499 | ** ^Autocommit mode is disabled by a [BEGIN] statement. |
| 4500 | ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK]. |
| 4501 | ** |
| 4502 | ** If certain kinds of errors occur on a statement within a multi-statement |
| 4503 | ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR], |
| 4504 | ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the |
| 4505 | ** transaction might be rolled back automatically. The only way to |
| 4506 | ** find out whether SQLite automatically rolled back the transaction after |
| 4507 | ** an error is to use this function. |
| 4508 | ** |
| 4509 | ** If another thread changes the autocommit status of the database |
| 4510 | ** connection while this routine is running, then the return value |
| 4511 | ** is undefined. |
| 4512 | */ |
| 4513 | SQLITE_API int sqlite3_get_autocommit(sqlite3*); |
| 4514 | |
| 4515 | /* |
| 4516 | ** CAPI3REF: Find The Database Handle Of A Prepared Statement |
| 4517 | ** |
| 4518 | ** ^The sqlite3_db_handle interface returns the [database connection] handle |
| 4519 | ** to which a [prepared statement] belongs. ^The [database connection] |
| 4520 | ** returned by sqlite3_db_handle is the same [database connection] |
| 4521 | ** that was the first argument |
| 4522 | ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to |
| 4523 | ** create the statement in the first place. |
| 4524 | */ |
| 4525 | SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*); |
| 4526 | |
| 4527 | /* |
| 4528 | ** CAPI3REF: Return The Filename For A Database Connection |
| 4529 | ** |
| 4530 | ** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename |
| 4531 | ** associated with database N of connection D. ^The main database file |
| 4532 | ** has the name "main". If there is no attached database N on the database |
| 4533 | ** connection D, or if database N is a temporary or in-memory database, then |
| 4534 | ** a NULL pointer is returned. |
| 4535 | ** |
| 4536 | ** ^The filename returned by this function is the output of the |
| 4537 | ** xFullPathname method of the [VFS]. ^In other words, the filename |
| 4538 | ** will be an absolute pathname, even if the filename used |
| 4539 | ** to open the database originally was a URI or relative pathname. |
| 4540 | */ |
| 4541 | SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName); |
| 4542 | |
| 4543 | /* |
| 4544 | ** CAPI3REF: Determine if a database is read-only |
| 4545 | ** |
| 4546 | ** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N |
| 4547 | ** of connection D is read-only, 0 if it is read/write, or -1 if N is not |
| 4548 | ** the name of a database on connection D. |
| 4549 | */ |
| 4550 | SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName); |
| 4551 | |
| 4552 | /* |
| 4553 | ** CAPI3REF: Find the next prepared statement |
| 4554 | ** |
| 4555 | ** ^This interface returns a pointer to the next [prepared statement] after |
| 4556 | ** pStmt associated with the [database connection] pDb. ^If pStmt is NULL |
| 4557 | ** then this interface returns a pointer to the first prepared statement |
| 4558 | ** associated with the database connection pDb. ^If no prepared statement |
| 4559 | ** satisfies the conditions of this routine, it returns NULL. |
| 4560 | ** |
| 4561 | ** The [database connection] pointer D in a call to |
| 4562 | ** [sqlite3_next_stmt(D,S)] must refer to an open database |
| 4563 | ** connection and in particular must not be a NULL pointer. |
| 4564 | */ |
| 4565 | SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt); |
| 4566 | |
| 4567 | /* |
| 4568 | ** CAPI3REF: Commit And Rollback Notification Callbacks |
| 4569 | ** |
| 4570 | ** ^The sqlite3_commit_hook() interface registers a callback |
| 4571 | ** function to be invoked whenever a transaction is [COMMIT | committed]. |
| 4572 | ** ^Any callback set by a previous call to sqlite3_commit_hook() |
| 4573 | ** for the same database connection is overridden. |
| 4574 | ** ^The sqlite3_rollback_hook() interface registers a callback |
| 4575 | ** function to be invoked whenever a transaction is [ROLLBACK | rolled back]. |
| 4576 | ** ^Any callback set by a previous call to sqlite3_rollback_hook() |
| 4577 | ** for the same database connection is overridden. |
| 4578 | ** ^The pArg argument is passed through to the callback. |
| 4579 | ** ^If the callback on a commit hook function returns non-zero, |
| 4580 | ** then the commit is converted into a rollback. |
| 4581 | ** |
| 4582 | ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions |
| 4583 | ** return the P argument from the previous call of the same function |
| 4584 | ** on the same [database connection] D, or NULL for |
| 4585 | ** the first call for each function on D. |
| 4586 | ** |
| 4587 | ** The commit and rollback hook callbacks are not reentrant. |
| 4588 | ** The callback implementation must not do anything that will modify |
| 4589 | ** the database connection that invoked the callback. Any actions |
| 4590 | ** to modify the database connection must be deferred until after the |
| 4591 | ** completion of the [sqlite3_step()] call that triggered the commit |
| 4592 | ** or rollback hook in the first place. |
| 4593 | ** Note that running any other SQL statements, including SELECT statements, |
| 4594 | ** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify |
| 4595 | ** the database connections for the meaning of "modify" in this paragraph. |
| 4596 | ** |
| 4597 | ** ^Registering a NULL function disables the callback. |
| 4598 | ** |
| 4599 | ** ^When the commit hook callback routine returns zero, the [COMMIT] |
| 4600 | ** operation is allowed to continue normally. ^If the commit hook |
| 4601 | ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK]. |
| 4602 | ** ^The rollback hook is invoked on a rollback that results from a commit |
| 4603 | ** hook returning non-zero, just as it would be with any other rollback. |
| 4604 | ** |
| 4605 | ** ^For the purposes of this API, a transaction is said to have been |
| 4606 | ** rolled back if an explicit "ROLLBACK" statement is executed, or |
| 4607 | ** an error or constraint causes an implicit rollback to occur. |
| 4608 | ** ^The rollback callback is not invoked if a transaction is |
| 4609 | ** automatically rolled back because the database connection is closed. |
| 4610 | ** |
| 4611 | ** See also the [sqlite3_update_hook()] interface. |
| 4612 | */ |
| 4613 | SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); |
| 4614 | SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); |
| 4615 | |
| 4616 | /* |
| 4617 | ** CAPI3REF: Data Change Notification Callbacks |
| 4618 | ** |
| 4619 | ** ^The sqlite3_update_hook() interface registers a callback function |
| 4620 | ** with the [database connection] identified by the first argument |
| 4621 | ** to be invoked whenever a row is updated, inserted or deleted. |
| 4622 | ** ^Any callback set by a previous call to this function |
| 4623 | ** for the same database connection is overridden. |
| 4624 | ** |
| 4625 | ** ^The second argument is a pointer to the function to invoke when a |
| 4626 | ** row is updated, inserted or deleted. |
| 4627 | ** ^The first argument to the callback is a copy of the third argument |
| 4628 | ** to sqlite3_update_hook(). |
| 4629 | ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE], |
| 4630 | ** or [SQLITE_UPDATE], depending on the operation that caused the callback |
| 4631 | ** to be invoked. |
| 4632 | ** ^The third and fourth arguments to the callback contain pointers to the |
| 4633 | ** database and table name containing the affected row. |
| 4634 | ** ^The final callback parameter is the [rowid] of the row. |
| 4635 | ** ^In the case of an update, this is the [rowid] after the update takes place. |
| 4636 | ** |
| 4637 | ** ^(The update hook is not invoked when internal system tables are |
| 4638 | ** modified (i.e. sqlite_master and sqlite_sequence).)^ |
| 4639 | ** |
| 4640 | ** ^In the current implementation, the update hook |
| 4641 | ** is not invoked when duplication rows are deleted because of an |
| 4642 | ** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook |
| 4643 | ** invoked when rows are deleted using the [truncate optimization]. |
| 4644 | ** The exceptions defined in this paragraph might change in a future |
| 4645 | ** release of SQLite. |
| 4646 | ** |
| 4647 | ** The update hook implementation must not do anything that will modify |
| 4648 | ** the database connection that invoked the update hook. Any actions |
| 4649 | ** to modify the database connection must be deferred until after the |
| 4650 | ** completion of the [sqlite3_step()] call that triggered the update hook. |
| 4651 | ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their |
| 4652 | ** database connections for the meaning of "modify" in this paragraph. |
| 4653 | ** |
| 4654 | ** ^The sqlite3_update_hook(D,C,P) function |
| 4655 | ** returns the P argument from the previous call |
| 4656 | ** on the same [database connection] D, or NULL for |
| 4657 | ** the first call on D. |
| 4658 | ** |
| 4659 | ** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()] |
| 4660 | ** interfaces. |
| 4661 | */ |
| 4662 | SQLITE_API void *sqlite3_update_hook( |
| 4663 | sqlite3*, |
| 4664 | void(*)(void *,int ,char const *,char const *,sqlite3_int64), |
| 4665 | void* |
| 4666 | ); |
| 4667 | |
| 4668 | /* |
| 4669 | ** CAPI3REF: Enable Or Disable Shared Pager Cache |
| 4670 | ** |
| 4671 | ** ^(This routine enables or disables the sharing of the database cache |
| 4672 | ** and schema data structures between [database connection | connections] |
| 4673 | ** to the same database. Sharing is enabled if the argument is true |
| 4674 | ** and disabled if the argument is false.)^ |
| 4675 | ** |
| 4676 | ** ^Cache sharing is enabled and disabled for an entire process. |
| 4677 | ** This is a change as of SQLite version 3.5.0. In prior versions of SQLite, |
| 4678 | ** sharing was enabled or disabled for each thread separately. |
| 4679 | ** |
| 4680 | ** ^(The cache sharing mode set by this interface effects all subsequent |
| 4681 | ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. |
| 4682 | ** Existing database connections continue use the sharing mode |
| 4683 | ** that was in effect at the time they were opened.)^ |
| 4684 | ** |
| 4685 | ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled |
| 4686 | ** successfully. An [error code] is returned otherwise.)^ |
| 4687 | ** |
| 4688 | ** ^Shared cache is disabled by default. But this might change in |
| 4689 | ** future releases of SQLite. Applications that care about shared |
| 4690 | ** cache setting should set it explicitly. |
| 4691 | ** |
| 4692 | ** See Also: [SQLite Shared-Cache Mode] |
| 4693 | */ |
| 4694 | SQLITE_API int sqlite3_enable_shared_cache(int); |
| 4695 | |
| 4696 | /* |
| 4697 | ** CAPI3REF: Attempt To Free Heap Memory |
| 4698 | ** |
| 4699 | ** ^The sqlite3_release_memory() interface attempts to free N bytes |
| 4700 | ** of heap memory by deallocating non-essential memory allocations |
| 4701 | ** held by the database library. Memory used to cache database |
| 4702 | ** pages to improve performance is an example of non-essential memory. |
| 4703 | ** ^sqlite3_release_memory() returns the number of bytes actually freed, |
| 4704 | ** which might be more or less than the amount requested. |
| 4705 | ** ^The sqlite3_release_memory() routine is a no-op returning zero |
| 4706 | ** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT]. |
| 4707 | ** |
| 4708 | ** See also: [sqlite3_db_release_memory()] |
| 4709 | */ |
| 4710 | SQLITE_API int sqlite3_release_memory(int); |
| 4711 | |
| 4712 | /* |
| 4713 | ** CAPI3REF: Free Memory Used By A Database Connection |
| 4714 | ** |
| 4715 | ** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap |
| 4716 | ** memory as possible from database connection D. Unlike the |
| 4717 | ** [sqlite3_release_memory()] interface, this interface is effect even |
| 4718 | ** when then [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is |
| 4719 | ** omitted. |
| 4720 | ** |
| 4721 | ** See also: [sqlite3_release_memory()] |
| 4722 | */ |
| 4723 | SQLITE_API int sqlite3_db_release_memory(sqlite3*); |
| 4724 | |
| 4725 | /* |
| 4726 | ** CAPI3REF: Impose A Limit On Heap Size |
| 4727 | ** |
| 4728 | ** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the |
| 4729 | ** soft limit on the amount of heap memory that may be allocated by SQLite. |
| 4730 | ** ^SQLite strives to keep heap memory utilization below the soft heap |
| 4731 | ** limit by reducing the number of pages held in the page cache |
| 4732 | ** as heap memory usages approaches the limit. |
| 4733 | ** ^The soft heap limit is "soft" because even though SQLite strives to stay |
| 4734 | ** below the limit, it will exceed the limit rather than generate |
| 4735 | ** an [SQLITE_NOMEM] error. In other words, the soft heap limit |
| 4736 | ** is advisory only. |
| 4737 | ** |
| 4738 | ** ^The return value from sqlite3_soft_heap_limit64() is the size of |
| 4739 | ** the soft heap limit prior to the call, or negative in the case of an |
| 4740 | ** error. ^If the argument N is negative |
| 4741 | ** then no change is made to the soft heap limit. Hence, the current |
| 4742 | ** size of the soft heap limit can be determined by invoking |
| 4743 | ** sqlite3_soft_heap_limit64() with a negative argument. |
| 4744 | ** |
| 4745 | ** ^If the argument N is zero then the soft heap limit is disabled. |
| 4746 | ** |
| 4747 | ** ^(The soft heap limit is not enforced in the current implementation |
| 4748 | ** if one or more of following conditions are true: |
| 4749 | ** |
| 4750 | ** <ul> |
| 4751 | ** <li> The soft heap limit is set to zero. |
| 4752 | ** <li> Memory accounting is disabled using a combination of the |
| 4753 | ** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and |
| 4754 | ** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option. |
| 4755 | ** <li> An alternative page cache implementation is specified using |
| 4756 | ** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...). |
| 4757 | ** <li> The page cache allocates from its own memory pool supplied |
| 4758 | ** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than |
| 4759 | ** from the heap. |
| 4760 | ** </ul>)^ |
| 4761 | ** |
| 4762 | ** Beginning with SQLite version 3.7.3, the soft heap limit is enforced |
| 4763 | ** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT] |
| 4764 | ** compile-time option is invoked. With [SQLITE_ENABLE_MEMORY_MANAGEMENT], |
| 4765 | ** the soft heap limit is enforced on every memory allocation. Without |
| 4766 | ** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced |
| 4767 | ** when memory is allocated by the page cache. Testing suggests that because |
| 4768 | ** the page cache is the predominate memory user in SQLite, most |
| 4769 | ** applications will achieve adequate soft heap limit enforcement without |
| 4770 | ** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT]. |
| 4771 | ** |
| 4772 | ** The circumstances under which SQLite will enforce the soft heap limit may |
| 4773 | ** changes in future releases of SQLite. |
| 4774 | */ |
| 4775 | SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N); |
| 4776 | |
| 4777 | /* |
| 4778 | ** CAPI3REF: Deprecated Soft Heap Limit Interface |
| 4779 | ** DEPRECATED |
| 4780 | ** |
| 4781 | ** This is a deprecated version of the [sqlite3_soft_heap_limit64()] |
| 4782 | ** interface. This routine is provided for historical compatibility |
| 4783 | ** only. All new applications should use the |
| 4784 | ** [sqlite3_soft_heap_limit64()] interface rather than this one. |
| 4785 | */ |
| 4786 | SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N); |
| 4787 | |
| 4788 | |
| 4789 | /* |
| 4790 | ** CAPI3REF: Extract Metadata About A Column Of A Table |
| 4791 | ** |
| 4792 | ** ^This routine returns metadata about a specific column of a specific |
| 4793 | ** database table accessible using the [database connection] handle |
| 4794 | ** passed as the first function argument. |
| 4795 | ** |
| 4796 | ** ^The column is identified by the second, third and fourth parameters to |
| 4797 | ** this function. ^The second parameter is either the name of the database |
| 4798 | ** (i.e. "main", "temp", or an attached database) containing the specified |
| 4799 | ** table or NULL. ^If it is NULL, then all attached databases are searched |
| 4800 | ** for the table using the same algorithm used by the database engine to |
| 4801 | ** resolve unqualified table references. |
| 4802 | ** |
| 4803 | ** ^The third and fourth parameters to this function are the table and column |
| 4804 | ** name of the desired column, respectively. Neither of these parameters |
| 4805 | ** may be NULL. |
| 4806 | ** |
| 4807 | ** ^Metadata is returned by writing to the memory locations passed as the 5th |
| 4808 | ** and subsequent parameters to this function. ^Any of these arguments may be |
| 4809 | ** NULL, in which case the corresponding element of metadata is omitted. |
| 4810 | ** |
| 4811 | ** ^(<blockquote> |
| 4812 | ** <table border="1"> |
| 4813 | ** <tr><th> Parameter <th> Output<br>Type <th> Description |
| 4814 | ** |
| 4815 | ** <tr><td> 5th <td> const char* <td> Data type |
| 4816 | ** <tr><td> 6th <td> const char* <td> Name of default collation sequence |
| 4817 | ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint |
| 4818 | ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY |
| 4819 | ** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT] |
| 4820 | ** </table> |
| 4821 | ** </blockquote>)^ |
| 4822 | ** |
| 4823 | ** ^The memory pointed to by the character pointers returned for the |
| 4824 | ** declaration type and collation sequence is valid only until the next |
| 4825 | ** call to any SQLite API function. |
| 4826 | ** |
| 4827 | ** ^If the specified table is actually a view, an [error code] is returned. |
| 4828 | ** |
| 4829 | ** ^If the specified column is "rowid", "oid" or "_rowid_" and an |
| 4830 | ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output |
| 4831 | ** parameters are set for the explicitly declared column. ^(If there is no |
| 4832 | ** explicitly declared [INTEGER PRIMARY KEY] column, then the output |
| 4833 | ** parameters are set as follows: |
| 4834 | ** |
| 4835 | ** <pre> |
| 4836 | ** data type: "INTEGER" |
| 4837 | ** collation sequence: "BINARY" |
| 4838 | ** not null: 0 |
| 4839 | ** primary key: 1 |
| 4840 | ** auto increment: 0 |
| 4841 | ** </pre>)^ |
| 4842 | ** |
| 4843 | ** ^(This function may load one or more schemas from database files. If an |
| 4844 | ** error occurs during this process, or if the requested table or column |
| 4845 | ** cannot be found, an [error code] is returned and an error message left |
| 4846 | ** in the [database connection] (to be retrieved using sqlite3_errmsg()).)^ |
| 4847 | ** |
| 4848 | ** ^This API is only available if the library was compiled with the |
| 4849 | ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined. |
| 4850 | */ |
| 4851 | SQLITE_API int sqlite3_table_column_metadata( |
| 4852 | sqlite3 *db, /* Connection handle */ |
| 4853 | const char *zDbName, /* Database name or NULL */ |
| 4854 | const char *zTableName, /* Table name */ |
| 4855 | const char *zColumnName, /* Column name */ |
| 4856 | char const **pzDataType, /* OUTPUT: Declared data type */ |
| 4857 | char const **pzCollSeq, /* OUTPUT: Collation sequence name */ |
| 4858 | int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ |
| 4859 | int *pPrimaryKey, /* OUTPUT: True if column part of PK */ |
| 4860 | int *pAutoinc /* OUTPUT: True if column is auto-increment */ |
| 4861 | ); |
| 4862 | |
| 4863 | /* |
| 4864 | ** CAPI3REF: Load An Extension |
| 4865 | ** |
| 4866 | ** ^This interface loads an SQLite extension library from the named file. |
| 4867 | ** |
| 4868 | ** ^The sqlite3_load_extension() interface attempts to load an |
| 4869 | ** SQLite extension library contained in the file zFile. |
| 4870 | ** |
| 4871 | ** ^The entry point is zProc. |
| 4872 | ** ^zProc may be 0, in which case the name of the entry point |
| 4873 | ** defaults to "sqlite3_extension_init". |
| 4874 | ** ^The sqlite3_load_extension() interface returns |
| 4875 | ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. |
| 4876 | ** ^If an error occurs and pzErrMsg is not 0, then the |
| 4877 | ** [sqlite3_load_extension()] interface shall attempt to |
| 4878 | ** fill *pzErrMsg with error message text stored in memory |
| 4879 | ** obtained from [sqlite3_malloc()]. The calling function |
| 4880 | ** should free this memory by calling [sqlite3_free()]. |
| 4881 | ** |
| 4882 | ** ^Extension loading must be enabled using |
| 4883 | ** [sqlite3_enable_load_extension()] prior to calling this API, |
| 4884 | ** otherwise an error will be returned. |
| 4885 | ** |
| 4886 | ** See also the [load_extension() SQL function]. |
| 4887 | */ |
| 4888 | SQLITE_API int sqlite3_load_extension( |
| 4889 | sqlite3 *db, /* Load the extension into this database connection */ |
| 4890 | const char *zFile, /* Name of the shared library containing extension */ |
| 4891 | const char *zProc, /* Entry point. Derived from zFile if 0 */ |
| 4892 | char **pzErrMsg /* Put error message here if not 0 */ |
| 4893 | ); |
| 4894 | |
| 4895 | /* |
| 4896 | ** CAPI3REF: Enable Or Disable Extension Loading |
| 4897 | ** |
| 4898 | ** ^So as not to open security holes in older applications that are |
| 4899 | ** unprepared to deal with extension loading, and as a means of disabling |
| 4900 | ** extension loading while evaluating user-entered SQL, the following API |
| 4901 | ** is provided to turn the [sqlite3_load_extension()] mechanism on and off. |
| 4902 | ** |
| 4903 | ** ^Extension loading is off by default. See ticket #1863. |
| 4904 | ** ^Call the sqlite3_enable_load_extension() routine with onoff==1 |
| 4905 | ** to turn extension loading on and call it with onoff==0 to turn |
| 4906 | ** it back off again. |
| 4907 | */ |
| 4908 | SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff); |
| 4909 | |
| 4910 | /* |
| 4911 | ** CAPI3REF: Automatically Load Statically Linked Extensions |
| 4912 | ** |
| 4913 | ** ^This interface causes the xEntryPoint() function to be invoked for |
| 4914 | ** each new [database connection] that is created. The idea here is that |
| 4915 | ** xEntryPoint() is the entry point for a statically linked SQLite extension |
| 4916 | ** that is to be automatically loaded into all new database connections. |
| 4917 | ** |
| 4918 | ** ^(Even though the function prototype shows that xEntryPoint() takes |
| 4919 | ** no arguments and returns void, SQLite invokes xEntryPoint() with three |
| 4920 | ** arguments and expects and integer result as if the signature of the |
| 4921 | ** entry point where as follows: |
| 4922 | ** |
| 4923 | ** <blockquote><pre> |
| 4924 | ** int xEntryPoint( |
| 4925 | ** sqlite3 *db, |
| 4926 | ** const char **pzErrMsg, |
| 4927 | ** const struct sqlite3_api_routines *pThunk |
| 4928 | ** ); |
| 4929 | ** </pre></blockquote>)^ |
| 4930 | ** |
| 4931 | ** If the xEntryPoint routine encounters an error, it should make *pzErrMsg |
| 4932 | ** point to an appropriate error message (obtained from [sqlite3_mprintf()]) |
| 4933 | ** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg |
| 4934 | ** is NULL before calling the xEntryPoint(). ^SQLite will invoke |
| 4935 | ** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any |
| 4936 | ** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()], |
| 4937 | ** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail. |
| 4938 | ** |
| 4939 | ** ^Calling sqlite3_auto_extension(X) with an entry point X that is already |
| 4940 | ** on the list of automatic extensions is a harmless no-op. ^No entry point |
| 4941 | ** will be called more than once for each database connection that is opened. |
| 4942 | ** |
| 4943 | ** See also: [sqlite3_reset_auto_extension()]. |
| 4944 | */ |
| 4945 | SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void)); |
| 4946 | |
| 4947 | /* |
| 4948 | ** CAPI3REF: Reset Automatic Extension Loading |
| 4949 | ** |
| 4950 | ** ^This interface disables all automatic extensions previously |
| 4951 | ** registered using [sqlite3_auto_extension()]. |
| 4952 | */ |
| 4953 | SQLITE_API void sqlite3_reset_auto_extension(void); |
| 4954 | |
| 4955 | /* |
| 4956 | ** The interface to the virtual-table mechanism is currently considered |
| 4957 | ** to be experimental. The interface might change in incompatible ways. |
| 4958 | ** If this is a problem for you, do not use the interface at this time. |
| 4959 | ** |
| 4960 | ** When the virtual-table mechanism stabilizes, we will declare the |
| 4961 | ** interface fixed, support it indefinitely, and remove this comment. |
| 4962 | */ |
| 4963 | |
| 4964 | /* |
| 4965 | ** Structures used by the virtual table interface |
| 4966 | */ |
| 4967 | typedef struct sqlite3_vtab sqlite3_vtab; |
| 4968 | typedef struct sqlite3_index_info sqlite3_index_info; |
| 4969 | typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; |
| 4970 | typedef struct sqlite3_module sqlite3_module; |
| 4971 | |
| 4972 | /* |
| 4973 | ** CAPI3REF: Virtual Table Object |
| 4974 | ** KEYWORDS: sqlite3_module {virtual table module} |
| 4975 | ** |
| 4976 | ** This structure, sometimes called a "virtual table module", |
| 4977 | ** defines the implementation of a [virtual tables]. |
| 4978 | ** This structure consists mostly of methods for the module. |
| 4979 | ** |
| 4980 | ** ^A virtual table module is created by filling in a persistent |
| 4981 | ** instance of this structure and passing a pointer to that instance |
| 4982 | ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()]. |
| 4983 | ** ^The registration remains valid until it is replaced by a different |
| 4984 | ** module or until the [database connection] closes. The content |
| 4985 | ** of this structure must not change while it is registered with |
| 4986 | ** any database connection. |
| 4987 | */ |
| 4988 | struct sqlite3_module { |
| 4989 | int iVersion; |
| 4990 | int (*xCreate)(sqlite3*, void *pAux, |
| 4991 | int argc, const char *const*argv, |
| 4992 | sqlite3_vtab **ppVTab, char**); |
| 4993 | int (*xConnect)(sqlite3*, void *pAux, |
| 4994 | int argc, const char *const*argv, |
| 4995 | sqlite3_vtab **ppVTab, char**); |
| 4996 | int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); |
| 4997 | int (*xDisconnect)(sqlite3_vtab *pVTab); |
| 4998 | int (*xDestroy)(sqlite3_vtab *pVTab); |
| 4999 | int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); |
| 5000 | int (*xClose)(sqlite3_vtab_cursor*); |
| 5001 | int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, |
| 5002 | int argc, sqlite3_value **argv); |
| 5003 | int (*xNext)(sqlite3_vtab_cursor*); |
| 5004 | int (*xEof)(sqlite3_vtab_cursor*); |
| 5005 | int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); |
| 5006 | int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); |
| 5007 | int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); |
| 5008 | int (*xBegin)(sqlite3_vtab *pVTab); |
| 5009 | int (*xSync)(sqlite3_vtab *pVTab); |
| 5010 | int (*xCommit)(sqlite3_vtab *pVTab); |
| 5011 | int (*xRollback)(sqlite3_vtab *pVTab); |
| 5012 | int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, |
| 5013 | void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), |
| 5014 | void **ppArg); |
| 5015 | int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); |
| 5016 | /* The methods above are in version 1 of the sqlite_module object. Those |
| 5017 | ** below are for version 2 and greater. */ |
| 5018 | int (*xSavepoint)(sqlite3_vtab *pVTab, int); |
| 5019 | int (*xRelease)(sqlite3_vtab *pVTab, int); |
| 5020 | int (*xRollbackTo)(sqlite3_vtab *pVTab, int); |
| 5021 | }; |
| 5022 | |
| 5023 | /* |
| 5024 | ** CAPI3REF: Virtual Table Indexing Information |
| 5025 | ** KEYWORDS: sqlite3_index_info |
| 5026 | ** |
| 5027 | ** The sqlite3_index_info structure and its substructures is used as part |
| 5028 | ** of the [virtual table] interface to |
| 5029 | ** pass information into and receive the reply from the [xBestIndex] |
| 5030 | ** method of a [virtual table module]. The fields under **Inputs** are the |
| 5031 | ** inputs to xBestIndex and are read-only. xBestIndex inserts its |
| 5032 | ** results into the **Outputs** fields. |
| 5033 | ** |
| 5034 | ** ^(The aConstraint[] array records WHERE clause constraints of the form: |
| 5035 | ** |
| 5036 | ** <blockquote>column OP expr</blockquote> |
| 5037 | ** |
| 5038 | ** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is |
| 5039 | ** stored in aConstraint[].op using one of the |
| 5040 | ** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^ |
| 5041 | ** ^(The index of the column is stored in |
| 5042 | ** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the |
| 5043 | ** expr on the right-hand side can be evaluated (and thus the constraint |
| 5044 | ** is usable) and false if it cannot.)^ |
| 5045 | ** |
| 5046 | ** ^The optimizer automatically inverts terms of the form "expr OP column" |
| 5047 | ** and makes other simplifications to the WHERE clause in an attempt to |
| 5048 | ** get as many WHERE clause terms into the form shown above as possible. |
| 5049 | ** ^The aConstraint[] array only reports WHERE clause terms that are |
| 5050 | ** relevant to the particular virtual table being queried. |
| 5051 | ** |
| 5052 | ** ^Information about the ORDER BY clause is stored in aOrderBy[]. |
| 5053 | ** ^Each term of aOrderBy records a column of the ORDER BY clause. |
| 5054 | ** |
| 5055 | ** The [xBestIndex] method must fill aConstraintUsage[] with information |
| 5056 | ** about what parameters to pass to xFilter. ^If argvIndex>0 then |
| 5057 | ** the right-hand side of the corresponding aConstraint[] is evaluated |
| 5058 | ** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit |
| 5059 | ** is true, then the constraint is assumed to be fully handled by the |
| 5060 | ** virtual table and is not checked again by SQLite.)^ |
| 5061 | ** |
| 5062 | ** ^The idxNum and idxPtr values are recorded and passed into the |
| 5063 | ** [xFilter] method. |
| 5064 | ** ^[sqlite3_free()] is used to free idxPtr if and only if |
| 5065 | ** needToFreeIdxPtr is true. |
| 5066 | ** |
| 5067 | ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in |
| 5068 | ** the correct order to satisfy the ORDER BY clause so that no separate |
| 5069 | ** sorting step is required. |
| 5070 | ** |
| 5071 | ** ^The estimatedCost value is an estimate of the cost of doing the |
| 5072 | ** particular lookup. A full scan of a table with N entries should have |
| 5073 | ** a cost of N. A binary search of a table of N entries should have a |
| 5074 | ** cost of approximately log(N). |
| 5075 | */ |
| 5076 | struct sqlite3_index_info { |
| 5077 | /* Inputs */ |
| 5078 | int nConstraint; /* Number of entries in aConstraint */ |
| 5079 | struct sqlite3_index_constraint { |
| 5080 | int iColumn; /* Column on left-hand side of constraint */ |
| 5081 | unsigned char op; /* Constraint operator */ |
| 5082 | unsigned char usable; /* True if this constraint is usable */ |
| 5083 | int iTermOffset; /* Used internally - xBestIndex should ignore */ |
| 5084 | } *aConstraint; /* Table of WHERE clause constraints */ |
| 5085 | int nOrderBy; /* Number of terms in the ORDER BY clause */ |
| 5086 | struct sqlite3_index_orderby { |
| 5087 | int iColumn; /* Column number */ |
| 5088 | unsigned char desc; /* True for DESC. False for ASC. */ |
| 5089 | } *aOrderBy; /* The ORDER BY clause */ |
| 5090 | /* Outputs */ |
| 5091 | struct sqlite3_index_constraint_usage { |
| 5092 | int argvIndex; /* if >0, constraint is part of argv to xFilter */ |
| 5093 | unsigned char omit; /* Do not code a test for this constraint */ |
| 5094 | } *aConstraintUsage; |
| 5095 | int idxNum; /* Number used to identify the index */ |
| 5096 | char *idxStr; /* String, possibly obtained from sqlite3_malloc */ |
| 5097 | int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ |
| 5098 | int orderByConsumed; /* True if output is already ordered */ |
| 5099 | double estimatedCost; /* Estimated cost of using this index */ |
| 5100 | }; |
| 5101 | |
| 5102 | /* |
| 5103 | ** CAPI3REF: Virtual Table Constraint Operator Codes |
| 5104 | ** |
| 5105 | ** These macros defined the allowed values for the |
| 5106 | ** [sqlite3_index_info].aConstraint[].op field. Each value represents |
| 5107 | ** an operator that is part of a constraint term in the wHERE clause of |
| 5108 | ** a query that uses a [virtual table]. |
| 5109 | */ |
| 5110 | #define SQLITE_INDEX_CONSTRAINT_EQ 2 |
| 5111 | #define SQLITE_INDEX_CONSTRAINT_GT 4 |
| 5112 | #define SQLITE_INDEX_CONSTRAINT_LE 8 |
| 5113 | #define SQLITE_INDEX_CONSTRAINT_LT 16 |
| 5114 | #define SQLITE_INDEX_CONSTRAINT_GE 32 |
| 5115 | #define SQLITE_INDEX_CONSTRAINT_MATCH 64 |
| 5116 | |
| 5117 | /* |
| 5118 | ** CAPI3REF: Register A Virtual Table Implementation |
| 5119 | ** |
| 5120 | ** ^These routines are used to register a new [virtual table module] name. |
| 5121 | ** ^Module names must be registered before |
| 5122 | ** creating a new [virtual table] using the module and before using a |
| 5123 | ** preexisting [virtual table] for the module. |
| 5124 | ** |
| 5125 | ** ^The module name is registered on the [database connection] specified |
| 5126 | ** by the first parameter. ^The name of the module is given by the |
| 5127 | ** second parameter. ^The third parameter is a pointer to |
| 5128 | ** the implementation of the [virtual table module]. ^The fourth |
| 5129 | ** parameter is an arbitrary client data pointer that is passed through |
| 5130 | ** into the [xCreate] and [xConnect] methods of the virtual table module |
| 5131 | ** when a new virtual table is be being created or reinitialized. |
| 5132 | ** |
| 5133 | ** ^The sqlite3_create_module_v2() interface has a fifth parameter which |
| 5134 | ** is a pointer to a destructor for the pClientData. ^SQLite will |
| 5135 | ** invoke the destructor function (if it is not NULL) when SQLite |
| 5136 | ** no longer needs the pClientData pointer. ^The destructor will also |
| 5137 | ** be invoked if the call to sqlite3_create_module_v2() fails. |
| 5138 | ** ^The sqlite3_create_module() |
| 5139 | ** interface is equivalent to sqlite3_create_module_v2() with a NULL |
| 5140 | ** destructor. |
| 5141 | */ |
| 5142 | SQLITE_API int sqlite3_create_module( |
| 5143 | sqlite3 *db, /* SQLite connection to register module with */ |
| 5144 | const char *zName, /* Name of the module */ |
| 5145 | const sqlite3_module *p, /* Methods for the module */ |
| 5146 | void *pClientData /* Client data for xCreate/xConnect */ |
| 5147 | ); |
| 5148 | SQLITE_API int sqlite3_create_module_v2( |
| 5149 | sqlite3 *db, /* SQLite connection to register module with */ |
| 5150 | const char *zName, /* Name of the module */ |
| 5151 | const sqlite3_module *p, /* Methods for the module */ |
| 5152 | void *pClientData, /* Client data for xCreate/xConnect */ |
| 5153 | void(*xDestroy)(void*) /* Module destructor function */ |
| 5154 | ); |
| 5155 | |
| 5156 | /* |
| 5157 | ** CAPI3REF: Virtual Table Instance Object |
| 5158 | ** KEYWORDS: sqlite3_vtab |
| 5159 | ** |
| 5160 | ** Every [virtual table module] implementation uses a subclass |
| 5161 | ** of this object to describe a particular instance |
| 5162 | ** of the [virtual table]. Each subclass will |
| 5163 | ** be tailored to the specific needs of the module implementation. |
| 5164 | ** The purpose of this superclass is to define certain fields that are |
| 5165 | ** common to all module implementations. |
| 5166 | ** |
| 5167 | ** ^Virtual tables methods can set an error message by assigning a |
| 5168 | ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should |
| 5169 | ** take care that any prior string is freed by a call to [sqlite3_free()] |
| 5170 | ** prior to assigning a new string to zErrMsg. ^After the error message |
| 5171 | ** is delivered up to the client application, the string will be automatically |
| 5172 | ** freed by sqlite3_free() and the zErrMsg field will be zeroed. |
| 5173 | */ |
| 5174 | struct sqlite3_vtab { |
| 5175 | const sqlite3_module *pModule; /* The module for this virtual table */ |
| 5176 | int nRef; /* NO LONGER USED */ |
| 5177 | char *zErrMsg; /* Error message from sqlite3_mprintf() */ |
| 5178 | /* Virtual table implementations will typically add additional fields */ |
| 5179 | }; |
| 5180 | |
| 5181 | /* |
| 5182 | ** CAPI3REF: Virtual Table Cursor Object |
| 5183 | ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor} |
| 5184 | ** |
| 5185 | ** Every [virtual table module] implementation uses a subclass of the |
| 5186 | ** following structure to describe cursors that point into the |
| 5187 | ** [virtual table] and are used |
| 5188 | ** to loop through the virtual table. Cursors are created using the |
| 5189 | ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed |
| 5190 | ** by the [sqlite3_module.xClose | xClose] method. Cursors are used |
| 5191 | ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods |
| 5192 | ** of the module. Each module implementation will define |
| 5193 | ** the content of a cursor structure to suit its own needs. |
| 5194 | ** |
| 5195 | ** This superclass exists in order to define fields of the cursor that |
| 5196 | ** are common to all implementations. |
| 5197 | */ |
| 5198 | struct sqlite3_vtab_cursor { |
| 5199 | sqlite3_vtab *pVtab; /* Virtual table of this cursor */ |
| 5200 | /* Virtual table implementations will typically add additional fields */ |
| 5201 | }; |
| 5202 | |
| 5203 | /* |
| 5204 | ** CAPI3REF: Declare The Schema Of A Virtual Table |
| 5205 | ** |
| 5206 | ** ^The [xCreate] and [xConnect] methods of a |
| 5207 | ** [virtual table module] call this interface |
| 5208 | ** to declare the format (the names and datatypes of the columns) of |
| 5209 | ** the virtual tables they implement. |
| 5210 | */ |
| 5211 | SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL); |
| 5212 | |
| 5213 | /* |
| 5214 | ** CAPI3REF: Overload A Function For A Virtual Table |
| 5215 | ** |
| 5216 | ** ^(Virtual tables can provide alternative implementations of functions |
| 5217 | ** using the [xFindFunction] method of the [virtual table module]. |
| 5218 | ** But global versions of those functions |
| 5219 | ** must exist in order to be overloaded.)^ |
| 5220 | ** |
| 5221 | ** ^(This API makes sure a global version of a function with a particular |
| 5222 | ** name and number of parameters exists. If no such function exists |
| 5223 | ** before this API is called, a new function is created.)^ ^The implementation |
| 5224 | ** of the new function always causes an exception to be thrown. So |
| 5225 | ** the new function is not good for anything by itself. Its only |
| 5226 | ** purpose is to be a placeholder function that can be overloaded |
| 5227 | ** by a [virtual table]. |
| 5228 | */ |
| 5229 | SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg); |
| 5230 | |
| 5231 | /* |
| 5232 | ** The interface to the virtual-table mechanism defined above (back up |
| 5233 | ** to a comment remarkably similar to this one) is currently considered |
| 5234 | ** to be experimental. The interface might change in incompatible ways. |
| 5235 | ** If this is a problem for you, do not use the interface at this time. |
| 5236 | ** |
| 5237 | ** When the virtual-table mechanism stabilizes, we will declare the |
| 5238 | ** interface fixed, support it indefinitely, and remove this comment. |
| 5239 | */ |
| 5240 | |
| 5241 | /* |
| 5242 | ** CAPI3REF: A Handle To An Open BLOB |
| 5243 | ** KEYWORDS: {BLOB handle} {BLOB handles} |
| 5244 | ** |
| 5245 | ** An instance of this object represents an open BLOB on which |
| 5246 | ** [sqlite3_blob_open | incremental BLOB I/O] can be performed. |
| 5247 | ** ^Objects of this type are created by [sqlite3_blob_open()] |
| 5248 | ** and destroyed by [sqlite3_blob_close()]. |
| 5249 | ** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces |
| 5250 | ** can be used to read or write small subsections of the BLOB. |
| 5251 | ** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes. |
| 5252 | */ |
| 5253 | typedef struct sqlite3_blob sqlite3_blob; |
| 5254 | |
| 5255 | /* |
| 5256 | ** CAPI3REF: Open A BLOB For Incremental I/O |
| 5257 | ** |
| 5258 | ** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located |
| 5259 | ** in row iRow, column zColumn, table zTable in database zDb; |
| 5260 | ** in other words, the same BLOB that would be selected by: |
| 5261 | ** |
| 5262 | ** <pre> |
| 5263 | ** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow; |
| 5264 | ** </pre>)^ |
| 5265 | ** |
| 5266 | ** ^If the flags parameter is non-zero, then the BLOB is opened for read |
| 5267 | ** and write access. ^If it is zero, the BLOB is opened for read access. |
| 5268 | ** ^It is not possible to open a column that is part of an index or primary |
| 5269 | ** key for writing. ^If [foreign key constraints] are enabled, it is |
| 5270 | ** not possible to open a column that is part of a [child key] for writing. |
| 5271 | ** |
| 5272 | ** ^Note that the database name is not the filename that contains |
| 5273 | ** the database but rather the symbolic name of the database that |
| 5274 | ** appears after the AS keyword when the database is connected using [ATTACH]. |
| 5275 | ** ^For the main database file, the database name is "main". |
| 5276 | ** ^For TEMP tables, the database name is "temp". |
| 5277 | ** |
| 5278 | ** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is written |
| 5279 | ** to *ppBlob. Otherwise an [error code] is returned and *ppBlob is set |
| 5280 | ** to be a null pointer.)^ |
| 5281 | ** ^This function sets the [database connection] error code and message |
| 5282 | ** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()] and related |
| 5283 | ** functions. ^Note that the *ppBlob variable is always initialized in a |
| 5284 | ** way that makes it safe to invoke [sqlite3_blob_close()] on *ppBlob |
| 5285 | ** regardless of the success or failure of this routine. |
| 5286 | ** |
| 5287 | ** ^(If the row that a BLOB handle points to is modified by an |
| 5288 | ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects |
| 5289 | ** then the BLOB handle is marked as "expired". |
| 5290 | ** This is true if any column of the row is changed, even a column |
| 5291 | ** other than the one the BLOB handle is open on.)^ |
| 5292 | ** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for |
| 5293 | ** an expired BLOB handle fail with a return code of [SQLITE_ABORT]. |
| 5294 | ** ^(Changes written into a BLOB prior to the BLOB expiring are not |
| 5295 | ** rolled back by the expiration of the BLOB. Such changes will eventually |
| 5296 | ** commit if the transaction continues to completion.)^ |
| 5297 | ** |
| 5298 | ** ^Use the [sqlite3_blob_bytes()] interface to determine the size of |
| 5299 | ** the opened blob. ^The size of a blob may not be changed by this |
| 5300 | ** interface. Use the [UPDATE] SQL command to change the size of a |
| 5301 | ** blob. |
| 5302 | ** |
| 5303 | ** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces |
| 5304 | ** and the built-in [zeroblob] SQL function can be used, if desired, |
| 5305 | ** to create an empty, zero-filled blob in which to read or write using |
| 5306 | ** this interface. |
| 5307 | ** |
| 5308 | ** To avoid a resource leak, every open [BLOB handle] should eventually |
| 5309 | ** be released by a call to [sqlite3_blob_close()]. |
| 5310 | */ |
| 5311 | SQLITE_API int sqlite3_blob_open( |
| 5312 | sqlite3*, |
| 5313 | const char *zDb, |
| 5314 | const char *zTable, |
| 5315 | const char *zColumn, |
| 5316 | sqlite3_int64 iRow, |
| 5317 | int flags, |
| 5318 | sqlite3_blob **ppBlob |
| 5319 | ); |
| 5320 | |
| 5321 | /* |
| 5322 | ** CAPI3REF: Move a BLOB Handle to a New Row |
| 5323 | ** |
| 5324 | ** ^This function is used to move an existing blob handle so that it points |
| 5325 | ** to a different row of the same database table. ^The new row is identified |
| 5326 | ** by the rowid value passed as the second argument. Only the row can be |
| 5327 | ** changed. ^The database, table and column on which the blob handle is open |
| 5328 | ** remain the same. Moving an existing blob handle to a new row can be |
| 5329 | ** faster than closing the existing handle and opening a new one. |
| 5330 | ** |
| 5331 | ** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] - |
| 5332 | ** it must exist and there must be either a blob or text value stored in |
| 5333 | ** the nominated column.)^ ^If the new row is not present in the table, or if |
| 5334 | ** it does not contain a blob or text value, or if another error occurs, an |
| 5335 | ** SQLite error code is returned and the blob handle is considered aborted. |
| 5336 | ** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or |
| 5337 | ** [sqlite3_blob_reopen()] on an aborted blob handle immediately return |
| 5338 | ** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle |
| 5339 | ** always returns zero. |
| 5340 | ** |
| 5341 | ** ^This function sets the database handle error code and message. |
| 5342 | */ |
| 5343 | SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64); |
| 5344 | |
| 5345 | /* |
| 5346 | ** CAPI3REF: Close A BLOB Handle |
| 5347 | ** |
| 5348 | ** ^Closes an open [BLOB handle]. |
| 5349 | ** |
| 5350 | ** ^Closing a BLOB shall cause the current transaction to commit |
| 5351 | ** if there are no other BLOBs, no pending prepared statements, and the |
| 5352 | ** database connection is in [autocommit mode]. |
| 5353 | ** ^If any writes were made to the BLOB, they might be held in cache |
| 5354 | ** until the close operation if they will fit. |
| 5355 | ** |
| 5356 | ** ^(Closing the BLOB often forces the changes |
| 5357 | ** out to disk and so if any I/O errors occur, they will likely occur |
| 5358 | ** at the time when the BLOB is closed. Any errors that occur during |
| 5359 | ** closing are reported as a non-zero return value.)^ |
| 5360 | ** |
| 5361 | ** ^(The BLOB is closed unconditionally. Even if this routine returns |
| 5362 | ** an error code, the BLOB is still closed.)^ |
| 5363 | ** |
| 5364 | ** ^Calling this routine with a null pointer (such as would be returned |
| 5365 | ** by a failed call to [sqlite3_blob_open()]) is a harmless no-op. |
| 5366 | */ |
| 5367 | SQLITE_API int sqlite3_blob_close(sqlite3_blob *); |
| 5368 | |
| 5369 | /* |
| 5370 | ** CAPI3REF: Return The Size Of An Open BLOB |
| 5371 | ** |
| 5372 | ** ^Returns the size in bytes of the BLOB accessible via the |
| 5373 | ** successfully opened [BLOB handle] in its only argument. ^The |
| 5374 | ** incremental blob I/O routines can only read or overwriting existing |
| 5375 | ** blob content; they cannot change the size of a blob. |
| 5376 | ** |
| 5377 | ** This routine only works on a [BLOB handle] which has been created |
| 5378 | ** by a prior successful call to [sqlite3_blob_open()] and which has not |
| 5379 | ** been closed by [sqlite3_blob_close()]. Passing any other pointer in |
| 5380 | ** to this routine results in undefined and probably undesirable behavior. |
| 5381 | */ |
| 5382 | SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *); |
| 5383 | |
| 5384 | /* |
| 5385 | ** CAPI3REF: Read Data From A BLOB Incrementally |
| 5386 | ** |
| 5387 | ** ^(This function is used to read data from an open [BLOB handle] into a |
| 5388 | ** caller-supplied buffer. N bytes of data are copied into buffer Z |
| 5389 | ** from the open BLOB, starting at offset iOffset.)^ |
| 5390 | ** |
| 5391 | ** ^If offset iOffset is less than N bytes from the end of the BLOB, |
| 5392 | ** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is |
| 5393 | ** less than zero, [SQLITE_ERROR] is returned and no data is read. |
| 5394 | ** ^The size of the blob (and hence the maximum value of N+iOffset) |
| 5395 | ** can be determined using the [sqlite3_blob_bytes()] interface. |
| 5396 | ** |
| 5397 | ** ^An attempt to read from an expired [BLOB handle] fails with an |
| 5398 | ** error code of [SQLITE_ABORT]. |
| 5399 | ** |
| 5400 | ** ^(On success, sqlite3_blob_read() returns SQLITE_OK. |
| 5401 | ** Otherwise, an [error code] or an [extended error code] is returned.)^ |
| 5402 | ** |
| 5403 | ** This routine only works on a [BLOB handle] which has been created |
| 5404 | ** by a prior successful call to [sqlite3_blob_open()] and which has not |
| 5405 | ** been closed by [sqlite3_blob_close()]. Passing any other pointer in |
| 5406 | ** to this routine results in undefined and probably undesirable behavior. |
| 5407 | ** |
| 5408 | ** See also: [sqlite3_blob_write()]. |
| 5409 | */ |
| 5410 | SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); |
| 5411 | |
| 5412 | /* |
| 5413 | ** CAPI3REF: Write Data Into A BLOB Incrementally |
| 5414 | ** |
| 5415 | ** ^This function is used to write data into an open [BLOB handle] from a |
| 5416 | ** caller-supplied buffer. ^N bytes of data are copied from the buffer Z |
| 5417 | ** into the open BLOB, starting at offset iOffset. |
| 5418 | ** |
| 5419 | ** ^If the [BLOB handle] passed as the first argument was not opened for |
| 5420 | ** writing (the flags parameter to [sqlite3_blob_open()] was zero), |
| 5421 | ** this function returns [SQLITE_READONLY]. |
| 5422 | ** |
| 5423 | ** ^This function may only modify the contents of the BLOB; it is |
| 5424 | ** not possible to increase the size of a BLOB using this API. |
| 5425 | ** ^If offset iOffset is less than N bytes from the end of the BLOB, |
| 5426 | ** [SQLITE_ERROR] is returned and no data is written. ^If N is |
| 5427 | ** less than zero [SQLITE_ERROR] is returned and no data is written. |
| 5428 | ** The size of the BLOB (and hence the maximum value of N+iOffset) |
| 5429 | ** can be determined using the [sqlite3_blob_bytes()] interface. |
| 5430 | ** |
| 5431 | ** ^An attempt to write to an expired [BLOB handle] fails with an |
| 5432 | ** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred |
| 5433 | ** before the [BLOB handle] expired are not rolled back by the |
| 5434 | ** expiration of the handle, though of course those changes might |
| 5435 | ** have been overwritten by the statement that expired the BLOB handle |
| 5436 | ** or by other independent statements. |
| 5437 | ** |
| 5438 | ** ^(On success, sqlite3_blob_write() returns SQLITE_OK. |
| 5439 | ** Otherwise, an [error code] or an [extended error code] is returned.)^ |
| 5440 | ** |
| 5441 | ** This routine only works on a [BLOB handle] which has been created |
| 5442 | ** by a prior successful call to [sqlite3_blob_open()] and which has not |
| 5443 | ** been closed by [sqlite3_blob_close()]. Passing any other pointer in |
| 5444 | ** to this routine results in undefined and probably undesirable behavior. |
| 5445 | ** |
| 5446 | ** See also: [sqlite3_blob_read()]. |
| 5447 | */ |
| 5448 | SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); |
| 5449 | |
| 5450 | /* |
| 5451 | ** CAPI3REF: Virtual File System Objects |
| 5452 | ** |
| 5453 | ** A virtual filesystem (VFS) is an [sqlite3_vfs] object |
| 5454 | ** that SQLite uses to interact |
| 5455 | ** with the underlying operating system. Most SQLite builds come with a |
| 5456 | ** single default VFS that is appropriate for the host computer. |
| 5457 | ** New VFSes can be registered and existing VFSes can be unregistered. |
| 5458 | ** The following interfaces are provided. |
| 5459 | ** |
| 5460 | ** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name. |
| 5461 | ** ^Names are case sensitive. |
| 5462 | ** ^Names are zero-terminated UTF-8 strings. |
| 5463 | ** ^If there is no match, a NULL pointer is returned. |
| 5464 | ** ^If zVfsName is NULL then the default VFS is returned. |
| 5465 | ** |
| 5466 | ** ^New VFSes are registered with sqlite3_vfs_register(). |
| 5467 | ** ^Each new VFS becomes the default VFS if the makeDflt flag is set. |
| 5468 | ** ^The same VFS can be registered multiple times without injury. |
| 5469 | ** ^To make an existing VFS into the default VFS, register it again |
| 5470 | ** with the makeDflt flag set. If two different VFSes with the |
| 5471 | ** same name are registered, the behavior is undefined. If a |
| 5472 | ** VFS is registered with a name that is NULL or an empty string, |
| 5473 | ** then the behavior is undefined. |
| 5474 | ** |
| 5475 | ** ^Unregister a VFS with the sqlite3_vfs_unregister() interface. |
| 5476 | ** ^(If the default VFS is unregistered, another VFS is chosen as |
| 5477 | ** the default. The choice for the new VFS is arbitrary.)^ |
| 5478 | */ |
| 5479 | SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName); |
| 5480 | SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); |
| 5481 | SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*); |
| 5482 | |
| 5483 | /* |
| 5484 | ** CAPI3REF: Mutexes |
| 5485 | ** |
| 5486 | ** The SQLite core uses these routines for thread |
| 5487 | ** synchronization. Though they are intended for internal |
| 5488 | ** use by SQLite, code that links against SQLite is |
| 5489 | ** permitted to use any of these routines. |
| 5490 | ** |
| 5491 | ** The SQLite source code contains multiple implementations |
| 5492 | ** of these mutex routines. An appropriate implementation |
| 5493 | ** is selected automatically at compile-time. ^(The following |
| 5494 | ** implementations are available in the SQLite core: |
| 5495 | ** |
| 5496 | ** <ul> |
| 5497 | ** <li> SQLITE_MUTEX_OS2 |
| 5498 | ** <li> SQLITE_MUTEX_PTHREADS |
| 5499 | ** <li> SQLITE_MUTEX_W32 |
| 5500 | ** <li> SQLITE_MUTEX_NOOP |
| 5501 | ** </ul>)^ |
| 5502 | ** |
| 5503 | ** ^The SQLITE_MUTEX_NOOP implementation is a set of routines |
| 5504 | ** that does no real locking and is appropriate for use in |
| 5505 | ** a single-threaded application. ^The SQLITE_MUTEX_OS2, |
| 5506 | ** SQLITE_MUTEX_PTHREADS, and SQLITE_MUTEX_W32 implementations |
| 5507 | ** are appropriate for use on OS/2, Unix, and Windows. |
| 5508 | ** |
| 5509 | ** ^(If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor |
| 5510 | ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex |
| 5511 | ** implementation is included with the library. In this case the |
| 5512 | ** application must supply a custom mutex implementation using the |
| 5513 | ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function |
| 5514 | ** before calling sqlite3_initialize() or any other public sqlite3_ |
| 5515 | ** function that calls sqlite3_initialize().)^ |
| 5516 | ** |
| 5517 | ** ^The sqlite3_mutex_alloc() routine allocates a new |
| 5518 | ** mutex and returns a pointer to it. ^If it returns NULL |
| 5519 | ** that means that a mutex could not be allocated. ^SQLite |
| 5520 | ** will unwind its stack and return an error. ^(The argument |
| 5521 | ** to sqlite3_mutex_alloc() is one of these integer constants: |
| 5522 | ** |
| 5523 | ** <ul> |
| 5524 | ** <li> SQLITE_MUTEX_FAST |
| 5525 | ** <li> SQLITE_MUTEX_RECURSIVE |
| 5526 | ** <li> SQLITE_MUTEX_STATIC_MASTER |
| 5527 | ** <li> SQLITE_MUTEX_STATIC_MEM |
| 5528 | ** <li> SQLITE_MUTEX_STATIC_MEM2 |
| 5529 | ** <li> SQLITE_MUTEX_STATIC_PRNG |
| 5530 | ** <li> SQLITE_MUTEX_STATIC_LRU |
| 5531 | ** <li> SQLITE_MUTEX_STATIC_LRU2 |
| 5532 | ** </ul>)^ |
| 5533 | ** |
| 5534 | ** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) |
| 5535 | ** cause sqlite3_mutex_alloc() to create |
| 5536 | ** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE |
| 5537 | ** is used but not necessarily so when SQLITE_MUTEX_FAST is used. |
| 5538 | ** The mutex implementation does not need to make a distinction |
| 5539 | ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does |
| 5540 | ** not want to. ^SQLite will only request a recursive mutex in |
| 5541 | ** cases where it really needs one. ^If a faster non-recursive mutex |
| 5542 | ** implementation is available on the host platform, the mutex subsystem |
| 5543 | ** might return such a mutex in response to SQLITE_MUTEX_FAST. |
| 5544 | ** |
| 5545 | ** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other |
| 5546 | ** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return |
| 5547 | ** a pointer to a static preexisting mutex. ^Six static mutexes are |
| 5548 | ** used by the current version of SQLite. Future versions of SQLite |
| 5549 | ** may add additional static mutexes. Static mutexes are for internal |
| 5550 | ** use by SQLite only. Applications that use SQLite mutexes should |
| 5551 | ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or |
| 5552 | ** SQLITE_MUTEX_RECURSIVE. |
| 5553 | ** |
| 5554 | ** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST |
| 5555 | ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() |
| 5556 | ** returns a different mutex on every call. ^But for the static |
| 5557 | ** mutex types, the same mutex is returned on every call that has |
| 5558 | ** the same type number. |
| 5559 | ** |
| 5560 | ** ^The sqlite3_mutex_free() routine deallocates a previously |
| 5561 | ** allocated dynamic mutex. ^SQLite is careful to deallocate every |
| 5562 | ** dynamic mutex that it allocates. The dynamic mutexes must not be in |
| 5563 | ** use when they are deallocated. Attempting to deallocate a static |
| 5564 | ** mutex results in undefined behavior. ^SQLite never deallocates |
| 5565 | ** a static mutex. |
| 5566 | ** |
| 5567 | ** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt |
| 5568 | ** to enter a mutex. ^If another thread is already within the mutex, |
| 5569 | ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return |
| 5570 | ** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK] |
| 5571 | ** upon successful entry. ^(Mutexes created using |
| 5572 | ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. |
| 5573 | ** In such cases the, |
| 5574 | ** mutex must be exited an equal number of times before another thread |
| 5575 | ** can enter.)^ ^(If the same thread tries to enter any other |
| 5576 | ** kind of mutex more than once, the behavior is undefined. |
| 5577 | ** SQLite will never exhibit |
| 5578 | ** such behavior in its own use of mutexes.)^ |
| 5579 | ** |
| 5580 | ** ^(Some systems (for example, Windows 95) do not support the operation |
| 5581 | ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() |
| 5582 | ** will always return SQLITE_BUSY. The SQLite core only ever uses |
| 5583 | ** sqlite3_mutex_try() as an optimization so this is acceptable behavior.)^ |
| 5584 | ** |
| 5585 | ** ^The sqlite3_mutex_leave() routine exits a mutex that was |
| 5586 | ** previously entered by the same thread. ^(The behavior |
| 5587 | ** is undefined if the mutex is not currently entered by the |
| 5588 | ** calling thread or is not currently allocated. SQLite will |
| 5589 | ** never do either.)^ |
| 5590 | ** |
| 5591 | ** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or |
| 5592 | ** sqlite3_mutex_leave() is a NULL pointer, then all three routines |
| 5593 | ** behave as no-ops. |
| 5594 | ** |
| 5595 | ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. |
| 5596 | */ |
| 5597 | SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int); |
| 5598 | SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*); |
| 5599 | SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*); |
| 5600 | SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*); |
| 5601 | SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*); |
| 5602 | |
| 5603 | /* |
| 5604 | ** CAPI3REF: Mutex Methods Object |
| 5605 | ** |
| 5606 | ** An instance of this structure defines the low-level routines |
| 5607 | ** used to allocate and use mutexes. |
| 5608 | ** |
| 5609 | ** Usually, the default mutex implementations provided by SQLite are |
| 5610 | ** sufficient, however the user has the option of substituting a custom |
| 5611 | ** implementation for specialized deployments or systems for which SQLite |
| 5612 | ** does not provide a suitable implementation. In this case, the user |
| 5613 | ** creates and populates an instance of this structure to pass |
| 5614 | ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option. |
| 5615 | ** Additionally, an instance of this structure can be used as an |
| 5616 | ** output variable when querying the system for the current mutex |
| 5617 | ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option. |
| 5618 | ** |
| 5619 | ** ^The xMutexInit method defined by this structure is invoked as |
| 5620 | ** part of system initialization by the sqlite3_initialize() function. |
| 5621 | ** ^The xMutexInit routine is called by SQLite exactly once for each |
| 5622 | ** effective call to [sqlite3_initialize()]. |
| 5623 | ** |
| 5624 | ** ^The xMutexEnd method defined by this structure is invoked as |
| 5625 | ** part of system shutdown by the sqlite3_shutdown() function. The |
| 5626 | ** implementation of this method is expected to release all outstanding |
| 5627 | ** resources obtained by the mutex methods implementation, especially |
| 5628 | ** those obtained by the xMutexInit method. ^The xMutexEnd() |
| 5629 | ** interface is invoked exactly once for each call to [sqlite3_shutdown()]. |
| 5630 | ** |
| 5631 | ** ^(The remaining seven methods defined by this structure (xMutexAlloc, |
| 5632 | ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and |
| 5633 | ** xMutexNotheld) implement the following interfaces (respectively): |
| 5634 | ** |
| 5635 | ** <ul> |
| 5636 | ** <li> [sqlite3_mutex_alloc()] </li> |
| 5637 | ** <li> [sqlite3_mutex_free()] </li> |
| 5638 | ** <li> [sqlite3_mutex_enter()] </li> |
| 5639 | ** <li> [sqlite3_mutex_try()] </li> |
| 5640 | ** <li> [sqlite3_mutex_leave()] </li> |
| 5641 | ** <li> [sqlite3_mutex_held()] </li> |
| 5642 | ** <li> [sqlite3_mutex_notheld()] </li> |
| 5643 | ** </ul>)^ |
| 5644 | ** |
| 5645 | ** The only difference is that the public sqlite3_XXX functions enumerated |
| 5646 | ** above silently ignore any invocations that pass a NULL pointer instead |
| 5647 | ** of a valid mutex handle. The implementations of the methods defined |
| 5648 | ** by this structure are not required to handle this case, the results |
| 5649 | ** of passing a NULL pointer instead of a valid mutex handle are undefined |
| 5650 | ** (i.e. it is acceptable to provide an implementation that segfaults if |
| 5651 | ** it is passed a NULL pointer). |
| 5652 | ** |
| 5653 | ** The xMutexInit() method must be threadsafe. ^It must be harmless to |
| 5654 | ** invoke xMutexInit() multiple times within the same process and without |
| 5655 | ** intervening calls to xMutexEnd(). Second and subsequent calls to |
| 5656 | ** xMutexInit() must be no-ops. |
| 5657 | ** |
| 5658 | ** ^xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()] |
| 5659 | ** and its associates). ^Similarly, xMutexAlloc() must not use SQLite memory |
| 5660 | ** allocation for a static mutex. ^However xMutexAlloc() may use SQLite |
| 5661 | ** memory allocation for a fast or recursive mutex. |
| 5662 | ** |
| 5663 | ** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is |
| 5664 | ** called, but only if the prior call to xMutexInit returned SQLITE_OK. |
| 5665 | ** If xMutexInit fails in any way, it is expected to clean up after itself |
| 5666 | ** prior to returning. |
| 5667 | */ |
| 5668 | typedef struct sqlite3_mutex_methods sqlite3_mutex_methods; |
| 5669 | struct sqlite3_mutex_methods { |
| 5670 | int (*xMutexInit)(void); |
| 5671 | int (*xMutexEnd)(void); |
| 5672 | sqlite3_mutex *(*xMutexAlloc)(int); |
| 5673 | void (*xMutexFree)(sqlite3_mutex *); |
| 5674 | void (*xMutexEnter)(sqlite3_mutex *); |
| 5675 | int (*xMutexTry)(sqlite3_mutex *); |
| 5676 | void (*xMutexLeave)(sqlite3_mutex *); |
| 5677 | int (*xMutexHeld)(sqlite3_mutex *); |
| 5678 | int (*xMutexNotheld)(sqlite3_mutex *); |
| 5679 | }; |
| 5680 | |
| 5681 | /* |
| 5682 | ** CAPI3REF: Mutex Verification Routines |
| 5683 | ** |
| 5684 | ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines |
| 5685 | ** are intended for use inside assert() statements. ^The SQLite core |
| 5686 | ** never uses these routines except inside an assert() and applications |
| 5687 | ** are advised to follow the lead of the core. ^The SQLite core only |
| 5688 | ** provides implementations for these routines when it is compiled |
| 5689 | ** with the SQLITE_DEBUG flag. ^External mutex implementations |
| 5690 | ** are only required to provide these routines if SQLITE_DEBUG is |
| 5691 | ** defined and if NDEBUG is not defined. |
| 5692 | ** |
| 5693 | ** ^These routines should return true if the mutex in their argument |
| 5694 | ** is held or not held, respectively, by the calling thread. |
| 5695 | ** |
| 5696 | ** ^The implementation is not required to provide versions of these |
| 5697 | ** routines that actually work. If the implementation does not provide working |
| 5698 | ** versions of these routines, it should at least provide stubs that always |
| 5699 | ** return true so that one does not get spurious assertion failures. |
| 5700 | ** |
| 5701 | ** ^If the argument to sqlite3_mutex_held() is a NULL pointer then |
| 5702 | ** the routine should return 1. This seems counter-intuitive since |
| 5703 | ** clearly the mutex cannot be held if it does not exist. But |
| 5704 | ** the reason the mutex does not exist is because the build is not |
| 5705 | ** using mutexes. And we do not want the assert() containing the |
| 5706 | ** call to sqlite3_mutex_held() to fail, so a non-zero return is |
| 5707 | ** the appropriate thing to do. ^The sqlite3_mutex_notheld() |
| 5708 | ** interface should also return 1 when given a NULL pointer. |
| 5709 | */ |
| 5710 | #ifndef NDEBUG |
| 5711 | SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*); |
| 5712 | SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*); |
| 5713 | #endif |
| 5714 | |
| 5715 | /* |
| 5716 | ** CAPI3REF: Mutex Types |
| 5717 | ** |
| 5718 | ** The [sqlite3_mutex_alloc()] interface takes a single argument |
| 5719 | ** which is one of these integer constants. |
| 5720 | ** |
| 5721 | ** The set of static mutexes may change from one SQLite release to the |
| 5722 | ** next. Applications that override the built-in mutex logic must be |
| 5723 | ** prepared to accommodate additional static mutexes. |
| 5724 | */ |
| 5725 | #define SQLITE_MUTEX_FAST 0 |
| 5726 | #define SQLITE_MUTEX_RECURSIVE 1 |
| 5727 | #define SQLITE_MUTEX_STATIC_MASTER 2 |
| 5728 | #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ |
| 5729 | #define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */ |
| 5730 | #define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */ |
| 5731 | #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */ |
| 5732 | #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ |
| 5733 | #define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */ |
| 5734 | #define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */ |
| 5735 | |
| 5736 | /* |
| 5737 | ** CAPI3REF: Retrieve the mutex for a database connection |
| 5738 | ** |
| 5739 | ** ^This interface returns a pointer the [sqlite3_mutex] object that |
| 5740 | ** serializes access to the [database connection] given in the argument |
| 5741 | ** when the [threading mode] is Serialized. |
| 5742 | ** ^If the [threading mode] is Single-thread or Multi-thread then this |
| 5743 | ** routine returns a NULL pointer. |
| 5744 | */ |
| 5745 | SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*); |
| 5746 | |
| 5747 | /* |
| 5748 | ** CAPI3REF: Low-Level Control Of Database Files |
| 5749 | ** |
| 5750 | ** ^The [sqlite3_file_control()] interface makes a direct call to the |
| 5751 | ** xFileControl method for the [sqlite3_io_methods] object associated |
| 5752 | ** with a particular database identified by the second argument. ^The |
| 5753 | ** name of the database is "main" for the main database or "temp" for the |
| 5754 | ** TEMP database, or the name that appears after the AS keyword for |
| 5755 | ** databases that are added using the [ATTACH] SQL command. |
| 5756 | ** ^A NULL pointer can be used in place of "main" to refer to the |
| 5757 | ** main database file. |
| 5758 | ** ^The third and fourth parameters to this routine |
| 5759 | ** are passed directly through to the second and third parameters of |
| 5760 | ** the xFileControl method. ^The return value of the xFileControl |
| 5761 | ** method becomes the return value of this routine. |
| 5762 | ** |
| 5763 | ** ^The SQLITE_FCNTL_FILE_POINTER value for the op parameter causes |
| 5764 | ** a pointer to the underlying [sqlite3_file] object to be written into |
| 5765 | ** the space pointed to by the 4th parameter. ^The SQLITE_FCNTL_FILE_POINTER |
| 5766 | ** case is a short-circuit path which does not actually invoke the |
| 5767 | ** underlying sqlite3_io_methods.xFileControl method. |
| 5768 | ** |
| 5769 | ** ^If the second parameter (zDbName) does not match the name of any |
| 5770 | ** open database file, then SQLITE_ERROR is returned. ^This error |
| 5771 | ** code is not remembered and will not be recalled by [sqlite3_errcode()] |
| 5772 | ** or [sqlite3_errmsg()]. The underlying xFileControl method might |
| 5773 | ** also return SQLITE_ERROR. There is no way to distinguish between |
| 5774 | ** an incorrect zDbName and an SQLITE_ERROR return from the underlying |
| 5775 | ** xFileControl method. |
| 5776 | ** |
| 5777 | ** See also: [SQLITE_FCNTL_LOCKSTATE] |
| 5778 | */ |
| 5779 | SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*); |
| 5780 | |
| 5781 | /* |
| 5782 | ** CAPI3REF: Testing Interface |
| 5783 | ** |
| 5784 | ** ^The sqlite3_test_control() interface is used to read out internal |
| 5785 | ** state of SQLite and to inject faults into SQLite for testing |
| 5786 | ** purposes. ^The first parameter is an operation code that determines |
| 5787 | ** the number, meaning, and operation of all subsequent parameters. |
| 5788 | ** |
| 5789 | ** This interface is not for use by applications. It exists solely |
| 5790 | ** for verifying the correct operation of the SQLite library. Depending |
| 5791 | ** on how the SQLite library is compiled, this interface might not exist. |
| 5792 | ** |
| 5793 | ** The details of the operation codes, their meanings, the parameters |
| 5794 | ** they take, and what they do are all subject to change without notice. |
| 5795 | ** Unlike most of the SQLite API, this function is not guaranteed to |
| 5796 | ** operate consistently from one release to the next. |
| 5797 | */ |
| 5798 | SQLITE_API int sqlite3_test_control(int op, ...); |
| 5799 | |
| 5800 | /* |
| 5801 | ** CAPI3REF: Testing Interface Operation Codes |
| 5802 | ** |
| 5803 | ** These constants are the valid operation code parameters used |
| 5804 | ** as the first argument to [sqlite3_test_control()]. |
| 5805 | ** |
| 5806 | ** These parameters and their meanings are subject to change |
| 5807 | ** without notice. These values are for testing purposes only. |
| 5808 | ** Applications should not use any of these parameters or the |
| 5809 | ** [sqlite3_test_control()] interface. |
| 5810 | */ |
| 5811 | #define SQLITE_TESTCTRL_FIRST 5 |
| 5812 | #define SQLITE_TESTCTRL_PRNG_SAVE 5 |
| 5813 | #define SQLITE_TESTCTRL_PRNG_RESTORE 6 |
| 5814 | #define SQLITE_TESTCTRL_PRNG_RESET 7 |
| 5815 | #define SQLITE_TESTCTRL_BITVEC_TEST 8 |
| 5816 | #define SQLITE_TESTCTRL_FAULT_INSTALL 9 |
| 5817 | #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10 |
| 5818 | #define SQLITE_TESTCTRL_PENDING_BYTE 11 |
| 5819 | #define SQLITE_TESTCTRL_ASSERT 12 |
| 5820 | #define SQLITE_TESTCTRL_ALWAYS 13 |
| 5821 | #define SQLITE_TESTCTRL_RESERVE 14 |
| 5822 | #define SQLITE_TESTCTRL_OPTIMIZATIONS 15 |
| 5823 | #define SQLITE_TESTCTRL_ISKEYWORD 16 |
| 5824 | #define SQLITE_TESTCTRL_SCRATCHMALLOC 17 |
| 5825 | #define SQLITE_TESTCTRL_LOCALTIME_FAULT 18 |
| 5826 | #define SQLITE_TESTCTRL_EXPLAIN_STMT 19 |
| 5827 | #define SQLITE_TESTCTRL_LAST 19 |
| 5828 | |
| 5829 | /* |
| 5830 | ** CAPI3REF: SQLite Runtime Status |
| 5831 | ** |
| 5832 | ** ^This interface is used to retrieve runtime status information |
| 5833 | ** about the performance of SQLite, and optionally to reset various |
| 5834 | ** highwater marks. ^The first argument is an integer code for |
| 5835 | ** the specific parameter to measure. ^(Recognized integer codes |
| 5836 | ** are of the form [status parameters | SQLITE_STATUS_...].)^ |
| 5837 | ** ^The current value of the parameter is returned into *pCurrent. |
| 5838 | ** ^The highest recorded value is returned in *pHighwater. ^If the |
| 5839 | ** resetFlag is true, then the highest record value is reset after |
| 5840 | ** *pHighwater is written. ^(Some parameters do not record the highest |
| 5841 | ** value. For those parameters |
| 5842 | ** nothing is written into *pHighwater and the resetFlag is ignored.)^ |
| 5843 | ** ^(Other parameters record only the highwater mark and not the current |
| 5844 | ** value. For these latter parameters nothing is written into *pCurrent.)^ |
| 5845 | ** |
| 5846 | ** ^The sqlite3_status() routine returns SQLITE_OK on success and a |
| 5847 | ** non-zero [error code] on failure. |
| 5848 | ** |
| 5849 | ** This routine is threadsafe but is not atomic. This routine can be |
| 5850 | ** called while other threads are running the same or different SQLite |
| 5851 | ** interfaces. However the values returned in *pCurrent and |
| 5852 | ** *pHighwater reflect the status of SQLite at different points in time |
| 5853 | ** and it is possible that another thread might change the parameter |
| 5854 | ** in between the times when *pCurrent and *pHighwater are written. |
| 5855 | ** |
| 5856 | ** See also: [sqlite3_db_status()] |
| 5857 | */ |
| 5858 | SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag); |
| 5859 | |
| 5860 | |
| 5861 | /* |
| 5862 | ** CAPI3REF: Status Parameters |
| 5863 | ** KEYWORDS: {status parameters} |
| 5864 | ** |
| 5865 | ** These integer constants designate various run-time status parameters |
| 5866 | ** that can be returned by [sqlite3_status()]. |
| 5867 | ** |
| 5868 | ** <dl> |
| 5869 | ** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt> |
| 5870 | ** <dd>This parameter is the current amount of memory checked out |
| 5871 | ** using [sqlite3_malloc()], either directly or indirectly. The |
| 5872 | ** figure includes calls made to [sqlite3_malloc()] by the application |
| 5873 | ** and internal memory usage by the SQLite library. Scratch memory |
| 5874 | ** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache |
| 5875 | ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in |
| 5876 | ** this parameter. The amount returned is the sum of the allocation |
| 5877 | ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^ |
| 5878 | ** |
| 5879 | ** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt> |
| 5880 | ** <dd>This parameter records the largest memory allocation request |
| 5881 | ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their |
| 5882 | ** internal equivalents). Only the value returned in the |
| 5883 | ** *pHighwater parameter to [sqlite3_status()] is of interest. |
| 5884 | ** The value written into the *pCurrent parameter is undefined.</dd>)^ |
| 5885 | ** |
| 5886 | ** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt> |
| 5887 | ** <dd>This parameter records the number of separate memory allocations |
| 5888 | ** currently checked out.</dd>)^ |
| 5889 | ** |
| 5890 | ** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt> |
| 5891 | ** <dd>This parameter returns the number of pages used out of the |
| 5892 | ** [pagecache memory allocator] that was configured using |
| 5893 | ** [SQLITE_CONFIG_PAGECACHE]. The |
| 5894 | ** value returned is in pages, not in bytes.</dd>)^ |
| 5895 | ** |
| 5896 | ** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] |
| 5897 | ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt> |
| 5898 | ** <dd>This parameter returns the number of bytes of page cache |
| 5899 | ** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE] |
| 5900 | ** buffer and where forced to overflow to [sqlite3_malloc()]. The |
| 5901 | ** returned value includes allocations that overflowed because they |
| 5902 | ** where too large (they were larger than the "sz" parameter to |
| 5903 | ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because |
| 5904 | ** no space was left in the page cache.</dd>)^ |
| 5905 | ** |
| 5906 | ** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt> |
| 5907 | ** <dd>This parameter records the largest memory allocation request |
| 5908 | ** handed to [pagecache memory allocator]. Only the value returned in the |
| 5909 | ** *pHighwater parameter to [sqlite3_status()] is of interest. |
| 5910 | ** The value written into the *pCurrent parameter is undefined.</dd>)^ |
| 5911 | ** |
| 5912 | ** [[SQLITE_STATUS_SCRATCH_USED]] ^(<dt>SQLITE_STATUS_SCRATCH_USED</dt> |
| 5913 | ** <dd>This parameter returns the number of allocations used out of the |
| 5914 | ** [scratch memory allocator] configured using |
| 5915 | ** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not |
| 5916 | ** in bytes. Since a single thread may only have one scratch allocation |
| 5917 | ** outstanding at time, this parameter also reports the number of threads |
| 5918 | ** using scratch memory at the same time.</dd>)^ |
| 5919 | ** |
| 5920 | ** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt> |
| 5921 | ** <dd>This parameter returns the number of bytes of scratch memory |
| 5922 | ** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH] |
| 5923 | ** buffer and where forced to overflow to [sqlite3_malloc()]. The values |
| 5924 | ** returned include overflows because the requested allocation was too |
| 5925 | ** larger (that is, because the requested allocation was larger than the |
| 5926 | ** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer |
| 5927 | ** slots were available. |
| 5928 | ** </dd>)^ |
| 5929 | ** |
| 5930 | ** [[SQLITE_STATUS_SCRATCH_SIZE]] ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt> |
| 5931 | ** <dd>This parameter records the largest memory allocation request |
| 5932 | ** handed to [scratch memory allocator]. Only the value returned in the |
| 5933 | ** *pHighwater parameter to [sqlite3_status()] is of interest. |
| 5934 | ** The value written into the *pCurrent parameter is undefined.</dd>)^ |
| 5935 | ** |
| 5936 | ** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt> |
| 5937 | ** <dd>This parameter records the deepest parser stack. It is only |
| 5938 | ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^ |
| 5939 | ** </dl> |
| 5940 | ** |
| 5941 | ** New status parameters may be added from time to time. |
| 5942 | */ |
| 5943 | #define SQLITE_STATUS_MEMORY_USED 0 |
| 5944 | #define SQLITE_STATUS_PAGECACHE_USED 1 |
| 5945 | #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2 |
| 5946 | #define SQLITE_STATUS_SCRATCH_USED 3 |
| 5947 | #define SQLITE_STATUS_SCRATCH_OVERFLOW 4 |
| 5948 | #define SQLITE_STATUS_MALLOC_SIZE 5 |
| 5949 | #define SQLITE_STATUS_PARSER_STACK 6 |
| 5950 | #define SQLITE_STATUS_PAGECACHE_SIZE 7 |
| 5951 | #define SQLITE_STATUS_SCRATCH_SIZE 8 |
| 5952 | #define SQLITE_STATUS_MALLOC_COUNT 9 |
| 5953 | |
| 5954 | /* |
| 5955 | ** CAPI3REF: Database Connection Status |
| 5956 | ** |
| 5957 | ** ^This interface is used to retrieve runtime status information |
| 5958 | ** about a single [database connection]. ^The first argument is the |
| 5959 | ** database connection object to be interrogated. ^The second argument |
| 5960 | ** is an integer constant, taken from the set of |
| 5961 | ** [SQLITE_DBSTATUS options], that |
| 5962 | ** determines the parameter to interrogate. The set of |
| 5963 | ** [SQLITE_DBSTATUS options] is likely |
| 5964 | ** to grow in future releases of SQLite. |
| 5965 | ** |
| 5966 | ** ^The current value of the requested parameter is written into *pCur |
| 5967 | ** and the highest instantaneous value is written into *pHiwtr. ^If |
| 5968 | ** the resetFlg is true, then the highest instantaneous value is |
| 5969 | ** reset back down to the current value. |
| 5970 | ** |
| 5971 | ** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a |
| 5972 | ** non-zero [error code] on failure. |
| 5973 | ** |
| 5974 | ** See also: [sqlite3_status()] and [sqlite3_stmt_status()]. |
| 5975 | */ |
| 5976 | SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg); |
| 5977 | |
| 5978 | /* |
| 5979 | ** CAPI3REF: Status Parameters for database connections |
| 5980 | ** KEYWORDS: {SQLITE_DBSTATUS options} |
| 5981 | ** |
| 5982 | ** These constants are the available integer "verbs" that can be passed as |
| 5983 | ** the second argument to the [sqlite3_db_status()] interface. |
| 5984 | ** |
| 5985 | ** New verbs may be added in future releases of SQLite. Existing verbs |
| 5986 | ** might be discontinued. Applications should check the return code from |
| 5987 | ** [sqlite3_db_status()] to make sure that the call worked. |
| 5988 | ** The [sqlite3_db_status()] interface will return a non-zero error code |
| 5989 | ** if a discontinued or unsupported verb is invoked. |
| 5990 | ** |
| 5991 | ** <dl> |
| 5992 | ** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt> |
| 5993 | ** <dd>This parameter returns the number of lookaside memory slots currently |
| 5994 | ** checked out.</dd>)^ |
| 5995 | ** |
| 5996 | ** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt> |
| 5997 | ** <dd>This parameter returns the number malloc attempts that were |
| 5998 | ** satisfied using lookaside memory. Only the high-water value is meaningful; |
| 5999 | ** the current value is always zero.)^ |
| 6000 | ** |
| 6001 | ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]] |
| 6002 | ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt> |
| 6003 | ** <dd>This parameter returns the number malloc attempts that might have |
| 6004 | ** been satisfied using lookaside memory but failed due to the amount of |
| 6005 | ** memory requested being larger than the lookaside slot size. |
| 6006 | ** Only the high-water value is meaningful; |
| 6007 | ** the current value is always zero.)^ |
| 6008 | ** |
| 6009 | ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]] |
| 6010 | ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt> |
| 6011 | ** <dd>This parameter returns the number malloc attempts that might have |
| 6012 | ** been satisfied using lookaside memory but failed due to all lookaside |
| 6013 | ** memory already being in use. |
| 6014 | ** Only the high-water value is meaningful; |
| 6015 | ** the current value is always zero.)^ |
| 6016 | ** |
| 6017 | ** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt> |
| 6018 | ** <dd>This parameter returns the approximate number of of bytes of heap |
| 6019 | ** memory used by all pager caches associated with the database connection.)^ |
| 6020 | ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0. |
| 6021 | ** |
| 6022 | ** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt> |
| 6023 | ** <dd>This parameter returns the approximate number of of bytes of heap |
| 6024 | ** memory used to store the schema for all databases associated |
| 6025 | ** with the connection - main, temp, and any [ATTACH]-ed databases.)^ |
| 6026 | ** ^The full amount of memory used by the schemas is reported, even if the |
| 6027 | ** schema memory is shared with other database connections due to |
| 6028 | ** [shared cache mode] being enabled. |
| 6029 | ** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0. |
| 6030 | ** |
| 6031 | ** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt> |
| 6032 | ** <dd>This parameter returns the approximate number of of bytes of heap |
| 6033 | ** and lookaside memory used by all prepared statements associated with |
| 6034 | ** the database connection.)^ |
| 6035 | ** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0. |
| 6036 | ** </dd> |
| 6037 | ** |
| 6038 | ** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt> |
| 6039 | ** <dd>This parameter returns the number of pager cache hits that have |
| 6040 | ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT |
| 6041 | ** is always 0. |
| 6042 | ** </dd> |
| 6043 | ** |
| 6044 | ** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt> |
| 6045 | ** <dd>This parameter returns the number of pager cache misses that have |
| 6046 | ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS |
| 6047 | ** is always 0. |
| 6048 | ** </dd> |
| 6049 | ** |
| 6050 | ** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt> |
| 6051 | ** <dd>This parameter returns the number of dirty cache entries that have |
| 6052 | ** been written to disk. Specifically, the number of pages written to the |
| 6053 | ** wal file in wal mode databases, or the number of pages written to the |
| 6054 | ** database file in rollback mode databases. Any pages written as part of |
| 6055 | ** transaction rollback or database recovery operations are not included. |
| 6056 | ** If an IO or other error occurs while writing a page to disk, the effect |
| 6057 | ** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The |
| 6058 | ** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0. |
| 6059 | ** </dd> |
| 6060 | ** </dl> |
| 6061 | */ |
| 6062 | #define SQLITE_DBSTATUS_LOOKASIDE_USED 0 |
| 6063 | #define SQLITE_DBSTATUS_CACHE_USED 1 |
| 6064 | #define SQLITE_DBSTATUS_SCHEMA_USED 2 |
| 6065 | #define SQLITE_DBSTATUS_STMT_USED 3 |
| 6066 | #define SQLITE_DBSTATUS_LOOKASIDE_HIT 4 |
| 6067 | #define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5 |
| 6068 | #define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6 |
| 6069 | #define SQLITE_DBSTATUS_CACHE_HIT 7 |
| 6070 | #define SQLITE_DBSTATUS_CACHE_MISS 8 |
| 6071 | #define SQLITE_DBSTATUS_CACHE_WRITE 9 |
| 6072 | #define SQLITE_DBSTATUS_MAX 9 /* Largest defined DBSTATUS */ |
| 6073 | |
| 6074 | |
| 6075 | /* |
| 6076 | ** CAPI3REF: Prepared Statement Status |
| 6077 | ** |
| 6078 | ** ^(Each prepared statement maintains various |
| 6079 | ** [SQLITE_STMTSTATUS counters] that measure the number |
| 6080 | ** of times it has performed specific operations.)^ These counters can |
| 6081 | ** be used to monitor the performance characteristics of the prepared |
| 6082 | ** statements. For example, if the number of table steps greatly exceeds |
| 6083 | ** the number of table searches or result rows, that would tend to indicate |
| 6084 | ** that the prepared statement is using a full table scan rather than |
| 6085 | ** an index. |
| 6086 | ** |
| 6087 | ** ^(This interface is used to retrieve and reset counter values from |
| 6088 | ** a [prepared statement]. The first argument is the prepared statement |
| 6089 | ** object to be interrogated. The second argument |
| 6090 | ** is an integer code for a specific [SQLITE_STMTSTATUS counter] |
| 6091 | ** to be interrogated.)^ |
| 6092 | ** ^The current value of the requested counter is returned. |
| 6093 | ** ^If the resetFlg is true, then the counter is reset to zero after this |
| 6094 | ** interface call returns. |
| 6095 | ** |
| 6096 | ** See also: [sqlite3_status()] and [sqlite3_db_status()]. |
| 6097 | */ |
| 6098 | SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg); |
| 6099 | |
| 6100 | /* |
| 6101 | ** CAPI3REF: Status Parameters for prepared statements |
| 6102 | ** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters} |
| 6103 | ** |
| 6104 | ** These preprocessor macros define integer codes that name counter |
| 6105 | ** values associated with the [sqlite3_stmt_status()] interface. |
| 6106 | ** The meanings of the various counters are as follows: |
| 6107 | ** |
| 6108 | ** <dl> |
| 6109 | ** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt> |
| 6110 | ** <dd>^This is the number of times that SQLite has stepped forward in |
| 6111 | ** a table as part of a full table scan. Large numbers for this counter |
| 6112 | ** may indicate opportunities for performance improvement through |
| 6113 | ** careful use of indices.</dd> |
| 6114 | ** |
| 6115 | ** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt> |
| 6116 | ** <dd>^This is the number of sort operations that have occurred. |
| 6117 | ** A non-zero value in this counter may indicate an opportunity to |
| 6118 | ** improvement performance through careful use of indices.</dd> |
| 6119 | ** |
| 6120 | ** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt> |
| 6121 | ** <dd>^This is the number of rows inserted into transient indices that |
| 6122 | ** were created automatically in order to help joins run faster. |
| 6123 | ** A non-zero value in this counter may indicate an opportunity to |
| 6124 | ** improvement performance by adding permanent indices that do not |
| 6125 | ** need to be reinitialized each time the statement is run.</dd> |
| 6126 | ** </dl> |
| 6127 | */ |
| 6128 | #define SQLITE_STMTSTATUS_FULLSCAN_STEP 1 |
| 6129 | #define SQLITE_STMTSTATUS_SORT 2 |
| 6130 | #define SQLITE_STMTSTATUS_AUTOINDEX 3 |
| 6131 | |
| 6132 | /* |
| 6133 | ** CAPI3REF: Custom Page Cache Object |
| 6134 | ** |
| 6135 | ** The sqlite3_pcache type is opaque. It is implemented by |
| 6136 | ** the pluggable module. The SQLite core has no knowledge of |
| 6137 | ** its size or internal structure and never deals with the |
| 6138 | ** sqlite3_pcache object except by holding and passing pointers |
| 6139 | ** to the object. |
| 6140 | ** |
| 6141 | ** See [sqlite3_pcache_methods2] for additional information. |
| 6142 | */ |
| 6143 | typedef struct sqlite3_pcache sqlite3_pcache; |
| 6144 | |
| 6145 | /* |
| 6146 | ** CAPI3REF: Custom Page Cache Object |
| 6147 | ** |
| 6148 | ** The sqlite3_pcache_page object represents a single page in the |
| 6149 | ** page cache. The page cache will allocate instances of this |
| 6150 | ** object. Various methods of the page cache use pointers to instances |
| 6151 | ** of this object as parameters or as their return value. |
| 6152 | ** |
| 6153 | ** See [sqlite3_pcache_methods2] for additional information. |
| 6154 | */ |
| 6155 | typedef struct sqlite3_pcache_page sqlite3_pcache_page; |
| 6156 | struct sqlite3_pcache_page { |
| 6157 | void *pBuf; /* The content of the page */ |
| 6158 | void *pExtra; /* Extra information associated with the page */ |
| 6159 | }; |
| 6160 | |
| 6161 | /* |
| 6162 | ** CAPI3REF: Application Defined Page Cache. |
| 6163 | ** KEYWORDS: {page cache} |
| 6164 | ** |
| 6165 | ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can |
| 6166 | ** register an alternative page cache implementation by passing in an |
| 6167 | ** instance of the sqlite3_pcache_methods2 structure.)^ |
| 6168 | ** In many applications, most of the heap memory allocated by |
| 6169 | ** SQLite is used for the page cache. |
| 6170 | ** By implementing a |
| 6171 | ** custom page cache using this API, an application can better control |
| 6172 | ** the amount of memory consumed by SQLite, the way in which |
| 6173 | ** that memory is allocated and released, and the policies used to |
| 6174 | ** determine exactly which parts of a database file are cached and for |
| 6175 | ** how long. |
| 6176 | ** |
| 6177 | ** The alternative page cache mechanism is an |
| 6178 | ** extreme measure that is only needed by the most demanding applications. |
| 6179 | ** The built-in page cache is recommended for most uses. |
| 6180 | ** |
| 6181 | ** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an |
| 6182 | ** internal buffer by SQLite within the call to [sqlite3_config]. Hence |
| 6183 | ** the application may discard the parameter after the call to |
| 6184 | ** [sqlite3_config()] returns.)^ |
| 6185 | ** |
| 6186 | ** [[the xInit() page cache method]] |
| 6187 | ** ^(The xInit() method is called once for each effective |
| 6188 | ** call to [sqlite3_initialize()])^ |
| 6189 | ** (usually only once during the lifetime of the process). ^(The xInit() |
| 6190 | ** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^ |
| 6191 | ** The intent of the xInit() method is to set up global data structures |
| 6192 | ** required by the custom page cache implementation. |
| 6193 | ** ^(If the xInit() method is NULL, then the |
| 6194 | ** built-in default page cache is used instead of the application defined |
| 6195 | ** page cache.)^ |
| 6196 | ** |
| 6197 | ** [[the xShutdown() page cache method]] |
| 6198 | ** ^The xShutdown() method is called by [sqlite3_shutdown()]. |
| 6199 | ** It can be used to clean up |
| 6200 | ** any outstanding resources before process shutdown, if required. |
| 6201 | ** ^The xShutdown() method may be NULL. |
| 6202 | ** |
| 6203 | ** ^SQLite automatically serializes calls to the xInit method, |
| 6204 | ** so the xInit method need not be threadsafe. ^The |
| 6205 | ** xShutdown method is only called from [sqlite3_shutdown()] so it does |
| 6206 | ** not need to be threadsafe either. All other methods must be threadsafe |
| 6207 | ** in multithreaded applications. |
| 6208 | ** |
| 6209 | ** ^SQLite will never invoke xInit() more than once without an intervening |
| 6210 | ** call to xShutdown(). |
| 6211 | ** |
| 6212 | ** [[the xCreate() page cache methods]] |
| 6213 | ** ^SQLite invokes the xCreate() method to construct a new cache instance. |
| 6214 | ** SQLite will typically create one cache instance for each open database file, |
| 6215 | ** though this is not guaranteed. ^The |
| 6216 | ** first parameter, szPage, is the size in bytes of the pages that must |
| 6217 | ** be allocated by the cache. ^szPage will always a power of two. ^The |
| 6218 | ** second parameter szExtra is a number of bytes of extra storage |
| 6219 | ** associated with each page cache entry. ^The szExtra parameter will |
| 6220 | ** a number less than 250. SQLite will use the |
| 6221 | ** extra szExtra bytes on each page to store metadata about the underlying |
| 6222 | ** database page on disk. The value passed into szExtra depends |
| 6223 | ** on the SQLite version, the target platform, and how SQLite was compiled. |
| 6224 | ** ^The third argument to xCreate(), bPurgeable, is true if the cache being |
| 6225 | ** created will be used to cache database pages of a file stored on disk, or |
| 6226 | ** false if it is used for an in-memory database. The cache implementation |
| 6227 | ** does not have to do anything special based with the value of bPurgeable; |
| 6228 | ** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will |
| 6229 | ** never invoke xUnpin() except to deliberately delete a page. |
| 6230 | ** ^In other words, calls to xUnpin() on a cache with bPurgeable set to |
| 6231 | ** false will always have the "discard" flag set to true. |
| 6232 | ** ^Hence, a cache created with bPurgeable false will |
| 6233 | ** never contain any unpinned pages. |
| 6234 | ** |
| 6235 | ** [[the xCachesize() page cache method]] |
| 6236 | ** ^(The xCachesize() method may be called at any time by SQLite to set the |
| 6237 | ** suggested maximum cache-size (number of pages stored by) the cache |
| 6238 | ** instance passed as the first argument. This is the value configured using |
| 6239 | ** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable |
| 6240 | ** parameter, the implementation is not required to do anything with this |
| 6241 | ** value; it is advisory only. |
| 6242 | ** |
| 6243 | ** [[the xPagecount() page cache methods]] |
| 6244 | ** The xPagecount() method must return the number of pages currently |
| 6245 | ** stored in the cache, both pinned and unpinned. |
| 6246 | ** |
| 6247 | ** [[the xFetch() page cache methods]] |
| 6248 | ** The xFetch() method locates a page in the cache and returns a pointer to |
| 6249 | ** an sqlite3_pcache_page object associated with that page, or a NULL pointer. |
| 6250 | ** The pBuf element of the returned sqlite3_pcache_page object will be a |
| 6251 | ** pointer to a buffer of szPage bytes used to store the content of a |
| 6252 | ** single database page. The pExtra element of sqlite3_pcache_page will be |
| 6253 | ** a pointer to the szExtra bytes of extra storage that SQLite has requested |
| 6254 | ** for each entry in the page cache. |
| 6255 | ** |
| 6256 | ** The page to be fetched is determined by the key. ^The minimum key value |
| 6257 | ** is 1. After it has been retrieved using xFetch, the page is considered |
| 6258 | ** to be "pinned". |
| 6259 | ** |
| 6260 | ** If the requested page is already in the page cache, then the page cache |
| 6261 | ** implementation must return a pointer to the page buffer with its content |
| 6262 | ** intact. If the requested page is not already in the cache, then the |
| 6263 | ** cache implementation should use the value of the createFlag |
| 6264 | ** parameter to help it determined what action to take: |
| 6265 | ** |
| 6266 | ** <table border=1 width=85% align=center> |
| 6267 | ** <tr><th> createFlag <th> Behaviour when page is not already in cache |
| 6268 | ** <tr><td> 0 <td> Do not allocate a new page. Return NULL. |
| 6269 | ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so. |
| 6270 | ** Otherwise return NULL. |
| 6271 | ** <tr><td> 2 <td> Make every effort to allocate a new page. Only return |
| 6272 | ** NULL if allocating a new page is effectively impossible. |
| 6273 | ** </table> |
| 6274 | ** |
| 6275 | ** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite |
| 6276 | ** will only use a createFlag of 2 after a prior call with a createFlag of 1 |
| 6277 | ** failed.)^ In between the to xFetch() calls, SQLite may |
| 6278 | ** attempt to unpin one or more cache pages by spilling the content of |
| 6279 | ** pinned pages to disk and synching the operating system disk cache. |
| 6280 | ** |
| 6281 | ** [[the xUnpin() page cache method]] |
| 6282 | ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page |
| 6283 | ** as its second argument. If the third parameter, discard, is non-zero, |
| 6284 | ** then the page must be evicted from the cache. |
| 6285 | ** ^If the discard parameter is |
| 6286 | ** zero, then the page may be discarded or retained at the discretion of |
| 6287 | ** page cache implementation. ^The page cache implementation |
| 6288 | ** may choose to evict unpinned pages at any time. |
| 6289 | ** |
| 6290 | ** The cache must not perform any reference counting. A single |
| 6291 | ** call to xUnpin() unpins the page regardless of the number of prior calls |
| 6292 | ** to xFetch(). |
| 6293 | ** |
| 6294 | ** [[the xRekey() page cache methods]] |
| 6295 | ** The xRekey() method is used to change the key value associated with the |
| 6296 | ** page passed as the second argument. If the cache |
| 6297 | ** previously contains an entry associated with newKey, it must be |
| 6298 | ** discarded. ^Any prior cache entry associated with newKey is guaranteed not |
| 6299 | ** to be pinned. |
| 6300 | ** |
| 6301 | ** When SQLite calls the xTruncate() method, the cache must discard all |
| 6302 | ** existing cache entries with page numbers (keys) greater than or equal |
| 6303 | ** to the value of the iLimit parameter passed to xTruncate(). If any |
| 6304 | ** of these pages are pinned, they are implicitly unpinned, meaning that |
| 6305 | ** they can be safely discarded. |
| 6306 | ** |
| 6307 | ** [[the xDestroy() page cache method]] |
| 6308 | ** ^The xDestroy() method is used to delete a cache allocated by xCreate(). |
| 6309 | ** All resources associated with the specified cache should be freed. ^After |
| 6310 | ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*] |
| 6311 | ** handle invalid, and will not use it with any other sqlite3_pcache_methods2 |
| 6312 | ** functions. |
| 6313 | ** |
| 6314 | ** [[the xShrink() page cache method]] |
| 6315 | ** ^SQLite invokes the xShrink() method when it wants the page cache to |
| 6316 | ** free up as much of heap memory as possible. The page cache implementation |
| 6317 | ** is not obligated to free any memory, but well-behaved implementations should |
| 6318 | ** do their best. |
| 6319 | */ |
| 6320 | typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2; |
| 6321 | struct sqlite3_pcache_methods2 { |
| 6322 | int iVersion; |
| 6323 | void *pArg; |
| 6324 | int (*xInit)(void*); |
| 6325 | void (*xShutdown)(void*); |
| 6326 | sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable); |
| 6327 | void (*xCachesize)(sqlite3_pcache*, int nCachesize); |
| 6328 | int (*xPagecount)(sqlite3_pcache*); |
| 6329 | sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); |
| 6330 | void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard); |
| 6331 | void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*, |
| 6332 | unsigned oldKey, unsigned newKey); |
| 6333 | void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); |
| 6334 | void (*xDestroy)(sqlite3_pcache*); |
| 6335 | void (*xShrink)(sqlite3_pcache*); |
| 6336 | }; |
| 6337 | |
| 6338 | /* |
| 6339 | ** This is the obsolete pcache_methods object that has now been replaced |
| 6340 | ** by sqlite3_pcache_methods2. This object is not used by SQLite. It is |
| 6341 | ** retained in the header file for backwards compatibility only. |
| 6342 | */ |
| 6343 | typedef struct sqlite3_pcache_methods sqlite3_pcache_methods; |
| 6344 | struct sqlite3_pcache_methods { |
| 6345 | void *pArg; |
| 6346 | int (*xInit)(void*); |
| 6347 | void (*xShutdown)(void*); |
| 6348 | sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable); |
| 6349 | void (*xCachesize)(sqlite3_pcache*, int nCachesize); |
| 6350 | int (*xPagecount)(sqlite3_pcache*); |
| 6351 | void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); |
| 6352 | void (*xUnpin)(sqlite3_pcache*, void*, int discard); |
| 6353 | void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey); |
| 6354 | void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); |
| 6355 | void (*xDestroy)(sqlite3_pcache*); |
| 6356 | }; |
| 6357 | |
| 6358 | |
| 6359 | /* |
| 6360 | ** CAPI3REF: Online Backup Object |
| 6361 | ** |
| 6362 | ** The sqlite3_backup object records state information about an ongoing |
| 6363 | ** online backup operation. ^The sqlite3_backup object is created by |
| 6364 | ** a call to [sqlite3_backup_init()] and is destroyed by a call to |
| 6365 | ** [sqlite3_backup_finish()]. |
| 6366 | ** |
| 6367 | ** See Also: [Using the SQLite Online Backup API] |
| 6368 | */ |
| 6369 | typedef struct sqlite3_backup sqlite3_backup; |
| 6370 | |
| 6371 | /* |
| 6372 | ** CAPI3REF: Online Backup API. |
| 6373 | ** |
| 6374 | ** The backup API copies the content of one database into another. |
| 6375 | ** It is useful either for creating backups of databases or |
| 6376 | ** for copying in-memory databases to or from persistent files. |
| 6377 | ** |
| 6378 | ** See Also: [Using the SQLite Online Backup API] |
| 6379 | ** |
| 6380 | ** ^SQLite holds a write transaction open on the destination database file |
| 6381 | ** for the duration of the backup operation. |
| 6382 | ** ^The source database is read-locked only while it is being read; |
| 6383 | ** it is not locked continuously for the entire backup operation. |
| 6384 | ** ^Thus, the backup may be performed on a live source database without |
| 6385 | ** preventing other database connections from |
| 6386 | ** reading or writing to the source database while the backup is underway. |
| 6387 | ** |
| 6388 | ** ^(To perform a backup operation: |
| 6389 | ** <ol> |
| 6390 | ** <li><b>sqlite3_backup_init()</b> is called once to initialize the |
| 6391 | ** backup, |
| 6392 | ** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer |
| 6393 | ** the data between the two databases, and finally |
| 6394 | ** <li><b>sqlite3_backup_finish()</b> is called to release all resources |
| 6395 | ** associated with the backup operation. |
| 6396 | ** </ol>)^ |
| 6397 | ** There should be exactly one call to sqlite3_backup_finish() for each |
| 6398 | ** successful call to sqlite3_backup_init(). |
| 6399 | ** |
| 6400 | ** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b> |
| 6401 | ** |
| 6402 | ** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the |
| 6403 | ** [database connection] associated with the destination database |
| 6404 | ** and the database name, respectively. |
| 6405 | ** ^The database name is "main" for the main database, "temp" for the |
| 6406 | ** temporary database, or the name specified after the AS keyword in |
| 6407 | ** an [ATTACH] statement for an attached database. |
| 6408 | ** ^The S and M arguments passed to |
| 6409 | ** sqlite3_backup_init(D,N,S,M) identify the [database connection] |
| 6410 | ** and database name of the source database, respectively. |
| 6411 | ** ^The source and destination [database connections] (parameters S and D) |
| 6412 | ** must be different or else sqlite3_backup_init(D,N,S,M) will fail with |
| 6413 | ** an error. |
| 6414 | ** |
| 6415 | ** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is |
| 6416 | ** returned and an error code and error message are stored in the |
| 6417 | ** destination [database connection] D. |
| 6418 | ** ^The error code and message for the failed call to sqlite3_backup_init() |
| 6419 | ** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or |
| 6420 | ** [sqlite3_errmsg16()] functions. |
| 6421 | ** ^A successful call to sqlite3_backup_init() returns a pointer to an |
| 6422 | ** [sqlite3_backup] object. |
| 6423 | ** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and |
| 6424 | ** sqlite3_backup_finish() functions to perform the specified backup |
| 6425 | ** operation. |
| 6426 | ** |
| 6427 | ** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b> |
| 6428 | ** |
| 6429 | ** ^Function sqlite3_backup_step(B,N) will copy up to N pages between |
| 6430 | ** the source and destination databases specified by [sqlite3_backup] object B. |
| 6431 | ** ^If N is negative, all remaining source pages are copied. |
| 6432 | ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there |
| 6433 | ** are still more pages to be copied, then the function returns [SQLITE_OK]. |
| 6434 | ** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages |
| 6435 | ** from source to destination, then it returns [SQLITE_DONE]. |
| 6436 | ** ^If an error occurs while running sqlite3_backup_step(B,N), |
| 6437 | ** then an [error code] is returned. ^As well as [SQLITE_OK] and |
| 6438 | ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY], |
| 6439 | ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an |
| 6440 | ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code. |
| 6441 | ** |
| 6442 | ** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if |
| 6443 | ** <ol> |
| 6444 | ** <li> the destination database was opened read-only, or |
| 6445 | ** <li> the destination database is using write-ahead-log journaling |
| 6446 | ** and the destination and source page sizes differ, or |
| 6447 | ** <li> the destination database is an in-memory database and the |
| 6448 | ** destination and source page sizes differ. |
| 6449 | ** </ol>)^ |
| 6450 | ** |
| 6451 | ** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then |
| 6452 | ** the [sqlite3_busy_handler | busy-handler function] |
| 6453 | ** is invoked (if one is specified). ^If the |
| 6454 | ** busy-handler returns non-zero before the lock is available, then |
| 6455 | ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to |
| 6456 | ** sqlite3_backup_step() can be retried later. ^If the source |
| 6457 | ** [database connection] |
| 6458 | ** is being used to write to the source database when sqlite3_backup_step() |
| 6459 | ** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this |
| 6460 | ** case the call to sqlite3_backup_step() can be retried later on. ^(If |
| 6461 | ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or |
| 6462 | ** [SQLITE_READONLY] is returned, then |
| 6463 | ** there is no point in retrying the call to sqlite3_backup_step(). These |
| 6464 | ** errors are considered fatal.)^ The application must accept |
| 6465 | ** that the backup operation has failed and pass the backup operation handle |
| 6466 | ** to the sqlite3_backup_finish() to release associated resources. |
| 6467 | ** |
| 6468 | ** ^The first call to sqlite3_backup_step() obtains an exclusive lock |
| 6469 | ** on the destination file. ^The exclusive lock is not released until either |
| 6470 | ** sqlite3_backup_finish() is called or the backup operation is complete |
| 6471 | ** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to |
| 6472 | ** sqlite3_backup_step() obtains a [shared lock] on the source database that |
| 6473 | ** lasts for the duration of the sqlite3_backup_step() call. |
| 6474 | ** ^Because the source database is not locked between calls to |
| 6475 | ** sqlite3_backup_step(), the source database may be modified mid-way |
| 6476 | ** through the backup process. ^If the source database is modified by an |
| 6477 | ** external process or via a database connection other than the one being |
| 6478 | ** used by the backup operation, then the backup will be automatically |
| 6479 | ** restarted by the next call to sqlite3_backup_step(). ^If the source |
| 6480 | ** database is modified by the using the same database connection as is used |
| 6481 | ** by the backup operation, then the backup database is automatically |
| 6482 | ** updated at the same time. |
| 6483 | ** |
| 6484 | ** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b> |
| 6485 | ** |
| 6486 | ** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the |
| 6487 | ** application wishes to abandon the backup operation, the application |
| 6488 | ** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish(). |
| 6489 | ** ^The sqlite3_backup_finish() interfaces releases all |
| 6490 | ** resources associated with the [sqlite3_backup] object. |
| 6491 | ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any |
| 6492 | ** active write-transaction on the destination database is rolled back. |
| 6493 | ** The [sqlite3_backup] object is invalid |
| 6494 | ** and may not be used following a call to sqlite3_backup_finish(). |
| 6495 | ** |
| 6496 | ** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no |
| 6497 | ** sqlite3_backup_step() errors occurred, regardless or whether or not |
| 6498 | ** sqlite3_backup_step() completed. |
| 6499 | ** ^If an out-of-memory condition or IO error occurred during any prior |
| 6500 | ** sqlite3_backup_step() call on the same [sqlite3_backup] object, then |
| 6501 | ** sqlite3_backup_finish() returns the corresponding [error code]. |
| 6502 | ** |
| 6503 | ** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() |
| 6504 | ** is not a permanent error and does not affect the return value of |
| 6505 | ** sqlite3_backup_finish(). |
| 6506 | ** |
| 6507 | ** [[sqlite3_backup__remaining()]] [[sqlite3_backup_pagecount()]] |
| 6508 | ** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b> |
| 6509 | ** |
| 6510 | ** ^Each call to sqlite3_backup_step() sets two values inside |
| 6511 | ** the [sqlite3_backup] object: the number of pages still to be backed |
| 6512 | ** up and the total number of pages in the source database file. |
| 6513 | ** The sqlite3_backup_remaining() and sqlite3_backup_pagecount() interfaces |
| 6514 | ** retrieve these two values, respectively. |
| 6515 | ** |
| 6516 | ** ^The values returned by these functions are only updated by |
| 6517 | ** sqlite3_backup_step(). ^If the source database is modified during a backup |
| 6518 | ** operation, then the values are not updated to account for any extra |
| 6519 | ** pages that need to be updated or the size of the source database file |
| 6520 | ** changing. |
| 6521 | ** |
| 6522 | ** <b>Concurrent Usage of Database Handles</b> |
| 6523 | ** |
| 6524 | ** ^The source [database connection] may be used by the application for other |
| 6525 | ** purposes while a backup operation is underway or being initialized. |
| 6526 | ** ^If SQLite is compiled and configured to support threadsafe database |
| 6527 | ** connections, then the source database connection may be used concurrently |
| 6528 | ** from within other threads. |
| 6529 | ** |
| 6530 | ** However, the application must guarantee that the destination |
| 6531 | ** [database connection] is not passed to any other API (by any thread) after |
| 6532 | ** sqlite3_backup_init() is called and before the corresponding call to |
| 6533 | ** sqlite3_backup_finish(). SQLite does not currently check to see |
| 6534 | ** if the application incorrectly accesses the destination [database connection] |
| 6535 | ** and so no error code is reported, but the operations may malfunction |
| 6536 | ** nevertheless. Use of the destination database connection while a |
| 6537 | ** backup is in progress might also also cause a mutex deadlock. |
| 6538 | ** |
| 6539 | ** If running in [shared cache mode], the application must |
| 6540 | ** guarantee that the shared cache used by the destination database |
| 6541 | ** is not accessed while the backup is running. In practice this means |
| 6542 | ** that the application must guarantee that the disk file being |
| 6543 | ** backed up to is not accessed by any connection within the process, |
| 6544 | ** not just the specific connection that was passed to sqlite3_backup_init(). |
| 6545 | ** |
| 6546 | ** The [sqlite3_backup] object itself is partially threadsafe. Multiple |
| 6547 | ** threads may safely make multiple concurrent calls to sqlite3_backup_step(). |
| 6548 | ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount() |
| 6549 | ** APIs are not strictly speaking threadsafe. If they are invoked at the |
| 6550 | ** same time as another thread is invoking sqlite3_backup_step() it is |
| 6551 | ** possible that they return invalid values. |
| 6552 | */ |
| 6553 | SQLITE_API sqlite3_backup *sqlite3_backup_init( |
| 6554 | sqlite3 *pDest, /* Destination database handle */ |
| 6555 | const char *zDestName, /* Destination database name */ |
| 6556 | sqlite3 *pSource, /* Source database handle */ |
| 6557 | const char *zSourceName /* Source database name */ |
| 6558 | ); |
| 6559 | SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage); |
| 6560 | SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p); |
| 6561 | SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p); |
| 6562 | SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p); |
| 6563 | |
| 6564 | /* |
| 6565 | ** CAPI3REF: Unlock Notification |
| 6566 | ** |
| 6567 | ** ^When running in shared-cache mode, a database operation may fail with |
| 6568 | ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or |
| 6569 | ** individual tables within the shared-cache cannot be obtained. See |
| 6570 | ** [SQLite Shared-Cache Mode] for a description of shared-cache locking. |
| 6571 | ** ^This API may be used to register a callback that SQLite will invoke |
| 6572 | ** when the connection currently holding the required lock relinquishes it. |
| 6573 | ** ^This API is only available if the library was compiled with the |
| 6574 | ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined. |
| 6575 | ** |
| 6576 | ** See Also: [Using the SQLite Unlock Notification Feature]. |
| 6577 | ** |
| 6578 | ** ^Shared-cache locks are released when a database connection concludes |
| 6579 | ** its current transaction, either by committing it or rolling it back. |
| 6580 | ** |
| 6581 | ** ^When a connection (known as the blocked connection) fails to obtain a |
| 6582 | ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the |
| 6583 | ** identity of the database connection (the blocking connection) that |
| 6584 | ** has locked the required resource is stored internally. ^After an |
| 6585 | ** application receives an SQLITE_LOCKED error, it may call the |
| 6586 | ** sqlite3_unlock_notify() method with the blocked connection handle as |
| 6587 | ** the first argument to register for a callback that will be invoked |
| 6588 | ** when the blocking connections current transaction is concluded. ^The |
| 6589 | ** callback is invoked from within the [sqlite3_step] or [sqlite3_close] |
| 6590 | ** call that concludes the blocking connections transaction. |
| 6591 | ** |
| 6592 | ** ^(If sqlite3_unlock_notify() is called in a multi-threaded application, |
| 6593 | ** there is a chance that the blocking connection will have already |
| 6594 | ** concluded its transaction by the time sqlite3_unlock_notify() is invoked. |
| 6595 | ** If this happens, then the specified callback is invoked immediately, |
| 6596 | ** from within the call to sqlite3_unlock_notify().)^ |
| 6597 | ** |
| 6598 | ** ^If the blocked connection is attempting to obtain a write-lock on a |
| 6599 | ** shared-cache table, and more than one other connection currently holds |
| 6600 | ** a read-lock on the same table, then SQLite arbitrarily selects one of |
| 6601 | ** the other connections to use as the blocking connection. |
| 6602 | ** |
| 6603 | ** ^(There may be at most one unlock-notify callback registered by a |
| 6604 | ** blocked connection. If sqlite3_unlock_notify() is called when the |
| 6605 | ** blocked connection already has a registered unlock-notify callback, |
| 6606 | ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is |
| 6607 | ** called with a NULL pointer as its second argument, then any existing |
| 6608 | ** unlock-notify callback is canceled. ^The blocked connections |
| 6609 | ** unlock-notify callback may also be canceled by closing the blocked |
| 6610 | ** connection using [sqlite3_close()]. |
| 6611 | ** |
| 6612 | ** The unlock-notify callback is not reentrant. If an application invokes |
| 6613 | ** any sqlite3_xxx API functions from within an unlock-notify callback, a |
| 6614 | ** crash or deadlock may be the result. |
| 6615 | ** |
| 6616 | ** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always |
| 6617 | ** returns SQLITE_OK. |
| 6618 | ** |
| 6619 | ** <b>Callback Invocation Details</b> |
| 6620 | ** |
| 6621 | ** When an unlock-notify callback is registered, the application provides a |
| 6622 | ** single void* pointer that is passed to the callback when it is invoked. |
| 6623 | ** However, the signature of the callback function allows SQLite to pass |
| 6624 | ** it an array of void* context pointers. The first argument passed to |
| 6625 | ** an unlock-notify callback is a pointer to an array of void* pointers, |
| 6626 | ** and the second is the number of entries in the array. |
| 6627 | ** |
| 6628 | ** When a blocking connections transaction is concluded, there may be |
| 6629 | ** more than one blocked connection that has registered for an unlock-notify |
| 6630 | ** callback. ^If two or more such blocked connections have specified the |
| 6631 | ** same callback function, then instead of invoking the callback function |
| 6632 | ** multiple times, it is invoked once with the set of void* context pointers |
| 6633 | ** specified by the blocked connections bundled together into an array. |
| 6634 | ** This gives the application an opportunity to prioritize any actions |
| 6635 | ** related to the set of unblocked database connections. |
| 6636 | ** |
| 6637 | ** <b>Deadlock Detection</b> |
| 6638 | ** |
| 6639 | ** Assuming that after registering for an unlock-notify callback a |
| 6640 | ** database waits for the callback to be issued before taking any further |
| 6641 | ** action (a reasonable assumption), then using this API may cause the |
| 6642 | ** application to deadlock. For example, if connection X is waiting for |
| 6643 | ** connection Y's transaction to be concluded, and similarly connection |
| 6644 | ** Y is waiting on connection X's transaction, then neither connection |
| 6645 | ** will proceed and the system may remain deadlocked indefinitely. |
| 6646 | ** |
| 6647 | ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock |
| 6648 | ** detection. ^If a given call to sqlite3_unlock_notify() would put the |
| 6649 | ** system in a deadlocked state, then SQLITE_LOCKED is returned and no |
| 6650 | ** unlock-notify callback is registered. The system is said to be in |
| 6651 | ** a deadlocked state if connection A has registered for an unlock-notify |
| 6652 | ** callback on the conclusion of connection B's transaction, and connection |
| 6653 | ** B has itself registered for an unlock-notify callback when connection |
| 6654 | ** A's transaction is concluded. ^Indirect deadlock is also detected, so |
| 6655 | ** the system is also considered to be deadlocked if connection B has |
| 6656 | ** registered for an unlock-notify callback on the conclusion of connection |
| 6657 | ** C's transaction, where connection C is waiting on connection A. ^Any |
| 6658 | ** number of levels of indirection are allowed. |
| 6659 | ** |
| 6660 | ** <b>The "DROP TABLE" Exception</b> |
| 6661 | ** |
| 6662 | ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost |
| 6663 | ** always appropriate to call sqlite3_unlock_notify(). There is however, |
| 6664 | ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement, |
| 6665 | ** SQLite checks if there are any currently executing SELECT statements |
| 6666 | ** that belong to the same connection. If there are, SQLITE_LOCKED is |
| 6667 | ** returned. In this case there is no "blocking connection", so invoking |
| 6668 | ** sqlite3_unlock_notify() results in the unlock-notify callback being |
| 6669 | ** invoked immediately. If the application then re-attempts the "DROP TABLE" |
| 6670 | ** or "DROP INDEX" query, an infinite loop might be the result. |
| 6671 | ** |
| 6672 | ** One way around this problem is to check the extended error code returned |
| 6673 | ** by an sqlite3_step() call. ^(If there is a blocking connection, then the |
| 6674 | ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in |
| 6675 | ** the special "DROP TABLE/INDEX" case, the extended error code is just |
| 6676 | ** SQLITE_LOCKED.)^ |
| 6677 | */ |
| 6678 | SQLITE_API int sqlite3_unlock_notify( |
| 6679 | sqlite3 *pBlocked, /* Waiting connection */ |
| 6680 | void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */ |
| 6681 | void *pNotifyArg /* Argument to pass to xNotify */ |
| 6682 | ); |
| 6683 | |
| 6684 | |
| 6685 | /* |
| 6686 | ** CAPI3REF: String Comparison |
| 6687 | ** |
| 6688 | ** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications |
| 6689 | ** and extensions to compare the contents of two buffers containing UTF-8 |
| 6690 | ** strings in a case-independent fashion, using the same definition of "case |
| 6691 | ** independence" that SQLite uses internally when comparing identifiers. |
| 6692 | */ |
| 6693 | SQLITE_API int sqlite3_stricmp(const char *, const char *); |
| 6694 | SQLITE_API int sqlite3_strnicmp(const char *, const char *, int); |
| 6695 | |
| 6696 | /* |
| 6697 | ** CAPI3REF: Error Logging Interface |
| 6698 | ** |
| 6699 | ** ^The [sqlite3_log()] interface writes a message into the error log |
| 6700 | ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()]. |
| 6701 | ** ^If logging is enabled, the zFormat string and subsequent arguments are |
| 6702 | ** used with [sqlite3_snprintf()] to generate the final output string. |
| 6703 | ** |
| 6704 | ** The sqlite3_log() interface is intended for use by extensions such as |
| 6705 | ** virtual tables, collating functions, and SQL functions. While there is |
| 6706 | ** nothing to prevent an application from calling sqlite3_log(), doing so |
| 6707 | ** is considered bad form. |
| 6708 | ** |
| 6709 | ** The zFormat string must not be NULL. |
| 6710 | ** |
| 6711 | ** To avoid deadlocks and other threading problems, the sqlite3_log() routine |
| 6712 | ** will not use dynamically allocated memory. The log message is stored in |
| 6713 | ** a fixed-length buffer on the stack. If the log message is longer than |
| 6714 | ** a few hundred characters, it will be truncated to the length of the |
| 6715 | ** buffer. |
| 6716 | */ |
| 6717 | SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...); |
| 6718 | |
| 6719 | /* |
| 6720 | ** CAPI3REF: Write-Ahead Log Commit Hook |
| 6721 | ** |
| 6722 | ** ^The [sqlite3_wal_hook()] function is used to register a callback that |
| 6723 | ** will be invoked each time a database connection commits data to a |
| 6724 | ** [write-ahead log] (i.e. whenever a transaction is committed in |
| 6725 | ** [journal_mode | journal_mode=WAL mode]). |
| 6726 | ** |
| 6727 | ** ^The callback is invoked by SQLite after the commit has taken place and |
| 6728 | ** the associated write-lock on the database released, so the implementation |
| 6729 | ** may read, write or [checkpoint] the database as required. |
| 6730 | ** |
| 6731 | ** ^The first parameter passed to the callback function when it is invoked |
| 6732 | ** is a copy of the third parameter passed to sqlite3_wal_hook() when |
| 6733 | ** registering the callback. ^The second is a copy of the database handle. |
| 6734 | ** ^The third parameter is the name of the database that was written to - |
| 6735 | ** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter |
| 6736 | ** is the number of pages currently in the write-ahead log file, |
| 6737 | ** including those that were just committed. |
| 6738 | ** |
| 6739 | ** The callback function should normally return [SQLITE_OK]. ^If an error |
| 6740 | ** code is returned, that error will propagate back up through the |
| 6741 | ** SQLite code base to cause the statement that provoked the callback |
| 6742 | ** to report an error, though the commit will have still occurred. If the |
| 6743 | ** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value |
| 6744 | ** that does not correspond to any valid SQLite error code, the results |
| 6745 | ** are undefined. |
| 6746 | ** |
| 6747 | ** A single database handle may have at most a single write-ahead log callback |
| 6748 | ** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any |
| 6749 | ** previously registered write-ahead log callback. ^Note that the |
| 6750 | ** [sqlite3_wal_autocheckpoint()] interface and the |
| 6751 | ** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will |
| 6752 | ** those overwrite any prior [sqlite3_wal_hook()] settings. |
| 6753 | */ |
| 6754 | SQLITE_API void *sqlite3_wal_hook( |
| 6755 | sqlite3*, |
| 6756 | int(*)(void *,sqlite3*,const char*,int), |
| 6757 | void* |
| 6758 | ); |
| 6759 | |
| 6760 | /* |
| 6761 | ** CAPI3REF: Configure an auto-checkpoint |
| 6762 | ** |
| 6763 | ** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around |
| 6764 | ** [sqlite3_wal_hook()] that causes any database on [database connection] D |
| 6765 | ** to automatically [checkpoint] |
| 6766 | ** after committing a transaction if there are N or |
| 6767 | ** more frames in the [write-ahead log] file. ^Passing zero or |
| 6768 | ** a negative value as the nFrame parameter disables automatic |
| 6769 | ** checkpoints entirely. |
| 6770 | ** |
| 6771 | ** ^The callback registered by this function replaces any existing callback |
| 6772 | ** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback |
| 6773 | ** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism |
| 6774 | ** configured by this function. |
| 6775 | ** |
| 6776 | ** ^The [wal_autocheckpoint pragma] can be used to invoke this interface |
| 6777 | ** from SQL. |
| 6778 | ** |
| 6779 | ** ^Every new [database connection] defaults to having the auto-checkpoint |
| 6780 | ** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT] |
| 6781 | ** pages. The use of this interface |
| 6782 | ** is only necessary if the default setting is found to be suboptimal |
| 6783 | ** for a particular application. |
| 6784 | */ |
| 6785 | SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N); |
| 6786 | |
| 6787 | /* |
| 6788 | ** CAPI3REF: Checkpoint a database |
| 6789 | ** |
| 6790 | ** ^The [sqlite3_wal_checkpoint(D,X)] interface causes database named X |
| 6791 | ** on [database connection] D to be [checkpointed]. ^If X is NULL or an |
| 6792 | ** empty string, then a checkpoint is run on all databases of |
| 6793 | ** connection D. ^If the database connection D is not in |
| 6794 | ** [WAL | write-ahead log mode] then this interface is a harmless no-op. |
| 6795 | ** |
| 6796 | ** ^The [wal_checkpoint pragma] can be used to invoke this interface |
| 6797 | ** from SQL. ^The [sqlite3_wal_autocheckpoint()] interface and the |
| 6798 | ** [wal_autocheckpoint pragma] can be used to cause this interface to be |
| 6799 | ** run whenever the WAL reaches a certain size threshold. |
| 6800 | ** |
| 6801 | ** See also: [sqlite3_wal_checkpoint_v2()] |
| 6802 | */ |
| 6803 | SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb); |
| 6804 | |
| 6805 | /* |
| 6806 | ** CAPI3REF: Checkpoint a database |
| 6807 | ** |
| 6808 | ** Run a checkpoint operation on WAL database zDb attached to database |
| 6809 | ** handle db. The specific operation is determined by the value of the |
| 6810 | ** eMode parameter: |
| 6811 | ** |
| 6812 | ** <dl> |
| 6813 | ** <dt>SQLITE_CHECKPOINT_PASSIVE<dd> |
| 6814 | ** Checkpoint as many frames as possible without waiting for any database |
| 6815 | ** readers or writers to finish. Sync the db file if all frames in the log |
| 6816 | ** are checkpointed. This mode is the same as calling |
| 6817 | ** sqlite3_wal_checkpoint(). The busy-handler callback is never invoked. |
| 6818 | ** |
| 6819 | ** <dt>SQLITE_CHECKPOINT_FULL<dd> |
| 6820 | ** This mode blocks (calls the busy-handler callback) until there is no |
| 6821 | ** database writer and all readers are reading from the most recent database |
| 6822 | ** snapshot. It then checkpoints all frames in the log file and syncs the |
| 6823 | ** database file. This call blocks database writers while it is running, |
| 6824 | ** but not database readers. |
| 6825 | ** |
| 6826 | ** <dt>SQLITE_CHECKPOINT_RESTART<dd> |
| 6827 | ** This mode works the same way as SQLITE_CHECKPOINT_FULL, except after |
| 6828 | ** checkpointing the log file it blocks (calls the busy-handler callback) |
| 6829 | ** until all readers are reading from the database file only. This ensures |
| 6830 | ** that the next client to write to the database file restarts the log file |
| 6831 | ** from the beginning. This call blocks database writers while it is running, |
| 6832 | ** but not database readers. |
| 6833 | ** </dl> |
| 6834 | ** |
| 6835 | ** If pnLog is not NULL, then *pnLog is set to the total number of frames in |
| 6836 | ** the log file before returning. If pnCkpt is not NULL, then *pnCkpt is set to |
| 6837 | ** the total number of checkpointed frames (including any that were already |
| 6838 | ** checkpointed when this function is called). *pnLog and *pnCkpt may be |
| 6839 | ** populated even if sqlite3_wal_checkpoint_v2() returns other than SQLITE_OK. |
| 6840 | ** If no values are available because of an error, they are both set to -1 |
| 6841 | ** before returning to communicate this to the caller. |
| 6842 | ** |
| 6843 | ** All calls obtain an exclusive "checkpoint" lock on the database file. If |
| 6844 | ** any other process is running a checkpoint operation at the same time, the |
| 6845 | ** lock cannot be obtained and SQLITE_BUSY is returned. Even if there is a |
| 6846 | ** busy-handler configured, it will not be invoked in this case. |
| 6847 | ** |
| 6848 | ** The SQLITE_CHECKPOINT_FULL and RESTART modes also obtain the exclusive |
| 6849 | ** "writer" lock on the database file. If the writer lock cannot be obtained |
| 6850 | ** immediately, and a busy-handler is configured, it is invoked and the writer |
| 6851 | ** lock retried until either the busy-handler returns 0 or the lock is |
| 6852 | ** successfully obtained. The busy-handler is also invoked while waiting for |
| 6853 | ** database readers as described above. If the busy-handler returns 0 before |
| 6854 | ** the writer lock is obtained or while waiting for database readers, the |
| 6855 | ** checkpoint operation proceeds from that point in the same way as |
| 6856 | ** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible |
| 6857 | ** without blocking any further. SQLITE_BUSY is returned in this case. |
| 6858 | ** |
| 6859 | ** If parameter zDb is NULL or points to a zero length string, then the |
| 6860 | ** specified operation is attempted on all WAL databases. In this case the |
| 6861 | ** values written to output parameters *pnLog and *pnCkpt are undefined. If |
| 6862 | ** an SQLITE_BUSY error is encountered when processing one or more of the |
| 6863 | ** attached WAL databases, the operation is still attempted on any remaining |
| 6864 | ** attached databases and SQLITE_BUSY is returned to the caller. If any other |
| 6865 | ** error occurs while processing an attached database, processing is abandoned |
| 6866 | ** and the error code returned to the caller immediately. If no error |
| 6867 | ** (SQLITE_BUSY or otherwise) is encountered while processing the attached |
| 6868 | ** databases, SQLITE_OK is returned. |
| 6869 | ** |
| 6870 | ** If database zDb is the name of an attached database that is not in WAL |
| 6871 | ** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. If |
| 6872 | ** zDb is not NULL (or a zero length string) and is not the name of any |
| 6873 | ** attached database, SQLITE_ERROR is returned to the caller. |
| 6874 | */ |
| 6875 | SQLITE_API int sqlite3_wal_checkpoint_v2( |
| 6876 | sqlite3 *db, /* Database handle */ |
| 6877 | const char *zDb, /* Name of attached database (or NULL) */ |
| 6878 | int eMode, /* SQLITE_CHECKPOINT_* value */ |
| 6879 | int *pnLog, /* OUT: Size of WAL log in frames */ |
| 6880 | int *pnCkpt /* OUT: Total number of frames checkpointed */ |
| 6881 | ); |
| 6882 | |
| 6883 | /* |
| 6884 | ** CAPI3REF: Checkpoint operation parameters |
| 6885 | ** |
| 6886 | ** These constants can be used as the 3rd parameter to |
| 6887 | ** [sqlite3_wal_checkpoint_v2()]. See the [sqlite3_wal_checkpoint_v2()] |
| 6888 | ** documentation for additional information about the meaning and use of |
| 6889 | ** each of these values. |
| 6890 | */ |
| 6891 | #define SQLITE_CHECKPOINT_PASSIVE 0 |
| 6892 | #define SQLITE_CHECKPOINT_FULL 1 |
| 6893 | #define SQLITE_CHECKPOINT_RESTART 2 |
| 6894 | |
| 6895 | /* |
| 6896 | ** CAPI3REF: Virtual Table Interface Configuration |
| 6897 | ** |
| 6898 | ** This function may be called by either the [xConnect] or [xCreate] method |
| 6899 | ** of a [virtual table] implementation to configure |
| 6900 | ** various facets of the virtual table interface. |
| 6901 | ** |
| 6902 | ** If this interface is invoked outside the context of an xConnect or |
| 6903 | ** xCreate virtual table method then the behavior is undefined. |
| 6904 | ** |
| 6905 | ** At present, there is only one option that may be configured using |
| 6906 | ** this function. (See [SQLITE_VTAB_CONSTRAINT_SUPPORT].) Further options |
| 6907 | ** may be added in the future. |
| 6908 | */ |
| 6909 | SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...); |
| 6910 | |
| 6911 | /* |
| 6912 | ** CAPI3REF: Virtual Table Configuration Options |
| 6913 | ** |
| 6914 | ** These macros define the various options to the |
| 6915 | ** [sqlite3_vtab_config()] interface that [virtual table] implementations |
| 6916 | ** can use to customize and optimize their behavior. |
| 6917 | ** |
| 6918 | ** <dl> |
| 6919 | ** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT |
| 6920 | ** <dd>Calls of the form |
| 6921 | ** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported, |
| 6922 | ** where X is an integer. If X is zero, then the [virtual table] whose |
| 6923 | ** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not |
| 6924 | ** support constraints. In this configuration (which is the default) if |
| 6925 | ** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire |
| 6926 | ** statement is rolled back as if [ON CONFLICT | OR ABORT] had been |
| 6927 | ** specified as part of the users SQL statement, regardless of the actual |
| 6928 | ** ON CONFLICT mode specified. |
| 6929 | ** |
| 6930 | ** If X is non-zero, then the virtual table implementation guarantees |
| 6931 | ** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before |
| 6932 | ** any modifications to internal or persistent data structures have been made. |
| 6933 | ** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite |
| 6934 | ** is able to roll back a statement or database transaction, and abandon |
| 6935 | ** or continue processing the current SQL statement as appropriate. |
| 6936 | ** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns |
| 6937 | ** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode |
| 6938 | ** had been ABORT. |
| 6939 | ** |
| 6940 | ** Virtual table implementations that are required to handle OR REPLACE |
| 6941 | ** must do so within the [xUpdate] method. If a call to the |
| 6942 | ** [sqlite3_vtab_on_conflict()] function indicates that the current ON |
| 6943 | ** CONFLICT policy is REPLACE, the virtual table implementation should |
| 6944 | ** silently replace the appropriate rows within the xUpdate callback and |
| 6945 | ** return SQLITE_OK. Or, if this is not possible, it may return |
| 6946 | ** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT |
| 6947 | ** constraint handling. |
| 6948 | ** </dl> |
| 6949 | */ |
| 6950 | #define SQLITE_VTAB_CONSTRAINT_SUPPORT 1 |
| 6951 | |
| 6952 | /* |
| 6953 | ** CAPI3REF: Determine The Virtual Table Conflict Policy |
| 6954 | ** |
| 6955 | ** This function may only be called from within a call to the [xUpdate] method |
| 6956 | ** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The |
| 6957 | ** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL], |
| 6958 | ** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode |
| 6959 | ** of the SQL statement that triggered the call to the [xUpdate] method of the |
| 6960 | ** [virtual table]. |
| 6961 | */ |
| 6962 | SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *); |
| 6963 | |
| 6964 | /* |
| 6965 | ** CAPI3REF: Conflict resolution modes |
| 6966 | ** |
| 6967 | ** These constants are returned by [sqlite3_vtab_on_conflict()] to |
| 6968 | ** inform a [virtual table] implementation what the [ON CONFLICT] mode |
| 6969 | ** is for the SQL statement being evaluated. |
| 6970 | ** |
| 6971 | ** Note that the [SQLITE_IGNORE] constant is also used as a potential |
| 6972 | ** return value from the [sqlite3_set_authorizer()] callback and that |
| 6973 | ** [SQLITE_ABORT] is also a [result code]. |
| 6974 | */ |
| 6975 | #define SQLITE_ROLLBACK 1 |
| 6976 | /* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */ |
| 6977 | #define SQLITE_FAIL 3 |
| 6978 | /* #define SQLITE_ABORT 4 // Also an error code */ |
| 6979 | #define SQLITE_REPLACE 5 |
| 6980 | |
| 6981 | |
| 6982 | |
| 6983 | /* |
| 6984 | ** Undo the hack that converts floating point types to integer for |
| 6985 | ** builds on processors without floating point support. |
| 6986 | */ |
| 6987 | #ifdef SQLITE_OMIT_FLOATING_POINT |
| 6988 | # undef double |
| 6989 | #endif |
| 6990 | |
| 6991 | #ifdef __cplusplus |
| 6992 | } /* End of the 'extern "C"' block */ |
| 6993 | #endif |
| 6994 | #endif |
| 6995 | |
| 6996 | /* |
| 6997 | ** 2010 August 30 |
| 6998 | ** |
| 6999 | ** The author disclaims copyright to this source code. In place of |
| 7000 | ** a legal notice, here is a blessing: |
| 7001 | ** |
| 7002 | ** May you do good and not evil. |
| 7003 | ** May you find forgiveness for yourself and forgive others. |
| 7004 | ** May you share freely, never taking more than you give. |
| 7005 | ** |
| 7006 | ************************************************************************* |
| 7007 | */ |
| 7008 | |
| 7009 | #ifndef _SQLITE3RTREE_H_ |
| 7010 | #define _SQLITE3RTREE_H_ |
| 7011 | |
| 7012 | |
| 7013 | #ifdef __cplusplus |
| 7014 | extern "C" { |
| 7015 | #endif |
| 7016 | |
| 7017 | typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry; |
| 7018 | |
| 7019 | /* |
| 7020 | ** Register a geometry callback named zGeom that can be used as part of an |
| 7021 | ** R-Tree geometry query as follows: |
| 7022 | ** |
| 7023 | ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...) |
| 7024 | */ |
| 7025 | SQLITE_API int sqlite3_rtree_geometry_callback( |
| 7026 | sqlite3 *db, |
| 7027 | const char *zGeom, |
| 7028 | #ifdef SQLITE_RTREE_INT_ONLY |
| 7029 | int (*xGeom)(sqlite3_rtree_geometry*, int n, sqlite3_int64 *a, int *pRes), |
| 7030 | #else |
| 7031 | int (*xGeom)(sqlite3_rtree_geometry*, int n, double *a, int *pRes), |
| 7032 | #endif |
| 7033 | void *pContext |
| 7034 | ); |
| 7035 | |
| 7036 | |
| 7037 | /* |
| 7038 | ** A pointer to a structure of the following type is passed as the first |
| 7039 | ** argument to callbacks registered using rtree_geometry_callback(). |
| 7040 | */ |
| 7041 | struct sqlite3_rtree_geometry { |
| 7042 | void *pContext; /* Copy of pContext passed to s_r_g_c() */ |
| 7043 | int nParam; /* Size of array aParam[] */ |
| 7044 | double *aParam; /* Parameters passed to SQL geom function */ |
| 7045 | void *pUser; /* Callback implementation user data */ |
| 7046 | void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */ |
| 7047 | }; |
| 7048 | |
| 7049 | |
| 7050 | #ifdef __cplusplus |
| 7051 | } /* end of the 'extern "C"' block */ |
| 7052 | #endif |
| 7053 | |
| 7054 | #endif /* ifndef _SQLITE3RTREE_H_ */ |
| 7055 | |