Annotation of win32/sql/sqlite/include/sqlite3.h, revision 1.3
1.1 misha 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
1.2 misha 13: ** presents to client programs. If a C-function, structure, datatype,
14: ** or constant definition does not appear in this file, then it is
15: ** not a published API of SQLite, is subject to change without
16: ** notice, and should not be referenced by programs that use SQLite.
17: **
18: ** Some of the definitions that are in this file are marked as
19: ** "experimental". Experimental interfaces are normally new
20: ** features recently added to SQLite. We do not anticipate changes
21: ** to experimental interfaces but reserve to make minor changes if
22: ** experience from use "in the wild" suggest such changes are prudent.
23: **
24: ** The official C-language API documentation for SQLite is derived
25: ** from comments in this file. This file is the authoritative source
26: ** on how SQLite interfaces are suppose to operate.
27: **
28: ** The name of this file under configuration management is "sqlite.h.in".
29: ** The makefile makes some minor changes to this file (such as inserting
30: ** the version number) and changes its name to "sqlite3.h" as
31: ** part of the build process.
1.1 misha 32: **
1.3 ! misha 33: ** @(#) $Id: sqlite.h.in,v 1.269 2007/11/05 17:54:17 drh Exp $
1.1 misha 34: */
35: #ifndef _SQLITE3_H_
36: #define _SQLITE3_H_
37: #include <stdarg.h> /* Needed for the definition of va_list */
38:
39: /*
40: ** Make sure we can call this stuff from C++.
41: */
42: #ifdef __cplusplus
43: extern "C" {
44: #endif
45:
1.2 misha 46:
47: /*
48: ** Add the ability to override 'extern'
49: */
50: #ifndef SQLITE_EXTERN
51: # define SQLITE_EXTERN extern
52: #endif
53:
1.1 misha 54: /*
1.2 misha 55: ** Make sure these symbols where not defined by some previous header
56: ** file.
1.1 misha 57: */
58: #ifdef SQLITE_VERSION
59: # undef SQLITE_VERSION
1.2 misha 60: #endif
61: #ifdef SQLITE_VERSION_NUMBER
62: # undef SQLITE_VERSION_NUMBER
1.1 misha 63: #endif
64:
65: /*
1.2 misha 66: ** CAPI3REF: Compile-Time Library Version Numbers
67: **
68: ** The version of the SQLite library is contained in the sqlite3.h
69: ** header file in a #define named SQLITE_VERSION. The SQLITE_VERSION
70: ** macro resolves to a string constant.
71: **
72: ** The format of the version string is "X.Y.Z", where
73: ** X is the major version number, Y is the minor version number and Z
74: ** is the release number. The X.Y.Z might be followed by "alpha" or "beta".
75: ** For example "3.1.1beta".
76: **
77: ** The X value is always 3 in SQLite. The X value only changes when
78: ** backwards compatibility is broken and we intend to never break
79: ** backwards compatibility. The Y value only changes when
80: ** there are major feature enhancements that are forwards compatible
81: ** but not backwards compatible. The Z value is incremented with
82: ** each release but resets back to 0 when Y is incremented.
83: **
84: ** The SQLITE_VERSION_NUMBER is an integer with the value
85: ** (X*1000000 + Y*1000 + Z). For example, for version "3.1.1beta",
86: ** SQLITE_VERSION_NUMBER is set to 3001001. To detect if they are using
87: ** version 3.1.1 or greater at compile time, programs may use the test
88: ** (SQLITE_VERSION_NUMBER>=3001001).
89: **
90: ** See also: [sqlite3_libversion()] and [sqlite3_libversion_number()].
91: */
1.3 ! misha 92: #define SQLITE_VERSION "3.5.2"
! 93: #define SQLITE_VERSION_NUMBER 3005002
1.2 misha 94:
95: /*
96: ** CAPI3REF: Run-Time Library Version Numbers
97: **
98: ** These routines return values equivalent to the header constants
99: ** [SQLITE_VERSION] and [SQLITE_VERSION_NUMBER]. The values returned
100: ** by this routines should only be different from the header values
101: ** if you compile your program using an sqlite3.h header from a
102: ** different version of SQLite that the version of the library you
103: ** link against.
104: **
105: ** The sqlite3_version[] string constant contains the text of the
106: ** [SQLITE_VERSION] string. The sqlite3_libversion() function returns
107: ** a poiner to the sqlite3_version[] string constant. The function
108: ** is provided for DLL users who can only access functions and not
109: ** constants within the DLL.
1.1 misha 110: */
1.2 misha 111: SQLITE_EXTERN const char sqlite3_version[];
1.1 misha 112: const char *sqlite3_libversion(void);
1.2 misha 113: int sqlite3_libversion_number(void);
1.1 misha 114:
115: /*
1.2 misha 116: ** CAPI3REF: Test To See If The Library Is Threadsafe
117: **
118: ** This routine returns TRUE (nonzero) if SQLite was compiled with
119: ** all of its mutexes enabled and is thus threadsafe. It returns
120: ** zero if the particular build is for single-threaded operation
121: ** only.
122: **
123: ** Really all this routine does is return true if SQLite was compiled
124: ** with the -DSQLITE_THREADSAFE=1 option and false if
125: ** compiled with -DSQLITE_THREADSAFE=0. If SQLite uses an
126: ** application-defined mutex subsystem, malloc subsystem, collating
127: ** sequence, VFS, SQL function, progress callback, commit hook,
128: ** extension, or other accessories and these add-ons are not
129: ** threadsafe, then clearly the combination will not be threadsafe
130: ** either. Hence, this routine never reports that the library
131: ** is guaranteed to be threadsafe, only when it is guaranteed not
132: ** to be.
133: **
134: ** This is an experimental API and may go away or change in future
135: ** releases.
136: */
137: int sqlite3_threadsafe(void);
138:
139: /*
140: ** CAPI3REF: Database Connection Handle
141: **
142: ** Each open SQLite database is represented by pointer to an instance of the
143: ** opaque structure named "sqlite3". It is useful to think of an sqlite3
144: ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
145: ** [sqlite3_open_v2()] interfaces are its constructors
146: ** and [sqlite3_close()] is its destructor. There are many other interfaces
147: ** (such as [sqlite3_prepare_v2()], [sqlite3_create_function()], and
148: ** [sqlite3_busy_timeout()] to name but three) that are methods on this
149: ** object.
1.1 misha 150: */
151: typedef struct sqlite3 sqlite3;
152:
153:
154: /*
1.2 misha 155: ** CAPI3REF: 64-Bit Integer Types
156: **
1.1 misha 157: ** Some compilers do not support the "long long" datatype. So we have
1.2 misha 158: ** to do compiler-specific typedefs for 64-bit signed and unsigned integers.
159: **
160: ** Many SQLite interface functions require a 64-bit integer arguments.
161: ** Those interfaces are declared using this typedef.
1.1 misha 162: */
1.2 misha 163: #ifdef SQLITE_INT64_TYPE
164: typedef SQLITE_INT64_TYPE sqlite_int64;
165: typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
166: #elif defined(_MSC_VER) || defined(__BORLANDC__)
1.1 misha 167: typedef __int64 sqlite_int64;
168: typedef unsigned __int64 sqlite_uint64;
169: #else
170: typedef long long int sqlite_int64;
171: typedef unsigned long long int sqlite_uint64;
172: #endif
1.2 misha 173: typedef sqlite_int64 sqlite3_int64;
174: typedef sqlite_uint64 sqlite3_uint64;
1.1 misha 175:
1.2 misha 176: /*
177: ** If compiling for a processor that lacks floating point support,
178: ** substitute integer for floating-point
179: */
180: #ifdef SQLITE_OMIT_FLOATING_POINT
181: # define double sqlite3_int64
182: #endif
1.1 misha 183:
184: /*
1.2 misha 185: ** CAPI3REF: Closing A Database Connection
1.1 misha 186: **
187: ** Call this function with a pointer to a structure that was previously
1.2 misha 188: ** returned from [sqlite3_open()], [sqlite3_open16()], or
189: ** [sqlite3_open_v2()] and the corresponding database will by
190: ** closed.
191: **
192: ** All SQL statements prepared using [sqlite3_prepare_v2()] or
193: ** [sqlite3_prepare16_v2()] must be destroyed using [sqlite3_finalize()]
194: ** before this routine is called. Otherwise, SQLITE_BUSY is returned and the
195: ** database connection remains open.
1.1 misha 196: **
1.2 misha 197: ** Passing this routine a database connection that has already been
198: ** closed results in undefined behavior. If other interfaces that
199: ** reference the same database connection are pending (either in the
200: ** same thread or in different threads) when this routine is called,
201: ** then the behavior is undefined and is almost certainly undesirable.
1.1 misha 202: */
203: int sqlite3_close(sqlite3 *);
204:
205: /*
206: ** The type for a callback function.
1.2 misha 207: ** This is legacy and deprecated. It is included for historical
208: ** compatibility and is not documented.
1.1 misha 209: */
210: typedef int (*sqlite3_callback)(void*,int,char**, char**);
211:
212: /*
1.2 misha 213: ** CAPI3REF: One-Step Query Execution Interface
214: **
215: ** This interface is used to do a one-time evaluatation of zero
216: ** or more SQL statements. UTF-8 text of the SQL statements to
217: ** be evaluted is passed in as the second parameter. The statements
218: ** are prepared one by one using [sqlite3_prepare()], evaluated
219: ** using [sqlite3_step()], then destroyed using [sqlite3_finalize()].
1.1 misha 220: **
221: ** If one or more of the SQL statements are queries, then
222: ** the callback function specified by the 3rd parameter is
223: ** invoked once for each row of the query result. This callback
224: ** should normally return 0. If the callback returns a non-zero
225: ** value then the query is aborted, all subsequent SQL statements
1.2 misha 226: ** are skipped and the sqlite3_exec() function returns the [SQLITE_ABORT].
1.1 misha 227: **
1.2 misha 228: ** The 4th parameter to this interface is an arbitrary pointer that is
229: ** passed through to the callback function as its first parameter.
1.1 misha 230: **
231: ** The 2nd parameter to the callback function is the number of
232: ** columns in the query result. The 3rd parameter to the callback
1.2 misha 233: ** is an array of strings holding the values for each column
234: ** as extracted using [sqlite3_column_text()].
235: ** The 4th parameter to the callback is an array of strings
236: ** obtained using [sqlite3_column_name()] and holding
1.1 misha 237: ** the names of each column.
238: **
239: ** The callback function may be NULL, even for queries. A NULL
240: ** callback is not an error. It just means that no callback
241: ** will be invoked.
242: **
243: ** If an error occurs while parsing or evaluating the SQL (but
244: ** not while executing the callback) then an appropriate error
1.2 misha 245: ** message is written into memory obtained from [sqlite3_malloc()] and
1.1 misha 246: ** *errmsg is made to point to that message. The calling function
1.2 misha 247: ** is responsible for freeing the memory using [sqlite3_free()].
248: ** If errmsg==NULL, then no error message is ever written.
1.1 misha 249: **
250: ** The return value is is SQLITE_OK if there are no errors and
1.2 misha 251: ** some other [SQLITE_OK | return code] if there is an error.
252: ** The particular return value depends on the type of error.
1.1 misha 253: **
254: */
255: int sqlite3_exec(
1.2 misha 256: sqlite3*, /* An open database */
257: const char *sql, /* SQL to be evaluted */
258: int (*callback)(void*,int,char**,char**), /* Callback function */
259: void *, /* 1st argument to callback */
260: char **errmsg /* Error msg written here */
1.1 misha 261: );
262:
263: /*
1.2 misha 264: ** CAPI3REF: Result Codes
265: ** KEYWORDS: SQLITE_OK
266: **
267: ** Many SQLite functions return an integer result code from the set shown
268: ** above in order to indicates success or failure.
269: **
270: ** The result codes above are the only ones returned by SQLite in its
271: ** default configuration. However, the [sqlite3_extended_result_codes()]
272: ** API can be used to set a database connectoin to return more detailed
273: ** result codes.
274: **
275: ** See also: [SQLITE_IOERR_READ | extended result codes]
276: **
1.1 misha 277: */
278: #define SQLITE_OK 0 /* Successful result */
1.2 misha 279: /* beginning-of-error-codes */
1.1 misha 280: #define SQLITE_ERROR 1 /* SQL error or missing database */
1.2 misha 281: #define SQLITE_INTERNAL 2 /* NOT USED. Internal logic error in SQLite */
1.1 misha 282: #define SQLITE_PERM 3 /* Access permission denied */
283: #define SQLITE_ABORT 4 /* Callback routine requested an abort */
284: #define SQLITE_BUSY 5 /* The database file is locked */
285: #define SQLITE_LOCKED 6 /* A table in the database is locked */
286: #define SQLITE_NOMEM 7 /* A malloc() failed */
287: #define SQLITE_READONLY 8 /* Attempt to write a readonly database */
288: #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
289: #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
290: #define SQLITE_CORRUPT 11 /* The database disk image is malformed */
1.2 misha 291: #define SQLITE_NOTFOUND 12 /* NOT USED. Table or record not found */
1.1 misha 292: #define SQLITE_FULL 13 /* Insertion failed because database is full */
293: #define SQLITE_CANTOPEN 14 /* Unable to open the database file */
1.2 misha 294: #define SQLITE_PROTOCOL 15 /* NOT USED. Database lock protocol error */
1.1 misha 295: #define SQLITE_EMPTY 16 /* Database is empty */
296: #define SQLITE_SCHEMA 17 /* The database schema changed */
1.2 misha 297: #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
298: #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
1.1 misha 299: #define SQLITE_MISMATCH 20 /* Data type mismatch */
300: #define SQLITE_MISUSE 21 /* Library used incorrectly */
301: #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
302: #define SQLITE_AUTH 23 /* Authorization denied */
303: #define SQLITE_FORMAT 24 /* Auxiliary database format error */
304: #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
305: #define SQLITE_NOTADB 26 /* File opened that is not a database file */
306: #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
307: #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
1.2 misha 308: /* end-of-error-codes */
1.1 misha 309:
310: /*
1.2 misha 311: ** CAPI3REF: Extended Result Codes
1.1 misha 312: **
1.2 misha 313: ** In its default configuration, SQLite API routines return one of 26 integer
314: ** result codes described at result-codes. However, experience has shown that
315: ** many of these result codes are too course-grained. They do not provide as
316: ** much information about problems as users might like. In an effort to
317: ** address this, newer versions of SQLite (version 3.3.8 and later) include
318: ** support for additional result codes that provide more detailed information
319: ** about errors. The extended result codes are enabled (or disabled) for
320: ** each database
321: ** connection using the [sqlite3_extended_result_codes()] API.
322: **
323: ** Some of the available extended result codes are listed above.
324: ** We expect the number of extended result codes will be expand
325: ** over time. Software that uses extended result codes should expect
326: ** to see new result codes in future releases of SQLite.
327: **
328: ** The symbolic name for an extended result code always contains a related
329: ** primary result code as a prefix. Primary result codes contain a single
330: ** "_" character. Extended result codes contain two or more "_" characters.
331: ** The numeric value of an extended result code can be converted to its
332: ** corresponding primary result code by masking off the lower 8 bytes.
333: **
334: ** The SQLITE_OK result code will never be extended. It will always
335: ** be exactly zero.
336: */
337: #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
338: #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
339: #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
340: #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
341: #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
342: #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
343: #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
344: #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
345: #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
346: #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
347: #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
348: #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
349:
350: /*
351: ** CAPI3REF: Flags For File Open Operations
352: **
353: ** Combination of the following bit values are used as the
354: ** third argument to the [sqlite3_open_v2()] interface and
355: ** as fourth argument to the xOpen method of the
356: ** [sqlite3_vfs] object.
357: **
358: */
359: #define SQLITE_OPEN_READONLY 0x00000001
360: #define SQLITE_OPEN_READWRITE 0x00000002
361: #define SQLITE_OPEN_CREATE 0x00000004
362: #define SQLITE_OPEN_DELETEONCLOSE 0x00000008
363: #define SQLITE_OPEN_EXCLUSIVE 0x00000010
364: #define SQLITE_OPEN_MAIN_DB 0x00000100
365: #define SQLITE_OPEN_TEMP_DB 0x00000200
366: #define SQLITE_OPEN_TRANSIENT_DB 0x00000400
367: #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800
368: #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000
369: #define SQLITE_OPEN_SUBJOURNAL 0x00002000
370: #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000
371:
372: /*
373: ** CAPI3REF: Device Characteristics
374: **
375: ** The xDeviceCapabilities method of the [sqlite3_io_methods]
376: ** object returns an integer which is a vector of the following
377: ** bit values expressing I/O characteristics of the mass storage
378: ** device that holds the file that the [sqlite3_io_methods]
379: ** refers to.
380: **
381: ** The SQLITE_IOCAP_ATOMIC property means that all writes of
382: ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
383: ** mean that writes of blocks that are nnn bytes in size and
384: ** are aligned to an address which is an integer multiple of
385: ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
386: ** that when data is appended to a file, the data is appended
387: ** first then the size of the file is extended, never the other
388: ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
389: ** information is written to disk in the same order as calls
390: ** to xWrite().
391: */
392: #define SQLITE_IOCAP_ATOMIC 0x00000001
393: #define SQLITE_IOCAP_ATOMIC512 0x00000002
394: #define SQLITE_IOCAP_ATOMIC1K 0x00000004
395: #define SQLITE_IOCAP_ATOMIC2K 0x00000008
396: #define SQLITE_IOCAP_ATOMIC4K 0x00000010
397: #define SQLITE_IOCAP_ATOMIC8K 0x00000020
398: #define SQLITE_IOCAP_ATOMIC16K 0x00000040
399: #define SQLITE_IOCAP_ATOMIC32K 0x00000080
400: #define SQLITE_IOCAP_ATOMIC64K 0x00000100
401: #define SQLITE_IOCAP_SAFE_APPEND 0x00000200
402: #define SQLITE_IOCAP_SEQUENTIAL 0x00000400
403:
404: /*
405: ** CAPI3REF: File Locking Levels
406: **
407: ** SQLite uses one of the following integer values as the second
408: ** argument to calls it makes to the xLock() and xUnlock() methods
409: ** of an [sqlite3_io_methods] object.
410: */
411: #define SQLITE_LOCK_NONE 0
412: #define SQLITE_LOCK_SHARED 1
413: #define SQLITE_LOCK_RESERVED 2
414: #define SQLITE_LOCK_PENDING 3
415: #define SQLITE_LOCK_EXCLUSIVE 4
416:
417: /*
418: ** CAPI3REF: Synchronization Type Flags
419: **
420: ** When SQLite invokes the xSync() method of an [sqlite3_io_methods]
421: ** object it uses a combination of the following integer values as
422: ** the second argument.
423: **
424: ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
425: ** sync operation only needs to flush data to mass storage. Inode
426: ** information need not be flushed. The SQLITE_SYNC_NORMAL means
427: ** to use normal fsync() semantics. The SQLITE_SYNC_FULL flag means
428: ** to use Mac OS-X style fullsync instead of fsync().
429: */
430: #define SQLITE_SYNC_NORMAL 0x00002
431: #define SQLITE_SYNC_FULL 0x00003
432: #define SQLITE_SYNC_DATAONLY 0x00010
433:
434:
435: /*
436: ** CAPI3REF: OS Interface Open File Handle
437: **
438: ** An [sqlite3_file] object represents an open file in the OS
439: ** interface layer. Individual OS interface implementations will
440: ** want to subclass this object by appending additional fields
441: ** for their own use. The pMethods entry is a pointer to an
442: ** [sqlite3_io_methods] object that defines methods for performing
443: ** I/O operations on the open file.
444: */
445: typedef struct sqlite3_file sqlite3_file;
446: struct sqlite3_file {
447: const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
448: };
449:
450: /*
451: ** CAPI3REF: OS Interface File Virtual Methods Object
452: **
453: ** Every file opened by the [sqlite3_vfs] xOpen method contains a pointer to
454: ** an instance of the this object. This object defines the
455: ** methods used to perform various operations against the open file.
456: **
457: ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
458: ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
459: * The second choice is an
460: ** OS-X style fullsync. The SQLITE_SYNC_DATA flag may be ORed in to
461: ** indicate that only the data of the file and not its inode needs to be
462: ** synced.
463: **
464: ** The integer values to xLock() and xUnlock() are one of
465: ** <ul>
466: ** <li> [SQLITE_LOCK_NONE],
467: ** <li> [SQLITE_LOCK_SHARED],
468: ** <li> [SQLITE_LOCK_RESERVED],
469: ** <li> [SQLITE_LOCK_PENDING], or
470: ** <li> [SQLITE_LOCK_EXCLUSIVE].
471: ** </ul>
472: ** xLock() increases the lock. xUnlock() decreases the lock.
473: ** The xCheckReservedLock() method looks
474: ** to see if any database connection, either in this
475: ** process or in some other process, is holding an RESERVED,
476: ** PENDING, or EXCLUSIVE lock on the file. It returns true
477: ** if such a lock exists and false if not.
478: **
479: ** The xFileControl() method is a generic interface that allows custom
480: ** VFS implementations to directly control an open file using the
481: ** [sqlite3_file_control()] interface. The second "op" argument
482: ** is an integer opcode. The third
483: ** argument is a generic pointer which is intended to be a pointer
484: ** to a structure that may contain arguments or space in which to
485: ** write return values. Potential uses for xFileControl() might be
486: ** functions to enable blocking locks with timeouts, to change the
487: ** locking strategy (for example to use dot-file locks), to inquire
488: ** about the status of a lock, or to break stale locks. The SQLite
489: ** core reserves opcodes less than 100 for its own use.
490: ** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
491: ** Applications that define a custom xFileControl method should use opcodes
492: ** greater than 100 to avoid conflicts.
493: **
494: ** The xSectorSize() method returns the sector size of the
495: ** device that underlies the file. The sector size is the
496: ** minimum write that can be performed without disturbing
497: ** other bytes in the file. The xDeviceCharacteristics()
498: ** method returns a bit vector describing behaviors of the
499: ** underlying device:
500: **
501: ** <ul>
502: ** <li> [SQLITE_IOCAP_ATOMIC]
503: ** <li> [SQLITE_IOCAP_ATOMIC512]
504: ** <li> [SQLITE_IOCAP_ATOMIC1K]
505: ** <li> [SQLITE_IOCAP_ATOMIC2K]
506: ** <li> [SQLITE_IOCAP_ATOMIC4K]
507: ** <li> [SQLITE_IOCAP_ATOMIC8K]
508: ** <li> [SQLITE_IOCAP_ATOMIC16K]
509: ** <li> [SQLITE_IOCAP_ATOMIC32K]
510: ** <li> [SQLITE_IOCAP_ATOMIC64K]
511: ** <li> [SQLITE_IOCAP_SAFE_APPEND]
512: ** <li> [SQLITE_IOCAP_SEQUENTIAL]
513: ** </ul>
514: **
515: ** The SQLITE_IOCAP_ATOMIC property means that all writes of
516: ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
517: ** mean that writes of blocks that are nnn bytes in size and
518: ** are aligned to an address which is an integer multiple of
519: ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
520: ** that when data is appended to a file, the data is appended
521: ** first then the size of the file is extended, never the other
522: ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
523: ** information is written to disk in the same order as calls
524: ** to xWrite().
525: */
526: typedef struct sqlite3_io_methods sqlite3_io_methods;
527: struct sqlite3_io_methods {
528: int iVersion;
529: int (*xClose)(sqlite3_file*);
530: int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
531: int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
532: int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
533: int (*xSync)(sqlite3_file*, int flags);
534: int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
535: int (*xLock)(sqlite3_file*, int);
536: int (*xUnlock)(sqlite3_file*, int);
537: int (*xCheckReservedLock)(sqlite3_file*);
538: int (*xFileControl)(sqlite3_file*, int op, void *pArg);
539: int (*xSectorSize)(sqlite3_file*);
540: int (*xDeviceCharacteristics)(sqlite3_file*);
541: /* Additional methods may be added in future releases */
542: };
543:
544: /*
545: ** CAPI3REF: Standard File Control Opcodes
546: **
547: ** These integer constants are opcodes for the xFileControl method
548: ** of the [sqlite3_io_methods] object and to the [sqlite3_file_control()]
549: ** interface.
550: **
551: ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
552: ** opcode cases the xFileControl method to write the current state of
553: ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
554: ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
555: ** into an integer that the pArg argument points to. This capability
556: ** is used during testing and only needs to be supported when SQLITE_TEST
557: ** is defined.
558: */
559: #define SQLITE_FCNTL_LOCKSTATE 1
560:
561: /*
562: ** CAPI3REF: Mutex Handle
563: **
564: ** The mutex module within SQLite defines [sqlite3_mutex] to be an
565: ** abstract type for a mutex object. The SQLite core never looks
566: ** at the internal representation of an [sqlite3_mutex]. It only
567: ** deals with pointers to the [sqlite3_mutex] object.
568: **
569: ** Mutexes are created using [sqlite3_mutex_alloc()].
570: */
571: typedef struct sqlite3_mutex sqlite3_mutex;
572:
573: /*
574: ** CAPI3REF: OS Interface Object
575: **
576: ** An instance of this object defines the interface between the
577: ** SQLite core and the underlying operating system. The "vfs"
578: ** in the name of the object stands for "virtual file system".
579: **
580: ** The iVersion field is initially 1 but may be larger for future
581: ** versions of SQLite. Additional fields may be appended to this
582: ** object when the iVersion value is increased.
583: **
584: ** The szOsFile field is the size of the subclassed [sqlite3_file]
585: ** structure used by this VFS. mxPathname is the maximum length of
586: ** a pathname in this VFS.
587: **
588: ** Registered vfs modules are kept on a linked list formed by
589: ** the pNext pointer. The [sqlite3_vfs_register()]
590: ** and [sqlite3_vfs_unregister()] interfaces manage this list
591: ** in a thread-safe way. The [sqlite3_vfs_find()] interface
592: ** searches the list.
593: **
594: ** The pNext field is the only fields in the sqlite3_vfs
595: ** structure that SQLite will ever modify. SQLite will only access
596: ** or modify this field while holding a particular static mutex.
597: ** The application should never modify anything within the sqlite3_vfs
598: ** object once the object has been registered.
599: **
600: ** The zName field holds the name of the VFS module. The name must
601: ** be unique across all VFS modules.
602: **
603: ** SQLite will guarantee that the zFilename string passed to
604: ** xOpen() is a full pathname as generated by xFullPathname() and
605: ** that the string will be valid and unchanged until xClose() is
606: ** called. So the [sqlite3_file] can store a pointer to the
607: ** filename if it needs to remember the filename for some reason.
608: **
609: ** The flags argument to xOpen() is a copy of the flags argument
610: ** to [sqlite3_open_v2()]. If [sqlite3_open()] or [sqlite3_open16()]
611: ** is used, then flags is [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
612: ** If xOpen() opens a file read-only then it sets *pOutFlags to
613: ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be
614: ** set.
615: **
616: ** SQLite will also add one of the following flags to the xOpen()
617: ** call, depending on the object being opened:
618: **
619: ** <ul>
620: ** <li> [SQLITE_OPEN_MAIN_DB]
621: ** <li> [SQLITE_OPEN_MAIN_JOURNAL]
622: ** <li> [SQLITE_OPEN_TEMP_DB]
623: ** <li> [SQLITE_OPEN_TEMP_JOURNAL]
624: ** <li> [SQLITE_OPEN_TRANSIENT_DB]
625: ** <li> [SQLITE_OPEN_SUBJOURNAL]
626: ** <li> [SQLITE_OPEN_MASTER_JOURNAL]
627: ** </ul>
628: **
629: ** The file I/O implementation can use the object type flags to
630: ** changes the way it deals with files. For example, an application
631: ** that does not care about crash recovery or rollback, might make
632: ** the open of a journal file a no-op. Writes to this journal are
633: ** also a no-op. Any attempt to read the journal return SQLITE_IOERR.
634: ** Or the implementation might recognize the a database file will
635: ** be doing page-aligned sector reads and writes in a random order
636: ** and set up its I/O subsystem accordingly.
637: **
638: ** SQLite might also add one of the following flags to the xOpen
639: ** method:
640: **
641: ** <ul>
642: ** <li> [SQLITE_OPEN_DELETEONCLOSE]
643: ** <li> [SQLITE_OPEN_EXCLUSIVE]
644: ** </ul>
645: **
646: ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
647: ** deleted when it is closed. This will always be set for TEMP
648: ** databases and journals and for subjournals. The
649: ** [SQLITE_OPEN_EXCLUSIVE] flag means the file should be opened
650: ** for exclusive access. This flag is set for all files except
651: ** for the main database file.
652: **
653: ** Space to hold the [sqlite3_file] structure passed as the third
654: ** argument to xOpen is allocated by caller (the SQLite core).
655: ** szOsFile bytes are allocated for this object. The xOpen method
656: ** fills in the allocated space.
657: **
658: ** The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
659: ** to test for the existance of a file,
660: ** or [SQLITE_ACCESS_READWRITE] to test to see
661: ** if a file is readable and writable, or [SQLITE_ACCESS_READ]
662: ** to test to see if a file is at least readable. The file can be a
663: ** directory.
664: **
665: ** SQLite will always allocate at least mxPathname+1 byte for
666: ** the output buffers for xGetTempname and xFullPathname. The exact
667: ** size of the output buffer is also passed as a parameter to both
668: ** methods. If the output buffer is not large enough, SQLITE_CANTOPEN
669: ** should be returned. As this is handled as a fatal error by SQLite,
670: ** vfs implementations should endevour to prevent this by setting
671: ** mxPathname to a sufficiently large value.
672: **
673: ** The xRandomness(), xSleep(), and xCurrentTime() interfaces
674: ** are not strictly a part of the filesystem, but they are
675: ** included in the VFS structure for completeness.
676: ** The xRandomness() function attempts to return nBytes bytes
677: ** of good-quality randomness into zOut. The return value is
678: ** the actual number of bytes of randomness obtained. The
679: ** xSleep() method cause the calling thread to sleep for at
680: ** least the number of microseconds given. The xCurrentTime()
681: ** method returns a Julian Day Number for the current date and
682: ** time.
683: */
684: typedef struct sqlite3_vfs sqlite3_vfs;
685: struct sqlite3_vfs {
686: int iVersion; /* Structure version number */
687: int szOsFile; /* Size of subclassed sqlite3_file */
688: int mxPathname; /* Maximum file pathname length */
689: sqlite3_vfs *pNext; /* Next registered VFS */
690: const char *zName; /* Name of this virtual file system */
691: void *pAppData; /* Pointer to application-specific data */
692: int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
693: int flags, int *pOutFlags);
694: int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
695: int (*xAccess)(sqlite3_vfs*, const char *zName, int flags);
696: int (*xGetTempname)(sqlite3_vfs*, int nOut, char *zOut);
697: int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
698: void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
699: void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
700: void *(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol);
701: void (*xDlClose)(sqlite3_vfs*, void*);
702: int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
703: int (*xSleep)(sqlite3_vfs*, int microseconds);
704: int (*xCurrentTime)(sqlite3_vfs*, double*);
705: /* New fields may be appended in figure versions. The iVersion
706: ** value will increment whenever this happens. */
707: };
708:
709: /*
710: ** CAPI3REF: Flags for the xAccess VFS method
711: **
712: ** These integer constants can be used as the third parameter to
713: ** the xAccess method of an [sqlite3_vfs] object. They determine
714: ** the kind of what kind of permissions the xAccess method is
715: ** looking for. With SQLITE_ACCESS_EXISTS, the xAccess method
716: ** simply checks to see if the file exists. With SQLITE_ACCESS_READWRITE,
717: ** the xAccess method checks to see if the file is both readable
718: ** and writable. With SQLITE_ACCESS_READ the xAccess method
719: ** checks to see if the file is readable.
720: */
721: #define SQLITE_ACCESS_EXISTS 0
722: #define SQLITE_ACCESS_READWRITE 1
723: #define SQLITE_ACCESS_READ 2
724:
725: /*
726: ** CAPI3REF: Enable Or Disable Extended Result Codes
727: **
728: ** This routine enables or disables the
729: ** [SQLITE_IOERR_READ | extended result codes] feature.
730: ** By default, SQLite API routines return one of only 26 integer
731: ** [SQLITE_OK | result codes]. When extended result codes
732: ** are enabled by this routine, the repetoire of result codes can be
733: ** much larger and can (hopefully) provide more detailed information
734: ** about the cause of an error.
735: **
736: ** The second argument is a boolean value that turns extended result
737: ** codes on and off. Extended result codes are off by default for
738: ** backwards compatibility with older versions of SQLite.
739: */
740: int sqlite3_extended_result_codes(sqlite3*, int onoff);
741:
742: /*
743: ** CAPI3REF: Last Insert Rowid
744: **
745: ** Each entry in an SQLite table has a unique 64-bit signed integer key
746: ** called the "rowid". The rowid is always available as an undeclared
747: ** column named ROWID, OID, or _ROWID_. If the table has a column of
748: ** type INTEGER PRIMARY KEY then that column is another an alias for the
749: ** rowid.
750: **
1.3 ! misha 751: ** This routine returns the rowid of the most recent successful INSERT into
1.2 misha 752: ** the database from the database connection given in the first
1.3 ! misha 753: ** argument. If no successful inserts have ever occurred on this database
1.2 misha 754: ** connection, zero is returned.
755: **
756: ** If an INSERT occurs within a trigger, then the rowid of the
757: ** inserted row is returned by this routine as long as the trigger
758: ** is running. But once the trigger terminates, the value returned
759: ** by this routine reverts to the last value inserted before the
760: ** trigger fired.
761: **
1.3 ! misha 762: ** An INSERT that fails due to a constraint violation is not a
! 763: ** successful insert and does not change the value returned by this
! 764: ** routine. Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
! 765: ** and INSERT OR ABORT make no changes to the return value of this
! 766: ** routine when their insertion fails. When INSERT OR REPLACE
! 767: ** encounters a constraint violation, it does not fail. The
! 768: ** INSERT continues to completion after deleting rows that caused
! 769: ** the constraint problem so INSERT OR REPLACE will always change
! 770: ** the return value of this interface.
! 771: **
1.2 misha 772: ** If another thread does a new insert on the same database connection
773: ** while this routine is running and thus changes the last insert rowid,
774: ** then the return value of this routine is undefined.
1.1 misha 775: */
1.2 misha 776: sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
1.1 misha 777:
778: /*
1.2 misha 779: ** CAPI3REF: Count The Number Of Rows Modified
780: **
1.1 misha 781: ** This function returns the number of database rows that were changed
1.2 misha 782: ** (or inserted or deleted) by the most recent SQL statement. Only
783: ** changes that are directly specified by the INSERT, UPDATE, or
784: ** DELETE statement are counted. Auxiliary changes caused by
785: ** triggers are not counted. Use the [sqlite3_total_changes()] function
786: ** to find the total number of changes including changes caused by triggers.
787: **
788: ** Within the body of a trigger, the sqlite3_changes() interface can be
789: ** called to find the number of
790: ** changes in the most recently completed INSERT, UPDATE, or DELETE
791: ** statement within the body of the trigger.
1.1 misha 792: **
793: ** All changes are counted, even if they were later undone by a
794: ** ROLLBACK or ABORT. Except, changes associated with creating and
795: ** dropping tables are not counted.
796: **
1.2 misha 797: ** If a callback invokes [sqlite3_exec()] or [sqlite3_step()] recursively,
798: ** then the changes in the inner, recursive call are counted together
799: ** with the changes in the outer call.
1.1 misha 800: **
801: ** SQLite implements the command "DELETE FROM table" without a WHERE clause
802: ** by dropping and recreating the table. (This is much faster than going
1.2 misha 803: ** through and deleting individual elements from the table.) Because of
1.1 misha 804: ** this optimization, the change count for "DELETE FROM table" will be
805: ** zero regardless of the number of elements that were originally in the
806: ** table. To get an accurate count of the number of rows deleted, use
807: ** "DELETE FROM table WHERE 1" instead.
1.2 misha 808: **
809: ** If another thread makes changes on the same database connection
810: ** while this routine is running then the return value of this routine
811: ** is undefined.
1.1 misha 812: */
813: int sqlite3_changes(sqlite3*);
814:
815: /*
1.2 misha 816: ** CAPI3REF: Total Number Of Rows Modified
817: ***
1.1 misha 818: ** This function returns the number of database rows that have been
819: ** modified by INSERT, UPDATE or DELETE statements since the database handle
820: ** was opened. This includes UPDATE, INSERT and DELETE statements executed
821: ** as part of trigger programs. All changes are counted as soon as the
822: ** statement that makes them is completed (when the statement handle is
1.2 misha 823: ** passed to [sqlite3_reset()] or [sqlite3_finalize()]).
824: **
825: ** See also the [sqlite3_change()] interface.
1.1 misha 826: **
827: ** SQLite implements the command "DELETE FROM table" without a WHERE clause
828: ** by dropping and recreating the table. (This is much faster than going
829: ** through and deleting individual elements form the table.) Because of
830: ** this optimization, the change count for "DELETE FROM table" will be
831: ** zero regardless of the number of elements that were originally in the
832: ** table. To get an accurate count of the number of rows deleted, use
833: ** "DELETE FROM table WHERE 1" instead.
1.2 misha 834: **
835: ** If another thread makes changes on the same database connection
836: ** while this routine is running then the return value of this routine
837: ** is undefined.
1.1 misha 838: */
839: int sqlite3_total_changes(sqlite3*);
840:
1.2 misha 841: /*
842: ** CAPI3REF: Interrupt A Long-Running Query
843: **
844: ** This function causes any pending database operation to abort and
1.1 misha 845: ** return at its earliest opportunity. This routine is typically
846: ** called in response to a user action such as pressing "Cancel"
847: ** or Ctrl-C where the user wants a long query operation to halt
848: ** immediately.
1.2 misha 849: **
850: ** It is safe to call this routine from a thread different from the
851: ** thread that is currently running the database operation. But it
852: ** is not safe to call this routine with a database connection that
853: ** is closed or might close before sqlite3_interrupt() returns.
854: **
855: ** The SQL operation that is interrupted will return [SQLITE_INTERRUPT].
856: ** If an interrupted operation was an update that is inside an
857: ** explicit transaction, then the entire transaction will be rolled
858: ** back automatically.
1.1 misha 859: */
860: void sqlite3_interrupt(sqlite3*);
861:
1.2 misha 862: /*
863: ** CAPI3REF: Determine If An SQL Statement Is Complete
864: **
865: ** These functions return true if the given input string comprises
1.1 misha 866: ** one or more complete SQL statements. For the sqlite3_complete() call,
867: ** the parameter must be a nul-terminated UTF-8 string. For
868: ** sqlite3_complete16(), a nul-terminated machine byte order UTF-16 string
869: ** is required.
870: **
1.2 misha 871: ** These routines are useful for command-line input to determine if the
872: ** currently entered text forms one or more complete SQL statements or
873: ** if additional input is needed before sending the statements into
874: ** SQLite for parsing. The algorithm is simple. If the
875: ** last token other than spaces and comments is a semicolon, then return
876: ** true. Actually, the algorithm is a little more complicated than that
877: ** in order to deal with triggers, but the basic idea is the same: the
878: ** statement is not complete unless it ends in a semicolon.
1.1 misha 879: */
880: int sqlite3_complete(const char *sql);
881: int sqlite3_complete16(const void *sql);
882:
883: /*
1.2 misha 884: ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
885: **
886: ** This routine identifies a callback function that might be invoked
887: ** whenever an attempt is made to open a database table
888: ** that another thread or process has locked.
889: ** If the busy callback is NULL, then [SQLITE_BUSY]
890: ** (or sometimes [SQLITE_IOERR_BLOCKED])
891: ** is returned immediately upon encountering the lock.
892: ** If the busy callback is not NULL, then the
893: ** callback will be invoked with two arguments. The
894: ** first argument to the handler is a copy of the void* pointer which
895: ** is the third argument to this routine. The second argument to
896: ** the handler is the number of times that the busy handler has
897: ** been invoked for this locking event. If the
898: ** busy callback returns 0, then no additional attempts are made to
899: ** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
900: ** If the callback returns non-zero, then another attempt is made to open the
901: ** database for reading and the cycle repeats.
902: **
903: ** The presence of a busy handler does not guarantee that
904: ** it will be invoked when there is lock contention.
905: ** If SQLite determines that invoking the busy handler could result in
906: ** a deadlock, it will return [SQLITE_BUSY] instead.
907: ** Consider a scenario where one process is holding a read lock that
908: ** it is trying to promote to a reserved lock and
909: ** a second process is holding a reserved lock that it is trying
910: ** to promote to an exclusive lock. The first process cannot proceed
911: ** because it is blocked by the second and the second process cannot
912: ** proceed because it is blocked by the first. If both processes
913: ** invoke the busy handlers, neither will make any progress. Therefore,
914: ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
915: ** will induce the first process to release its read lock and allow
916: ** the second process to proceed.
1.1 misha 917: **
918: ** The default busy callback is NULL.
919: **
1.2 misha 920: ** The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED] when
921: ** SQLite is in the middle of a large transaction where all the
922: ** changes will not fit into the in-memory cache. SQLite will
923: ** already hold a RESERVED lock on the database file, but it needs
924: ** to promote this lock to EXCLUSIVE so that it can spill cache
925: ** pages into the database file without harm to concurrent
926: ** readers. If it is unable to promote the lock, then the in-memory
927: ** cache will be left in an inconsistent state and so the error
928: ** code is promoted from the relatively benign [SQLITE_BUSY] to
929: ** the more severe [SQLITE_IOERR_BLOCKED]. This error code promotion
930: ** forces an automatic rollback of the changes. See the
931: ** <a href="http://www.sqlite.org/cvstrac/wiki?p=CorruptionFollowingBusyError">
932: ** CorruptionFollowingBusyError</a> wiki page for a discussion of why
933: ** this is important.
934: **
1.1 misha 935: ** Sqlite is re-entrant, so the busy handler may start a new query.
936: ** (It is not clear why anyone would every want to do this, but it
937: ** is allowed, in theory.) But the busy handler may not close the
938: ** database. Closing the database from a busy handler will delete
939: ** data structures out from under the executing query and will
1.2 misha 940: ** probably result in a segmentation fault or other runtime error.
941: **
942: ** There can only be a single busy handler defined for each database
943: ** connection. Setting a new busy handler clears any previous one.
944: ** Note that calling [sqlite3_busy_timeout()] will also set or clear
945: ** the busy handler.
946: **
947: ** When operating in [sqlite3_enable_shared_cache | shared cache mode],
948: ** only a single busy handler can be defined for each database file.
949: ** So if two database connections share a single cache, then changing
950: ** the busy handler on one connection will also change the busy
951: ** handler in the other connection. The busy handler is invoked
952: ** in the thread that was running when the SQLITE_BUSY was hit.
1.1 misha 953: */
954: int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
955:
956: /*
1.2 misha 957: ** CAPI3REF: Set A Busy Timeout
958: **
1.1 misha 959: ** This routine sets a busy handler that sleeps for a while when a
960: ** table is locked. The handler will sleep multiple times until
1.2 misha 961: ** at least "ms" milliseconds of sleeping have been done. After
962: ** "ms" milliseconds of sleeping, the handler returns 0 which
963: ** causes [sqlite3_step()] to return [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
1.1 misha 964: **
965: ** Calling this routine with an argument less than or equal to zero
966: ** turns off all busy handlers.
1.2 misha 967: **
968: ** There can only be a single busy handler for a particular database
969: ** connection. If another busy handler was defined
970: ** (using [sqlite3_busy_handler()]) prior to calling
971: ** this routine, that other busy handler is cleared.
1.1 misha 972: */
973: int sqlite3_busy_timeout(sqlite3*, int ms);
974:
975: /*
1.2 misha 976: ** CAPI3REF: Convenience Routines For Running Queries
977: **
978: ** This next routine is a convenience wrapper around [sqlite3_exec()].
1.1 misha 979: ** Instead of invoking a user-supplied callback for each row of the
980: ** result, this routine remembers each row of the result in memory
1.2 misha 981: ** obtained from [sqlite3_malloc()], then returns all of the result after the
1.1 misha 982: ** query has finished.
983: **
984: ** As an example, suppose the query result where this table:
985: **
1.2 misha 986: ** <blockquote><pre>
1.1 misha 987: ** Name | Age
988: ** -----------------------
989: ** Alice | 43
990: ** Bob | 28
991: ** Cindy | 21
1.2 misha 992: ** </pre></blockquote>
1.1 misha 993: **
994: ** If the 3rd argument were &azResult then after the function returns
995: ** azResult will contain the following data:
996: **
1.2 misha 997: ** <blockquote><pre>
998: ** azResult[0] = "Name";
999: ** azResult[1] = "Age";
1000: ** azResult[2] = "Alice";
1001: ** azResult[3] = "43";
1002: ** azResult[4] = "Bob";
1003: ** azResult[5] = "28";
1004: ** azResult[6] = "Cindy";
1005: ** azResult[7] = "21";
1006: ** </pre></blockquote>
1.1 misha 1007: **
1008: ** Notice that there is an extra row of data containing the column
1009: ** headers. But the *nrow return value is still 3. *ncolumn is
1010: ** set to 2. In general, the number of values inserted into azResult
1011: ** will be ((*nrow) + 1)*(*ncolumn).
1012: **
1013: ** After the calling function has finished using the result, it should
1014: ** pass the result data pointer to sqlite3_free_table() in order to
1015: ** release the memory that was malloc-ed. Because of the way the
1.2 misha 1016: ** [sqlite3_malloc()] happens, the calling function must not try to call
1017: ** [sqlite3_free()] directly. Only [sqlite3_free_table()] is able to release
1.1 misha 1018: ** the memory properly and safely.
1019: **
1.2 misha 1020: ** The return value of this routine is the same as from [sqlite3_exec()].
1.1 misha 1021: */
1022: int sqlite3_get_table(
1.2 misha 1023: sqlite3*, /* An open database */
1.1 misha 1024: const char *sql, /* SQL to be executed */
1025: char ***resultp, /* Result written to a char *[] that this points to */
1026: int *nrow, /* Number of result rows written here */
1027: int *ncolumn, /* Number of result columns written here */
1028: char **errmsg /* Error msg written here */
1029: );
1030: void sqlite3_free_table(char **result);
1031:
1032: /*
1.2 misha 1033: ** CAPI3REF: Formatted String Printing Functions
1034: **
1035: ** These routines are workalikes of the "printf()" family of functions
1036: ** from the standard C library.
1.1 misha 1037: **
1.2 misha 1038: ** The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
1039: ** results into memory obtained from [sqlite3_malloc()].
1040: ** The strings returned by these two routines should be
1041: ** released by [sqlite3_free()]. Both routines return a
1042: ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
1043: ** memory to hold the resulting string.
1044: **
1045: ** In sqlite3_snprintf() routine is similar to "snprintf()" from
1046: ** the standard C library. The result is written into the
1047: ** buffer supplied as the second parameter whose size is given by
1048: ** the first parameter. Note that the order of the
1049: ** first two parameters is reversed from snprintf(). This is an
1050: ** historical accident that cannot be fixed without breaking
1051: ** backwards compatibility. Note also that sqlite3_snprintf()
1052: ** returns a pointer to its buffer instead of the number of
1053: ** characters actually written into the buffer. We admit that
1054: ** the number of characters written would be a more useful return
1055: ** value but we cannot change the implementation of sqlite3_snprintf()
1056: ** now without breaking compatibility.
1057: **
1058: ** As long as the buffer size is greater than zero, sqlite3_snprintf()
1059: ** guarantees that the buffer is always zero-terminated. The first
1060: ** parameter "n" is the total size of the buffer, including space for
1061: ** the zero terminator. So the longest string that can be completely
1062: ** written will be n-1 characters.
1.1 misha 1063: **
1.2 misha 1064: ** These routines all implement some additional formatting
1065: ** options that are useful for constructing SQL statements.
1.1 misha 1066: ** All of the usual printf formatting options apply. In addition, there
1.2 misha 1067: ** is are "%q", "%Q", and "%z" options.
1068: **
1069: ** The %q option works like %s in that it substitutes a null-terminated
1.1 misha 1070: ** string from the argument list. But %q also doubles every '\'' character.
1071: ** %q is designed for use inside a string literal. By doubling each '\''
1072: ** character it escapes that character and allows it to be inserted into
1073: ** the string.
1074: **
1075: ** For example, so some string variable contains text as follows:
1076: **
1.2 misha 1077: ** <blockquote><pre>
1078: ** char *zText = "It's a happy day!";
1079: ** </pre></blockquote>
1080: **
1081: ** One can use this text in an SQL statement as follows:
1082: **
1083: ** <blockquote><pre>
1084: ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
1085: ** sqlite3_exec(db, zSQL, 0, 0, 0);
1086: ** sqlite3_free(zSQL);
1087: ** </pre></blockquote>
1.1 misha 1088: **
1089: ** Because the %q format string is used, the '\'' character in zText
1090: ** is escaped and the SQL generated is as follows:
1091: **
1.2 misha 1092: ** <blockquote><pre>
1093: ** INSERT INTO table1 VALUES('It''s a happy day!')
1094: ** </pre></blockquote>
1.1 misha 1095: **
1096: ** This is correct. Had we used %s instead of %q, the generated SQL
1097: ** would have looked like this:
1098: **
1.2 misha 1099: ** <blockquote><pre>
1100: ** INSERT INTO table1 VALUES('It's a happy day!');
1101: ** </pre></blockquote>
1.1 misha 1102: **
1103: ** This second example is an SQL syntax error. As a general rule you
1104: ** should always use %q instead of %s when inserting text into a string
1105: ** literal.
1.2 misha 1106: **
1107: ** The %Q option works like %q except it also adds single quotes around
1108: ** the outside of the total string. Or if the parameter in the argument
1109: ** list is a NULL pointer, %Q substitutes the text "NULL" (without single
1110: ** quotes) in place of the %Q option. So, for example, one could say:
1111: **
1112: ** <blockquote><pre>
1113: ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
1114: ** sqlite3_exec(db, zSQL, 0, 0, 0);
1115: ** sqlite3_free(zSQL);
1116: ** </pre></blockquote>
1117: **
1118: ** The code above will render a correct SQL statement in the zSQL
1119: ** variable even if the zText variable is a NULL pointer.
1120: **
1121: ** The "%z" formatting option works exactly like "%s" with the
1122: ** addition that after the string has been read and copied into
1123: ** the result, [sqlite3_free()] is called on the input string.
1.1 misha 1124: */
1125: char *sqlite3_mprintf(const char*,...);
1126: char *sqlite3_vmprintf(const char*, va_list);
1127: char *sqlite3_snprintf(int,char*,const char*, ...);
1128:
1129: /*
1.2 misha 1130: ** CAPI3REF: Memory Allocation Subsystem
1131: **
1132: ** The SQLite core uses these three routines for all of its own
1133: ** internal memory allocation needs. (See the exception below.)
1.3 ! misha 1134: **
1.2 misha 1135: ** The default implementation
1136: ** of the memory allocation subsystem uses the malloc(), realloc()
1137: ** and free() provided by the standard C library. However, if
1138: ** SQLite is compiled with the following C preprocessor macro
1139: **
1.3 ! misha 1140: ** <blockquote> SQLITE_MEMORY_SIZE=<i>NNN</i> </blockquote>
1.2 misha 1141: **
1.3 ! misha 1142: ** where <i>NNN</i> is an integer, then SQLite create a static
! 1143: ** array of at least <i>NNN</i> bytes in size and use that array
! 1144: ** for all of its dynamic memory allocation needs.
! 1145: **
! 1146: ** In SQLite version 3.5.0 and 3.5.1, it was possible to define
! 1147: ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
! 1148: ** implementation of these routines to be omitted. That capability
! 1149: ** is no longer provided. Only built-in memory allocators can be
! 1150: ** used.
1.2 misha 1151: **
1152: ** <b>Exception:</b> The windows OS interface layer calls
1153: ** the system malloc() and free() directly when converting
1154: ** filenames between the UTF-8 encoding used by SQLite
1155: ** and whatever filename encoding is used by the particular windows
1156: ** installation. Memory allocation errors are detected, but
1157: ** they are reported back as [SQLITE_CANTOPEN] or
1158: ** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
1159: */
1160: void *sqlite3_malloc(int);
1161: void *sqlite3_realloc(void*, int);
1162: void sqlite3_free(void*);
1163:
1164: /*
1165: ** CAPI3REF: Memory Allocator Statistics
1166: **
1167: ** In addition to the basic three allocation routines
1168: ** [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()],
1169: ** the memory allocation subsystem included with the SQLite
1170: ** sources provides the interfaces shown below.
1171: **
1172: ** The first of these two routines returns the amount of memory
1173: ** currently outstanding (malloced but not freed). The second
1174: ** returns the largest instantaneous amount of outstanding
1175: ** memory. The highwater mark is reset if the argument is
1176: ** true.
1177: **
1.3 ! misha 1178: ** The value returned may or may not include allocation
! 1179: ** overhead, depending on which built-in memory allocator
! 1180: ** implementation is used.
1.2 misha 1181: */
1182: sqlite3_int64 sqlite3_memory_used(void);
1183: sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
1184:
1185: /*
1186: ** CAPI3REF: Compile-Time Authorization Callbacks
1187: ***
1188: ** This routine registers a authorizer callback with the SQLite library.
1189: ** The authorizer callback is invoked as SQL statements are being compiled
1190: ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
1191: ** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. At various
1192: ** points during the compilation process, as logic is being created
1193: ** to perform various actions, the authorizer callback is invoked to
1194: ** see if those actions are allowed. The authorizer callback should
1195: ** return SQLITE_OK to allow the action, [SQLITE_IGNORE] to disallow the
1196: ** specific action but allow the SQL statement to continue to be
1197: ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
1198: ** rejected with an error.
1199: **
1200: ** Depending on the action, the [SQLITE_IGNORE] and [SQLITE_DENY] return
1201: ** codes might mean something different or they might mean the same
1202: ** thing. If the action is, for example, to perform a delete opertion,
1203: ** then [SQLITE_IGNORE] and [SQLITE_DENY] both cause the statement compilation
1204: ** to fail with an error. But if the action is to read a specific column
1205: ** from a specific table, then [SQLITE_DENY] will cause the entire
1206: ** statement to fail but [SQLITE_IGNORE] will cause a NULL value to be
1207: ** read instead of the actual column value.
1208: **
1209: ** The first parameter to the authorizer callback is a copy of
1210: ** the third parameter to the sqlite3_set_authorizer() interface.
1211: ** The second parameter to the callback is an integer
1212: ** [SQLITE_COPY | action code] that specifies the particular action
1213: ** to be authorized. The available action codes are
1214: ** [SQLITE_COPY | documented separately]. The third through sixth
1215: ** parameters to the callback are strings that contain additional
1216: ** details about the action to be authorized.
1217: **
1218: ** An authorizer is used when preparing SQL statements from an untrusted
1219: ** source, to ensure that the SQL statements do not try to access data
1220: ** that they are not allowed to see, or that they do not try to
1221: ** execute malicious statements that damage the database. For
1222: ** example, an application may allow a user to enter arbitrary
1223: ** SQL queries for evaluation by a database. But the application does
1224: ** not want the user to be able to make arbitrary changes to the
1225: ** database. An authorizer could then be put in place while the
1226: ** user-entered SQL is being prepared that disallows everything
1227: ** except SELECT statements.
1228: **
1229: ** Only a single authorizer can be in place on a database connection
1230: ** at a time. Each call to sqlite3_set_authorizer overrides the
1231: ** previous call. A NULL authorizer means that no authorization
1232: ** callback is invoked. The default authorizer is NULL.
1233: **
1234: ** Note that the authorizer callback is invoked only during
1235: ** [sqlite3_prepare()] or its variants. Authorization is not
1236: ** performed during statement evaluation in [sqlite3_step()].
1.1 misha 1237: */
1238: int sqlite3_set_authorizer(
1239: sqlite3*,
1240: int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
1241: void *pUserData
1242: );
1243:
1244: /*
1.2 misha 1245: ** CAPI3REF: Authorizer Return Codes
1246: **
1247: ** The [sqlite3_set_authorizer | authorizer callback function] must
1248: ** return either [SQLITE_OK] or one of these two constants in order
1249: ** to signal SQLite whether or not the action is permitted. See the
1250: ** [sqlite3_set_authorizer | authorizer documentation] for additional
1251: ** information.
1252: */
1253: #define SQLITE_DENY 1 /* Abort the SQL statement with an error */
1254: #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
1255:
1256: /*
1257: ** CAPI3REF: Authorizer Action Codes
1258: **
1259: ** The [sqlite3_set_authorizer()] interface registers a callback function
1260: ** that is invoked to authorizer certain SQL statement actions. The
1261: ** second parameter to the callback is an integer code that specifies
1262: ** what action is being authorized. These are the integer action codes that
1263: ** the authorizer callback may be passed.
1264: **
1265: ** These action code values signify what kind of operation is to be
1266: ** authorized. The 3rd and 4th parameters to the authorization callback
1267: ** function will be parameters or NULL depending on which of these
1268: ** codes is used as the second parameter. The 5th parameter to the
1269: ** authorizer callback is the name of the database ("main", "temp",
1270: ** etc.) if applicable. The 6th parameter to the authorizer callback
1.1 misha 1271: ** is the name of the inner-most trigger or view that is responsible for
1272: ** the access attempt or NULL if this access attempt is directly from
1.2 misha 1273: ** top-level SQL code.
1.1 misha 1274: */
1.2 misha 1275: /******************************************* 3rd ************ 4th ***********/
1.1 misha 1276: #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
1277: #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
1278: #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
1279: #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
1280: #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
1281: #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
1282: #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
1283: #define SQLITE_CREATE_VIEW 8 /* View Name NULL */
1284: #define SQLITE_DELETE 9 /* Table Name NULL */
1285: #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
1286: #define SQLITE_DROP_TABLE 11 /* Table Name NULL */
1287: #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
1288: #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
1289: #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
1290: #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
1291: #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
1292: #define SQLITE_DROP_VIEW 17 /* View Name NULL */
1293: #define SQLITE_INSERT 18 /* Table Name NULL */
1294: #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
1295: #define SQLITE_READ 20 /* Table Name Column Name */
1296: #define SQLITE_SELECT 21 /* NULL NULL */
1297: #define SQLITE_TRANSACTION 22 /* NULL NULL */
1298: #define SQLITE_UPDATE 23 /* Table Name Column Name */
1299: #define SQLITE_ATTACH 24 /* Filename NULL */
1300: #define SQLITE_DETACH 25 /* Database Name NULL */
1.2 misha 1301: #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
1302: #define SQLITE_REINDEX 27 /* Index Name NULL */
1303: #define SQLITE_ANALYZE 28 /* Table Name NULL */
1304: #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
1305: #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
1306: #define SQLITE_FUNCTION 31 /* Function Name NULL */
1307: #define SQLITE_COPY 0 /* No longer used */
1308:
1309: /*
1310: ** CAPI3REF: Tracing And Profiling Functions
1311: **
1312: ** These routines register callback functions that can be used for
1313: ** tracing and profiling the execution of SQL statements.
1314: ** The callback function registered by sqlite3_trace() is invoked
1315: ** at the first [sqlite3_step()] for the evaluation of an SQL statement.
1316: ** The callback function registered by sqlite3_profile() is invoked
1317: ** as each SQL statement finishes and includes
1318: ** information on how long that statement ran.
1319: **
1320: ** The sqlite3_profile() API is currently considered experimental and
1321: ** is subject to change.
1.1 misha 1322: */
1323: void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
1.2 misha 1324: void *sqlite3_profile(sqlite3*,
1325: void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
1.1 misha 1326:
1327: /*
1.2 misha 1328: ** CAPI3REF: Query Progress Callbacks
1329: **
1.1 misha 1330: ** This routine configures a callback function - the progress callback - that
1.2 misha 1331: ** is invoked periodically during long running calls to [sqlite3_exec()],
1332: ** [sqlite3_step()] and [sqlite3_get_table()]. An example use for this
1333: ** interface is to keep a GUI updated during a large query.
1.1 misha 1334: **
1335: ** The progress callback is invoked once for every N virtual machine opcodes,
1336: ** where N is the second argument to this function. The progress callback
1337: ** itself is identified by the third argument to this function. The fourth
1338: ** argument to this function is a void pointer passed to the progress callback
1339: ** function each time it is invoked.
1340: **
1.2 misha 1341: ** If a call to [sqlite3_exec()], [sqlite3_step()], or [sqlite3_get_table()]
1342: ** results in fewer than N opcodes being executed, then the progress
1343: ** callback is never invoked.
1.1 misha 1344: **
1.2 misha 1345: ** Only a single progress callback function may be registered for each
1346: ** open database connection. Every call to sqlite3_progress_handler()
1347: ** overwrites the results of the previous call.
1.1 misha 1348: ** To remove the progress callback altogether, pass NULL as the third
1349: ** argument to this function.
1350: **
1351: ** If the progress callback returns a result other than 0, then the current
1.2 misha 1352: ** query is immediately terminated and any database changes rolled back.
1353: ** The containing [sqlite3_exec()], [sqlite3_step()], or
1354: ** [sqlite3_get_table()] call returns SQLITE_INTERRUPT. This feature
1355: ** can be used, for example, to implement the "Cancel" button on a
1356: ** progress dialog box in a GUI.
1.1 misha 1357: */
1358: void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
1359:
1360: /*
1.2 misha 1361: ** CAPI3REF: Opening A New Database Connection
1.1 misha 1362: **
1363: ** Open the sqlite database file "filename". The "filename" is UTF-8
1.2 misha 1364: ** encoded for [sqlite3_open()] and [sqlite3_open_v2()] and UTF-16 encoded
1365: ** in the native byte order for [sqlite3_open16()].
1366: ** An [sqlite3*] handle is returned in *ppDb, even
1.1 misha 1367: ** if an error occurs. If the database is opened (or created) successfully,
1.2 misha 1368: ** then [SQLITE_OK] is returned. Otherwise an error code is returned. The
1369: ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
1.1 misha 1370: ** an English language description of the error.
1371: **
1.2 misha 1372: ** The default encoding for the database will be UTF-8 if
1373: ** [sqlite3_open()] or [sqlite3_open_v2()] is called and
1374: ** UTF-16 if [sqlite3_open16()] is used.
1.1 misha 1375: **
1376: ** Whether or not an error occurs when it is opened, resources associated
1.2 misha 1377: ** with the [sqlite3*] handle should be released by passing it to
1378: ** [sqlite3_close()] when it is no longer required.
1379: **
1380: ** The [sqlite3_open_v2()] interface works like [sqlite3_open()] except that
1381: ** provides two additional parameters for additional control over the
1382: ** new database connection. The flags parameter can be one of:
1383: **
1384: ** <ol>
1385: ** <li> [SQLITE_OPEN_READONLY]
1386: ** <li> [SQLITE_OPEN_READWRITE]
1387: ** <li> [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]
1388: ** </ol>
1389: **
1390: ** The first value opens the database read-only. If the database does
1391: ** not previously exist, an error is returned. The second option opens
1392: ** the database for reading and writing if possible, or reading only if
1393: ** if the file is write protected. In either case the database must already
1394: ** exist or an error is returned. The third option opens the database
1395: ** for reading and writing and creates it if it does not already exist.
1396: ** The third options is behavior that is always used for [sqlite3_open()]
1397: ** and [sqlite3_open16()].
1398: **
1399: ** If the filename is ":memory:", then an private
1400: ** in-memory database is created for the connection. This in-memory
1401: ** database will vanish when the database connection is closed. Future
1402: ** version of SQLite might make use of additional special filenames
1403: ** that begin with the ":" character. It is recommended that
1404: ** when a database filename really does begin with
1405: ** ":" that you prefix the filename with a pathname like "./" to
1406: ** avoid ambiguity.
1407: **
1408: ** If the filename is an empty string, then a private temporary
1409: ** on-disk database will be created. This private database will be
1410: ** automatically deleted as soon as the database connection is closed.
1411: **
1412: ** The fourth parameter to sqlite3_open_v2() is the name of the
1413: ** [sqlite3_vfs] object that defines the operating system
1414: ** interface that the new database connection should use. If the
1415: ** fourth parameter is a NULL pointer then the default [sqlite3_vfs]
1416: ** object is used.
1417: **
1418: ** <b>Note to windows users:</b> The encoding used for the filename argument
1419: ** of [sqlite3_open()] and [sqlite3_open_v2()] must be UTF-8, not whatever
1420: ** codepage is currently defined. Filenames containing international
1421: ** characters must be converted to UTF-8 prior to passing them into
1422: ** [sqlite3_open()] or [sqlite3_open_v2()].
1.1 misha 1423: */
1424: int sqlite3_open(
1425: const char *filename, /* Database filename (UTF-8) */
1426: sqlite3 **ppDb /* OUT: SQLite db handle */
1427: );
1428: int sqlite3_open16(
1429: const void *filename, /* Database filename (UTF-16) */
1430: sqlite3 **ppDb /* OUT: SQLite db handle */
1431: );
1.2 misha 1432: int sqlite3_open_v2(
1433: const char *filename, /* Database filename (UTF-8) */
1434: sqlite3 **ppDb, /* OUT: SQLite db handle */
1435: int flags, /* Flags */
1436: const char *zVfs /* Name of VFS module to use */
1437: );
1.1 misha 1438:
1439: /*
1.2 misha 1440: ** CAPI3REF: Error Codes And Messages
1441: **
1442: ** The sqlite3_errcode() interface returns the numeric
1443: ** [SQLITE_OK | result code] or [SQLITE_IOERR_READ | extended result code]
1444: ** for the most recent failed sqlite3_* API call associated
1445: ** with [sqlite3] handle 'db'. If a prior API call failed but the
1446: ** most recent API call succeeded, the return value from sqlite3_errcode()
1447: ** is undefined.
1448: **
1449: ** The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
1450: ** text that describes the error, as either UTF8 or UTF16 respectively.
1451: ** Memory to hold the error message string is managed internally. The
1452: ** string may be overwritten or deallocated by subsequent calls to SQLite
1453: ** interface functions.
1.1 misha 1454: **
1455: ** Calls to many sqlite3_* functions set the error code and string returned
1.2 misha 1456: ** by [sqlite3_errcode()], [sqlite3_errmsg()], and [sqlite3_errmsg16()]
1457: ** (overwriting the previous values). Note that calls to [sqlite3_errcode()],
1458: ** [sqlite3_errmsg()], and [sqlite3_errmsg16()] themselves do not affect the
1459: ** results of future invocations. Calls to API routines that do not return
1460: ** an error code (example: [sqlite3_data_count()]) do not
1461: ** change the error code returned by this routine. Interfaces that are
1462: ** not associated with a specific database connection (examples:
1463: ** [sqlite3_mprintf()] or [sqlite3_enable_shared_cache()] do not change
1464: ** the return code.
1.1 misha 1465: **
1466: ** Assuming no other intervening sqlite3_* API calls are made, the error
1467: ** code returned by this function is associated with the same error as
1.2 misha 1468: ** the strings returned by [sqlite3_errmsg()] and [sqlite3_errmsg16()].
1.1 misha 1469: */
1470: int sqlite3_errcode(sqlite3 *db);
1.2 misha 1471: const char *sqlite3_errmsg(sqlite3*);
1472: const void *sqlite3_errmsg16(sqlite3*);
1.1 misha 1473:
1474: /*
1.2 misha 1475: ** CAPI3REF: SQL Statement Object
1476: **
1477: ** Instance of this object represent single SQL statements. This
1478: ** is variously known as a "prepared statement" or a
1479: ** "compiled SQL statement" or simply as a "statement".
1480: **
1481: ** The life of a statement object goes something like this:
1.1 misha 1482: **
1.2 misha 1483: ** <ol>
1484: ** <li> Create the object using [sqlite3_prepare_v2()] or a related
1485: ** function.
1486: ** <li> Bind values to host parameters using
1487: ** [sqlite3_bind_blob | sqlite3_bind_* interfaces].
1488: ** <li> Run the SQL by calling [sqlite3_step()] one or more times.
1489: ** <li> Reset the statement using [sqlite3_reset()] then go back
1490: ** to step 2. Do this zero or more times.
1491: ** <li> Destroy the object using [sqlite3_finalize()].
1492: ** </ol>
1.1 misha 1493: **
1.2 misha 1494: ** Refer to documentation on individual methods above for additional
1495: ** information.
1.1 misha 1496: */
1497: typedef struct sqlite3_stmt sqlite3_stmt;
1498:
1499: /*
1.2 misha 1500: ** CAPI3REF: Compiling An SQL Statement
1501: **
1.1 misha 1502: ** To execute an SQL query, it must first be compiled into a byte-code
1.2 misha 1503: ** program using one of these routines.
1504: **
1505: ** The first argument "db" is an [sqlite3 | SQLite database handle]
1506: ** obtained from a prior call to [sqlite3_open()], [sqlite3_open_v2()]
1507: ** or [sqlite3_open16()].
1508: ** The second argument "zSql" is the statement to be compiled, encoded
1509: ** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
1510: ** interfaces uses UTF-8 and sqlite3_prepare16() and sqlite3_prepare16_v2()
1511: ** use UTF-16.
1512: **
1513: ** If the nByte argument is less
1514: ** than zero, then zSql is read up to the first zero terminator. If
1515: ** nByte is non-negative, then it is the maximum number of
1516: ** bytes read from zSql. When nByte is non-negative, the
1517: ** zSql string ends at either the first '\000' character or
1518: ** until the nByte-th byte, whichever comes first.
1.1 misha 1519: **
1520: ** *pzTail is made to point to the first byte past the end of the first
1521: ** SQL statement in zSql. This routine only compiles the first statement
1522: ** in zSql, so *pzTail is left pointing to what remains uncompiled.
1523: **
1.2 misha 1524: ** *ppStmt is left pointing to a compiled
1525: ** [sqlite3_stmt | SQL statement structure] that can be
1526: ** executed using [sqlite3_step()]. Or if there is an error, *ppStmt may be
1.1 misha 1527: ** set to NULL. If the input text contained no SQL (if the input is and
1.2 misha 1528: ** empty string or a comment) then *ppStmt is set to NULL. The calling
1529: ** procedure is responsible for deleting the compiled SQL statement
1530: ** using [sqlite3_finalize()] after it has finished with it.
1531: **
1532: ** On success, [SQLITE_OK] is returned. Otherwise an
1533: ** [SQLITE_ERROR | error code] is returned.
1534: **
1535: ** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
1536: ** recommended for all new programs. The two older interfaces are retained
1537: ** for backwards compatibility, but their use is discouraged.
1538: ** In the "v2" interfaces, the prepared statement
1539: ** that is returned (the [sqlite3_stmt] object) contains a copy of the
1540: ** original SQL text. This causes the [sqlite3_step()] interface to
1541: ** behave a differently in two ways:
1542: **
1543: ** <ol>
1544: ** <li>
1545: ** If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
1546: ** always used to do, [sqlite3_step()] will automatically recompile the SQL
1547: ** statement and try to run it again. If the schema has changed in a way
1548: ** that makes the statement no longer valid, [sqlite3_step()] will still
1549: ** return [SQLITE_SCHEMA]. But unlike the legacy behavior, [SQLITE_SCHEMA] is
1550: ** now a fatal error. Calling [sqlite3_prepare_v2()] again will not make the
1551: ** error go away. Note: use [sqlite3_errmsg()] to find the text of the parsing
1552: ** error that results in an [SQLITE_SCHEMA] return.
1553: ** </li>
1554: **
1555: ** <li>
1556: ** When an error occurs,
1557: ** [sqlite3_step()] will return one of the detailed
1558: ** [SQLITE_ERROR | result codes] or
1559: ** [SQLITE_IOERR_READ | extended result codes] such as directly.
1560: ** The legacy behavior was that [sqlite3_step()] would only return a generic
1561: ** [SQLITE_ERROR] result code and you would have to make a second call to
1562: ** [sqlite3_reset()] in order to find the underlying cause of the problem.
1563: ** With the "v2" prepare interfaces, the underlying reason for the error is
1564: ** returned immediately.
1565: ** </li>
1566: ** </ol>
1.1 misha 1567: */
1568: int sqlite3_prepare(
1569: sqlite3 *db, /* Database handle */
1570: const char *zSql, /* SQL statement, UTF-8 encoded */
1.2 misha 1571: int nByte, /* Maximum length of zSql in bytes. */
1572: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
1573: const char **pzTail /* OUT: Pointer to unused portion of zSql */
1574: );
1575: int sqlite3_prepare_v2(
1576: sqlite3 *db, /* Database handle */
1577: const char *zSql, /* SQL statement, UTF-8 encoded */
1578: int nByte, /* Maximum length of zSql in bytes. */
1.1 misha 1579: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
1580: const char **pzTail /* OUT: Pointer to unused portion of zSql */
1581: );
1582: int sqlite3_prepare16(
1583: sqlite3 *db, /* Database handle */
1584: const void *zSql, /* SQL statement, UTF-16 encoded */
1.2 misha 1585: int nByte, /* Maximum length of zSql in bytes. */
1586: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
1587: const void **pzTail /* OUT: Pointer to unused portion of zSql */
1588: );
1589: int sqlite3_prepare16_v2(
1590: sqlite3 *db, /* Database handle */
1591: const void *zSql, /* SQL statement, UTF-16 encoded */
1592: int nByte, /* Maximum length of zSql in bytes. */
1.1 misha 1593: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
1594: const void **pzTail /* OUT: Pointer to unused portion of zSql */
1595: );
1596:
1597: /*
1.2 misha 1598: ** CAPI3REF: Dynamically Typed Value Object
1599: **
1600: ** SQLite uses dynamic typing for the values it stores. Values can
1601: ** be integers, floating point values, strings, BLOBs, or NULL. When
1602: ** passing around values internally, each value is represented as
1603: ** an instance of the sqlite3_value object.
1604: */
1605: typedef struct Mem sqlite3_value;
1606:
1607: /*
1608: ** CAPI3REF: SQL Function Context Object
1609: **
1610: ** The context in which an SQL function executes is stored in an
1611: ** sqlite3_context object. A pointer to such an object is the
1612: ** first parameter to user-defined SQL functions.
1.1 misha 1613: */
1614: typedef struct sqlite3_context sqlite3_context;
1615:
1616: /*
1.2 misha 1617: ** CAPI3REF: Binding Values To Prepared Statements
1618: **
1619: ** In the SQL strings input to [sqlite3_prepare_v2()] and its variants,
1620: ** one or more literals can be replace by a parameter in one of these
1621: ** forms:
1622: **
1623: ** <ul>
1624: ** <li> ?
1625: ** <li> ?NNN
1626: ** <li> :AAA
1627: ** <li> @AAA
1628: ** <li> $VVV
1629: ** </ul>
1630: **
1631: ** In the parameter forms shown above NNN is an integer literal,
1632: ** AAA is an alphanumeric identifier and VVV is a variable name according
1633: ** to the syntax rules of the TCL programming language.
1634: ** The values of these parameters (also called "host parameter names")
1635: ** can be set using the sqlite3_bind_*() routines defined here.
1636: **
1637: ** The first argument to the sqlite3_bind_*() routines always is a pointer
1638: ** to the [sqlite3_stmt] object returned from [sqlite3_prepare_v2()] or
1639: ** its variants. The second
1640: ** argument is the index of the parameter to be set. The first parameter has
1641: ** an index of 1. When the same named parameter is used more than once, second
1642: ** and subsequent
1643: ** occurrences have the same index as the first occurrence. The index for
1644: ** named parameters can be looked up using the
1645: ** [sqlite3_bind_parameter_name()] API if desired. The index for "?NNN"
1646: ** parametes is the value of NNN.
1647: ** The NNN value must be between 1 and the compile-time
1648: ** parameter SQLITE_MAX_VARIABLE_NUMBER (default value: 999).
1649: ** See <a href="limits.html">limits.html</a> for additional information.
1650: **
1651: ** The third argument is the value to bind to the parameter.
1652: **
1653: ** In those
1654: ** routines that have a fourth argument, its value is the number of bytes
1655: ** in the parameter. To be clear: the value is the number of bytes in the
1656: ** string, not the number of characters. The number
1657: ** of bytes does not include the zero-terminator at the end of strings.
1658: ** If the fourth parameter is negative, the length of the string is
1659: ** number of bytes up to the first zero terminator.
1.1 misha 1660: **
1.2 misha 1661: ** The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
1.1 misha 1662: ** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
1663: ** text after SQLite has finished with it. If the fifth argument is the
1.2 misha 1664: ** special value [SQLITE_STATIC], then the library assumes that the information
1.1 misha 1665: ** is in static, unmanaged space and does not need to be freed. If the
1.2 misha 1666: ** fifth argument has the value [SQLITE_TRANSIENT], then SQLite makes its
1667: ** own private copy of the data immediately, before the sqlite3_bind_*()
1668: ** routine returns.
1669: **
1670: ** The sqlite3_bind_zeroblob() routine binds a BLOB of length n that
1671: ** is filled with zeros. A zeroblob uses a fixed amount of memory
1672: ** (just an integer to hold it size) while it is being processed.
1673: ** Zeroblobs are intended to serve as place-holders for BLOBs whose
1674: ** content is later written using
1675: ** [sqlite3_blob_open | increment BLOB I/O] routines. A negative
1676: ** value for the zeroblob results in a zero-length BLOB.
1677: **
1678: ** The sqlite3_bind_*() routines must be called after
1679: ** [sqlite3_prepare_v2()] (and its variants) or [sqlite3_reset()] and
1680: ** before [sqlite3_step()].
1681: ** Bindings are not cleared by the [sqlite3_reset()] routine.
1682: ** Unbound parameters are interpreted as NULL.
1683: **
1684: ** These routines return [SQLITE_OK] on success or an error code if
1685: ** anything goes wrong. [SQLITE_RANGE] is returned if the parameter
1686: ** index is out of range. [SQLITE_NOMEM] is returned if malloc fails.
1687: ** [SQLITE_MISUSE] is returned if these routines are called on a virtual
1688: ** machine that is the wrong state or which has already been finalized.
1.1 misha 1689: */
1690: int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
1691: int sqlite3_bind_double(sqlite3_stmt*, int, double);
1692: int sqlite3_bind_int(sqlite3_stmt*, int, int);
1.2 misha 1693: int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
1.1 misha 1694: int sqlite3_bind_null(sqlite3_stmt*, int);
1695: int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
1696: int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
1697: int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
1.2 misha 1698: int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
1.1 misha 1699:
1700: /*
1.2 misha 1701: ** CAPI3REF: Number Of Host Parameters
1702: **
1703: ** Return the largest host parameter index in the precompiled statement given
1704: ** as the argument. When the host parameters are of the forms like ":AAA"
1705: ** or "?", then they are assigned sequential increasing numbers beginning
1706: ** with one, so the value returned is the number of parameters. However
1707: ** if the same host parameter name is used multiple times, each occurrance
1708: ** is given the same number, so the value returned in that case is the number
1709: ** of unique host parameter names. If host parameters of the form "?NNN"
1710: ** are used (where NNN is an integer) then there might be gaps in the
1711: ** numbering and the value returned by this interface is the index of the
1712: ** host parameter with the largest index value.
1713: **
1714: ** The prepared statement must not be [sqlite3_finalize | finalized]
1715: ** prior to this routine returnning. Otherwise the results are undefined
1716: ** and probably undesirable.
1.1 misha 1717: */
1718: int sqlite3_bind_parameter_count(sqlite3_stmt*);
1719:
1720: /*
1.2 misha 1721: ** CAPI3REF: Name Of A Host Parameter
1722: **
1723: ** This routine returns a pointer to the name of the n-th parameter in a
1724: ** [sqlite3_stmt | prepared statement].
1725: ** Host parameters of the form ":AAA" or "@AAA" or "$VVV" have a name
1726: ** which is the string ":AAA" or "@AAA" or "$VVV".
1727: ** In other words, the initial ":" or "$" or "@"
1728: ** is included as part of the name.
1729: ** Parameters of the form "?" or "?NNN" have no name.
1730: **
1731: ** The first bound parameter has an index of 1, not 0.
1732: **
1733: ** If the value n is out of range or if the n-th parameter is nameless,
1734: ** then NULL is returned. The returned string is always in the
1735: ** UTF-8 encoding even if the named parameter was originally specified
1736: ** as UTF-16 in [sqlite3_prepare16()] or [sqlite3_prepare16_v2()].
1.1 misha 1737: */
1738: const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
1739:
1740: /*
1.2 misha 1741: ** CAPI3REF: Index Of A Parameter With A Given Name
1742: **
1743: ** This routine returns the index of a host parameter with the given name.
1744: ** The name must match exactly. If no parameter with the given name is
1745: ** found, return 0. Parameter names must be UTF8.
1.1 misha 1746: */
1747: int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
1748:
1749: /*
1.2 misha 1750: ** CAPI3REF: Reset All Bindings On A Prepared Statement
1751: **
1752: ** Contrary to the intuition of many, [sqlite3_reset()] does not
1753: ** reset the [sqlite3_bind_blob | bindings] on a
1754: ** [sqlite3_stmt | prepared statement]. Use this routine to
1755: ** reset all host parameters to NULL.
1.1 misha 1756: */
1.2 misha 1757: int sqlite3_clear_bindings(sqlite3_stmt*);
1.1 misha 1758:
1759: /*
1.2 misha 1760: ** CAPI3REF: Number Of Columns In A Result Set
1761: **
1762: ** Return the number of columns in the result set returned by the
1763: ** [sqlite3_stmt | compiled SQL statement]. This routine returns 0
1764: ** if pStmt is an SQL statement that does not return data (for
1765: ** example an UPDATE).
1766: */
1767: int sqlite3_column_count(sqlite3_stmt *pStmt);
1.1 misha 1768:
1769: /*
1.2 misha 1770: ** CAPI3REF: Column Names In A Result Set
1771: **
1772: ** These routines return the name assigned to a particular column
1773: ** in the result set of a SELECT statement. The sqlite3_column_name()
1774: ** interface returns a pointer to a UTF8 string and sqlite3_column_name16()
1775: ** returns a pointer to a UTF16 string. The first parameter is the
1776: ** [sqlite3_stmt | prepared statement] that implements the SELECT statement.
1777: ** The second parameter is the column number. The left-most column is
1778: ** number 0.
1779: **
1780: ** The returned string pointer is valid until either the
1781: ** [sqlite3_stmt | prepared statement] is destroyed by [sqlite3_finalize()]
1782: ** or until the next call sqlite3_column_name() or sqlite3_column_name16()
1783: ** on the same column.
1784: **
1785: ** If sqlite3_malloc() fails during the processing of either routine
1786: ** (for example during a conversion from UTF-8 to UTF-16) then a
1787: ** NULL pointer is returned.
1788: */
1789: const char *sqlite3_column_name(sqlite3_stmt*, int N);
1790: const void *sqlite3_column_name16(sqlite3_stmt*, int N);
1791:
1792: /*
1793: ** CAPI3REF: Source Of Data In A Query Result
1794: **
1795: ** These routines provide a means to determine what column of what
1796: ** table in which database a result of a SELECT statement comes from.
1797: ** The name of the database or table or column can be returned as
1798: ** either a UTF8 or UTF16 string. The _database_ routines return
1799: ** the database name, the _table_ routines return the table name, and
1800: ** the origin_ routines return the column name.
1801: ** The returned string is valid until
1802: ** the [sqlite3_stmt | prepared statement] is destroyed using
1803: ** [sqlite3_finalize()] or until the same information is requested
1804: ** again in a different encoding.
1805: **
1806: ** The names returned are the original un-aliased names of the
1807: ** database, table, and column.
1808: **
1809: ** The first argument to the following calls is a
1810: ** [sqlite3_stmt | compiled SQL statement].
1811: ** These functions return information about the Nth column returned by
1812: ** the statement, where N is the second function argument.
1813: **
1814: ** If the Nth column returned by the statement is an expression
1815: ** or subquery and is not a column value, then all of these functions
1816: ** return NULL. Otherwise, they return the
1817: ** name of the attached database, table and column that query result
1818: ** column was extracted from.
1819: **
1820: ** As with all other SQLite APIs, those postfixed with "16" return UTF-16
1821: ** encoded strings, the other functions return UTF-8.
1822: **
1823: ** These APIs are only available if the library was compiled with the
1824: ** SQLITE_ENABLE_COLUMN_METADATA preprocessor symbol defined.
1825: **
1826: ** If two or more threads call one or more of these routines against the same
1827: ** prepared statement and column at the same time then the results are
1828: ** undefined.
1829: */
1830: const char *sqlite3_column_database_name(sqlite3_stmt*,int);
1831: const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
1832: const char *sqlite3_column_table_name(sqlite3_stmt*,int);
1833: const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
1834: const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
1835: const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
1836:
1837: /*
1838: ** CAPI3REF: Declared Datatype Of A Query Result
1839: **
1840: ** The first parameter is a [sqlite3_stmt | compiled SQL statement].
1841: ** If this statement is a SELECT statement and the Nth column of the
1842: ** returned result set of that SELECT is a table column (not an
1843: ** expression or subquery) then the declared type of the table
1844: ** column is returned. If the Nth column of the result set is an
1845: ** expression or subquery, then a NULL pointer is returned.
1846: ** The returned string is always UTF-8 encoded. For example, in
1847: ** the database schema:
1.1 misha 1848: **
1849: ** CREATE TABLE t1(c1 VARIANT);
1850: **
1851: ** And the following statement compiled:
1852: **
1.2 misha 1853: ** SELECT c1 + 1, c1 FROM t1;
1.1 misha 1854: **
1855: ** Then this routine would return the string "VARIANT" for the second
1856: ** result column (i==1), and a NULL pointer for the first result column
1857: ** (i==0).
1.2 misha 1858: **
1859: ** SQLite uses dynamic run-time typing. So just because a column
1860: ** is declared to contain a particular type does not mean that the
1861: ** data stored in that column is of the declared type. SQLite is
1862: ** strongly typed, but the typing is dynamic not static. Type
1863: ** is associated with individual values, not with the containers
1864: ** used to hold those values.
1.1 misha 1865: */
1866: const char *sqlite3_column_decltype(sqlite3_stmt *, int i);
1867: const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
1868:
1869: /*
1.2 misha 1870: ** CAPI3REF: Evaluate An SQL Statement
1871: **
1872: ** After an [sqlite3_stmt | SQL statement] has been prepared with a call
1873: ** to either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or to one of
1874: ** the legacy interfaces [sqlite3_prepare()] or [sqlite3_prepare16()],
1875: ** then this function must be called one or more times to evaluate the
1876: ** statement.
1877: **
1878: ** The details of the behavior of this sqlite3_step() interface depend
1879: ** on whether the statement was prepared using the newer "v2" interface
1880: ** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
1881: ** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
1882: ** new "v2" interface is recommended for new applications but the legacy
1883: ** interface will continue to be supported.
1884: **
1885: ** In the lagacy interface, the return value will be either [SQLITE_BUSY],
1886: ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
1887: ** With the "v2" interface, any of the other [SQLITE_OK | result code]
1888: ** or [SQLITE_IOERR_READ | extended result code] might be returned as
1889: ** well.
1890: **
1891: ** [SQLITE_BUSY] means that the database engine was unable to acquire the
1892: ** database locks it needs to do its job. If the statement is a COMMIT
1893: ** or occurs outside of an explicit transaction, then you can retry the
1894: ** statement. If the statement is not a COMMIT and occurs within a
1895: ** explicit transaction then you should rollback the transaction before
1896: ** continuing.
1.1 misha 1897: **
1.2 misha 1898: ** [SQLITE_DONE] means that the statement has finished executing
1.1 misha 1899: ** successfully. sqlite3_step() should not be called again on this virtual
1.2 misha 1900: ** machine without first calling [sqlite3_reset()] to reset the virtual
1901: ** machine back to its initial state.
1.1 misha 1902: **
1903: ** If the SQL statement being executed returns any data, then
1.2 misha 1904: ** [SQLITE_ROW] is returned each time a new row of data is ready
1.1 misha 1905: ** for processing by the caller. The values may be accessed using
1.2 misha 1906: ** the [sqlite3_column_int | column access functions].
1907: ** sqlite3_step() is called again to retrieve the next row of data.
1.1 misha 1908: **
1.2 misha 1909: ** [SQLITE_ERROR] means that a run-time error (such as a constraint
1.1 misha 1910: ** violation) has occurred. sqlite3_step() should not be called again on
1.2 misha 1911: ** the VM. More information may be found by calling [sqlite3_errmsg()].
1912: ** With the legacy interface, a more specific error code (example:
1913: ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
1914: ** can be obtained by calling [sqlite3_reset()] on the
1915: ** [sqlite3_stmt | prepared statement]. In the "v2" interface,
1916: ** the more specific error code is returned directly by sqlite3_step().
1917: **
1918: ** [SQLITE_MISUSE] means that the this routine was called inappropriately.
1919: ** Perhaps it was called on a [sqlite3_stmt | prepared statement] that has
1920: ** already been [sqlite3_finalize | finalized] or on one that had
1921: ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
1922: ** be the case that the same database connection is being used by two or
1923: ** more threads at the same moment in time.
1924: **
1925: ** <b>Goofy Interface Alert:</b>
1926: ** In the legacy interface,
1927: ** the sqlite3_step() API always returns a generic error code,
1928: ** [SQLITE_ERROR], following any error other than [SQLITE_BUSY]
1929: ** and [SQLITE_MISUSE]. You must call [sqlite3_reset()] or
1930: ** [sqlite3_finalize()] in order to find one of the specific
1931: ** [SQLITE_ERROR | result codes] that better describes the error.
1932: ** We admit that this is a goofy design. The problem has been fixed
1933: ** with the "v2" interface. If you prepare all of your SQL statements
1934: ** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
1935: ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()], then the
1936: ** more specific [SQLITE_ERROR | result codes] are returned directly
1937: ** by sqlite3_step(). The use of the "v2" interface is recommended.
1.1 misha 1938: */
1939: int sqlite3_step(sqlite3_stmt*);
1940:
1941: /*
1.2 misha 1942: ** CAPI3REF:
1943: **
1.1 misha 1944: ** Return the number of values in the current row of the result set.
1945: **
1.2 misha 1946: ** After a call to [sqlite3_step()] that returns [SQLITE_ROW], this routine
1947: ** will return the same value as the [sqlite3_column_count()] function.
1948: ** After [sqlite3_step()] has returned an [SQLITE_DONE], [SQLITE_BUSY], or
1949: ** a [SQLITE_ERROR | error code], or before [sqlite3_step()] has been
1950: ** called on the [sqlite3_stmt | prepared statement] for the first time,
1951: ** this routine returns zero.
1.1 misha 1952: */
1953: int sqlite3_data_count(sqlite3_stmt *pStmt);
1954:
1955: /*
1.2 misha 1956: ** CAPI3REF: Fundamental Datatypes
1957: **
1958: ** Every value in SQLite has one of five fundamental datatypes:
1959: **
1960: ** <ul>
1961: ** <li> 64-bit signed integer
1962: ** <li> 64-bit IEEE floating point number
1963: ** <li> string
1964: ** <li> BLOB
1965: ** <li> NULL
1966: ** </ul>
1967: **
1968: ** These constants are codes for each of those types.
1969: **
1970: ** Note that the SQLITE_TEXT constant was also used in SQLite version 2
1971: ** for a completely different meaning. Software that links against both
1972: ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT not
1973: ** SQLITE_TEXT.
1.1 misha 1974: */
1975: #define SQLITE_INTEGER 1
1976: #define SQLITE_FLOAT 2
1977: #define SQLITE_BLOB 4
1978: #define SQLITE_NULL 5
1979: #ifdef SQLITE_TEXT
1980: # undef SQLITE_TEXT
1981: #else
1982: # define SQLITE_TEXT 3
1983: #endif
1984: #define SQLITE3_TEXT 3
1985:
1986: /*
1.2 misha 1987: ** CAPI3REF: Results Values From A Query
1988: **
1989: ** These routines return information about
1990: ** a single column of the current result row of a query. In every
1991: ** case the first argument is a pointer to the
1992: ** [sqlite3_stmt | SQL statement] that is being
1993: ** evaluated (the [sqlite3_stmt*] that was returned from
1994: ** [sqlite3_prepare_v2()] or one of its variants) and
1.1 misha 1995: ** the second argument is the index of the column for which information
1.2 misha 1996: ** should be returned. The left-most column of the result set
1997: ** has an index of 0.
1.1 misha 1998: **
1999: ** If the SQL statement is not currently point to a valid row, or if the
1.2 misha 2000: ** the column index is out of range, the result is undefined.
2001: ** These routines may only be called when the most recent call to
2002: ** [sqlite3_step()] has returned [SQLITE_ROW] and neither
2003: ** [sqlite3_reset()] nor [sqlite3_finalize()] has been call subsequently.
2004: ** If any of these routines are called after [sqlite3_reset()] or
2005: ** [sqlite3_finalize()] or after [sqlite3_step()] has returned
2006: ** something other than [SQLITE_ROW], the results are undefined.
2007: ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
2008: ** are called from a different thread while any of these routines
2009: ** are pending, then the results are undefined.
2010: **
2011: ** The sqlite3_column_type() routine returns
2012: ** [SQLITE_INTEGER | datatype code] for the initial data type
2013: ** of the result column. The returned value is one of [SQLITE_INTEGER],
2014: ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value
2015: ** returned by sqlite3_column_type() is only meaningful if no type
2016: ** conversions have occurred as described below. After a type conversion,
2017: ** the value returned by sqlite3_column_type() is undefined. Future
2018: ** versions of SQLite may change the behavior of sqlite3_column_type()
2019: ** following a type conversion.
2020: **
2021: ** If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
2022: ** routine returns the number of bytes in that BLOB or string.
2023: ** If the result is a UTF-16 string, then sqlite3_column_bytes() converts
2024: ** the string to UTF-8 and then returns the number of bytes.
2025: ** If the result is a numeric value then sqlite3_column_bytes() uses
2026: ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
2027: ** the number of bytes in that string.
2028: ** The value returned does not include the zero terminator at the end
2029: ** of the string. For clarity: the value returned is the number of
2030: ** bytes in the string, not the number of characters.
2031: **
2032: ** Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
2033: ** even zero-length strings, are always zero terminated. The return
2034: ** value from sqlite3_column_blob() for a zero-length blob is an arbitrary
2035: ** pointer, possibly even a NULL pointer.
2036: **
2037: ** The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes()
2038: ** but leaves the result in UTF-16 instead of UTF-8.
2039: ** The zero terminator is not included in this count.
1.1 misha 2040: **
2041: ** These routines attempt to convert the value where appropriate. For
2042: ** example, if the internal representation is FLOAT and a text result
1.2 misha 2043: ** is requested, [sqlite3_snprintf()] is used internally to do the conversion
1.1 misha 2044: ** automatically. The following table details the conversions that
2045: ** are applied:
2046: **
1.2 misha 2047: ** <blockquote>
2048: ** <table border="1">
2049: ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
2050: **
2051: ** <tr><td> NULL <td> INTEGER <td> Result is 0
2052: ** <tr><td> NULL <td> FLOAT <td> Result is 0.0
2053: ** <tr><td> NULL <td> TEXT <td> Result is NULL pointer
2054: ** <tr><td> NULL <td> BLOB <td> Result is NULL pointer
2055: ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
2056: ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
2057: ** <tr><td> INTEGER <td> BLOB <td> Same as for INTEGER->TEXT
2058: ** <tr><td> FLOAT <td> INTEGER <td> Convert from float to integer
2059: ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
2060: ** <tr><td> FLOAT <td> BLOB <td> Same as FLOAT->TEXT
2061: ** <tr><td> TEXT <td> INTEGER <td> Use atoi()
2062: ** <tr><td> TEXT <td> FLOAT <td> Use atof()
2063: ** <tr><td> TEXT <td> BLOB <td> No change
2064: ** <tr><td> BLOB <td> INTEGER <td> Convert to TEXT then use atoi()
2065: ** <tr><td> BLOB <td> FLOAT <td> Convert to TEXT then use atof()
2066: ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
2067: ** </table>
2068: ** </blockquote>
2069: **
2070: ** The table above makes reference to standard C library functions atoi()
2071: ** and atof(). SQLite does not really use these functions. It has its
2072: ** on equavalent internal routines. The atoi() and atof() names are
2073: ** used in the table for brevity and because they are familiar to most
2074: ** C programmers.
2075: **
2076: ** Note that when type conversions occur, pointers returned by prior
2077: ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
2078: ** sqlite3_column_text16() may be invalidated.
2079: ** Type conversions and pointer invalidations might occur
2080: ** in the following cases:
2081: **
2082: ** <ul>
2083: ** <li><p> The initial content is a BLOB and sqlite3_column_text()
2084: ** or sqlite3_column_text16() is called. A zero-terminator might
2085: ** need to be added to the string.</p></li>
2086: **
2087: ** <li><p> The initial content is UTF-8 text and sqlite3_column_bytes16() or
2088: ** sqlite3_column_text16() is called. The content must be converted
2089: ** to UTF-16.</p></li>
2090: **
2091: ** <li><p> The initial content is UTF-16 text and sqlite3_column_bytes() or
2092: ** sqlite3_column_text() is called. The content must be converted
2093: ** to UTF-8.</p></li>
2094: ** </ul>
2095: **
2096: ** Conversions between UTF-16be and UTF-16le are always done in place and do
2097: ** not invalidate a prior pointer, though of course the content of the buffer
2098: ** that the prior pointer points to will have been modified. Other kinds
2099: ** of conversion are done in place when it is possible, but sometime it is
2100: ** not possible and in those cases prior pointers are invalidated.
2101: **
2102: ** The safest and easiest to remember policy is to invoke these routines
2103: ** in one of the following ways:
2104: **
2105: ** <ul>
2106: ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
2107: ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
2108: ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
2109: ** </ul>
2110: **
2111: ** In other words, you should call sqlite3_column_text(), sqlite3_column_blob(),
2112: ** or sqlite3_column_text16() first to force the result into the desired
2113: ** format, then invoke sqlite3_column_bytes() or sqlite3_column_bytes16() to
2114: ** find the size of the result. Do not mix call to sqlite3_column_text() or
2115: ** sqlite3_column_blob() with calls to sqlite3_column_bytes16(). And do not
2116: ** mix calls to sqlite3_column_text16() with calls to sqlite3_column_bytes().
2117: **
2118: ** The pointers returned are valid until a type conversion occurs as
2119: ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
2120: ** [sqlite3_finalize()] is called. The memory space used to hold strings
2121: ** and blobs is freed automatically. Do <b>not</b> pass the pointers returned
2122: ** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
2123: ** [sqlite3_free()].
2124: **
2125: ** If a memory allocation error occurs during the evaluation of any
2126: ** of these routines, a default value is returned. The default value
2127: ** is either the integer 0, the floating point number 0.0, or a NULL
2128: ** pointer. Subsequent calls to [sqlite3_errcode()] will return
2129: ** [SQLITE_NOMEM].
1.1 misha 2130: */
2131: const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
2132: int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
2133: int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
2134: double sqlite3_column_double(sqlite3_stmt*, int iCol);
2135: int sqlite3_column_int(sqlite3_stmt*, int iCol);
1.2 misha 2136: sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
1.1 misha 2137: const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
2138: const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
2139: int sqlite3_column_type(sqlite3_stmt*, int iCol);
1.2 misha 2140: sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
1.1 misha 2141:
2142: /*
1.2 misha 2143: ** CAPI3REF: Destroy A Prepared Statement Object
2144: **
2145: ** The sqlite3_finalize() function is called to delete a
2146: ** [sqlite3_stmt | compiled SQL statement]. If the statement was
2147: ** executed successfully, or not executed at all, then SQLITE_OK is returned.
2148: ** If execution of the statement failed then an
2149: ** [SQLITE_ERROR | error code] or [SQLITE_IOERR_READ | extended error code]
2150: ** is returned.
1.1 misha 2151: **
2152: ** This routine can be called at any point during the execution of the
1.2 misha 2153: ** [sqlite3_stmt | virtual machine]. If the virtual machine has not
2154: ** completed execution when this routine is called, that is like
2155: ** encountering an error or an interrupt. (See [sqlite3_interrupt()].)
2156: ** Incomplete updates may be rolled back and transactions cancelled,
2157: ** depending on the circumstances, and the
2158: ** [SQLITE_ERROR | result code] returned will be [SQLITE_ABORT].
1.1 misha 2159: */
2160: int sqlite3_finalize(sqlite3_stmt *pStmt);
2161:
2162: /*
1.2 misha 2163: ** CAPI3REF: Reset A Prepared Statement Object
2164: **
2165: ** The sqlite3_reset() function is called to reset a
2166: ** [sqlite3_stmt | compiled SQL statement] object.
2167: ** back to it's initial state, ready to be re-executed.
1.1 misha 2168: ** Any SQL statement variables that had values bound to them using
1.2 misha 2169: ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
2170: ** Use [sqlite3_clear_bindings()] to reset the bindings.
1.1 misha 2171: */
2172: int sqlite3_reset(sqlite3_stmt *pStmt);
2173:
2174: /*
1.2 misha 2175: ** CAPI3REF: Create Or Redefine SQL Functions
2176: **
2177: ** The following two functions are used to add SQL functions or aggregates
2178: ** or to redefine the behavior of existing SQL functions or aggregates. The
1.1 misha 2179: ** difference only between the two is that the second parameter, the
2180: ** name of the (scalar) function or aggregate, is encoded in UTF-8 for
2181: ** sqlite3_create_function() and UTF-16 for sqlite3_create_function16().
2182: **
1.2 misha 2183: ** The first argument is the [sqlite3 | database handle] that holds the
2184: ** SQL function or aggregate is to be added or redefined. If a single
2185: ** program uses more than one database handle internally, then SQL
2186: ** functions or aggregates must be added individually to each database
2187: ** handle with which they will be used.
2188: **
2189: ** The second parameter is the name of the SQL function to be created
2190: ** or redefined.
2191: ** The length of the name is limited to 255 bytes, exclusive of the
2192: ** zero-terminator. Note that the name length limit is in bytes, not
2193: ** characters. Any attempt to create a function with a longer name
2194: ** will result in an SQLITE_ERROR error.
1.1 misha 2195: **
1.2 misha 2196: ** The third parameter is the number of arguments that the SQL function or
2197: ** aggregate takes. If this parameter is negative, then the SQL function or
1.1 misha 2198: ** aggregate may take any number of arguments.
2199: **
1.2 misha 2200: ** The fourth parameter, eTextRep, specifies what
2201: ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
2202: ** its parameters. Any SQL function implementation should be able to work
2203: ** work with UTF-8, UTF-16le, or UTF-16be. But some implementations may be
2204: ** more efficient with one encoding than another. It is allowed to
2205: ** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
2206: ** times with the same function but with different values of eTextRep.
2207: ** When multiple implementations of the same function are available, SQLite
2208: ** will pick the one that involves the least amount of data conversion.
2209: ** If there is only a single implementation which does not care what
2210: ** text encoding is used, then the fourth argument should be
2211: ** [SQLITE_ANY].
2212: **
2213: ** The fifth parameter is an arbitrary pointer. The implementation
2214: ** of the function can gain access to this pointer using
2215: ** [sqlite3_user_data()].
1.1 misha 2216: **
2217: ** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
1.2 misha 2218: ** pointers to C-language functions that implement the SQL
2219: ** function or aggregate. A scalar SQL function requires an implementation of
1.1 misha 2220: ** the xFunc callback only, NULL pointers should be passed as the xStep
1.2 misha 2221: ** and xFinal parameters. An aggregate SQL function requires an implementation
2222: ** of xStep and xFinal and NULL should be passed for xFunc. To delete an
2223: ** existing SQL function or aggregate, pass NULL for all three function
2224: ** callback.
2225: **
2226: ** It is permitted to register multiple implementations of the same
2227: ** functions with the same name but with either differing numbers of
2228: ** arguments or differing perferred text encodings. SQLite will use
2229: ** the implementation most closely matches the way in which the
2230: ** SQL function is used.
1.1 misha 2231: */
2232: int sqlite3_create_function(
2233: sqlite3 *,
2234: const char *zFunctionName,
2235: int nArg,
2236: int eTextRep,
2237: void*,
2238: void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
2239: void (*xStep)(sqlite3_context*,int,sqlite3_value**),
2240: void (*xFinal)(sqlite3_context*)
2241: );
2242: int sqlite3_create_function16(
2243: sqlite3*,
2244: const void *zFunctionName,
2245: int nArg,
2246: int eTextRep,
2247: void*,
2248: void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
2249: void (*xStep)(sqlite3_context*,int,sqlite3_value**),
2250: void (*xFinal)(sqlite3_context*)
2251: );
2252:
2253: /*
1.2 misha 2254: ** CAPI3REF: Text Encodings
2255: **
2256: ** These constant define integer codes that represent the various
2257: ** text encodings supported by SQLite.
2258: */
2259: #define SQLITE_UTF8 1
2260: #define SQLITE_UTF16LE 2
2261: #define SQLITE_UTF16BE 3
2262: #define SQLITE_UTF16 4 /* Use native byte order */
2263: #define SQLITE_ANY 5 /* sqlite3_create_function only */
2264: #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
2265:
2266: /*
2267: ** CAPI3REF: Obsolete Functions
2268: **
2269: ** These functions are all now obsolete. In order to maintain
2270: ** backwards compatibility with older code, we continue to support
2271: ** these functions. However, new development projects should avoid
2272: ** the use of these functions. To help encourage people to avoid
2273: ** using these functions, we are not going to tell you want they do.
1.1 misha 2274: */
2275: int sqlite3_aggregate_count(sqlite3_context*);
1.2 misha 2276: int sqlite3_expired(sqlite3_stmt*);
2277: int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
2278: int sqlite3_global_recover(void);
2279: void sqlite3_thread_cleanup(void);
1.3 ! misha 2280: int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
1.2 misha 2281:
2282: /*
2283: ** CAPI3REF: Obtaining SQL Function Parameter Values
2284: **
2285: ** The C-language implementation of SQL functions and aggregates uses
2286: ** this set of interface routines to access the parameter values on
2287: ** the function or aggregate.
2288: **
2289: ** The xFunc (for scalar functions) or xStep (for aggregates) parameters
2290: ** to [sqlite3_create_function()] and [sqlite3_create_function16()]
2291: ** define callbacks that implement the SQL functions and aggregates.
2292: ** The 4th parameter to these callbacks is an array of pointers to
2293: ** [sqlite3_value] objects. There is one [sqlite3_value] object for
2294: ** each parameter to the SQL function. These routines are used to
2295: ** extract values from the [sqlite3_value] objects.
2296: **
2297: ** These routines work just like the corresponding
2298: ** [sqlite3_column_blob | sqlite3_column_* routines] except that
2299: ** these routines take a single [sqlite3_value*] pointer instead
2300: ** of an [sqlite3_stmt*] pointer and an integer column number.
2301: **
2302: ** The sqlite3_value_text16() interface extracts a UTF16 string
2303: ** in the native byte-order of the host machine. The
2304: ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
2305: ** extract UTF16 strings as big-endian and little-endian respectively.
2306: **
2307: ** The sqlite3_value_numeric_type() interface attempts to apply
2308: ** numeric affinity to the value. This means that an attempt is
2309: ** made to convert the value to an integer or floating point. If
2310: ** such a conversion is possible without loss of information (in order
2311: ** words if the value is original a string that looks like a number)
2312: ** then it is done. Otherwise no conversion occurs. The
2313: ** [SQLITE_INTEGER | datatype] after conversion is returned.
2314: **
2315: ** Please pay particular attention to the fact that the pointer that
2316: ** is returned from [sqlite3_value_blob()], [sqlite3_value_text()], or
2317: ** [sqlite3_value_text16()] can be invalidated by a subsequent call to
2318: ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
2319: ** or [sqlite3_value_text16()].
2320: **
2321: ** These routines must be called from the same thread as
2322: ** the SQL function that supplied the sqlite3_value* parameters.
2323: ** Or, if the sqlite3_value* argument comes from the [sqlite3_column_value()]
2324: ** interface, then these routines should be called from the same thread
2325: ** that ran [sqlite3_column_value()].
1.1 misha 2326: */
2327: const void *sqlite3_value_blob(sqlite3_value*);
2328: int sqlite3_value_bytes(sqlite3_value*);
2329: int sqlite3_value_bytes16(sqlite3_value*);
2330: double sqlite3_value_double(sqlite3_value*);
2331: int sqlite3_value_int(sqlite3_value*);
1.2 misha 2332: sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
1.1 misha 2333: const unsigned char *sqlite3_value_text(sqlite3_value*);
2334: const void *sqlite3_value_text16(sqlite3_value*);
2335: const void *sqlite3_value_text16le(sqlite3_value*);
2336: const void *sqlite3_value_text16be(sqlite3_value*);
2337: int sqlite3_value_type(sqlite3_value*);
1.2 misha 2338: int sqlite3_value_numeric_type(sqlite3_value*);
1.1 misha 2339:
2340: /*
1.2 misha 2341: ** CAPI3REF: Obtain Aggregate Function Context
2342: **
2343: ** The implementation of aggregate SQL functions use this routine to allocate
1.1 misha 2344: ** a structure for storing their state. The first time this routine
2345: ** is called for a particular aggregate, a new structure of size nBytes
2346: ** is allocated, zeroed, and returned. On subsequent calls (for the
2347: ** same aggregate instance) the same buffer is returned. The implementation
2348: ** of the aggregate can use the returned buffer to accumulate data.
2349: **
1.2 misha 2350: ** The buffer allocated is freed automatically by SQLite whan the aggregate
2351: ** query concludes.
2352: **
2353: ** The first parameter should be a copy of the
2354: ** [sqlite3_context | SQL function context] that is the first
2355: ** parameter to the callback routine that implements the aggregate
2356: ** function.
2357: **
2358: ** This routine must be called from the same thread in which
2359: ** the aggregate SQL function is running.
1.1 misha 2360: */
2361: void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
2362:
2363: /*
1.2 misha 2364: ** CAPI3REF: User Data For Functions
2365: **
2366: ** The pUserData parameter to the [sqlite3_create_function()]
2367: ** and [sqlite3_create_function16()] routines
2368: ** used to register user functions is available to
2369: ** the implementation of the function using this call.
2370: **
2371: ** This routine must be called from the same thread in which
2372: ** the SQL function is running.
1.1 misha 2373: */
2374: void *sqlite3_user_data(sqlite3_context*);
2375:
2376: /*
1.2 misha 2377: ** CAPI3REF: Function Auxiliary Data
2378: **
2379: ** The following two functions may be used by scalar SQL functions to
1.1 misha 2380: ** associate meta-data with argument values. If the same value is passed to
1.2 misha 2381: ** multiple invocations of the same SQL function during query execution, under
1.1 misha 2382: ** some circumstances the associated meta-data may be preserved. This may
2383: ** be used, for example, to add a regular-expression matching scalar
2384: ** function. The compiled version of the regular expression is stored as
2385: ** meta-data associated with the SQL value passed as the regular expression
1.2 misha 2386: ** pattern. The compiled regular expression can be reused on multiple
2387: ** invocations of the same function so that the original pattern string
2388: ** does not need to be recompiled on each invocation.
1.1 misha 2389: **
1.2 misha 2390: ** The sqlite3_get_auxdata() interface returns a pointer to the meta-data
2391: ** associated with the Nth argument value to the current SQL function
1.1 misha 2392: ** call, where N is the second parameter. If no meta-data has been set for
2393: ** that value, then a NULL pointer is returned.
2394: **
1.2 misha 2395: ** The sqlite3_set_auxdata() is used to associate meta-data with an SQL
2396: ** function argument. The third parameter is a pointer to the meta-data
1.1 misha 2397: ** to be associated with the Nth user function argument value. The fourth
1.2 misha 2398: ** parameter specifies a destructor that will be called on the meta-
2399: ** data pointer to release it when it is no longer required. If the
2400: ** destructor is NULL, it is not invoked.
1.1 misha 2401: **
2402: ** In practice, meta-data is preserved between function calls for
2403: ** expressions that are constant at compile time. This includes literal
2404: ** values and SQL variables.
1.2 misha 2405: **
2406: ** These routines must be called from the same thread in which
2407: ** the SQL function is running.
1.1 misha 2408: */
2409: void *sqlite3_get_auxdata(sqlite3_context*, int);
2410: void sqlite3_set_auxdata(sqlite3_context*, int, void*, void (*)(void*));
2411:
2412:
2413: /*
1.2 misha 2414: ** CAPI3REF: Constants Defining Special Destructor Behavior
2415: **
1.1 misha 2416: ** These are special value for the destructor that is passed in as the
1.2 misha 2417: ** final argument to routines like [sqlite3_result_blob()]. If the destructor
1.1 misha 2418: ** argument is SQLITE_STATIC, it means that the content pointer is constant
2419: ** and will never change. It does not need to be destroyed. The
2420: ** SQLITE_TRANSIENT value means that the content will likely change in
2421: ** the near future and that SQLite should make its own private copy of
2422: ** the content before returning.
1.2 misha 2423: **
2424: ** The typedef is necessary to work around problems in certain
2425: ** C++ compilers. See ticket #2191.
1.1 misha 2426: */
1.2 misha 2427: typedef void (*sqlite3_destructor_type)(void*);
2428: #define SQLITE_STATIC ((sqlite3_destructor_type)0)
2429: #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
2430:
2431: /*
2432: ** CAPI3REF: Setting The Result Of An SQL Function
2433: **
2434: ** These routines are used by the xFunc or xFinal callbacks that
2435: ** implement SQL functions and aggregates. See
2436: ** [sqlite3_create_function()] and [sqlite3_create_function16()]
2437: ** for additional information.
2438: **
2439: ** These functions work very much like the
2440: ** [sqlite3_bind_blob | sqlite3_bind_*] family of functions used
2441: ** to bind values to host parameters in prepared statements.
2442: ** Refer to the
2443: ** [sqlite3_bind_blob | sqlite3_bind_* documentation] for
2444: ** additional information.
2445: **
2446: ** The sqlite3_result_error() and sqlite3_result_error16() functions
2447: ** cause the implemented SQL function to throw an exception. The
2448: ** parameter to sqlite3_result_error() or sqlite3_result_error16()
2449: ** is the text of an error message.
2450: **
2451: ** The sqlite3_result_toobig() cause the function implementation
2452: ** to throw and error indicating that a string or BLOB is to long
2453: ** to represent.
2454: **
2455: ** These routines must be called from within the same thread as
2456: ** the SQL function associated with the [sqlite3_context] pointer.
1.1 misha 2457: */
2458: void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
2459: void sqlite3_result_double(sqlite3_context*, double);
2460: void sqlite3_result_error(sqlite3_context*, const char*, int);
2461: void sqlite3_result_error16(sqlite3_context*, const void*, int);
1.2 misha 2462: void sqlite3_result_error_toobig(sqlite3_context*);
2463: void sqlite3_result_error_nomem(sqlite3_context*);
1.1 misha 2464: void sqlite3_result_int(sqlite3_context*, int);
1.2 misha 2465: void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
1.1 misha 2466: void sqlite3_result_null(sqlite3_context*);
2467: void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
2468: void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
2469: void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
2470: void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
2471: void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
1.2 misha 2472: void sqlite3_result_zeroblob(sqlite3_context*, int n);
1.1 misha 2473:
2474: /*
1.2 misha 2475: ** CAPI3REF: Define New Collating Sequences
2476: **
2477: ** These functions are used to add new collation sequences to the
2478: ** [sqlite3*] handle specified as the first argument.
1.1 misha 2479: **
2480: ** The name of the new collation sequence is specified as a UTF-8 string
1.2 misha 2481: ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
2482: ** and a UTF-16 string for sqlite3_create_collation16(). In all cases
2483: ** the name is passed as the second function argument.
1.1 misha 2484: **
1.3 ! misha 2485: ** The third argument may be one of the constants [SQLITE_UTF8],
1.2 misha 2486: ** [SQLITE_UTF16LE] or [SQLITE_UTF16BE], indicating that the user-supplied
1.1 misha 2487: ** routine expects to be passed pointers to strings encoded using UTF-8,
1.3 ! misha 2488: ** UTF-16 little-endian or UTF-16 big-endian respectively. The
! 2489: ** third argument might also be [SQLITE_UTF16_ALIGNED] to indicate that
! 2490: ** the routine expects pointers to 16-bit word aligned strings
! 2491: ** of UTF16 in the native byte order of the host computer.
1.1 misha 2492: **
2493: ** A pointer to the user supplied routine must be passed as the fifth
2494: ** argument. If it is NULL, this is the same as deleting the collation
2495: ** sequence (so that SQLite cannot call it anymore). Each time the user
2496: ** supplied function is invoked, it is passed a copy of the void* passed as
2497: ** the fourth argument to sqlite3_create_collation() or
2498: ** sqlite3_create_collation16() as its first parameter.
2499: **
2500: ** The remaining arguments to the user-supplied routine are two strings,
2501: ** each represented by a [length, data] pair and encoded in the encoding
2502: ** that was passed as the third argument when the collation sequence was
2503: ** registered. The user routine should return negative, zero or positive if
2504: ** the first string is less than, equal to, or greater than the second
2505: ** string. i.e. (STRING1 - STRING2).
1.2 misha 2506: **
2507: ** The sqlite3_create_collation_v2() works like sqlite3_create_collation()
2508: ** excapt that it takes an extra argument which is a destructor for
2509: ** the collation. The destructor is called when the collation is
2510: ** destroyed and is passed a copy of the fourth parameter void* pointer
2511: ** of the sqlite3_create_collation_v2(). Collations are destroyed when
2512: ** they are overridden by later calls to the collation creation functions
2513: ** or when the [sqlite3*] database handle is closed using [sqlite3_close()].
2514: **
2515: ** The sqlite3_create_collation_v2() interface is experimental and
2516: ** subject to change in future releases. The other collation creation
2517: ** functions are stable.
1.1 misha 2518: */
2519: int sqlite3_create_collation(
2520: sqlite3*,
2521: const char *zName,
2522: int eTextRep,
2523: void*,
2524: int(*xCompare)(void*,int,const void*,int,const void*)
2525: );
1.2 misha 2526: int sqlite3_create_collation_v2(
2527: sqlite3*,
2528: const char *zName,
2529: int eTextRep,
2530: void*,
2531: int(*xCompare)(void*,int,const void*,int,const void*),
2532: void(*xDestroy)(void*)
2533: );
1.1 misha 2534: int sqlite3_create_collation16(
2535: sqlite3*,
2536: const char *zName,
2537: int eTextRep,
2538: void*,
2539: int(*xCompare)(void*,int,const void*,int,const void*)
2540: );
2541:
2542: /*
1.2 misha 2543: ** CAPI3REF: Collation Needed Callbacks
2544: **
1.1 misha 2545: ** To avoid having to register all collation sequences before a database
2546: ** can be used, a single callback function may be registered with the
2547: ** database handle to be called whenever an undefined collation sequence is
2548: ** required.
2549: **
2550: ** If the function is registered using the sqlite3_collation_needed() API,
2551: ** then it is passed the names of undefined collation sequences as strings
2552: ** encoded in UTF-8. If sqlite3_collation_needed16() is used, the names
2553: ** are passed as UTF-16 in machine native byte order. A call to either
2554: ** function replaces any existing callback.
2555: **
1.2 misha 2556: ** When the callback is invoked, the first argument passed is a copy
1.1 misha 2557: ** of the second argument to sqlite3_collation_needed() or
2558: ** sqlite3_collation_needed16(). The second argument is the database
1.2 misha 2559: ** handle. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], or
2560: ** [SQLITE_UTF16LE], indicating the most desirable form of the collation
1.1 misha 2561: ** sequence function required. The fourth parameter is the name of the
2562: ** required collation sequence.
2563: **
1.2 misha 2564: ** The callback function should register the desired collation using
2565: ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
2566: ** [sqlite3_create_collation_v2()].
1.1 misha 2567: */
2568: int sqlite3_collation_needed(
2569: sqlite3*,
2570: void*,
2571: void(*)(void*,sqlite3*,int eTextRep,const char*)
2572: );
2573: int sqlite3_collation_needed16(
2574: sqlite3*,
2575: void*,
2576: void(*)(void*,sqlite3*,int eTextRep,const void*)
2577: );
2578:
2579: /*
2580: ** Specify the key for an encrypted database. This routine should be
2581: ** called right after sqlite3_open().
2582: **
2583: ** The code to implement this API is not available in the public release
2584: ** of SQLite.
2585: */
2586: int sqlite3_key(
2587: sqlite3 *db, /* Database to be rekeyed */
2588: const void *pKey, int nKey /* The key */
2589: );
2590:
2591: /*
2592: ** Change the key on an open database. If the current database is not
2593: ** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
2594: ** database is decrypted.
2595: **
2596: ** The code to implement this API is not available in the public release
2597: ** of SQLite.
2598: */
2599: int sqlite3_rekey(
2600: sqlite3 *db, /* Database to be rekeyed */
2601: const void *pKey, int nKey /* The new key */
2602: );
2603:
2604: /*
1.2 misha 2605: ** CAPI3REF: Suspend Execution For A Short Time
2606: **
2607: ** This function causes the current thread to suspend execution
2608: ** a number of milliseconds specified in its parameter.
2609: **
2610: ** If the operating system does not support sleep requests with
2611: ** millisecond time resolution, then the time will be rounded up to
2612: ** the nearest second. The number of milliseconds of sleep actually
2613: ** requested from the operating system is returned.
2614: **
2615: ** SQLite implements this interface by calling the xSleep()
2616: ** method of the default [sqlite3_vfs] object.
2617: */
2618: int sqlite3_sleep(int);
2619:
2620: /*
2621: ** CAPI3REF: Name Of The Folder Holding Temporary Files
2622: **
2623: ** If this global variable is made to point to a string which is
2624: ** the name of a folder (a.ka. directory), then all temporary files
1.1 misha 2625: ** created by SQLite will be placed in that directory. If this variable
2626: ** is NULL pointer, then SQLite does a search for an appropriate temporary
2627: ** file directory.
2628: **
1.2 misha 2629: ** It is not safe to modify this variable once a database connection
2630: ** has been opened. It is intended that this variable be set once
2631: ** as part of process initialization and before any SQLite interface
2632: ** routines have been call and remain unchanged thereafter.
2633: */
2634: SQLITE_EXTERN char *sqlite3_temp_directory;
2635:
2636: /*
2637: ** CAPI3REF: Test To See If The Database Is In Auto-Commit Mode
2638: **
2639: ** Test to see whether or not the database connection is in autocommit
2640: ** mode. Return TRUE if it is and FALSE if not. Autocommit mode is on
2641: ** by default. Autocommit is disabled by a BEGIN statement and reenabled
2642: ** by the next COMMIT or ROLLBACK.
2643: **
2644: ** If certain kinds of errors occur on a statement within a multi-statement
2645: ** transactions (errors including [SQLITE_FULL], [SQLITE_IOERR],
2646: ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
2647: ** transaction might be rolled back automatically. The only way to
2648: ** find out if SQLite automatically rolled back the transaction after
2649: ** an error is to use this function.
2650: **
2651: ** If another thread changes the autocommit status of the database
2652: ** connection while this routine is running, then the return value
2653: ** is undefined.
2654: */
2655: int sqlite3_get_autocommit(sqlite3*);
2656:
2657: /*
2658: ** CAPI3REF: Find The Database Handle Associated With A Prepared Statement
2659: **
2660: ** Return the [sqlite3*] database handle to which a
2661: ** [sqlite3_stmt | prepared statement] belongs.
2662: ** This is the same database handle that was
2663: ** the first argument to the [sqlite3_prepare_v2()] or its variants
2664: ** that was used to create the statement in the first place.
2665: */
2666: sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
2667:
2668:
2669: /*
2670: ** CAPI3REF: Commit And Rollback Notification Callbacks
2671: **
2672: ** These routines
2673: ** register callback functions to be invoked whenever a transaction
2674: ** is committed or rolled back. The pArg argument is passed through
2675: ** to the callback. If the callback on a commit hook function
2676: ** returns non-zero, then the commit is converted into a rollback.
2677: **
2678: ** If another function was previously registered, its pArg value is returned.
2679: ** Otherwise NULL is returned.
2680: **
2681: ** Registering a NULL function disables the callback.
2682: **
2683: ** For the purposes of this API, a transaction is said to have been
2684: ** rolled back if an explicit "ROLLBACK" statement is executed, or
2685: ** an error or constraint causes an implicit rollback to occur. The
2686: ** callback is not invoked if a transaction is automatically rolled
2687: ** back because the database connection is closed.
2688: **
2689: ** These are experimental interfaces and are subject to change.
2690: */
2691: void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
2692: void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
2693:
2694: /*
2695: ** CAPI3REF: Data Change Notification Callbacks
2696: **
2697: ** Register a callback function with the database connection identified by the
2698: ** first argument to be invoked whenever a row is updated, inserted or deleted.
2699: ** Any callback set by a previous call to this function for the same
2700: ** database connection is overridden.
2701: **
2702: ** The second argument is a pointer to the function to invoke when a
2703: ** row is updated, inserted or deleted. The first argument to the callback is
2704: ** a copy of the third argument to sqlite3_update_hook(). The second callback
2705: ** argument is one of SQLITE_INSERT, SQLITE_DELETE or SQLITE_UPDATE, depending
2706: ** on the operation that caused the callback to be invoked. The third and
2707: ** fourth arguments to the callback contain pointers to the database and
2708: ** table name containing the affected row. The final callback parameter is
2709: ** the rowid of the row. In the case of an update, this is the rowid after
2710: ** the update takes place.
2711: **
2712: ** The update hook is not invoked when internal system tables are
2713: ** modified (i.e. sqlite_master and sqlite_sequence).
2714: **
2715: ** If another function was previously registered, its pArg value is returned.
2716: ** Otherwise NULL is returned.
2717: */
2718: void *sqlite3_update_hook(
2719: sqlite3*,
2720: void(*)(void *,int ,char const *,char const *,sqlite3_int64),
2721: void*
2722: );
2723:
2724: /*
2725: ** CAPI3REF: Enable Or Disable Shared Pager Cache
2726: **
2727: ** This routine enables or disables the sharing of the database cache
2728: ** and schema data structures between connections to the same database.
2729: ** Sharing is enabled if the argument is true and disabled if the argument
2730: ** is false.
2731: **
2732: ** Beginning in SQLite version 3.5.0, cache sharing is enabled and disabled
2733: ** for an entire process. In prior versions of SQLite, sharing was
2734: ** enabled or disabled for each thread separately.
2735: **
2736: ** The cache sharing mode set by this interface effects all subsequent
2737: ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
2738: ** Existing database connections continue use the sharing mode that was
2739: ** in effect at the time they were opened.
2740: **
2741: ** Virtual tables cannot be used with a shared cache. When shared
2742: ** cache is enabled, the [sqlite3_create_module()] API used to register
2743: ** virtual tables will always return an error.
2744: **
2745: ** This routine returns [SQLITE_OK] if shared cache was
2746: ** enabled or disabled successfully. An [SQLITE_ERROR | error code]
2747: ** is returned otherwise.
2748: **
2749: ** Shared cache is disabled by default. But this might change in
2750: ** future releases of SQLite. Applications that care about shared
2751: ** cache setting should set it explicitly.
2752: */
2753: int sqlite3_enable_shared_cache(int);
2754:
2755: /*
2756: ** CAPI3REF: Attempt To Free Heap Memory
2757: **
2758: ** Attempt to free N bytes of heap memory by deallocating non-essential
2759: ** memory allocations held by the database library (example: memory
2760: ** used to cache database pages to improve performance).
2761: */
2762: int sqlite3_release_memory(int);
2763:
2764: /*
2765: ** CAPI3REF: Impose A Limit On Heap Size
2766: **
2767: ** Place a "soft" limit on the amount of heap memory that may be allocated
2768: ** by SQLite. If an internal allocation is requested
2769: ** that would exceed the specified limit, [sqlite3_release_memory()] is
2770: ** invoked one or more times to free up some space before the allocation
2771: ** is made.
2772: **
2773: ** The limit is called "soft", because if [sqlite3_release_memory()] cannot
2774: ** free sufficient memory to prevent the limit from being exceeded,
2775: ** the memory is allocated anyway and the current operation proceeds.
2776: **
2777: ** A negative or zero value for N means that there is no soft heap limit and
2778: ** [sqlite3_release_memory()] will only be called when memory is exhausted.
2779: ** The default value for the soft heap limit is zero.
2780: **
2781: ** SQLite makes a best effort to honor the soft heap limit. But if it
2782: ** is unable to reduce memory usage below the soft limit, execution will
2783: ** continue without error or notification. This is why the limit is
2784: ** called a "soft" limit. It is advisory only.
2785: **
2786: ** Prior to SQLite version 3.5.0, this routine only constrained the memory
2787: ** allocated by a single thread - the same thread in which this routine
2788: ** runs. Beginning with SQLite version 3.5.0, the soft heap limit is
2789: ** applied to all threads. The value specified for the soft heap limit
2790: ** is an upper bound on the total memory allocation for all threads. In
2791: ** version 3.5.0 there is no mechanism for limiting the heap usage for
2792: ** individual threads.
2793: */
2794: void sqlite3_soft_heap_limit(int);
2795:
2796: /*
2797: ** CAPI3REF: Extract Metadata About A Column Of A Table
2798: **
2799: ** This routine
2800: ** returns meta-data about a specific column of a specific database
2801: ** table accessible using the connection handle passed as the first function
2802: ** argument.
2803: **
2804: ** The column is identified by the second, third and fourth parameters to
2805: ** this function. The second parameter is either the name of the database
2806: ** (i.e. "main", "temp" or an attached database) containing the specified
2807: ** table or NULL. If it is NULL, then all attached databases are searched
2808: ** for the table using the same algorithm as the database engine uses to
2809: ** resolve unqualified table references.
2810: **
2811: ** The third and fourth parameters to this function are the table and column
2812: ** name of the desired column, respectively. Neither of these parameters
2813: ** may be NULL.
2814: **
2815: ** Meta information is returned by writing to the memory locations passed as
2816: ** the 5th and subsequent parameters to this function. Any of these
2817: ** arguments may be NULL, in which case the corresponding element of meta
2818: ** information is ommitted.
2819: **
2820: ** <pre>
2821: ** Parameter Output Type Description
2822: ** -----------------------------------
2823: **
2824: ** 5th const char* Data type
2825: ** 6th const char* Name of the default collation sequence
2826: ** 7th int True if the column has a NOT NULL constraint
2827: ** 8th int True if the column is part of the PRIMARY KEY
2828: ** 9th int True if the column is AUTOINCREMENT
2829: ** </pre>
2830: **
2831: **
2832: ** The memory pointed to by the character pointers returned for the
2833: ** declaration type and collation sequence is valid only until the next
2834: ** call to any sqlite API function.
2835: **
2836: ** If the specified table is actually a view, then an error is returned.
2837: **
2838: ** If the specified column is "rowid", "oid" or "_rowid_" and an
2839: ** INTEGER PRIMARY KEY column has been explicitly declared, then the output
2840: ** parameters are set for the explicitly declared column. If there is no
2841: ** explicitly declared IPK column, then the output parameters are set as
2842: ** follows:
2843: **
2844: ** <pre>
2845: ** data type: "INTEGER"
2846: ** collation sequence: "BINARY"
2847: ** not null: 0
2848: ** primary key: 1
2849: ** auto increment: 0
2850: ** </pre>
2851: **
2852: ** This function may load one or more schemas from database files. If an
2853: ** error occurs during this process, or if the requested table or column
2854: ** cannot be found, an SQLITE error code is returned and an error message
2855: ** left in the database handle (to be retrieved using sqlite3_errmsg()).
2856: **
2857: ** This API is only available if the library was compiled with the
2858: ** SQLITE_ENABLE_COLUMN_METADATA preprocessor symbol defined.
2859: */
2860: int sqlite3_table_column_metadata(
2861: sqlite3 *db, /* Connection handle */
2862: const char *zDbName, /* Database name or NULL */
2863: const char *zTableName, /* Table name */
2864: const char *zColumnName, /* Column name */
2865: char const **pzDataType, /* OUTPUT: Declared data type */
2866: char const **pzCollSeq, /* OUTPUT: Collation sequence name */
2867: int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
2868: int *pPrimaryKey, /* OUTPUT: True if column part of PK */
2869: int *pAutoinc /* OUTPUT: True if column is auto-increment */
2870: );
2871:
2872: /*
2873: ** CAPI3REF: Load An Extension
2874: **
2875: ** Attempt to load an SQLite extension library contained in the file
2876: ** zFile. The entry point is zProc. zProc may be 0 in which case the
2877: ** name of the entry point defaults to "sqlite3_extension_init".
2878: **
2879: ** Return [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
2880: **
2881: ** If an error occurs and pzErrMsg is not 0, then fill *pzErrMsg with
2882: ** error message text. The calling function should free this memory
2883: ** by calling [sqlite3_free()].
2884: **
2885: ** Extension loading must be enabled using [sqlite3_enable_load_extension()]
2886: ** prior to calling this API or an error will be returned.
2887: */
2888: int sqlite3_load_extension(
2889: sqlite3 *db, /* Load the extension into this database connection */
2890: const char *zFile, /* Name of the shared library containing extension */
2891: const char *zProc, /* Entry point. Derived from zFile if 0 */
2892: char **pzErrMsg /* Put error message here if not 0 */
2893: );
2894:
2895: /*
2896: ** CAPI3REF: Enable Or Disable Extension Loading
2897: **
2898: ** So as not to open security holes in older applications that are
2899: ** unprepared to deal with extension loading, and as a means of disabling
2900: ** extension loading while evaluating user-entered SQL, the following
2901: ** API is provided to turn the [sqlite3_load_extension()] mechanism on and
2902: ** off. It is off by default. See ticket #1863.
2903: **
2904: ** Call this routine with onoff==1 to turn extension loading on
2905: ** and call it with onoff==0 to turn it back off again.
2906: */
2907: int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
2908:
2909: /*
2910: ** CAPI3REF: Make Arrangements To Automatically Load An Extension
2911: **
2912: ** Register an extension entry point that is automatically invoked
2913: ** whenever a new database connection is opened using
2914: ** [sqlite3_open()], [sqlite3_open16()], or [sqlite3_open_v2()].
2915: **
2916: ** This API can be invoked at program startup in order to register
2917: ** one or more statically linked extensions that will be available
2918: ** to all new database connections.
2919: **
2920: ** Duplicate extensions are detected so calling this routine multiple
2921: ** times with the same extension is harmless.
2922: **
2923: ** This routine stores a pointer to the extension in an array
2924: ** that is obtained from malloc(). If you run a memory leak
2925: ** checker on your program and it reports a leak because of this
2926: ** array, then invoke [sqlite3_automatic_extension_reset()] prior
2927: ** to shutdown to free the memory.
2928: **
2929: ** Automatic extensions apply across all threads.
2930: **
2931: ** This interface is experimental and is subject to change or
2932: ** removal in future releases of SQLite.
2933: */
2934: int sqlite3_auto_extension(void *xEntryPoint);
2935:
2936:
2937: /*
2938: ** CAPI3REF: Reset Automatic Extension Loading
2939: **
2940: ** Disable all previously registered automatic extensions. This
2941: ** routine undoes the effect of all prior [sqlite3_automatic_extension()]
2942: ** calls.
2943: **
2944: ** This call disabled automatic extensions in all threads.
2945: **
2946: ** This interface is experimental and is subject to change or
2947: ** removal in future releases of SQLite.
2948: */
2949: void sqlite3_reset_auto_extension(void);
2950:
2951:
2952: /*
2953: ****** EXPERIMENTAL - subject to change without notice **************
2954: **
2955: ** The interface to the virtual-table mechanism is currently considered
2956: ** to be experimental. The interface might change in incompatible ways.
2957: ** If this is a problem for you, do not use the interface at this time.
2958: **
2959: ** When the virtual-table mechanism stablizes, we will declare the
2960: ** interface fixed, support it indefinitely, and remove this comment.
2961: */
2962:
2963: /*
2964: ** Structures used by the virtual table interface
2965: */
2966: typedef struct sqlite3_vtab sqlite3_vtab;
2967: typedef struct sqlite3_index_info sqlite3_index_info;
2968: typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
2969: typedef struct sqlite3_module sqlite3_module;
2970:
2971: /*
2972: ** A module is a class of virtual tables. Each module is defined
2973: ** by an instance of the following structure. This structure consists
2974: ** mostly of methods for the module.
2975: */
2976: struct sqlite3_module {
2977: int iVersion;
2978: int (*xCreate)(sqlite3*, void *pAux,
2979: int argc, const char *const*argv,
2980: sqlite3_vtab **ppVTab, char**);
2981: int (*xConnect)(sqlite3*, void *pAux,
2982: int argc, const char *const*argv,
2983: sqlite3_vtab **ppVTab, char**);
2984: int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
2985: int (*xDisconnect)(sqlite3_vtab *pVTab);
2986: int (*xDestroy)(sqlite3_vtab *pVTab);
2987: int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
2988: int (*xClose)(sqlite3_vtab_cursor*);
2989: int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
2990: int argc, sqlite3_value **argv);
2991: int (*xNext)(sqlite3_vtab_cursor*);
2992: int (*xEof)(sqlite3_vtab_cursor*);
2993: int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
2994: int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
2995: int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
2996: int (*xBegin)(sqlite3_vtab *pVTab);
2997: int (*xSync)(sqlite3_vtab *pVTab);
2998: int (*xCommit)(sqlite3_vtab *pVTab);
2999: int (*xRollback)(sqlite3_vtab *pVTab);
3000: int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
3001: void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
3002: void **ppArg);
3003:
3004: int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
3005: };
3006:
3007: /*
3008: ** The sqlite3_index_info structure and its substructures is used to
3009: ** pass information into and receive the reply from the xBestIndex
3010: ** method of an sqlite3_module. The fields under **Inputs** are the
3011: ** inputs to xBestIndex and are read-only. xBestIndex inserts its
3012: ** results into the **Outputs** fields.
3013: **
3014: ** The aConstraint[] array records WHERE clause constraints of the
3015: ** form:
3016: **
3017: ** column OP expr
3018: **
3019: ** Where OP is =, <, <=, >, or >=. The particular operator is stored
3020: ** in aConstraint[].op. The index of the column is stored in
3021: ** aConstraint[].iColumn. aConstraint[].usable is TRUE if the
3022: ** expr on the right-hand side can be evaluated (and thus the constraint
3023: ** is usable) and false if it cannot.
3024: **
3025: ** The optimizer automatically inverts terms of the form "expr OP column"
3026: ** and makes other simplifications to the WHERE clause in an attempt to
3027: ** get as many WHERE clause terms into the form shown above as possible.
3028: ** The aConstraint[] array only reports WHERE clause terms in the correct
3029: ** form that refer to the particular virtual table being queried.
3030: **
3031: ** Information about the ORDER BY clause is stored in aOrderBy[].
3032: ** Each term of aOrderBy records a column of the ORDER BY clause.
3033: **
3034: ** The xBestIndex method must fill aConstraintUsage[] with information
3035: ** about what parameters to pass to xFilter. If argvIndex>0 then
3036: ** the right-hand side of the corresponding aConstraint[] is evaluated
3037: ** and becomes the argvIndex-th entry in argv. If aConstraintUsage[].omit
3038: ** is true, then the constraint is assumed to be fully handled by the
3039: ** virtual table and is not checked again by SQLite.
3040: **
3041: ** The idxNum and idxPtr values are recorded and passed into xFilter.
3042: ** sqlite3_free() is used to free idxPtr if needToFreeIdxPtr is true.
3043: **
3044: ** The orderByConsumed means that output from xFilter will occur in
3045: ** the correct order to satisfy the ORDER BY clause so that no separate
3046: ** sorting step is required.
3047: **
3048: ** The estimatedCost value is an estimate of the cost of doing the
3049: ** particular lookup. A full scan of a table with N entries should have
3050: ** a cost of N. A binary search of a table of N entries should have a
3051: ** cost of approximately log(N).
3052: */
3053: struct sqlite3_index_info {
3054: /* Inputs */
3055: int nConstraint; /* Number of entries in aConstraint */
3056: struct sqlite3_index_constraint {
3057: int iColumn; /* Column on left-hand side of constraint */
3058: unsigned char op; /* Constraint operator */
3059: unsigned char usable; /* True if this constraint is usable */
3060: int iTermOffset; /* Used internally - xBestIndex should ignore */
3061: } *aConstraint; /* Table of WHERE clause constraints */
3062: int nOrderBy; /* Number of terms in the ORDER BY clause */
3063: struct sqlite3_index_orderby {
3064: int iColumn; /* Column number */
3065: unsigned char desc; /* True for DESC. False for ASC. */
3066: } *aOrderBy; /* The ORDER BY clause */
3067:
3068: /* Outputs */
3069: struct sqlite3_index_constraint_usage {
3070: int argvIndex; /* if >0, constraint is part of argv to xFilter */
3071: unsigned char omit; /* Do not code a test for this constraint */
3072: } *aConstraintUsage;
3073: int idxNum; /* Number used to identify the index */
3074: char *idxStr; /* String, possibly obtained from sqlite3_malloc */
3075: int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
3076: int orderByConsumed; /* True if output is already ordered */
3077: double estimatedCost; /* Estimated cost of using this index */
3078: };
3079: #define SQLITE_INDEX_CONSTRAINT_EQ 2
3080: #define SQLITE_INDEX_CONSTRAINT_GT 4
3081: #define SQLITE_INDEX_CONSTRAINT_LE 8
3082: #define SQLITE_INDEX_CONSTRAINT_LT 16
3083: #define SQLITE_INDEX_CONSTRAINT_GE 32
3084: #define SQLITE_INDEX_CONSTRAINT_MATCH 64
3085:
3086: /*
3087: ** This routine is used to register a new module name with an SQLite
3088: ** connection. Module names must be registered before creating new
3089: ** virtual tables on the module, or before using preexisting virtual
3090: ** tables of the module.
3091: */
3092: int sqlite3_create_module(
3093: sqlite3 *db, /* SQLite connection to register module with */
3094: const char *zName, /* Name of the module */
3095: const sqlite3_module *, /* Methods for the module */
3096: void * /* Client data for xCreate/xConnect */
3097: );
3098:
3099: /*
3100: ** This routine is identical to the sqlite3_create_module() method above,
3101: ** except that it allows a destructor function to be specified. It is
3102: ** even more experimental than the rest of the virtual tables API.
3103: */
3104: int sqlite3_create_module_v2(
3105: sqlite3 *db, /* SQLite connection to register module with */
3106: const char *zName, /* Name of the module */
3107: const sqlite3_module *, /* Methods for the module */
3108: void *, /* Client data for xCreate/xConnect */
3109: void(*xDestroy)(void*) /* Module destructor function */
3110: );
3111:
3112: /*
3113: ** Every module implementation uses a subclass of the following structure
3114: ** to describe a particular instance of the module. Each subclass will
3115: ** be tailored to the specific needs of the module implementation. The
3116: ** purpose of this superclass is to define certain fields that are common
3117: ** to all module implementations.
3118: **
3119: ** Virtual tables methods can set an error message by assigning a
3120: ** string obtained from sqlite3_mprintf() to zErrMsg. The method should
3121: ** take care that any prior string is freed by a call to sqlite3_free()
3122: ** prior to assigning a new string to zErrMsg. After the error message
3123: ** is delivered up to the client application, the string will be automatically
3124: ** freed by sqlite3_free() and the zErrMsg field will be zeroed. Note
3125: ** that sqlite3_mprintf() and sqlite3_free() are used on the zErrMsg field
3126: ** since virtual tables are commonly implemented in loadable extensions which
3127: ** do not have access to sqlite3MPrintf() or sqlite3Free().
3128: */
3129: struct sqlite3_vtab {
3130: const sqlite3_module *pModule; /* The module for this virtual table */
3131: int nRef; /* Used internally */
3132: char *zErrMsg; /* Error message from sqlite3_mprintf() */
3133: /* Virtual table implementations will typically add additional fields */
3134: };
3135:
3136: /* Every module implementation uses a subclass of the following structure
3137: ** to describe cursors that point into the virtual table and are used
3138: ** to loop through the virtual table. Cursors are created using the
3139: ** xOpen method of the module. Each module implementation will define
3140: ** the content of a cursor structure to suit its own needs.
3141: **
3142: ** This superclass exists in order to define fields of the cursor that
3143: ** are common to all implementations.
3144: */
3145: struct sqlite3_vtab_cursor {
3146: sqlite3_vtab *pVtab; /* Virtual table of this cursor */
3147: /* Virtual table implementations will typically add additional fields */
3148: };
3149:
3150: /*
3151: ** The xCreate and xConnect methods of a module use the following API
3152: ** to declare the format (the names and datatypes of the columns) of
3153: ** the virtual tables they implement.
3154: */
3155: int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable);
3156:
3157: /*
3158: ** Virtual tables can provide alternative implementations of functions
3159: ** using the xFindFunction method. But global versions of those functions
3160: ** must exist in order to be overloaded.
3161: **
3162: ** This API makes sure a global version of a function with a particular
3163: ** name and number of parameters exists. If no such function exists
3164: ** before this API is called, a new function is created. The implementation
3165: ** of the new function always causes an exception to be thrown. So
3166: ** the new function is not good for anything by itself. Its only
3167: ** purpose is to be a place-holder function that can be overloaded
3168: ** by virtual tables.
3169: **
3170: ** This API should be considered part of the virtual table interface,
3171: ** which is experimental and subject to change.
3172: */
3173: int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
3174:
3175: /*
3176: ** The interface to the virtual-table mechanism defined above (back up
3177: ** to a comment remarkably similar to this one) is currently considered
3178: ** to be experimental. The interface might change in incompatible ways.
3179: ** If this is a problem for you, do not use the interface at this time.
3180: **
3181: ** When the virtual-table mechanism stabilizes, we will declare the
3182: ** interface fixed, support it indefinitely, and remove this comment.
3183: **
3184: ****** EXPERIMENTAL - subject to change without notice **************
3185: */
3186:
3187: /*
3188: ** CAPI3REF: A Handle To An Open BLOB
3189: **
3190: ** An instance of the following opaque structure is used to
3191: ** represent an blob-handle. A blob-handle is created by
3192: ** [sqlite3_blob_open()] and destroyed by [sqlite3_blob_close()].
3193: ** The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
3194: ** can be used to read or write small subsections of the blob.
3195: ** The [sqlite3_blob_bytes()] interface returns the size of the
3196: ** blob in bytes.
3197: */
3198: typedef struct sqlite3_blob sqlite3_blob;
3199:
3200: /*
3201: ** CAPI3REF: Open A BLOB For Incremental I/O
3202: **
3203: ** Open a handle to the blob located in row iRow,, column zColumn,
3204: ** table zTable in database zDb. i.e. the same blob that would
3205: ** be selected by:
3206: **
3207: ** <pre>
3208: ** SELECT zColumn FROM zDb.zTable WHERE rowid = iRow;
3209: ** </pre>
3210: **
3211: ** If the flags parameter is non-zero, the blob is opened for
3212: ** read and write access. If it is zero, the blob is opened for read
3213: ** access.
3214: **
3215: ** On success, [SQLITE_OK] is returned and the new
3216: ** [sqlite3_blob | blob handle] is written to *ppBlob.
3217: ** Otherwise an error code is returned and
3218: ** any value written to *ppBlob should not be used by the caller.
3219: ** This function sets the database-handle error code and message
3220: ** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()].
3221: */
3222: int sqlite3_blob_open(
3223: sqlite3*,
3224: const char *zDb,
3225: const char *zTable,
3226: const char *zColumn,
3227: sqlite3_int64 iRow,
3228: int flags,
3229: sqlite3_blob **ppBlob
3230: );
3231:
3232: /*
3233: ** CAPI3REF: Close A BLOB Handle
3234: **
3235: ** Close an open [sqlite3_blob | blob handle].
3236: */
3237: int sqlite3_blob_close(sqlite3_blob *);
3238:
3239: /*
3240: ** CAPI3REF: Return The Size Of An Open BLOB
3241: **
3242: ** Return the size in bytes of the blob accessible via the open
3243: ** [sqlite3_blob | blob-handle] passed as an argument.
3244: */
3245: int sqlite3_blob_bytes(sqlite3_blob *);
3246:
3247: /*
3248: ** CAPI3REF: Read Data From A BLOB Incrementally
3249: **
3250: ** This function is used to read data from an open
3251: ** [sqlite3_blob | blob-handle] into a caller supplied buffer.
3252: ** n bytes of data are copied into buffer
3253: ** z from the open blob, starting at offset iOffset.
3254: **
3255: ** On success, SQLITE_OK is returned. Otherwise, an
3256: ** [SQLITE_ERROR | SQLite error code] or an
3257: ** [SQLITE_IOERR_READ | extended error code] is returned.
1.1 misha 3258: */
1.2 misha 3259: int sqlite3_blob_read(sqlite3_blob *, void *z, int n, int iOffset);
3260:
3261: /*
3262: ** CAPI3REF: Write Data Into A BLOB Incrementally
3263: **
3264: ** This function is used to write data into an open
3265: ** [sqlite3_blob | blob-handle] from a user supplied buffer.
3266: ** n bytes of data are copied from the buffer
3267: ** pointed to by z into the open blob, starting at offset iOffset.
3268: **
3269: ** If the [sqlite3_blob | blob-handle] passed as the first argument
3270: ** was not opened for writing (the flags parameter to [sqlite3_blob_open()]
3271: *** was zero), this function returns [SQLITE_READONLY].
3272: **
3273: ** This function may only modify the contents of the blob, it is
3274: ** not possible to increase the size of a blob using this API. If
3275: ** offset iOffset is less than n bytes from the end of the blob,
3276: ** [SQLITE_ERROR] is returned and no data is written.
3277: **
3278: ** On success, SQLITE_OK is returned. Otherwise, an
3279: ** [SQLITE_ERROR | SQLite error code] or an
3280: ** [SQLITE_IOERR_READ | extended error code] is returned.
3281: */
3282: int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
3283:
3284: /*
3285: ** CAPI3REF: Virtual File System Objects
3286: **
3287: ** A virtual filesystem (VFS) is an [sqlite3_vfs] object
3288: ** that SQLite uses to interact
3289: ** with the underlying operating system. Most builds come with a
3290: ** single default VFS that is appropriate for the host computer.
3291: ** New VFSes can be registered and existing VFSes can be unregistered.
3292: ** The following interfaces are provided.
3293: **
3294: ** The sqlite3_vfs_find() interface returns a pointer to a VFS given its
3295: ** name. Names are case sensitive. If there is no match, a NULL
3296: ** pointer is returned. If zVfsName is NULL then the default
3297: ** VFS is returned.
3298: **
3299: ** New VFSes are registered with sqlite3_vfs_register(). Each
3300: ** new VFS becomes the default VFS if the makeDflt flag is set.
3301: ** The same VFS can be registered multiple times without injury.
3302: ** To make an existing VFS into the default VFS, register it again
3303: ** with the makeDflt flag set. If two different VFSes with the
3304: ** same name are registered, the behavior is undefined. If a
3305: ** VFS is registered with a name that is NULL or an empty string,
3306: ** then the behavior is undefined.
3307: **
3308: ** Unregister a VFS with the sqlite3_vfs_unregister() interface.
3309: ** If the default VFS is unregistered, another VFS is chosen as
3310: ** the default. The choice for the new VFS is arbitrary.
3311: */
3312: sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
3313: int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
3314: int sqlite3_vfs_unregister(sqlite3_vfs*);
3315:
3316: /*
3317: ** CAPI3REF: Mutexes
3318: **
3319: ** The SQLite core uses these routines for thread
3320: ** synchronization. Though they are intended for internal
3321: ** use by SQLite, code that links against SQLite is
3322: ** permitted to use any of these routines.
3323: **
3324: ** The SQLite source code contains multiple implementations
3325: ** of these mutex routines. An appropriate implementation
3326: ** is selected automatically at compile-time. The following
3327: ** implementations are available in the SQLite core:
3328: **
3329: ** <ul>
3330: ** <li> SQLITE_MUTEX_OS2
3331: ** <li> SQLITE_MUTEX_PTHREAD
3332: ** <li> SQLITE_MUTEX_W32
3333: ** <li> SQLITE_MUTEX_NOOP
3334: ** </ul>
3335: **
3336: ** The SQLITE_MUTEX_NOOP implementation is a set of routines
3337: ** that does no real locking and is appropriate for use in
3338: ** a single-threaded application. The SQLITE_MUTEX_OS2,
3339: ** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations
3340: ** are appropriate for use on os/2, unix, and windows.
3341: **
3342: ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
3343: ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
3344: ** implementation is included with the library. The
3345: ** mutex interface routines defined here become external
3346: ** references in the SQLite library for which implementations
3347: ** must be provided by the application. This facility allows an
3348: ** application that links against SQLite to provide its own mutex
3349: ** implementation without having to modify the SQLite core.
3350: **
3351: ** The sqlite3_mutex_alloc() routine allocates a new
3352: ** mutex and returns a pointer to it. If it returns NULL
3353: ** that means that a mutex could not be allocated. SQLite
3354: ** will unwind its stack and return an error. The argument
3355: ** to sqlite3_mutex_alloc() is one of these integer constants:
3356: **
3357: ** <ul>
3358: ** <li> SQLITE_MUTEX_FAST
3359: ** <li> SQLITE_MUTEX_RECURSIVE
3360: ** <li> SQLITE_MUTEX_STATIC_MASTER
3361: ** <li> SQLITE_MUTEX_STATIC_MEM
3362: ** <li> SQLITE_MUTEX_STATIC_MEM2
3363: ** <li> SQLITE_MUTEX_STATIC_PRNG
3364: ** <li> SQLITE_MUTEX_STATIC_LRU
3365: ** </ul>
3366: **
3367: ** The first two constants cause sqlite3_mutex_alloc() to create
3368: ** a new mutex. The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
3369: ** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
3370: ** The mutex implementation does not need to make a distinction
3371: ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
3372: ** not want to. But SQLite will only request a recursive mutex in
3373: ** cases where it really needs one. If a faster non-recursive mutex
3374: ** implementation is available on the host platform, the mutex subsystem
3375: ** might return such a mutex in response to SQLITE_MUTEX_FAST.
3376: **
3377: ** The other allowed parameters to sqlite3_mutex_alloc() each return
3378: ** a pointer to a static preexisting mutex. Four static mutexes are
3379: ** used by the current version of SQLite. Future versions of SQLite
3380: ** may add additional static mutexes. Static mutexes are for internal
3381: ** use by SQLite only. Applications that use SQLite mutexes should
3382: ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
3383: ** SQLITE_MUTEX_RECURSIVE.
3384: **
3385: ** Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
3386: ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
3387: ** returns a different mutex on every call. But for the static
3388: ** mutex types, the same mutex is returned on every call that has
3389: ** the same type number.
3390: **
3391: ** The sqlite3_mutex_free() routine deallocates a previously
3392: ** allocated dynamic mutex. SQLite is careful to deallocate every
3393: ** dynamic mutex that it allocates. The dynamic mutexes must not be in
3394: ** use when they are deallocated. Attempting to deallocate a static
3395: ** mutex results in undefined behavior. SQLite never deallocates
3396: ** a static mutex.
3397: **
3398: ** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
3399: ** to enter a mutex. If another thread is already within the mutex,
3400: ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
3401: ** SQLITE_BUSY. The sqlite3_mutex_try() interface returns SQLITE_OK
3402: ** upon successful entry. Mutexes created using SQLITE_MUTEX_RECURSIVE can
3403: ** be entered multiple times by the same thread. In such cases the,
3404: ** mutex must be exited an equal number of times before another thread
3405: ** can enter. If the same thread tries to enter any other kind of mutex
3406: ** more than once, the behavior is undefined. SQLite will never exhibit
3407: ** such behavior in its own use of mutexes.
3408: **
3409: ** Some systems (ex: windows95) do not the operation implemented by
3410: ** sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() will
3411: ** always return SQLITE_BUSY. The SQLite core only ever uses
3412: ** sqlite3_mutex_try() as an optimization so this is acceptable behavior.
3413: **
3414: ** The sqlite3_mutex_leave() routine exits a mutex that was
3415: ** previously entered by the same thread. The behavior
3416: ** is undefined if the mutex is not currently entered by the
3417: ** calling thread or is not currently allocated. SQLite will
3418: ** never do either.
3419: **
3420: ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
3421: */
3422: sqlite3_mutex *sqlite3_mutex_alloc(int);
3423: void sqlite3_mutex_free(sqlite3_mutex*);
3424: void sqlite3_mutex_enter(sqlite3_mutex*);
3425: int sqlite3_mutex_try(sqlite3_mutex*);
3426: void sqlite3_mutex_leave(sqlite3_mutex*);
3427:
3428: /*
3429: ** CAPI3REF: Mutex Verifcation Routines
3430: **
3431: ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
3432: ** are intended for use inside assert() statements. The SQLite core
3433: ** never uses these routines except inside an assert() and applications
3434: ** are advised to follow the lead of the core. The core only
3435: ** provides implementations for these routines when it is compiled
3436: ** with the SQLITE_DEBUG flag. External mutex implementations
3437: ** are only required to provide these routines if SQLITE_DEBUG is
3438: ** defined and if NDEBUG is not defined.
3439: **
3440: ** These routines should return true if the mutex in their argument
3441: ** is held or not held, respectively, by the calling thread.
3442: **
3443: ** The implementation is not required to provided versions of these
3444: ** routines that actually work.
3445: ** If the implementation does not provide working
3446: ** versions of these routines, it should at least provide stubs
3447: ** that always return true so that one does not get spurious
3448: ** assertion failures.
3449: **
3450: ** If the argument to sqlite3_mutex_held() is a NULL pointer then
3451: ** the routine should return 1. This seems counter-intuitive since
3452: ** clearly the mutex cannot be held if it does not exist. But the
3453: ** the reason the mutex does not exist is because the build is not
3454: ** using mutexes. And we do not want the assert() containing the
3455: ** call to sqlite3_mutex_held() to fail, so a non-zero return is
3456: ** the appropriate thing to do. The sqlite3_mutex_notheld()
3457: ** interface should also return 1 when given a NULL pointer.
3458: */
3459: int sqlite3_mutex_held(sqlite3_mutex*);
3460: int sqlite3_mutex_notheld(sqlite3_mutex*);
3461:
3462: /*
3463: ** CAPI3REF: Mutex Types
3464: **
3465: ** The [sqlite3_mutex_alloc()] interface takes a single argument
3466: ** which is one of these integer constants.
3467: */
3468: #define SQLITE_MUTEX_FAST 0
3469: #define SQLITE_MUTEX_RECURSIVE 1
3470: #define SQLITE_MUTEX_STATIC_MASTER 2
3471: #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
3472: #define SQLITE_MUTEX_STATIC_MEM2 4 /* sqlite3_release_memory() */
3473: #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */
3474: #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
3475:
3476: /*
3477: ** CAPI3REF: Low-Level Control Of Database Files
3478: **
3479: ** The [sqlite3_file_control()] interface makes a direct call to the
3480: ** xFileControl method for the [sqlite3_io_methods] object associated
3481: ** with a particular database identified by the second argument. The
3482: ** name of the database is the name assigned to the database by the
3483: ** <a href="lang_attach.html">ATTACH</a> SQL command that opened the
3484: ** database. To control the main database file, use the name "main"
3485: ** or a NULL pointer. The third and fourth parameters to this routine
3486: ** are passed directly through to the second and third parameters of
3487: ** the xFileControl method. The return value of the xFileControl
3488: ** method becomes the return value of this routine.
3489: **
3490: ** If the second parameter (zDbName) does not match the name of any
3491: ** open database file, then SQLITE_ERROR is returned. This error
3492: ** code is not remembered and will not be recalled by [sqlite3_errcode()]
3493: ** or [sqlite3_errmsg()]. The underlying xFileControl method might
3494: ** also return SQLITE_ERROR. There is no way to distinguish between
3495: ** an incorrect zDbName and an SQLITE_ERROR return from the underlying
3496: ** xFileControl method.
3497: **
3498: ** See also: [SQLITE_FCNTL_LOCKSTATE]
3499: */
3500: int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
3501:
3502: /*
3503: ** Undo the hack that converts floating point types to integer for
3504: ** builds on processors without floating point support.
3505: */
3506: #ifdef SQLITE_OMIT_FLOATING_POINT
3507: # undef double
3508: #endif
1.1 misha 3509:
3510: #ifdef __cplusplus
3511: } /* End of the 'extern "C"' block */
3512: #endif
3513: #endif
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