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Overview
Comment: | Clean up test_journal.c to make it easier to follow. (CVS 6140) |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | trunk |
Files: | files | file ages | folders |
SHA1: |
5a28c7c7b45655dcfd0da4898e77d024 |
User & Date: | danielk1977 2009-01-08 12:05:56.000 |
Context
2009-01-08
| ||
14:36 | Allow database files to be created in the root directory on unix. Ticket #3570. (CVS 6141) (check-in: 81014334ad user: drh tags: trunk) | |
12:05 | Clean up test_journal.c to make it easier to follow. (CVS 6140) (check-in: 5a28c7c7b4 user: danielk1977 tags: trunk) | |
03:11 | Increase test coverage of where.c. Make sure OR-optimization works on UPDATE and DELETE in addition to SELECT. (Bug found by coverage tests.) (CVS 6139) (check-in: 4b2c08e898 user: drh tags: trunk) | |
Changes
Changes to src/test_journal.c.
1 2 3 4 5 6 7 8 9 10 11 12 13 | /* ** 2008 Jan 22 ** ** The author disclaims copyright to this source code. In place of ** a legal notice, here is a blessing: ** ** May you do good and not evil. ** May you find forgiveness for yourself and forgive others. ** May you share freely, never taking more than you give. ** ****************************************************************************** ** ** This file contains code for a VFS layer that acts as a wrapper around | | < < < | < | | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 | /* ** 2008 Jan 22 ** ** The author disclaims copyright to this source code. In place of ** a legal notice, here is a blessing: ** ** May you do good and not evil. ** May you find forgiveness for yourself and forgive others. ** May you share freely, never taking more than you give. ** ****************************************************************************** ** ** This file contains code for a VFS layer that acts as a wrapper around ** an existing VFS. The code in this file attempts to verify that SQLite ** correctly populates and syncs a journal file before writing to a ** corresponding database file. ** ** $Id: test_journal.c,v 1.8 2009/01/08 12:05:56 danielk1977 Exp $ */ #if SQLITE_TEST /* This file is used for testing only */ #include "sqlite3.h" #include "sqliteInt.h" /* ** INTERFACE ** ** The public interface to this wrapper VFS is two functions: ** ** jt_register() ** jt_unregister() ** ** See header comments associated with those two functions below for ** details. ** ** LIMITATIONS ** ** This wrapper will not work if "PRAGMA synchronous = off" is used. ** ** OPERATION ** ** Starting a Transaction: ** ** When a write-transaction is started, the contents of the database is ** inspected and the following data stored as part of the database file ** handle (type struct jt_file): ** ** a) The page-size of the database file. ** b) The number of pages that are in the database file. ** c) The set of page numbers corresponding to free-list leaf pages. ** d) A check-sum for every page in the database file. ** ** The start of a write-transaction is deemed to have occured when a ** 28-byte journal header is written to byte offset 0 of the journal ** file. ** ** Syncing the Journal File: ** ** Whenever the xSync method is invoked to sync a journal-file, the ** contents of the journal file are read. For each page written to ** the journal file, a check-sum is calculated and compared to the ** check-sum calculated for the corresponding database page when the ** write-transaction was initialized. The success of the comparison ** is assert()ed. So if SQLite has written something other than the ** original content to the database file, an assert() will fail. ** ** Additionally, the set of page numbers for which records exist in ** the journal file is added to (unioned with) the set of page numbers ** corresponding to free-list leaf pages collected when the ** write-transaction was initialized. This set comprises the page-numbers ** corresponding to those pages that SQLite may now safely modify. ** ** Writing to the Database File: ** ** When a block of data is written to a database file, the following ** invariants are asserted: ** ** a) That the block of data is an aligned block of page-size bytes. ** ** b) That if the page being written did not exist when the ** transaction was started (i.e. the database file is growing), then ** the journal-file must have been synced at least once since ** the start of the transaction. ** ** c) That if the page being written did exist when the transaction ** was started, then the page must have either been a free-list ** leaf page at the start of the transaction, or else must have ** been stored in the journal file prior to the most recent sync. ** ** Closing a Transaction: ** ** When a transaction is closed, all data collected at the start of ** the transaction, or following an xSync of a journal-file, is ** discarded. The end of a transaction is recognized when any one ** of the following occur: ** ** a) A block of zeroes (or anything else that is not a valid ** journal-header) is written to the start of the journal file. ** ** b) A journal file is truncated to zero bytes in size using xTruncate. ** ** c) The journal file is deleted using xDelete. */ /* ** Maximum pathname length supported by the jt backend. */ #define JT_MAX_PATHNAME 512 /* |
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44 45 46 47 48 49 50 51 52 53 54 55 56 57 | /* The following are only used by database file file handles */ int eLock; /* Current lock held on the file */ u32 nPage; /* Size of file in pages when transaction started */ u32 nPagesize; /* Page size when transaction started */ Bitvec *pWritable; /* Bitvec of pages that may be written to the file */ u32 *aCksum; /* Checksum for first nPage pages */ /* Only used by journal file-handles */ sqlite3_int64 iMaxOff; /* Maximum offset written to this transaction */ jt_file *pNext; /* All files are stored in a linked list */ sqlite3_file *pReal; /* The file handle for the underlying vfs */ }; | > | 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 | /* The following are only used by database file file handles */ int eLock; /* Current lock held on the file */ u32 nPage; /* Size of file in pages when transaction started */ u32 nPagesize; /* Page size when transaction started */ Bitvec *pWritable; /* Bitvec of pages that may be written to the file */ u32 *aCksum; /* Checksum for first nPage pages */ int nSync; /* Number of times journal file has been synced */ /* Only used by journal file-handles */ sqlite3_int64 iMaxOff; /* Maximum offset written to this transaction */ jt_file *pNext; /* All files are stored in a linked list */ sqlite3_file *pReal; /* The file handle for the underlying vfs */ }; |
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75 76 77 78 79 80 81 | /* ** Method declarations for jt_vfs. */ static int jtOpen(sqlite3_vfs*, const char *, sqlite3_file*, int , int *); static int jtDelete(sqlite3_vfs*, const char *zName, int syncDir); static int jtAccess(sqlite3_vfs*, const char *zName, int flags, int *); static int jtFullPathname(sqlite3_vfs*, const char *zName, int, char *zOut); | < < < < < < < < < | 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 | /* ** Method declarations for jt_vfs. */ static int jtOpen(sqlite3_vfs*, const char *, sqlite3_file*, int , int *); static int jtDelete(sqlite3_vfs*, const char *zName, int syncDir); static int jtAccess(sqlite3_vfs*, const char *zName, int flags, int *); static int jtFullPathname(sqlite3_vfs*, const char *zName, int, char *zOut); static void *jtDlOpen(sqlite3_vfs*, const char *zFilename); static void jtDlError(sqlite3_vfs*, int nByte, char *zErrMsg); static void (*jtDlSym(sqlite3_vfs*,void*, const char *zSymbol))(void); static void jtDlClose(sqlite3_vfs*, void*); static int jtRandomness(sqlite3_vfs*, int nByte, char *zOut); static int jtSleep(sqlite3_vfs*, int microseconds); static int jtCurrentTime(sqlite3_vfs*, double*); static sqlite3_vfs jt_vfs = { 1, /* iVersion */ sizeof(jt_file), /* szOsFile */ JT_MAX_PATHNAME, /* mxPathname */ 0, /* pNext */ JT_VFS_NAME, /* zName */ 0, /* pAppData */ jtOpen, /* xOpen */ jtDelete, /* xDelete */ jtAccess, /* xAccess */ jtFullPathname, /* xFullPathname */ jtDlOpen, /* xDlOpen */ jtDlError, /* xDlError */ jtDlSym, /* xDlSym */ jtDlClose, /* xDlClose */ jtRandomness, /* xRandomness */ jtSleep, /* xSleep */ jtCurrentTime /* xCurrentTime */ }; static sqlite3_io_methods jt_io_methods = { 1, /* iVersion */ |
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129 130 131 132 133 134 135 | jtCheckReservedLock, /* xCheckReservedLock */ jtFileControl, /* xFileControl */ jtSectorSize, /* xSectorSize */ jtDeviceCharacteristics /* xDeviceCharacteristics */ }; struct JtGlobal { | | | > > > > > > | 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 | jtCheckReservedLock, /* xCheckReservedLock */ jtFileControl, /* xFileControl */ jtSectorSize, /* xSectorSize */ jtDeviceCharacteristics /* xDeviceCharacteristics */ }; struct JtGlobal { sqlite3_vfs *pVfs; /* Parent VFS */ jt_file *pList; /* List of all open files */ }; static struct JtGlobal g = {0, 0}; /* ** The jt_file pointed to by the argument may or may not be a file-handle ** open on a main database file. If it is, and a transaction is currently ** opened on the file, then discard all transaction related data. */ static void closeTransaction(jt_file *p){ sqlite3BitvecDestroy(p->pWritable); sqlite3_free(p->aCksum); p->pWritable = 0; p->aCksum = 0; p->nSync = 0; } /* ** Close an jt-file. */ static int jtClose(sqlite3_file *pFile){ jt_file **pp; |
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171 172 173 174 175 176 177 178 | sqlite_int64 iOfst ){ jt_file *p = (jt_file *)pFile; return sqlite3OsRead(p->pReal, zBuf, iAmt, iOfst); } static jt_file *locateDatabaseHandle(const char *zJournal){ | > > > > > > > > > > > > > > | | > > > > < < < < < < < | < < < < < < < < < < | | < | | | < < | < < < < | < < < < < < < < < < < < < < | < < | > > > | | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 | sqlite_int64 iOfst ){ jt_file *p = (jt_file *)pFile; return sqlite3OsRead(p->pReal, zBuf, iAmt, iOfst); } /* ** Parameter zJournal is the name of a journal file that is currently ** open. This function locates and returns the handle opened on the ** corresponding database file by the pager that currently has the ** journal file opened. This file-handle is identified by the ** following properties: ** ** a) SQLITE_OPEN_MAIN_DB was specified when the file was opened. ** ** b) The file-name specified when the file was opened matches ** all but the final 8 characters of the journal file name. ** ** c) There is currently a reserved lock on the file. **/ static jt_file *locateDatabaseHandle(const char *zJournal){ jt_file *pMain = 0; for(pMain=g.pList; pMain; pMain=pMain->pNext){ int nName = strlen(zJournal) - strlen("-journal"); if( (pMain->flags&SQLITE_OPEN_MAIN_DB) && (strlen(pMain->zName)==nName) && 0==memcmp(pMain->zName, zJournal, nName) && (pMain->eLock>=SQLITE_LOCK_RESERVED) ){ break; } } return pMain; } /* ** Parameter z points to a buffer of 4 bytes in size containing a ** unsigned 32-bit integer stored in big-endian format. Decode the ** integer and return its value. */ static u32 decodeUint32(const unsigned char *z){ return (z[0]<<24) + (z[1]<<16) + (z[2]<<8) + z[3]; } /* ** Calculate a checksum from the buffer of length n bytes pointed to ** by parameter z. */ static u32 genCksum(const unsigned char *z, int n){ int i; u32 cksum = 0; for(i=0; i<n; i++){ cksum = cksum + z[i] + (cksum<<3); } return cksum; } /* ** The first argument, zBuf, points to a buffer containing a 28 byte ** serialized journal header. This function deserializes four of the ** integer fields contained in the journal header and writes their ** values to the output variables. ** ** SQLITE_OK is returned if the journal-header is successfully ** decoded. Otherwise, SQLITE_ERROR. */ static int decodeJournalHdr( const unsigned char *zBuf, /* Input: 28 byte journal header */ u32 *pnRec, /* Out: Number of journalled records */ u32 *pnPage, /* Out: Original database page count */ u32 *pnSector, /* Out: Sector size in bytes */ u32 *pnPagesize /* Out: Page size in bytes */ ){ unsigned char aMagic[] = { 0xd9, 0xd5, 0x05, 0xf9, 0x20, 0xa1, 0x63, 0xd7 }; if( memcmp(aMagic, zBuf, 8) ) return SQLITE_ERROR; if( pnRec ) *pnRec = decodeUint32(&zBuf[8]); if( pnPage ) *pnPage = decodeUint32(&zBuf[16]); if( pnSector ) *pnSector = decodeUint32(&zBuf[20]); if( pnPagesize ) *pnPagesize = decodeUint32(&zBuf[24]); return SQLITE_OK; } /* ** This function is called when a new transaction is opened, just after ** the first journal-header is written to the journal file. */ static int openTransaction(jt_file *pMain, jt_file *pJournal){ unsigned char *aData; sqlite3_file *p = pMain->pReal; int rc = SQLITE_OK; aData = sqlite3_malloc(pMain->nPagesize); pMain->pWritable = sqlite3BitvecCreate(pMain->nPage); pMain->aCksum = sqlite3_malloc(sizeof(u32) * (pMain->nPage + 1)); pJournal->iMaxOff = 0; if( !pMain->pWritable || !pMain->aCksum || !aData ){ rc = SQLITE_IOERR_NOMEM; }else if( pMain->nPage>0 ){ u32 iTrunk; /* Read the database free-list. Add the page-number for each free-list ** leaf to the jt_file.pWritable bitvec. */ rc = sqlite3OsRead(p, aData, pMain->nPagesize, 0); iTrunk = decodeUint32(&aData[32]); while( rc==SQLITE_OK && iTrunk>0 ){ u32 nLeaf; u32 iLeaf; sqlite3_int64 iOff = (iTrunk-1)*pMain->nPagesize; rc = sqlite3OsRead(p, aData, pMain->nPagesize, iOff); nLeaf = decodeUint32(&aData[4]); for(iLeaf=0; rc==SQLITE_OK && iLeaf<nLeaf; iLeaf++){ u32 pgno = decodeUint32(&aData[8+4*iLeaf]); sqlite3BitvecSet(pMain->pWritable, pgno); } iTrunk = decodeUint32(aData); } /* Calculate and store a checksum for each page in the database file. */ if( rc==SQLITE_OK ){ int ii; for(ii=0; rc==SQLITE_OK && ii<pMain->nPage; ii++){ i64 iOff = (i64)(pMain->nPagesize) * (i64)ii; rc = sqlite3OsRead(pMain->pReal, aData, pMain->nPagesize, iOff); pMain->aCksum[ii] = genCksum(aData, pMain->nPagesize); } } } sqlite3_free(aData); return rc; } /* ** Write data to an jt-file. */ static int jtWrite( sqlite3_file *pFile, |
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289 290 291 292 293 294 295 | /* Zeroing the first journal-file header. This is the end of a ** transaction. */ closeTransaction(pMain); }else{ /* Writing the first journal header to a journal file. This happens ** when a transaction is first started. */ int rc; | < < < < < < < | < < < < | > > > | 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 | /* Zeroing the first journal-file header. This is the end of a ** transaction. */ closeTransaction(pMain); }else{ /* Writing the first journal header to a journal file. This happens ** when a transaction is first started. */ int rc; if( SQLITE_OK!=(rc=openTransaction(pMain, p)) ){ return rc; } } } if( p->iMaxOff<(iOfst + iAmt) ){ p->iMaxOff = iOfst + iAmt; } } if( p->flags&SQLITE_OPEN_MAIN_DB && p->pWritable ){ u32 pgno = iOfst/p->nPagesize + 1; assert( iAmt==p->nPagesize && (iOfst%p->nPagesize)==0 ); assert( pgno<=p->nPage || p->nSync>0 ); assert( pgno>p->nPage || sqlite3BitvecTest(p->pWritable, pgno) ); } return sqlite3OsWrite(p->pReal, zBuf, iAmt, iOfst); } /* |
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348 349 350 351 352 353 354 | ** page in the journal to the Bitvec object passed as the second argument. */ static int readJournalFile(jt_file *p, jt_file *pMain){ int rc = SQLITE_OK; unsigned char zBuf[28]; sqlite3_file *pReal = p->pReal; sqlite3_int64 iOff = 0; | | | < > > > < > > < | < < < | 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 | ** page in the journal to the Bitvec object passed as the second argument. */ static int readJournalFile(jt_file *p, jt_file *pMain){ int rc = SQLITE_OK; unsigned char zBuf[28]; sqlite3_file *pReal = p->pReal; sqlite3_int64 iOff = 0; sqlite3_int64 iSize = p->iMaxOff; unsigned char *aPage; aPage = sqlite3_malloc(pMain->nPagesize); if( !aPage ){ return SQLITE_IOERR_NOMEM; } while( rc==SQLITE_OK && iOff<iSize ){ u32 nRec, nPage, nSector, nPagesize; u32 ii; /* Read and decode the next journal-header from the journal file. */ rc = sqlite3OsRead(pReal, zBuf, 28, iOff); if( rc!=SQLITE_OK || decodeJournalHdr(zBuf, &nRec, &nPage, &nSector, &nPagesize) ){ goto finish_rjf; } iOff += nSector; if( nRec==0 ){ /* A trick. There might be another journal-header immediately ** following this one. In this case, 0 records means 0 records, ** not "read until the end of the file". See also ticket #2565. */ if( iSize>=(iOff+nSector) ){ rc = sqlite3OsRead(pReal, zBuf, 28, iOff); if( rc!=SQLITE_OK || 0==decodeJournalHdr(zBuf, 0, 0, 0, 0) ){ continue; } } nRec = (iSize-iOff) / (pMain->nPagesize+8); } /* Read all the records that follow the journal-header just read. */ for(ii=0; rc==SQLITE_OK && ii<nRec && iOff<iSize; ii++){ u32 pgno; rc = sqlite3OsRead(pReal, zBuf, 4, iOff); if( rc==SQLITE_OK ){ pgno = decodeUint32(zBuf); if( pgno>0 && pgno<=pMain->nPage ){ if( 0==sqlite3BitvecTest(pMain->pWritable, pgno) ){ rc = sqlite3OsRead(pReal, aPage, pMain->nPagesize, iOff+4); if( rc==SQLITE_OK ){ u32 cksum = genCksum(aPage, pMain->nPagesize); assert( cksum==pMain->aCksum[pgno-1] ); } } sqlite3BitvecSet(pMain->pWritable, pgno); } iOff += (8 + pMain->nPagesize); } |
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435 436 437 438 439 440 441 442 443 444 445 446 447 448 | ** this journal file. */ pMain = locateDatabaseHandle(p->zName); assert(pMain); /* Set the bitvec values */ if( pMain->pWritable ){ rc = readJournalFile(p, pMain); if( rc!=SQLITE_OK ){ return rc; } } } | > | 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 | ** this journal file. */ pMain = locateDatabaseHandle(p->zName); assert(pMain); /* Set the bitvec values */ if( pMain->pWritable ){ pMain->nSync++; rc = readJournalFile(p, pMain); if( rc!=SQLITE_OK ){ return rc; } } } |
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588 589 590 591 592 593 594 | const char *zPath, int nOut, char *zOut ){ return sqlite3OsFullPathname(g.pVfs, zPath, nOut, zOut); } | < | | | | < | 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 | const char *zPath, int nOut, char *zOut ){ return sqlite3OsFullPathname(g.pVfs, zPath, nOut, zOut); } /* ** Open the dynamic library located at zPath and return a handle. */ static void *jtDlOpen(sqlite3_vfs *pVfs, const char *zPath){ return g.pVfs->xDlOpen(g.pVfs, zPath); } /* ** Populate the buffer zErrMsg (size nByte bytes) with a human readable ** utf-8 string describing the most recent error encountered associated ** with dynamic libraries. */ static void jtDlError(sqlite3_vfs *pVfs, int nByte, char *zErrMsg){ g.pVfs->xDlError(g.pVfs, nByte, zErrMsg); } /* ** Return a pointer to the symbol zSymbol in the dynamic library pHandle. */ static void (*jtDlSym(sqlite3_vfs *pVfs, void *p, const char *zSym))(void){ return g.pVfs->xDlSym(g.pVfs, p, zSym); } /* ** Close the dynamic library handle pHandle. */ static void jtDlClose(sqlite3_vfs *pVfs, void *pHandle){ g.pVfs->xDlClose(g.pVfs, pHandle); } /* ** Populate the buffer pointed to by zBufOut with nByte bytes of ** random data. */ static int jtRandomness(sqlite3_vfs *pVfs, int nByte, char *zBufOut){ return sqlite3OsRandomness(g.pVfs, nByte, zBufOut); |
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643 644 645 646 647 648 649 650 651 652 653 654 | /* ** Return the current time as a Julian Day number in *pTimeOut. */ static int jtCurrentTime(sqlite3_vfs *pVfs, double *pTimeOut){ return sqlite3OsCurrentTime(g.pVfs, pTimeOut); } int jt_register(char *zWrap, int isDefault){ g.pVfs = sqlite3_vfs_find(zWrap); if( g.pVfs==0 ){ return SQLITE_ERROR; } | > > > > > > > > > > > | > > > | 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 | /* ** Return the current time as a Julian Day number in *pTimeOut. */ static int jtCurrentTime(sqlite3_vfs *pVfs, double *pTimeOut){ return sqlite3OsCurrentTime(g.pVfs, pTimeOut); } /************************************************************************** ** Start of public API. */ /* ** Configure the jt VFS as a wrapper around the VFS named by parameter ** zWrap. If the isDefault parameter is true, then the jt VFS is installed ** as the new default VFS for SQLite connections. If isDefault is not ** true, then the jt VFS is installed as non-default. In this case it ** is available via its name, "jt". */ int jt_register(char *zWrap, int isDefault){ g.pVfs = sqlite3_vfs_find(zWrap); if( g.pVfs==0 ){ return SQLITE_ERROR; } jt_vfs.szOsFile = sizeof(jt_file) + g.pVfs->szOsFile; sqlite3_vfs_register(&jt_vfs, isDefault); return SQLITE_OK; } /* ** Uninstall the jt VFS, if it is installed. */ void jt_unregister(){ sqlite3_vfs_unregister(&jt_vfs); } #endif |