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Overview
Comment: | Further simplifications to btree.c, especially the sqlite3BtreeKey() and sqlite3BtreeData() functions. New assert() statements added to verify that these routines are called correctly. (CVS 6917) |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | trunk |
Files: | files | file ages | folders |
SHA1: |
96cfd079528501f6f1e658ce8a5a4e3b |
User & Date: | drh 2009-07-22 00:35:24.000 |
Context
2009-07-22
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02:02 | Remove an ALWAYS() from a condition that can in fact be false under very obscure circumstances. (CVS 6918) (check-in: 3808322895 user: drh tags: trunk) | |
00:35 | Further simplifications to btree.c, especially the sqlite3BtreeKey() and sqlite3BtreeData() functions. New assert() statements added to verify that these routines are called correctly. (CVS 6917) (check-in: 96cfd07952 user: drh tags: trunk) | |
2009-07-21
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19:25 | Change getAndInitPage() (btree.c) to use only PagerAcquire(), not PagerLookup() and PagerAcquire(). (CVS 6916) (check-in: 0b41dfc066 user: danielk1977 tags: trunk) | |
Changes
Changes to src/btree.c.
1 2 3 4 5 6 7 8 9 10 11 | /* ** 2004 April 6 ** ** 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. ** ************************************************************************* | | | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | /* ** 2004 April 6 ** ** 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. ** ************************************************************************* ** $Id: btree.c,v 1.698 2009/07/22 00:35:24 drh Exp $ ** ** This file implements a external (disk-based) database using BTrees. ** See the header comment on "btreeInt.h" for additional information. ** Including a description of file format and an overview of operation. */ #include "btreeInt.h" |
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535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 | sqlite3BitvecDestroy(pBt->pHasContent); pBt->pHasContent = 0; } /* ** Save the current cursor position in the variables BtCursor.nKey ** and BtCursor.pKey. The cursor's state is set to CURSOR_REQUIRESEEK. */ static int saveCursorPosition(BtCursor *pCur){ int rc; assert( CURSOR_VALID==pCur->eState ); assert( 0==pCur->pKey ); assert( cursorHoldsMutex(pCur) ); rc = sqlite3BtreeKeySize(pCur, &pCur->nKey); | > > > | | 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 | sqlite3BitvecDestroy(pBt->pHasContent); pBt->pHasContent = 0; } /* ** Save the current cursor position in the variables BtCursor.nKey ** and BtCursor.pKey. The cursor's state is set to CURSOR_REQUIRESEEK. ** ** The caller must ensure that the cursor is valid (has eState==CURSOR_VALID) ** prior to calling this routine. */ static int saveCursorPosition(BtCursor *pCur){ int rc; assert( CURSOR_VALID==pCur->eState ); assert( 0==pCur->pKey ); assert( cursorHoldsMutex(pCur) ); rc = sqlite3BtreeKeySize(pCur, &pCur->nKey); assert( rc==SQLITE_OK ); /* KeySize() cannot fail */ /* If this is an intKey table, then the above call to BtreeKeySize() ** stores the integer key in pCur->nKey. In this case this value is ** all that is required. Otherwise, if pCur is not open on an intKey ** table, then malloc space for and store the pCur->nKey bytes of key ** data. */ |
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2703 2704 2705 2706 2707 2708 2709 | ** return SQLITE_OK. If there is no work to do (and therefore no ** point in calling this function again), return SQLITE_DONE. ** ** More specificly, this function attempts to re-organize the ** database so that the last page of the file currently in use ** is no longer in use. ** | | | > > > | 2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 | ** return SQLITE_OK. If there is no work to do (and therefore no ** point in calling this function again), return SQLITE_DONE. ** ** More specificly, this function attempts to re-organize the ** database so that the last page of the file currently in use ** is no longer in use. ** ** If the nFin parameter is non-zero, this function assumes ** that the caller will keep calling incrVacuumStep() until ** it returns SQLITE_DONE or an error, and that nFin is the ** number of pages the database file will contain after this ** process is complete. If nFin is zero, it is assumed that ** incrVacuumStep() will be called a finite amount of times ** which may or may not empty the freelist. A full autovacuum ** has nFin>0. A "PRAGMA incremental_vacuum" has nFin==0. */ static int incrVacuumStep(BtShared *pBt, Pgno nFin, Pgno iLastPg){ Pgno nFreeList; /* Number of pages still on the free-list */ assert( sqlite3_mutex_held(pBt->mutex) ); assert( iLastPg>nFin ); |
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2851 2852 2853 2854 2855 2856 2857 | Pager *pPager = pBt->pPager; VVA_ONLY( int nRef = sqlite3PagerRefcount(pPager) ); assert( sqlite3_mutex_held(pBt->mutex) ); invalidateAllOverflowCache(pBt); assert(pBt->autoVacuum); if( !pBt->incrVacuum ){ | | | | 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 | Pager *pPager = pBt->pPager; VVA_ONLY( int nRef = sqlite3PagerRefcount(pPager) ); assert( sqlite3_mutex_held(pBt->mutex) ); invalidateAllOverflowCache(pBt); assert(pBt->autoVacuum); if( !pBt->incrVacuum ){ Pgno nFin; /* Number of pages in database after autovacuuming */ Pgno nFree; /* Number of pages on the freelist initially */ Pgno nPtrmap; /* Number of PtrMap pages to be freed */ Pgno iFree; /* The next page to be freed */ int nEntry; /* Number of entries on one ptrmap page */ Pgno nOrig; /* Database size before freeing */ nOrig = pagerPagecount(pBt); if( PTRMAP_ISPAGE(pBt, nOrig) || nOrig==PENDING_BYTE_PAGE(pBt) ){ |
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3437 3438 3439 3440 3441 3442 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452 | btreeParseCell(pCur->apPage[iPage],pCur->aiIdx[iPage],&pCur->info); \ pCur->validNKey = 1; \ }else{ \ assertCellInfo(pCur); \ } #endif /* _MSC_VER */ /* ** Set *pSize to the size of the buffer needed to hold the value of ** the key for the current entry. If the cursor is not pointing ** to a valid entry, *pSize is set to 0. ** ** For a table with the INTKEY flag set, this routine returns the key ** itself, not the number of bytes in the key. */ int sqlite3BtreeKeySize(BtCursor *pCur, i64 *pSize){ | > > > > > > > > > > > > > > > < < < < | | | | | | | < | | > > > > > | < < > > < < < < | < < < < | | < < | | 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452 3453 3454 3455 3456 3457 3458 3459 3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474 3475 3476 3477 3478 3479 3480 3481 3482 3483 3484 3485 3486 3487 3488 3489 3490 3491 3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 3502 3503 3504 3505 3506 3507 3508 3509 | btreeParseCell(pCur->apPage[iPage],pCur->aiIdx[iPage],&pCur->info); \ pCur->validNKey = 1; \ }else{ \ assertCellInfo(pCur); \ } #endif /* _MSC_VER */ #ifndef NDEBUG /* The next routine used only within assert() statements */ /* ** Return true if the given BtCursor is valid. A valid cursor is one ** that is currently pointing to a row in a (non-empty) table. ** This is a verification routine is used only within assert() statements. */ int sqlite3BtreeCursorIsValid(BtCursor *pCur){ return pCur && pCur->eState==CURSOR_VALID; } #endif /* NDEBUG */ /* ** Set *pSize to the size of the buffer needed to hold the value of ** the key for the current entry. If the cursor is not pointing ** to a valid entry, *pSize is set to 0. ** ** For a table with the INTKEY flag set, this routine returns the key ** itself, not the number of bytes in the key. ** ** The caller must position the cursor prior to invoking this routine. ** ** This routine cannot fail. It always returns SQLITE_OK. */ int sqlite3BtreeKeySize(BtCursor *pCur, i64 *pSize){ assert( cursorHoldsMutex(pCur) ); assert( pCur->eState==CURSOR_INVALID || pCur->eState==CURSOR_VALID ); if( pCur->eState!=CURSOR_VALID ){ *pSize = 0; }else{ getCellInfo(pCur); *pSize = pCur->info.nKey; } return SQLITE_OK; } /* ** Set *pSize to the number of bytes of data in the entry the ** cursor currently points to. ** ** The caller must guarantee that the cursor is pointing to a non-NULL ** valid entry. In other words, the calling procedure must guarantee ** that the cursor has Cursor.eState==CURSOR_VALID. ** ** Failure is not possible. This function always returns SQLITE_OK. ** It might just as well be a procedure (returning void) but we continue ** to return an integer result code for historical reasons. */ int sqlite3BtreeDataSize(BtCursor *pCur, u32 *pSize){ assert( cursorHoldsMutex(pCur) ); assert( pCur->eState==CURSOR_VALID ); getCellInfo(pCur); *pSize = pCur->info.nData; return SQLITE_OK; } /* ** Given the page number of an overflow page in the database (parameter ** ovfl), this function finds the page number of the next page in the ** linked list of overflow pages. If possible, it uses the auto-vacuum ** pointer-map data instead of reading the content of page ovfl to do so. |
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Changes to src/btree.h.
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9 10 11 12 13 14 15 | ** May you share freely, never taking more than you give. ** ************************************************************************* ** This header file defines the interface that the sqlite B-Tree file ** subsystem. See comments in the source code for a detailed description ** of what each interface routine does. ** | | | 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 | ** May you share freely, never taking more than you give. ** ************************************************************************* ** This header file defines the interface that the sqlite B-Tree file ** subsystem. See comments in the source code for a detailed description ** of what each interface routine does. ** ** @(#) $Id: btree.h,v 1.120 2009/07/22 00:35:24 drh Exp $ */ #ifndef _BTREE_H_ #define _BTREE_H_ /* TODO: This definition is just included so other modules compile. It ** needs to be revisited. */ |
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180 181 182 183 184 185 186 187 188 189 190 191 192 193 | char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*); struct Pager *sqlite3BtreePager(Btree*); int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*); void sqlite3BtreeCacheOverflow(BtCursor *); void sqlite3BtreeClearCursor(BtCursor *); #ifndef SQLITE_OMIT_BTREECOUNT int sqlite3BtreeCount(BtCursor *, i64 *); #endif #ifdef SQLITE_TEST int sqlite3BtreeCursorInfo(BtCursor*, int*, int); | > > > > | 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 | char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*); struct Pager *sqlite3BtreePager(Btree*); int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*); void sqlite3BtreeCacheOverflow(BtCursor *); void sqlite3BtreeClearCursor(BtCursor *); #ifndef NDEBUG int sqlite3BtreeCursorIsValid(BtCursor*); #endif #ifndef SQLITE_OMIT_BTREECOUNT int sqlite3BtreeCount(BtCursor *, i64 *); #endif #ifdef SQLITE_TEST int sqlite3BtreeCursorInfo(BtCursor*, int*, int); |
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Changes to src/vdbe.c.
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39 40 41 42 43 44 45 | ** ** Various scripts scan this source file in order to generate HTML ** documentation, headers files, or other derived files. The formatting ** of the code in this file is, therefore, important. See other comments ** in this file for details. If in doubt, do not deviate from existing ** commenting and indentation practices when changing or adding code. ** | | | 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 | ** ** Various scripts scan this source file in order to generate HTML ** documentation, headers files, or other derived files. The formatting ** of the code in this file is, therefore, important. See other comments ** in this file for details. If in doubt, do not deviate from existing ** commenting and indentation practices when changing or adding code. ** ** $Id: vdbe.c,v 1.873 2009/07/22 00:35:24 drh Exp $ */ #include "sqliteInt.h" #include "vdbeInt.h" /* ** The following global variable is incremented every time a cursor ** moves, either by the OP_SeekXX, OP_Next, or OP_Prev opcodes. The test |
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2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 | if( rc ) goto abort_due_to_error; if( pC->nullRow ){ payloadSize = 0; }else if( pC->cacheStatus==p->cacheCtr ){ payloadSize = pC->payloadSize; zRec = (char*)pC->aRow; }else if( pC->isIndex ){ rc = sqlite3BtreeKeySize(pCrsr, &payloadSize64); assert( rc==SQLITE_OK ); /* True because of CursorMoveto() call above */ /* sqlite3BtreeParseCellPtr() uses getVarint32() to extract the ** payload size, so it is impossible for payloadSize64 to be ** larger than 32 bits. */ assert( (payloadSize64 & SQLITE_MAX_U32)==(u64)payloadSize64 ); payloadSize = (u32)payloadSize64; }else{ rc = sqlite3BtreeDataSize(pCrsr, &payloadSize); | > > | | 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 | if( rc ) goto abort_due_to_error; if( pC->nullRow ){ payloadSize = 0; }else if( pC->cacheStatus==p->cacheCtr ){ payloadSize = pC->payloadSize; zRec = (char*)pC->aRow; }else if( pC->isIndex ){ assert( sqlite3BtreeCursorIsValid(pCrsr) ); rc = sqlite3BtreeKeySize(pCrsr, &payloadSize64); assert( rc==SQLITE_OK ); /* True because of CursorMoveto() call above */ /* sqlite3BtreeParseCellPtr() uses getVarint32() to extract the ** payload size, so it is impossible for payloadSize64 to be ** larger than 32 bits. */ assert( (payloadSize64 & SQLITE_MAX_U32)==(u64)payloadSize64 ); payloadSize = (u32)payloadSize64; }else{ assert( sqlite3BtreeCursorIsValid(pCrsr) ); rc = sqlite3BtreeDataSize(pCrsr, &payloadSize); assert( rc==SQLITE_OK ); /* DataSize() cannot fail */ } }else if( pC->pseudoTable ){ /* The record is the sole entry of a pseudo-table */ payloadSize = pC->nData; zRec = pC->pData; pC->cacheStatus = CACHE_STALE; assert( payloadSize==0 || zRec!=0 ); |
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3589 3590 3591 3592 3593 3594 3595 3596 3597 3598 3599 3600 3601 3602 | rc = sqlite3BtreeLast(pC->pCursor, &res); if( rc!=SQLITE_OK ){ goto abort_due_to_error; } if( res ){ v = 1; }else{ rc = sqlite3BtreeKeySize(pC->pCursor, &v); assert( rc==SQLITE_OK ); /* Cannot fail following BtreeLast() */ if( v==MAX_ROWID ){ pC->useRandomRowid = 1; }else{ v++; } | > | 3591 3592 3593 3594 3595 3596 3597 3598 3599 3600 3601 3602 3603 3604 3605 | rc = sqlite3BtreeLast(pC->pCursor, &res); if( rc!=SQLITE_OK ){ goto abort_due_to_error; } if( res ){ v = 1; }else{ assert( sqlite3BtreeCursorIsValid(pC->pCursor) ); rc = sqlite3BtreeKeySize(pC->pCursor, &v); assert( rc==SQLITE_OK ); /* Cannot fail following BtreeLast() */ if( v==MAX_ROWID ){ pC->useRandomRowid = 1; }else{ v++; } |
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3875 3876 3877 3878 3879 3880 3881 3882 3883 3884 3885 3886 3887 3888 3889 3890 3891 3892 3893 3894 3895 3896 3897 3898 3899 3900 3901 | assert( pC->isTable || pOp->opcode==OP_RowKey ); assert( pC->isIndex || pOp->opcode==OP_RowData ); assert( pC!=0 ); assert( pC->nullRow==0 ); assert( pC->pseudoTable==0 ); assert( pC->pCursor!=0 ); pCrsr = pC->pCursor; /* The OP_RowKey and OP_RowData opcodes always follow OP_NotExists or ** OP_Rewind/Op_Next with no intervening instructions that might invalidate ** the cursor. Hence the following sqlite3VdbeCursorMoveto() call is always ** a no-op and can never fail. But we leave it in place as a safety. */ assert( pC->deferredMoveto==0 ); rc = sqlite3VdbeCursorMoveto(pC); if( NEVER(rc!=SQLITE_OK) ) goto abort_due_to_error; if( pC->isIndex ){ assert( !pC->isTable ); rc = sqlite3BtreeKeySize(pCrsr, &n64); assert( rc==SQLITE_OK ); /* True because of CursorMoveto() call above */ if( n64>db->aLimit[SQLITE_LIMIT_LENGTH] ){ goto too_big; } n = (u32)n64; }else{ rc = sqlite3BtreeDataSize(pCrsr, &n); | > | | 3878 3879 3880 3881 3882 3883 3884 3885 3886 3887 3888 3889 3890 3891 3892 3893 3894 3895 3896 3897 3898 3899 3900 3901 3902 3903 3904 3905 3906 3907 3908 3909 3910 3911 3912 3913 | assert( pC->isTable || pOp->opcode==OP_RowKey ); assert( pC->isIndex || pOp->opcode==OP_RowData ); assert( pC!=0 ); assert( pC->nullRow==0 ); assert( pC->pseudoTable==0 ); assert( pC->pCursor!=0 ); pCrsr = pC->pCursor; assert( sqlite3BtreeCursorIsValid(pCrsr) ); /* The OP_RowKey and OP_RowData opcodes always follow OP_NotExists or ** OP_Rewind/Op_Next with no intervening instructions that might invalidate ** the cursor. Hence the following sqlite3VdbeCursorMoveto() call is always ** a no-op and can never fail. But we leave it in place as a safety. */ assert( pC->deferredMoveto==0 ); rc = sqlite3VdbeCursorMoveto(pC); if( NEVER(rc!=SQLITE_OK) ) goto abort_due_to_error; if( pC->isIndex ){ assert( !pC->isTable ); rc = sqlite3BtreeKeySize(pCrsr, &n64); assert( rc==SQLITE_OK ); /* True because of CursorMoveto() call above */ if( n64>db->aLimit[SQLITE_LIMIT_LENGTH] ){ goto too_big; } n = (u32)n64; }else{ rc = sqlite3BtreeDataSize(pCrsr, &n); assert( rc==SQLITE_OK ); /* DataSize() cannot fail */ if( n>(u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){ goto too_big; } } if( sqlite3VdbeMemGrow(pOut, n, 0) ){ goto no_mem; } |
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Changes to src/vdbeaux.c.
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10 11 12 13 14 15 16 | ** ************************************************************************* ** This file contains code used for creating, destroying, and populating ** a VDBE (or an "sqlite3_stmt" as it is known to the outside world.) Prior ** to version 2.8.7, all this code was combined into the vdbe.c source file. ** But that file was getting too big so this subroutines were split out. ** | | | 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 | ** ************************************************************************* ** This file contains code used for creating, destroying, and populating ** a VDBE (or an "sqlite3_stmt" as it is known to the outside world.) Prior ** to version 2.8.7, all this code was combined into the vdbe.c source file. ** But that file was getting too big so this subroutines were split out. ** ** $Id: vdbeaux.c,v 1.477 2009/07/22 00:35:24 drh Exp $ */ #include "sqliteInt.h" #include "vdbeInt.h" /* |
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2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 | Mem m, v; /* Get the size of the index entry. Only indices entries of less ** than 2GiB are support - anything large must be database corruption. ** Any corruption is detected in sqlite3BtreeParseCellPtr(), though, so ** this code can safely assume that nCellKey is 32-bits */ rc = sqlite3BtreeKeySize(pCur, &nCellKey); assert( rc==SQLITE_OK ); /* pCur is always valid so KeySize cannot fail */ assert( (nCellKey & SQLITE_MAX_U32)==(u64)nCellKey ); /* Read in the complete content of the index entry */ m.flags = 0; m.db = db; | > | 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 | Mem m, v; /* Get the size of the index entry. Only indices entries of less ** than 2GiB are support - anything large must be database corruption. ** Any corruption is detected in sqlite3BtreeParseCellPtr(), though, so ** this code can safely assume that nCellKey is 32-bits */ assert( sqlite3BtreeCursorIsValid(pCur) ); rc = sqlite3BtreeKeySize(pCur, &nCellKey); assert( rc==SQLITE_OK ); /* pCur is always valid so KeySize cannot fail */ assert( (nCellKey & SQLITE_MAX_U32)==(u64)nCellKey ); /* Read in the complete content of the index entry */ m.flags = 0; m.db = db; |
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2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 | int *res /* Write the comparison result here */ ){ i64 nCellKey = 0; int rc; BtCursor *pCur = pC->pCursor; Mem m; rc = sqlite3BtreeKeySize(pCur, &nCellKey); assert( rc==SQLITE_OK ); /* pCur is always valid so KeySize cannot fail */ /* nCellKey will always be between 0 and 0xffffffff because of the say ** that btreeParseCellPtr() and sqlite3GetVarint32() are implemented */ if( nCellKey<=0 || nCellKey>0x7fffffff ){ *res = 0; return SQLITE_CORRUPT; | > | 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 | int *res /* Write the comparison result here */ ){ i64 nCellKey = 0; int rc; BtCursor *pCur = pC->pCursor; Mem m; assert( sqlite3BtreeCursorIsValid(pCur) ); rc = sqlite3BtreeKeySize(pCur, &nCellKey); assert( rc==SQLITE_OK ); /* pCur is always valid so KeySize cannot fail */ /* nCellKey will always be between 0 and 0xffffffff because of the say ** that btreeParseCellPtr() and sqlite3GetVarint32() are implemented */ if( nCellKey<=0 || nCellKey>0x7fffffff ){ *res = 0; return SQLITE_CORRUPT; |
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