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Overview
Comment: | Experimental change to the xShmXXX parts of the VFS interface. |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | experimental |
Files: | files | file ages | folders |
SHA1: |
ca68472db01c14a899892007d1cbaff5 |
User & Date: | dan 2010-06-11 19:04:21.000 |
Context
2010-06-12
| ||
12:02 | Fix some problems with handling IO errors on the experimental branch. (check-in: eade8bc238 user: dan tags: experimental) | |
2010-06-11
| ||
19:04 | Experimental change to the xShmXXX parts of the VFS interface. (check-in: ca68472db0 user: dan tags: experimental) | |
17:01 | Refactor and simplify the logic used to change journalmode. (check-in: 95cc3f6fde user: drh tags: trunk) | |
Changes
Changes to src/os.c.
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115 116 117 118 119 120 121 122 123 124 125 126 127 128 | } void sqlite3OsShmBarrier(sqlite3_file *id){ id->pMethods->xShmBarrier(id); } int sqlite3OsShmClose(sqlite3_file *id, int deleteFlag){ return id->pMethods->xShmClose(id, deleteFlag); } /* ** The next group of routines are convenience wrappers around the ** VFS methods. */ int sqlite3OsOpen( sqlite3_vfs *pVfs, | > > > > > > > > > | 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 | } void sqlite3OsShmBarrier(sqlite3_file *id){ id->pMethods->xShmBarrier(id); } int sqlite3OsShmClose(sqlite3_file *id, int deleteFlag){ return id->pMethods->xShmClose(id, deleteFlag); } int sqlite3OsShmPage( sqlite3_file *id, int iPage, int pgsz, int isWrite, void volatile **pp ){ return id->pMethods->xShmPage(id, iPage, pgsz, isWrite, pp); } /* ** The next group of routines are convenience wrappers around the ** VFS methods. */ int sqlite3OsOpen( sqlite3_vfs *pVfs, |
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Changes to src/os.h.
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250 251 252 253 254 255 256 257 258 259 260 261 262 263 | int sqlite3OsShmOpen(sqlite3_file *id); int sqlite3OsShmSize(sqlite3_file *id, int, int*); int sqlite3OsShmGet(sqlite3_file *id, int, int*, void volatile**); int sqlite3OsShmRelease(sqlite3_file *id); int sqlite3OsShmLock(sqlite3_file *id, int, int, int); void sqlite3OsShmBarrier(sqlite3_file *id); int sqlite3OsShmClose(sqlite3_file *id, int); /* ** Functions for accessing sqlite3_vfs methods */ int sqlite3OsOpen(sqlite3_vfs *, const char *, sqlite3_file*, int, int *); int sqlite3OsDelete(sqlite3_vfs *, const char *, int); int sqlite3OsAccess(sqlite3_vfs *, const char *, int, int *pResOut); | > | 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 | int sqlite3OsShmOpen(sqlite3_file *id); int sqlite3OsShmSize(sqlite3_file *id, int, int*); int sqlite3OsShmGet(sqlite3_file *id, int, int*, void volatile**); int sqlite3OsShmRelease(sqlite3_file *id); int sqlite3OsShmLock(sqlite3_file *id, int, int, int); void sqlite3OsShmBarrier(sqlite3_file *id); int sqlite3OsShmClose(sqlite3_file *id, int); int sqlite3OsShmPage(sqlite3_file *,int,int,int,void volatile **); /* ** Functions for accessing sqlite3_vfs methods */ int sqlite3OsOpen(sqlite3_vfs *, const char *, sqlite3_file*, int, int *); int sqlite3OsDelete(sqlite3_vfs *, const char *, int); int sqlite3OsAccess(sqlite3_vfs *, const char *, int, int *pResOut); |
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Changes to src/os_unix.c.
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3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152 | */ struct unixShmNode { unixInodeInfo *pInode; /* unixInodeInfo that owns this SHM node */ sqlite3_mutex *mutex; /* Mutex to access this object */ sqlite3_mutex *mutexBuf; /* Mutex to access zBuf[] */ char *zFilename; /* Name of the mmapped file */ int h; /* Open file descriptor */ int szMap; /* Size of the mapping into memory */ char *pMMapBuf; /* Where currently mmapped(). NULL if unmapped */ int nRef; /* Number of unixShm objects pointing to this */ unixShm *pFirst; /* All unixShm objects pointing to this */ #ifdef SQLITE_DEBUG u8 exclMask; /* Mask of exclusive locks held */ u8 sharedMask; /* Mask of shared locks held */ u8 nextShmId; /* Next available unixShm.id value */ #endif | > > > > > > | 3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156 3157 3158 | */ struct unixShmNode { unixInodeInfo *pInode; /* unixInodeInfo that owns this SHM node */ sqlite3_mutex *mutex; /* Mutex to access this object */ sqlite3_mutex *mutexBuf; /* Mutex to access zBuf[] */ char *zFilename; /* Name of the mmapped file */ int h; /* Open file descriptor */ int szMap; /* Size of the mapping into memory */ char *pMMapBuf; /* Where currently mmapped(). NULL if unmapped */ int pgsz; /* Size of shared-memory pages */ int nPage; /* Size of array apPage */ char **apPage; /* Array of mapped shared-memory pages */ int nRef; /* Number of unixShm objects pointing to this */ unixShm *pFirst; /* All unixShm objects pointing to this */ #ifdef SQLITE_DEBUG u8 exclMask; /* Mask of exclusive locks held */ u8 sharedMask; /* Mask of shared locks held */ u8 nextShmId; /* Next available unixShm.id value */ #endif |
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3262 3263 3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 | ** This is not a VFS shared-memory method; it is a utility function called ** by VFS shared-memory methods. */ static void unixShmPurge(unixFile *pFd){ unixShmNode *p = pFd->pInode->pShmNode; assert( unixMutexHeld() ); if( p && p->nRef==0 ){ assert( p->pInode==pFd->pInode ); if( p->mutex ) sqlite3_mutex_free(p->mutex); if( p->mutexBuf ) sqlite3_mutex_free(p->mutexBuf); if( p->pMMapBuf ) munmap(p->pMMapBuf, p->szMap); if( p->h>=0 ) close(p->h); p->pInode->pShmNode = 0; sqlite3_free(p); } } /* Forward reference */ | > > > > > | 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 | ** This is not a VFS shared-memory method; it is a utility function called ** by VFS shared-memory methods. */ static void unixShmPurge(unixFile *pFd){ unixShmNode *p = pFd->pInode->pShmNode; assert( unixMutexHeld() ); if( p && p->nRef==0 ){ int i; assert( p->pInode==pFd->pInode ); if( p->mutex ) sqlite3_mutex_free(p->mutex); if( p->mutexBuf ) sqlite3_mutex_free(p->mutexBuf); if( p->pMMapBuf ) munmap(p->pMMapBuf, p->szMap); for(i=0; i<p->nPage; i++){ munmap(p->apPage[i], p->pgsz); } sqlite3_free(p->apPage); if( p->h>=0 ) close(p->h); p->pInode->pShmNode = 0; sqlite3_free(p); } } /* Forward reference */ |
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3702 3703 3704 3705 3706 3707 3708 3709 3710 3711 3712 3713 3714 3715 3716 3717 3718 3719 3720 3721 3722 3723 3724 | static void unixShmBarrier( sqlite3_file *fd /* Database file holding the shared memory */ ){ unixEnterMutex(); unixLeaveMutex(); } #else # define unixShmOpen 0 # define unixShmSize 0 # define unixShmGet 0 # define unixShmRelease 0 # define unixShmLock 0 # define unixShmBarrier 0 # define unixShmClose 0 #endif /* #ifndef SQLITE_OMIT_WAL */ /* ** Here ends the implementation of all sqlite3_file methods. ** ********************** End sqlite3_file Methods ******************************* ******************************************************************************/ | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 3713 3714 3715 3716 3717 3718 3719 3720 3721 3722 3723 3724 3725 3726 3727 3728 3729 3730 3731 3732 3733 3734 3735 3736 3737 3738 3739 3740 3741 3742 3743 3744 3745 3746 3747 3748 3749 3750 3751 3752 3753 3754 3755 3756 3757 3758 3759 3760 3761 3762 3763 3764 3765 3766 3767 3768 3769 3770 3771 3772 3773 3774 3775 3776 3777 3778 3779 3780 3781 3782 3783 3784 3785 3786 3787 3788 3789 3790 3791 3792 3793 3794 3795 3796 3797 3798 3799 3800 3801 | static void unixShmBarrier( sqlite3_file *fd /* Database file holding the shared memory */ ){ unixEnterMutex(); unixLeaveMutex(); } static int unixShmPage( sqlite3_file *fd, /* Handle open on database file */ int iPage, /* Page to retrieve */ int pgsz, /* Size of pages */ int isWrite, /* True to extend file if necessary */ void volatile **pp /* OUT: Mapped memory */ ){ unixFile *pDbFd = (unixFile*)fd; unixShm *p = pDbFd->pShm; unixShmNode *pShmNode = p->pShmNode; int rc = SQLITE_OK; assert( p->hasMutexBuf==0 ); sqlite3_mutex_enter(pShmNode->mutexBuf); assert( pgsz==pShmNode->pgsz || pShmNode->nPage==0 ); if( pShmNode->nPage<=iPage ){ char **apNew; /* New apPage[] array */ int nByte = (iPage+1)*pgsz; /* Minimum required file size */ struct stat sStat; pShmNode->pgsz = pgsz; /* Make sure the underlying file is large enough (or fail) */ if( fstat(pShmNode->h, &sStat) ){ rc = SQLITE_IOERR_SHMSIZE; goto shmpage_out; }else if( sStat.st_size<nByte ){ if( !isWrite ) goto shmpage_out; if( ftruncate(pShmNode->h, nByte) ){ rc = SQLITE_IOERR_SHMSIZE; goto shmpage_out; } } apNew = (char**)sqlite3_realloc(pShmNode->apPage, (iPage+1)*sizeof(char *)); if( !apNew ){ rc = SQLITE_IOERR_NOMEM; goto shmpage_out; } pShmNode->apPage = apNew; while(pShmNode->nPage<=iPage){ void *pMem = mmap( 0, pgsz, PROT_READ|PROT_WRITE, MAP_SHARED, pShmNode->h, iPage*pgsz ); if( pMem==MAP_FAILED ){ assert(0); rc = SQLITE_IOERR; goto shmpage_out; } pShmNode->apPage[pShmNode->nPage] = pMem; pShmNode->nPage++; } } shmpage_out: if( pShmNode->nPage>iPage ){ *pp = pShmNode->apPage[iPage]; }else{ *pp = 0; } sqlite3_mutex_leave(pShmNode->mutexBuf); return rc; } #else # define unixShmOpen 0 # define unixShmSize 0 # define unixShmGet 0 # define unixShmRelease 0 # define unixShmLock 0 # define unixShmBarrier 0 # define unixShmClose 0 # define unixShmPage 0 #endif /* #ifndef SQLITE_OMIT_WAL */ /* ** Here ends the implementation of all sqlite3_file methods. ** ********************** End sqlite3_file Methods ******************************* ******************************************************************************/ |
︙ | ︙ | |||
3774 3775 3776 3777 3778 3779 3780 | unixDeviceCharacteristics, /* xDeviceCapabilities */ \ unixShmOpen, /* xShmOpen */ \ unixShmSize, /* xShmSize */ \ unixShmGet, /* xShmGet */ \ unixShmRelease, /* xShmRelease */ \ unixShmLock, /* xShmLock */ \ unixShmBarrier, /* xShmBarrier */ \ | | > | 3851 3852 3853 3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866 | unixDeviceCharacteristics, /* xDeviceCapabilities */ \ unixShmOpen, /* xShmOpen */ \ unixShmSize, /* xShmSize */ \ unixShmGet, /* xShmGet */ \ unixShmRelease, /* xShmRelease */ \ unixShmLock, /* xShmLock */ \ unixShmBarrier, /* xShmBarrier */ \ unixShmClose, /* xShmClose */ \ unixShmPage /* xShmPage */ \ }; \ static const sqlite3_io_methods *FINDER##Impl(const char *z, unixFile *p){ \ UNUSED_PARAMETER(z); UNUSED_PARAMETER(p); \ return &METHOD; \ } \ static const sqlite3_io_methods *(*const FINDER)(const char*,unixFile *p) \ = FINDER##Impl; |
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Changes to src/sqlite.h.in.
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662 663 664 665 666 667 668 669 670 671 672 673 674 675 | int (*xShmOpen)(sqlite3_file*); int (*xShmSize)(sqlite3_file*, int reqSize, int *pNewSize); int (*xShmGet)(sqlite3_file*, int reqSize, int *pSize, void volatile**); int (*xShmRelease)(sqlite3_file*); int (*xShmLock)(sqlite3_file*, int offset, int n, int flags); void (*xShmBarrier)(sqlite3_file*); int (*xShmClose)(sqlite3_file*, int deleteFlag); /* Methods above are valid for version 2 */ /* Additional methods may be added in future releases */ }; /* ** CAPI3REF: Standard File Control Opcodes ** | > | 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 | int (*xShmOpen)(sqlite3_file*); int (*xShmSize)(sqlite3_file*, int reqSize, int *pNewSize); int (*xShmGet)(sqlite3_file*, int reqSize, int *pSize, void volatile**); int (*xShmRelease)(sqlite3_file*); int (*xShmLock)(sqlite3_file*, int offset, int n, int flags); void (*xShmBarrier)(sqlite3_file*); int (*xShmClose)(sqlite3_file*, int deleteFlag); int (*xShmPage)(sqlite3_file*, int iPage, int pgsz, int, void volatile**); /* Methods above are valid for version 2 */ /* Additional methods may be added in future releases */ }; /* ** CAPI3REF: Standard File Control Opcodes ** |
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Changes to src/test_devsym.c.
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53 54 55 56 57 58 59 60 61 62 63 64 65 66 | static int devsymShmOpen(sqlite3_file*); static int devsymShmSize(sqlite3_file*,int,int*); static int devsymShmGet(sqlite3_file*,int,int*,volatile void**); static int devsymShmRelease(sqlite3_file*); static int devsymShmLock(sqlite3_file*,int,int,int); static void devsymShmBarrier(sqlite3_file*); static int devsymShmClose(sqlite3_file*,int); /* ** Method declarations for devsym_vfs. */ static int devsymOpen(sqlite3_vfs*, const char *, sqlite3_file*, int , int *); static int devsymDelete(sqlite3_vfs*, const char *zName, int syncDir); static int devsymAccess(sqlite3_vfs*, const char *zName, int flags, int *); | > | 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 | static int devsymShmOpen(sqlite3_file*); static int devsymShmSize(sqlite3_file*,int,int*); static int devsymShmGet(sqlite3_file*,int,int*,volatile void**); static int devsymShmRelease(sqlite3_file*); static int devsymShmLock(sqlite3_file*,int,int,int); static void devsymShmBarrier(sqlite3_file*); static int devsymShmClose(sqlite3_file*,int); static int devsymShmPage(sqlite3_file*,int,int,int, void volatile **); /* ** Method declarations for devsym_vfs. */ static int devsymOpen(sqlite3_vfs*, const char *, sqlite3_file*, int , int *); static int devsymDelete(sqlite3_vfs*, const char *zName, int syncDir); static int devsymAccess(sqlite3_vfs*, const char *zName, int flags, int *); |
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121 122 123 124 125 126 127 | devsymDeviceCharacteristics, /* xDeviceCharacteristics */ devsymShmOpen, /* xShmOpen */ devsymShmSize, /* xShmSize */ devsymShmGet, /* xShmGet */ devsymShmRelease, /* xShmRelease */ devsymShmLock, /* xShmLock */ devsymShmBarrier, /* xShmBarrier */ | | > | 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 | devsymDeviceCharacteristics, /* xDeviceCharacteristics */ devsymShmOpen, /* xShmOpen */ devsymShmSize, /* xShmSize */ devsymShmGet, /* xShmGet */ devsymShmRelease, /* xShmRelease */ devsymShmLock, /* xShmLock */ devsymShmBarrier, /* xShmBarrier */ devsymShmClose, /* xShmClose */ devsymShmPage /* xShmPage */ }; struct DevsymGlobal { sqlite3_vfs *pVfs; int iDeviceChar; int iSectorSize; }; |
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271 272 273 274 275 276 277 278 279 280 281 282 283 284 | devsym_file *p = (devsym_file *)pFile; sqlite3OsShmBarrier(p->pReal); } static int devsymShmClose(sqlite3_file *pFile, int delFlag){ devsym_file *p = (devsym_file *)pFile; return sqlite3OsShmClose(p->pReal, delFlag); } /* ** Open an devsym file handle. */ static int devsymOpen( | > > > > > > > > > > | 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 | devsym_file *p = (devsym_file *)pFile; sqlite3OsShmBarrier(p->pReal); } static int devsymShmClose(sqlite3_file *pFile, int delFlag){ devsym_file *p = (devsym_file *)pFile; return sqlite3OsShmClose(p->pReal, delFlag); } static int devsymShmPage( sqlite3_file *pFile, int iPage, int pgsz, int isWrite, void volatile **pp ){ devsym_file *p = (devsym_file *)pFile; return sqlite3OsShmPage(p->pReal, iPage, pgsz, isWrite, pp); } /* ** Open an devsym file handle. */ static int devsymOpen( |
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Changes to src/test_vfs.c.
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71 72 73 74 75 76 77 78 | #define TESTVFS_SHMOPEN_MASK 0x00000001 #define TESTVFS_SHMSIZE_MASK 0x00000002 #define TESTVFS_SHMGET_MASK 0x00000004 #define TESTVFS_SHMRELEASE_MASK 0x00000008 #define TESTVFS_SHMLOCK_MASK 0x00000010 #define TESTVFS_SHMBARRIER_MASK 0x00000020 #define TESTVFS_SHMCLOSE_MASK 0x00000040 | > | | | > > > | | | 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 | #define TESTVFS_SHMOPEN_MASK 0x00000001 #define TESTVFS_SHMSIZE_MASK 0x00000002 #define TESTVFS_SHMGET_MASK 0x00000004 #define TESTVFS_SHMRELEASE_MASK 0x00000008 #define TESTVFS_SHMLOCK_MASK 0x00000010 #define TESTVFS_SHMBARRIER_MASK 0x00000020 #define TESTVFS_SHMCLOSE_MASK 0x00000040 #define TESTVFS_SHMPAGE_MASK 0x00000080 #define TESTVFS_OPEN_MASK 0x00000100 #define TESTVFS_SYNC_MASK 0x00000200 #define TESTVFS_ALL_MASK 0x000003FF #define TESTVFS_MAX_PAGES 256 /* ** A shared-memory buffer. There is one of these objects for each shared ** memory region opened by clients. If two clients open the same file, ** there are two TestvfsFile structures but only one TestvfsBuffer structure. */ struct TestvfsBuffer { char *zFile; /* Associated file name */ int pgsz; /* Page size */ u8 *aPage[TESTVFS_MAX_PAGES]; /* Array of ckalloc'd pages */ TestvfsFile *pFile; /* List of open handles */ TestvfsBuffer *pNext; /* Next in linked list of all buffers */ }; #define PARENTVFS(x) (((Testvfs *)((x)->pAppData))->pParent) |
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135 136 137 138 139 140 141 142 143 144 145 146 147 148 | static int tvfsShmOpen(sqlite3_file*); static int tvfsShmSize(sqlite3_file*, int , int *); static int tvfsShmGet(sqlite3_file*, int , int *, volatile void **); static int tvfsShmRelease(sqlite3_file*); static int tvfsShmLock(sqlite3_file*, int , int, int); static void tvfsShmBarrier(sqlite3_file*); static int tvfsShmClose(sqlite3_file*, int); static sqlite3_io_methods tvfs_io_methods = { 2, /* iVersion */ tvfsClose, /* xClose */ tvfsRead, /* xRead */ tvfsWrite, /* xWrite */ tvfsTruncate, /* xTruncate */ | > | 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 | static int tvfsShmOpen(sqlite3_file*); static int tvfsShmSize(sqlite3_file*, int , int *); static int tvfsShmGet(sqlite3_file*, int , int *, volatile void **); static int tvfsShmRelease(sqlite3_file*); static int tvfsShmLock(sqlite3_file*, int , int, int); static void tvfsShmBarrier(sqlite3_file*); static int tvfsShmClose(sqlite3_file*, int); static int tvfsShmPage(sqlite3_file*,int,int,int, void volatile **); static sqlite3_io_methods tvfs_io_methods = { 2, /* iVersion */ tvfsClose, /* xClose */ tvfsRead, /* xRead */ tvfsWrite, /* xWrite */ tvfsTruncate, /* xTruncate */ |
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156 157 158 159 160 161 162 | tvfsDeviceCharacteristics, /* xDeviceCharacteristics */ tvfsShmOpen, /* xShmOpen */ tvfsShmSize, /* xShmSize */ tvfsShmGet, /* xShmGet */ tvfsShmRelease, /* xShmRelease */ tvfsShmLock, /* xShmLock */ tvfsShmBarrier, /* xShmBarrier */ | | > | 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 | tvfsDeviceCharacteristics, /* xDeviceCharacteristics */ tvfsShmOpen, /* xShmOpen */ tvfsShmSize, /* xShmSize */ tvfsShmGet, /* xShmGet */ tvfsShmRelease, /* xShmRelease */ tvfsShmLock, /* xShmLock */ tvfsShmBarrier, /* xShmBarrier */ tvfsShmClose, /* xShmClose */ tvfsShmPage /* xShmPage */ }; static int tvfsResultCode(Testvfs *p, int *pRc){ struct errcode { int eCode; const char *zCode; } aCode[] = { |
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543 544 545 546 547 548 549 | /* ** Return the current time as a Julian Day number in *pTimeOut. */ static int tvfsCurrentTime(sqlite3_vfs *pVfs, double *pTimeOut){ return PARENTVFS(pVfs)->xCurrentTime(PARENTVFS(pVfs), pTimeOut); } | < < < < < < < < < < | 549 550 551 552 553 554 555 556 557 558 559 560 561 562 | /* ** Return the current time as a Julian Day number in *pTimeOut. */ static int tvfsCurrentTime(sqlite3_vfs *pVfs, double *pTimeOut){ return PARENTVFS(pVfs)->xCurrentTime(PARENTVFS(pVfs), pTimeOut); } static int tvfsInjectIoerr(Testvfs *p){ int ret = 0; if( p->ioerr ){ p->iIoerrCnt--; if( p->iIoerrCnt==0 || (p->iIoerrCnt<0 && p->ioerr==2) ){ ret = 1; p->nIoerrFail++; |
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620 621 622 623 624 625 626 | } static int tvfsShmSize( sqlite3_file *pFile, int reqSize, int *pNewSize ){ | < < < | < < < < < < < < < < < < | < > | < < | < | < < | < > | < < | > > > > > > | < < < | > > > > > > | > > > > | | > > | > > > > > > > | 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 | } static int tvfsShmSize( sqlite3_file *pFile, int reqSize, int *pNewSize ){ assert(0); return SQLITE_OK; } static int tvfsShmGet( sqlite3_file *pFile, int reqMapSize, int *pMapSize, volatile void **pp ){ assert(0); return SQLITE_OK; } static int tvfsShmRelease(sqlite3_file *pFile){ assert(0); return SQLITE_OK; } static void tvfsAllocPage(TestvfsBuffer *p, int iPage, int pgsz){ assert( iPage<TESTVFS_MAX_PAGES ); if( p->aPage[iPage]==0 ){ p->aPage[iPage] = ckalloc(pgsz); memset(p->aPage[iPage], 0, pgsz); p->pgsz = pgsz; } } static int tvfsShmPage( sqlite3_file *pFile, /* Handle open on database file */ int iPage, /* Page to retrieve */ int pgsz, /* Size of pages */ int isWrite, /* True to extend file if necessary */ void volatile **pp /* OUT: Mapped memory */ ){ int rc = SQLITE_OK; TestvfsFile *pFd = (TestvfsFile *)pFile; Testvfs *p = (Testvfs *)(pFd->pVfs->pAppData); if( p->pScript && p->mask&TESTVFS_SHMPAGE_MASK ){ Tcl_Obj *pArg = Tcl_NewObj(); Tcl_ListObjAppendElement(p->interp, pArg, Tcl_NewIntObj(iPage)); Tcl_ListObjAppendElement(p->interp, pArg, Tcl_NewIntObj(pgsz)); Tcl_ListObjAppendElement(p->interp, pArg, Tcl_NewIntObj(isWrite)); tvfsExecTcl(p, "xShmPage", Tcl_NewStringObj(pFd->pShm->zFile, -1), pFd->pShmId, pArg ); tvfsResultCode(p, &rc); } if( rc==SQLITE_OK && p->mask&TESTVFS_SHMPAGE_MASK && tvfsInjectIoerr(p) ){ rc = SQLITE_IOERR; } if( rc==SQLITE_OK && isWrite && !pFd->pShm->aPage[iPage] ){ tvfsAllocPage(pFd->pShm, iPage, pgsz); } *pp = (void volatile *)pFd->pShm->aPage[iPage]; return rc; } static int tvfsShmLock( sqlite3_file *pFile, int ofst, int n, int flags ){ |
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778 779 780 781 782 783 784 785 786 787 | } for(ppFd=&pBuffer->pFile; *ppFd!=pFd; ppFd=&((*ppFd)->pNext)); assert( (*ppFd)==pFd ); *ppFd = pFd->pNext; if( pBuffer->pFile==0 ){ TestvfsBuffer **pp; for(pp=&p->pBuffer; *pp!=pBuffer; pp=&((*pp)->pNext)); *pp = (*pp)->pNext; | > > | > | 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 | } for(ppFd=&pBuffer->pFile; *ppFd!=pFd; ppFd=&((*ppFd)->pNext)); assert( (*ppFd)==pFd ); *ppFd = pFd->pNext; if( pBuffer->pFile==0 ){ int i; TestvfsBuffer **pp; for(pp=&p->pBuffer; *pp!=pBuffer; pp=&((*pp)->pNext)); *pp = (*pp)->pNext; for(i=0; pBuffer->aPage[i]; i++){ ckfree((char *)pBuffer->aPage[i]); } ckfree((char *)pBuffer); } pFd->pShm = 0; return rc; } |
︙ | ︙ | |||
817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 | if( Tcl_GetIndexFromObj(interp, objv[1], CMD_strs, "subcommand", 0, &i) ){ return TCL_ERROR; } Tcl_ResetResult(interp); switch( (enum DB_enum)i ){ case CMD_SHM: { TestvfsBuffer *pBuffer; char *zName; if( objc!=3 && objc!=4 ){ Tcl_WrongNumArgs(interp, 2, objv, "FILE ?VALUE?"); return TCL_ERROR; } zName = Tcl_GetString(objv[2]); for(pBuffer=p->pBuffer; pBuffer; pBuffer=pBuffer->pNext){ if( 0==strcmp(pBuffer->zFile, zName) ) break; } if( !pBuffer ){ Tcl_AppendResult(interp, "no such file: ", zName, 0); return TCL_ERROR; } if( objc==4 ){ int n; u8 *a = Tcl_GetByteArrayFromObj(objv[3], &n); | > > | > > > > | > | | > > > > > > | | 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 | if( Tcl_GetIndexFromObj(interp, objv[1], CMD_strs, "subcommand", 0, &i) ){ return TCL_ERROR; } Tcl_ResetResult(interp); switch( (enum DB_enum)i ){ case CMD_SHM: { Tcl_Obj *pObj; int i; TestvfsBuffer *pBuffer; char *zName; if( objc!=3 && objc!=4 ){ Tcl_WrongNumArgs(interp, 2, objv, "FILE ?VALUE?"); return TCL_ERROR; } zName = Tcl_GetString(objv[2]); for(pBuffer=p->pBuffer; pBuffer; pBuffer=pBuffer->pNext){ if( 0==strcmp(pBuffer->zFile, zName) ) break; } if( !pBuffer ){ Tcl_AppendResult(interp, "no such file: ", zName, 0); return TCL_ERROR; } if( objc==4 ){ int n; u8 *a = Tcl_GetByteArrayFromObj(objv[3], &n); assert( pBuffer->pgsz==0 || pBuffer->pgsz==32768 ); for(i=0; i*32768<n; i++){ int nByte = 32768; tvfsAllocPage(pBuffer, i, 32768); if( n-i*32768<32768 ){ nByte = n; } memcpy(pBuffer->aPage[i], &a[i*32768], nByte); } } pObj = Tcl_NewObj(); for(i=0; pBuffer->aPage[i]; i++){ Tcl_AppendObjToObj(pObj, Tcl_NewByteArrayObj(pBuffer->aPage[i], 32768)); } Tcl_SetObjResult(interp, pObj); break; } case CMD_FILTER: { static struct VfsMethod { char *zName; int mask; |
︙ | ︙ |
Changes to src/wal.c.
︙ | ︙ | |||
366 367 368 369 370 371 372 | ** following object. */ struct Wal { sqlite3_vfs *pVfs; /* The VFS used to create pDbFd */ sqlite3_file *pDbFd; /* File handle for the database file */ sqlite3_file *pWalFd; /* File handle for WAL file */ u32 iCallback; /* Value to pass to log callback (or 0) */ | | | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | | < < | | | > > | | 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 | ** following object. */ struct Wal { sqlite3_vfs *pVfs; /* The VFS used to create pDbFd */ sqlite3_file *pDbFd; /* File handle for the database file */ sqlite3_file *pWalFd; /* File handle for WAL file */ u32 iCallback; /* Value to pass to log callback (or 0) */ int nWiData; /* Size of array apWiData */ volatile u32 **apWiData; /* Pointer to wal-index content in memory */ u16 szPage; /* Database page size */ i16 readLock; /* Which read lock is being held. -1 for none */ u8 exclusiveMode; /* Non-zero if connection is in exclusive mode */ u8 isWIndexOpen; /* True if ShmOpen() called on pDbFd */ u8 writeLock; /* True if in a write transaction */ u8 ckptLock; /* True if holding a checkpoint lock */ WalIndexHdr hdr; /* Wal-index header for current transaction */ char *zWalName; /* Name of WAL file */ u32 nCkpt; /* Checkpoint sequence counter in the wal-header */ #ifdef SQLITE_DEBUG u8 lockError; /* True if a locking error has occurred */ #endif }; /* ** Define the parameters of the hash tables in the wal-index file. There ** is a hash-table following every HASHTABLE_NPAGE page numbers in the ** wal-index. ** ** Changing any of these constants will alter the wal-index format and ** create incompatibilities. */ #define HASHTABLE_NPAGE 4096 /* Must be power of 2 and multiple of 256 */ #define HASHTABLE_DATATYPE u16 #define HASHTABLE_HASH_1 383 /* Should be prime */ #define HASHTABLE_NSLOT (HASHTABLE_NPAGE*2) /* Must be a power of 2 */ #define HASHTABLE_NBYTE (sizeof(HASHTABLE_DATATYPE)*HASHTABLE_NSLOT) /* The block of page numbers associated with the first hash-table in a ** wal-index is smaller than usual. This is so that there is a complete ** hash-table on each aligned 32KB page of the wal-index. */ #define HASHTABLE_NPAGE_ONE (4096 - (WALINDEX_HDR_SIZE/sizeof(u32))) /* The wal-index is divided into pages of HASHTABLE_PAGESIZE bytes each. */ #define HASHTABLE_PAGESIZE (HASHTABLE_NBYTE + HASHTABLE_NPAGE*sizeof(u32)) /* ** Obtain a pointer to the iPage'th page of the wal-index. The wal-index ** is broken into pages of HASHTABLE_PAGESIZE bytes. Wal-index pages are ** numbered from zero. ** ** If this call is successful, *ppPage is set to point to the wal-index ** page and SQLITE_OK is returned. If an error (an OOM or VFS error) occurs, ** then an SQLite error code is returned and *ppPage is set to 0. */ static int walIndexPage(Wal *pWal, int iPage, volatile u32 **ppPage){ int rc = SQLITE_OK; /* Enlarge the pWal->apWiData[] array if required */ if( pWal->nWiData<=iPage ){ int nByte = sizeof(u32 *)*(iPage+1); volatile u32 **apNew; apNew = (volatile u32 **)sqlite3_realloc(pWal->apWiData, nByte); if( !apNew ){ *ppPage = 0; return SQLITE_NOMEM; } memset(&apNew[pWal->nWiData], 0, sizeof(u32 *)*(iPage+1-pWal->nWiData)); pWal->apWiData = apNew; pWal->nWiData = iPage+1; } /* Request a pointer to the required page from the VFS */ if( pWal->apWiData[iPage]==0 ){ rc = sqlite3OsShmPage(pWal->pDbFd, iPage, HASHTABLE_PAGESIZE, pWal->writeLock, (void volatile **)&pWal->apWiData[iPage] ); } *ppPage = pWal->apWiData[iPage]; assert( iPage==0 || *ppPage || rc!=SQLITE_OK ); return rc; } /* ** Return a pointer to the WalCkptInfo structure in the wal-index. */ static volatile WalCkptInfo *walCkptInfo(Wal *pWal){ volatile u32 *page1 = 0; walIndexPage(pWal, 0, &page1); assert( page1 ); return (volatile WalCkptInfo*)&page1[sizeof(WalIndexHdr)/2]; } /* ** This structure is used to implement an iterator that loops through ** all frames in the WAL in database page order. Where two or more frames ** correspond to the same database page, the iterator visits only the ** frame most recently written to the WAL (in other words, the frame with ** the largest index). ** ** The internals of this structure are only accessed by: ** ** walIteratorInit() - Create a new iterator, ** walIteratorNext() - Step an iterator, ** walIteratorFree() - Free an iterator. ** ** This functionality is used by the checkpoint code (see walCheckpoint()). */ struct WalIterator { int iPrior; /* Last result returned from the iterator */ int nSegment; /* Size of the aSegment[] array */ struct WalSegment { int iNext; /* Next slot in aIndex[] not yet returned */ HASHTABLE_DATATYPE *aIndex; /* i0, i1, i2... such that aPgno[iN] ascend */ u32 *aPgno; /* Array of page numbers. */ int nEntry; /* Max size of aPgno[] and aIndex[] arrays */ int iZero; /* Frame number associated with aPgno[0] */ } aSegment[1]; /* One for every 32KB page in the WAL */ }; /* ** The argument to this macro must be of type u32. On a little-endian ** architecture, it returns the u32 value that results from interpreting ** the 4 bytes as a big-endian value. On a big-endian architecture, it ** returns the value that would be produced by intepreting the 4 bytes |
︙ | ︙ | |||
488 489 490 491 492 493 494 | static void walIndexWriteHdr(Wal *pWal){ WalIndexHdr *aHdr; assert( pWal->writeLock ); pWal->hdr.isInit = 1; walChecksumBytes(1, (u8*)&pWal->hdr, offsetof(WalIndexHdr, aCksum), 0, pWal->hdr.aCksum); | | | 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 | static void walIndexWriteHdr(Wal *pWal){ WalIndexHdr *aHdr; assert( pWal->writeLock ); pWal->hdr.isInit = 1; walChecksumBytes(1, (u8*)&pWal->hdr, offsetof(WalIndexHdr, aCksum), 0, pWal->hdr.aCksum); walIndexPage(pWal, 0, (volatile u32 **)&aHdr); memcpy(&aHdr[1], &pWal->hdr, sizeof(WalIndexHdr)); sqlite3OsShmBarrier(pWal->pDbFd); memcpy(&aHdr[0], &pWal->hdr, sizeof(WalIndexHdr)); } /* ** This function encodes a single frame header and writes it to a buffer |
︙ | ︙ | |||
582 583 584 585 586 587 588 | ** and the new database size. */ *piPage = pgno; *pnTruncate = sqlite3Get4byte(&aFrame[4]); return 1; } | < < < < < < < < < < < < < | 645 646 647 648 649 650 651 652 653 654 655 656 657 658 | ** and the new database size. */ *piPage = pgno; *pnTruncate = sqlite3Get4byte(&aFrame[4]); return 1; } #if defined(SQLITE_TEST) && defined(SQLITE_DEBUG) /* ** Names of locks. This routine is used to provide debugging output and is not ** a part of an ordinary build. */ static const char *walLockName(int lockIdx){ |
︙ | ︙ | |||
659 660 661 662 663 664 665 | if( pWal->exclusiveMode ) return; (void)sqlite3OsShmLock(pWal->pDbFd, lockIdx, n, SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE); WALTRACE(("WAL%p: release EXCLUSIVE-%s cnt=%d\n", pWal, walLockName(lockIdx), n)); } | < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 | if( pWal->exclusiveMode ) return; (void)sqlite3OsShmLock(pWal->pDbFd, lockIdx, n, SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE); WALTRACE(("WAL%p: release EXCLUSIVE-%s cnt=%d\n", pWal, walLockName(lockIdx), n)); } /* ** Compute a hash on a page number. The resulting hash value must land ** between 0 and (HASHTABLE_NSLOT-1). The walHashNext() function advances ** the hash to the next value in the event of a collision. */ static int walHash(u32 iPage){ assert( iPage>0 ); assert( (HASHTABLE_NSLOT & (HASHTABLE_NSLOT-1))==0 ); return (iPage*HASHTABLE_HASH_1) & (HASHTABLE_NSLOT-1); } static int walNextHash(int iPriorHash){ return (iPriorHash+1)&(HASHTABLE_NSLOT-1); } static void walHashGet( Wal *pWal, /* WAL handle */ int iHash, /* Find the iHash'th table */ volatile HASHTABLE_DATATYPE **paHash, /* OUT: Pointer to hash index */ volatile u32 **paPgno, /* OUT: Pointer to page number array */ u32 *piZero /* OUT: Frame associated with *paPgno[0] */ ){ u32 iZero; volatile u32 *aPgno; volatile HASHTABLE_DATATYPE *aHash; walIndexPage(pWal, iHash, &aPgno); aHash = (volatile HASHTABLE_DATATYPE *)&aPgno[HASHTABLE_NPAGE]; if( iHash==0 ){ aPgno = &aPgno[WALINDEX_HDR_SIZE/sizeof(u32)-1]; iZero = 0; }else{ iZero = HASHTABLE_NPAGE_ONE + (iHash-1)*HASHTABLE_NPAGE; aPgno = &aPgno[-1*iZero-1]; } *paPgno = aPgno; *paHash = aHash; *piZero = iZero; } static int walFramePage(u32 iFrame){ int iHash = (iFrame+HASHTABLE_NPAGE-HASHTABLE_NPAGE_ONE-1) / HASHTABLE_NPAGE; assert( (iHash==0 || iFrame>HASHTABLE_NPAGE_ONE) && (iHash>=1 || iFrame<=HASHTABLE_NPAGE_ONE) && (iHash<=1 || iFrame>(HASHTABLE_NPAGE_ONE+HASHTABLE_NPAGE)) && (iHash>=2 || iFrame<=HASHTABLE_NPAGE_ONE+HASHTABLE_NPAGE) && (iHash<=2 || iFrame>(HASHTABLE_NPAGE_ONE+2*HASHTABLE_NPAGE)) ); return iHash; } /* ** Return the page number associated with frame iFrame in this WAL. */ static u32 walFramePgno(Wal *pWal, u32 iFrame){ int iHash = walFramePage(iFrame); if( iHash==0 ){ return pWal->apWiData[0][WALINDEX_HDR_SIZE/sizeof(u32) + iFrame - 1]; } return pWal->apWiData[iHash][(iFrame-1-HASHTABLE_NPAGE_ONE)%HASHTABLE_NPAGE]; } /* ** Find the hash table and (section of the) page number array used to ** store data for WAL frame iFrame. ** ** Set output variable *paHash to point to the start of the hash table ** in the wal-index file. Set *piZero to one less than the frame |
︙ | ︙ | |||
785 786 787 788 789 790 791 | static void walHashFind( Wal *pWal, /* WAL handle */ u32 iFrame, /* Find the hash table indexing this frame */ volatile HASHTABLE_DATATYPE **paHash, /* OUT: Pointer to hash index */ volatile u32 **paPgno, /* OUT: Pointer to page number array */ u32 *piZero /* OUT: Frame associated with *paPgno[0] */ ){ | < < < | < < < | < < < < < < < < < < < < < > > < < < | > | | | < | 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 | static void walHashFind( Wal *pWal, /* WAL handle */ u32 iFrame, /* Find the hash table indexing this frame */ volatile HASHTABLE_DATATYPE **paHash, /* OUT: Pointer to hash index */ volatile u32 **paPgno, /* OUT: Pointer to page number array */ u32 *piZero /* OUT: Frame associated with *paPgno[0] */ ){ int iHash = walFramePage(iFrame); walHashGet(pWal, iHash, paHash, paPgno, piZero); } /* ** Remove entries from the hash table that point to WAL slots greater ** than pWal->hdr.mxFrame. ** ** This function is called whenever pWal->hdr.mxFrame is decreased due ** to a rollback or savepoint. ** ** At most only the hash table containing pWal->hdr.mxFrame needs to be ** updated. Any later hash tables will be automatically cleared when ** pWal->hdr.mxFrame advances to the point where those hash tables are ** actually needed. */ static void walCleanupHash(Wal *pWal){ volatile HASHTABLE_DATATYPE *aHash; /* Pointer to hash table to clear */ volatile u32 *aPgno; /* Unused return from walHashFind() */ u32 iZero; /* frame == (aHash[x]+iZero) */ int iLimit = 0; /* Zero values greater than this */ int nByte; /* Number of bytes to zero in aPgno[] */ int i; /* Used to iterate through aHash[] */ assert( pWal->writeLock ); testcase( pWal->hdr.mxFrame==HASHTABLE_NPAGE-1 ); testcase( pWal->hdr.mxFrame==HASHTABLE_NPAGE ); testcase( pWal->hdr.mxFrame==HASHTABLE_NPAGE+1 ); walHashFind(pWal, pWal->hdr.mxFrame+1, &aHash, &aPgno, &iZero); if( iZero!=pWal->hdr.mxFrame ){ iLimit = pWal->hdr.mxFrame - iZero; assert( iLimit>0 ); for(i=0; i<HASHTABLE_NSLOT; i++){ if( aHash[i]>iLimit ){ aHash[i] = 0; } } /* Zero the entries in the aPgno array that correspond to frames with ** frame numbers greater than pWal->hdr.mxFrame. */ nByte = ((char *)aHash - (char *)&aPgno[pWal->hdr.mxFrame+1]); memset((void *)&aPgno[pWal->hdr.mxFrame+1], 0, nByte); } #ifdef SQLITE_ENABLE_EXPENSIVE_ASSERT /* Verify that the every entry in the mapping region is still reachable ** via the hash table even after the cleanup. */ if( iLimit ){ |
︙ | ︙ | |||
874 875 876 877 878 879 880 | /* ** Set an entry in the wal-index that will map database page number ** pPage into WAL frame iFrame. */ static int walIndexAppend(Wal *pWal, u32 iFrame, u32 iPage){ | | < < < < < < < < > | < | 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 | /* ** Set an entry in the wal-index that will map database page number ** pPage into WAL frame iFrame. */ static int walIndexAppend(Wal *pWal, u32 iFrame, u32 iPage){ int rc = SQLITE_OK; /* Return code */ /* Assuming the wal-index file was successfully mapped, find the hash ** table and section of of the page number array that pertain to frame ** iFrame of the WAL. Then populate the page number array and the hash ** table entry. */ if( rc==SQLITE_OK ){ int iKey; /* Hash table key */ u32 iZero; /* One less than frame number of aPgno[1] */ volatile u32 *aPgno; /* Page number array */ volatile HASHTABLE_DATATYPE *aHash; /* Hash table */ int idx; /* Value to write to hash-table slot */ TESTONLY( int nCollide = 0; /* Number of hash collisions */ ) walHashFind(pWal, iFrame, &aHash, &aPgno, &iZero); idx = iFrame - iZero; if( idx==1 ){ int nByte = (u8 *)&aHash[HASHTABLE_NSLOT] - (u8 *)&aPgno[1+iZero]; memset((void*)&aPgno[1+iZero], 0, nByte); } assert( idx <= HASHTABLE_NSLOT/2 + 1 ); if( aPgno[iFrame] ){ /* If the entry in aPgno[] is already set, then the previous writer ** must have exited unexpectedly in the middle of a transaction (after ** writing one or more dirty pages to the WAL to free up memory). |
︙ | ︙ | |||
1072 1073 1074 1075 1076 1077 1078 | } } sqlite3_free(aFrame); } finished: | < < < | 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 | } } sqlite3_free(aFrame); } finished: if( rc==SQLITE_OK ){ volatile WalCkptInfo *pInfo; int i; pWal->hdr.aFrameCksum[0] = aFrameCksum[0]; pWal->hdr.aFrameCksum[1] = aFrameCksum[1]; walIndexWriteHdr(pWal); |
︙ | ︙ | |||
1160 1161 1162 1163 1164 1165 1166 | if( !pRet ){ return SQLITE_NOMEM; } pRet->pVfs = pVfs; pRet->pWalFd = (sqlite3_file *)&pRet[1]; pRet->pDbFd = pDbFd; | < | 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 | if( !pRet ){ return SQLITE_NOMEM; } pRet->pVfs = pVfs; pRet->pWalFd = (sqlite3_file *)&pRet[1]; pRet->pDbFd = pDbFd; pRet->readLock = -1; sqlite3_randomness(8, &pRet->hdr.aSalt); pRet->zWalName = zWal = pVfs->szOsFile + (char*)pRet->pWalFd; sqlite3_snprintf(nWal, zWal, "%s-wal", zDbName); rc = sqlite3OsShmOpen(pDbFd); /* Open file handle on the write-ahead log file. */ |
︙ | ︙ | |||
1203 1204 1205 1206 1207 1208 1209 | WalIterator *p, /* Iterator */ u32 *piPage, /* OUT: The page number of the next page */ u32 *piFrame /* OUT: Wal frame index of next page */ ){ u32 iMin; /* Result pgno must be greater than iMin */ u32 iRet = 0xFFFFFFFF; /* 0xffffffff is never a valid page number */ int i; /* For looping through segments */ | < | | < | | | | < < > > | | | | 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 | WalIterator *p, /* Iterator */ u32 *piPage, /* OUT: The page number of the next page */ u32 *piFrame /* OUT: Wal frame index of next page */ ){ u32 iMin; /* Result pgno must be greater than iMin */ u32 iRet = 0xFFFFFFFF; /* 0xffffffff is never a valid page number */ int i; /* For looping through segments */ iMin = p->iPrior; assert( iMin<0xffffffff ); for(i=p->nSegment-1; i>=0; i--){ struct WalSegment *pSegment = &p->aSegment[i]; while( pSegment->iNext<pSegment->nEntry ){ u32 iPg = pSegment->aPgno[pSegment->aIndex[pSegment->iNext]]; if( iPg>iMin ){ if( iPg<iRet ){ iRet = iPg; *piFrame = pSegment->iZero + pSegment->aIndex[pSegment->iNext]; } break; } pSegment->iNext++; } } *piPage = p->iPrior = iRet; return (iRet==0xFFFFFFFF); } static void walMergesort( u32 *aContent, /* Pages in wal */ HASHTABLE_DATATYPE *aBuffer, /* Buffer of at least *pnList items to use */ HASHTABLE_DATATYPE *aList, /* IN/OUT: List to sort */ int *pnList /* IN/OUT: Number of elements in aList[] */ ){ int nList = *pnList; if( nList>1 ){ int nLeft = nList / 2; /* Elements in left list */ int nRight = nList - nLeft; /* Elements in right list */ int iLeft = 0; /* Current index in aLeft */ int iRight = 0; /* Current index in aright */ int iOut = 0; /* Current index in output buffer */ HASHTABLE_DATATYPE *aLeft = aList; /* Left list */ HASHTABLE_DATATYPE *aRight = &aList[nLeft]; /* Right list */ /* TODO: Change to non-recursive version. */ walMergesort(aContent, aBuffer, aLeft, &nLeft); walMergesort(aContent, aBuffer, aRight, &nRight); while( iRight<nRight || iLeft<nLeft ){ HASHTABLE_DATATYPE logpage; Pgno dbpage; if( (iLeft<nLeft) && (iRight>=nRight || aContent[aLeft[iLeft]]<aContent[aRight[iRight]]) ){ logpage = aLeft[iLeft++]; }else{ |
︙ | ︙ | |||
1296 1297 1298 1299 1300 1301 1302 | ** ** The calling routine should invoke walIteratorFree() to destroy the ** WalIterator object when it has finished with it. The caller must ** also unmap the wal-index. But the wal-index must not be unmapped ** prior to the WalIterator object being destroyed. */ static int walIteratorInit(Wal *pWal, WalIterator **pp){ | < < | | < < < | | < | < | > > | < < < | | > > > > > > | > > > > > > > | | | | > > | > | < > | | 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 | ** ** The calling routine should invoke walIteratorFree() to destroy the ** WalIterator object when it has finished with it. The caller must ** also unmap the wal-index. But the wal-index must not be unmapped ** prior to the WalIterator object being destroyed. */ static int walIteratorInit(Wal *pWal, WalIterator **pp){ WalIterator *p; /* Return value */ int nSegment; /* Number of segments to merge */ u32 iLast; /* Last frame in log */ int nByte; /* Number of bytes to allocate */ int i; /* Iterator variable */ HASHTABLE_DATATYPE *aTmp; /* Temp space used by merge-sort */ HASHTABLE_DATATYPE *aSpace; /* Space at the end of the allocation */ /* This routine only runs while holding SQLITE_SHM_CHECKPOINT. No other ** thread is able to write to shared memory while this routine is ** running (or, indeed, while the WalIterator object exists). Hence, ** we can cast off the volatile qualification from shared memory */ assert( pWal->ckptLock ); iLast = pWal->hdr.mxFrame; /* Allocate space for the WalIterator object */ nSegment = walFramePage(iLast) + 1; nByte = sizeof(WalIterator) + nSegment*(sizeof(struct WalSegment)) + (nSegment+1)*(HASHTABLE_NPAGE * sizeof(HASHTABLE_DATATYPE)); p = (WalIterator *)sqlite3_malloc(nByte); if( !p ){ return SQLITE_NOMEM; } memset(p, 0, nByte); /* Allocate space for the WalIterator object */ p->nSegment = nSegment; aSpace = (HASHTABLE_DATATYPE *)&p->aSegment[nSegment]; aTmp = &aSpace[HASHTABLE_NPAGE*nSegment]; for(i=0; i<nSegment; i++){ volatile HASHTABLE_DATATYPE *pDummy; int j; u32 iZero; int nEntry; volatile u32 *aPgno; walHashGet(pWal, i, &pDummy, &aPgno, &iZero); if( i==(nSegment-1) ){ nEntry = iLast - iZero; }else if( i==0 ){ nEntry = HASHTABLE_NPAGE_ONE; }else{ nEntry = HASHTABLE_NPAGE; } iZero++; aPgno += iZero; for(j=0; j<nEntry; j++){ aSpace[j] = j; } walMergesort((u32 *)aPgno, aTmp, aSpace, &nEntry); p->aSegment[i].iZero = iZero; p->aSegment[i].nEntry = nEntry; p->aSegment[i].aIndex = aSpace; p->aSegment[i].aPgno = (u32 *)aPgno; aSpace += HASHTABLE_NPAGE; } assert( aSpace==aTmp ); /* Return the fully initialized WalIterator object */ *pp = p; return SQLITE_OK ; } /* ** Free an iterator allocated by walIteratorInit(). */ |
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1426 1427 1428 1429 1430 1431 1432 | /* Compute in mxSafeFrame the index of the last frame of the WAL that is ** safe to write into the database. Frames beyond mxSafeFrame might ** overwrite database pages that are in use by active readers and thus ** cannot be backfilled from the WAL. */ mxSafeFrame = pWal->hdr.mxFrame; | | | | 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 | /* Compute in mxSafeFrame the index of the last frame of the WAL that is ** safe to write into the database. Frames beyond mxSafeFrame might ** overwrite database pages that are in use by active readers and thus ** cannot be backfilled from the WAL. */ mxSafeFrame = pWal->hdr.mxFrame; walIndexPage(pWal, 0, (volatile u32 **)&pHdr); pInfo = walCkptInfo(pWal); assert( pInfo==walCkptInfo(pWal) ); for(i=1; i<WAL_NREADER; i++){ u32 y = pInfo->aReadMark[i]; if( mxSafeFrame>=y ){ assert( y<=pWal->hdr.mxFrame ); rc = walLockExclusive(pWal, WAL_READ_LOCK(i), 1); if( rc==SQLITE_OK ){ |
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1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 | /* Sync the WAL to disk */ if( sync_flags ){ rc = sqlite3OsSync(pWal->pWalFd, sync_flags); } /* Iterate through the contents of the WAL, copying data to the db file. */ while( rc==SQLITE_OK && 0==walIteratorNext(pIter, &iDbpage, &iFrame) ){ if( iFrame<=nBackfill || iFrame>mxSafeFrame ) continue; rc = sqlite3OsRead(pWal->pWalFd, zBuf, szPage, walFrameOffset(iFrame, szPage) + WAL_FRAME_HDRSIZE ); if( rc!=SQLITE_OK ) break; rc = sqlite3OsWrite(pWal->pDbFd, zBuf, szPage, (iDbpage-1)*szPage); if( rc!=SQLITE_OK ) break; | > | 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 | /* Sync the WAL to disk */ if( sync_flags ){ rc = sqlite3OsSync(pWal->pWalFd, sync_flags); } /* Iterate through the contents of the WAL, copying data to the db file. */ while( rc==SQLITE_OK && 0==walIteratorNext(pIter, &iDbpage, &iFrame) ){ assert( walFramePgno(pWal, iFrame)==iDbpage ); if( iFrame<=nBackfill || iFrame>mxSafeFrame ) continue; rc = sqlite3OsRead(pWal->pWalFd, zBuf, szPage, walFrameOffset(iFrame, szPage) + WAL_FRAME_HDRSIZE ); if( rc!=SQLITE_OK ) break; rc = sqlite3OsWrite(pWal->pDbFd, zBuf, szPage, (iDbpage-1)*szPage); if( rc!=SQLITE_OK ) break; |
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1521 1522 1523 1524 1525 1526 1527 | rc = sqlite3OsLock(pWal->pDbFd, SQLITE_LOCK_EXCLUSIVE); if( rc==SQLITE_OK ){ pWal->exclusiveMode = 1; rc = sqlite3WalCheckpoint(pWal, sync_flags, nBuf, zBuf); if( rc==SQLITE_OK ){ isDelete = 1; } | < > | 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 | rc = sqlite3OsLock(pWal->pDbFd, SQLITE_LOCK_EXCLUSIVE); if( rc==SQLITE_OK ){ pWal->exclusiveMode = 1; rc = sqlite3WalCheckpoint(pWal, sync_flags, nBuf, zBuf); if( rc==SQLITE_OK ){ isDelete = 1; } } walIndexClose(pWal, isDelete); sqlite3OsClose(pWal->pWalFd); if( isDelete ){ sqlite3OsDelete(pWal->pVfs, pWal->zWalName, 0); } WALTRACE(("WAL%p: closed\n", pWal)); sqlite3_free(pWal->apWiData); sqlite3_free(pWal); } return rc; } /* ** Try to read the wal-index header. Return 0 on success and 1 if |
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1556 1557 1558 1559 1560 1561 1562 1563 | ** If the checksum cannot be verified return non-zero. If the header ** is read successfully and the checksum verified, return zero. */ int walIndexTryHdr(Wal *pWal, int *pChanged){ u32 aCksum[2]; /* Checksum on the header content */ WalIndexHdr h1, h2; /* Two copies of the header content */ WalIndexHdr *aHdr; /* Header in shared memory */ | > > | < | | 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 | ** If the checksum cannot be verified return non-zero. If the header ** is read successfully and the checksum verified, return zero. */ int walIndexTryHdr(Wal *pWal, int *pChanged){ u32 aCksum[2]; /* Checksum on the header content */ WalIndexHdr h1, h2; /* Two copies of the header content */ WalIndexHdr *aHdr; /* Header in shared memory */ volatile u32 *page1 = 0; walIndexPage(pWal, 0, &page1); if( !page1 ){ /* The wal-index is not large enough to hold the header, then assume ** header is invalid. */ return 1; } /* Read the header. This might happen currently with a write to the ** same area of shared memory on a different CPU in a SMP, ** meaning it is possible that an inconsistent snapshot is read ** from the file. If this happens, return non-zero. ** ** There are two copies of the header at the beginning of the wal-index. ** When reading, read [0] first then [1]. Writes are in the reverse order. ** Memory barriers are used to prevent the compiler or the hardware from ** reordering the reads and writes. */ aHdr = (WalIndexHdr*)page1; memcpy(&h1, &aHdr[0], sizeof(h1)); sqlite3OsShmBarrier(pWal->pDbFd); memcpy(&h2, &aHdr[1], sizeof(h2)); if( memcmp(&h1, &h2, sizeof(h1))!=0 ){ return 1; /* Dirty read */ } |
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1621 1622 1623 1624 1625 1626 1627 1628 1629 | ** ** If the wal-index header is successfully read, return SQLITE_OK. ** Otherwise an SQLite error code. */ static int walIndexReadHdr(Wal *pWal, int *pChanged){ int rc; /* Return code */ int badHdr; /* True if a header read failed */ assert( pChanged ); | > | | 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 | ** ** If the wal-index header is successfully read, return SQLITE_OK. ** Otherwise an SQLite error code. */ static int walIndexReadHdr(Wal *pWal, int *pChanged){ int rc; /* Return code */ int badHdr; /* True if a header read failed */ volatile u32 *dummy; assert( pChanged ); rc = walIndexPage(pWal, 0, &dummy); if( rc!=SQLITE_OK ){ return rc; } /* Try once to read the header straight out. This works most of the ** time. */ |
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1655 1656 1657 1658 1659 1660 1661 | *pChanged = 1; } walUnlockExclusive(pWal, WAL_WRITE_LOCK, 1); pWal->writeLock = 0; } } | < < < < < < < < | 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 | *pChanged = 1; } walUnlockExclusive(pWal, WAL_WRITE_LOCK, 1); pWal->writeLock = 0; } } return rc; } /* ** This is the value that walTryBeginRead returns when it needs to ** be retried. */ |
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1706 1707 1708 1709 1710 1711 1712 | */ static int walTryBeginRead(Wal *pWal, int *pChanged, int useWal, int cnt){ volatile WalIndexHdr *pHdr; /* Header of the wal-index */ volatile WalCkptInfo *pInfo; /* Checkpoint information in wal-index */ u32 mxReadMark; /* Largest aReadMark[] value */ int mxI; /* Index of largest aReadMark[] value */ int i; /* Loop counter */ | | | 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 | */ static int walTryBeginRead(Wal *pWal, int *pChanged, int useWal, int cnt){ volatile WalIndexHdr *pHdr; /* Header of the wal-index */ volatile WalCkptInfo *pInfo; /* Checkpoint information in wal-index */ u32 mxReadMark; /* Largest aReadMark[] value */ int mxI; /* Index of largest aReadMark[] value */ int i; /* Loop counter */ int rc = SQLITE_OK; /* Return code */ assert( pWal->readLock<0 ); /* Not currently locked */ /* Take steps to avoid spinning forever if there is a protocol error. */ if( cnt>5 ){ if( cnt>100 ) return SQLITE_PROTOCOL; sqlite3OsSleep(pWal->pVfs, 1); |
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1735 1736 1737 1738 1739 1740 1741 | if( rc==SQLITE_OK ){ walUnlockShared(pWal, WAL_RECOVER_LOCK); rc = WAL_RETRY; }else if( rc==SQLITE_BUSY ){ rc = SQLITE_BUSY_RECOVERY; } } | < < | | | | 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 | if( rc==SQLITE_OK ){ walUnlockShared(pWal, WAL_RECOVER_LOCK); rc = WAL_RETRY; }else if( rc==SQLITE_BUSY ){ rc = SQLITE_BUSY_RECOVERY; } } } if( rc!=SQLITE_OK ){ return rc; } walIndexPage(pWal, 0, (volatile u32 **)&pHdr); pInfo = walCkptInfo(pWal); assert( pInfo==(volatile WalCkptInfo *)&pHdr[2] ); if( !useWal && pInfo->nBackfill==pWal->hdr.mxFrame ){ /* The WAL has been completely backfilled (or it is empty). ** and can be safely ignored. */ rc = walLockShared(pWal, WAL_READ_LOCK(0)); sqlite3OsShmBarrier(pWal->pDbFd); if( rc==SQLITE_OK ){ |
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1879 1880 1881 1882 1883 1884 1885 | int sqlite3WalBeginReadTransaction(Wal *pWal, int *pChanged){ int rc; /* Return code */ int cnt = 0; /* Number of TryBeginRead attempts */ do{ rc = walTryBeginRead(pWal, pChanged, 0, ++cnt); }while( rc==WAL_RETRY ); | < | 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 | int sqlite3WalBeginReadTransaction(Wal *pWal, int *pChanged){ int rc; /* Return code */ int cnt = 0; /* Number of TryBeginRead attempts */ do{ rc = walTryBeginRead(pWal, pChanged, 0, ++cnt); }while( rc==WAL_RETRY ); return rc; } /* ** Finish with a read transaction. All this does is release the ** read-lock. */ |
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1909 1910 1911 1912 1913 1914 1915 | int sqlite3WalRead( Wal *pWal, /* WAL handle */ Pgno pgno, /* Database page number to read data for */ int *pInWal, /* OUT: True if data is read from WAL */ int nOut, /* Size of buffer pOut in bytes */ u8 *pOut /* Buffer to write page data to */ ){ | < < < < < < < | 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 | int sqlite3WalRead( Wal *pWal, /* WAL handle */ Pgno pgno, /* Database page number to read data for */ int *pInWal, /* OUT: True if data is read from WAL */ int nOut, /* Size of buffer pOut in bytes */ u8 *pOut /* Buffer to write page data to */ ){ u32 iRead = 0; /* If !=0, WAL frame to return data from */ u32 iLast = pWal->hdr.mxFrame; /* Last page in WAL for this reader */ int iHash; /* Used to loop through N hash tables */ /* This routine is only be called from within a read transaction. */ assert( pWal->readLock>=0 || pWal->lockError ); /* If the "last page" field of the wal-index header snapshot is 0, then ** no data will be read from the wal under any circumstances. Return early ** in this case to avoid the walIndexMap/Unmap overhead. Likewise, if ** pWal->readLock==0, then the WAL is ignored by the reader so ** return early, as if the WAL were empty. */ if( iLast==0 || pWal->readLock==0 ){ *pInWal = 0; return SQLITE_OK; } /* Search the hash table or tables for an entry matching page number ** pgno. Each iteration of the following for() loop searches one ** hash table (each hash table indexes up to HASHTABLE_NPAGE frames). ** ** This code may run concurrently to the code in walIndexAppend() ** that adds entries to the wal-index (and possibly to this hash ** table). This means the value just read from the hash |
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1959 1960 1961 1962 1963 1964 1965 | ** (aPgno[iFrame]==pgno): ** This condition filters out normal hash-table collisions. ** ** (iFrame<=iLast): ** This condition filters out entries that were added to the hash ** table after the current read-transaction had started. */ | | < | < < < | < | 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 | ** (aPgno[iFrame]==pgno): ** This condition filters out normal hash-table collisions. ** ** (iFrame<=iLast): ** This condition filters out entries that were added to the hash ** table after the current read-transaction had started. */ for(iHash=walFramePage(iLast); iHash>=0 && iRead==0; iHash--){ volatile HASHTABLE_DATATYPE *aHash; /* Pointer to hash table */ volatile u32 *aPgno; /* Pointer to array of page numbers */ u32 iZero; /* Frame number corresponding to aPgno[0] */ int iKey; /* Hash slot index */ walHashGet(pWal, iHash, &aHash, &aPgno, &iZero); for(iKey=walHash(pgno); aHash[iKey]; iKey=walNextHash(iKey)){ u32 iFrame = aHash[iKey] + iZero; if( iFrame<=iLast && aPgno[iFrame]==pgno ){ assert( iFrame>iRead ); iRead = iFrame; } } } #ifdef SQLITE_ENABLE_EXPENSIVE_ASSERT /* If expensive assert() statements are available, do a linear search ** of the wal-index file content. Make sure the results agree with the ** result obtained using the hash indexes above. */ { u32 iRead2 = 0; u32 iTest; for(iTest=iLast; iTest>0; iTest--){ if( walFramePgno(pWal, iTest)==pgno ){ iRead2 = iTest; break; } } assert( iRead==iRead2 ); } #endif /* If iRead is non-zero, then it is the log frame number that contains the ** required page. Read and return data from the log file. */ if( iRead ){ i64 iOffset = walFrameOffset(iRead, pWal->hdr.szPage) + WAL_FRAME_HDRSIZE; *pInWal = 1; return sqlite3OsRead(pWal->pWalFd, pOut, nOut, iOffset); } *pInWal = 0; |
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2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 | ** thread to write as doing so would cause a fork. So this routine ** returns SQLITE_BUSY in that case and no write transaction is started. ** ** There can only be a single writer active at a time. */ int sqlite3WalBeginWriteTransaction(Wal *pWal){ int rc; /* Cannot start a write transaction without first holding a read ** transaction. */ assert( pWal->readLock>=0 ); /* Only one writer allowed at a time. Get the write lock. Return ** SQLITE_BUSY if unable. */ rc = walLockExclusive(pWal, WAL_WRITE_LOCK, 1); if( rc ){ return rc; } pWal->writeLock = 1; /* If another connection has written to the database file since the ** time the read transaction on this connection was started, then ** the write is disallowed. */ | > | < < < < < | < | 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 | ** thread to write as doing so would cause a fork. So this routine ** returns SQLITE_BUSY in that case and no write transaction is started. ** ** There can only be a single writer active at a time. */ int sqlite3WalBeginWriteTransaction(Wal *pWal){ int rc; volatile u32 *page1; /* Cannot start a write transaction without first holding a read ** transaction. */ assert( pWal->readLock>=0 ); /* Only one writer allowed at a time. Get the write lock. Return ** SQLITE_BUSY if unable. */ rc = walLockExclusive(pWal, WAL_WRITE_LOCK, 1); if( rc ){ return rc; } pWal->writeLock = 1; /* If another connection has written to the database file since the ** time the read transaction on this connection was started, then ** the write is disallowed. */ walIndexPage(pWal, 0, &page1); if( memcmp(&pWal->hdr, (void*)page1, sizeof(WalIndexHdr))!=0 ){ walUnlockExclusive(pWal, WAL_WRITE_LOCK, 1); pWal->writeLock = 0; rc = SQLITE_BUSY; } return rc; } /* ** End a write transaction. The commit has already been done. This ** routine merely releases the lock. */ |
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2098 2099 2100 2101 2102 2103 2104 | int sqlite3WalUndo(Wal *pWal, int (*xUndo)(void *, Pgno), void *pUndoCtx){ int rc = SQLITE_OK; if( pWal->writeLock ){ int unused; Pgno iMax = pWal->hdr.mxFrame; Pgno iFrame; | < < < < | | < | 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 | int sqlite3WalUndo(Wal *pWal, int (*xUndo)(void *, Pgno), void *pUndoCtx){ int rc = SQLITE_OK; if( pWal->writeLock ){ int unused; Pgno iMax = pWal->hdr.mxFrame; Pgno iFrame; rc = walIndexReadHdr(pWal, &unused); if( rc==SQLITE_OK ){ for(iFrame=pWal->hdr.mxFrame+1; ALWAYS(rc==SQLITE_OK) && iFrame<=iMax; iFrame++ ){ /* This call cannot fail. Unless the page for which the page number ** is passed as the second argument is (a) in the cache and ** (b) has an outstanding reference, then xUndo is either a no-op ** (if (a) is false) or simply expels the page from the cache (if (b) ** is false). ** ** If the upper layer is doing a rollback, it is guaranteed that there ** are no outstanding references to any page other than page 1. And ** page 1 is never written to the log until the transaction is ** committed. As a result, the call to xUndo may not fail. */ assert( pWal->writeLock ); assert( walFramePgno(pWal, iFrame)!=1 ); rc = xUndo(pUndoCtx, walFramePgno(pWal, iFrame)); } walCleanupHash(pWal); } } return rc; } /* ** Argument aWalData must point to an array of WAL_SAVEPOINT_NDATA u32 ** values. This function populates the array with values required to |
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2166 2167 2168 2169 2170 2171 2172 | ** to the start of the log. Update the savepoint values to match. */ aWalData[0] = 0; aWalData[3] = pWal->nCkpt; } if( aWalData[0]<pWal->hdr.mxFrame ){ | < < | < < | 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 | ** to the start of the log. Update the savepoint values to match. */ aWalData[0] = 0; aWalData[3] = pWal->nCkpt; } if( aWalData[0]<pWal->hdr.mxFrame ){ pWal->hdr.mxFrame = aWalData[0]; pWal->hdr.aFrameCksum[0] = aWalData[1]; pWal->hdr.aFrameCksum[1] = aWalData[2]; if( rc==SQLITE_OK ){ walCleanupHash(pWal); } } return rc; } /* ** This function is called just before writing a set of frames to the log ** file (see sqlite3WalFrames()). It checks to see if, instead of appending ** to the current log file, it is possible to overwrite the start of the ** existing log file with the new frames (i.e. "reset" the log). If so, ** it sets pWal->hdr.mxFrame to 0. Otherwise, pWal->hdr.mxFrame is left ** unchanged. ** ** SQLITE_OK is returned if no error is encountered (regardless of whether ** or not pWal->hdr.mxFrame is modified). An SQLite error code is returned ** if some error */ static int walRestartLog(Wal *pWal){ int rc = SQLITE_OK; int cnt; if( pWal->readLock==0 ){ volatile WalCkptInfo *pInfo = walCkptInfo(pWal); assert( pInfo->nBackfill==pWal->hdr.mxFrame ); if( pInfo->nBackfill>0 ){ rc = walLockExclusive(pWal, WAL_READ_LOCK(1), WAL_NREADER-1); if( rc==SQLITE_OK ){ /* If all readers are using WAL_READ_LOCK(0) (in other words if no ** readers are currently using the WAL), then the transactions |
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2233 2234 2235 2236 2237 2238 2239 | walUnlockShared(pWal, WAL_READ_LOCK(0)); pWal->readLock = -1; cnt = 0; do{ int notUsed; rc = walTryBeginRead(pWal, ¬Used, 1, ++cnt); }while( rc==WAL_RETRY ); | < < < < < | 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 | walUnlockShared(pWal, WAL_READ_LOCK(0)); pWal->readLock = -1; cnt = 0; do{ int notUsed; rc = walTryBeginRead(pWal, ¬Used, 1, ++cnt); }while( rc==WAL_RETRY ); } return rc; } /* ** Write a set of frames to the log. The caller must hold the write-lock ** on the log file (obtained using sqlite3WalBeginWriteTransaction()). |
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2263 2264 2265 2266 2267 2268 2269 | u8 aFrame[WAL_FRAME_HDRSIZE]; /* Buffer to assemble frame-header in */ PgHdr *p; /* Iterator to run through pList with. */ PgHdr *pLast = 0; /* Last frame in list */ int nLast = 0; /* Number of extra copies of last page */ assert( pList ); assert( pWal->writeLock ); | < < < | 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 | u8 aFrame[WAL_FRAME_HDRSIZE]; /* Buffer to assemble frame-header in */ PgHdr *p; /* Iterator to run through pList with. */ PgHdr *pLast = 0; /* Last frame in list */ int nLast = 0; /* Number of extra copies of last page */ assert( pList ); assert( pWal->writeLock ); #if defined(SQLITE_TEST) && defined(SQLITE_DEBUG) { int cnt; for(cnt=0, p=pList; p; p=p->pDirty, cnt++){} WALTRACE(("WAL%p: frame write begin. %d frames. mxFrame=%d. %s\n", pWal, cnt, pWal->hdr.mxFrame, isCommit ? "Commit" : "Spill")); } #endif /* See if it is possible to write these frames into the start of the ** log file, instead of appending to it at pWal->hdr.mxFrame. */ if( SQLITE_OK!=(rc = walRestartLog(pWal)) ){ return rc; } /* If this is the first frame written into the log, write the WAL ** header to the start of the WAL file. See comments at the top of ** this source file for a description of the WAL header format. */ iFrame = pWal->hdr.mxFrame; if( iFrame==0 ){ |
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2354 2355 2356 2357 2358 2359 2360 | } nLast++; iOffset += szPage; } rc = sqlite3OsSync(pWal->pWalFd, sync_flags); } | < | 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 | } nLast++; iOffset += szPage; } rc = sqlite3OsSync(pWal->pWalFd, sync_flags); } /* Append data to the wal-index. It is not necessary to lock the ** wal-index to do this as the SQLITE_SHM_WRITE lock held on the wal-index ** guarantees that there are no other writers, and no data that may ** be in use by existing readers is being overwritten. */ iFrame = pWal->hdr.mxFrame; |
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2387 2388 2389 2390 2391 2392 2393 | /* If this is a commit, update the wal-index header too. */ if( isCommit ){ walIndexWriteHdr(pWal); pWal->iCallback = iFrame; } } | < < | 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 | /* If this is a commit, update the wal-index header too. */ if( isCommit ){ walIndexWriteHdr(pWal); pWal->iCallback = iFrame; } } WALTRACE(("WAL%p: frame write %s\n", pWal, rc ? "failed" : "ok")); return rc; } /* ** This routine is called to implement sqlite3_wal_checkpoint() and ** related interfaces. ** ** Obtain a CHECKPOINT lock and then backfill as much information as ** we can from WAL into the database. */ int sqlite3WalCheckpoint( Wal *pWal, /* Wal connection */ int sync_flags, /* Flags to sync db file with (or 0) */ int nBuf, /* Size of temporary buffer */ u8 *zBuf /* Temporary buffer to use */ ){ int rc; /* Return code */ int isChanged = 0; /* True if a new wal-index header is loaded */ assert( pWal->ckptLock==0 ); WALTRACE(("WAL%p: checkpoint begins\n", pWal)); rc = walLockExclusive(pWal, WAL_CKPT_LOCK, 1); if( rc ){ /* Usually this is SQLITE_BUSY meaning that another thread or process ** is already running a checkpoint, or maybe a recovery. But it might |
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2437 2438 2439 2440 2441 2442 2443 | ** next time the pager opens a snapshot on this database it knows that ** the cache needs to be reset. */ memset(&pWal->hdr, 0, sizeof(WalIndexHdr)); } /* Release the locks. */ | < | 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 | ** next time the pager opens a snapshot on this database it knows that ** the cache needs to be reset. */ memset(&pWal->hdr, 0, sizeof(WalIndexHdr)); } /* Release the locks. */ walUnlockExclusive(pWal, WAL_CKPT_LOCK, 1); pWal->ckptLock = 0; WALTRACE(("WAL%p: checkpoint %s\n", pWal, rc ? "failed" : "ok")); return rc; } /* Return the value to pass to a sqlite3_wal_hook callback, the |
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Changes to test/permutations.test.
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9 10 11 12 13 14 15 16 17 18 19 20 21 22 | # #*********************************************************************** # # $Id: permutations.test,v 1.51 2009/07/01 18:09:02 danielk1977 Exp $ set testdir [file dirname $argv0] source $testdir/tester.tcl # Argument processing. # #puts "PERM-DEBUG: argv=$argv" namespace eval ::perm { variable testmode [lindex $::argv 0] variable testfile [lindex $::argv 1] | > | 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 | # #*********************************************************************** # # $Id: permutations.test,v 1.51 2009/07/01 18:09:02 danielk1977 Exp $ set testdir [file dirname $argv0] source $testdir/tester.tcl db close # Argument processing. # #puts "PERM-DEBUG: argv=$argv" namespace eval ::perm { variable testmode [lindex $::argv 0] variable testfile [lindex $::argv 1] |
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Changes to test/wal2.test.
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71 72 73 74 75 76 77 | # of the the integer fields (so that the reader ends up with a corrupted # header). # # 3. Check that the reader recovers the wal-index and reads the correct # database content. # do_test wal2-1.0 { | | > > > > > | 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 | # of the the integer fields (so that the reader ends up with a corrupted # header). # # 3. Check that the reader recovers the wal-index and reads the correct # database content. # do_test wal2-1.0 { proc tvfs_cb {method filename args} { set ::filename $filename return SQLITE_OK } testvfs tvfs tvfs script tvfs_cb tvfs filter xShmOpen sqlite3 db test.db -vfs tvfs sqlite3 db2 test.db -vfs tvfs execsql { PRAGMA journal_mode = WAL; CREATE TABLE t1(a); |
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119 120 121 122 123 124 125 | 10 13 {13 91} 8 {$RECOVER $READ} 11 14 {14 105} 9 {$RECOVER $READ} 12 15 {15 120} -1 {$READ} " { do_test wal2-1.$tn.1 { execsql { INSERT INTO t1 VALUES($iInsert) } | < < < < < < < < < | > > > | | 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 | 10 13 {13 91} 8 {$RECOVER $READ} 11 14 {14 105} 9 {$RECOVER $READ} 12 15 {15 120} -1 {$READ} " { do_test wal2-1.$tn.1 { execsql { INSERT INTO t1 VALUES($iInsert) } set ::locks [list] proc tvfs_cb {method args} { lappend ::locks [lindex $args 2] return SQLITE_OK } tvfs filter xShmLock if {$::wal_index_hdr_mod >= 0} { incr_tvfs_hdr $::filename $::wal_index_hdr_mod 1 } execsql { SELECT count(a), sum(a) FROM t1 } db2 } $res do_test wal2-1.$tn.2 { set ::locks } $wal_locks } |
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170 171 172 173 174 175 176 177 | {4 1 lock exclusive} {4 1 unlock exclusive} \ {4 1 lock shared} {4 1 unlock shared} \ ] do_test wal2-2.0 { testvfs tvfs tvfs script tvfs_cb proc tvfs_cb {method args} { | > | | 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 | {4 1 lock exclusive} {4 1 unlock exclusive} \ {4 1 lock shared} {4 1 unlock shared} \ ] do_test wal2-2.0 { testvfs tvfs tvfs script tvfs_cb tvfs filter xShmOpen proc tvfs_cb {method args} { set ::filename [lindex $args 0] return SQLITE_OK } sqlite3 db test.db -vfs tvfs sqlite3 db2 test.db -vfs tvfs execsql { |
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204 205 206 207 208 209 210 211 | 4 7 {6 21} {7 28} 2 5 8 {7 28} {8 36} 3 6 9 {8 36} {9 45} 4 7 10 {9 45} {10 55} 5 8 11 {10 55} {11 66} 6 9 12 {11 66} {12 78} 7 } { do_test wal2-2.$tn.1 { | > > | < < < < < < < < | | | | < > > > < < < < < < < < | | < > > > | 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 | 4 7 {6 21} {7 28} 2 5 8 {7 28} {8 36} 3 6 9 {8 36} {9 45} 4 7 10 {9 45} {10 55} 5 8 11 {10 55} {11 66} 6 9 12 {11 66} {12 78} 7 } { tvfs filter xShmLock do_test wal2-2.$tn.1 { set oldhdr [set_tvfs_hdr $::filename] execsql { INSERT INTO t1 VALUES($iInsert) } execsql { SELECT count(a), sum(a) FROM t1 } } $res1 do_test wal2-2.$tn.2 { set ::locks [list] proc tvfs_cb {method args} { set lock [lindex $args 2] lappend ::locks $lock if {$lock == $::WRITER} { set_tvfs_hdr $::filename $::oldhdr } return SQLITE_OK } if {$::wal_index_hdr_mod >= 0} { incr_tvfs_hdr $::filename $::wal_index_hdr_mod 1 } execsql { SELECT count(a), sum(a) FROM t1 } db2 } $res0 do_test wal2-2.$tn.3 { set ::locks } $LOCKS do_test wal2-2.$tn.4 { set ::locks [list] proc tvfs_cb {method args} { set lock [lindex $args 2] lappend ::locks $lock return SQLITE_OK } if {$::wal_index_hdr_mod >= 0} { incr_tvfs_hdr $::filename $::wal_index_hdr_mod 1 } execsql { SELECT count(a), sum(a) FROM t1 } db2 } $res1 } db close db2 close tvfs delete file delete -force test.db test.db-wal test.db-journal |
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Changes to test/wal3.test.
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349 350 351 352 353 354 355 | testvfs T -default 1 T script method_callback proc method_callback {method args} { if {$method == "xShmBarrier"} { incr ::barrier_count | | | 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 | testvfs T -default 1 T script method_callback proc method_callback {method args} { if {$method == "xShmBarrier"} { incr ::barrier_count if {$::barrier_count == 2} { # This code is executed within the xShmBarrier() callback invoked # by the client running recovery as part of writing the recovered # wal-index header. If a second client attempts to access the # database now, it reads a corrupt (partially written) wal-index # header. But it cannot even get that far, as the first client # is still holding all the locks (recovery takes an exclusive lock # on *all* db locks, preventing access by any other client). |
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