diff options
Diffstat (limited to 'lib/libsqlite3/src/pager.c')
| -rw-r--r-- | lib/libsqlite3/src/pager.c | 290 |
1 files changed, 153 insertions, 137 deletions
diff --git a/lib/libsqlite3/src/pager.c b/lib/libsqlite3/src/pager.c index a77dcecc4cf..d840a39a159 100644 --- a/lib/libsqlite3/src/pager.c +++ b/lib/libsqlite3/src/pager.c @@ -76,12 +76,12 @@ ** Definition: Two databases (or the same database at two points it time) ** are said to be "logically equivalent" if they give the same answer to ** all queries. Note in particular the content of freelist leaf -** pages can be changed arbitarily without effecting the logical equivalence +** pages can be changed arbitrarily without affecting the logical equivalence ** of the database. ** ** (7) At any time, if any subset, including the empty set and the total set, ** of the unsynced changes to a rollback journal are removed and the -** journal is rolled back, the resulting database file will be logical +** journal is rolled back, the resulting database file will be logically ** equivalent to the database file at the beginning of the transaction. ** ** (8) When a transaction is rolled back, the xTruncate method of the VFS @@ -378,7 +378,7 @@ int sqlite3PagerTrace=1; /* True to enable tracing */ ** ** The exception is when the database file is unlocked as the pager moves ** from ERROR to OPEN state. At this point there may be a hot-journal file -** in the file-system that needs to be rolled back (as part of a OPEN->SHARED +** in the file-system that needs to be rolled back (as part of an OPEN->SHARED ** transition, by the same pager or any other). If the call to xUnlock() ** fails at this point and the pager is left holding an EXCLUSIVE lock, this ** can confuse the call to xCheckReservedLock() call made later as part @@ -461,7 +461,7 @@ struct PagerSavepoint { #define SPILLFLAG_NOSYNC 0x04 /* Spill is ok, but do not sync */ /* -** A open page cache is an instance of struct Pager. A description of +** An open page cache is an instance of struct Pager. A description of ** some of the more important member variables follows: ** ** eState @@ -633,7 +633,7 @@ struct Pager { /************************************************************************** ** The following block contains those class members that change during - ** routine opertion. Class members not in this block are either fixed + ** routine operation. Class members not in this block are either fixed ** when the pager is first created or else only change when there is a ** significant mode change (such as changing the page_size, locking_mode, ** or the journal_mode). From another view, these class members describe @@ -1678,21 +1678,6 @@ static int writeMasterJournal(Pager *pPager, const char *zMaster){ } /* -** Find a page in the hash table given its page number. Return -** a pointer to the page or NULL if the requested page is not -** already in memory. -*/ -static PgHdr *pager_lookup(Pager *pPager, Pgno pgno){ - PgHdr *p = 0; /* Return value */ - - /* It is not possible for a call to PcacheFetch() with createFlag==0 to - ** fail, since no attempt to allocate dynamic memory will be made. - */ - (void)sqlite3PcacheFetch(pPager->pPCache, pgno, 0, &p); - return p; -} - -/* ** Discard the entire contents of the in-memory page-cache. */ static void pager_reset(Pager *pPager){ @@ -1956,6 +1941,14 @@ static int pager_end_transaction(Pager *pPager, int hasMaster, int bCommit){ rc = SQLITE_OK; }else{ rc = sqlite3OsTruncate(pPager->jfd, 0); + if( rc==SQLITE_OK && pPager->fullSync ){ + /* Make sure the new file size is written into the inode right away. + ** Otherwise the journal might resurrect following a power loss and + ** cause the last transaction to roll back. See + ** https://bugzilla.mozilla.org/show_bug.cgi?id=1072773 + */ + rc = sqlite3OsSync(pPager->jfd, pPager->syncFlags); + } } pPager->journalOff = 0; }else if( pPager->journalMode==PAGER_JOURNALMODE_PERSIST @@ -1984,7 +1977,7 @@ static int pager_end_transaction(Pager *pPager, int hasMaster, int bCommit){ #ifdef SQLITE_CHECK_PAGES sqlite3PcacheIterateDirty(pPager->pPCache, pager_set_pagehash); if( pPager->dbSize==0 && sqlite3PcacheRefCount(pPager->pPCache)>0 ){ - PgHdr *p = pager_lookup(pPager, 1); + PgHdr *p = sqlite3PagerLookup(pPager, 1); if( p ){ p->pageHash = 0; sqlite3PagerUnrefNotNull(p); @@ -2263,7 +2256,7 @@ static int pager_playback_one_page( if( pagerUseWal(pPager) ){ pPg = 0; }else{ - pPg = pager_lookup(pPager, pgno); + pPg = sqlite3PagerLookup(pPager, pgno); } assert( pPg || !MEMDB ); assert( pPager->eState!=PAGER_OPEN || pPg==0 ); @@ -2443,7 +2436,7 @@ static int pager_delmaster(Pager *pPager, const char *zMaster){ rc = sqlite3OsFileSize(pMaster, &nMasterJournal); if( rc!=SQLITE_OK ) goto delmaster_out; nMasterPtr = pVfs->mxPathname+1; - zMasterJournal = sqlite3Malloc((int)nMasterJournal + nMasterPtr + 1); + zMasterJournal = sqlite3Malloc(nMasterJournal + nMasterPtr + 1); if( !zMasterJournal ){ rc = SQLITE_NOMEM; goto delmaster_out; @@ -2512,7 +2505,7 @@ delmaster_out: ** If the file on disk is currently larger than nPage pages, then use the VFS ** xTruncate() method to truncate it. ** -** Or, it might might be the case that the file on disk is smaller than +** Or, it might be the case that the file on disk is smaller than ** nPage pages. Some operating system implementations can get confused if ** you try to truncate a file to some size that is larger than it ** currently is, so detect this case and write a single zero byte to @@ -2571,7 +2564,7 @@ int sqlite3SectorSize(sqlite3_file *pFile){ /* ** Set the value of the Pager.sectorSize variable for the given ** pager based on the value returned by the xSectorSize method -** of the open database file. The sector size will be used used +** of the open database file. The sector size will be used ** to determine the size and alignment of journal header and ** master journal pointers within created journal files. ** @@ -3633,11 +3626,15 @@ int sqlite3PagerSetPagesize(Pager *pPager, u32 *pPageSize, int nReserve){ if( rc==SQLITE_OK ){ pager_reset(pPager); - pPager->dbSize = (Pgno)((nByte+pageSize-1)/pageSize); - pPager->pageSize = pageSize; + rc = sqlite3PcacheSetPageSize(pPager->pPCache, pageSize); + } + if( rc==SQLITE_OK ){ sqlite3PageFree(pPager->pTmpSpace); pPager->pTmpSpace = pNew; - sqlite3PcacheSetPageSize(pPager->pPCache, pageSize); + pPager->dbSize = (Pgno)((nByte+pageSize-1)/pageSize); + pPager->pageSize = pageSize; + }else{ + sqlite3PageFree(pNew); } } @@ -3771,7 +3768,7 @@ static int pager_wait_on_lock(Pager *pPager, int locktype){ int rc; /* Return code */ /* Check that this is either a no-op (because the requested lock is - ** already held, or one of the transistions that the busy-handler + ** already held), or one of the transitions that the busy-handler ** may be invoked during, according to the comment above ** sqlite3PagerSetBusyhandler(). */ @@ -4399,8 +4396,8 @@ static int pagerStress(void *p, PgHdr *pPg){ ** a rollback or by user request, respectively. ** ** Spilling is also prohibited when in an error state since that could - ** lead to database corruption. In the current implementaton it - ** is impossible for sqlite3PcacheFetch() to be called with createFlag==1 + ** lead to database corruption. In the current implementation it + ** is impossible for sqlite3PcacheFetch() to be called with createFlag==3 ** while in the error state, hence it is impossible for this routine to ** be called in the error state. Nevertheless, we include a NEVER() ** test for the error state as a safeguard against future changes. @@ -4736,22 +4733,23 @@ act_like_temp_file: testcase( rc!=SQLITE_OK ); } - /* If an error occurred in either of the blocks above, free the - ** Pager structure and close the file. + /* Initialize the PCache object. */ + if( rc==SQLITE_OK ){ + assert( nExtra<1000 ); + nExtra = ROUND8(nExtra); + rc = sqlite3PcacheOpen(szPageDflt, nExtra, !memDb, + !memDb?pagerStress:0, (void *)pPager, pPager->pPCache); + } + + /* If an error occurred above, free the Pager structure and close the file. */ if( rc!=SQLITE_OK ){ - assert( !pPager->pTmpSpace ); sqlite3OsClose(pPager->fd); + sqlite3PageFree(pPager->pTmpSpace); sqlite3_free(pPager); return rc; } - /* Initialize the PCache object. */ - assert( nExtra<1000 ); - nExtra = ROUND8(nExtra); - sqlite3PcacheOpen(szPageDflt, nExtra, !memDb, - !memDb?pagerStress:0, (void *)pPager, pPager->pPCache); - PAGERTRACE(("OPEN %d %s\n", FILEHANDLEID(pPager->fd), pPager->zFilename)); IOTRACE(("OPEN %p %s\n", pPager, pPager->zFilename)) @@ -4938,7 +4936,7 @@ static int hasHotJournal(Pager *pPager, int *pExists){ *pExists = (first!=0); }else if( rc==SQLITE_CANTOPEN ){ /* If we cannot open the rollback journal file in order to see if - ** its has a zero header, that might be due to an I/O error, or + ** it has a zero header, that might be due to an I/O error, or ** it might be due to the race condition described above and in ** ticket #3883. Either way, assume that the journal is hot. ** This might be a false positive. But if it is, then the @@ -5300,7 +5298,6 @@ int sqlite3PagerAcquire( if( pPager->errCode!=SQLITE_OK ){ rc = pPager->errCode; }else{ - if( bMmapOk && pagerUseWal(pPager) ){ rc = sqlite3WalFindFrame(pPager->pWal, pgno, &iFrame); if( rc!=SQLITE_OK ) goto pager_acquire_err; @@ -5315,7 +5312,7 @@ int sqlite3PagerAcquire( if( rc==SQLITE_OK && pData ){ if( pPager->eState>PAGER_READER ){ - (void)sqlite3PcacheFetch(pPager->pPCache, pgno, 0, &pPg); + pPg = sqlite3PagerLookup(pPager, pgno); } if( pPg==0 ){ rc = pagerAcquireMapPage(pPager, pgno, pData, &pPg); @@ -5333,7 +5330,16 @@ int sqlite3PagerAcquire( } } - rc = sqlite3PcacheFetch(pPager->pPCache, pgno, 1, ppPage); + { + sqlite3_pcache_page *pBase; + pBase = sqlite3PcacheFetch(pPager->pPCache, pgno, 3); + if( pBase==0 ){ + rc = sqlite3PcacheFetchStress(pPager->pPCache, pgno, &pBase); + if( rc!=SQLITE_OK ) goto pager_acquire_err; + } + pPg = *ppPage = sqlite3PcacheFetchFinish(pPager->pPCache, pgno, pBase); + if( pPg==0 ) rc = SQLITE_NOMEM; + } } if( rc!=SQLITE_OK ){ @@ -5430,13 +5436,12 @@ pager_acquire_err: ** has ever happened. */ DbPage *sqlite3PagerLookup(Pager *pPager, Pgno pgno){ - PgHdr *pPg = 0; + sqlite3_pcache_page *pPage; assert( pPager!=0 ); assert( pgno!=0 ); assert( pPager->pPCache!=0 ); - assert( pPager->eState>=PAGER_READER && pPager->eState!=PAGER_ERROR ); - sqlite3PcacheFetch(pPager->pPCache, pgno, 0, &pPg); - return pPg; + pPage = sqlite3PcacheFetch(pPager->pPCache, pgno, 0); + return sqlite3PcacheFetchFinish(pPager->pPCache, pgno, pPage); } /* @@ -5773,6 +5778,97 @@ static int pager_write(PgHdr *pPg){ } /* +** This is a variant of sqlite3PagerWrite() that runs when the sector size +** is larger than the page size. SQLite makes the (reasonable) assumption that +** all bytes of a sector are written together by hardware. Hence, all bytes of +** a sector need to be journalled in case of a power loss in the middle of +** a write. +** +** Usually, the sector size is less than or equal to the page size, in which +** case pages can be individually written. This routine only runs in the exceptional +** case where the page size is smaller than the sector size. +*/ +static SQLITE_NOINLINE int pagerWriteLargeSector(PgHdr *pPg){ + int rc = SQLITE_OK; /* Return code */ + Pgno nPageCount; /* Total number of pages in database file */ + Pgno pg1; /* First page of the sector pPg is located on. */ + int nPage = 0; /* Number of pages starting at pg1 to journal */ + int ii; /* Loop counter */ + int needSync = 0; /* True if any page has PGHDR_NEED_SYNC */ + Pager *pPager = pPg->pPager; /* The pager that owns pPg */ + Pgno nPagePerSector = (pPager->sectorSize/pPager->pageSize); + + /* Set the doNotSpill NOSYNC bit to 1. This is because we cannot allow + ** a journal header to be written between the pages journaled by + ** this function. + */ + assert( !MEMDB ); + assert( (pPager->doNotSpill & SPILLFLAG_NOSYNC)==0 ); + pPager->doNotSpill |= SPILLFLAG_NOSYNC; + + /* This trick assumes that both the page-size and sector-size are + ** an integer power of 2. It sets variable pg1 to the identifier + ** of the first page of the sector pPg is located on. + */ + pg1 = ((pPg->pgno-1) & ~(nPagePerSector-1)) + 1; + + nPageCount = pPager->dbSize; + if( pPg->pgno>nPageCount ){ + nPage = (pPg->pgno - pg1)+1; + }else if( (pg1+nPagePerSector-1)>nPageCount ){ + nPage = nPageCount+1-pg1; + }else{ + nPage = nPagePerSector; + } + assert(nPage>0); + assert(pg1<=pPg->pgno); + assert((pg1+nPage)>pPg->pgno); + + for(ii=0; ii<nPage && rc==SQLITE_OK; ii++){ + Pgno pg = pg1+ii; + PgHdr *pPage; + if( pg==pPg->pgno || !sqlite3BitvecTest(pPager->pInJournal, pg) ){ + if( pg!=PAGER_MJ_PGNO(pPager) ){ + rc = sqlite3PagerGet(pPager, pg, &pPage); + if( rc==SQLITE_OK ){ + rc = pager_write(pPage); + if( pPage->flags&PGHDR_NEED_SYNC ){ + needSync = 1; + } + sqlite3PagerUnrefNotNull(pPage); + } + } + }else if( (pPage = sqlite3PagerLookup(pPager, pg))!=0 ){ + if( pPage->flags&PGHDR_NEED_SYNC ){ + needSync = 1; + } + sqlite3PagerUnrefNotNull(pPage); + } + } + + /* If the PGHDR_NEED_SYNC flag is set for any of the nPage pages + ** starting at pg1, then it needs to be set for all of them. Because + ** writing to any of these nPage pages may damage the others, the + ** journal file must contain sync()ed copies of all of them + ** before any of them can be written out to the database file. + */ + if( rc==SQLITE_OK && needSync ){ + assert( !MEMDB ); + for(ii=0; ii<nPage; ii++){ + PgHdr *pPage = sqlite3PagerLookup(pPager, pg1+ii); + if( pPage ){ + pPage->flags |= PGHDR_NEED_SYNC; + sqlite3PagerUnrefNotNull(pPage); + } + } + } + + assert( (pPager->doNotSpill & SPILLFLAG_NOSYNC)!=0 ); + pPager->doNotSpill &= ~SPILLFLAG_NOSYNC; + return rc; +} + +/* ** Mark a data page as writeable. This routine must be called before ** making changes to a page. The caller must check the return value ** of this function and be careful not to change any page data unless @@ -5786,96 +5882,16 @@ static int pager_write(PgHdr *pPg){ ** If an error occurs, SQLITE_NOMEM or an IO error code is returned ** as appropriate. Otherwise, SQLITE_OK. */ -int sqlite3PagerWrite(DbPage *pDbPage){ - int rc = SQLITE_OK; - - PgHdr *pPg = pDbPage; - Pager *pPager = pPg->pPager; - +int sqlite3PagerWrite(PgHdr *pPg){ assert( (pPg->flags & PGHDR_MMAP)==0 ); - assert( pPager->eState>=PAGER_WRITER_LOCKED ); - assert( pPager->eState!=PAGER_ERROR ); - assert( assert_pager_state(pPager) ); - - if( pPager->sectorSize > (u32)pPager->pageSize ){ - Pgno nPageCount; /* Total number of pages in database file */ - Pgno pg1; /* First page of the sector pPg is located on. */ - int nPage = 0; /* Number of pages starting at pg1 to journal */ - int ii; /* Loop counter */ - int needSync = 0; /* True if any page has PGHDR_NEED_SYNC */ - Pgno nPagePerSector = (pPager->sectorSize/pPager->pageSize); - - /* Set the doNotSpill NOSYNC bit to 1. This is because we cannot allow - ** a journal header to be written between the pages journaled by - ** this function. - */ - assert( !MEMDB ); - assert( (pPager->doNotSpill & SPILLFLAG_NOSYNC)==0 ); - pPager->doNotSpill |= SPILLFLAG_NOSYNC; - - /* This trick assumes that both the page-size and sector-size are - ** an integer power of 2. It sets variable pg1 to the identifier - ** of the first page of the sector pPg is located on. - */ - pg1 = ((pPg->pgno-1) & ~(nPagePerSector-1)) + 1; - - nPageCount = pPager->dbSize; - if( pPg->pgno>nPageCount ){ - nPage = (pPg->pgno - pg1)+1; - }else if( (pg1+nPagePerSector-1)>nPageCount ){ - nPage = nPageCount+1-pg1; - }else{ - nPage = nPagePerSector; - } - assert(nPage>0); - assert(pg1<=pPg->pgno); - assert((pg1+nPage)>pPg->pgno); - - for(ii=0; ii<nPage && rc==SQLITE_OK; ii++){ - Pgno pg = pg1+ii; - PgHdr *pPage; - if( pg==pPg->pgno || !sqlite3BitvecTest(pPager->pInJournal, pg) ){ - if( pg!=PAGER_MJ_PGNO(pPager) ){ - rc = sqlite3PagerGet(pPager, pg, &pPage); - if( rc==SQLITE_OK ){ - rc = pager_write(pPage); - if( pPage->flags&PGHDR_NEED_SYNC ){ - needSync = 1; - } - sqlite3PagerUnrefNotNull(pPage); - } - } - }else if( (pPage = pager_lookup(pPager, pg))!=0 ){ - if( pPage->flags&PGHDR_NEED_SYNC ){ - needSync = 1; - } - sqlite3PagerUnrefNotNull(pPage); - } - } - - /* If the PGHDR_NEED_SYNC flag is set for any of the nPage pages - ** starting at pg1, then it needs to be set for all of them. Because - ** writing to any of these nPage pages may damage the others, the - ** journal file must contain sync()ed copies of all of them - ** before any of them can be written out to the database file. - */ - if( rc==SQLITE_OK && needSync ){ - assert( !MEMDB ); - for(ii=0; ii<nPage; ii++){ - PgHdr *pPage = pager_lookup(pPager, pg1+ii); - if( pPage ){ - pPage->flags |= PGHDR_NEED_SYNC; - sqlite3PagerUnrefNotNull(pPage); - } - } - } - - assert( (pPager->doNotSpill & SPILLFLAG_NOSYNC)!=0 ); - pPager->doNotSpill &= ~SPILLFLAG_NOSYNC; + assert( pPg->pPager->eState>=PAGER_WRITER_LOCKED ); + assert( pPg->pPager->eState!=PAGER_ERROR ); + assert( assert_pager_state(pPg->pPager) ); + if( pPg->pPager->sectorSize > (u32)pPg->pPager->pageSize ){ + return pagerWriteLargeSector(pPg); }else{ - rc = pager_write(pDbPage); + return pager_write(pPg); } - return rc; } /* @@ -6771,7 +6787,7 @@ int sqlite3PagerMovepage(Pager *pPager, DbPage *pPg, Pgno pgno, int isCommit){ ** for the page moved there. */ pPg->flags &= ~PGHDR_NEED_SYNC; - pPgOld = pager_lookup(pPager, pgno); + pPgOld = sqlite3PagerLookup(pPager, pgno); assert( !pPgOld || pPgOld->nRef==1 ); if( pPgOld ){ pPg->flags |= (pPgOld->flags&PGHDR_NEED_SYNC); @@ -7224,7 +7240,7 @@ int sqlite3PagerCloseWal(Pager *pPager){ ** is empty, return 0. */ int sqlite3PagerWalFramesize(Pager *pPager){ - assert( pPager->eState==PAGER_READER ); + assert( pPager->eState>=PAGER_READER ); return sqlite3WalFramesize(pPager->pWal); } #endif |