diff options
Diffstat (limited to 'src/backup.c')
-rw-r--r-- | src/backup.c | 180 |
1 files changed, 92 insertions, 88 deletions
diff --git a/src/backup.c b/src/backup.c index 4d7ae3183..70a782665 100644 --- a/src/backup.c +++ b/src/backup.c @@ -410,102 +410,106 @@ int sqlite3_backup_step(sqlite3_backup *p, int nPage){ ** the case where the source and destination databases have the ** same schema version. */ - if( rc==SQLITE_DONE - && (rc = sqlite3BtreeUpdateMeta(p->pDest,1,p->iDestSchema+1))==SQLITE_OK - ){ - int nDestTruncate; - - if( p->pDestDb ){ - sqlite3ResetInternalSchema(p->pDestDb, -1); - } - - /* Set nDestTruncate to the final number of pages in the destination - ** database. The complication here is that the destination page - ** size may be different to the source page size. - ** - ** If the source page size is smaller than the destination page size, - ** round up. In this case the call to sqlite3OsTruncate() below will - ** fix the size of the file. However it is important to call - ** sqlite3PagerTruncateImage() here so that any pages in the - ** destination file that lie beyond the nDestTruncate page mark are - ** journalled by PagerCommitPhaseOne() before they are destroyed - ** by the file truncation. - */ - assert( pgszSrc==sqlite3BtreeGetPageSize(p->pSrc) ); - assert( pgszDest==sqlite3BtreeGetPageSize(p->pDest) ); - if( pgszSrc<pgszDest ){ - int ratio = pgszDest/pgszSrc; - nDestTruncate = (nSrcPage+ratio-1)/ratio; - if( nDestTruncate==(int)PENDING_BYTE_PAGE(p->pDest->pBt) ){ - nDestTruncate--; + if( rc==SQLITE_DONE ){ + rc = sqlite3BtreeUpdateMeta(p->pDest,1,p->iDestSchema+1); + if( rc==SQLITE_OK ){ + if( p->pDestDb ){ + sqlite3ResetInternalSchema(p->pDestDb, -1); + } + if( destMode==PAGER_JOURNALMODE_WAL ){ + rc = sqlite3BtreeSetVersion(p->pDest, 2); } - }else{ - nDestTruncate = nSrcPage * (pgszSrc/pgszDest); } - sqlite3PagerTruncateImage(pDestPager, nDestTruncate); - - if( pgszSrc<pgszDest ){ - /* If the source page-size is smaller than the destination page-size, - ** two extra things may need to happen: - ** - ** * The destination may need to be truncated, and + if( rc==SQLITE_OK ){ + int nDestTruncate; + /* Set nDestTruncate to the final number of pages in the destination + ** database. The complication here is that the destination page + ** size may be different to the source page size. ** - ** * Data stored on the pages immediately following the - ** pending-byte page in the source database may need to be - ** copied into the destination database. + ** If the source page size is smaller than the destination page size, + ** round up. In this case the call to sqlite3OsTruncate() below will + ** fix the size of the file. However it is important to call + ** sqlite3PagerTruncateImage() here so that any pages in the + ** destination file that lie beyond the nDestTruncate page mark are + ** journalled by PagerCommitPhaseOne() before they are destroyed + ** by the file truncation. */ - const i64 iSize = (i64)pgszSrc * (i64)nSrcPage; - sqlite3_file * const pFile = sqlite3PagerFile(pDestPager); - i64 iOff; - i64 iEnd; - - assert( pFile ); - assert( (i64)nDestTruncate*(i64)pgszDest >= iSize || ( - nDestTruncate==(int)(PENDING_BYTE_PAGE(p->pDest->pBt)-1) - && iSize>=PENDING_BYTE && iSize<=PENDING_BYTE+pgszDest - )); - - /* This call ensures that all data required to recreate the original - ** database has been stored in the journal for pDestPager and the - ** journal synced to disk. So at this point we may safely modify - ** the database file in any way, knowing that if a power failure - ** occurs, the original database will be reconstructed from the - ** journal file. */ - rc = sqlite3PagerCommitPhaseOne(pDestPager, 0, 1); - - /* Write the extra pages and truncate the database file as required. */ - iEnd = MIN(PENDING_BYTE + pgszDest, iSize); - for( - iOff=PENDING_BYTE+pgszSrc; - rc==SQLITE_OK && iOff<iEnd; - iOff+=pgszSrc - ){ - PgHdr *pSrcPg = 0; - const Pgno iSrcPg = (Pgno)((iOff/pgszSrc)+1); - rc = sqlite3PagerGet(pSrcPager, iSrcPg, &pSrcPg); - if( rc==SQLITE_OK ){ - u8 *zData = sqlite3PagerGetData(pSrcPg); - rc = sqlite3OsWrite(pFile, zData, pgszSrc, iOff); + assert( pgszSrc==sqlite3BtreeGetPageSize(p->pSrc) ); + assert( pgszDest==sqlite3BtreeGetPageSize(p->pDest) ); + if( pgszSrc<pgszDest ){ + int ratio = pgszDest/pgszSrc; + nDestTruncate = (nSrcPage+ratio-1)/ratio; + if( nDestTruncate==(int)PENDING_BYTE_PAGE(p->pDest->pBt) ){ + nDestTruncate--; } - sqlite3PagerUnref(pSrcPg); - } - if( rc==SQLITE_OK ){ - rc = backupTruncateFile(pFile, iSize); + }else{ + nDestTruncate = nSrcPage * (pgszSrc/pgszDest); } + sqlite3PagerTruncateImage(pDestPager, nDestTruncate); + + if( pgszSrc<pgszDest ){ + /* If the source page-size is smaller than the destination page-size, + ** two extra things may need to happen: + ** + ** * The destination may need to be truncated, and + ** + ** * Data stored on the pages immediately following the + ** pending-byte page in the source database may need to be + ** copied into the destination database. + */ + const i64 iSize = (i64)pgszSrc * (i64)nSrcPage; + sqlite3_file * const pFile = sqlite3PagerFile(pDestPager); + i64 iOff; + i64 iEnd; + + assert( pFile ); + assert( (i64)nDestTruncate*(i64)pgszDest >= iSize || ( + nDestTruncate==(int)(PENDING_BYTE_PAGE(p->pDest->pBt)-1) + && iSize>=PENDING_BYTE && iSize<=PENDING_BYTE+pgszDest + )); + + /* This call ensures that all data required to recreate the original + ** database has been stored in the journal for pDestPager and the + ** journal synced to disk. So at this point we may safely modify + ** the database file in any way, knowing that if a power failure + ** occurs, the original database will be reconstructed from the + ** journal file. */ + rc = sqlite3PagerCommitPhaseOne(pDestPager, 0, 1); + + /* Write the extra pages and truncate the database file as required */ + iEnd = MIN(PENDING_BYTE + pgszDest, iSize); + for( + iOff=PENDING_BYTE+pgszSrc; + rc==SQLITE_OK && iOff<iEnd; + iOff+=pgszSrc + ){ + PgHdr *pSrcPg = 0; + const Pgno iSrcPg = (Pgno)((iOff/pgszSrc)+1); + rc = sqlite3PagerGet(pSrcPager, iSrcPg, &pSrcPg); + if( rc==SQLITE_OK ){ + u8 *zData = sqlite3PagerGetData(pSrcPg); + rc = sqlite3OsWrite(pFile, zData, pgszSrc, iOff); + } + sqlite3PagerUnref(pSrcPg); + } + if( rc==SQLITE_OK ){ + rc = backupTruncateFile(pFile, iSize); + } - /* Sync the database file to disk. */ - if( rc==SQLITE_OK ){ - rc = sqlite3PagerSync(pDestPager); + /* Sync the database file to disk. */ + if( rc==SQLITE_OK ){ + rc = sqlite3PagerSync(pDestPager); + } + }else{ + rc = sqlite3PagerCommitPhaseOne(pDestPager, 0, 0); + } + + /* Finish committing the transaction to the destination database. */ + if( SQLITE_OK==rc + && SQLITE_OK==(rc = sqlite3BtreeCommitPhaseTwo(p->pDest, 0)) + ){ + rc = SQLITE_DONE; } - }else{ - rc = sqlite3PagerCommitPhaseOne(pDestPager, 0, 0); - } - - /* Finish committing the transaction to the destination database. */ - if( SQLITE_OK==rc - && SQLITE_OK==(rc = sqlite3BtreeCommitPhaseTwo(p->pDest, 0)) - ){ - rc = SQLITE_DONE; } } |