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-rw-r--r--src/backup.c175
1 files changed, 85 insertions, 90 deletions
diff --git a/src/backup.c b/src/backup.c
index 83fa74767..9a43f670c 100644
--- a/src/backup.c
+++ b/src/backup.c
@@ -413,108 +413,103 @@ int sqlite3_backup_step(sqlite3_backup *p, int nPage){
if( rc==SQLITE_DONE
&& (rc = sqlite3BtreeUpdateMeta(p->pDest,1,p->iDestSchema+1))==SQLITE_OK
){
- int nDestTruncate;
-
if( p->pDestDb ){
sqlite3ResetInternalSchema(p->pDestDb, -1);
}
-
if( destMode==PAGER_JOURNALMODE_WAL ){
- /* This call cannot fail. The success of the BtreeUpdateMeta()
- ** method above indicates that a write transaction has been opened
- ** and page 1 is already dirty. Therefore this always succeeds.
- */
- TESTONLY(int rc2 =) sqlite3BtreeSetVersion(p->pDest, 2);
- assert( rc2==SQLITE_OK );
- }
-
- /* 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--;
- }
- }else{
- nDestTruncate = nSrcPage * (pgszSrc/pgszDest);
+ rc = sqlite3BtreeSetVersion(p->pDest, 2);
}
- 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;
}
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-07-19 13:20:49 +0000