diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/btree.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/src/btree.c b/src/btree.c index f704baebc..da4666c08 100644 --- a/src/btree.c +++ b/src/btree.c @@ -9,7 +9,7 @@ ** May you share freely, never taking more than you give. ** ************************************************************************* -** $Id: btree.c,v 1.470 2008/06/28 15:33:25 danielk1977 Exp $ +** $Id: btree.c,v 1.471 2008/07/04 17:52:43 drh Exp $ ** ** This file implements a external (disk-based) database using BTrees. ** See the header comment on "btreeInt.h" for additional information. @@ -4051,7 +4051,7 @@ static int allocateBtreePage( *ppPage = pTrunk; pTrunk = 0; TRACE(("ALLOCATE: %d trunk - %d free pages left\n", *pPgno, n-1)); - }else if( k>pBt->usableSize/4 - 8 ){ + }else if( k>pBt->usableSize/4 - 2 ){ /* Value of k is out of range. Database corruption */ rc = SQLITE_CORRUPT_BKPT; goto end_allocate_page; @@ -4271,7 +4271,19 @@ static int freePage(MemPage *pPage){ k = get4byte(&pTrunk->aData[4]); if( k>=pBt->usableSize/4 - 8 ){ /* The trunk is full. Turn the page being freed into a new - ** trunk page with no leaves. */ + ** trunk page with no leaves. + ** + ** Note that the trunk page is not really full until it contains + ** usableSize/4 - 2 entries, not usableSize/4 - 8 entries as we have + ** coded. But due to a coding error in versions of SQLite prior to + ** 3.6.0, databases with freelist trunk pages holding more than + ** usableSize/4 - 8 entries will be reported as corrupt. In order + ** to maintain backwards compatibility with older versions of SQLite, + ** we will contain to restrict the number of entries to usableSize/4 - 8 + ** for now. At some point in the future (once everyone has upgraded + ** to 3.6.0 or later) we should consider fixing the conditional above + ** to read "usableSize/4-2" instead of "usableSize/4-8". + */ rc = sqlite3PagerWrite(pPage->pDbPage); if( rc==SQLITE_OK ){ put4byte(pPage->aData, pTrunk->pgno); @@ -6498,7 +6510,7 @@ static void checkList( checkPtrmap(pCheck, iPage, PTRMAP_FREEPAGE, 0, zContext); } #endif - if( n>pCheck->pBt->usableSize/4-8 ){ + if( n>pCheck->pBt->usableSize/4-2 ){ checkAppendMsg(pCheck, zContext, "freelist leaf count too big on page %d", iPage); N--; |