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Diffstat (limited to 'src/btree.c')
-rw-r--r--src/btree.c81
1 files changed, 35 insertions, 46 deletions
diff --git a/src/btree.c b/src/btree.c
index facb951d3..80bca6635 100644
--- a/src/btree.c
+++ b/src/btree.c
@@ -1513,7 +1513,6 @@ static int defragmentPage(MemPage *pPage, int nMaxFrag){
assert( pPage->pBt->usableSize <= SQLITE_MAX_PAGE_SIZE );
assert( pPage->nOverflow==0 );
assert( sqlite3_mutex_held(pPage->pBt->mutex) );
- temp = 0;
src = data = pPage->aData;
hdr = pPage->hdrOffset;
cellOffset = pPage->cellOffset;
@@ -1568,39 +1567,38 @@ static int defragmentPage(MemPage *pPage, int nMaxFrag){
cbrk = usableSize;
iCellLast = usableSize - 4;
iCellStart = get2byte(&data[hdr+5]);
- for(i=0; i<nCell; i++){
- u8 *pAddr; /* The i-th cell pointer */
- pAddr = &data[cellOffset + i*2];
- pc = get2byte(pAddr);
- testcase( pc==iCellFirst );
- testcase( pc==iCellLast );
- /* These conditions have already been verified in btreeInitPage()
- ** if PRAGMA cell_size_check=ON.
- */
- if( pc<iCellStart || pc>iCellLast ){
- return SQLITE_CORRUPT_PAGE(pPage);
- }
- assert( pc>=iCellStart && pc<=iCellLast );
- size = pPage->xCellSize(pPage, &src[pc]);
- cbrk -= size;
- if( cbrk<iCellStart || pc+size>usableSize ){
- return SQLITE_CORRUPT_PAGE(pPage);
- }
- assert( cbrk+size<=usableSize && cbrk>=iCellStart );
- testcase( cbrk+size==usableSize );
- testcase( pc+size==usableSize );
- put2byte(pAddr, cbrk);
- if( temp==0 ){
- if( cbrk==pc ) continue;
- temp = sqlite3PagerTempSpace(pPage->pBt->pPager);
- memcpy(&temp[iCellStart], &data[iCellStart], usableSize - iCellStart);
- src = temp;
+ if( nCell>0 ){
+ temp = sqlite3PagerTempSpace(pPage->pBt->pPager);
+ memcpy(&temp[iCellStart], &data[iCellStart], usableSize - iCellStart);
+ src = temp;
+ for(i=0; i<nCell; i++){
+ u8 *pAddr; /* The i-th cell pointer */
+ pAddr = &data[cellOffset + i*2];
+ pc = get2byte(pAddr);
+ testcase( pc==iCellFirst );
+ testcase( pc==iCellLast );
+ /* These conditions have already been verified in btreeInitPage()
+ ** if PRAGMA cell_size_check=ON.
+ */
+ if( pc<iCellStart || pc>iCellLast ){
+ return SQLITE_CORRUPT_PAGE(pPage);
+ }
+ assert( pc>=iCellStart && pc<=iCellLast );
+ size = pPage->xCellSize(pPage, &src[pc]);
+ cbrk -= size;
+ if( cbrk<iCellStart || pc+size>usableSize ){
+ return SQLITE_CORRUPT_PAGE(pPage);
+ }
+ assert( cbrk+size<=usableSize && cbrk>=iCellStart );
+ testcase( cbrk+size==usableSize );
+ testcase( pc+size==usableSize );
+ put2byte(pAddr, cbrk);
+ memcpy(&data[cbrk], &src[pc], size);
}
- memcpy(&data[cbrk], &src[pc], size);
}
data[hdr+7] = 0;
- defragment_out:
+defragment_out:
assert( pPage->nFree>=0 );
if( data[hdr+7]+cbrk-iCellFirst!=pPage->nFree ){
return SQLITE_CORRUPT_PAGE(pPage);
@@ -1673,9 +1671,9 @@ static u8 *pageFindSlot(MemPage *pPg, int nByte, int *pRc){
iAddr = pc;
pTmp = &aData[pc];
pc = get2byte(pTmp);
- if( pc<=iAddr+size ){
+ if( pc<=iAddr ){
if( pc ){
- /* The next slot in the chain is not past the end of the current slot */
+ /* The next slot in the chain comes before the current slot */
*pRc = SQLITE_CORRUPT_PAGE(pPg);
}
return 0;
@@ -1827,7 +1825,7 @@ static int freeSpace(MemPage *pPage, u16 iStart, u16 iSize){
iFreeBlk = 0; /* Shortcut for the case when the freelist is empty */
}else{
while( (iFreeBlk = get2byte(&data[iPtr]))<iStart ){
- if( iFreeBlk<iPtr+4 ){
+ if( iFreeBlk<=iPtr ){
if( iFreeBlk==0 ) break; /* TH3: corrupt082.100 */
return SQLITE_CORRUPT_PAGE(pPage);
}
@@ -2309,9 +2307,7 @@ getAndInitPage_error1:
pCur->pPage = pCur->apPage[pCur->iPage];
}
testcase( pgno==0 );
- assert( pgno!=0 || rc==SQLITE_CORRUPT
- || rc==SQLITE_IOERR_NOMEM
- || rc==SQLITE_NOMEM );
+ assert( pgno!=0 || rc!=SQLITE_OK );
return rc;
}
@@ -5253,8 +5249,6 @@ const void *sqlite3BtreePayloadFetch(BtCursor *pCur, u32 *pAmt){
** vice-versa).
*/
static int moveToChild(BtCursor *pCur, u32 newPgno){
- BtShared *pBt = pCur->pBt;
-
assert( cursorOwnsBtShared(pCur) );
assert( pCur->eState==CURSOR_VALID );
assert( pCur->iPage<BTCURSOR_MAX_DEPTH );
@@ -5268,7 +5262,8 @@ static int moveToChild(BtCursor *pCur, u32 newPgno){
pCur->apPage[pCur->iPage] = pCur->pPage;
pCur->ix = 0;
pCur->iPage++;
- return getAndInitPage(pBt, newPgno, &pCur->pPage, pCur, pCur->curPagerFlags);
+ return getAndInitPage(pCur->pBt, newPgno, &pCur->pPage, pCur,
+ pCur->curPagerFlags);
}
#ifdef SQLITE_DEBUG
@@ -5374,7 +5369,7 @@ static int moveToRoot(BtCursor *pCur){
}
sqlite3BtreeClearCursor(pCur);
}
- rc = getAndInitPage(pCur->pBtree->pBt, pCur->pgnoRoot, &pCur->pPage,
+ rc = getAndInitPage(pCur->pBt, pCur->pgnoRoot, &pCur->pPage,
0, pCur->curPagerFlags);
if( rc!=SQLITE_OK ){
pCur->eState = CURSOR_INVALID;
@@ -7015,12 +7010,6 @@ static void dropCell(MemPage *pPage, int idx, int sz, int *pRC){
assert( pPage->pBt->usableSize > (u32)(ptr-data) );
pc = get2byte(ptr);
hdr = pPage->hdrOffset;
-#if 0 /* Not required. Omit for efficiency */
- if( pc<hdr+pPage->nCell*2 ){
- *pRC = SQLITE_CORRUPT_BKPT;
- return;
- }
-#endif
testcase( pc==(u32)get2byte(&data[hdr+5]) );
testcase( pc+sz==pPage->pBt->usableSize );
if( pc+sz > pPage->pBt->usableSize ){