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-rw-r--r--src/btree.c759
1 files changed, 402 insertions, 357 deletions
diff --git a/src/btree.c b/src/btree.c
index 3ca6058..60bc7de 100644
--- a/src/btree.c
+++ b/src/btree.c
@@ -162,7 +162,7 @@ static int hasSharedCacheTableLock(
** the correct locks are held. So do not bother - just return true.
** This case does not come up very often anyhow.
*/
- if( isIndex && (!pSchema || (pSchema->flags&DB_SchemaLoaded)==0) ){
+ if( isIndex && (!pSchema || (pSchema->schemaFlags&DB_SchemaLoaded)==0) ){
return 1;
}
@@ -446,16 +446,11 @@ static int cursorHoldsMutex(BtCursor *p){
}
#endif
-
-#ifndef SQLITE_OMIT_INCRBLOB
/*
-** Invalidate the overflow page-list cache for cursor pCur, if any.
+** Invalidate the overflow cache of the cursor passed as the first argument.
+** on the shared btree structure pBt.
*/
-static void invalidateOverflowCache(BtCursor *pCur){
- assert( cursorHoldsMutex(pCur) );
- sqlite3_free(pCur->aOverflow);
- pCur->aOverflow = 0;
-}
+#define invalidateOverflowCache(pCur) (pCur->curFlags &= ~BTCF_ValidOvfl)
/*
** Invalidate the overflow page-list cache for all cursors opened
@@ -469,6 +464,7 @@ static void invalidateAllOverflowCache(BtShared *pBt){
}
}
+#ifndef SQLITE_OMIT_INCRBLOB
/*
** This function is called before modifying the contents of a table
** to invalidate any incrblob cursors that are open on the
@@ -491,16 +487,14 @@ static void invalidateIncrblobCursors(
BtShared *pBt = pBtree->pBt;
assert( sqlite3BtreeHoldsMutex(pBtree) );
for(p=pBt->pCursor; p; p=p->pNext){
- if( p->isIncrblobHandle && (isClearTable || p->info.nKey==iRow) ){
+ if( (p->curFlags & BTCF_Incrblob)!=0 && (isClearTable || p->info.nKey==iRow) ){
p->eState = CURSOR_INVALID;
}
}
}
#else
- /* Stub functions when INCRBLOB is omitted */
- #define invalidateOverflowCache(x)
- #define invalidateAllOverflowCache(x)
+ /* Stub function when INCRBLOB is omitted */
#define invalidateIncrblobCursors(x,y,z)
#endif /* SQLITE_OMIT_INCRBLOB */
@@ -684,7 +678,7 @@ static int btreeMoveto(
){
int rc; /* Status code */
UnpackedRecord *pIdxKey; /* Unpacked index key */
- char aSpace[150]; /* Temp space for pIdxKey - to avoid a malloc */
+ char aSpace[200]; /* Temp space for pIdxKey - to avoid a malloc */
char *pFree = 0;
if( pKey ){
@@ -694,6 +688,10 @@ static int btreeMoveto(
);
if( pIdxKey==0 ) return SQLITE_NOMEM;
sqlite3VdbeRecordUnpack(pCur->pKeyInfo, (int)nKey, pKey, pIdxKey);
+ if( pIdxKey->nField==0 ){
+ sqlite3DbFree(pCur->pKeyInfo->db, pFree);
+ return SQLITE_CORRUPT_BKPT;
+ }
}else{
pIdxKey = 0;
}
@@ -724,6 +722,9 @@ static int btreeRestoreCursorPosition(BtCursor *pCur){
sqlite3_free(pCur->pKey);
pCur->pKey = 0;
assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_INVALID );
+ if( pCur->skipNext && pCur->eState==CURSOR_VALID ){
+ pCur->eState = CURSOR_SKIPNEXT;
+ }
}
return rc;
}
@@ -739,20 +740,32 @@ static int btreeRestoreCursorPosition(BtCursor *pCur){
** at is deleted out from under them.
**
** This routine returns an error code if something goes wrong. The
-** integer *pHasMoved is set to one if the cursor has moved and 0 if not.
+** integer *pHasMoved is set as follows:
+**
+** 0: The cursor is unchanged
+** 1: The cursor is still pointing at the same row, but the pointers
+** returned by sqlite3BtreeKeyFetch() or sqlite3BtreeDataFetch()
+** might now be invalid because of a balance() or other change to the
+** b-tree.
+** 2: The cursor is no longer pointing to the row. The row might have
+** been deleted out from under the cursor.
*/
int sqlite3BtreeCursorHasMoved(BtCursor *pCur, int *pHasMoved){
int rc;
+ if( pCur->eState==CURSOR_VALID ){
+ *pHasMoved = 0;
+ return SQLITE_OK;
+ }
rc = restoreCursorPosition(pCur);
if( rc ){
- *pHasMoved = 1;
+ *pHasMoved = 2;
return rc;
}
- if( pCur->eState!=CURSOR_VALID || pCur->skipNext!=0 ){
- *pHasMoved = 1;
+ if( pCur->eState!=CURSOR_VALID || NEVER(pCur->skipNext!=0) ){
+ *pHasMoved = 2;
}else{
- *pHasMoved = 0;
+ *pHasMoved = 1;
}
return SQLITE_OK;
}
@@ -937,7 +950,8 @@ static void btreeParseCellPtr(
assert( n==4-4*pPage->leaf );
if( pPage->intKey ){
if( pPage->hasData ){
- n += getVarint32(&pCell[n], nPayload);
+ assert( n==0 );
+ n = getVarint32(pCell, nPayload);
}else{
nPayload = 0;
}
@@ -1215,7 +1229,7 @@ static int allocateSpace(MemPage *pPage, int nByte, int *pIdx){
}else if( gap+2<=top ){
/* Search the freelist looking for a free slot big enough to satisfy
** the request. The allocation is made from the first free slot in
- ** the list that is large enough to accomadate it.
+ ** the list that is large enough to accommodate it.
*/
int pc, addr;
for(addr=hdr+1; (pc = get2byte(&data[addr]))>0; addr=pc){
@@ -1534,13 +1548,12 @@ static void zeroPage(MemPage *pPage, int flags){
memset(&data[hdr], 0, pBt->usableSize - hdr);
}
data[hdr] = (char)flags;
- first = hdr + 8 + 4*((flags&PTF_LEAF)==0 ?1:0);
+ first = hdr + ((flags&PTF_LEAF)==0 ? 12 : 8);
memset(&data[hdr+1], 0, 4);
data[hdr+7] = 0;
put2byte(&data[hdr+5], pBt->usableSize);
pPage->nFree = (u16)(pBt->usableSize - first);
decodeFlags(pPage, flags);
- pPage->hdrOffset = hdr;
pPage->cellOffset = first;
pPage->aDataEnd = &data[pBt->usableSize];
pPage->aCellIdx = &data[first];
@@ -1581,15 +1594,12 @@ static int btreeGetPage(
BtShared *pBt, /* The btree */
Pgno pgno, /* Number of the page to fetch */
MemPage **ppPage, /* Return the page in this parameter */
- int noContent, /* Do not load page content if true */
- int bReadonly /* True if a read-only (mmap) page is ok */
+ int flags /* PAGER_GET_NOCONTENT or PAGER_GET_READONLY */
){
int rc;
DbPage *pDbPage;
- int flags = (noContent ? PAGER_ACQUIRE_NOCONTENT : 0)
- | (bReadonly ? PAGER_ACQUIRE_READONLY : 0);
- assert( noContent==0 || bReadonly==0 );
+ assert( flags==0 || flags==PAGER_GET_NOCONTENT || flags==PAGER_GET_READONLY );
assert( sqlite3_mutex_held(pBt->mutex) );
rc = sqlite3PagerAcquire(pBt->pPager, pgno, (DbPage**)&pDbPage, flags);
if( rc ) return rc;
@@ -1622,7 +1632,7 @@ static Pgno btreePagecount(BtShared *pBt){
u32 sqlite3BtreeLastPage(Btree *p){
assert( sqlite3BtreeHoldsMutex(p) );
assert( ((p->pBt->nPage)&0x8000000)==0 );
- return (int)btreePagecount(p->pBt);
+ return btreePagecount(p->pBt);
}
/*
@@ -1637,16 +1647,17 @@ static int getAndInitPage(
BtShared *pBt, /* The database file */
Pgno pgno, /* Number of the page to get */
MemPage **ppPage, /* Write the page pointer here */
- int bReadonly /* True if a read-only (mmap) page is ok */
+ int bReadonly /* PAGER_GET_READONLY or 0 */
){
int rc;
assert( sqlite3_mutex_held(pBt->mutex) );
+ assert( bReadonly==PAGER_GET_READONLY || bReadonly==0 );
if( pgno>btreePagecount(pBt) ){
rc = SQLITE_CORRUPT_BKPT;
}else{
- rc = btreeGetPage(pBt, pgno, ppPage, 0, bReadonly);
- if( rc==SQLITE_OK ){
+ rc = btreeGetPage(pBt, pgno, ppPage, bReadonly);
+ if( rc==SQLITE_OK && (*ppPage)->isInit==0 ){
rc = btreeInitPage(*ppPage);
if( rc!=SQLITE_OK ){
releasePage(*ppPage);
@@ -1667,10 +1678,11 @@ static void releasePage(MemPage *pPage){
if( pPage ){
assert( pPage->aData );
assert( pPage->pBt );
+ assert( pPage->pDbPage!=0 );
assert( sqlite3PagerGetExtra(pPage->pDbPage) == (void*)pPage );
assert( sqlite3PagerGetData(pPage->pDbPage)==pPage->aData );
assert( sqlite3_mutex_held(pPage->pBt->mutex) );
- sqlite3PagerUnref(pPage->pDbPage);
+ sqlite3PagerUnrefNotNull(pPage->pDbPage);
}
}
@@ -2050,6 +2062,18 @@ static int removeFromSharingList(BtShared *pBt){
static void allocateTempSpace(BtShared *pBt){
if( !pBt->pTmpSpace ){
pBt->pTmpSpace = sqlite3PageMalloc( pBt->pageSize );
+
+ /* One of the uses of pBt->pTmpSpace is to format cells before
+ ** inserting them into a leaf page (function fillInCell()). If
+ ** a cell is less than 4 bytes in size, it is rounded up to 4 bytes
+ ** by the various routines that manipulate binary cells. Which
+ ** can mean that fillInCell() only initializes the first 2 or 3
+ ** bytes of pTmpSpace, but that the first 4 bytes are copied from
+ ** it into a database page. This is not actually a problem, but it
+ ** does cause a valgrind error when the 1 or 2 bytes of unitialized
+ ** data is passed to system call write(). So to avoid this error,
+ ** zero the first 4 bytes of temp space here. */
+ if( pBt->pTmpSpace ) memset(pBt->pTmpSpace, 0, 4);
}
}
@@ -2143,6 +2167,7 @@ int sqlite3BtreeSetCacheSize(Btree *p, int mxPage){
return SQLITE_OK;
}
+#if SQLITE_MAX_MMAP_SIZE>0
/*
** Change the limit on the amount of the database file that may be
** memory mapped.
@@ -2155,6 +2180,7 @@ int sqlite3BtreeSetMmapLimit(Btree *p, sqlite3_int64 szMmap){
sqlite3BtreeLeave(p);
return SQLITE_OK;
}
+#endif /* SQLITE_MAX_MMAP_SIZE>0 */
/*
** Change the way data is synced to disk in order to increase or decrease
@@ -2165,17 +2191,14 @@ int sqlite3BtreeSetMmapLimit(Btree *p, sqlite3_int64 szMmap){
** probability of damage to near zero but with a write performance reduction.
*/
#ifndef SQLITE_OMIT_PAGER_PRAGMAS
-int sqlite3BtreeSetSafetyLevel(
+int sqlite3BtreeSetPagerFlags(
Btree *p, /* The btree to set the safety level on */
- int level, /* PRAGMA synchronous. 1=OFF, 2=NORMAL, 3=FULL */
- int fullSync, /* PRAGMA fullfsync. */
- int ckptFullSync /* PRAGMA checkpoint_fullfync */
+ unsigned pgFlags /* Various PAGER_* flags */
){
BtShared *pBt = p->pBt;
assert( sqlite3_mutex_held(p->db->mutex) );
- assert( level>=1 && level<=3 );
sqlite3BtreeEnter(p);
- sqlite3PagerSetSafetyLevel(pBt->pPager, level, fullSync, ckptFullSync);
+ sqlite3PagerSetFlags(pBt->pPager, pgFlags);
sqlite3BtreeLeave(p);
return SQLITE_OK;
}
@@ -2381,7 +2404,7 @@ static int lockBtree(BtShared *pBt){
assert( pBt->pPage1==0 );
rc = sqlite3PagerSharedLock(pBt->pPager);
if( rc!=SQLITE_OK ) return rc;
- rc = btreeGetPage(pBt, 1, &pPage1, 0, 0);
+ rc = btreeGetPage(pBt, 1, &pPage1, 0);
if( rc!=SQLITE_OK ) return rc;
/* Do some checking to help insure the file we opened really is
@@ -2534,7 +2557,8 @@ static int countValidCursors(BtShared *pBt, int wrOnly){
BtCursor *pCur;
int r = 0;
for(pCur=pBt->pCursor; pCur; pCur=pCur->pNext){
- if( (wrOnly==0 || pCur->wrFlag) && pCur->eState!=CURSOR_FAULT ) r++;
+ if( (wrOnly==0 || (pCur->curFlags & BTCF_WriteFlag)!=0)
+ && pCur->eState!=CURSOR_FAULT ) r++;
}
return r;
}
@@ -2668,7 +2692,7 @@ int sqlite3BtreeBeginTrans(Btree *p, int wrflag){
if( p->inTrans==TRANS_WRITE || (p->inTrans==TRANS_READ && !wrflag) ){
goto trans_begun;
}
- assert( IfNotOmitAV(pBt->bDoTruncate)==0 );
+ assert( pBt->inTransaction==TRANS_WRITE || IfNotOmitAV(pBt->bDoTruncate)==0 );
/* Write transactions are not possible on a read-only database */
if( (pBt->btsFlags & BTS_READ_ONLY)!=0 && wrflag ){
@@ -2963,7 +2987,7 @@ static int relocatePage(
** iPtrPage.
*/
if( eType!=PTRMAP_ROOTPAGE ){
- rc = btreeGetPage(pBt, iPtrPage, &pPtrPage, 0, 0);
+ rc = btreeGetPage(pBt, iPtrPage, &pPtrPage, 0);
if( rc!=SQLITE_OK ){
return rc;
}
@@ -3047,7 +3071,7 @@ static int incrVacuumStep(BtShared *pBt, Pgno nFin, Pgno iLastPg, int bCommit){
u8 eMode = BTALLOC_ANY; /* Mode parameter for allocateBtreePage() */
Pgno iNear = 0; /* nearby parameter for allocateBtreePage() */
- rc = btreeGetPage(pBt, iLastPg, &pLastPg, 0, 0);
+ rc = btreeGetPage(pBt, iLastPg, &pLastPg, 0);
if( rc!=SQLITE_OK ){
return rc;
}
@@ -3158,7 +3182,7 @@ int sqlite3BtreeIncrVacuum(Btree *p){
/*
** This routine is called prior to sqlite3PagerCommit when a transaction
-** is commited for an auto-vacuum database.
+** is committed for an auto-vacuum database.
**
** If SQLITE_OK is returned, then *pnTrunc is set to the number of pages
** the database file should be truncated to during the commit process.
@@ -3273,12 +3297,13 @@ int sqlite3BtreeCommitPhaseOne(Btree *p, const char *zMaster){
*/
static void btreeEndTransaction(Btree *p){
BtShared *pBt = p->pBt;
+ sqlite3 *db = p->db;
assert( sqlite3BtreeHoldsMutex(p) );
#ifndef SQLITE_OMIT_AUTOVACUUM
pBt->bDoTruncate = 0;
#endif
- if( p->inTrans>TRANS_NONE && p->db->activeVdbeCnt>1 ){
+ if( p->inTrans>TRANS_NONE && db->nVdbeRead>1 ){
/* If there are other active statements that belong to this database
** handle, downgrade to a read-only transaction. The other statements
** may still be reading from the database. */
@@ -3445,7 +3470,7 @@ int sqlite3BtreeRollback(Btree *p, int tripCode){
/* The rollback may have destroyed the pPage1->aData value. So
** call btreeGetPage() on page 1 again to make
** sure pPage1->aData is set correctly. */
- if( btreeGetPage(pBt, 1, &pPage1, 0, 0)==SQLITE_OK ){
+ if( btreeGetPage(pBt, 1, &pPage1, 0)==SQLITE_OK ){
int nPage = get4byte(28+(u8*)pPage1->aData);
testcase( nPage==0 );
if( nPage==0 ) sqlite3PagerPagecount(pBt->pPager, &nPage);
@@ -3608,14 +3633,14 @@ static int btreeCursor(
pCur->pKeyInfo = pKeyInfo;
pCur->pBtree = p;
pCur->pBt = pBt;
- pCur->wrFlag = (u8)wrFlag;
+ assert( wrFlag==0 || wrFlag==BTCF_WriteFlag );
+ pCur->curFlags = wrFlag;
pCur->pNext = pBt->pCursor;
if( pCur->pNext ){
pCur->pNext->pPrev = pCur;
}
pBt->pCursor = pCur;
pCur->eState = CURSOR_INVALID;
- pCur->cachedRowid = 0;
return SQLITE_OK;
}
int sqlite3BtreeCursor(
@@ -3657,36 +3682,6 @@ void sqlite3BtreeCursorZero(BtCursor *p){
}
/*
-** Set the cached rowid value of every cursor in the same database file
-** as pCur and having the same root page number as pCur. The value is
-** set to iRowid.
-**
-** Only positive rowid values are considered valid for this cache.
-** The cache is initialized to zero, indicating an invalid cache.
-** A btree will work fine with zero or negative rowids. We just cannot
-** cache zero or negative rowids, which means tables that use zero or
-** negative rowids might run a little slower. But in practice, zero
-** or negative rowids are very uncommon so this should not be a problem.
-*/
-void sqlite3BtreeSetCachedRowid(BtCursor *pCur, sqlite3_int64 iRowid){
- BtCursor *p;
- for(p=pCur->pBt->pCursor; p; p=p->pNext){
- if( p->pgnoRoot==pCur->pgnoRoot ) p->cachedRowid = iRowid;
- }
- assert( pCur->cachedRowid==iRowid );
-}
-
-/*
-** Return the cached rowid for the given cursor. A negative or zero
-** return value indicates that the rowid cache is invalid and should be
-** ignored. If the rowid cache has never before been set, then a
-** zero is returned.
-*/
-sqlite3_int64 sqlite3BtreeGetCachedRowid(BtCursor *pCur){
- return pCur->cachedRowid;
-}
-
-/*
** Close a cursor. The read lock on the database file is released
** when the last cursor is closed.
*/
@@ -3709,7 +3704,7 @@ int sqlite3BtreeCloseCursor(BtCursor *pCur){
releasePage(pCur->apPage[i]);
}
unlockBtreeIfUnused(pBt);
- invalidateOverflowCache(pCur);
+ sqlite3DbFree(pBtree->db, pCur->aOverflow);
/* sqlite3_free(pCur); */
sqlite3BtreeLeave(pBtree);
}
@@ -3737,7 +3732,7 @@ int sqlite3BtreeCloseCursor(BtCursor *pCur){
int iPage = pCur->iPage;
memset(&info, 0, sizeof(info));
btreeParseCell(pCur->apPage[iPage], pCur->aiIdx[iPage], &info);
- assert( memcmp(&info, &pCur->info, sizeof(info))==0 );
+ assert( CORRUPT_DB || memcmp(&info, &pCur->info, sizeof(info))==0 );
}
#else
#define assertCellInfo(x)
@@ -3748,7 +3743,7 @@ int sqlite3BtreeCloseCursor(BtCursor *pCur){
if( pCur->info.nSize==0 ){
int iPage = pCur->iPage;
btreeParseCell(pCur->apPage[iPage],pCur->aiIdx[iPage],&pCur->info);
- pCur->validNKey = 1;
+ pCur->curFlags |= BTCF_ValidNKey;
}else{
assertCellInfo(pCur);
}
@@ -3758,8 +3753,8 @@ int sqlite3BtreeCloseCursor(BtCursor *pCur){
#define getCellInfo(pCur) \
if( pCur->info.nSize==0 ){ \
int iPage = pCur->iPage; \
- btreeParseCell(pCur->apPage[iPage],pCur->aiIdx[iPage],&pCur->info); \
- pCur->validNKey = 1; \
+ btreeParseCell(pCur->apPage[iPage],pCur->aiIdx[iPage],&pCur->info); \
+ pCur->curFlags |= BTCF_ValidNKey; \
}else{ \
assertCellInfo(pCur); \
}
@@ -3880,7 +3875,7 @@ static int getOverflowPage(
assert( next==0 || rc==SQLITE_DONE );
if( rc==SQLITE_OK ){
- rc = btreeGetPage(pBt, ovfl, &pPage, 0, (ppPage==0));
+ rc = btreeGetPage(pBt, ovfl, &pPage, (ppPage==0) ? PAGER_GET_READONLY : 0);
assert( rc==SQLITE_OK || pPage==0 );
if( rc==SQLITE_OK ){
next = get4byte(pPage->aData);
@@ -3930,10 +3925,12 @@ static int copyPayload(
/*
** This function is used to read or overwrite payload information
-** for the entry that the pCur cursor is pointing to. If the eOp
-** parameter is 0, this is a read operation (data copied into
-** buffer pBuf). If it is non-zero, a write (data copied from
-** buffer pBuf).
+** for the entry that the pCur cursor is pointing to. The eOp
+** argument is interpreted as follows:
+**
+** 0: The operation is a read. Populate the overflow cache.
+** 1: The operation is a write. Populate the overflow cache.
+** 2: The operation is a read. Do not populate the overflow cache.
**
** A total of "amt" bytes are read or written beginning at "offset".
** Data is read to or from the buffer pBuf.
@@ -3941,11 +3938,11 @@ static int copyPayload(
** The content being read or written might appear on the main page
** or be scattered out on multiple overflow pages.
**
-** If the BtCursor.isIncrblobHandle flag is set, and the current
-** cursor entry uses one or more overflow pages, this function
-** allocates space for and lazily popluates the overflow page-list
-** cache array (BtCursor.aOverflow). Subsequent calls use this
-** cache to make seeking to the supplied offset more efficient.
+** If the current cursor entry uses one or more overflow pages and the
+** eOp argument is not 2, this function may allocate space for and lazily
+** popluates the overflow page-list cache array (BtCursor.aOverflow).
+** Subsequent calls use this cache to make seeking to the supplied offset
+** more efficient.
**
** Once an overflow page-list cache has been allocated, it may be
** invalidated if some other cursor writes to the same table, or if
@@ -3969,15 +3966,22 @@ static int accessPayload(
int iIdx = 0;
MemPage *pPage = pCur->apPage[pCur->iPage]; /* Btree page of current entry */
BtShared *pBt = pCur->pBt; /* Btree this cursor belongs to */
+#ifdef SQLITE_DIRECT_OVERFLOW_READ
+ int bEnd; /* True if reading to end of data */
+#endif
assert( pPage );
assert( pCur->eState==CURSOR_VALID );
assert( pCur->aiIdx[pCur->iPage]<pPage->nCell );
assert( cursorHoldsMutex(pCur) );
+ assert( eOp!=2 || offset==0 ); /* Always start from beginning for eOp==2 */
getCellInfo(pCur);
aPayload = pCur->info.pCell + pCur->info.nHeader;
nKey = (pPage->intKey ? 0 : (int)pCur->info.nKey);
+#ifdef SQLITE_DIRECT_OVERFLOW_READ
+ bEnd = (offset+amt==nKey+pCur->info.nData);
+#endif
if( NEVER(offset+amt > nKey+pCur->info.nData)
|| &aPayload[pCur->info.nLocal] > &pPage->aData[pBt->usableSize]
@@ -3992,7 +3996,7 @@ static int accessPayload(
if( a+offset>pCur->info.nLocal ){
a = pCur->info.nLocal - offset;
}
- rc = copyPayload(&aPayload[offset], pBuf, a, eOp, pPage->pDbPage);
+ rc = copyPayload(&aPayload[offset], pBuf, a, (eOp & 0x01), pPage->pDbPage);
offset = 0;
pBuf += a;
amt -= a;
@@ -4006,21 +4010,30 @@ static int accessPayload(
nextPage = get4byte(&aPayload[pCur->info.nLocal]);
-#ifndef SQLITE_OMIT_INCRBLOB
- /* If the isIncrblobHandle flag is set and the BtCursor.aOverflow[]
- ** has not been allocated, allocate it now. The array is sized at
- ** one entry for each overflow page in the overflow chain. The
- ** page number of the first overflow page is stored in aOverflow[0],
- ** etc. A value of 0 in the aOverflow[] array means "not yet known"
- ** (the cache is lazily populated).
+ /* If the BtCursor.aOverflow[] has not been allocated, allocate it now.
+ ** Except, do not allocate aOverflow[] for eOp==2.
+ **
+ ** The aOverflow[] array is sized at one entry for each overflow page
+ ** in the overflow chain. The page number of the first overflow page is
+ ** stored in aOverflow[0], etc. A value of 0 in the aOverflow[] array
+ ** means "not yet known" (the cache is lazily populated).
*/
- if( pCur->isIncrblobHandle && !pCur->aOverflow ){
+ if( eOp!=2 && (pCur->curFlags & BTCF_ValidOvfl)==0 ){
int nOvfl = (pCur->info.nPayload-pCur->info.nLocal+ovflSize-1)/ovflSize;
- pCur->aOverflow = (Pgno *)sqlite3MallocZero(sizeof(Pgno)*nOvfl);
- /* nOvfl is always positive. If it were zero, fetchPayload would have
- ** been used instead of this routine. */
- if( ALWAYS(nOvfl) && !pCur->aOverflow ){
- rc = SQLITE_NOMEM;
+ if( nOvfl>pCur->nOvflAlloc ){
+ Pgno *aNew = (Pgno*)sqlite3DbRealloc(
+ pCur->pBtree->db, pCur->aOverflow, nOvfl*2*sizeof(Pgno)
+ );
+ if( aNew==0 ){
+ rc = SQLITE_NOMEM;
+ }else{
+ pCur->nOvflAlloc = nOvfl*2;
+ pCur->aOverflow = aNew;
+ }
+ }
+ if( rc==SQLITE_OK ){
+ memset(pCur->aOverflow, 0, nOvfl*sizeof(Pgno));
+ pCur->curFlags |= BTCF_ValidOvfl;
}
}
@@ -4028,22 +4041,19 @@ static int accessPayload(
** entry for the first required overflow page is valid, skip
** directly to it.
*/
- if( pCur->aOverflow && pCur->aOverflow[offset/ovflSize] ){
+ if( (pCur->curFlags & BTCF_ValidOvfl)!=0 && pCur->aOverflow[offset/ovflSize] ){
iIdx = (offset/ovflSize);
nextPage = pCur->aOverflow[iIdx];
offset = (offset%ovflSize);
}
-#endif
for( ; rc==SQLITE_OK && amt>0 && nextPage; iIdx++){
-#ifndef SQLITE_OMIT_INCRBLOB
/* If required, populate the overflow page-list cache. */
- if( pCur->aOverflow ){
+ if( (pCur->curFlags & BTCF_ValidOvfl)!=0 ){
assert(!pCur->aOverflow[iIdx] || pCur->aOverflow[iIdx]==nextPage);
pCur->aOverflow[iIdx] = nextPage;
}
-#endif
if( offset>=ovflSize ){
/* The only reason to read this page is to obtain the page
@@ -4051,13 +4061,17 @@ static int accessPayload(
** data is not required. So first try to lookup the overflow
** page-list cache, if any, then fall back to the getOverflowPage()
** function.
+ **
+ ** Note that the aOverflow[] array must be allocated because eOp!=2
+ ** here. If eOp==2, then offset==0 and this branch is never taken.
*/
-#ifndef SQLITE_OMIT_INCRBLOB
- if( pCur->aOverflow && pCur->aOverflow[iIdx+1] ){
+ assert( eOp!=2 );
+ assert( pCur->curFlags & BTCF_ValidOvfl );
+ if( pCur->aOverflow[iIdx+1] ){
nextPage = pCur->aOverflow[iIdx+1];
- } else
-#endif
+ }else{
rc = getOverflowPage(pBt, nextPage, 0, &nextPage);
+ }
offset -= ovflSize;
}else{
/* Need to read this page properly. It contains some of the
@@ -4079,13 +4093,15 @@ static int accessPayload(
** 3) the database is file-backed, and
** 4) there is no open write-transaction, and
** 5) the database is not a WAL database,
+ ** 6) all data from the page is being read.
**
** then data can be read directly from the database file into the
** output buffer, bypassing the page-cache altogether. This speeds
** up loading large records that span many overflow pages.
*/
- if( eOp==0 /* (1) */
+ if( (eOp&0x01)==0 /* (1) */
&& offset==0 /* (2) */
+ && (bEnd || a==ovflSize) /* (6) */
&& pBt->inTransaction==TRANS_READ /* (4) */
&& (fd = sqlite3PagerFile(pBt->pPager))->pMethods /* (3) */
&& pBt->pPage1->aData[19]==0x01 /* (5) */
@@ -4102,12 +4118,12 @@ static int accessPayload(
{
DbPage *pDbPage;
rc = sqlite3PagerAcquire(pBt->pPager, nextPage, &pDbPage,
- (eOp==0 ? PAGER_ACQUIRE_READONLY : 0)
+ ((eOp&0x01)==0 ? PAGER_GET_READONLY : 0)
);
if( rc==SQLITE_OK ){
aPayload = sqlite3PagerGetData(pDbPage);
nextPage = get4byte(aPayload);
- rc = copyPayload(&aPayload[offset+4], pBuf, a, eOp, pDbPage);
+ rc = copyPayload(&aPayload[offset+4], pBuf, a, (eOp&0x01), pDbPage);
sqlite3PagerUnref(pDbPage);
offset = 0;
}
@@ -4176,10 +4192,10 @@ int sqlite3BtreeData(BtCursor *pCur, u32 offset, u32 amt, void *pBuf){
/*
** Return a pointer to payload information from the entry that the
** pCur cursor is pointing to. The pointer is to the beginning of
-** the key if skipKey==0 and it points to the beginning of data if
-** skipKey==1. The number of bytes of available key/data is written
-** into *pAmt. If *pAmt==0, then the value returned will not be
-** a valid pointer.
+** the key if index btrees (pPage->intKey==0) and is the data for
+** table btrees (pPage->intKey==1). The number of bytes of available
+** key/data is written into *pAmt. If *pAmt==0, then the value
+** returned will not be a valid pointer.
**
** This routine is an optimization. It is common for the entire key
** and data to fit on the local page and for there to be no overflow
@@ -4192,41 +4208,18 @@ int sqlite3BtreeData(BtCursor *pCur, u32 offset, u32 amt, void *pBuf){
** page of the database. The data might change or move the next time
** any btree routine is called.
*/
-static const unsigned char *fetchPayload(
+static const void *fetchPayload(
BtCursor *pCur, /* Cursor pointing to entry to read from */
- int *pAmt, /* Write the number of available bytes here */
- int skipKey /* read beginning at data if this is true */
+ u32 *pAmt /* Write the number of available bytes here */
){
- unsigned char *aPayload;
- MemPage *pPage;
- u32 nKey;
- u32 nLocal;
-
assert( pCur!=0 && pCur->iPage>=0 && pCur->apPage[pCur->iPage]);
assert( pCur->eState==CURSOR_VALID );
+ assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
assert( cursorHoldsMutex(pCur) );
- pPage = pCur->apPage[pCur->iPage];
- assert( pCur->aiIdx[pCur->iPage]<pPage->nCell );
- if( NEVER(pCur->info.nSize==0) ){
- btreeParseCell(pCur->apPage[pCur->iPage], pCur->aiIdx[pCur->iPage],
- &pCur->info);
- }
- aPayload = pCur->info.pCell;
- aPayload += pCur->info.nHeader;
- if( pPage->intKey ){
- nKey = 0;
- }else{
- nKey = (int)pCur->info.nKey;
- }
- if( skipKey ){
- aPayload += nKey;
- nLocal = pCur->info.nLocal - nKey;
- }else{
- nLocal = pCur->info.nLocal;
- assert( nLocal<=nKey );
- }
- *pAmt = nLocal;
- return aPayload;
+ assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
+ assert( pCur->info.nSize>0 );
+ *pAmt = pCur->info.nLocal;
+ return (void*)(pCur->info.pCell + pCur->info.nHeader);
}
@@ -4244,23 +4237,11 @@ static const unsigned char *fetchPayload(
** These routines is used to get quick access to key and data
** in the common case where no overflow pages are used.
*/
-const void *sqlite3BtreeKeyFetch(BtCursor *pCur, int *pAmt){
- const void *p = 0;
- assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
- assert( cursorHoldsMutex(pCur) );
- if( ALWAYS(pCur->eState==CURSOR_VALID) ){
- p = (const void*)fetchPayload(pCur, pAmt, 0);
- }
- return p;
+const void *sqlite3BtreeKeyFetch(BtCursor *pCur, u32 *pAmt){
+ return fetchPayload(pCur, pAmt);
}
-const void *sqlite3BtreeDataFetch(BtCursor *pCur, int *pAmt){
- const void *p = 0;
- assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
- assert( cursorHoldsMutex(pCur) );
- if( ALWAYS(pCur->eState==CURSOR_VALID) ){
- p = (const void*)fetchPayload(pCur, pAmt, 1);
- }
- return p;
+const void *sqlite3BtreeDataFetch(BtCursor *pCur, u32 *pAmt){
+ return fetchPayload(pCur, pAmt);
}
@@ -4286,14 +4267,15 @@ static int moveToChild(BtCursor *pCur, u32 newPgno){
if( pCur->iPage>=(BTCURSOR_MAX_DEPTH-1) ){
return SQLITE_CORRUPT_BKPT;
}
- rc = getAndInitPage(pBt, newPgno, &pNewPage, (pCur->wrFlag==0));
+ rc = getAndInitPage(pBt, newPgno, &pNewPage,
+ (pCur->curFlags & BTCF_WriteFlag)==0 ? PAGER_GET_READONLY : 0);
if( rc ) return rc;
pCur->apPage[i+1] = pNewPage;
pCur->aiIdx[i+1] = 0;
pCur->iPage++;
pCur->info.nSize = 0;
- pCur->validNKey = 0;
+ pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
if( pNewPage->nCell<1 || pNewPage->intKey!=pCur->apPage[i]->intKey ){
return SQLITE_CORRUPT_BKPT;
}
@@ -4351,7 +4333,7 @@ static void moveToParent(BtCursor *pCur){
releasePage(pCur->apPage[pCur->iPage]);
pCur->iPage--;
pCur->info.nSize = 0;
- pCur->validNKey = 0;
+ pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
}
/*
@@ -4378,8 +4360,6 @@ static void moveToParent(BtCursor *pCur){
static int moveToRoot(BtCursor *pCur){
MemPage *pRoot;
int rc = SQLITE_OK;
- Btree *p = pCur->pBtree;
- BtShared *pBt = p->pBt;
assert( cursorHoldsMutex(pCur) );
assert( CURSOR_INVALID < CURSOR_REQUIRESEEK );
@@ -4394,55 +4374,51 @@ static int moveToRoot(BtCursor *pCur){
}
if( pCur->iPage>=0 ){
- int i;
- for(i=1; i<=pCur->iPage; i++){
- releasePage(pCur->apPage[i]);
- }
- pCur->iPage = 0;
+ while( pCur->iPage ) releasePage(pCur->apPage[pCur->iPage--]);
}else if( pCur->pgnoRoot==0 ){
pCur->eState = CURSOR_INVALID;
return SQLITE_OK;
}else{
- rc = getAndInitPage(pBt, pCur->pgnoRoot, &pCur->apPage[0], pCur->wrFlag==0);
+ rc = getAndInitPage(pCur->pBtree->pBt, pCur->pgnoRoot, &pCur->apPage[0],
+ (pCur->curFlags & BTCF_WriteFlag)==0 ? PAGER_GET_READONLY : 0);
if( rc!=SQLITE_OK ){
pCur->eState = CURSOR_INVALID;
return rc;
}
pCur->iPage = 0;
-
- /* If pCur->pKeyInfo is not NULL, then the caller that opened this cursor
- ** expected to open it on an index b-tree. Otherwise, if pKeyInfo is
- ** NULL, the caller expects a table b-tree. If this is not the case,
- ** return an SQLITE_CORRUPT error. */
- assert( pCur->apPage[0]->intKey==1 || pCur->apPage[0]->intKey==0 );
- if( (pCur->pKeyInfo==0)!=pCur->apPage[0]->intKey ){
- return SQLITE_CORRUPT_BKPT;
- }
}
-
- /* Assert that the root page is of the correct type. This must be the
- ** case as the call to this function that loaded the root-page (either
- ** this call or a previous invocation) would have detected corruption
- ** if the assumption were not true, and it is not possible for the flags
- ** byte to have been modified while this cursor is holding a reference
- ** to the page. */
pRoot = pCur->apPage[0];
assert( pRoot->pgno==pCur->pgnoRoot );
- assert( pRoot->isInit && (pCur->pKeyInfo==0)==pRoot->intKey );
+
+ /* If pCur->pKeyInfo is not NULL, then the caller that opened this cursor
+ ** expected to open it on an index b-tree. Otherwise, if pKeyInfo is
+ ** NULL, the caller expects a table b-tree. If this is not the case,
+ ** return an SQLITE_CORRUPT error.
+ **
+ ** Earlier versions of SQLite assumed that this test could not fail
+ ** if the root page was already loaded when this function was called (i.e.
+ ** if pCur->iPage>=0). But this is not so if the database is corrupted
+ ** in such a way that page pRoot is linked into a second b-tree table
+ ** (or the freelist). */
+ assert( pRoot->intKey==1 || pRoot->intKey==0 );
+ if( pRoot->isInit==0 || (pCur->pKeyInfo==0)!=pRoot->intKey ){
+ return SQLITE_CORRUPT_BKPT;
+ }
pCur->aiIdx[0] = 0;
pCur->info.nSize = 0;
- pCur->atLast = 0;
- pCur->validNKey = 0;
+ pCur->curFlags &= ~(BTCF_AtLast|BTCF_ValidNKey|BTCF_ValidOvfl);
- if( pRoot->nCell==0 && !pRoot->leaf ){
+ if( pRoot->nCell>0 ){
+ pCur->eState = CURSOR_VALID;
+ }else if( !pRoot->leaf ){
Pgno subpage;
if( pRoot->pgno!=1 ) return SQLITE_CORRUPT_BKPT;
subpage = get4byte(&pRoot->aData[pRoot->hdrOffset+8]);
pCur->eState = CURSOR_VALID;
rc = moveToChild(pCur, subpage);
}else{
- pCur->eState = ((pRoot->nCell>0)?CURSOR_VALID:CURSOR_INVALID);
+ pCur->eState = CURSOR_INVALID;
}
return rc;
}
@@ -4494,7 +4470,7 @@ static int moveToRightmost(BtCursor *pCur){
if( rc==SQLITE_OK ){
pCur->aiIdx[pCur->iPage] = pPage->nCell-1;
pCur->info.nSize = 0;
- pCur->validNKey = 0;
+ pCur->curFlags &= ~BTCF_ValidNKey;
}
return rc;
}
@@ -4533,7 +4509,7 @@ int sqlite3BtreeLast(BtCursor *pCur, int *pRes){
assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
/* If the cursor already points to the last entry, this is a no-op. */
- if( CURSOR_VALID==pCur->eState && pCur->atLast ){
+ if( CURSOR_VALID==pCur->eState && (pCur->curFlags & BTCF_AtLast)!=0 ){
#ifdef SQLITE_DEBUG
/* This block serves to assert() that the cursor really does point
** to the last entry in the b-tree. */
@@ -4556,7 +4532,12 @@ int sqlite3BtreeLast(BtCursor *pCur, int *pRes){
assert( pCur->eState==CURSOR_VALID );
*pRes = 0;
rc = moveToRightmost(pCur);
- pCur->atLast = rc==SQLITE_OK ?1:0;
+ if( rc==SQLITE_OK ){
+ pCur->curFlags |= BTCF_AtLast;
+ }else{
+ pCur->curFlags &= ~BTCF_AtLast;
+ }
+
}
}
return rc;
@@ -4598,6 +4579,7 @@ int sqlite3BtreeMovetoUnpacked(
int *pRes /* Write search results here */
){
int rc;
+ RecordCompare xRecordCompare;
assert( cursorHoldsMutex(pCur) );
assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
@@ -4606,19 +4588,30 @@ int sqlite3BtreeMovetoUnpacked(
/* If the cursor is already positioned at the point we are trying
** to move to, then just return without doing any work */
- if( pCur->eState==CURSOR_VALID && pCur->validNKey
+ if( pCur->eState==CURSOR_VALID && (pCur->curFlags & BTCF_ValidNKey)!=0
&& pCur->apPage[0]->intKey
){
if( pCur->info.nKey==intKey ){
*pRes = 0;
return SQLITE_OK;
}
- if( pCur->atLast && pCur->info.nKey<intKey ){
+ if( (pCur->curFlags & BTCF_AtLast)!=0 && pCur->info.nKey<intKey ){
*pRes = -1;
return SQLITE_OK;
}
}
+ if( pIdxKey ){
+ xRecordCompare = sqlite3VdbeFindCompare(pIdxKey);
+ pIdxKey->isCorrupt = 0;
+ assert( pIdxKey->default_rc==1
+ || pIdxKey->default_rc==0
+ || pIdxKey->default_rc==-1
+ );
+ }else{
+ xRecordCompare = 0; /* All keys are integers */
+ }
+
rc = moveToRoot(pCur);
if( rc ){
return rc;
@@ -4633,10 +4626,10 @@ int sqlite3BtreeMovetoUnpacked(
}
assert( pCur->apPage[0]->intKey || pIdxKey );
for(;;){
- int lwr, upr, idx;
+ int lwr, upr, idx, c;
Pgno chldPg;
MemPage *pPage = pCur->apPage[pCur->iPage];
- int c;
+ u8 *pCell; /* Pointer to current cell in pPage */
/* pPage->nCell must be greater than zero. If this is the root-page
** the cursor would have been INVALID above and this for(;;) loop
@@ -4648,35 +4641,47 @@ int sqlite3BtreeMovetoUnpacked(
assert( pPage->intKey==(pIdxKey==0) );
lwr = 0;
upr = pPage->nCell-1;
- if( biasRight ){
- pCur->aiIdx[pCur->iPage] = (u16)(idx = upr);
- }else{
- pCur->aiIdx[pCur->iPage] = (u16)(idx = (upr+lwr)/2);
- }
- for(;;){
- u8 *pCell; /* Pointer to current cell in pPage */
-
- assert( idx==pCur->aiIdx[pCur->iPage] );
- pCur->info.nSize = 0;
- pCell = findCell(pPage, idx) + pPage->childPtrSize;
- if( pPage->intKey ){
+ assert( biasRight==0 || biasRight==1 );
+ idx = upr>>(1-biasRight); /* idx = biasRight ? upr : (lwr+upr)/2; */
+ pCur->aiIdx[pCur->iPage] = (u16)idx;
+ if( xRecordCompare==0 ){
+ for(;;){
i64 nCellKey;
+ pCell = findCell(pPage, idx) + pPage->childPtrSize;
if( pPage->hasData ){
- u32 dummy;
- pCell += getVarint32(pCell, dummy);
+ while( 0x80 <= *(pCell++) ){
+ if( pCell>=pPage->aDataEnd ) return SQLITE_CORRUPT_BKPT;
+ }
}
getVarint(pCell, (u64*)&nCellKey);
- if( nCellKey==intKey ){
- c = 0;
- }else if( nCellKey<intKey ){
- c = -1;
+ if( nCellKey<intKey ){
+ lwr = idx+1;
+ if( lwr>upr ){ c = -1; break; }
+ }else if( nCellKey>intKey ){
+ upr = idx-1;
+ if( lwr>upr ){ c = +1; break; }
}else{
- assert( nCellKey>intKey );
- c = +1;
+ assert( nCellKey==intKey );
+ pCur->curFlags |= BTCF_ValidNKey;
+ pCur->info.nKey = nCellKey;
+ pCur->aiIdx[pCur->iPage] = (u16)idx;
+ if( !pPage->leaf ){
+ lwr = idx;
+ goto moveto_next_layer;
+ }else{
+ *pRes = 0;
+ rc = SQLITE_OK;
+ goto moveto_finish;
+ }
}
- pCur->validNKey = 1;
- pCur->info.nKey = nCellKey;
- }else{
+ assert( lwr+upr>=0 );
+ idx = (lwr+upr)>>1; /* idx = (lwr+upr)/2; */
+ }
+ }else{
+ for(;;){
+ int nCell;
+ pCell = findCell(pPage, idx) + pPage->childPtrSize;
+
/* The maximum supported page-size is 65536 bytes. This means that
** the maximum number of record bytes stored on an index B-Tree
** page is less than 16384 bytes and may be stored as a 2-byte
@@ -4685,23 +4690,20 @@ int sqlite3BtreeMovetoUnpacked(
** stored entirely within the b-tree page by inspecting the first
** 2 bytes of the cell.
*/
- int nCell = pCell[0];
- if( nCell<=pPage->max1bytePayload
- /* && (pCell+nCell)<pPage->aDataEnd */
- ){
+ nCell = pCell[0];
+ if( nCell<=pPage->max1bytePayload ){
/* This branch runs if the record-size field of the cell is a
** single byte varint and the record fits entirely on the main
** b-tree page. */
testcase( pCell+nCell+1==pPage->aDataEnd );
- c = sqlite3VdbeRecordCompare(nCell, (void*)&pCell[1], pIdxKey);
+ c = xRecordCompare(nCell, (void*)&pCell[1], pIdxKey, 0);
}else if( !(pCell[1] & 0x80)
&& (nCell = ((nCell&0x7f)<<7) + pCell[1])<=pPage->maxLocal
- /* && (pCell+nCell+2)<=pPage->aDataEnd */
){
/* The record-size field is a 2 byte varint and the record
** fits entirely on the main b-tree page. */
testcase( pCell+nCell+2==pPage->aDataEnd );
- c = sqlite3VdbeRecordCompare(nCell, (void*)&pCell[2], pIdxKey);
+ c = xRecordCompare(nCell, (void*)&pCell[2], pIdxKey, 0);
}else{
/* The record flows over onto one or more overflow pages. In
** this case the whole cell needs to be parsed, a buffer allocated
@@ -4716,57 +4718,55 @@ int sqlite3BtreeMovetoUnpacked(
rc = SQLITE_NOMEM;
goto moveto_finish;
}
- rc = accessPayload(pCur, 0, nCell, (unsigned char*)pCellKey, 0);
+ pCur->aiIdx[pCur->iPage] = (u16)idx;
+ rc = accessPayload(pCur, 0, nCell, (unsigned char*)pCellKey, 2);
if( rc ){
sqlite3_free(pCellKey);
goto moveto_finish;
}
- c = sqlite3VdbeRecordCompare(nCell, pCellKey, pIdxKey);
+ c = xRecordCompare(nCell, pCellKey, pIdxKey, 0);
sqlite3_free(pCellKey);
}
- }
- if( c==0 ){
- if( pPage->intKey && !pPage->leaf ){
- lwr = idx;
- break;
+ assert( pIdxKey->isCorrupt==0 || c==0 );
+ if( c<0 ){
+ lwr = idx+1;
+ }else if( c>0 ){
+ upr = idx-1;
}else{
+ assert( c==0 );
*pRes = 0;
rc = SQLITE_OK;
+ pCur->aiIdx[pCur->iPage] = (u16)idx;
+ if( pIdxKey->isCorrupt ) rc = SQLITE_CORRUPT;
goto moveto_finish;
}
+ if( lwr>upr ) break;
+ assert( lwr+upr>=0 );
+ idx = (lwr+upr)>>1; /* idx = (lwr+upr)/2 */
}
- if( c<0 ){
- lwr = idx+1;
- }else{
- upr = idx-1;
- }
- if( lwr>upr ){
- break;
- }
- pCur->aiIdx[pCur->iPage] = (u16)(idx = (lwr+upr)/2);
}
assert( lwr==upr+1 || (pPage->intKey && !pPage->leaf) );
assert( pPage->isInit );
if( pPage->leaf ){
- chldPg = 0;
- }else if( lwr>=pPage->nCell ){
- chldPg = get4byte(&pPage->aData[pPage->hdrOffset+8]);
- }else{
- chldPg = get4byte(findCell(pPage, lwr));
- }
- if( chldPg==0 ){
assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
+ pCur->aiIdx[pCur->iPage] = (u16)idx;
*pRes = c;
rc = SQLITE_OK;
goto moveto_finish;
}
+moveto_next_layer:
+ if( lwr>=pPage->nCell ){
+ chldPg = get4byte(&pPage->aData[pPage->hdrOffset+8]);
+ }else{
+ chldPg = get4byte(findCell(pPage, lwr));
+ }
pCur->aiIdx[pCur->iPage] = (u16)lwr;
- pCur->info.nSize = 0;
- pCur->validNKey = 0;
rc = moveToChild(pCur, chldPg);
- if( rc ) goto moveto_finish;
+ if( rc ) break;
}
moveto_finish:
+ pCur->info.nSize = 0;
+ pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
return rc;
}
@@ -4791,6 +4791,15 @@ int sqlite3BtreeEof(BtCursor *pCur){
** successful then set *pRes=0. If the cursor
** was already pointing to the last entry in the database before
** this routine was called, then set *pRes=1.
+**
+** The calling function will set *pRes to 0 or 1. The initial *pRes value
+** will be 1 if the cursor being stepped corresponds to an SQL index and
+** if this routine could have been skipped if that SQL index had been
+** a unique index. Otherwise the caller will have set *pRes to zero.
+** Zero is the common case. The btree implementation is free to use the
+** initial *pRes value as a hint to improve performance, but the current
+** SQLite btree implementation does not. (Note that the comdb2 btree
+** implementation does use this hint, however.)
*/
int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
int rc;
@@ -4798,21 +4807,31 @@ int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
MemPage *pPage;
assert( cursorHoldsMutex(pCur) );
- rc = restoreCursorPosition(pCur);
- if( rc!=SQLITE_OK ){
- return rc;
- }
assert( pRes!=0 );
- if( CURSOR_INVALID==pCur->eState ){
- *pRes = 1;
- return SQLITE_OK;
- }
- if( pCur->skipNext>0 ){
- pCur->skipNext = 0;
- *pRes = 0;
- return SQLITE_OK;
+ assert( *pRes==0 || *pRes==1 );
+ assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
+ if( pCur->eState!=CURSOR_VALID ){
+ invalidateOverflowCache(pCur);
+ rc = restoreCursorPosition(pCur);
+ if( rc!=SQLITE_OK ){
+ *pRes = 0;
+ return rc;
+ }
+ if( CURSOR_INVALID==pCur->eState ){
+ *pRes = 1;
+ return SQLITE_OK;
+ }
+ if( pCur->skipNext ){
+ assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_SKIPNEXT );
+ pCur->eState = CURSOR_VALID;
+ if( pCur->skipNext>0 ){
+ pCur->skipNext = 0;
+ *pRes = 0;
+ return SQLITE_OK;
+ }
+ pCur->skipNext = 0;
+ }
}
- pCur->skipNext = 0;
pPage = pCur->apPage[pCur->iPage];
idx = ++pCur->aiIdx[pCur->iPage];
@@ -4826,11 +4845,14 @@ int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
testcase( idx>pPage->nCell );
pCur->info.nSize = 0;
- pCur->validNKey = 0;
+ pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
if( idx>=pPage->nCell ){
if( !pPage->leaf ){
rc = moveToChild(pCur, get4byte(&pPage->aData[pPage->hdrOffset+8]));
- if( rc ) return rc;
+ if( rc ){
+ *pRes = 0;
+ return rc;
+ }
rc = moveToLeftmost(pCur);
*pRes = 0;
return rc;
@@ -4866,27 +4888,48 @@ int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
** successful then set *pRes=0. If the cursor
** was already pointing to the first entry in the database before
** this routine was called, then set *pRes=1.
+**
+** The calling function will set *pRes to 0 or 1. The initial *pRes value
+** will be 1 if the cursor being stepped corresponds to an SQL index and
+** if this routine could have been skipped if that SQL index had been
+** a unique index. Otherwise the caller will have set *pRes to zero.
+** Zero is the common case. The btree implementation is free to use the
+** initial *pRes value as a hint to improve performance, but the current
+** SQLite btree implementation does not. (Note that the comdb2 btree
+** implementation does use this hint, however.)
*/
int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
int rc;
MemPage *pPage;
assert( cursorHoldsMutex(pCur) );
- rc = restoreCursorPosition(pCur);
- if( rc!=SQLITE_OK ){
- return rc;
- }
- pCur->atLast = 0;
- if( CURSOR_INVALID==pCur->eState ){
- *pRes = 1;
- return SQLITE_OK;
- }
- if( pCur->skipNext<0 ){
- pCur->skipNext = 0;
- *pRes = 0;
- return SQLITE_OK;
+ assert( pRes!=0 );
+ assert( *pRes==0 || *pRes==1 );
+ assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
+ pCur->curFlags &= ~(BTCF_AtLast|BTCF_ValidOvfl);
+ if( pCur->eState!=CURSOR_VALID ){
+ if( ALWAYS(pCur->eState>=CURSOR_REQUIRESEEK) ){
+ rc = btreeRestoreCursorPosition(pCur);
+ if( rc!=SQLITE_OK ){
+ *pRes = 0;
+ return rc;
+ }
+ }
+ if( CURSOR_INVALID==pCur->eState ){
+ *pRes = 1;
+ return SQLITE_OK;
+ }
+ if( pCur->skipNext ){
+ assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_SKIPNEXT );
+ pCur->eState = CURSOR_VALID;
+ if( pCur->skipNext<0 ){
+ pCur->skipNext = 0;
+ *pRes = 0;
+ return SQLITE_OK;
+ }
+ pCur->skipNext = 0;
+ }
}
- pCur->skipNext = 0;
pPage = pCur->apPage[pCur->iPage];
assert( pPage->isInit );
@@ -4894,6 +4937,7 @@ int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
int idx = pCur->aiIdx[pCur->iPage];
rc = moveToChild(pCur, get4byte(findCell(pPage, idx)));
if( rc ){
+ *pRes = 0;
return rc;
}
rc = moveToRightmost(pCur);
@@ -4907,7 +4951,7 @@ int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
moveToParent(pCur);
}
pCur->info.nSize = 0;
- pCur->validNKey = 0;
+ pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
pCur->aiIdx[pCur->iPage]--;
pPage = pCur->apPage[pCur->iPage];
@@ -5017,7 +5061,7 @@ static int allocateBtreePage(
if( iTrunk>mxPage ){
rc = SQLITE_CORRUPT_BKPT;
}else{
- rc = btreeGetPage(pBt, iTrunk, &pTrunk, 0, 0);
+ rc = btreeGetPage(pBt, iTrunk, &pTrunk, 0);
}
if( rc ){
pTrunk = 0;
@@ -5081,7 +5125,7 @@ static int allocateBtreePage(
goto end_allocate_page;
}
testcase( iNewTrunk==mxPage );
- rc = btreeGetPage(pBt, iNewTrunk, &pNewTrunk, 0, 0);
+ rc = btreeGetPage(pBt, iNewTrunk, &pNewTrunk, 0);
if( rc!=SQLITE_OK ){
goto end_allocate_page;
}
@@ -5160,8 +5204,8 @@ static int allocateBtreePage(
memcpy(&aData[8+closest*4], &aData[4+k*4], 4);
}
put4byte(&aData[4], k-1);
- noContent = !btreeGetHasContent(pBt, *pPgno);
- rc = btreeGetPage(pBt, *pPgno, ppPage, noContent, 0);
+ noContent = !btreeGetHasContent(pBt, *pPgno) ? PAGER_GET_NOCONTENT : 0;
+ rc = btreeGetPage(pBt, *pPgno, ppPage, noContent);
if( rc==SQLITE_OK ){
rc = sqlite3PagerWrite((*ppPage)->pDbPage);
if( rc!=SQLITE_OK ){
@@ -5193,7 +5237,7 @@ static int allocateBtreePage(
** here are confined to those pages that lie between the end of the
** database image and the end of the database file.
*/
- int bNoContent = (0==IfNotOmitAV(pBt->bDoTruncate));
+ int bNoContent = (0==IfNotOmitAV(pBt->bDoTruncate)) ? PAGER_GET_NOCONTENT : 0;
rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
if( rc ) return rc;
@@ -5209,7 +5253,7 @@ static int allocateBtreePage(
MemPage *pPg = 0;
TRACE(("ALLOCATE: %d from end of file (pointer-map page)\n", pBt->nPage));
assert( pBt->nPage!=PENDING_BYTE_PAGE(pBt) );
- rc = btreeGetPage(pBt, pBt->nPage, &pPg, bNoContent, 0);
+ rc = btreeGetPage(pBt, pBt->nPage, &pPg, bNoContent);
if( rc==SQLITE_OK ){
rc = sqlite3PagerWrite(pPg->pDbPage);
releasePage(pPg);
@@ -5223,7 +5267,7 @@ static int allocateBtreePage(
*pPgno = pBt->nPage;
assert( *pPgno!=PENDING_BYTE_PAGE(pBt) );
- rc = btreeGetPage(pBt, *pPgno, ppPage, bNoContent, 0);
+ rc = btreeGetPage(pBt, *pPgno, ppPage, bNoContent);
if( rc ) return rc;
rc = sqlite3PagerWrite((*ppPage)->pDbPage);
if( rc!=SQLITE_OK ){
@@ -5240,6 +5284,7 @@ end_allocate_page:
if( rc==SQLITE_OK ){
if( sqlite3PagerPageRefcount((*ppPage)->pDbPage)>1 ){
releasePage(*ppPage);
+ *ppPage = 0;
return SQLITE_CORRUPT_BKPT;
}
(*ppPage)->isInit = 0;
@@ -5291,7 +5336,7 @@ static int freePage2(BtShared *pBt, MemPage *pMemPage, Pgno iPage){
/* If the secure_delete option is enabled, then
** always fully overwrite deleted information with zeros.
*/
- if( (!pPage && ((rc = btreeGetPage(pBt, iPage, &pPage, 0, 0))!=0) )
+ if( (!pPage && ((rc = btreeGetPage(pBt, iPage, &pPage, 0))!=0) )
|| ((rc = sqlite3PagerWrite(pPage->pDbPage))!=0)
){
goto freepage_out;
@@ -5318,7 +5363,7 @@ static int freePage2(BtShared *pBt, MemPage *pMemPage, Pgno iPage){
u32 nLeaf; /* Initial number of leaf cells on trunk page */
iTrunk = get4byte(&pPage1->aData[32]);
- rc = btreeGetPage(pBt, iTrunk, &pTrunk, 0, 0);
+ rc = btreeGetPage(pBt, iTrunk, &pTrunk, 0);
if( rc!=SQLITE_OK ){
goto freepage_out;
}
@@ -5364,7 +5409,7 @@ static int freePage2(BtShared *pBt, MemPage *pMemPage, Pgno iPage){
** first trunk in the free-list is full. Either way, the page being freed
** will become the new first trunk page in the free-list.
*/
- if( pPage==0 && SQLITE_OK!=(rc = btreeGetPage(pBt, iPage, &pPage, 0, 0)) ){
+ if( pPage==0 && SQLITE_OK!=(rc = btreeGetPage(pBt, iPage, &pPage, 0)) ){
goto freepage_out;
}
rc = sqlite3PagerWrite(pPage->pDbPage);
@@ -5501,7 +5546,7 @@ static int fillInCell(
nHeader += 4;
}
if( pPage->hasData ){
- nHeader += putVarint(&pCell[nHeader], nData+nZero);
+ nHeader += putVarint32(&pCell[nHeader], nData+nZero);
}else{
nData = nZero = 0;
}
@@ -5629,7 +5674,6 @@ static void dropCell(MemPage *pPage, int idx, int sz, int *pRC){
u32 pc; /* Offset to cell content of cell being deleted */
u8 *data; /* pPage->aData */
u8 *ptr; /* Used to move bytes around within data[] */
- u8 *endPtr; /* End of loop */
int rc; /* The return code */
int hdr; /* Beginning of the header. 0 most pages. 100 page 1 */
@@ -5654,13 +5698,8 @@ static void dropCell(MemPage *pPage, int idx, int sz, int *pRC){
*pRC = rc;
return;
}
- endPtr = &pPage->aCellIdx[2*pPage->nCell - 2];
- assert( (SQLITE_PTR_TO_INT(ptr)&1)==0 ); /* ptr is always 2-byte aligned */
- while( ptr<endPtr ){
- *(u16*)ptr = *(u16*)&ptr[2];
- ptr += 2;
- }
pPage->nCell--;
+ memmove(ptr, ptr+2, 2*(pPage->nCell - idx));
put2byte(&data[hdr+3], pPage->nCell);
pPage->nFree += 2;
}
@@ -5697,15 +5736,13 @@ static void insertCell(
int ins; /* Index in data[] where new cell pointer is inserted */
int cellOffset; /* Address of first cell pointer in data[] */
u8 *data; /* The content of the whole page */
- u8 *ptr; /* Used for moving information around in data[] */
- u8 *endPtr; /* End of the loop */
-
int nSkip = (iChild ? 4 : 0);
if( *pRC ) return;
assert( i>=0 && i<=pPage->nCell+pPage->nOverflow );
- assert( pPage->nCell<=MX_CELL(pPage->pBt) && MX_CELL(pPage->pBt)<=10921 );
+ assert( MX_CELL(pPage->pBt)<=10921 );
+ assert( pPage->nCell<=MX_CELL(pPage->pBt) || CORRUPT_DB );
assert( pPage->nOverflow<=ArraySize(pPage->apOvfl) );
assert( ArraySize(pPage->apOvfl)==ArraySize(pPage->aiOvfl) );
assert( sqlite3_mutex_held(pPage->pBt->mutex) );
@@ -5750,13 +5787,7 @@ static void insertCell(
if( iChild ){
put4byte(&data[idx], iChild);
}
- ptr = &data[end];
- endPtr = &data[ins];
- assert( (SQLITE_PTR_TO_INT(ptr)&1)==0 ); /* ptr is always 2-byte aligned */
- while( ptr>endPtr ){
- *(u16*)ptr = *(u16*)&ptr[-2];
- ptr -= 2;
- }
+ memmove(&data[ins+2], &data[ins], end-ins);
put2byte(&data[ins], idx);
put2byte(&data[pPage->hdrOffset+3], pPage->nCell);
#ifndef SQLITE_OMIT_AUTOVACUUM
@@ -6946,7 +6977,7 @@ int sqlite3BtreeInsert(
}
assert( cursorHoldsMutex(pCur) );
- assert( pCur->wrFlag && pBt->inTransaction==TRANS_WRITE
+ assert( (pCur->curFlags & BTCF_WriteFlag)!=0 && pBt->inTransaction==TRANS_WRITE
&& (pBt->btsFlags & BTS_READ_ONLY)==0 );
assert( hasSharedCacheTableLock(p, pCur->pgnoRoot, pCur->pKeyInfo!=0, 2) );
@@ -6971,11 +7002,17 @@ int sqlite3BtreeInsert(
rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur);
if( rc ) return rc;
- /* If this is an insert into a table b-tree, invalidate any incrblob
- ** cursors open on the row being replaced (assuming this is a replace
- ** operation - if it is not, the following is a no-op). */
if( pCur->pKeyInfo==0 ){
+ /* If this is an insert into a table b-tree, invalidate any incrblob
+ ** cursors open on the row being replaced */
invalidateIncrblobCursors(p, nKey, 0);
+
+ /* If the cursor is currently on the last row and we are appending a
+ ** new row onto the end, set the "loc" to avoid an unnecessary btreeMoveto()
+ ** call */
+ if( (pCur->curFlags&BTCF_ValidNKey)!=0 && nKey>0 && pCur->info.nKey==nKey-1 ){
+ loc = -1;
+ }
}
if( !loc ){
@@ -7026,7 +7063,7 @@ int sqlite3BtreeInsert(
/* If no error has occurred and pPage has an overflow cell, call balance()
** to redistribute the cells within the tree. Since balance() may move
- ** the cursor, zero the BtCursor.info.nSize and BtCursor.validNKey
+ ** the cursor, zero the BtCursor.info.nSize and BTCF_ValidNKey
** variables.
**
** Previous versions of SQLite called moveToRoot() to move the cursor
@@ -7045,8 +7082,8 @@ int sqlite3BtreeInsert(
** row without seeking the cursor. This can be a big performance boost.
*/
pCur->info.nSize = 0;
- pCur->validNKey = 0;
if( rc==SQLITE_OK && pPage->nOverflow ){
+ pCur->curFlags &= ~(BTCF_ValidNKey);
rc = balance(pCur);
/* Must make sure nOverflow is reset to zero even if the balance()
@@ -7078,7 +7115,7 @@ int sqlite3BtreeDelete(BtCursor *pCur){
assert( cursorHoldsMutex(pCur) );
assert( pBt->inTransaction==TRANS_WRITE );
assert( (pBt->btsFlags & BTS_READ_ONLY)==0 );
- assert( pCur->wrFlag );
+ assert( pCur->curFlags & BTCF_WriteFlag );
assert( hasSharedCacheTableLock(p, pCur->pgnoRoot, pCur->pKeyInfo!=0, 2) );
assert( !hasReadConflicts(p, pCur->pgnoRoot) );
@@ -7101,7 +7138,7 @@ int sqlite3BtreeDelete(BtCursor *pCur){
** sub-tree headed by the child page of the cell being deleted. This makes
** balancing the tree following the delete operation easier. */
if( !pPage->leaf ){
- int notUsed;
+ int notUsed = 0;
rc = sqlite3BtreePrevious(pCur, &notUsed);
if( rc ) return rc;
}
@@ -7263,7 +7300,7 @@ static int btreeCreateTable(Btree *p, int *piTable, int createTabFlags){
}
/* Move the page currently at pgnoRoot to pgnoMove. */
- rc = btreeGetPage(pBt, pgnoRoot, &pRoot, 0, 0);
+ rc = btreeGetPage(pBt, pgnoRoot, &pRoot, 0);
if( rc!=SQLITE_OK ){
return rc;
}
@@ -7284,7 +7321,7 @@ static int btreeCreateTable(Btree *p, int *piTable, int createTabFlags){
if( rc!=SQLITE_OK ){
return rc;
}
- rc = btreeGetPage(pBt, pgnoRoot, &pRoot, 0, 0);
+ rc = btreeGetPage(pBt, pgnoRoot, &pRoot, 0);
if( rc!=SQLITE_OK ){
return rc;
}
@@ -7354,6 +7391,7 @@ static int clearDatabasePage(
int rc;
unsigned char *pCell;
int i;
+ int hdr;
assert( sqlite3_mutex_held(pBt->mutex) );
if( pgno>btreePagecount(pBt) ){
@@ -7362,6 +7400,7 @@ static int clearDatabasePage(
rc = getAndInitPage(pBt, pgno, &pPage, 0);
if( rc ) return rc;
+ hdr = pPage->hdrOffset;
for(i=0; i<pPage->nCell; i++){
pCell = findCell(pPage, i);
if( !pPage->leaf ){
@@ -7372,7 +7411,7 @@ static int clearDatabasePage(
if( rc ) goto cleardatabasepage_out;
}
if( !pPage->leaf ){
- rc = clearDatabasePage(pBt, get4byte(&pPage->aData[8]), 1, pnChange);
+ rc = clearDatabasePage(pBt, get4byte(&pPage->aData[hdr+8]), 1, pnChange);
if( rc ) goto cleardatabasepage_out;
}else if( pnChange ){
assert( pPage->intKey );
@@ -7381,7 +7420,7 @@ static int clearDatabasePage(
if( freePageFlag ){
freePage(pPage, &rc);
}else if( (rc = sqlite3PagerWrite(pPage->pDbPage))==0 ){
- zeroPage(pPage, pPage->aData[0] | PTF_LEAF);
+ zeroPage(pPage, pPage->aData[hdr] | PTF_LEAF);
}
cleardatabasepage_out:
@@ -7422,6 +7461,15 @@ int sqlite3BtreeClearTable(Btree *p, int iTable, int *pnChange){
}
/*
+** Delete all information from the single table that pCur is open on.
+**
+** This routine only work for pCur on an ephemeral table.
+*/
+int sqlite3BtreeClearTableOfCursor(BtCursor *pCur){
+ return sqlite3BtreeClearTable(pCur->pBtree, pCur->pgnoRoot, 0);
+}
+
+/*
** Erase all information in a table and add the root of the table to
** the freelist. Except, the root of the principle table (the one on
** page 1) is never added to the freelist.
@@ -7462,7 +7510,7 @@ static int btreeDropTable(Btree *p, Pgno iTable, int *piMoved){
return SQLITE_LOCKED_SHAREDCACHE;
}
- rc = btreeGetPage(pBt, (Pgno)iTable, &pPage, 0, 0);
+ rc = btreeGetPage(pBt, (Pgno)iTable, &pPage, 0);
if( rc ) return rc;
rc = sqlite3BtreeClearTable(p, iTable, 0);
if( rc ){
@@ -7497,7 +7545,7 @@ static int btreeDropTable(Btree *p, Pgno iTable, int *piMoved){
*/
MemPage *pMove;
releasePage(pPage);
- rc = btreeGetPage(pBt, maxRootPgno, &pMove, 0, 0);
+ rc = btreeGetPage(pBt, maxRootPgno, &pMove, 0);
if( rc!=SQLITE_OK ){
return rc;
}
@@ -7507,7 +7555,7 @@ static int btreeDropTable(Btree *p, Pgno iTable, int *piMoved){
return rc;
}
pMove = 0;
- rc = btreeGetPage(pBt, maxRootPgno, &pMove, 0, 0);
+ rc = btreeGetPage(pBt, maxRootPgno, &pMove, 0);
freePage(pMove, &rc);
releasePage(pMove);
if( rc!=SQLITE_OK ){
@@ -7718,11 +7766,11 @@ static void checkAppendMsg(
sqlite3StrAccumAppend(&pCheck->errMsg, "\n", 1);
}
if( zMsg1 ){
- sqlite3StrAccumAppend(&pCheck->errMsg, zMsg1, -1);
+ sqlite3StrAccumAppendAll(&pCheck->errMsg, zMsg1);
}
sqlite3VXPrintf(&pCheck->errMsg, 1, zFormat, ap);
va_end(ap);
- if( pCheck->errMsg.mallocFailed ){
+ if( pCheck->errMsg.accError==STRACCUM_NOMEM ){
pCheck->mallocFailed = 1;
}
}
@@ -7919,7 +7967,7 @@ static int checkTreePage(
usableSize = pBt->usableSize;
if( iPage==0 ) return 0;
if( checkRef(pCheck, iPage, zParentContext) ) return 0;
- if( (rc = btreeGetPage(pBt, (Pgno)iPage, &pPage, 0, 0))!=0 ){
+ if( (rc = btreeGetPage(pBt, (Pgno)iPage, &pPage, 0))!=0 ){
checkAppendMsg(pCheck, zContext,
"unable to get the page. error code=%d", rc);
return 0;
@@ -8380,7 +8428,7 @@ int sqlite3BtreePutData(BtCursor *pCsr, u32 offset, u32 amt, void *z){
int rc;
assert( cursorHoldsMutex(pCsr) );
assert( sqlite3_mutex_held(pCsr->pBtree->db->mutex) );
- assert( pCsr->isIncrblobHandle );
+ assert( pCsr->curFlags & BTCF_Incrblob );
rc = restoreCursorPosition(pCsr);
if( rc!=SQLITE_OK ){
@@ -8409,7 +8457,7 @@ int sqlite3BtreePutData(BtCursor *pCsr, u32 offset, u32 amt, void *z){
** (d) there are no conflicting read-locks, and
** (e) the cursor points at a valid row of an intKey table.
*/
- if( !pCsr->wrFlag ){
+ if( (pCsr->curFlags & BTCF_WriteFlag)==0 ){
return SQLITE_READONLY;
}
assert( (pCsr->pBt->btsFlags & BTS_READ_ONLY)==0
@@ -8422,20 +8470,10 @@ int sqlite3BtreePutData(BtCursor *pCsr, u32 offset, u32 amt, void *z){
}
/*
-** Set a flag on this cursor to cache the locations of pages from the
-** overflow list for the current row. This is used by cursors opened
-** for incremental blob IO only.
-**
-** This function sets a flag only. The actual page location cache
-** (stored in BtCursor.aOverflow[]) is allocated and used by function
-** accessPayload() (the worker function for sqlite3BtreeData() and
-** sqlite3BtreePutData()).
+** Mark this cursor as an incremental blob cursor.
*/
-void sqlite3BtreeCacheOverflow(BtCursor *pCur){
- assert( cursorHoldsMutex(pCur) );
- assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
- invalidateOverflowCache(pCur);
- pCur->isIncrblobHandle = 1;
+void sqlite3BtreeIncrblobCursor(BtCursor *pCur){
+ pCur->curFlags |= BTCF_Incrblob;
}
#endif
@@ -8483,3 +8521,10 @@ void sqlite3BtreeCursorHints(BtCursor *pCsr, unsigned int mask){
assert( mask==BTREE_BULKLOAD || mask==0 );
pCsr->hints = mask;
}
+
+/*
+** Return true if the given Btree is read-only.
+*/
+int sqlite3BtreeIsReadonly(Btree *p){
+ return (p->pBt->btsFlags & BTS_READ_ONLY)!=0;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-09 05:54:06 +0000