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-rw-r--r--src/select.c77
1 files changed, 56 insertions, 21 deletions
diff --git a/src/select.c b/src/select.c
index c54837ba1..2d985d6c3 100644
--- a/src/select.c
+++ b/src/select.c
@@ -805,13 +805,9 @@ static void selectInnerLoop(
/*
** Allocate a KeyInfo object sufficient for an index of N key columns and
** X extra columns.
-**
-** Actually, always allocate one extra column for the rowid at the end
-** of the index. So the KeyInfo returned will have space sufficient for
-** N+1 columns.
*/
KeyInfo *sqlite3KeyInfoAlloc(sqlite3 *db, int N, int X){
- KeyInfo *p = sqlite3DbMallocZero(db,
+ KeyInfo *p = sqlite3DbMallocZero(0,
sizeof(KeyInfo) + (N+X)*(sizeof(CollSeq*)+1));
if( p ){
p->aSortOrder = (u8*)&p->aColl[N+X];
@@ -819,11 +815,47 @@ KeyInfo *sqlite3KeyInfoAlloc(sqlite3 *db, int N, int X){
p->nXField = (u16)X;
p->enc = ENC(db);
p->db = db;
+ p->nRef = 1;
+ }else{
+ db->mallocFailed = 1;
}
return p;
}
/*
+** Deallocate a KeyInfo object
+*/
+void sqlite3KeyInfoUnref(KeyInfo *p){
+ if( p ){
+ assert( p->nRef>0 );
+ assert( p->db==0 || p->db->pnBytesFreed==0 );
+ p->nRef--;
+ if( p->nRef==0 ) sqlite3DbFree(p->db, p);
+ }
+}
+
+/*
+** Make a new pointer to a KeyInfo object
+*/
+KeyInfo *sqlite3KeyInfoRef(KeyInfo *p){
+ if( p ){
+ assert( p->nRef>0 );
+ p->nRef++;
+ }
+ return p;
+}
+
+#ifdef SQLITE_DEBUG
+/*
+** Return TRUE if a KeyInfo object can be change. The KeyInfo object
+** can only be changed if this is just a single reference to the object.
+**
+** This routine is used only inside of assert() statements.
+*/
+int sqlite3KeyInfoIsWriteable(KeyInfo *p){ return p->nRef==1; }
+#endif /* SQLITE_DEBUG */
+
+/*
** Given an expression list, generate a KeyInfo structure that records
** the collating sequence for each expression in that expression list.
**
@@ -835,8 +867,7 @@ KeyInfo *sqlite3KeyInfoAlloc(sqlite3 *db, int N, int X){
**
** Space to hold the KeyInfo structure is obtain from malloc. The calling
** function is responsible for seeing that this structure is eventually
-** freed. Add the KeyInfo structure to the P4 field of an opcode using
-** P4_KEYINFO_HANDOFF is the usual way of dealing with this.
+** freed.
*/
static KeyInfo *keyInfoFromExprList(Parse *pParse, ExprList *pList){
int nExpr;
@@ -848,6 +879,7 @@ static KeyInfo *keyInfoFromExprList(Parse *pParse, ExprList *pList){
nExpr = pList->nExpr;
pInfo = sqlite3KeyInfoAlloc(db, nExpr, 1);
if( pInfo ){
+ assert( sqlite3KeyInfoIsWriteable(pInfo) );
for(i=0, pItem=pList->a; i<nExpr; i++, pItem++){
CollSeq *pColl;
pColl = sqlite3ExprCollSeq(pParse, pItem->pExpr);
@@ -2012,11 +2044,12 @@ static int multiSelect(
break;
}
sqlite3VdbeChangeP2(v, addr, nCol);
- sqlite3VdbeChangeP4(v, addr, (char*)pKeyInfo, P4_KEYINFO);
+ sqlite3VdbeChangeP4(v, addr, (char*)sqlite3KeyInfoRef(pKeyInfo),
+ P4_KEYINFO);
pLoop->addrOpenEphm[i] = -1;
}
}
- sqlite3DbFree(db, pKeyInfo);
+ sqlite3KeyInfoUnref(pKeyInfo);
}
multi_select_end:
@@ -2055,7 +2088,6 @@ static int generateOutputSubroutine(
int regReturn, /* The return address register */
int regPrev, /* Previous result register. No uniqueness if 0 */
KeyInfo *pKeyInfo, /* For comparing with previous entry */
- int p4type, /* The p4 type for pKeyInfo */
int iBreak /* Jump here if we hit the LIMIT */
){
Vdbe *v = pParse->pVdbe;
@@ -2071,7 +2103,7 @@ static int generateOutputSubroutine(
int j1, j2;
j1 = sqlite3VdbeAddOp1(v, OP_IfNot, regPrev);
j2 = sqlite3VdbeAddOp4(v, OP_Compare, pIn->iSdst, regPrev+1, pIn->nSdst,
- (char*)pKeyInfo, p4type);
+ (char*)sqlite3KeyInfoRef(pKeyInfo), P4_KEYINFO);
sqlite3VdbeAddOp3(v, OP_Jump, j2+2, iContinue, j2+2);
sqlite3VdbeJumpHere(v, j1);
sqlite3VdbeAddOp3(v, OP_Copy, pIn->iSdst, regPrev+1, pIn->nSdst-1);
@@ -2382,6 +2414,7 @@ static int multiSelectOrderBy(
pOrderBy->a[i].pExpr =
sqlite3ExprAddCollateString(pParse, pTerm, pColl->zName);
}
+ assert( sqlite3KeyInfoIsWriteable(pKeyMerge) );
pKeyMerge->aColl[i] = pColl;
pKeyMerge->aSortOrder[i] = pOrderBy->a[i].sortOrder;
}
@@ -2409,6 +2442,7 @@ static int multiSelectOrderBy(
sqlite3VdbeAddOp2(v, OP_Integer, 0, regPrev);
pKeyDup = sqlite3KeyInfoAlloc(db, nExpr, 1);
if( pKeyDup ){
+ assert( sqlite3KeyInfoIsWriteable(pKeyDup) );
for(i=0; i<nExpr; i++){
pKeyDup->aColl[i] = multiSelectCollSeq(pParse, p, i);
pKeyDup->aSortOrder[i] = 0;
@@ -2490,7 +2524,7 @@ static int multiSelectOrderBy(
VdbeNoopComment((v, "Output routine for A"));
addrOutA = generateOutputSubroutine(pParse,
p, &destA, pDest, regOutA,
- regPrev, pKeyDup, P4_KEYINFO_HANDOFF, labelEnd);
+ regPrev, pKeyDup, labelEnd);
/* Generate a subroutine that outputs the current row of the B
** select as the next output row of the compound select.
@@ -2499,8 +2533,9 @@ static int multiSelectOrderBy(
VdbeNoopComment((v, "Output routine for B"));
addrOutB = generateOutputSubroutine(pParse,
p, &destB, pDest, regOutB,
- regPrev, pKeyDup, P4_KEYINFO_STATIC, labelEnd);
+ regPrev, pKeyDup, labelEnd);
}
+ sqlite3KeyInfoUnref(pKeyDup);
/* Generate a subroutine to run when the results from select A
** are exhausted and only data in select B remains.
@@ -2579,7 +2614,7 @@ static int multiSelectOrderBy(
sqlite3VdbeResolveLabel(v, labelCmpr);
sqlite3VdbeAddOp4(v, OP_Permutation, 0, 0, 0, (char*)aPermute, P4_INTARRAY);
sqlite3VdbeAddOp4(v, OP_Compare, destA.iSdst, destB.iSdst, nOrderBy,
- (char*)pKeyMerge, P4_KEYINFO_HANDOFF);
+ (char*)pKeyMerge, P4_KEYINFO);
sqlite3VdbeChangeP5(v, OPFLAG_PERMUTE);
sqlite3VdbeAddOp3(v, OP_Jump, addrAltB, addrAeqB, addrAgtB);
@@ -3805,7 +3840,7 @@ static void resetAccumulator(Parse *pParse, AggInfo *pAggInfo){
}else{
KeyInfo *pKeyInfo = keyInfoFromExprList(pParse, pE->x.pList);
sqlite3VdbeAddOp4(v, OP_OpenEphemeral, pFunc->iDistinct, 0, 0,
- (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
+ (char*)pKeyInfo, P4_KEYINFO);
}
}
}
@@ -4260,7 +4295,7 @@ int sqlite3Select(
p->addrOpenEphm[2] = addrSortIndex =
sqlite3VdbeAddOp4(v, OP_OpenEphemeral,
pOrderBy->iECursor, pOrderBy->nExpr+2, 0,
- (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
+ (char*)pKeyInfo, P4_KEYINFO);
}else{
addrSortIndex = -1;
}
@@ -4288,7 +4323,7 @@ int sqlite3Select(
sDistinct.addrTnct = sqlite3VdbeAddOp4(v, OP_OpenEphemeral,
sDistinct.tabTnct, 0, 0,
(char*)keyInfoFromExprList(pParse, p->pEList),
- P4_KEYINFO_HANDOFF);
+ P4_KEYINFO);
sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
sDistinct.eTnctType = WHERE_DISTINCT_UNORDERED;
}else{
@@ -4412,7 +4447,7 @@ int sqlite3Select(
pKeyInfo = keyInfoFromExprList(pParse, pGroupBy);
addrSortingIdx = sqlite3VdbeAddOp4(v, OP_SorterOpen,
sAggInfo.sortingIdx, sAggInfo.nSortingColumn,
- 0, (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
+ 0, (char*)pKeyInfo, P4_KEYINFO);
/* Initialize memory locations used by GROUP BY aggregate processing
*/
@@ -4526,7 +4561,7 @@ int sqlite3Select(
}
}
sqlite3VdbeAddOp4(v, OP_Compare, iAMem, iBMem, pGroupBy->nExpr,
- (char*)pKeyInfo, P4_KEYINFO);
+ (char*)sqlite3KeyInfoRef(pKeyInfo), P4_KEYINFO);
j1 = sqlite3VdbeCurrentAddr(v);
sqlite3VdbeAddOp3(v, OP_Jump, j1+1, 0, j1+1);
@@ -4652,13 +4687,13 @@ int sqlite3Select(
}
if( pBest ){
iRoot = pBest->tnum;
- pKeyInfo = sqlite3IndexKeyinfo(pParse, pBest);
+ pKeyInfo = sqlite3KeyInfoOfIndex(pParse, pBest);
}
/* Open a read-only cursor, execute the OP_Count, close the cursor. */
sqlite3VdbeAddOp4Int(v, OP_OpenRead, iCsr, iRoot, iDb, 1);
if( pKeyInfo ){
- sqlite3VdbeChangeP4(v, -1, (char *)pKeyInfo, P4_KEYINFO_HANDOFF);
+ sqlite3VdbeChangeP4(v, -1, (char *)pKeyInfo, P4_KEYINFO);
}
sqlite3VdbeAddOp2(v, OP_Count, iCsr, sAggInfo.aFunc[0].iMem);
sqlite3VdbeAddOp1(v, OP_Close, iCsr);