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-rw-r--r--src/vdbe.c251
1 files changed, 131 insertions, 120 deletions
diff --git a/src/vdbe.c b/src/vdbe.c
index 874645f18..f3832ab34 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -2255,13 +2255,11 @@ case OP_NotNull: { /* same as TK_NOTNULL, jump, in1 */
*/
case OP_Column: {
i64 payloadSize64; /* Number of bytes in the record */
- int p1; /* P1 value of the opcode */
int p2; /* column number to retrieve */
VdbeCursor *pC; /* The VDBE cursor */
BtCursor *pCrsr; /* The BTree cursor */
u32 *aType; /* aType[i] holds the numeric type of the i-th column */
u32 *aOffset; /* aOffset[i] is offset to start of data for i-th column */
- int nField; /* number of fields in the record */
int len; /* The length of the serialized data for the column */
int i; /* Loop counter */
Mem *pDest; /* Where to write the extracted value */
@@ -2275,17 +2273,14 @@ case OP_Column: {
u32 t; /* A type code from the record header */
Mem *pReg; /* PseudoTable input register */
- p1 = pOp->p1;
- assert( p1<p->nCursor );
p2 = pOp->p2;
- sMem.zMalloc = 0;
assert( pOp->p3>0 && pOp->p3<=(p->nMem-p->nCursor) );
pDest = &aMem[pOp->p3];
memAboutToChange(p, pDest);
- pC = p->apCsr[p1];
+ assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+ pC = p->apCsr[pOp->p1];
assert( pC!=0 );
- nField = pC->nField;
- assert( p2<nField );
+ assert( p2<pC->nField );
aType = pC->aType;
aOffset = pC->aOffset;
#ifndef SQLITE_OMIT_VIRTUALTABLE
@@ -2293,27 +2288,31 @@ case OP_Column: {
#endif
pCrsr = pC->pCursor;
assert( pCrsr!=0 || pC->pseudoTableReg>0 );
+ assert( pC->pseudoTableReg==0 || pC->nullRow );
/* If the cursor cache is stale, bring it up-to-date */
rc = sqlite3VdbeCursorMoveto(pC);
if( rc ) goto abort_due_to_error;
if( pC->cacheStatus!=p->cacheCtr || (pOp->p5&OPFLAG_CLEARCACHE)!=0 ){
- if( pCrsr==0 ){
- assert( pC->pseudoTableReg>0 );
- pReg = &aMem[pC->pseudoTableReg];
- if( pC->multiPseudo ){
- sqlite3VdbeMemShallowCopy(pDest, pReg+p2, MEM_Ephem);
- Deephemeralize(pDest);
+ if( pC->nullRow ){
+ if( pCrsr==0 ){
+ assert( pC->pseudoTableReg>0 );
+ pReg = &aMem[pC->pseudoTableReg];
+ if( pC->multiPseudo ){
+ sqlite3VdbeMemShallowCopy(pDest, pReg+p2, MEM_Ephem);
+ Deephemeralize(pDest);
+ goto op_column_out;
+ }
+ assert( pReg->flags & MEM_Blob );
+ assert( memIsValid(pReg) );
+ pC->payloadSize = pC->szRow = avail = pReg->n;
+ pC->aRow = (u8*)pReg->z;
+ }else{
+ MemSetTypeFlag(pDest, MEM_Null);
goto op_column_out;
}
- assert( pReg->flags & MEM_Blob );
- assert( memIsValid(pReg) );
- pC->payloadSize = pC->szRow = avail = pReg->n;
- pC->aRow = (u8*)pReg->z;
- }else if( pC->nullRow ){
- MemSetTypeFlag(pDest, MEM_Null);
- goto op_column_out;
}else{
+ assert( pCrsr );
if( pC->isIndex ){
assert( sqlite3BtreeCursorIsValid(pCrsr) );
VVA_ONLY(rc =) sqlite3BtreeKeySize(pCrsr, &payloadSize64);
@@ -2361,65 +2360,85 @@ case OP_Column: {
*/
if( offset > 98307 || offset > pC->payloadSize ){
rc = SQLITE_CORRUPT_BKPT;
- goto op_column_out;
+ goto op_column_error;
}
}
/* Make sure at least the first p2+1 entries of the header have been
** parsed and valid information is in aOffset[] and aType[].
*/
- if( pC->nHdrParsed<=p2 && pC->iHdrOffset<aOffset[0] ){
- /* Make sure zData points to enough of the record to cover the header. */
- if( pC->aRow==0 ){
- memset(&sMem, 0, sizeof(sMem));
- rc = sqlite3VdbeMemFromBtree(pCrsr, 0, pC->aOffset[0], pC->isIndex,&sMem);
- if( rc!=SQLITE_OK ){
- goto op_column_out;
- }
- zData = (u8*)sMem.z;
- }else{
- zData = pC->aRow;
- }
-
- /* Fill in aType[i] and aOffset[i] values through the p2-th field. */
- i = pC->nHdrParsed;
- offset = aOffset[i];
- zHdr = zData + pC->iHdrOffset;
- zEndHdr = zData + pC->aOffset[0];
- for(; i<=p2 && zHdr<zEndHdr; i++){
- if( zHdr[0]<0x80 ){
- t = zHdr[0];
- zHdr++;
+ if( pC->nHdrParsed<=p2 ){
+ /* If there is more header available for parsing, try to extract
+ ** additional fields up through the p2-th field
+ */
+ if( pC->iHdrOffset<aOffset[0] ){
+ /* Make sure zData points to enough of the record to cover the header. */
+ if( pC->aRow==0 ){
+ memset(&sMem, 0, sizeof(sMem));
+ rc = sqlite3VdbeMemFromBtree(pCrsr, 0, pC->aOffset[0], pC->isIndex,
+ &sMem);
+ if( rc!=SQLITE_OK ){
+ goto op_column_error;
+ }
+ zData = (u8*)sMem.z;
}else{
- zHdr += sqlite3GetVarint32(zHdr, &t);
+ zData = pC->aRow;
}
- aType[i] = t;
- szField = sqlite3VdbeSerialTypeLen(t);
- offset += szField;
- if( offset<szField ){ /* True if offset overflows */
- zHdr = &zEndHdr[1]; /* Forces SQLITE_CORRUPT return below */
- break;
+
+ /* Fill in aType[i] and aOffset[i] values through the p2-th field. */
+ i = pC->nHdrParsed;
+ offset = aOffset[i];
+ zHdr = zData + pC->iHdrOffset;
+ zEndHdr = zData + aOffset[0];
+ assert( i<=p2 && zHdr<zEndHdr );
+ do{
+ if( zHdr[0]<0x80 ){
+ t = zHdr[0];
+ zHdr++;
+ }else{
+ zHdr += sqlite3GetVarint32(zHdr, &t);
+ }
+ aType[i] = t;
+ szField = sqlite3VdbeSerialTypeLen(t);
+ offset += szField;
+ if( offset<szField ){ /* True if offset overflows */
+ zHdr = &zEndHdr[1]; /* Forces SQLITE_CORRUPT return below */
+ break;
+ }
+ i++;
+ aOffset[i] = offset;
+ }while( i<=p2 && zHdr<zEndHdr );
+ pC->nHdrParsed = i;
+ pC->iHdrOffset = (u32)(zHdr - zData);
+ if( pC->aRow==0 ){
+ sqlite3VdbeMemRelease(&sMem);
+ sMem.flags = MEM_Null;
+ }
+
+ /* If we have read more header data than was contained in the header,
+ ** or if the end of the last field appears to be past the end of the
+ ** record, or if the end of the last field appears to be before the end
+ ** of the record (when all fields present), then we must be dealing
+ ** with a corrupt database.
+ */
+ if( (zHdr > zEndHdr)
+ || (offset > pC->payloadSize)
+ || (zHdr==zEndHdr && offset!=pC->payloadSize)
+ ){
+ rc = SQLITE_CORRUPT_BKPT;
+ goto op_column_error;
}
- aOffset[i+1] = offset;
- }
- pC->nHdrParsed = i;
- pC->iHdrOffset = (u32)(zHdr - zData);
- if( pC->aRow==0 ){
- sqlite3VdbeMemRelease(&sMem);
- sMem.flags = MEM_Null;
}
- /* If we have read more header data than was contained in the header,
- ** or if the end of the last field appears to be past the end of the
- ** record, or if the end of the last field appears to be before the end
- ** of the record (when all fields present), then we must be dealing
- ** with a corrupt database.
- */
- if( (zHdr > zEndHdr)
- || (offset > pC->payloadSize)
- || (zHdr==zEndHdr && offset!=pC->payloadSize)
- ){
- rc = SQLITE_CORRUPT_BKPT;
+ /* If after nHdrParsed is still not up to p2, that means that the record
+ ** has fewer than p2 columns. So the result will be either the default
+ ** value or a NULL. */
+ if( pC->nHdrParsed<=p2 ){
+ if( pOp->p4type==P4_MEM ){
+ sqlite3VdbeMemShallowCopy(pDest, pOp->p4.pMem, MEM_Static);
+ }else{
+ MemSetTypeFlag(pDest, MEM_Null);
+ }
goto op_column_out;
}
}
@@ -2430,64 +2449,56 @@ case OP_Column: {
** request. In this case, set the value NULL or to P4 if P4 is
** a pointer to a Mem object.
*/
- if( p2<pC->nHdrParsed ){
- assert( rc==SQLITE_OK );
- if( pC->szRow>=aOffset[p2+1] ){
- /* This is the common case where the whole row fits on a single page */
- VdbeMemRelease(pDest);
- sqlite3VdbeSerialGet(pC->aRow+aOffset[p2], aType[p2], pDest);
+ assert( p2<pC->nHdrParsed );
+ assert( rc==SQLITE_OK );
+ if( pC->szRow>=aOffset[p2+1] ){
+ /* This is the common case where the whole row fits on a single page */
+ VdbeMemRelease(pDest);
+ sqlite3VdbeSerialGet(pC->aRow+aOffset[p2], aType[p2], pDest);
+ }else{
+ /* This branch happens only when the row overflows onto multiple pages */
+ t = aType[p2];
+ if( (pOp->p5 & (OPFLAG_LENGTHARG|OPFLAG_TYPEOFARG))!=0
+ && ((t>=12 && (t&1)==0) || (pOp->p5 & OPFLAG_TYPEOFARG)!=0)
+ ){
+ /* Content is irrelevant for the typeof() function and for
+ ** the length(X) function if X is a blob. So we might as well use
+ ** bogus content rather than reading content from disk. NULL works
+ ** for text and blob and whatever is in the payloadSize64 variable
+ ** will work for everything else. */
+ zData = t<12 ? (u8*)&payloadSize64 : 0;
+ sMem.zMalloc = 0;
}else{
- /* This branch happens only when the row overflows onto multiple pages */
- t = aType[p2];
- if( (pOp->p5 & (OPFLAG_LENGTHARG|OPFLAG_TYPEOFARG))!=0
- && ((t>=12 && (t&1)==0) || (pOp->p5 & OPFLAG_TYPEOFARG)!=0)
- ){
- /* Content is irrelevant for the typeof() function and for
- ** the length(X) function if X is a blob. So we might as well use
- ** bogus content rather than reading content from disk. NULL works
- ** for text and blob and whatever is in the payloadSize64 variable
- ** will work for everything else. */
- zData = t<12 ? (u8*)&payloadSize64 : 0;
- }else{
- len = sqlite3VdbeSerialTypeLen(t);
- memset(&sMem, 0, sizeof(sMem));
- sqlite3VdbeMemMove(&sMem, pDest);
- rc = sqlite3VdbeMemFromBtree(pCrsr, aOffset[p2], len, pC->isIndex,
- &sMem);
- if( rc!=SQLITE_OK ){
- goto op_column_out;
- }
- zData = (u8*)sMem.z;
+ len = sqlite3VdbeSerialTypeLen(t);
+ memset(&sMem, 0, sizeof(sMem));
+ sqlite3VdbeMemMove(&sMem, pDest);
+ rc = sqlite3VdbeMemFromBtree(pCrsr, aOffset[p2], len, pC->isIndex,
+ &sMem);
+ if( rc!=SQLITE_OK ){
+ goto op_column_error;
}
- sqlite3VdbeSerialGet(zData, t, pDest);
+ zData = (u8*)sMem.z;
}
- pDest->enc = encoding;
- }else{
- if( pOp->p4type==P4_MEM ){
- sqlite3VdbeMemShallowCopy(pDest, pOp->p4.pMem, MEM_Static);
- }else{
- MemSetTypeFlag(pDest, MEM_Null);
+ sqlite3VdbeSerialGet(zData, t, pDest);
+ /* If we dynamically allocated space to hold the data (in the
+ ** sqlite3VdbeMemFromBtree() call above) then transfer control of that
+ ** dynamically allocated space over to the pDest structure.
+ ** This prevents a memory copy. */
+ if( sMem.zMalloc ){
+ assert( sMem.z==sMem.zMalloc );
+ assert( !(pDest->flags & MEM_Dyn) );
+ assert( !(pDest->flags & (MEM_Blob|MEM_Str)) || pDest->z==sMem.z );
+ pDest->flags &= ~(MEM_Ephem|MEM_Static);
+ pDest->flags |= MEM_Term;
+ pDest->z = sMem.z;
+ pDest->zMalloc = sMem.zMalloc;
}
}
-
- /* If we dynamically allocated space to hold the data (in the
- ** sqlite3VdbeMemFromBtree() call above) then transfer control of that
- ** dynamically allocated space over to the pDest structure.
- ** This prevents a memory copy.
- */
- if( sMem.zMalloc ){
- assert( sMem.z==sMem.zMalloc );
- assert( !(pDest->flags & MEM_Dyn) );
- assert( !(pDest->flags & (MEM_Blob|MEM_Str)) || pDest->z==sMem.z );
- pDest->flags &= ~(MEM_Ephem|MEM_Static);
- pDest->flags |= MEM_Term;
- pDest->z = sMem.z;
- pDest->zMalloc = sMem.zMalloc;
- }
-
- rc = sqlite3VdbeMemMakeWriteable(pDest);
+ pDest->enc = encoding;
op_column_out:
+ rc = sqlite3VdbeMemMakeWriteable(pDest);
+op_column_error:
UPDATE_MAX_BLOBSIZE(pDest);
REGISTER_TRACE(pOp->p3, pDest);
break;
generated by cgit v1.2.3 (git 2.25.1) at 2025-07-19 08:02:39 +0000