/*
** Delete any previous value and set the value stored in *pMem to NULL.
*/
void sqlite3VdbeMemSetNull(Mem *pMem){
if( pMem->flags & MEM_RowSet ){
sqlite3RowSetClear(pMem->u.pRowSet);
}
MemSetTypeFlag(pMem, MEM_Null);
pMem->type = SQLITE_NULL;
}
/*
** Extract the smallest element from the RowSet.
** Write the element into *pRowid. Return 1 on success. Return
** 0 if the RowSet is already empty.
**
** After this routine has been called, the sqlite3RowSetInsert()
** routine may not be called again.
**
** This routine may not be called after sqlite3RowSetTest() has
** been used. Older versions of RowSet allowed that, but as the
** capability was not used by the code generator, it was removed
** for code economy.
*/
int sqlite3RowSetNext(RowSet *p, i64 *pRowid){
assert( p!=0 );
assert( p->pForest==0 ); /* Cannot be used with sqlite3RowSetText() */
/* Merge the forest into a single sorted list on first call */
if( (p->rsFlags & ROWSET_NEXT)==0 ){ /*OPTIMIZATION-IF-FALSE*/
if( (p->rsFlags & ROWSET_SORTED)==0 ){ /*OPTIMIZATION-IF-FALSE*/
p->pEntry = rowSetEntrySort(p->pEntry);
}
p->rsFlags |= ROWSET_SORTED|ROWSET_NEXT;
}
/* Return the next entry on the list */
if( p->pEntry ){
*pRowid = p->pEntry->v;
p->pEntry = p->pEntry->pRight;
if( p->pEntry==0 ){ /*OPTIMIZATION-IF-TRUE*/
/* Free memory immediately, rather than waiting on sqlite3_finalize() */
sqlite3RowSetClear(p);
}
return 1;
}else{
return 0;
}
}
/*
** Delete any previous value and set the value stored in *pMem to NULL.
*/
void sqlite3VdbeMemSetNull(Mem *pMem){
if( pMem->flags & MEM_Frame ){
VdbeFrame *pFrame = pMem->u.pFrame;
pFrame->pParent = pFrame->v->pDelFrame;
pFrame->v->pDelFrame = pFrame;
}
if( pMem->flags & MEM_RowSet ){
sqlite3RowSetClear(pMem->u.pRowSet);
}
MemSetTypeFlag(pMem, MEM_Null);
pMem->type = SQLITE_NULL;
}
/*
** Extract the smallest element from the RowSet.
** Write the element into *pRowid. Return 1 on success. Return
** 0 if the RowSet is already empty.
**
** After this routine has been called, the sqlite3RowSetInsert()
** routine may not be called again.
*/
int sqlite3RowSetNext(RowSet *p, i64 *pRowid){
rowSetToList(p);
if( p->pEntry ){
*pRowid = p->pEntry->v;
p->pEntry = p->pEntry->pRight;
if( p->pEntry==0 ){
sqlite3RowSetClear(p);
}
return 1;
}else{
return 0;
}
}
/*
** Extract the next (smallest) element from the RowSet.
** Write the element into *pRowid. Return 1 on success. Return
** 0 if the RowSet is already empty.
*/
int sqlite3RowSetNext(RowSet *p, i64 *pRowid){
if( !p->isSorted ){
sqlite3RowSetSort(p);
}
if( p->pEntry ){
*pRowid = p->pEntry->v;
p->pEntry = p->pEntry->pNext;
if( p->pEntry==0 ){
sqlite3RowSetClear(p);
}
return 1;
}else{
return 0;
}
}
/*
** If the memory cell contains a string value that must be freed by
** invoking an external callback, free it now. Calling this function
** does not free any Mem.zMalloc buffer.
*/
void sqlite3VdbeMemReleaseExternal(Mem *p){
assert( p->db==0 || sqlite3_mutex_held(p->db->mutex) );
if( p->flags&(MEM_Agg|MEM_Dyn|MEM_RowSet) ){
if( p->flags&MEM_Agg ){
sqlite3VdbeMemFinalize(p, p->u.pDef);
assert( (p->flags & MEM_Agg)==0 );
sqlite3VdbeMemRelease(p);
}else if( p->flags&MEM_Dyn && p->xDel ){
assert( (p->flags&MEM_RowSet)==0 );
p->xDel((void *)p->z);
p->xDel = 0;
}else if( p->flags&MEM_RowSet ){
sqlite3RowSetClear(p->u.pRowSet);
}
}
}
/*
** If the memory cell contains a string value that must be freed by
** invoking an external callback, free it now. Calling this function
** does not free any Mem.zMalloc buffer.
*/
SQLITE_PRIVATE void sqlite3VdbeMemReleaseExternal(Mem *p){
assert( p->db==0 || sqlite3_mutex_held(p->db->mutex) );
if( p->flags&MEM_Agg ){
sqlite3VdbeMemFinalize(p, p->u.pDef);
assert( (p->flags & MEM_Agg)==0 );
sqlite3VdbeMemRelease(p);
}else if( p->flags&MEM_Dyn && p->xDel ){
assert( (p->flags&MEM_RowSet)==0 );
assert( p->xDel!=SQLITE_DYNAMIC );
p->xDel((void *)p->z);
p->xDel = 0;
}else if( p->flags&MEM_RowSet ){
sqlite3RowSetClear(p->u.pRowSet);
}else if( p->flags&MEM_Frame ){
sqlite3VdbeMemSetNull(p);
}
}
/*
** Extract the smallest element from the RowSet.
** Write the element into *pRowid. Return 1 on success. Return
** 0 if the RowSet is already empty.
**
** After this routine has been called, the sqlite3RowSetInsert()
** routine may not be called again.
*/
int sqlite3RowSetNext(RowSet *p, i64 *pRowid){
assert( p!=0 );
/* Merge the forest into a single sorted list on first call */
if( (p->rsFlags & ROWSET_NEXT)==0 ) rowSetToList(p);
/* Return the next entry on the list */
if( p->pEntry ){
*pRowid = p->pEntry->v;
p->pEntry = p->pEntry->pRight;
if( p->pEntry==0 ){
sqlite3RowSetClear(p);
}
return 1;
}else{
return 0;
}
}
/*
** Delete any previous value and set the value of pMem to be an
** empty boolean index.
*/
void sqlite3VdbeMemSetRowSet(Mem *pMem){
sqlite3 *db = pMem->db;
assert( db!=0 );
if( pMem->flags & MEM_RowSet ){
sqlite3RowSetClear(pMem->u.pRowSet);
}else{
sqlite3VdbeMemRelease(pMem);
pMem->zMalloc = sqlite3DbMallocRaw(db, 64);
}
if( db->mallocFailed ){
pMem->flags = MEM_Null;
}else{
assert( pMem->zMalloc );
pMem->u.pRowSet = sqlite3RowSetInit(db, pMem->zMalloc,
sqlite3DbMallocSize(db, pMem->zMalloc));
assert( pMem->u.pRowSet!=0 );
pMem->flags = MEM_RowSet;
}
}
