/*
* Returns true if a trigger matching op, tr_tm and foreach that is NOT already
* on the Parse objects trigger-stack (to prevent recursive trigger firing) is
* found in the list specified as pTrigger.
*/
int sqlite3TriggersExist(
Parse *pParse, /* Used to check for recursive triggers */
Trigger *pTrigger, /* A list of triggers associated with a table */
int op, /* one of TK_DELETE, TK_INSERT, TK_UPDATE */
int tr_tm, /* one of TK_BEFORE, TK_AFTER */
int foreach, /* one of TK_ROW or TK_STATEMENT */
ExprList *pChanges /* Columns that change in an UPDATE statement */
){
Trigger * pTriggerCursor;
if( sqlite3_always_code_trigger_setup ){
return 1;
}
pTriggerCursor = pTrigger;
while( pTriggerCursor ){
if( pTriggerCursor->op == op &&
pTriggerCursor->tr_tm == tr_tm &&
pTriggerCursor->foreach == foreach &&
checkColumnOverLap(pTriggerCursor->pColumns, pChanges) ){
TriggerStack * ss;
ss = pParse->trigStack;
while( ss && ss->pTrigger != pTrigger ){
ss = ss->pNext;
}
if( !ss )return 1;
}
pTriggerCursor = pTriggerCursor->pNext;
}
return 0;
}
/*
** Return a bit vector to indicate what kind of triggers exist for operation
** "op" on table pTab. If pChanges is not NULL then it is a list of columns
** that are being updated. Triggers only match if the ON clause of the
** trigger definition overlaps the set of columns being updated.
**
** The returned bit vector is some combination of TRIGGER_BEFORE and
** TRIGGER_AFTER.
*/
int sqlite3TriggersExist(
Parse *pParse, /* Used to check for recursive triggers */
Table *pTab, /* The table the contains the triggers */
int op, /* one of TK_DELETE, TK_INSERT, TK_UPDATE */
ExprList *pChanges /* Columns that change in an UPDATE statement */
){
Trigger *pTrigger = pTab->pTrigger;
int mask = 0;
while( pTrigger ){
if( pTrigger->op==op && checkColumnOverLap(pTrigger->pColumns, pChanges) ){
mask |= pTrigger->tr_tm;
}
pTrigger = pTrigger->pNext;
}
return mask;
}
/*
** This is called to code FOR EACH ROW triggers.
**
** When the code that this function generates is executed, the following
** must be true:
**
** 1. No cursors may be open in the main database. (But newIdx and oldIdx
** can be indices of cursors in temporary tables. See below.)
**
** 2. If the triggers being coded are ON INSERT or ON UPDATE triggers, then
** a temporary vdbe cursor (index newIdx) must be open and pointing at
** a row containing values to be substituted for new.* expressions in the
** trigger program(s).
**
** 3. If the triggers being coded are ON DELETE or ON UPDATE triggers, then
** a temporary vdbe cursor (index oldIdx) must be open and pointing at
** a row containing values to be substituted for old.* expressions in the
** trigger program(s).
**
*/
int sqlite3CodeRowTrigger(
Parse *pParse, /* Parse context */
int op, /* One of TK_UPDATE, TK_INSERT, TK_DELETE */
ExprList *pChanges, /* Changes list for any UPDATE OF triggers */
int tr_tm, /* One of TK_BEFORE, TK_AFTER */
Table *pTab, /* The table to code triggers from */
int newIdx, /* The indice of the "new" row to access */
int oldIdx, /* The indice of the "old" row to access */
int orconf, /* ON CONFLICT policy */
int ignoreJump /* Instruction to jump to for RAISE(IGNORE) */
){
Trigger * pTrigger;
TriggerStack * pTriggerStack;
assert(op == TK_UPDATE || op == TK_INSERT || op == TK_DELETE);
assert(tr_tm == TK_BEFORE || tr_tm == TK_AFTER );
assert(newIdx != -1 || oldIdx != -1);
pTrigger = pTab->pTrigger;
while( pTrigger ){
int fire_this = 0;
/* determine whether we should code this trigger */
if( pTrigger->op == op && pTrigger->tr_tm == tr_tm &&
pTrigger->foreach == TK_ROW ){
fire_this = 1;
pTriggerStack = pParse->trigStack;
while( pTriggerStack ){
if( pTriggerStack->pTrigger == pTrigger ){
fire_this = 0;
}
pTriggerStack = pTriggerStack->pNext;
}
if( op == TK_UPDATE && pTrigger->pColumns &&
!checkColumnOverLap(pTrigger->pColumns, pChanges) ){
fire_this = 0;
}
}
if( fire_this && (pTriggerStack = sqliteMalloc(sizeof(TriggerStack)))!=0 ){
int endTrigger;
SrcList dummyTablist;
Expr * whenExpr;
AuthContext sContext;
dummyTablist.nSrc = 0;
/* Push an entry on to the trigger stack */
pTriggerStack->pTrigger = pTrigger;
pTriggerStack->newIdx = newIdx;
pTriggerStack->oldIdx = oldIdx;
pTriggerStack->pTab = pTab;
pTriggerStack->pNext = pParse->trigStack;
pTriggerStack->ignoreJump = ignoreJump;
pParse->trigStack = pTriggerStack;
sqlite3AuthContextPush(pParse, &sContext, pTrigger->name);
/* code the WHEN clause */
endTrigger = sqlite3VdbeMakeLabel(pParse->pVdbe);
whenExpr = sqlite3ExprDup(pTrigger->pWhen);
if( sqlite3ExprResolveIds(pParse, &dummyTablist, 0, whenExpr) ){
pParse->trigStack = pParse->trigStack->pNext;
sqliteFree(pTriggerStack);
sqlite3ExprDelete(whenExpr);
return 1;
}
sqlite3ExprIfFalse(pParse, whenExpr, endTrigger, 1);
sqlite3ExprDelete(whenExpr);
sqlite3VdbeAddOp(pParse->pVdbe, OP_ContextPush, 0, 0);
codeTriggerProgram(pParse, pTrigger->step_list, orconf);
sqlite3VdbeAddOp(pParse->pVdbe, OP_ContextPop, 0, 0);
/* Pop the entry off the trigger stack */
pParse->trigStack = pParse->trigStack->pNext;
sqlite3AuthContextPop(&sContext);
sqliteFree(pTriggerStack);
sqlite3VdbeResolveLabel(pParse->pVdbe, endTrigger);
}
pTrigger = pTrigger->pNext;
}
return 0;
}
/*
** This is called to code FOR EACH ROW triggers.
**
** When the code that this function generates is executed, the following
** must be true:
**
** 1. No cursors may be open in the main database. (But newIdx and oldIdx
** can be indices of cursors in temporary tables. See below.)
**
** 2. If the triggers being coded are ON INSERT or ON UPDATE triggers, then
** a temporary vdbe cursor (index newIdx) must be open and pointing at
** a row containing values to be substituted for new.* expressions in the
** trigger program(s).
**
** 3. If the triggers being coded are ON DELETE or ON UPDATE triggers, then
** a temporary vdbe cursor (index oldIdx) must be open and pointing at
** a row containing values to be substituted for old.* expressions in the
** trigger program(s).
**
*/
int sqlite3CodeRowTrigger(
Parse *pParse, /* Parse context */
int op, /* One of TK_UPDATE, TK_INSERT, TK_DELETE */
ExprList *pChanges, /* Changes list for any UPDATE OF triggers */
int tr_tm, /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
Table *pTab, /* The table to code triggers from */
int newIdx, /* The indice of the "new" row to access */
int oldIdx, /* The indice of the "old" row to access */
int orconf, /* ON CONFLICT policy */
int ignoreJump /* Instruction to jump to for RAISE(IGNORE) */
){
Trigger *p;
TriggerStack trigStackEntry;
assert(op == TK_UPDATE || op == TK_INSERT || op == TK_DELETE);
assert(tr_tm == TRIGGER_BEFORE || tr_tm == TRIGGER_AFTER );
assert(newIdx != -1 || oldIdx != -1);
for(p=pTab->pTrigger; p; p=p->pNext){
int fire_this = 0;
sqlite3 *db = pParse->db;
/* Determine whether we should code this trigger */
if(
p->op==op &&
p->tr_tm==tr_tm &&
(p->pSchema==p->pTabSchema || p->pSchema==db->aDb[1].pSchema) &&
(op!=TK_UPDATE||!p->pColumns||checkColumnOverLap(p->pColumns,pChanges))
){
TriggerStack *pS; /* Pointer to trigger-stack entry */
for(pS=pParse->trigStack; pS && p!=pS->pTrigger; pS=pS->pNext){}
if( !pS ){
fire_this = 1;
}
#if 0 /* Give no warning for recursive triggers. Just do not do them */
else{
sqlite3ErrorMsg(pParse, "recursive triggers not supported (%s)",
p->name);
return SQLITE_ERROR;
}
#endif
}
if( fire_this ){
int endTrigger;
Expr * whenExpr;
AuthContext sContext;
NameContext sNC;
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
/* Push an entry on to the trigger stack */
trigStackEntry.pTrigger = p;
trigStackEntry.newIdx = newIdx;
trigStackEntry.oldIdx = oldIdx;
trigStackEntry.pTab = pTab;
trigStackEntry.pNext = pParse->trigStack;
trigStackEntry.ignoreJump = ignoreJump;
pParse->trigStack = &trigStackEntry;
sqlite3AuthContextPush(pParse, &sContext, p->name);
/* code the WHEN clause */
endTrigger = sqlite3VdbeMakeLabel(pParse->pVdbe);
whenExpr = sqlite3ExprDup(db, p->pWhen);
if( db->mallocFailed || sqlite3ExprResolveNames(&sNC, whenExpr) ){
pParse->trigStack = trigStackEntry.pNext;
sqlite3ExprDelete(whenExpr);
return 1;
}
sqlite3ExprIfFalse(pParse, whenExpr, endTrigger, 1);
sqlite3ExprDelete(whenExpr);
codeTriggerProgram(pParse, p->step_list, orconf);
/* Pop the entry off the trigger stack */
pParse->trigStack = trigStackEntry.pNext;
sqlite3AuthContextPop(&sContext);
sqlite3VdbeResolveLabel(pParse->pVdbe, endTrigger);
}
}
return 0;
}
/*
** This is called to code FOR EACH ROW triggers.
**
** When the code that this function generates is executed, the following
** must be true:
**
** 1. No cursors may be open in the main database. (But newIdx and oldIdx
** can be indices of cursors in temporary tables. See below.)
**
** 2. If the triggers being coded are ON INSERT or ON UPDATE triggers, then
** a temporary vdbe cursor (index newIdx) must be open and pointing at
** a row containing values to be substituted for new.* expressions in the
** trigger program(s).
**
** 3. If the triggers being coded are ON DELETE or ON UPDATE triggers, then
** a temporary vdbe cursor (index oldIdx) must be open and pointing at
** a row containing values to be substituted for old.* expressions in the
** trigger program(s).
**
*/
int sqlite3CodeRowTrigger(
Parse *pParse, /* Parse context */
int op, /* One of TK_UPDATE, TK_INSERT, TK_DELETE */
ExprList *pChanges, /* Changes list for any UPDATE OF triggers */
int tr_tm, /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
Table *pTab, /* The table to code triggers from */
int newIdx, /* The indice of the "new" row to access */
int oldIdx, /* The indice of the "old" row to access */
int orconf, /* ON CONFLICT policy */
int ignoreJump /* Instruction to jump to for RAISE(IGNORE) */
){
Trigger *pTrigger;
TriggerStack *pStack;
TriggerStack trigStackEntry;
assert(op == TK_UPDATE || op == TK_INSERT || op == TK_DELETE);
assert(tr_tm == TRIGGER_BEFORE || tr_tm == TRIGGER_AFTER );
assert(newIdx != -1 || oldIdx != -1);
pTrigger = pTab->pTrigger;
while( pTrigger ){
int fire_this = 0;
/* determine whether we should code this trigger */
if( pTrigger->op == op && pTrigger->tr_tm == tr_tm ){
fire_this = 1;
for(pStack=pParse->trigStack; pStack; pStack=pStack->pNext){
if( pStack->pTrigger==pTrigger ){
fire_this = 0;
}
}
if( op == TK_UPDATE && pTrigger->pColumns &&
!checkColumnOverLap(pTrigger->pColumns, pChanges) ){
fire_this = 0;
}
}
if( fire_this ){
int endTrigger;
Expr * whenExpr;
AuthContext sContext;
NameContext sNC;
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
/* Push an entry on to the trigger stack */
trigStackEntry.pTrigger = pTrigger;
trigStackEntry.newIdx = newIdx;
trigStackEntry.oldIdx = oldIdx;
trigStackEntry.pTab = pTab;
trigStackEntry.pNext = pParse->trigStack;
trigStackEntry.ignoreJump = ignoreJump;
pParse->trigStack = &trigStackEntry;
sqlite3AuthContextPush(pParse, &sContext, pTrigger->name);
/* code the WHEN clause */
endTrigger = sqlite3VdbeMakeLabel(pParse->pVdbe);
whenExpr = sqlite3ExprDup(pTrigger->pWhen);
if( sqlite3ExprResolveNames(&sNC, whenExpr) ){
pParse->trigStack = trigStackEntry.pNext;
sqlite3ExprDelete(whenExpr);
return 1;
}
sqlite3ExprIfFalse(pParse, whenExpr, endTrigger, 1);
sqlite3ExprDelete(whenExpr);
codeTriggerProgram(pParse, pTrigger->step_list, orconf);
/* Pop the entry off the trigger stack */
pParse->trigStack = trigStackEntry.pNext;
sqlite3AuthContextPop(&sContext);
sqlite3VdbeResolveLabel(pParse->pVdbe, endTrigger);
}
pTrigger = pTrigger->pNext;
}
return 0;
}
