/*
** 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).
**
** If they are not NULL, the piOldColMask and piNewColMask output variables
** are set to values that describe the columns used by the trigger program
** in the OLD.* and NEW.* tables respectively. If column N of the
** pseudo-table is read at least once, the corresponding bit of the output
** mask is set. If a column with an index greater than 32 is read, the
** output mask is set to the special value 0xffffffff.
**
*/
static int sqlite3CodeRowTrigger(
Parse pParse, /* Parse context */
Trigger pTrigger, /* List of triggers on table pTab */
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) */
ref u32 piOldColMask, /* OUT: Mask of columns used from the OLD.* table */
ref u32 piNewColMask /* OUT: Mask of columns used from the NEW.* table */
)
{
Trigger p;
sqlite3 db = pParse.db;
TriggerStack trigStackEntry = new TriggerStack();
trigStackEntry.oldColMask = 0;
trigStackEntry.newColMask = 0;
Debug.Assert(op == TK_UPDATE || op == TK_INSERT || op == TK_DELETE);
Debug.Assert(tr_tm == TRIGGER_BEFORE || tr_tm == TRIGGER_AFTER);
Debug.Assert(newIdx != -1 || oldIdx != -1);
for (p = pTrigger; p != null; p = p.pNext)
{
bool fire_this = false;
/* Sanity checking: The schema for the trigger and for the table are
** always defined. The trigger must be in the same schema as the table
** or else it must be a TEMP trigger. */
Debug.Assert(p.pSchema != null);
Debug.Assert(p.pTabSchema != null);
Debug.Assert(p.pSchema == p.pTabSchema || p.pSchema == db.aDb[1].pSchema);
/* Determine whether we should code this trigger */
if (
p.op == op &&
p.tr_tm == tr_tm &&
checkColumnOverlap(p.pColumns, pChanges) != 0)
{
TriggerStack pS; /* Pointer to trigger-stack entry */
for (pS = pParse.trigStack; pS != null && p != pS.pTrigger; pS = pS.pNext)
{
}
if (pS == null)
{
fire_this = true;
}
#if FALSE // * 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;
#if !SQLITE_OMIT_TRACE
sqlite3VdbeAddOp4(pParse.pVdbe, OP_Trace, 0, 0, 0,
sqlite3MPrintf(db, "-- TRIGGER %s", p.name),
P4_DYNAMIC);
#endif
sNC = new NameContext();// 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;
#if !SQLITE_OMIT_AUTHORIZATION
sqlite3AuthContextPush(pParse, sContext, p.name);
#endif
/* code the WHEN clause */
endTrigger = sqlite3VdbeMakeLabel(pParse.pVdbe);
whenExpr = sqlite3ExprDup(db, p.pWhen, 0);
if (/* db.mallocFailed != 0 || */ sqlite3ResolveExprNames(sNC, ref whenExpr) != 0)
{
pParse.trigStack = trigStackEntry.pNext;
sqlite3ExprDelete(db, ref whenExpr);
return(1);
}
sqlite3ExprIfFalse(pParse, whenExpr, endTrigger, SQLITE_JUMPIFNULL);
sqlite3ExprDelete(db, ref whenExpr);
codeTriggerProgram(pParse, p.step_list, orconf);
/* Pop the entry off the trigger stack */
pParse.trigStack = trigStackEntry.pNext;
#if !SQLITE_OMIT_AUTHORIZATION
sqlite3AuthContextPop(sContext);
#endif
sqlite3VdbeResolveLabel(pParse.pVdbe, endTrigger);
}
}
piOldColMask |= trigStackEntry.oldColMask; // if ( piOldColMask != 0 ) piOldColMask |= trigStackEntry.oldColMask;
piNewColMask |= trigStackEntry.newColMask; // if ( piNewColMask != 0 ) piNewColMask |= trigStackEntry.newColMask;
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).
**
** If they are not NULL, the piOldColMask and piNewColMask output variables
** are set to values that describe the columns used by the trigger program
** in the OLD.* and NEW.* tables respectively. If column N of the
** pseudo-table is read at least once, the corresponding bit of the output
** mask is set. If a column with an index greater than 32 is read, the
** output mask is set to the special value 0xffffffff.
**
*/
static int sqlite3CodeRowTrigger(
Parse pParse, /* Parse context */
Trigger pTrigger, /* List of triggers on table pTab */
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) */
ref u32 piOldColMask,/* OUT: Mask of columns used from the OLD.* table */
ref u32 piNewColMask /* OUT: Mask of columns used from the NEW.* table */
)
{
Trigger p;
sqlite3 db = pParse.db;
TriggerStack trigStackEntry = new TriggerStack();
trigStackEntry.oldColMask = 0;
trigStackEntry.newColMask = 0;
Debug.Assert( op == TK_UPDATE || op == TK_INSERT || op == TK_DELETE );
Debug.Assert( tr_tm == TRIGGER_BEFORE || tr_tm == TRIGGER_AFTER );
Debug.Assert( newIdx != -1 || oldIdx != -1 );
for ( p = pTrigger ; p != null ; p = p.pNext )
{
bool fire_this = false;
/* Sanity checking: The schema for the trigger and for the table are
** always defined. The trigger must be in the same schema as the table
** or else it must be a TEMP trigger. */
Debug.Assert( p.pSchema != null );
Debug.Assert( p.pTabSchema != null );
Debug.Assert( p.pSchema == p.pTabSchema || p.pSchema == db.aDb[1].pSchema );
/* Determine whether we should code this trigger */
if (
p.op == op &&
p.tr_tm == tr_tm &&
checkColumnOverlap( p.pColumns, pChanges ) != 0 )
{
TriggerStack pS; /* Pointer to trigger-stack entry */
for ( pS = pParse.trigStack ; pS != null && p != pS.pTrigger ; pS = pS.pNext ) { }
if ( pS == null )
{
fire_this = true;
}
#if FALSE // * 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;
#if !SQLITE_OMIT_TRACE
sqlite3VdbeAddOp4( pParse.pVdbe, OP_Trace, 0, 0, 0,
sqlite3MPrintf( db, "-- TRIGGER %s", p.name ),
P4_DYNAMIC );
#endif
sNC = new NameContext();// 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;
#if !SQLITE_OMIT_AUTHORIZATION
sqlite3AuthContextPush( pParse, sContext, p.name );
#endif
/* code the WHEN clause */
endTrigger = sqlite3VdbeMakeLabel( pParse.pVdbe );
whenExpr = sqlite3ExprDup( db, p.pWhen, 0 );
if ( /* db.mallocFailed != 0 || */ sqlite3ResolveExprNames( sNC, ref whenExpr ) != 0 )
{
pParse.trigStack = trigStackEntry.pNext;
sqlite3ExprDelete( db, ref whenExpr );
return 1;
}
sqlite3ExprIfFalse( pParse, whenExpr, endTrigger, SQLITE_JUMPIFNULL );
sqlite3ExprDelete( db, ref whenExpr );
codeTriggerProgram( pParse, p.step_list, orconf );
/* Pop the entry off the trigger stack */
pParse.trigStack = trigStackEntry.pNext;
#if !SQLITE_OMIT_AUTHORIZATION
sqlite3AuthContextPop( sContext );
#endif
sqlite3VdbeResolveLabel( pParse.pVdbe, endTrigger );
}
}
piOldColMask |= trigStackEntry.oldColMask; // if ( piOldColMask != 0 ) piOldColMask |= trigStackEntry.oldColMask;
piNewColMask |= trigStackEntry.newColMask; // if ( piNewColMask != 0 ) piNewColMask |= trigStackEntry.newColMask;
return 0;
}
