| Index: third_party/sqlite/src/src/trigger.c
|
| diff --git a/third_party/sqlite/src/src/trigger.c b/third_party/sqlite/src/src/trigger.c
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..0f3f5bad394e35819f77733acc26d1533f844109
|
| --- /dev/null
|
| +++ b/third_party/sqlite/src/src/trigger.c
|
| @@ -0,0 +1,1111 @@
|
| +/*
|
| +**
|
| +** The author disclaims copyright to this source code. In place of
|
| +** a legal notice, here is a blessing:
|
| +**
|
| +** May you do good and not evil.
|
| +** May you find forgiveness for yourself and forgive others.
|
| +** May you share freely, never taking more than you give.
|
| +**
|
| +*************************************************************************
|
| +** This file contains the implementation for TRIGGERs
|
| +*/
|
| +#include "sqliteInt.h"
|
| +
|
| +#ifndef SQLITE_OMIT_TRIGGER
|
| +/*
|
| +** Delete a linked list of TriggerStep structures.
|
| +*/
|
| +void sqlite3DeleteTriggerStep(sqlite3 *db, TriggerStep *pTriggerStep){
|
| + while( pTriggerStep ){
|
| + TriggerStep * pTmp = pTriggerStep;
|
| + pTriggerStep = pTriggerStep->pNext;
|
| +
|
| + sqlite3ExprDelete(db, pTmp->pWhere);
|
| + sqlite3ExprListDelete(db, pTmp->pExprList);
|
| + sqlite3SelectDelete(db, pTmp->pSelect);
|
| + sqlite3IdListDelete(db, pTmp->pIdList);
|
| +
|
| + sqlite3DbFree(db, pTmp);
|
| + }
|
| +}
|
| +
|
| +/*
|
| +** Given table pTab, return a list of all the triggers attached to
|
| +** the table. The list is connected by Trigger.pNext pointers.
|
| +**
|
| +** All of the triggers on pTab that are in the same database as pTab
|
| +** are already attached to pTab->pTrigger. But there might be additional
|
| +** triggers on pTab in the TEMP schema. This routine prepends all
|
| +** TEMP triggers on pTab to the beginning of the pTab->pTrigger list
|
| +** and returns the combined list.
|
| +**
|
| +** To state it another way: This routine returns a list of all triggers
|
| +** that fire off of pTab. The list will include any TEMP triggers on
|
| +** pTab as well as the triggers lised in pTab->pTrigger.
|
| +*/
|
| +Trigger *sqlite3TriggerList(Parse *pParse, Table *pTab){
|
| + Schema * const pTmpSchema = pParse->db->aDb[1].pSchema;
|
| + Trigger *pList = 0; /* List of triggers to return */
|
| +
|
| + if( pParse->disableTriggers ){
|
| + return 0;
|
| + }
|
| +
|
| + if( pTmpSchema!=pTab->pSchema ){
|
| + HashElem *p;
|
| + assert( sqlite3SchemaMutexHeld(pParse->db, 0, pTmpSchema) );
|
| + for(p=sqliteHashFirst(&pTmpSchema->trigHash); p; p=sqliteHashNext(p)){
|
| + Trigger *pTrig = (Trigger *)sqliteHashData(p);
|
| + if( pTrig->pTabSchema==pTab->pSchema
|
| + && 0==sqlite3StrICmp(pTrig->table, pTab->zName)
|
| + ){
|
| + pTrig->pNext = (pList ? pList : pTab->pTrigger);
|
| + pList = pTrig;
|
| + }
|
| + }
|
| + }
|
| +
|
| + return (pList ? pList : pTab->pTrigger);
|
| +}
|
| +
|
| +/*
|
| +** This is called by the parser when it sees a CREATE TRIGGER statement
|
| +** up to the point of the BEGIN before the trigger actions. A Trigger
|
| +** structure is generated based on the information available and stored
|
| +** in pParse->pNewTrigger. After the trigger actions have been parsed, the
|
| +** sqlite3FinishTrigger() function is called to complete the trigger
|
| +** construction process.
|
| +*/
|
| +void sqlite3BeginTrigger(
|
| + Parse *pParse, /* The parse context of the CREATE TRIGGER statement */
|
| + Token *pName1, /* The name of the trigger */
|
| + Token *pName2, /* The name of the trigger */
|
| + int tr_tm, /* One of TK_BEFORE, TK_AFTER, TK_INSTEAD */
|
| + int op, /* One of TK_INSERT, TK_UPDATE, TK_DELETE */
|
| + IdList *pColumns, /* column list if this is an UPDATE OF trigger */
|
| + SrcList *pTableName,/* The name of the table/view the trigger applies to */
|
| + Expr *pWhen, /* WHEN clause */
|
| + int isTemp, /* True if the TEMPORARY keyword is present */
|
| + int noErr /* Suppress errors if the trigger already exists */
|
| +){
|
| + Trigger *pTrigger = 0; /* The new trigger */
|
| + Table *pTab; /* Table that the trigger fires off of */
|
| + char *zName = 0; /* Name of the trigger */
|
| + sqlite3 *db = pParse->db; /* The database connection */
|
| + int iDb; /* The database to store the trigger in */
|
| + Token *pName; /* The unqualified db name */
|
| + DbFixer sFix; /* State vector for the DB fixer */
|
| + int iTabDb; /* Index of the database holding pTab */
|
| +
|
| + assert( pName1!=0 ); /* pName1->z might be NULL, but not pName1 itself */
|
| + assert( pName2!=0 );
|
| + assert( op==TK_INSERT || op==TK_UPDATE || op==TK_DELETE );
|
| + assert( op>0 && op<0xff );
|
| + if( isTemp ){
|
| + /* If TEMP was specified, then the trigger name may not be qualified. */
|
| + if( pName2->n>0 ){
|
| + sqlite3ErrorMsg(pParse, "temporary trigger may not have qualified name");
|
| + goto trigger_cleanup;
|
| + }
|
| + iDb = 1;
|
| + pName = pName1;
|
| + }else{
|
| + /* Figure out the db that the the trigger will be created in */
|
| + iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pName);
|
| + if( iDb<0 ){
|
| + goto trigger_cleanup;
|
| + }
|
| + }
|
| +
|
| + /* If the trigger name was unqualified, and the table is a temp table,
|
| + ** then set iDb to 1 to create the trigger in the temporary database.
|
| + ** If sqlite3SrcListLookup() returns 0, indicating the table does not
|
| + ** exist, the error is caught by the block below.
|
| + */
|
| + if( !pTableName || db->mallocFailed ){
|
| + goto trigger_cleanup;
|
| + }
|
| + pTab = sqlite3SrcListLookup(pParse, pTableName);
|
| + if( db->init.busy==0 && pName2->n==0 && pTab
|
| + && pTab->pSchema==db->aDb[1].pSchema ){
|
| + iDb = 1;
|
| + }
|
| +
|
| + /* Ensure the table name matches database name and that the table exists */
|
| + if( db->mallocFailed ) goto trigger_cleanup;
|
| + assert( pTableName->nSrc==1 );
|
| + if( sqlite3FixInit(&sFix, pParse, iDb, "trigger", pName) &&
|
| + sqlite3FixSrcList(&sFix, pTableName) ){
|
| + goto trigger_cleanup;
|
| + }
|
| + pTab = sqlite3SrcListLookup(pParse, pTableName);
|
| + if( !pTab ){
|
| + /* The table does not exist. */
|
| + if( db->init.iDb==1 ){
|
| + /* Ticket #3810.
|
| + ** Normally, whenever a table is dropped, all associated triggers are
|
| + ** dropped too. But if a TEMP trigger is created on a non-TEMP table
|
| + ** and the table is dropped by a different database connection, the
|
| + ** trigger is not visible to the database connection that does the
|
| + ** drop so the trigger cannot be dropped. This results in an
|
| + ** "orphaned trigger" - a trigger whose associated table is missing.
|
| + */
|
| + db->init.orphanTrigger = 1;
|
| + }
|
| + goto trigger_cleanup;
|
| + }
|
| + if( IsVirtual(pTab) ){
|
| + sqlite3ErrorMsg(pParse, "cannot create triggers on virtual tables");
|
| + goto trigger_cleanup;
|
| + }
|
| +
|
| + /* Check that the trigger name is not reserved and that no trigger of the
|
| + ** specified name exists */
|
| + zName = sqlite3NameFromToken(db, pName);
|
| + if( !zName || SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
|
| + goto trigger_cleanup;
|
| + }
|
| + assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
|
| + if( sqlite3HashFind(&(db->aDb[iDb].pSchema->trigHash),
|
| + zName, sqlite3Strlen30(zName)) ){
|
| + if( !noErr ){
|
| + sqlite3ErrorMsg(pParse, "trigger %T already exists", pName);
|
| + }else{
|
| + assert( !db->init.busy );
|
| + sqlite3CodeVerifySchema(pParse, iDb);
|
| + }
|
| + goto trigger_cleanup;
|
| + }
|
| +
|
| + /* Do not create a trigger on a system table */
|
| + if( sqlite3StrNICmp(pTab->zName, "sqlite_", 7)==0 ){
|
| + sqlite3ErrorMsg(pParse, "cannot create trigger on system table");
|
| + pParse->nErr++;
|
| + goto trigger_cleanup;
|
| + }
|
| +
|
| + /* INSTEAD of triggers are only for views and views only support INSTEAD
|
| + ** of triggers.
|
| + */
|
| + if( pTab->pSelect && tr_tm!=TK_INSTEAD ){
|
| + sqlite3ErrorMsg(pParse, "cannot create %s trigger on view: %S",
|
| + (tr_tm == TK_BEFORE)?"BEFORE":"AFTER", pTableName, 0);
|
| + goto trigger_cleanup;
|
| + }
|
| + if( !pTab->pSelect && tr_tm==TK_INSTEAD ){
|
| + sqlite3ErrorMsg(pParse, "cannot create INSTEAD OF"
|
| + " trigger on table: %S", pTableName, 0);
|
| + goto trigger_cleanup;
|
| + }
|
| + iTabDb = sqlite3SchemaToIndex(db, pTab->pSchema);
|
| +
|
| +#ifndef SQLITE_OMIT_AUTHORIZATION
|
| + {
|
| + int code = SQLITE_CREATE_TRIGGER;
|
| + const char *zDb = db->aDb[iTabDb].zName;
|
| + const char *zDbTrig = isTemp ? db->aDb[1].zName : zDb;
|
| + if( iTabDb==1 || isTemp ) code = SQLITE_CREATE_TEMP_TRIGGER;
|
| + if( sqlite3AuthCheck(pParse, code, zName, pTab->zName, zDbTrig) ){
|
| + goto trigger_cleanup;
|
| + }
|
| + if( sqlite3AuthCheck(pParse, SQLITE_INSERT, SCHEMA_TABLE(iTabDb),0,zDb)){
|
| + goto trigger_cleanup;
|
| + }
|
| + }
|
| +#endif
|
| +
|
| + /* INSTEAD OF triggers can only appear on views and BEFORE triggers
|
| + ** cannot appear on views. So we might as well translate every
|
| + ** INSTEAD OF trigger into a BEFORE trigger. It simplifies code
|
| + ** elsewhere.
|
| + */
|
| + if (tr_tm == TK_INSTEAD){
|
| + tr_tm = TK_BEFORE;
|
| + }
|
| +
|
| + /* Build the Trigger object */
|
| + pTrigger = (Trigger*)sqlite3DbMallocZero(db, sizeof(Trigger));
|
| + if( pTrigger==0 ) goto trigger_cleanup;
|
| + pTrigger->zName = zName;
|
| + zName = 0;
|
| + pTrigger->table = sqlite3DbStrDup(db, pTableName->a[0].zName);
|
| + pTrigger->pSchema = db->aDb[iDb].pSchema;
|
| + pTrigger->pTabSchema = pTab->pSchema;
|
| + pTrigger->op = (u8)op;
|
| + pTrigger->tr_tm = tr_tm==TK_BEFORE ? TRIGGER_BEFORE : TRIGGER_AFTER;
|
| + pTrigger->pWhen = sqlite3ExprDup(db, pWhen, EXPRDUP_REDUCE);
|
| + pTrigger->pColumns = sqlite3IdListDup(db, pColumns);
|
| + assert( pParse->pNewTrigger==0 );
|
| + pParse->pNewTrigger = pTrigger;
|
| +
|
| +trigger_cleanup:
|
| + sqlite3DbFree(db, zName);
|
| + sqlite3SrcListDelete(db, pTableName);
|
| + sqlite3IdListDelete(db, pColumns);
|
| + sqlite3ExprDelete(db, pWhen);
|
| + if( !pParse->pNewTrigger ){
|
| + sqlite3DeleteTrigger(db, pTrigger);
|
| + }else{
|
| + assert( pParse->pNewTrigger==pTrigger );
|
| + }
|
| +}
|
| +
|
| +/*
|
| +** This routine is called after all of the trigger actions have been parsed
|
| +** in order to complete the process of building the trigger.
|
| +*/
|
| +void sqlite3FinishTrigger(
|
| + Parse *pParse, /* Parser context */
|
| + TriggerStep *pStepList, /* The triggered program */
|
| + Token *pAll /* Token that describes the complete CREATE TRIGGER */
|
| +){
|
| + Trigger *pTrig = pParse->pNewTrigger; /* Trigger being finished */
|
| + char *zName; /* Name of trigger */
|
| + sqlite3 *db = pParse->db; /* The database */
|
| + DbFixer sFix; /* Fixer object */
|
| + int iDb; /* Database containing the trigger */
|
| + Token nameToken; /* Trigger name for error reporting */
|
| +
|
| + pParse->pNewTrigger = 0;
|
| + if( NEVER(pParse->nErr) || !pTrig ) goto triggerfinish_cleanup;
|
| + zName = pTrig->zName;
|
| + iDb = sqlite3SchemaToIndex(pParse->db, pTrig->pSchema);
|
| + pTrig->step_list = pStepList;
|
| + while( pStepList ){
|
| + pStepList->pTrig = pTrig;
|
| + pStepList = pStepList->pNext;
|
| + }
|
| + nameToken.z = pTrig->zName;
|
| + nameToken.n = sqlite3Strlen30(nameToken.z);
|
| + if( sqlite3FixInit(&sFix, pParse, iDb, "trigger", &nameToken)
|
| + && sqlite3FixTriggerStep(&sFix, pTrig->step_list) ){
|
| + goto triggerfinish_cleanup;
|
| + }
|
| +
|
| + /* if we are not initializing,
|
| + ** build the sqlite_master entry
|
| + */
|
| + if( !db->init.busy ){
|
| + Vdbe *v;
|
| + char *z;
|
| +
|
| + /* Make an entry in the sqlite_master table */
|
| + v = sqlite3GetVdbe(pParse);
|
| + if( v==0 ) goto triggerfinish_cleanup;
|
| + sqlite3BeginWriteOperation(pParse, 0, iDb);
|
| + z = sqlite3DbStrNDup(db, (char*)pAll->z, pAll->n);
|
| + sqlite3NestedParse(pParse,
|
| + "INSERT INTO %Q.%s VALUES('trigger',%Q,%Q,0,'CREATE TRIGGER %q')",
|
| + db->aDb[iDb].zName, SCHEMA_TABLE(iDb), zName,
|
| + pTrig->table, z);
|
| + sqlite3DbFree(db, z);
|
| + sqlite3ChangeCookie(pParse, iDb);
|
| + sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 0, 0, sqlite3MPrintf(
|
| + db, "type='trigger' AND name='%q'", zName), P4_DYNAMIC
|
| + );
|
| + }
|
| +
|
| + if( db->init.busy ){
|
| + Trigger *pLink = pTrig;
|
| + Hash *pHash = &db->aDb[iDb].pSchema->trigHash;
|
| + assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
|
| + pTrig = sqlite3HashInsert(pHash, zName, sqlite3Strlen30(zName), pTrig);
|
| + if( pTrig ){
|
| + db->mallocFailed = 1;
|
| + }else if( pLink->pSchema==pLink->pTabSchema ){
|
| + Table *pTab;
|
| + int n = sqlite3Strlen30(pLink->table);
|
| + pTab = sqlite3HashFind(&pLink->pTabSchema->tblHash, pLink->table, n);
|
| + assert( pTab!=0 );
|
| + pLink->pNext = pTab->pTrigger;
|
| + pTab->pTrigger = pLink;
|
| + }
|
| + }
|
| +
|
| +triggerfinish_cleanup:
|
| + sqlite3DeleteTrigger(db, pTrig);
|
| + assert( !pParse->pNewTrigger );
|
| + sqlite3DeleteTriggerStep(db, pStepList);
|
| +}
|
| +
|
| +/*
|
| +** Turn a SELECT statement (that the pSelect parameter points to) into
|
| +** a trigger step. Return a pointer to a TriggerStep structure.
|
| +**
|
| +** The parser calls this routine when it finds a SELECT statement in
|
| +** body of a TRIGGER.
|
| +*/
|
| +TriggerStep *sqlite3TriggerSelectStep(sqlite3 *db, Select *pSelect){
|
| + TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
|
| + if( pTriggerStep==0 ) {
|
| + sqlite3SelectDelete(db, pSelect);
|
| + return 0;
|
| + }
|
| + pTriggerStep->op = TK_SELECT;
|
| + pTriggerStep->pSelect = pSelect;
|
| + pTriggerStep->orconf = OE_Default;
|
| + return pTriggerStep;
|
| +}
|
| +
|
| +/*
|
| +** Allocate space to hold a new trigger step. The allocated space
|
| +** holds both the TriggerStep object and the TriggerStep.target.z string.
|
| +**
|
| +** If an OOM error occurs, NULL is returned and db->mallocFailed is set.
|
| +*/
|
| +static TriggerStep *triggerStepAllocate(
|
| + sqlite3 *db, /* Database connection */
|
| + u8 op, /* Trigger opcode */
|
| + Token *pName /* The target name */
|
| +){
|
| + TriggerStep *pTriggerStep;
|
| +
|
| + pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep) + pName->n);
|
| + if( pTriggerStep ){
|
| + char *z = (char*)&pTriggerStep[1];
|
| + memcpy(z, pName->z, pName->n);
|
| + pTriggerStep->target.z = z;
|
| + pTriggerStep->target.n = pName->n;
|
| + pTriggerStep->op = op;
|
| + }
|
| + return pTriggerStep;
|
| +}
|
| +
|
| +/*
|
| +** Build a trigger step out of an INSERT statement. Return a pointer
|
| +** to the new trigger step.
|
| +**
|
| +** The parser calls this routine when it sees an INSERT inside the
|
| +** body of a trigger.
|
| +*/
|
| +TriggerStep *sqlite3TriggerInsertStep(
|
| + sqlite3 *db, /* The database connection */
|
| + Token *pTableName, /* Name of the table into which we insert */
|
| + IdList *pColumn, /* List of columns in pTableName to insert into */
|
| + ExprList *pEList, /* The VALUE clause: a list of values to be inserted */
|
| + Select *pSelect, /* A SELECT statement that supplies values */
|
| + u8 orconf /* The conflict algorithm (OE_Abort, OE_Replace, etc.) */
|
| +){
|
| + TriggerStep *pTriggerStep;
|
| +
|
| + assert(pEList == 0 || pSelect == 0);
|
| + assert(pEList != 0 || pSelect != 0 || db->mallocFailed);
|
| +
|
| + pTriggerStep = triggerStepAllocate(db, TK_INSERT, pTableName);
|
| + if( pTriggerStep ){
|
| + pTriggerStep->pSelect = sqlite3SelectDup(db, pSelect, EXPRDUP_REDUCE);
|
| + pTriggerStep->pIdList = pColumn;
|
| + pTriggerStep->pExprList = sqlite3ExprListDup(db, pEList, EXPRDUP_REDUCE);
|
| + pTriggerStep->orconf = orconf;
|
| + }else{
|
| + sqlite3IdListDelete(db, pColumn);
|
| + }
|
| + sqlite3ExprListDelete(db, pEList);
|
| + sqlite3SelectDelete(db, pSelect);
|
| +
|
| + return pTriggerStep;
|
| +}
|
| +
|
| +/*
|
| +** Construct a trigger step that implements an UPDATE statement and return
|
| +** a pointer to that trigger step. The parser calls this routine when it
|
| +** sees an UPDATE statement inside the body of a CREATE TRIGGER.
|
| +*/
|
| +TriggerStep *sqlite3TriggerUpdateStep(
|
| + sqlite3 *db, /* The database connection */
|
| + Token *pTableName, /* Name of the table to be updated */
|
| + ExprList *pEList, /* The SET clause: list of column and new values */
|
| + Expr *pWhere, /* The WHERE clause */
|
| + u8 orconf /* The conflict algorithm. (OE_Abort, OE_Ignore, etc) */
|
| +){
|
| + TriggerStep *pTriggerStep;
|
| +
|
| + pTriggerStep = triggerStepAllocate(db, TK_UPDATE, pTableName);
|
| + if( pTriggerStep ){
|
| + pTriggerStep->pExprList = sqlite3ExprListDup(db, pEList, EXPRDUP_REDUCE);
|
| + pTriggerStep->pWhere = sqlite3ExprDup(db, pWhere, EXPRDUP_REDUCE);
|
| + pTriggerStep->orconf = orconf;
|
| + }
|
| + sqlite3ExprListDelete(db, pEList);
|
| + sqlite3ExprDelete(db, pWhere);
|
| + return pTriggerStep;
|
| +}
|
| +
|
| +/*
|
| +** Construct a trigger step that implements a DELETE statement and return
|
| +** a pointer to that trigger step. The parser calls this routine when it
|
| +** sees a DELETE statement inside the body of a CREATE TRIGGER.
|
| +*/
|
| +TriggerStep *sqlite3TriggerDeleteStep(
|
| + sqlite3 *db, /* Database connection */
|
| + Token *pTableName, /* The table from which rows are deleted */
|
| + Expr *pWhere /* The WHERE clause */
|
| +){
|
| + TriggerStep *pTriggerStep;
|
| +
|
| + pTriggerStep = triggerStepAllocate(db, TK_DELETE, pTableName);
|
| + if( pTriggerStep ){
|
| + pTriggerStep->pWhere = sqlite3ExprDup(db, pWhere, EXPRDUP_REDUCE);
|
| + pTriggerStep->orconf = OE_Default;
|
| + }
|
| + sqlite3ExprDelete(db, pWhere);
|
| + return pTriggerStep;
|
| +}
|
| +
|
| +/*
|
| +** Recursively delete a Trigger structure
|
| +*/
|
| +void sqlite3DeleteTrigger(sqlite3 *db, Trigger *pTrigger){
|
| + if( pTrigger==0 ) return;
|
| + sqlite3DeleteTriggerStep(db, pTrigger->step_list);
|
| + sqlite3DbFree(db, pTrigger->zName);
|
| + sqlite3DbFree(db, pTrigger->table);
|
| + sqlite3ExprDelete(db, pTrigger->pWhen);
|
| + sqlite3IdListDelete(db, pTrigger->pColumns);
|
| + sqlite3DbFree(db, pTrigger);
|
| +}
|
| +
|
| +/*
|
| +** This function is called to drop a trigger from the database schema.
|
| +**
|
| +** This may be called directly from the parser and therefore identifies
|
| +** the trigger by name. The sqlite3DropTriggerPtr() routine does the
|
| +** same job as this routine except it takes a pointer to the trigger
|
| +** instead of the trigger name.
|
| +**/
|
| +void sqlite3DropTrigger(Parse *pParse, SrcList *pName, int noErr){
|
| + Trigger *pTrigger = 0;
|
| + int i;
|
| + const char *zDb;
|
| + const char *zName;
|
| + int nName;
|
| + sqlite3 *db = pParse->db;
|
| +
|
| + if( db->mallocFailed ) goto drop_trigger_cleanup;
|
| + if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
|
| + goto drop_trigger_cleanup;
|
| + }
|
| +
|
| + assert( pName->nSrc==1 );
|
| + zDb = pName->a[0].zDatabase;
|
| + zName = pName->a[0].zName;
|
| + nName = sqlite3Strlen30(zName);
|
| + assert( zDb!=0 || sqlite3BtreeHoldsAllMutexes(db) );
|
| + for(i=OMIT_TEMPDB; i<db->nDb; i++){
|
| + int j = (i<2) ? i^1 : i; /* Search TEMP before MAIN */
|
| + if( zDb && sqlite3StrICmp(db->aDb[j].zName, zDb) ) continue;
|
| + assert( sqlite3SchemaMutexHeld(db, j, 0) );
|
| + pTrigger = sqlite3HashFind(&(db->aDb[j].pSchema->trigHash), zName, nName);
|
| + if( pTrigger ) break;
|
| + }
|
| + if( !pTrigger ){
|
| + if( !noErr ){
|
| + sqlite3ErrorMsg(pParse, "no such trigger: %S", pName, 0);
|
| + }else{
|
| + sqlite3CodeVerifyNamedSchema(pParse, zDb);
|
| + }
|
| + pParse->checkSchema = 1;
|
| + goto drop_trigger_cleanup;
|
| + }
|
| + sqlite3DropTriggerPtr(pParse, pTrigger);
|
| +
|
| +drop_trigger_cleanup:
|
| + sqlite3SrcListDelete(db, pName);
|
| +}
|
| +
|
| +/*
|
| +** Return a pointer to the Table structure for the table that a trigger
|
| +** is set on.
|
| +*/
|
| +static Table *tableOfTrigger(Trigger *pTrigger){
|
| + int n = sqlite3Strlen30(pTrigger->table);
|
| + return sqlite3HashFind(&pTrigger->pTabSchema->tblHash, pTrigger->table, n);
|
| +}
|
| +
|
| +
|
| +/*
|
| +** Drop a trigger given a pointer to that trigger.
|
| +*/
|
| +void sqlite3DropTriggerPtr(Parse *pParse, Trigger *pTrigger){
|
| + Table *pTable;
|
| + Vdbe *v;
|
| + sqlite3 *db = pParse->db;
|
| + int iDb;
|
| +
|
| + iDb = sqlite3SchemaToIndex(pParse->db, pTrigger->pSchema);
|
| + assert( iDb>=0 && iDb<db->nDb );
|
| + pTable = tableOfTrigger(pTrigger);
|
| + assert( pTable );
|
| + assert( pTable->pSchema==pTrigger->pSchema || iDb==1 );
|
| +#ifndef SQLITE_OMIT_AUTHORIZATION
|
| + {
|
| + int code = SQLITE_DROP_TRIGGER;
|
| + const char *zDb = db->aDb[iDb].zName;
|
| + const char *zTab = SCHEMA_TABLE(iDb);
|
| + if( iDb==1 ) code = SQLITE_DROP_TEMP_TRIGGER;
|
| + if( sqlite3AuthCheck(pParse, code, pTrigger->zName, pTable->zName, zDb) ||
|
| + sqlite3AuthCheck(pParse, SQLITE_DELETE, zTab, 0, zDb) ){
|
| + return;
|
| + }
|
| + }
|
| +#endif
|
| +
|
| + /* Generate code to destroy the database record of the trigger.
|
| + */
|
| + assert( pTable!=0 );
|
| + if( (v = sqlite3GetVdbe(pParse))!=0 ){
|
| + int base;
|
| + static const VdbeOpList dropTrigger[] = {
|
| + { OP_Rewind, 0, ADDR(9), 0},
|
| + { OP_String8, 0, 1, 0}, /* 1 */
|
| + { OP_Column, 0, 1, 2},
|
| + { OP_Ne, 2, ADDR(8), 1},
|
| + { OP_String8, 0, 1, 0}, /* 4: "trigger" */
|
| + { OP_Column, 0, 0, 2},
|
| + { OP_Ne, 2, ADDR(8), 1},
|
| + { OP_Delete, 0, 0, 0},
|
| + { OP_Next, 0, ADDR(1), 0}, /* 8 */
|
| + };
|
| +
|
| + sqlite3BeginWriteOperation(pParse, 0, iDb);
|
| + sqlite3OpenMasterTable(pParse, iDb);
|
| + base = sqlite3VdbeAddOpList(v, ArraySize(dropTrigger), dropTrigger);
|
| + sqlite3VdbeChangeP4(v, base+1, pTrigger->zName, P4_TRANSIENT);
|
| + sqlite3VdbeChangeP4(v, base+4, "trigger", P4_STATIC);
|
| + sqlite3ChangeCookie(pParse, iDb);
|
| + sqlite3VdbeAddOp2(v, OP_Close, 0, 0);
|
| + sqlite3VdbeAddOp4(v, OP_DropTrigger, iDb, 0, 0, pTrigger->zName, 0);
|
| + if( pParse->nMem<3 ){
|
| + pParse->nMem = 3;
|
| + }
|
| + }
|
| +}
|
| +
|
| +/*
|
| +** Remove a trigger from the hash tables of the sqlite* pointer.
|
| +*/
|
| +void sqlite3UnlinkAndDeleteTrigger(sqlite3 *db, int iDb, const char *zName){
|
| + Trigger *pTrigger;
|
| + Hash *pHash;
|
| +
|
| + assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
|
| + pHash = &(db->aDb[iDb].pSchema->trigHash);
|
| + pTrigger = sqlite3HashInsert(pHash, zName, sqlite3Strlen30(zName), 0);
|
| + if( ALWAYS(pTrigger) ){
|
| + if( pTrigger->pSchema==pTrigger->pTabSchema ){
|
| + Table *pTab = tableOfTrigger(pTrigger);
|
| + Trigger **pp;
|
| + for(pp=&pTab->pTrigger; *pp!=pTrigger; pp=&((*pp)->pNext));
|
| + *pp = (*pp)->pNext;
|
| + }
|
| + sqlite3DeleteTrigger(db, pTrigger);
|
| + db->flags |= SQLITE_InternChanges;
|
| + }
|
| +}
|
| +
|
| +/*
|
| +** pEList is the SET clause of an UPDATE statement. Each entry
|
| +** in pEList is of the format <id>=<expr>. If any of the entries
|
| +** in pEList have an <id> which matches an identifier in pIdList,
|
| +** then return TRUE. If pIdList==NULL, then it is considered a
|
| +** wildcard that matches anything. Likewise if pEList==NULL then
|
| +** it matches anything so always return true. Return false only
|
| +** if there is no match.
|
| +*/
|
| +static int checkColumnOverlap(IdList *pIdList, ExprList *pEList){
|
| + int e;
|
| + if( pIdList==0 || NEVER(pEList==0) ) return 1;
|
| + for(e=0; e<pEList->nExpr; e++){
|
| + if( sqlite3IdListIndex(pIdList, pEList->a[e].zName)>=0 ) return 1;
|
| + }
|
| + return 0;
|
| +}
|
| +
|
| +/*
|
| +** Return a list of all triggers on table pTab if there exists at least
|
| +** one trigger that must be fired when an operation of type 'op' is
|
| +** performed on the table, and, if that operation is an UPDATE, if at
|
| +** least one of the columns in pChanges is being modified.
|
| +*/
|
| +Trigger *sqlite3TriggersExist(
|
| + Parse *pParse, /* Parse context */
|
| + 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 */
|
| + int *pMask /* OUT: Mask of TRIGGER_BEFORE|TRIGGER_AFTER */
|
| +){
|
| + int mask = 0;
|
| + Trigger *pList = 0;
|
| + Trigger *p;
|
| +
|
| + if( (pParse->db->flags & SQLITE_EnableTrigger)!=0 ){
|
| + pList = sqlite3TriggerList(pParse, pTab);
|
| + }
|
| + assert( pList==0 || IsVirtual(pTab)==0 );
|
| + for(p=pList; p; p=p->pNext){
|
| + if( p->op==op && checkColumnOverlap(p->pColumns, pChanges) ){
|
| + mask |= p->tr_tm;
|
| + }
|
| + }
|
| + if( pMask ){
|
| + *pMask = mask;
|
| + }
|
| + return (mask ? pList : 0);
|
| +}
|
| +
|
| +/*
|
| +** Convert the pStep->target token into a SrcList and return a pointer
|
| +** to that SrcList.
|
| +**
|
| +** This routine adds a specific database name, if needed, to the target when
|
| +** forming the SrcList. This prevents a trigger in one database from
|
| +** referring to a target in another database. An exception is when the
|
| +** trigger is in TEMP in which case it can refer to any other database it
|
| +** wants.
|
| +*/
|
| +static SrcList *targetSrcList(
|
| + Parse *pParse, /* The parsing context */
|
| + TriggerStep *pStep /* The trigger containing the target token */
|
| +){
|
| + int iDb; /* Index of the database to use */
|
| + SrcList *pSrc; /* SrcList to be returned */
|
| +
|
| + pSrc = sqlite3SrcListAppend(pParse->db, 0, &pStep->target, 0);
|
| + if( pSrc ){
|
| + assert( pSrc->nSrc>0 );
|
| + assert( pSrc->a!=0 );
|
| + iDb = sqlite3SchemaToIndex(pParse->db, pStep->pTrig->pSchema);
|
| + if( iDb==0 || iDb>=2 ){
|
| + sqlite3 *db = pParse->db;
|
| + assert( iDb<pParse->db->nDb );
|
| + pSrc->a[pSrc->nSrc-1].zDatabase = sqlite3DbStrDup(db, db->aDb[iDb].zName);
|
| + }
|
| + }
|
| + return pSrc;
|
| +}
|
| +
|
| +/*
|
| +** Generate VDBE code for the statements inside the body of a single
|
| +** trigger.
|
| +*/
|
| +static int codeTriggerProgram(
|
| + Parse *pParse, /* The parser context */
|
| + TriggerStep *pStepList, /* List of statements inside the trigger body */
|
| + int orconf /* Conflict algorithm. (OE_Abort, etc) */
|
| +){
|
| + TriggerStep *pStep;
|
| + Vdbe *v = pParse->pVdbe;
|
| + sqlite3 *db = pParse->db;
|
| +
|
| + assert( pParse->pTriggerTab && pParse->pToplevel );
|
| + assert( pStepList );
|
| + assert( v!=0 );
|
| + for(pStep=pStepList; pStep; pStep=pStep->pNext){
|
| + /* Figure out the ON CONFLICT policy that will be used for this step
|
| + ** of the trigger program. If the statement that caused this trigger
|
| + ** to fire had an explicit ON CONFLICT, then use it. Otherwise, use
|
| + ** the ON CONFLICT policy that was specified as part of the trigger
|
| + ** step statement. Example:
|
| + **
|
| + ** CREATE TRIGGER AFTER INSERT ON t1 BEGIN;
|
| + ** INSERT OR REPLACE INTO t2 VALUES(new.a, new.b);
|
| + ** END;
|
| + **
|
| + ** INSERT INTO t1 ... ; -- insert into t2 uses REPLACE policy
|
| + ** INSERT OR IGNORE INTO t1 ... ; -- insert into t2 uses IGNORE policy
|
| + */
|
| + pParse->eOrconf = (orconf==OE_Default)?pStep->orconf:(u8)orconf;
|
| +
|
| + switch( pStep->op ){
|
| + case TK_UPDATE: {
|
| + sqlite3Update(pParse,
|
| + targetSrcList(pParse, pStep),
|
| + sqlite3ExprListDup(db, pStep->pExprList, 0),
|
| + sqlite3ExprDup(db, pStep->pWhere, 0),
|
| + pParse->eOrconf
|
| + );
|
| + break;
|
| + }
|
| + case TK_INSERT: {
|
| + sqlite3Insert(pParse,
|
| + targetSrcList(pParse, pStep),
|
| + sqlite3ExprListDup(db, pStep->pExprList, 0),
|
| + sqlite3SelectDup(db, pStep->pSelect, 0),
|
| + sqlite3IdListDup(db, pStep->pIdList),
|
| + pParse->eOrconf
|
| + );
|
| + break;
|
| + }
|
| + case TK_DELETE: {
|
| + sqlite3DeleteFrom(pParse,
|
| + targetSrcList(pParse, pStep),
|
| + sqlite3ExprDup(db, pStep->pWhere, 0)
|
| + );
|
| + break;
|
| + }
|
| + default: assert( pStep->op==TK_SELECT ); {
|
| + SelectDest sDest;
|
| + Select *pSelect = sqlite3SelectDup(db, pStep->pSelect, 0);
|
| + sqlite3SelectDestInit(&sDest, SRT_Discard, 0);
|
| + sqlite3Select(pParse, pSelect, &sDest);
|
| + sqlite3SelectDelete(db, pSelect);
|
| + break;
|
| + }
|
| + }
|
| + if( pStep->op!=TK_SELECT ){
|
| + sqlite3VdbeAddOp0(v, OP_ResetCount);
|
| + }
|
| + }
|
| +
|
| + return 0;
|
| +}
|
| +
|
| +#ifdef SQLITE_DEBUG
|
| +/*
|
| +** This function is used to add VdbeComment() annotations to a VDBE
|
| +** program. It is not used in production code, only for debugging.
|
| +*/
|
| +static const char *onErrorText(int onError){
|
| + switch( onError ){
|
| + case OE_Abort: return "abort";
|
| + case OE_Rollback: return "rollback";
|
| + case OE_Fail: return "fail";
|
| + case OE_Replace: return "replace";
|
| + case OE_Ignore: return "ignore";
|
| + case OE_Default: return "default";
|
| + }
|
| + return "n/a";
|
| +}
|
| +#endif
|
| +
|
| +/*
|
| +** Parse context structure pFrom has just been used to create a sub-vdbe
|
| +** (trigger program). If an error has occurred, transfer error information
|
| +** from pFrom to pTo.
|
| +*/
|
| +static void transferParseError(Parse *pTo, Parse *pFrom){
|
| + assert( pFrom->zErrMsg==0 || pFrom->nErr );
|
| + assert( pTo->zErrMsg==0 || pTo->nErr );
|
| + if( pTo->nErr==0 ){
|
| + pTo->zErrMsg = pFrom->zErrMsg;
|
| + pTo->nErr = pFrom->nErr;
|
| + }else{
|
| + sqlite3DbFree(pFrom->db, pFrom->zErrMsg);
|
| + }
|
| +}
|
| +
|
| +/*
|
| +** Create and populate a new TriggerPrg object with a sub-program
|
| +** implementing trigger pTrigger with ON CONFLICT policy orconf.
|
| +*/
|
| +static TriggerPrg *codeRowTrigger(
|
| + Parse *pParse, /* Current parse context */
|
| + Trigger *pTrigger, /* Trigger to code */
|
| + Table *pTab, /* The table pTrigger is attached to */
|
| + int orconf /* ON CONFLICT policy to code trigger program with */
|
| +){
|
| + Parse *pTop = sqlite3ParseToplevel(pParse);
|
| + sqlite3 *db = pParse->db; /* Database handle */
|
| + TriggerPrg *pPrg; /* Value to return */
|
| + Expr *pWhen = 0; /* Duplicate of trigger WHEN expression */
|
| + Vdbe *v; /* Temporary VM */
|
| + NameContext sNC; /* Name context for sub-vdbe */
|
| + SubProgram *pProgram = 0; /* Sub-vdbe for trigger program */
|
| + Parse *pSubParse; /* Parse context for sub-vdbe */
|
| + int iEndTrigger = 0; /* Label to jump to if WHEN is false */
|
| +
|
| + assert( pTrigger->zName==0 || pTab==tableOfTrigger(pTrigger) );
|
| + assert( pTop->pVdbe );
|
| +
|
| + /* Allocate the TriggerPrg and SubProgram objects. To ensure that they
|
| + ** are freed if an error occurs, link them into the Parse.pTriggerPrg
|
| + ** list of the top-level Parse object sooner rather than later. */
|
| + pPrg = sqlite3DbMallocZero(db, sizeof(TriggerPrg));
|
| + if( !pPrg ) return 0;
|
| + pPrg->pNext = pTop->pTriggerPrg;
|
| + pTop->pTriggerPrg = pPrg;
|
| + pPrg->pProgram = pProgram = sqlite3DbMallocZero(db, sizeof(SubProgram));
|
| + if( !pProgram ) return 0;
|
| + sqlite3VdbeLinkSubProgram(pTop->pVdbe, pProgram);
|
| + pPrg->pTrigger = pTrigger;
|
| + pPrg->orconf = orconf;
|
| + pPrg->aColmask[0] = 0xffffffff;
|
| + pPrg->aColmask[1] = 0xffffffff;
|
| +
|
| + /* Allocate and populate a new Parse context to use for coding the
|
| + ** trigger sub-program. */
|
| + pSubParse = sqlite3StackAllocZero(db, sizeof(Parse));
|
| + if( !pSubParse ) return 0;
|
| + memset(&sNC, 0, sizeof(sNC));
|
| + sNC.pParse = pSubParse;
|
| + pSubParse->db = db;
|
| + pSubParse->pTriggerTab = pTab;
|
| + pSubParse->pToplevel = pTop;
|
| + pSubParse->zAuthContext = pTrigger->zName;
|
| + pSubParse->eTriggerOp = pTrigger->op;
|
| + pSubParse->nQueryLoop = pParse->nQueryLoop;
|
| +
|
| + v = sqlite3GetVdbe(pSubParse);
|
| + if( v ){
|
| + VdbeComment((v, "Start: %s.%s (%s %s%s%s ON %s)",
|
| + pTrigger->zName, onErrorText(orconf),
|
| + (pTrigger->tr_tm==TRIGGER_BEFORE ? "BEFORE" : "AFTER"),
|
| + (pTrigger->op==TK_UPDATE ? "UPDATE" : ""),
|
| + (pTrigger->op==TK_INSERT ? "INSERT" : ""),
|
| + (pTrigger->op==TK_DELETE ? "DELETE" : ""),
|
| + pTab->zName
|
| + ));
|
| +#ifndef SQLITE_OMIT_TRACE
|
| + sqlite3VdbeChangeP4(v, -1,
|
| + sqlite3MPrintf(db, "-- TRIGGER %s", pTrigger->zName), P4_DYNAMIC
|
| + );
|
| +#endif
|
| +
|
| + /* If one was specified, code the WHEN clause. If it evaluates to false
|
| + ** (or NULL) the sub-vdbe is immediately halted by jumping to the
|
| + ** OP_Halt inserted at the end of the program. */
|
| + if( pTrigger->pWhen ){
|
| + pWhen = sqlite3ExprDup(db, pTrigger->pWhen, 0);
|
| + if( SQLITE_OK==sqlite3ResolveExprNames(&sNC, pWhen)
|
| + && db->mallocFailed==0
|
| + ){
|
| + iEndTrigger = sqlite3VdbeMakeLabel(v);
|
| + sqlite3ExprIfFalse(pSubParse, pWhen, iEndTrigger, SQLITE_JUMPIFNULL);
|
| + }
|
| + sqlite3ExprDelete(db, pWhen);
|
| + }
|
| +
|
| + /* Code the trigger program into the sub-vdbe. */
|
| + codeTriggerProgram(pSubParse, pTrigger->step_list, orconf);
|
| +
|
| + /* Insert an OP_Halt at the end of the sub-program. */
|
| + if( iEndTrigger ){
|
| + sqlite3VdbeResolveLabel(v, iEndTrigger);
|
| + }
|
| + sqlite3VdbeAddOp0(v, OP_Halt);
|
| + VdbeComment((v, "End: %s.%s", pTrigger->zName, onErrorText(orconf)));
|
| +
|
| + transferParseError(pParse, pSubParse);
|
| + if( db->mallocFailed==0 ){
|
| + pProgram->aOp = sqlite3VdbeTakeOpArray(v, &pProgram->nOp, &pTop->nMaxArg);
|
| + }
|
| + pProgram->nMem = pSubParse->nMem;
|
| + pProgram->nCsr = pSubParse->nTab;
|
| + pProgram->token = (void *)pTrigger;
|
| + pPrg->aColmask[0] = pSubParse->oldmask;
|
| + pPrg->aColmask[1] = pSubParse->newmask;
|
| + sqlite3VdbeDelete(v);
|
| + }
|
| +
|
| + assert( !pSubParse->pAinc && !pSubParse->pZombieTab );
|
| + assert( !pSubParse->pTriggerPrg && !pSubParse->nMaxArg );
|
| + sqlite3StackFree(db, pSubParse);
|
| +
|
| + return pPrg;
|
| +}
|
| +
|
| +/*
|
| +** Return a pointer to a TriggerPrg object containing the sub-program for
|
| +** trigger pTrigger with default ON CONFLICT algorithm orconf. If no such
|
| +** TriggerPrg object exists, a new object is allocated and populated before
|
| +** being returned.
|
| +*/
|
| +static TriggerPrg *getRowTrigger(
|
| + Parse *pParse, /* Current parse context */
|
| + Trigger *pTrigger, /* Trigger to code */
|
| + Table *pTab, /* The table trigger pTrigger is attached to */
|
| + int orconf /* ON CONFLICT algorithm. */
|
| +){
|
| + Parse *pRoot = sqlite3ParseToplevel(pParse);
|
| + TriggerPrg *pPrg;
|
| +
|
| + assert( pTrigger->zName==0 || pTab==tableOfTrigger(pTrigger) );
|
| +
|
| + /* It may be that this trigger has already been coded (or is in the
|
| + ** process of being coded). If this is the case, then an entry with
|
| + ** a matching TriggerPrg.pTrigger field will be present somewhere
|
| + ** in the Parse.pTriggerPrg list. Search for such an entry. */
|
| + for(pPrg=pRoot->pTriggerPrg;
|
| + pPrg && (pPrg->pTrigger!=pTrigger || pPrg->orconf!=orconf);
|
| + pPrg=pPrg->pNext
|
| + );
|
| +
|
| + /* If an existing TriggerPrg could not be located, create a new one. */
|
| + if( !pPrg ){
|
| + pPrg = codeRowTrigger(pParse, pTrigger, pTab, orconf);
|
| + }
|
| +
|
| + return pPrg;
|
| +}
|
| +
|
| +/*
|
| +** Generate code for the trigger program associated with trigger p on
|
| +** table pTab. The reg, orconf and ignoreJump parameters passed to this
|
| +** function are the same as those described in the header function for
|
| +** sqlite3CodeRowTrigger()
|
| +*/
|
| +void sqlite3CodeRowTriggerDirect(
|
| + Parse *pParse, /* Parse context */
|
| + Trigger *p, /* Trigger to code */
|
| + Table *pTab, /* The table to code triggers from */
|
| + int reg, /* Reg array containing OLD.* and NEW.* values */
|
| + int orconf, /* ON CONFLICT policy */
|
| + int ignoreJump /* Instruction to jump to for RAISE(IGNORE) */
|
| +){
|
| + Vdbe *v = sqlite3GetVdbe(pParse); /* Main VM */
|
| + TriggerPrg *pPrg;
|
| + pPrg = getRowTrigger(pParse, p, pTab, orconf);
|
| + assert( pPrg || pParse->nErr || pParse->db->mallocFailed );
|
| +
|
| + /* Code the OP_Program opcode in the parent VDBE. P4 of the OP_Program
|
| + ** is a pointer to the sub-vdbe containing the trigger program. */
|
| + if( pPrg ){
|
| + int bRecursive = (p->zName && 0==(pParse->db->flags&SQLITE_RecTriggers));
|
| +
|
| + sqlite3VdbeAddOp3(v, OP_Program, reg, ignoreJump, ++pParse->nMem);
|
| + sqlite3VdbeChangeP4(v, -1, (const char *)pPrg->pProgram, P4_SUBPROGRAM);
|
| + VdbeComment(
|
| + (v, "Call: %s.%s", (p->zName?p->zName:"fkey"), onErrorText(orconf)));
|
| +
|
| + /* Set the P5 operand of the OP_Program instruction to non-zero if
|
| + ** recursive invocation of this trigger program is disallowed. Recursive
|
| + ** invocation is disallowed if (a) the sub-program is really a trigger,
|
| + ** not a foreign key action, and (b) the flag to enable recursive triggers
|
| + ** is clear. */
|
| + sqlite3VdbeChangeP5(v, (u8)bRecursive);
|
| + }
|
| +}
|
| +
|
| +/*
|
| +** This is called to code the required FOR EACH ROW triggers for an operation
|
| +** on table pTab. The operation to code triggers for (INSERT, UPDATE or DELETE)
|
| +** is given by the op paramater. The tr_tm parameter determines whether the
|
| +** BEFORE or AFTER triggers are coded. If the operation is an UPDATE, then
|
| +** parameter pChanges is passed the list of columns being modified.
|
| +**
|
| +** If there are no triggers that fire at the specified time for the specified
|
| +** operation on pTab, this function is a no-op.
|
| +**
|
| +** The reg argument is the address of the first in an array of registers
|
| +** that contain the values substituted for the new.* and old.* references
|
| +** in the trigger program. If N is the number of columns in table pTab
|
| +** (a copy of pTab->nCol), then registers are populated as follows:
|
| +**
|
| +** Register Contains
|
| +** ------------------------------------------------------
|
| +** reg+0 OLD.rowid
|
| +** reg+1 OLD.* value of left-most column of pTab
|
| +** ... ...
|
| +** reg+N OLD.* value of right-most column of pTab
|
| +** reg+N+1 NEW.rowid
|
| +** reg+N+2 OLD.* value of left-most column of pTab
|
| +** ... ...
|
| +** reg+N+N+1 NEW.* value of right-most column of pTab
|
| +**
|
| +** For ON DELETE triggers, the registers containing the NEW.* values will
|
| +** never be accessed by the trigger program, so they are not allocated or
|
| +** populated by the caller (there is no data to populate them with anyway).
|
| +** Similarly, for ON INSERT triggers the values stored in the OLD.* registers
|
| +** are never accessed, and so are not allocated by the caller. So, for an
|
| +** ON INSERT trigger, the value passed to this function as parameter reg
|
| +** is not a readable register, although registers (reg+N) through
|
| +** (reg+N+N+1) are.
|
| +**
|
| +** Parameter orconf is the default conflict resolution algorithm for the
|
| +** trigger program to use (REPLACE, IGNORE etc.). Parameter ignoreJump
|
| +** is the instruction that control should jump to if a trigger program
|
| +** raises an IGNORE exception.
|
| +*/
|
| +void 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 reg, /* The first in an array of registers (see above) */
|
| + int orconf, /* ON CONFLICT policy */
|
| + int ignoreJump /* Instruction to jump to for RAISE(IGNORE) */
|
| +){
|
| + Trigger *p; /* Used to iterate through pTrigger list */
|
| +
|
| + assert( op==TK_UPDATE || op==TK_INSERT || op==TK_DELETE );
|
| + assert( tr_tm==TRIGGER_BEFORE || tr_tm==TRIGGER_AFTER );
|
| + assert( (op==TK_UPDATE)==(pChanges!=0) );
|
| +
|
| + for(p=pTrigger; p; p=p->pNext){
|
| +
|
| + /* 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. */
|
| + assert( p->pSchema!=0 );
|
| + assert( p->pTabSchema!=0 );
|
| + assert( p->pSchema==p->pTabSchema
|
| + || p->pSchema==pParse->db->aDb[1].pSchema );
|
| +
|
| + /* Determine whether we should code this trigger */
|
| + if( p->op==op
|
| + && p->tr_tm==tr_tm
|
| + && checkColumnOverlap(p->pColumns, pChanges)
|
| + ){
|
| + sqlite3CodeRowTriggerDirect(pParse, p, pTab, reg, orconf, ignoreJump);
|
| + }
|
| + }
|
| +}
|
| +
|
| +/*
|
| +** Triggers may access values stored in the old.* or new.* pseudo-table.
|
| +** This function returns a 32-bit bitmask indicating which columns of the
|
| +** old.* or new.* tables actually are used by triggers. This information
|
| +** may be used by the caller, for example, to avoid having to load the entire
|
| +** old.* record into memory when executing an UPDATE or DELETE command.
|
| +**
|
| +** Bit 0 of the returned mask is set if the left-most column of the
|
| +** table may be accessed using an [old|new].<col> reference. Bit 1 is set if
|
| +** the second leftmost column value is required, and so on. If there
|
| +** are more than 32 columns in the table, and at least one of the columns
|
| +** with an index greater than 32 may be accessed, 0xffffffff is returned.
|
| +**
|
| +** It is not possible to determine if the old.rowid or new.rowid column is
|
| +** accessed by triggers. The caller must always assume that it is.
|
| +**
|
| +** Parameter isNew must be either 1 or 0. If it is 0, then the mask returned
|
| +** applies to the old.* table. If 1, the new.* table.
|
| +**
|
| +** Parameter tr_tm must be a mask with one or both of the TRIGGER_BEFORE
|
| +** and TRIGGER_AFTER bits set. Values accessed by BEFORE triggers are only
|
| +** included in the returned mask if the TRIGGER_BEFORE bit is set in the
|
| +** tr_tm parameter. Similarly, values accessed by AFTER triggers are only
|
| +** included in the returned mask if the TRIGGER_AFTER bit is set in tr_tm.
|
| +*/
|
| +u32 sqlite3TriggerColmask(
|
| + Parse *pParse, /* Parse context */
|
| + Trigger *pTrigger, /* List of triggers on table pTab */
|
| + ExprList *pChanges, /* Changes list for any UPDATE OF triggers */
|
| + int isNew, /* 1 for new.* ref mask, 0 for old.* ref mask */
|
| + int tr_tm, /* Mask of TRIGGER_BEFORE|TRIGGER_AFTER */
|
| + Table *pTab, /* The table to code triggers from */
|
| + int orconf /* Default ON CONFLICT policy for trigger steps */
|
| +){
|
| + const int op = pChanges ? TK_UPDATE : TK_DELETE;
|
| + u32 mask = 0;
|
| + Trigger *p;
|
| +
|
| + assert( isNew==1 || isNew==0 );
|
| + for(p=pTrigger; p; p=p->pNext){
|
| + if( p->op==op && (tr_tm&p->tr_tm)
|
| + && checkColumnOverlap(p->pColumns,pChanges)
|
| + ){
|
| + TriggerPrg *pPrg;
|
| + pPrg = getRowTrigger(pParse, p, pTab, orconf);
|
| + if( pPrg ){
|
| + mask |= pPrg->aColmask[isNew];
|
| + }
|
| + }
|
| + }
|
| +
|
| + return mask;
|
| +}
|
| +
|
| +#endif /* !defined(SQLITE_OMIT_TRIGGER) */
|
|
|