Ejemplo n.º 1
0
        public static void BeginTrigger(Parse parse, Token name1, Token name2, TK trTm, TK op, IdList columns, SrcList tableName, Expr when, bool isTemp, int noErr)
        {
            Context ctx = parse.Ctx;     // The database connection

            Debug.Assert(name1 != null); // pName1.z might be NULL, but not pName1 itself
            Debug.Assert(name2 != null);
            Debug.Assert(op == TK.INSERT || op == TK.UPDATE || op == TK.DELETE);
            Debug.Assert(op > 0 && op < (TK)0xff);
            Trigger trigger = null; // The new trigger

            int   db;               // The database to store the trigger in
            Token name = null;      // The unqualified db name

            if (isTemp)
            {
                // If TEMP was specified, then the trigger name may not be qualified.
                if (name2.length > 0)
                {
                    parse.ErrorMsg("temporary trigger may not have qualified name");
                    goto trigger_cleanup;
                }
                db   = 1;
                name = name1;
            }
            else
            {
                // Figure out the db that the the trigger will be created in
                db = parse.TwoPartName(name1, name2, ref name);
                if (db < 0)
                {
                    goto trigger_cleanup;
                }
            }
            if (tableName == null || ctx.MallocFailed)
            {
                goto trigger_cleanup;
            }

            // A long-standing parser bug is that this syntax was allowed:
            //    CREATE TRIGGER attached.demo AFTER INSERT ON attached.tab ....
            //                                                 ^^^^^^^^
            // To maintain backwards compatibility, ignore the database name on pTableName if we are reparsing our of SQLITE_MASTER.
            if (ctx.Init.Busy && db != 1)
            {
                C._tagfree(ctx, ref tableName.Ids[0].Database);
                tableName.Ids[0].Database = null;
            }

            // 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 (tableName == null) goto trigger_cleanup;
            Table table = Delete.SrcListLookup(parse, tableName); // Table that the trigger fires off of

            if (ctx.Init.Busy == null && name2.length == 0 && table != null && table.Schema == ctx.DBs[1].Schema)
            {
                db = 1;
            }

            // Ensure the table name matches database name and that the table exists
            if (ctx.MallocFailed)
            {
                goto trigger_cleanup;
            }
            Debug.Assert(tableName.Srcs == 1);
            DbFixer sFix = new DbFixer(); // State vector for the DB fixer

            if (sFix.FixInit(parse, db, "trigger", name) && sFix.FixSrcList(tableName))
            {
                goto trigger_cleanup;
            }
            table = Delete.SrcListLookup(parse, tableName);
            if (table == null)
            {
                // The table does not exist.
                if (ctx.Init.DB == 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.
                    ctx.Init.OrphanTrigger = true;
                }
                goto trigger_cleanup;
            }
            if (E.IsVirtual(table))
            {
                parse.ErrorMsg("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
            string nameAsString = Parse.NameFromToken(ctx, name);

            if (nameAsString == null || parse.CheckObjectName(nameAsString) != RC.OK)
            {
                goto trigger_cleanup;
            }
            Debug.Assert(Btree.SchemaMutexHeld(ctx, db, null));
            if (ctx.DBs[db].Schema.TriggerHash.Find(nameAsString, nameAsString.Length, (Trigger)null) != null)
            {
                if (noErr == 0)
                {
                    parse.ErrorMsg("trigger %T already exists", name);
                }
                else
                {
                    Debug.Assert(!ctx.Init.Busy);
                    parse.CodeVerifySchema(db);
                }
                goto trigger_cleanup;
            }

            // Do not create a trigger on a system table
            if (table.Name.StartsWith("sqlite_", StringComparison.InvariantCultureIgnoreCase))
            {
                parse.ErrorMsg("cannot create trigger on system table");
                parse.Errs++;
                goto trigger_cleanup;
            }

            // INSTEAD of triggers are only for views and views only support INSTEAD of triggers.
            if (table.Select != null && trTm != TK.INSTEAD)
            {
                parse.ErrorMsg("cannot create %s trigger on view: %S", (trTm == TK.BEFORE ? "BEFORE" : "AFTER"), tableName, 0);
                goto trigger_cleanup;
            }
            if (table.Select == null && trTm == TK.INSTEAD)
            {
                parse.ErrorMsg("cannot create INSTEAD OF trigger on table: %S", tableName, 0);
                goto trigger_cleanup;
            }

#if !OMIT_AUTHORIZATION
            {
                int    tabDb      = Prepare.SchemaToIndex(ctx, table.Schema); // Index of the database holding pTab
                AUTH   code       = AUTH.CREATE_TRIGGER;
                string dbName     = ctx.DBs[tabDb].Name;
                string dbTrigName = (isTemp ? ctx.DBs[1].Name : dbName);
                if (tabDb == 1 || isTemp)
                {
                    code = AUTH.CREATE_TEMP_TRIGGER;
                }
                if (Auth.Check(parse, code, nameAsString, table.Name, dbTrigName) != 0 || Auth.Check(parse, AUTH.INSERT, E.SCHEMA_TABLE(tabDb), 0, dbName))
                {
                    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 (trTm == TK.INSTEAD)
            {
                trTm = TK.BEFORE;
            }

            // Build the Trigger object
            trigger = new Trigger(); //: (Trigger *)_tagalloc(db, sizeof(Trigger), true);
            if (trigger == null)
            {
                goto trigger_cleanup;
            }
            trigger.Name      = name;
            trigger.Table     = tableName.Ids[0].Name; //: _tagstrdup(ctx, tableName->Ids[0].Name);
            trigger.Schema    = ctx.DBs[db].Schema;
            trigger.TabSchema = table.Schema;
            trigger.OP        = op;
            trigger.TRtm      = (trTm == TK.BEFORE ? TRIGGER.BEFORE : TRIGGER.AFTER);
            trigger.When      = Expr.Dup(db, when, E.EXPRDUP_REDUCE);
            trigger.Columns   = Expr.IdListDup(ctx, columns);
            Debug.Assert(parse.NewTrigger == null);
            parse.NewTrigger = trigger;

trigger_cleanup:
            C._tagfree(ctx, ref name);
            Expr.SrcListDelete(ctx, ref tableName);
            Expr.IdListDelete(ctx, ref columns);
            Expr.Delete(ctx, ref when);
            if (parse.NewTrigger == null)
            {
                DeleteTrigger(ctx, ref trigger);
            }
            else
            {
                Debug.Assert(parse.NewTrigger == trigger);
            }
        }
Ejemplo n.º 2
0
        public static void BeginTrigger(Parse parse, Token name1, Token name2, TK trTm, TK op, IdList columns, SrcList tableName, Expr when, bool isTemp, int noErr)
        {
            Context ctx = parse.Ctx; // The database connection
            Debug.Assert(name1 != null);   // pName1.z might be NULL, but not pName1 itself
            Debug.Assert(name2 != null);
            Debug.Assert(op == TK.INSERT || op == TK.UPDATE || op == TK.DELETE);
            Debug.Assert(op > 0 && op < (TK)0xff);
            Trigger trigger = null; // The new trigger

            int db; // The database to store the trigger in
            Token name = null; // The unqualified db name
            if (isTemp)
            {
                // If TEMP was specified, then the trigger name may not be qualified.
                if (name2.length > 0)
                {
                    parse.ErrorMsg("temporary trigger may not have qualified name");
                    goto trigger_cleanup;
                }
                db = 1;
                name = name1;
            }
            else
            {
                // Figure out the db that the the trigger will be created in
                db = parse.TwoPartName(name1, name2, ref name);
                if (db < 0)
                    goto trigger_cleanup;
            }
            if (tableName == null || ctx.MallocFailed)
                goto trigger_cleanup;

            // A long-standing parser bug is that this syntax was allowed:
            //    CREATE TRIGGER attached.demo AFTER INSERT ON attached.tab ....
            //                                                 ^^^^^^^^
            // To maintain backwards compatibility, ignore the database name on pTableName if we are reparsing our of SQLITE_MASTER.
            if (ctx.Init.Busy && db != 1)
            {
                C._tagfree(ctx, ref tableName.Ids[0].Database);
                tableName.Ids[0].Database = null;
            }

            // 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 (tableName == null) goto trigger_cleanup;
            Table table = Delete.SrcListLookup(parse, tableName); // Table that the trigger fires off of
            if (ctx.Init.Busy == null && name2.length == 0 && table != null && table.Schema == ctx.DBs[1].Schema)
                db = 1;

            // Ensure the table name matches database name and that the table exists
            if (ctx.MallocFailed) goto trigger_cleanup;
            Debug.Assert(tableName.Srcs == 1);
            DbFixer sFix = new DbFixer(); // State vector for the DB fixer
            if (sFix.FixInit(parse, db, "trigger", name) && sFix.FixSrcList(tableName))
                goto trigger_cleanup;
            table = Delete.SrcListLookup(parse, tableName);
            if (table == null)
            {
                // The table does not exist.
                if (ctx.Init.DB == 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.
                    ctx.Init.OrphanTrigger = true;
                }
                goto trigger_cleanup;
            }
            if (E.IsVirtual(table))
            {
                parse.ErrorMsg("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
            string nameAsString = Parse.NameFromToken(ctx, name);
            if (nameAsString == null || parse.CheckObjectName(nameAsString) != RC.OK)
                goto trigger_cleanup;
            Debug.Assert(Btree.SchemaMutexHeld(ctx, db, null));
            if (ctx.DBs[db].Schema.TriggerHash.Find(nameAsString, nameAsString.Length, (Trigger)null) != null)
            {
                if (noErr == 0)
                    parse.ErrorMsg("trigger %T already exists", name);
                else
                {
                    Debug.Assert(!ctx.Init.Busy);
                    parse.CodeVerifySchema(db);
                }
                goto trigger_cleanup;
            }

            // Do not create a trigger on a system table
            if (table.Name.StartsWith("sqlite_", StringComparison.InvariantCultureIgnoreCase))
            {
                parse.ErrorMsg("cannot create trigger on system table");
                parse.Errs++;
                goto trigger_cleanup;
            }

            // INSTEAD of triggers are only for views and views only support INSTEAD of triggers.
            if (table.Select != null && trTm != TK.INSTEAD)
            {
                parse.ErrorMsg("cannot create %s trigger on view: %S", (trTm == TK.BEFORE ? "BEFORE" : "AFTER"), tableName, 0);
                goto trigger_cleanup;
            }
            if (table.Select == null && trTm == TK.INSTEAD)
            {
                parse.ErrorMsg("cannot create INSTEAD OF trigger on table: %S", tableName, 0);
                goto trigger_cleanup;
            }

#if !OMIT_AUTHORIZATION
            {
                int tabDb = Prepare.SchemaToIndex(ctx, table.Schema); // Index of the database holding pTab
                AUTH code = AUTH.CREATE_TRIGGER;
                string dbName = ctx.DBs[tabDb].Name;
                string dbTrigName = (isTemp ? ctx.DBs[1].Name : dbName);
                if (tabDb == 1 || isTemp) code = AUTH.CREATE_TEMP_TRIGGER;
                if (Auth.Check(parse, code, nameAsString, table.Name, dbTrigName) != 0 || Auth.Check(parse, AUTH.INSERT, E.SCHEMA_TABLE(tabDb), 0, dbName))
                    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 (trTm == TK.INSTEAD)
                trTm = TK.BEFORE;

            // Build the Trigger object
            trigger = new Trigger(); //: (Trigger *)_tagalloc(db, sizeof(Trigger), true);
            if (trigger == null) goto trigger_cleanup;
            trigger.Name = name;
            trigger.Table = tableName.Ids[0].Name; //: _tagstrdup(ctx, tableName->Ids[0].Name);
            trigger.Schema = ctx.DBs[db].Schema;
            trigger.TabSchema = table.Schema;
            trigger.OP = op;
            trigger.TRtm = (trTm == TK.BEFORE ? TRIGGER.BEFORE : TRIGGER.AFTER);
            trigger.When = Expr.Dup(db, when, E.EXPRDUP_REDUCE);
            trigger.Columns = Expr.IdListDup(ctx, columns);
            Debug.Assert(parse.NewTrigger == null);
            parse.NewTrigger = trigger;

        trigger_cleanup:
            C._tagfree(ctx, ref name);
            Expr.SrcListDelete(ctx, ref tableName);
            Expr.IdListDelete(ctx, ref columns);
            Expr.Delete(ctx, ref when);
            if (parse.NewTrigger == null)
                DeleteTrigger(ctx, ref trigger);
            else
                Debug.Assert(parse.NewTrigger == trigger);
        }
Ejemplo n.º 3
0
        public static void FinishTrigger(Parse parse, TriggerStep stepList, Token all)
        {
            Trigger trig      = parse.NewTrigger; // Trigger being finished
            Context ctx       = parse.Ctx;        // The database
            Token   nameToken = new Token();      // Trigger name for error reporting

            parse.NewTrigger = null;
            if (C._NEVER(parse.Errs != 0) || trig == null)
            {
                goto triggerfinish_cleanup;
            }
            string name = trig.Name;                                     // Name of trigger
            int    db   = Prepare.SchemaToIndex(parse.Ctx, trig.Schema); // Database containing the trigger

            trig.StepList = stepList;
            while (stepList != null)
            {
                stepList.Trig = trig;
                stepList      = stepList.Next;
            }
            nameToken.data   = trig.Name;
            nameToken.length = (uint)nameToken.data.Length;
            DbFixer sFix = new DbFixer(); // Fixer object

            if (sFix.FixInit(parse, db, "trigger", nameToken) && sFix.FixTriggerStep(trig.StepList))
            {
                goto triggerfinish_cleanup;
            }

            // if we are not initializing, build the sqlite_master entry
            if (ctx.Init.Busy)
            {
                // Make an entry in the sqlite_master table
                Vdbe v = parse.GetVdbe();
                if (v == null)
                {
                    goto triggerfinish_cleanup;
                }
                parse.BeginWriteOperation(0, db);
                string z = all.data.Substring(0, (int)all.length); //: _tagstrndup(ctx, (char *)all->data, all->length);
                parse.NestedParse("INSERT INTO %Q.%s VALUES('trigger',%Q,%Q,0,'CREATE TRIGGER %q')", ctx.DBs[db].Name, E.SCHEMA_TABLE(db), name, trig.Table, z);
                C._tagfree(ctx, ref z);
                parse.ChangeCookie(db);
                v.AddParseSchemaOp(db, C._mtagprintf(ctx, "type='trigger' AND name='%q'", name));
            }

            if (!ctx.Init.Busy)
            {
                Trigger link = trig;
                Debug.Assert(Btree.SchemaMutexHeld(ctx, db, null));
                trig = ctx.DBs[db].Schema.TriggerHash.Insert(name, name.Length, trig);
                if (trig != null)
                {
                    ctx.MallocFailed = true;
                }
                else if (link.Schema == link.TabSchema)
                {
                    int   tableLength = link.Table.Length;
                    Table table       = (Table)link.TabSchema.TableHash.Find(link.Table, tableLength, (Table)null);
                    Debug.Assert(table != null);
                    link.Next      = table.Triggers;
                    table.Triggers = link;
                }
            }

triggerfinish_cleanup:
            DeleteTrigger(ctx, ref trig);
            Debug.Assert(parse.NewTrigger == null);
            DeleteTriggerStep(ctx, ref stepList);
        }
Ejemplo n.º 4
0
        public static void FinishTrigger(Parse parse, TriggerStep stepList, Token all)
        {
            Trigger trig = parse.NewTrigger; // Trigger being finished
            Context ctx = parse.Ctx; // The database
            Token nameToken = new Token(); // Trigger name for error reporting

            parse.NewTrigger = null;
            if (C._NEVER(parse.Errs != 0) || trig == null) goto triggerfinish_cleanup;
            string name = trig.Name; // Name of trigger
            int db = Prepare.SchemaToIndex(parse.Ctx, trig.Schema); // Database containing the trigger
            trig.StepList = stepList;
            while (stepList != null)
            {
                stepList.Trig = trig;
                stepList = stepList.Next;
            }
            nameToken.data = trig.Name;
            nameToken.length = (uint)nameToken.data.Length;
            DbFixer sFix = new DbFixer(); // Fixer object
            if (sFix.FixInit(parse, db, "trigger", nameToken) && sFix.FixTriggerStep(trig.StepList))
                goto triggerfinish_cleanup;

            // if we are not initializing, build the sqlite_master entry
            if (ctx.Init.Busy)
            {
                // Make an entry in the sqlite_master table
                Vdbe v = parse.GetVdbe();
                if (v == null) goto triggerfinish_cleanup;
                parse.BeginWriteOperation(0, db);
                string z = all.data.Substring(0, (int)all.length); //: _tagstrndup(ctx, (char *)all->data, all->length);
                parse.NestedParse("INSERT INTO %Q.%s VALUES('trigger',%Q,%Q,0,'CREATE TRIGGER %q')", ctx.DBs[db].Name, E.SCHEMA_TABLE(db), name, trig.Table, z);
                C._tagfree(ctx, ref z);
                parse.ChangeCookie(db);
                v.AddParseSchemaOp(db, C._mtagprintf(ctx, "type='trigger' AND name='%q'", name));
            }

            if (!ctx.Init.Busy)
            {
                Trigger link = trig;
                Debug.Assert(Btree.SchemaMutexHeld(ctx, db, null));
                trig = ctx.DBs[db].Schema.TriggerHash.Insert(name, name.Length, trig);
                if (trig != null)
                    ctx.MallocFailed = true;
                else if (link.Schema == link.TabSchema)
                {
                    int tableLength = link.Table.Length;
                    Table table = (Table)link.TabSchema.TableHash.Find(link.Table, tableLength, (Table)null);
                    Debug.Assert(table != null);
                    link.Next = table.Triggers;
                    table.Triggers = link;
                }
            }

        triggerfinish_cleanup:
            DeleteTrigger(ctx, ref trig);
            Debug.Assert(parse.NewTrigger == null);
            DeleteTriggerStep(ctx, ref stepList);
        }