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);
}
}
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);
}