77 *
88 *
99 * IDENTIFICATION
10- * $Header: /cvsroot/pgsql/src/backend/commands/async.c,v 1.12 1997/01/24 23:48:25 scrappy Exp $
10+ * $Header: /cvsroot/pgsql/src/backend/commands/async.c,v 1.13 1997/03/10 00:18:09 scrappy Exp $
1111 *
1212 *-------------------------------------------------------------------------
1313 */
8484
8585#include <port-protos.h> /* for strdup() */
8686
87+ #include <storage/lmgr.h>
88+
8789static int notifyFrontEndPending = 0 ;
8890static int notifyIssued = 0 ;
8991static Dllist * pendingNotifies = NULL ;
@@ -194,6 +196,7 @@ Async_Notify(char *relname)
194196
195197lRel = heap_openr (ListenerRelationName );
196198tdesc = RelationGetTupleDescriptor (lRel );
199+ RelationSetLockForWrite (lRel );
197200sRel = heap_beginscan (lRel ,0 ,NowTimeQual ,1 ,& key );
198201
199202nulls [0 ]= nulls [1 ]= nulls [2 ]= ' ' ;
@@ -212,6 +215,7 @@ Async_Notify(char *relname)
212215ReleaseBuffer (b );
213216 }
214217heap_endscan (sRel );
218+ RelationUnsetLockForWrite (lRel );
215219heap_close (lRel );
216220notifyIssued = 1 ;
217221}
@@ -269,6 +273,7 @@ Async_NotifyAtCommit()
269273Integer32EqualRegProcedure ,
270274Int32GetDatum (1 ));
271275lRel = heap_openr (ListenerRelationName );
276+ RelationSetLockForWrite (lRel );
272277sRel = heap_beginscan (lRel ,0 ,NowTimeQual ,1 ,& key );
273278tdesc = RelationGetTupleDescriptor (lRel );
274279ourpid = getpid ();
@@ -302,6 +307,7 @@ Async_NotifyAtCommit()
302307ReleaseBuffer (b );
303308 }
304309heap_endscan (sRel );
310+ RelationUnsetLockForWrite (lRel );
305311heap_close (lRel );
306312
307313CommitTransactionCommand ();
@@ -405,6 +411,7 @@ Async_Listen(char *relname, int pid)
405411values [i ++ ]= (Datum )0 ;/* no notifies pending */
406412
407413lDesc = heap_openr (ListenerRelationName );
414+ RelationSetLockForWrite (lDesc );
408415
409416/* is someone already listening. One listener per relation */
410417tdesc = RelationGetTupleDescriptor (lDesc );
@@ -440,6 +447,8 @@ Async_Listen(char *relname, int pid)
440447/* if (alreadyListener) {
441448 elog(NOTICE,"Async_Listen: already one listener on %s (possibly dead)",relname);
442449 }*/
450+
451+ RelationUnsetLockForWrite (lDesc );
443452heap_close (lDesc );
444453
445454/*
@@ -480,9 +489,13 @@ Async_Unlisten(char *relname, int pid)
480489Int32GetDatum (pid ),
4814900 ,0 );
482491lDesc = heap_openr (ListenerRelationName );
492+ RelationSetLockForWrite (lDesc );
493+
483494if (lTuple != NULL ) {
484495heap_delete (lDesc ,& lTuple -> t_ctid );
485496 }
497+
498+ RelationUnsetLockForWrite (lDesc );
486499heap_close (lDesc );
487500}
488501
@@ -549,6 +562,7 @@ Async_NotifyFrontEnd()
549562Integer32EqualRegProcedure ,
550563Int32GetDatum (ourpid ));
551564lRel = heap_openr (ListenerRelationName );
565+ RelationSetLockForWrite (lRel );
552566tdesc = RelationGetTupleDescriptor (lRel );
553567sRel = heap_beginscan (lRel ,0 ,NowTimeQual ,2 ,key );
554568