Lock relation in pglogical_apply: fix possible source of #1582

Author: knizhnik

contrib/mmts/pglogical_apply.c

@@ -744,13 +744,14 @@ read_rel(StringInfo s, LOCKMODE mode)
 		old_context = MemoryContextSwitchTo(TopMemoryContext);
 		pglogical_relid_map_put(remote_relid, local_relid);
 		MemoryContextSwitchTo(old_context);
+		return heap_open(local_relid, NoLock);
 	} else { 
 		nspnamelen = pq_getmsgbyte(s);
 		s->cursor += nspnamelen;
 		relnamelen = pq_getmsgbyte(s);
 		s->cursor += relnamelen;
+		return heap_open(local_relid, mode);
 	}
-	return heap_open(local_relid, NoLock);
 }
 
 static void

src/backend/access/transam/twophase.c

@@ -2616,6 +2616,7 @@ GetLoggedPreparedXactState(char const *gid)
 	GetOldestRestartPoint(&start_lsn, &timeline);
 	if (start_lsn != InvalidXLogRecPtr)
 	{
+		MemoryContext memctx = CurrentMemoryContext;
 		xlogreader = XLogReaderAllocate(&read_local_xlog_page, NULL);
 		if (!xlogreader)
 			ereport(ERROR,
@@ -2732,6 +2733,7 @@ GetLoggedPreparedXactState(char const *gid)
 			FlushErrorState();
 		}
 		PG_END_TRY();
+		MemoryContextSwitchTo(memctx);
 		XLogReaderFree(xlogreader);
 	}