Change SearchSysCache coding conventions so that a reference count is

maintained for each cache entry.  A cache entry will not be freed until
the matching ReleaseSysCache call has been executed.  This eliminates
worries about cache entries getting dropped while still in use.  See
my posting to pg-hackers of even date for more info.

1 files changed, 8 insertions, 11 deletions

diff --git a/src/backend/rewrite/rewriteSupport.c b/src/backend/rewrite/rewriteSupport.c
index 264021da223..30e4ba6e603 100644
--- a/src/backend/rewrite/rewriteSupport.c
+++ b/src/backend/rewrite/rewriteSupport.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteSupport.c,v 1.44 2000/09/29 18:21:24 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteSupport.c,v 1.45 2000/11/16 22:30:29 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -18,19 +18,15 @@
 #include "catalog/catname.h"
 #include "catalog/indexing.h"
 #include "rewrite/rewriteSupport.h"
-#include "utils/catcache.h"
 #include "utils/syscache.h"
 
 
-int
+bool
 IsDefinedRewriteRule(char *ruleName)
 {
-	HeapTuple	tuple;
-
-	tuple = SearchSysCacheTuple(RULENAME,
+	return SearchSysCacheExists(RULENAME,
 								PointerGetDatum(ruleName),
 								0, 0, 0);
-	return HeapTupleIsValid(tuple);
 }
 
 /*
@@ -59,10 +55,11 @@ SetRelationRuleStatus(Oid relationId, bool relHasRules,
 	 * Find the tuple to update in pg_class, using syscache for the lookup.
 	 */
 	relationRelation = heap_openr(RelationRelationName, RowExclusiveLock);
-	tuple = SearchSysCacheTupleCopy(RELOID,
-									ObjectIdGetDatum(relationId),
-									0, 0, 0);
-	Assert(HeapTupleIsValid(tuple));
+	tuple = SearchSysCacheCopy(RELOID,
+							   ObjectIdGetDatum(relationId),
+							   0, 0, 0);
+	if (!HeapTupleIsValid(tuple))
+		elog(ERROR, "SetRelationRuleStatus: cache lookup failed for relation %u", relationId);
 
 	/* Do the update */
 	((Form_pg_class) GETSTRUCT(tuple))->relhasrules = relHasRules;