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, 12 insertions, 6 deletions

diff --git a/src/backend/utils/misc/superuser.c b/src/backend/utils/misc/superuser.c
index 1852b35e465..5139247291d 100644
--- a/src/backend/utils/misc/superuser.c
+++ b/src/backend/utils/misc/superuser.c
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/misc/superuser.c,v 1.15 2000/09/06 14:15:22 petere Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/misc/superuser.c,v 1.16 2000/11/16 22:30:40 tgl Exp $
  *
  * DESCRIPTION
  *	  See superuser().
@@ -29,10 +29,16 @@ superuser(void)
 	privileges.
 --------------------------------------------------------------------------*/
 	HeapTuple	utup;
+	bool		result;
 
-	utup = SearchSysCacheTuple(SHADOWSYSID,
-							   ObjectIdGetDatum(GetUserId()),
-							   0, 0, 0);
-	Assert(utup != NULL);
-	return ((Form_pg_shadow) GETSTRUCT(utup))->usesuper;
+	utup = SearchSysCache(SHADOWSYSID,
+						  ObjectIdGetDatum(GetUserId()),
+						  0, 0, 0);
+	if (HeapTupleIsValid(utup))
+	{
+		result = ((Form_pg_shadow) GETSTRUCT(utup))->usesuper;
+		ReleaseSysCache(utup);
+		return result;
+	}
+	return false;
 }