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, 24 insertions, 1 deletions

diff --git a/src/backend/nodes/makefuncs.c b/src/backend/nodes/makefuncs.c
index 45e1c03738c..95bf730963f 100644
--- a/src/backend/nodes/makefuncs.c
+++ b/src/backend/nodes/makefuncs.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/nodes/makefuncs.c,v 1.22 2000/08/08 15:41:24 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/nodes/makefuncs.c,v 1.23 2000/11/16 22:30:23 tgl Exp $
  *
  * NOTES
  *	  Creator functions in POSTGRES 4.2 are generated automatically. Most of
@@ -20,7 +20,10 @@
  *	  Andrew Yu			Oct 20, 1994	file creation
  */
 #include "postgres.h"
+
 #include "nodes/makefuncs.h"
+#include "utils/lsyscache.h"
+
 
 /*
  * makeOper -
@@ -144,6 +147,26 @@ makeConst(Oid consttype,
 }
 
 /*
+ * makeNullConst -
+ *	  creates a Const node representing a NULL of the specified type
+ */
+Const *
+makeNullConst(Oid consttype)
+{
+	int16		typLen;
+	bool		typByVal;
+
+	get_typlenbyval(consttype, &typLen, &typByVal);
+	return makeConst(consttype,
+					 (int) typLen,
+					 (Datum) 0,
+					 true,
+					 typByVal,
+					 false,
+					 false);
+}
+
+/*
  * makeAttr -
  *	  creates an Attr node
  */