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, 20 insertions, 21 deletions

diff --git a/src/backend/executor/nodeAgg.c b/src/backend/executor/nodeAgg.c
index fae1a5b0d87..827001384f6 100644
--- a/src/backend/executor/nodeAgg.c
+++ b/src/backend/executor/nodeAgg.c
@@ -34,7 +34,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/executor/nodeAgg.c,v 1.71 2000/08/24 03:29:03 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/executor/nodeAgg.c,v 1.72 2000/11/16 22:30:22 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -51,6 +51,7 @@
 #include "parser/parse_expr.h"
 #include "parser/parse_oper.h"
 #include "parser/parse_type.h"
+#include "utils/lsyscache.h"
 #include "utils/syscache.h"
 #include "utils/tuplesort.h"
 #include "utils/datum.h"
@@ -105,7 +106,7 @@ typedef struct AggStatePerAggData
 	 * We need the len and byval info for the agg's input, result, and
 	 * transition data types in order to know how to copy/delete values.
 	 */
-	int			inputtypeLen,
+	int16		inputtypeLen,
 				resulttypeLen,
 				transtypeLen;
 	bool		inputtypeByVal,
@@ -827,7 +828,6 @@ ExecInitAgg(Agg *node, EState *estate, Plan *parent)
 		char	   *aggname = aggref->aggname;
 		HeapTuple	aggTuple;
 		Form_pg_aggregate aggform;
-		Type		typeInfo;
 		Oid			transfn_oid,
 					finalfn_oid;
 
@@ -837,23 +837,23 @@ ExecInitAgg(Agg *node, EState *estate, Plan *parent)
 		/* Fill in the peraggstate data */
 		peraggstate->aggref = aggref;
 
-		aggTuple = SearchSysCacheTupleCopy(AGGNAME,
-										   PointerGetDatum(aggname),
-										   ObjectIdGetDatum(aggref->basetype),
-										   0, 0);
+		aggTuple = SearchSysCache(AGGNAME,
+								  PointerGetDatum(aggname),
+								  ObjectIdGetDatum(aggref->basetype),
+								  0, 0);
 		if (!HeapTupleIsValid(aggTuple))
 			elog(ERROR, "ExecAgg: cache lookup failed for aggregate %s(%s)",
 				 aggname,
-				 typeidTypeName(aggref->basetype));
+				 aggref->basetype ?
+				 typeidTypeName(aggref->basetype) : (char *) "");
 		aggform = (Form_pg_aggregate) GETSTRUCT(aggTuple);
 
-		typeInfo = typeidType(aggform->aggfinaltype);
-		peraggstate->resulttypeLen = typeLen(typeInfo);
-		peraggstate->resulttypeByVal = typeByVal(typeInfo);
-
-		typeInfo = typeidType(aggform->aggtranstype);
-		peraggstate->transtypeLen = typeLen(typeInfo);
-		peraggstate->transtypeByVal = typeByVal(typeInfo);
+		get_typlenbyval(aggform->aggfinaltype,
+						&peraggstate->resulttypeLen,
+						&peraggstate->resulttypeByVal);
+		get_typlenbyval(aggform->aggtranstype,
+						&peraggstate->transtypeLen,
+						&peraggstate->transtypeByVal);
 
 		peraggstate->initValue =
 			AggNameGetInitVal(aggname,
@@ -901,23 +901,22 @@ ExecInitAgg(Agg *node, EState *estate, Plan *parent)
 			Form_pg_operator pgopform;
 
 			peraggstate->inputType = inputType;
-			typeInfo = typeidType(inputType);
-			peraggstate->inputtypeLen = typeLen(typeInfo);
-			peraggstate->inputtypeByVal = typeByVal(typeInfo);
+			get_typlenbyval(inputType,
+							&peraggstate->inputtypeLen,
+							&peraggstate->inputtypeByVal);
 
 			eq_operator = oper("=", inputType, inputType, true);
 			if (!HeapTupleIsValid(eq_operator))
-			{
 				elog(ERROR, "Unable to identify an equality operator for type '%s'",
 					 typeidTypeName(inputType));
-			}
 			pgopform = (Form_pg_operator) GETSTRUCT(eq_operator);
 			fmgr_info(pgopform->oprcode, &(peraggstate->equalfn));
+			ReleaseSysCache(eq_operator);
 			peraggstate->sortOperator = any_ordering_op(inputType);
 			peraggstate->sortstate = NULL;
 		}
 
-		heap_freetuple(aggTuple);
+		ReleaseSysCache(aggTuple);
 	}
 
 	return TRUE;