Clean up handling of tuple descriptors so that result-tuple descriptors

allocated by plan nodes are not leaked at end of query.  This doesn't
really matter for normal queries, but it sure does for queries invoked
repetitively inside SQL functions.  Clean up some other grotty code
associated with tupdescs, and fix a few other memory leaks exposed by
tests with simple SQL functions.

1 files changed, 19 insertions, 44 deletions

diff --git a/src/backend/executor/functions.c b/src/backend/executor/functions.c
index 18a0e0cbb3b..575f33d84b6 100644
--- a/src/backend/executor/functions.c
+++ b/src/backend/executor/functions.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/executor/functions.c,v 1.42 2001/01/24 19:42:54 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/executor/functions.c,v 1.43 2001/01/29 00:39:19 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -24,7 +24,6 @@
 #include "tcop/tcopprot.h"
 #include "tcop/utility.h"
 #include "utils/builtins.h"
-#include "utils/datum.h"
 #include "utils/syscache.h"
 
 
@@ -73,7 +72,7 @@ typedef SQLFunctionCache *SQLFunctionCachePtr;
 static execution_state *init_execution_state(char *src,
 											 Oid *argOidVect, int nargs);
 static void init_sql_fcache(FmgrInfo *finfo);
-static TupleDesc postquel_start(execution_state *es);
+static void postquel_start(execution_state *es);
 static TupleTableSlot *postquel_getnext(execution_state *es);
 static void postquel_end(execution_state *es);
 static void postquel_sub_params(execution_state *es, FunctionCallInfo fcinfo);
@@ -82,24 +81,6 @@ static Datum postquel_execute(execution_state *es,
 							  SQLFunctionCachePtr fcache);
 
 
-static Datum
-ProjectAttribute(HeapTuple tup,
-				 AttrNumber	attrno,
-				 TupleDesc TD,
-				 bool *isnullP)
-{
-	Datum		val;
-
-	val = heap_getattr(tup, attrno, TD, isnullP);
-
-	if (*isnullP)
-		return val;
-
-	return datumCopy(val,
-					 TD->attrs[attrno - 1]->attbyval,
-					 TD->attrs[attrno - 1]->attlen);
-}
-
 static execution_state *
 init_execution_state(char *src, Oid *argOidVect, int nargs)
 {
@@ -240,18 +221,7 @@ init_sql_fcache(FmgrInfo *finfo)
 	 * allocated by the executor (i.e. slots and tuples) is freed.
 	 */
 	if (!finfo->fn_retset && !fcache->typbyval)
-	{
-		TupleTableSlot *slot;
-
-		slot = makeNode(TupleTableSlot);
-		slot->val = (HeapTuple) NULL;
-		slot->ttc_shouldFree = true;
-		slot->ttc_descIsNew = true;
-		slot->ttc_tupleDescriptor = (TupleDesc) NULL;
-		slot->ttc_buffer = InvalidBuffer;
-
-		fcache->funcSlot = slot;
-	}
+		fcache->funcSlot = MakeTupleTableSlot();
 	else
 		fcache->funcSlot = NULL;
 
@@ -289,7 +259,7 @@ init_sql_fcache(FmgrInfo *finfo)
 }
 
 
-static TupleDesc
+static void
 postquel_start(execution_state *es)
 {
 
@@ -298,8 +268,8 @@ postquel_start(execution_state *es)
 	 * 30-8-1996
 	 */
 	if (es->qd->operation == CMD_UTILITY)
-		return (TupleDesc) NULL;
-	return ExecutorStart(es->qd, es->estate);
+		return;
+	ExecutorStart(es->qd, es->estate);
 }
 
 static TupleTableSlot *
@@ -379,11 +349,11 @@ copy_function_result(SQLFunctionCachePtr fcache,
 	 * If first time through, we have to initialize the funcSlot's
 	 * tuple descriptor.
 	 */
-	if (TupIsNull(funcSlot))
+	if (funcSlot->ttc_tupleDescriptor == NULL)
 	{
-		resultTd = resultSlot->ttc_tupleDescriptor;
-		funcSlot->ttc_tupleDescriptor = CreateTupleDescCopy(resultTd);
-		funcSlot->ttc_descIsNew = true;
+		resultTd = CreateTupleDescCopy(resultSlot->ttc_tupleDescriptor);
+		ExecSetSlotDescriptor(funcSlot, resultTd, true);
+		ExecSetSlotDescriptorIsNew(funcSlot, true);
 	}
 
 	newTuple = heap_copytuple(resultTuple);
@@ -460,10 +430,15 @@ postquel_execute(execution_state *es,
 		}
 		else
 		{
-			value = ProjectAttribute(resSlot->val,
-									 1,
-									 resSlot->ttc_tupleDescriptor,
-									 &fcinfo->isnull);
+			value = heap_getattr(resSlot->val,
+								 1,
+								 resSlot->ttc_tupleDescriptor,
+								 &(fcinfo->isnull));
+			/*
+			 * Note: if result type is pass-by-reference then we are
+			 * returning a pointer into the tuple copied by
+			 * copy_function_result.  This is OK.
+			 */
 		}
 
 		/*