Add a SPI_copytupledesc function that parallels SPI_copytuple --- ie,

it copies the tupdesc into upper-executor memory.  This is necessary
for returning tuple descriptors without leaking all of lower exec memory.

2 files changed, 43 insertions, 14 deletions

diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index 7b4030d580a..8c6420ae4cc 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/executor/spi.c,v 1.56 2001/08/02 16:05:23 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/executor/spi.c,v 1.57 2001/08/02 18:08:43 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -333,6 +333,33 @@ SPI_copytuple(HeapTuple tuple)
 	return ctuple;
 }
 
+TupleDesc
+SPI_copytupledesc(TupleDesc tupdesc)
+{
+	MemoryContext oldcxt = NULL;
+	TupleDesc	ctupdesc;
+
+	if (tupdesc == NULL)
+	{
+		SPI_result = SPI_ERROR_ARGUMENT;
+		return NULL;
+	}
+
+	if (_SPI_curid + 1 == _SPI_connected)		/* connected */
+	{
+		if (_SPI_current != &(_SPI_stack[_SPI_curid + 1]))
+			elog(FATAL, "SPI: stack corrupted");
+		oldcxt = MemoryContextSwitchTo(_SPI_current->savedcxt);
+	}
+
+	ctupdesc = CreateTupleDescCopy(tupdesc);
+
+	if (oldcxt)
+		MemoryContextSwitchTo(oldcxt);
+
+	return ctupdesc;
+}
+
 HeapTuple
 SPI_modifytuple(Relation rel, HeapTuple tuple, int natts, int *attnum,
 				Datum *Values, char *Nulls)
@@ -1232,7 +1259,7 @@ _SPI_end_call(bool procmem)
 }
 
 static bool
-_SPI_checktuples()
+_SPI_checktuples(void)
 {
 	uint32		processed = _SPI_current->processed;
 	SPITupleTable *tuptable = _SPI_current->tuptable;
@@ -1244,8 +1271,8 @@ _SPI_checktuples()
 			failed = true;
 	}
 	else
-/* some tuples were processed */
 	{
+		/* some tuples were processed */
 		if (tuptable == NULL)	/* spi_printtup was not called */
 			failed = true;
 		else if (processed != (tuptable->alloced - tuptable->free))
diff --git a/src/include/executor/spi.h b/src/include/executor/spi.h
index 3a7c7807942..bef68bc7a6e 100644
--- a/src/include/executor/spi.h
+++ b/src/include/executor/spi.h
@@ -2,6 +2,7 @@
  *
  * spi.h
  *
+ * $Id: spi.h,v 1.28 2001/08/02 18:08:43 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -48,17 +49,17 @@ typedef struct
 	HeapTuple  *vals;			/* tuples */
 } SPITupleTable;
 
-#define SPI_ERROR_CONNECT		-1
-#define SPI_ERROR_COPY			-2
-#define SPI_ERROR_OPUNKNOWN		-3
-#define SPI_ERROR_UNCONNECTED	-4
-#define SPI_ERROR_CURSOR		-5
-#define SPI_ERROR_ARGUMENT		-6
-#define SPI_ERROR_PARAM			-7
-#define SPI_ERROR_TRANSACTION	-8
-#define SPI_ERROR_NOATTRIBUTE	-9
-#define SPI_ERROR_NOOUTFUNC		-10
-#define SPI_ERROR_TYPUNKNOWN	-11
+#define SPI_ERROR_CONNECT		(-1)
+#define SPI_ERROR_COPY			(-2)
+#define SPI_ERROR_OPUNKNOWN		(-3)
+#define SPI_ERROR_UNCONNECTED	(-4)
+#define SPI_ERROR_CURSOR		(-5)
+#define SPI_ERROR_ARGUMENT		(-6)
+#define SPI_ERROR_PARAM			(-7)
+#define SPI_ERROR_TRANSACTION	(-8)
+#define SPI_ERROR_NOATTRIBUTE	(-9)
+#define SPI_ERROR_NOOUTFUNC		(-10)
+#define SPI_ERROR_TYPUNKNOWN	(-11)
 
 #define SPI_OK_CONNECT			1
 #define SPI_OK_FINISH			2
@@ -87,6 +88,7 @@ extern void *SPI_saveplan(void *plan);
 extern int  SPI_freeplan(void *plan);
 
 extern HeapTuple SPI_copytuple(HeapTuple tuple);
+extern TupleDesc SPI_copytupledesc(TupleDesc tupdesc);
 extern HeapTuple SPI_modifytuple(Relation rel, HeapTuple tuple, int natts,
 				int *attnum, Datum *Values, char *Nulls);
 extern int	SPI_fnumber(TupleDesc tupdesc, char *fname);