From 1b81fd7793285d5651f5070b9b4161e10ade7846 Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Tue, 24 Aug 1999 00:09:56 +0000
Subject: [PATCH] coerce_type() failed to guard against trying to convert a
NULL constant to a different type. Not sure that this could happen in
ordinary parser usage, but it can in some new code I'm working on...
---
src/backend/parser/parse_coerce.c | 34 +++++++++++++++----------------
1 file changed, 17 insertions(+), 17 deletions(-)
diff --git a/src/backend/parser/parse_coerce.c b/src/backend/parser/parse_coerce.c
index 026c66168b..297337da4d 100644
--- a/src/backend/parser/parse_coerce.c
+++ b/src/backend/parser/parse_coerce.c
@@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/parser/parse_coerce.c,v 2.22 1999/08/05 02:33:53 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/parser/parse_coerce.c,v 2.23 1999/08/24 00:09:56 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -60,24 +60,24 @@ coerce_type(ParseState *pstate, Node *node, Oid inputTypeId, Oid targetTypeId,
* whereas float-to-int type conversion will round to integer.
*/
Const *con = (Const *) node;
+ Const *newcon = makeNode(Const);
Type targetType = typeidType(targetTypeId);
- char *val;
- /* We know the source constant is really of type 'text' */
- val = textout((text *) con->constvalue);
+ newcon->consttype = targetTypeId;
+ newcon->constlen = typeLen(targetType);
+ newcon->constbyval = typeByVal(targetType);
+ newcon->constisnull = con->constisnull;
+ newcon->constisset = false;
- /* now make a new const node */
- con = makeNode(Const);
- con->consttype = targetTypeId;
- con->constlen = typeLen(targetType);
- con->constvalue = stringTypeDatum(targetType, val, atttypmod);
- con->constisnull = false;
- con->constbyval = typeByVal(targetType);
- con->constisset = false;
+ if (! con->constisnull)
+ {
+ /* We know the source constant is really of type 'text' */
+ char *val = textout((text *) con->constvalue);
+ newcon->constvalue = stringTypeDatum(targetType, val, atttypmod);
+ pfree(val);
+ }
- pfree(val);
-
- result = (Node *) con;
+ result = (Node *) newcon;
}
else
{
@@ -105,7 +105,7 @@ coerce_type(ParseState *pstate, Node *node, Oid inputTypeId, Oid targetTypeId,
* such as coercing text 'now' to datetime? Need a way to
* know whether type conversion function is cacheable...
*/
- if (IsA(node, Const))
+ if (IsA(node, Const) && ! ((Const *) node)->constisnull)
{
Const *con = (Const *) node;
Oid convertFuncid;
@@ -122,9 +122,9 @@ coerce_type(ParseState *pstate, Node *node, Oid inputTypeId, Oid targetTypeId,
con = makeNode(Const);
con->consttype = targetTypeId;
con->constlen = typeLen(targetType);
+ con->constbyval = typeByVal(targetType);
con->constvalue = val;
con->constisnull = false;
- con->constbyval = typeByVal(targetType);
con->constisset = false;
result = (Node *) con;