From: Joe Conway <mail@joeconway.com>
Date: Sun, 1 Feb 2004 04:05:13 +0000 (+0000)
Subject: Fix text_position to not scan past end of source string in multibyte
X-Git-Tag: REL7_3_6~9
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=b59917f02e3ccb025d393b1e38acc935033f07fd;p=postgresql

Fix text_position to not scan past end of source string in multibyte
case, per report from Korea PostgreSQL Users' Group. Copied from Tom
Lane's 7.4 branch patch.
---

diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c
index 9c3faaf2a4..d4276ac101 100644
--- a/src/backend/utils/adt/varlena.c
+++ b/src/backend/utils/adt/varlena.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/varlena.c,v 1.92.2.2 2003/11/30 20:52:37 joe Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/varlena.c,v 1.92.2.3 2004/02/01 04:05:13 joe Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -665,9 +665,6 @@ text_position(Datum str, Datum search_str, int matchnum)
 	len1 = (VARSIZE(t1) - VARHDRSZ);
 	len2 = (VARSIZE(t2) - VARHDRSZ);
 
-	/* no use in searching str past point where search_str will fit */
-	px = (len1 - len2);
-
 	if (eml == 1)				/* simple case - single byte encoding */
 	{
 		char	   *p1,
@@ -676,6 +673,9 @@ text_position(Datum str, Datum search_str, int matchnum)
 		p1 = VARDATA(t1);
 		p2 = VARDATA(t2);
 
+		/* no use in searching str past point where search_str will fit */
+		px = (len1 - len2);
+
 		for (p = 0; p <= px; p++)
 		{
 			if ((*p2 == *p1) && (strncmp(p1, p2, len2) == 0))
@@ -703,6 +703,9 @@ text_position(Datum str, Datum search_str, int matchnum)
 		(void) pg_mb2wchar_with_len((unsigned char *) VARDATA(t2), p2, len2);
 		len2 = pg_wchar_strlen(p2);
 
+		/* no use in searching str past point where search_str will fit */
+		px = (len1 - len2);
+
 		for (p = 0; p <= px; p++)
 		{
 			if ((*p2 == *p1) && (pg_wchar_strncmp(p1, p2, len2) == 0))