rev 401 - trunk

Author: giles
Date: 2005-05-02 13:49:28 -0700 (Mon, 02 May 2005)
New Revision: 401

Modified:
   trunk/memcmp.c
Log:
Alter our portability fallback implementation of memcmp() to properly ret=
urn
negative values is the first argument is "less than" the second. The prev=
ious
one was fine for our purposes, but could cause problems if it was acciden=
tally
used by client applications.

Thanks to Ray Johnston for pointing this out.


Modified: trunk/memcmp.c
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
--- trunk/memcmp.c	2005-04-28 04:44:30 UTC (rev 400)
+++ trunk/memcmp.c	2005-05-02 20:49:28 UTC (rev 401)
@@ -1,7 +1,7 @@
 /*
     jbig2dec
    =20
-    Copyright (C) 2001-2002 artofcode LLC.
+    Copyright (C) 2001-2005 artofcode LLC.
    =20
     This software is distributed under license and may not
     be copied, modified or distributed except as expressly
@@ -13,7 +13,7 @@
     Artifex Software, Inc.,  101 Lucas Valley Road #110,
     San Rafael, CA  94903, U.S.A., +1(415)492-9861.
=20
-    $Id: memcmp.c,v 1.1 2002/08/05 17:10:44 giles Exp $
+    $Id$
 */
=20
 #ifdef HAVE_CONFIG_H
@@ -26,24 +26,27 @@
=20
 /*
  * compares two byte strings 'a' and 'b', both assumed to be 'len' bytes=
 long
- * returns zero if the two strings are identical, otherwise returns the =
difference
- * between the values of the first two differing bytes, considered as un=
signed chars
+ * returns zero if the two strings are identical, otherwise returns -1 o=
r 1
+ * depending on the relative magnitude of the first differing elements,
+ * considered as unsigned chars
  */
=20
 int memcmp(const void *b1, const void *b2, size_t len)
 {
 	unsigned char *a, *b;
-	unsigned char c;
 	size_t i;
=20
 	a =3D (unsigned char *)b1;
 	b =3D (unsigned char *)b2;
 	for(i =3D 0; i < len; i++) {
-		c =3D *a - *b;
-		if (c) return (int)c; /* strings differ */
+		if (*a !=3D *b) {
+			 /* strings differ */
+			return (*a < *b) ? -1 : 1;
+		}
 		a++;
 		b++;
 	}
=20
-	return 0; /* strings match */
+	/* strings match */
+	return 0;
 }