Fix signed vs unsigned issue with memcmp/strncmp where the size parameter

was incorrectly being treated as signed. ok miod@

2 files changed, 16 insertions, 10 deletions

diff --git a/lib/libc/arch/arm/string/memcmp.S b/lib/libc/arch/arm/string/memcmp.S
index 1c0045d4df2..866a31d1f8b 100644
--- a/lib/libc/arch/arm/string/memcmp.S
+++ b/lib/libc/arch/arm/string/memcmp.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: memcmp.S,v 1.2 2004/02/01 05:40:52 drahn Exp $	*/
+/*	$OpenBSD: memcmp.S,v 1.3 2009/05/03 05:09:40 drahn Exp $	*/
 /*      $NetBSD: memcmp.S,v 1.2 2003/04/05 23:08:52 bjh21 Exp $ */
 
 /*
@@ -34,10 +34,13 @@
 RCSID("$NetBSD: memcmp.S,v 1.2 2003/04/05 23:08:52 bjh21 Exp $")
 
 ENTRY(memcmp)
-/* if ((len - 1) < 0) return 0 */
-	subs	r2, r2, #1
-	movmi	r0, #0
-	movmi	pc, lr
+/* if (len == 0) return 0 */
+	cmp	r2, #0
+	moveq	r0, #0
+	moveq	pc, lr
+
+/* subtract one to have the index of the last character to check */
+	sub	r2, r2, #1
 
 /* ip == last src address to compare */
 	add	ip, r0, r2
diff --git a/lib/libc/arch/arm/string/strncmp.S b/lib/libc/arch/arm/string/strncmp.S
index 1473442ff14..f8960bbc84b 100644
--- a/lib/libc/arch/arm/string/strncmp.S
+++ b/lib/libc/arch/arm/string/strncmp.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: strncmp.S,v 1.3 2005/08/07 16:40:14 espie Exp $	*/
+/*	$OpenBSD: strncmp.S,v 1.4 2009/05/03 05:09:40 drahn Exp $	*/
 /*      $NetBSD: strncmp.S,v 1.2 2003/04/05 23:08:52 bjh21 Exp $ */
 
 /*
@@ -32,10 +32,13 @@
 #include <machine/asm.h>
 
 ENTRY(strncmp)
-/* if ((len - 1) < 0) return 0 */
-	subs	r2, r2, #1
-	movmi	r0, #0
-	movmi	pc, lr
+/* if (len == 0) return 0 */
+	cmp	r2, #0
+	moveq	r0, #0
+	moveq	pc, lr
+
+/* subtract one to have the index of the last character to check */
+	sub	r2, r2, #1
 
 /* ip == last src address to compare */
 	add	ip, r0, r2