Add strnlen() to libkern.

ok deraadt

3 files changed, 40 insertions, 2 deletions

diff --git a/sys/conf/files b/sys/conf/files
index c9f64518be5..3878a6926b3 100644
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -1,4 +1,4 @@
-#	$OpenBSD: files,v 1.536 2012/04/06 15:10:40 jsing Exp $
+#	$OpenBSD: files,v 1.537 2012/04/26 01:22:31 matthew Exp $
 #	$NetBSD: files,v 1.87 1996/05/19 17:17:50 jonathan Exp $
 
 #	@(#)files.newconf	7.5 (Berkeley) 5/10/93
@@ -1034,6 +1034,7 @@ file lib/libkern/arch/${MACHINE_ARCH}/strlcpy.S | lib/libkern/strlcpy.c
 file lib/libkern/arch/${MACHINE_ARCH}/strlen.S | lib/libkern/strlen.c
 file lib/libkern/arch/${MACHINE_ARCH}/strncmp.S | lib/libkern/strncmp.c
 file lib/libkern/arch/${MACHINE_ARCH}/strncpy.S | lib/libkern/strncpy.c
+file lib/libkern/arch/${MACHINE_ARCH}/strnlen.S | lib/libkern/strnlen.c
 file lib/libkern/arch/${MACHINE_ARCH}/scanc.S | lib/libkern/scanc.c
 file lib/libkern/arch/${MACHINE_ARCH}/skpc.S | lib/libkern/skpc.c
 file lib/libkern/arch/${MACHINE_ARCH}/htonl.S | lib/libkern/htonl.c
diff --git a/sys/lib/libkern/libkern.h b/sys/lib/libkern/libkern.h
index c9545cd33ea..a2e6efccd3f 100644
--- a/sys/lib/libkern/libkern.h
+++ b/sys/lib/libkern/libkern.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: libkern.h,v 1.28 2011/01/10 23:23:56 tedu Exp $	*/
+/*	$OpenBSD: libkern.h,v 1.29 2012/04/26 01:22:31 matthew Exp $	*/
 /*	$NetBSD: libkern.h,v 1.7 1996/03/14 18:52:08 christos Exp $	*/
 
 /*-
@@ -154,6 +154,7 @@ int	 skpc(int, size_t, u_char *);
 size_t	 strlen(const char *);
 char	*strncpy(char *, const char *, size_t)
 		__attribute__ ((__bounded__(__string__,1,3)));
+size_t	 strnlen(const char *, size_t);
 size_t	 strlcpy(char *, const char *, size_t)
 		__attribute__ ((__bounded__(__string__,1,3)));
 size_t	 strlcat(char *, const char *, size_t)
diff --git a/sys/lib/libkern/strnlen.c b/sys/lib/libkern/strnlen.c
new file mode 100644
index 00000000000..ac439d066a2
--- /dev/null
+++ b/sys/lib/libkern/strnlen.c
@@ -0,0 +1,36 @@
+/*	$OpenBSD: strnlen.c,v 1.1 2012/04/26 01:22:31 matthew Exp $	*/
+
+/*
+ * Copyright (c) 2010 Todd C. Miller <Todd.Miller@courtesan.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+
+#if !defined(_KERNEL) && !defined(_STANDALONE)
+#include <string.h>
+#else
+#include <lib/libkern/libkern.h>
+#endif
+
+size_t
+strnlen(const char *str, size_t maxlen)
+{
+	const char *cp;
+
+	for (cp = str; maxlen != 0 && *cp != '\0'; cp++, maxlen--)
+		;
+
+	return (size_t)(cp - str);
+}