copied from src/lib/libc/string/strnlen.c
Copyright (c) 2009 David Schultz <das@FreeBSD.org>

--- v4l2-compliance/v4l2-compliance.cpp.orig	2011-06-04 11:03:04.000000000 +0200
+++ v4l2-compliance/v4l2-compliance.cpp	2011-06-04 11:03:34.000000000 +0200
@@ -56,6 +56,18 @@ enum Option {
 	OptLast = 256
 };
 
+static size_t
+strnlen(const char *s, size_t maxlen)
+{
+        size_t len;
+ 
+        for (len = 0; len < maxlen; len++, s++) {
+                if (!*s)
+                        break;
+        }
+        return (len);
+}
+
 static char options[OptLast];
 
 static int app_result;
--- v4l2-compliance/v4l2-test-controls.cpp.orig	2011-06-04 11:12:52.000000000 +0200
+++ v4l2-compliance/v4l2-test-controls.cpp	2011-06-04 11:13:06.000000000 +0200
@@ -32,6 +32,18 @@
 #include <vector>
 #include "v4l2-compliance.h"
 
+static size_t
+strnlen(const char *s, size_t maxlen)
+{
+        size_t len;
+ 
+        for (len = 0; len < maxlen; len++, s++) {
+                if (!*s)
+                        break;
+        }
+        return (len);
+}
+
 static int checkQCtrl(struct node *node, struct test_queryctrl &qctrl)
 {
 	struct v4l2_querymenu qmenu;