--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/target-utils/libcommon/hexarg.c	Sat Jun 11 00:13:35 2016 +0000
@@ -0,0 +1,29 @@
+/*
+ * Many commands take hex arguments.  This module contains the parse_hexarg()
+ * function, which is a wrapper around strtoul that performs some additional
+ * checks.
+ */
+
+#include <sys/types.h>
+#include <ctype.h>
+#include <stdlib.h>
+
+parse_hexarg(arg, maxdigits, valp)
+	char *arg;
+	int maxdigits;
+	u_long *valp;
+{
+	char *cp = arg, *bp;
+	int len;
+
+	if (cp[0] == '0' && (cp[1] == 'x' || cp[1] == 'X'))
+		cp += 2;
+	for (bp = cp; *cp; cp++)
+		if (!isxdigit(*cp))
+			return(-1);
+	len = cp - bp;
+	if (len < 1 || len > maxdigits)
+		return(-1);
+	*valp = strtoul(arg, 0, 16);
+	return(0);
+}