1 files changed, 25 insertions, 7 deletions

diff --git a/tools/lib/string.c b/tools/lib/string.c
index bd239bc1d557..a4246f14ded1 100644
--- a/tools/lib/string.c
+++ b/tools/lib/string.c
@@ -39,27 +39,45 @@ void *memdup(const void *src, size_t len)
  * @s: input string
  * @res: result
  *
- * This routine returns 0 iff the first character is one of 'Yy1Nn0'.
- * Otherwise it will return -EINVAL.  Value pointed to by res is
- * updated upon finding a match.
+ * This routine returns 0 iff the first character is one of 'Yy1Nn0', or
+ * [oO][NnFf] for "on" and "off". Otherwise it will return -EINVAL.  Value
+ * pointed to by res is updated upon finding a match.
  */
 int strtobool(const char *s, bool *res)
 {
+        if (!s)
+                return -EINVAL;
+
         switch (s[0]) {
         case 'y':
         case 'Y':
         case '1':
                 *res = true;
-                break;
+                return 0;
         case 'n':
         case 'N':
         case '0':
                 *res = false;
-                break;
+                return 0;
+        case 'o':
+        case 'O':
+                switch (s[1]) {
+                case 'n':
+                case 'N':
+                        *res = true;
+                        return 0;
+                case 'f':
+                case 'F':
+                        *res = false;
+                        return 0;
+                default:
+                        break;
+                }
         default:
-                return -EINVAL;
+                break;
         }
-        return 0;
+
+        return -EINVAL;
 }
 
 /**