From 31c1f1300e2f166061cb0a491fab30ac37018a94 Mon Sep 17 00:00:00 2001
From: Paul Sokolovsky <pfalcon@users.sourceforge.net>
Date: Sun, 25 Jan 2015 00:42:39 +0200
Subject: [PATCH] modffi: 's' (string) return type: handle NULL properly
 (return None).

---
 unix/modffi.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/unix/modffi.c b/unix/modffi.c
index 7c87e5b01a..6e0f06ec77 100644
--- a/unix/modffi.c
+++ b/unix/modffi.c
@@ -140,6 +140,9 @@ STATIC mp_obj_t return_ffi_value(ffi_arg val, char type)
     switch (type) {
         case 's': {
             const char *s = (const char *)val;
+            if (!s) {
+                return mp_const_none;
+            }
             return mp_obj_new_str(s, strlen(s), false);
         }
         case 'v':