From bdf9a9f9bd56354f70a7431a9682183b84353211 Mon Sep 17 00:00:00 2001
From: Piotr Caban <piotr@codeweavers.com>
Date: Fri, 7 Sep 2012 16:58:23 +0200
Subject: [PATCH] msvcrt: Fixed strncpy_s behavior when count equals 0.

---
 dlls/msvcrt/heap.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/dlls/msvcrt/heap.c b/dlls/msvcrt/heap.c
index 5eaf4a1c5eb..0a0d8193520 100644
--- a/dlls/msvcrt/heap.c
+++ b/dlls/msvcrt/heap.c
@@ -598,8 +598,11 @@ int CDECL strncpy_s(char *dest, MSVCRT_size_t numberOfElements,
 
     TRACE("(%s %lu %s %lu)\n", dest, numberOfElements, src, count);
 
-    if(!count)
+    if(!count) {
+        if(dest && numberOfElements)
+            *dest = 0;
         return 0;
+    }
 
     if (!MSVCRT_CHECK_PMT(dest != NULL)) return MSVCRT_EINVAL;
     if (!MSVCRT_CHECK_PMT(src != NULL)) return MSVCRT_EINVAL;