msvcrt: Add _snprintf_s implementation.

dlls/msvcr100/msvcr100.spec

@@ -1044,7 +1044,7 @@
 @ stub _snprintf_c
 @ stub _snprintf_c_l
 @ stub _snprintf_l
-@ stub _snprintf_s
+@ varargs _snprintf_s(ptr long long str) msvcrt._snprintf_s
 @ stub _snprintf_s_l
 @ stub _snscanf
 @ stub _snscanf_l

dlls/msvcr80/msvcr80.spec

@@ -891,7 +891,7 @@
 @ stub _snprintf_c
 @ stub _snprintf_c_l
 @ stub _snprintf_l
-@ stub _snprintf_s
+@ varargs _snprintf_s(ptr long long str) msvcrt._snprintf_s
 @ stub _snprintf_s_l
 @ stub _snscanf
 @ stub _snscanf_l

dlls/msvcr90/msvcr90.spec

@@ -877,7 +877,7 @@
 @ stub _snprintf_c
 @ stub _snprintf_c_l
 @ stub _snprintf_l
-@ stub _snprintf_s
+@ varargs _snprintf_s(ptr long long str) msvcrt._snprintf_s
 @ stub _snprintf_s_l
 @ stub _snscanf
 @ stub _snscanf_l

dlls/msvcrt/msvcrt.spec

@@ -830,7 +830,7 @@
 # stub _snprintf_c
 # stub _snprintf_c_l
 # stub _snprintf_l
-# stub _snprintf_s
+@ varargs _snprintf_s(ptr long long str) MSVCRT__snprintf_s
 # stub _snprintf_s_l
 # stub _snscanf
 # stub _snscanf_l

dlls/msvcrt/wcs.c

@@ -1103,6 +1103,20 @@ int CDECL MSVCRT__snprintf(char *str, unsigned int len, const char *format, ...)
 }
 
 /*********************************************************************
+ *		_snprintf_s (MSVCRT.@)
+ */
+int CDECL MSVCRT__snprintf_s(char *str, unsigned int len, unsigned int count,
+    const char *format, ...)
+{
+    int retval;
+    __ms_va_list valist;
+    __ms_va_start(valist, format);
+    retval = MSVCRT_vsnprintf_s_l(str, len, count, format, NULL, valist);
+    __ms_va_end(valist);
+    return retval;
+}
+
+/*********************************************************************
  * vsnwprintf_internal (INTERNAL)
  */
 static inline int vsnwprintf_internal(MSVCRT_wchar_t *str, MSVCRT_size_t len,