msvcrt: Implemented vswprintf_s.

dlls/msvcrt/msvcrt.spec

@@ -760,6 +760,7 @@
 @ cdecl vprintf(str ptr) MSVCRT_vprintf
 @ cdecl vsprintf(ptr str ptr) MSVCRT_vsprintf
 @ cdecl vswprintf(ptr wstr ptr) MSVCRT_vswprintf
+@ cdecl vswprintf_s(ptr long wstr ptr) MSVCRT_vswprintf_s
 @ cdecl vwprintf(wstr ptr) MSVCRT_vwprintf
 @ cdecl wcscat(wstr wstr) ntdll.wcscat
 @ cdecl wcscat_s(wstr long wstr) MSVCRT_wcscat_s

dlls/msvcrt/wcs.c

@@ -657,6 +657,11 @@ static int pf_vsnprintf( pf_output *out, const WCHAR *format, va_list valist )
         flags.Format = *p;
         r = 0;
 
+        if (flags.Format == '$')
+        {
+            FIXME("Positional parameters are not supported (%s)\n", wine_dbgstr_w(format));
+            return -1;
+        }
         /* output a string */
         if(  flags.Format == 's' || flags.Format == 'S' )
             r = pf_handle_string_format( out, va_arg(valist, const void*), -1,
@@ -876,6 +881,15 @@ int CDECL MSVCRT_vswprintf( MSVCRT_wchar_t* str, const MSVCRT_wchar_t* format, v
 }
 
 /*********************************************************************
+ *		vswprintf_s (MSVCRT.@)
+ */
+int CDECL MSVCRT_vswprintf_s( MSVCRT_wchar_t* str, MSVCRT_size_t num, const MSVCRT_wchar_t* format, va_list args )
+{
+    /* FIXME: must handle positional arguments */
+    return MSVCRT_vsnwprintf( str, num, format, args );
+}
+
+/*********************************************************************
  *		wcscoll (MSVCRT.@)
  */
 int CDECL MSVCRT_wcscoll( const MSVCRT_wchar_t* str1, const MSVCRT_wchar_t* str2 )