[MSVCRT_APITEST]

- add basic test for _vsnprintf
This is mostly to verify if WINE's implementation of _vcsprintf is correct

svn path=/trunk/; revision=56924

rostests/apitests/msvcrt/CMakeLists.txt

@@ -2,6 +2,7 @@
 add_definitions(-D_DLL -D__USE_CRTIMP)
 
 list(APPEND SOURCE
+    _vsnprintf.c
     ieee.c
     splitpath.c
     testlist.c)

rostests/apitests/msvcrt/_vsnprintf.c

@@ -0,0 +1,32 @@
+/*
+ * PROJECT:         ReactOS api tests
+ * LICENSE:         GPL - See COPYING in the top level directory
+ * PURPOSE:         Test for _vsnprintf
+ */
+
+#include <wine/test.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <strings.h>
+#include <stdarg.h>
+
+void call_varargs(char* buf, size_t buf_size, int expected_ret, LPCSTR formatString, ...)
+{
+    va_list args;
+    int ret;
+    /* Test the basic functionality */
+    va_start(args, formatString);
+    ret = _vsnprintf(buf, 255, formatString, args);
+    ok(expected_ret == ret, "Test failed: expected %i, got %i.\n", expected_ret, ret);
+}
+
+START_TEST(_vsnprintf)
+{
+    char buffer[255];
+    /* Test basic functionality */
+    call_varargs(buffer, 255, 12, "%s world!", "hello");
+    /* This is how WINE implements _vcsprintf, and they are obviously wrong */
+    call_varargs(NULL, INT_MAX, -1, "%s it really work?", "does");
+    /* This one is no better */
+    call_varargs(NULL, 0, -1, "%s it really work?", "does");
+}

rostests/apitests/msvcrt/testlist.c

@@ -5,11 +5,13 @@
 #define STANDALONE
 #include "wine/test.h"
 
+extern void func__vsnprintf(void);
 extern void func_ieee(void);
 extern void func_splitpath(void);
 
 const struct test winetest_testlist[] =
 {
+    { "_vsnprintf", func__vsnprintf},
     { "ieee", func_ieee },
     { "splitpath", func_splitpath },