1/*
2 * Copyright (C) 2009 Apple Inc. All Rights Reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include <windows.h>
27
28#if _WIN32_WINNT_WINBLUE
29#include <versionhelpers.h>
30#endif
31
32namespace rx {
33
34#ifndef _WIN32_WINNT_WINBLUE
35static bool IsWindowsVistaOrGreater()
36{
37    OSVERSIONINFOEXW osvi = { };
38    osvi.dwOSVersionInfoSize = sizeof(osvi);
39    osvi.dwMajorVersion = HIBYTE(_WIN32_WINNT_VISTA);
40    osvi.dwMinorVersion = LOBYTE(_WIN32_WINNT_VISTA);
41    DWORDLONG condition = 0;
42    VER_SET_CONDITION(condition, VER_MAJORVERSION, VER_GREATER_EQUAL);
43    VER_SET_CONDITION(condition, VER_MINORVERSION, VER_GREATER_EQUAL);
44    return !!::VerifyVersionInfoW(&osvi, VER_MAJORVERSION | VER_MINORVERSION, condition);
45}
46#endif
47
48bool isWindowsVistaOrGreater()
49{
50    static bool initialized = false;
51    static bool cachedIsWindowsVistaOrGreater;
52
53    if (!initialized) {
54        initialized = true;
55        cachedIsWindowsVistaOrGreater = IsWindowsVistaOrGreater();
56    }
57    return cachedIsWindowsVistaOrGreater;
58}
59
60} // namespace rx
61