wversion.cpp

Go to the documentation of this file.

/* Copyright (c) 2010 Wildfire Games
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#include "precompiled.h"
#include "lib/sysdep/os/win/wversion.h"

#include "lib/sysdep/os/win/win.h"
#include "lib/sysdep/os/win/winit.h"

WINIT_REGISTER_EARLY_INIT(wversion_Init);


static wchar_t windowsVersionString[20];
static size_t windowsVersion;   // see WVERSION_*


const wchar_t* wversion_Family()
{
    ENSURE(windowsVersion != 0);
    switch(windowsVersion)
    {
    case WVERSION_2K:
        return L"Win2k";
    case WVERSION_XP:
        return L"WinXP";
    case WVERSION_XP64:
        return L"WinXP64";
    case WVERSION_VISTA:
        return L"Vista";
    case WVERSION_7:
        return L"Win7";
    case WVERSION_8:
        return L"Win8";
    default:
        return L"Windows";
    }
}


const wchar_t* wversion_String()
{
    ENSURE(windowsVersionString[0] != '\0');
    return windowsVersionString;
}

size_t wversion_Number()
{
    ENSURE(windowsVersion != 0);
    return windowsVersion;
}


static Status wversion_Init()
{
    // note: don't use GetVersion[Ex] because it gives the version of the
    // emulated OS when running an app with compatibility shims enabled.
    HKEY hKey;
    if(RegOpenKeyExW(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion", 0, KEY_QUERY_VALUE, &hKey) == ERROR_SUCCESS)
    {
        DWORD size = sizeof(windowsVersionString);
        (void)RegQueryValueExW(hKey, L"CurrentVersion", 0, 0, (LPBYTE)windowsVersionString, &size);

        unsigned major = 0, minor = 0;
        // ICC 11.1.082 generates incorrect code for the following:
        // const int ret = swscanf_s(windowsVersionString, L"%u.%u", &major, &minor);
        std::wstringstream ss(windowsVersionString);
        ss >> major;
        wchar_t dot;
        ss >> dot;
        ENSURE(dot == '.');
        ss >> minor;

        ENSURE(4 <= major && major <= 0xFF);
        ENSURE(minor <= 0xFF);
        windowsVersion = (major << 8) | minor;

        RegCloseKey(hKey);
    }
    else
        DEBUG_WARN_ERR(ERR::LOGIC);

    return INFO::OK;
}