EGameTools/DL2GameOverhaulScript/source/utils.cpp

#include "utils.h"
#include <Windows.h>

namespace Utils {
    WindowsVersion GetWindowsVersion() {
        OSVERSIONINFOEX info{};
        DWORDLONG dwlConditionMask = 0;

        // Initialize the OSVERSIONINFOEX structure.
        ZeroMemory(&info, sizeof(OSVERSIONINFOEX));
        info.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEX);
        info.dwMajorVersion = 6;

        // Initialize the condition mask.
        VER_SET_CONDITION(dwlConditionMask, VER_MAJORVERSION, VER_EQUAL);

        if (VerifyVersionInfo(&info, VER_MAJORVERSION, dwlConditionMask)) {
            // The major version is 6.
            info.dwMinorVersion = 1;
            VER_SET_CONDITION(dwlConditionMask, VER_MINORVERSION, VER_EQUAL);

            if (VerifyVersionInfo(&info, VER_MINORVERSION, dwlConditionMask))
                return WindowsVersion::Windows7;

            info.dwMinorVersion = 2;
            VER_SET_CONDITION(dwlConditionMask, VER_MINORVERSION, VER_EQUAL);

            if (VerifyVersionInfo(&info, VER_MINORVERSION, dwlConditionMask))
                return WindowsVersion::Windows10; // Windows 8 and 8.1 also use 6.2

            info.dwMinorVersion = 3;
            VER_SET_CONDITION(dwlConditionMask, VER_MINORVERSION, VER_EQUAL);

            if (VerifyVersionInfo(&info, VER_MINORVERSION, dwlConditionMask))
                return WindowsVersion::Windows10;
        } else {
            // The major version is not 6. Check if it's greater than 6.
            info.dwMajorVersion = 7;
            VER_SET_CONDITION(dwlConditionMask, VER_MAJORVERSION, VER_GREATER_EQUAL);

            if (VerifyVersionInfo(&info, VER_MAJORVERSION, dwlConditionMask))
                return WindowsVersion::Windows10;
        }

        return WindowsVersion::Unknown;
    }
}