Function IsWindowsVersionOrLater

ReClass/Utils.cpp:231–271

bool IsWindowsVersionOrLater( OSType target )
{
    DWORDLONG Mask = 0;
    RTL_OSVERSIONINFOEXW versionInfo;

    ZeroMemory( &versionInfo, sizeof( versionInfo ) );
    versionInfo.dwOSVersionInfoSize = sizeof( RTL_OSVERSIONINFOEXW );

	if (target == Windows10)
	{
		if (ntdll::RtlGetVersion && ntdll::RtlGetVersion( (PRTL_OSVERSIONINFOW)&versionInfo ) == 0)
			return (versionInfo.dwMajorVersion == 10);

		return false;
	}

	if (target >= WinVista)
	{
        versionInfo.dwMajorVersion = 6;

		switch (target)
		{
		case WinVista:  versionInfo.dwMinorVersion = 0; break;
		case Windows7:  versionInfo.dwMinorVersion = 1; break;
		case Windows8:  versionInfo.dwMinorVersion = 2; break;
		default: 
            break;
		}
	}
	else
	{
        versionInfo.dwMajorVersion = 5;
        versionInfo.dwMinorVersion = (target >= WinXP) ? 1 : 0;
	}

	VER_SET_CONDITION( Mask, VER_MAJORVERSION, VER_GREATER_EQUAL );
	VER_SET_CONDITION( Mask, VER_MINORVERSION, VER_GREATER_EQUAL );
	VER_SET_CONDITION( Mask, VER_SERVICEPACKMAJOR, VER_GREATER_EQUAL );
	VER_SET_CONDITION( Mask, VER_SERVICEPACKMINOR, VER_GREATER_EQUAL );
	return VerifyVersionInfoW( &versionInfo, VER_MAJORVERSION | VER_MINORVERSION | VER_SERVICEPACKMAJOR | VER_SERVICEPACKMINOR, Mask ) != FALSE;
}

OSType GetOperatingSystemType( )
{