resolver.py 文件源码

def _win32_is_nic_enabled(self, lm, guid, interface_key):
        # Look in the Windows Registry to determine whether the network
        # interface corresponding to the given guid is enabled.
        #
        # (Code contributed by Paul Marks, thanks!)
        #
        try:
            # This hard-coded location seems to be consistent, at least
            # from Windows 2000 through Vista.
            connection_key = _winreg.OpenKey(
                lm,
                r'SYSTEM\CurrentControlSet\Control\Network'
                r'\{4D36E972-E325-11CE-BFC1-08002BE10318}'
                r'\%s\Connection' % guid)

            try:
                # The PnpInstanceID points to a key inside Enum
                (pnp_id, ttype) = _winreg.QueryValueEx(
                    connection_key, 'PnpInstanceID')

                if ttype != _winreg.REG_SZ:
                    raise ValueError

                device_key = _winreg.OpenKey(
                    lm, r'SYSTEM\CurrentControlSet\Enum\%s' % pnp_id)

                try:
                    # Get ConfigFlags for this device
                    (flags, ttype) = _winreg.QueryValueEx(
                        device_key, 'ConfigFlags')

                    if ttype != _winreg.REG_DWORD:
                        raise ValueError

                    # Based on experimentation, bit 0x1 indicates that the
                    # device is disabled.
                    return not (flags & 0x1)

                finally:
                    device_key.Close()
            finally:
                connection_key.Close()
        except (EnvironmentError, ValueError):
            # Pre-vista, enabled interfaces seem to have a non-empty
            # NTEContextList; this was how dnspython detected enabled
            # nics before the code above was contributed.  We've retained
            # the old method since we don't know if the code above works
            # on Windows 95/98/ME.
            try:
                (nte, ttype) = _winreg.QueryValueEx(interface_key,
                                                    'NTEContextList')
                return nte is not None
            except WindowsError:
                return False