# vim: tabstop=4 shiftwidth=4 softtabstop=4

# Copyright 2010 United States Government as represented by the
# Administrator of the National Aeronautics and Space Administration.
# All Rights Reserved.
# Copyright 2012 Red Hat, Inc.
# Copyright 2013 NTT corp.
#
#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.

"""Command-line flag library.

Emulates gflags by wrapping cfg.ConfigOpts.

The idea is to move fully to cfg eventually, and this wrapper is a
stepping stone.

"""

import os
import socket

from oslo_config import cfg


CONF = cfg.CONF


def _get_my_ip():
    """
    Returns the actual ip of the local machine.

    This code figures out what source address would be used if some traffic
    were to be sent out to some well known address on the Internet. In this
    case, a Google DNS server is used, but the specific address does not
    matter much.  No traffic is actually sent.
    """
    try:
        csock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        csock.connect(('8.8.8.8', 80))
        (addr, port) = csock.getsockname()
        csock.close()
        return addr
    except socket.error:
        return "127.0.0.1"