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  #   Eˆl–äY>”*a,jvàApN©‹FÿÛ„e§ŸÄÙ ?÷     E# Copyright (C) 2013-2014 Canonical Ltd.
#
# Author: Scott Moser <scott.moser@canonical.com>
# Author: Blake Rouse <blake.rouse@canonical.com>
#
# This file is part of cloud-init. See LICENSE file for license information.

import errno
import logging
import os
import re
from functools import partial

from cloudinit.net.network_state import mask_to_net_prefix
from cloudinit import util
from cloudinit.url_helper import UrlError, readurl

LOG = logging.getLogger(__name__)
SYS_CLASS_NET = "/sys/class/net/"
DEFAULT_PRIMARY_INTERFACE = 'eth0'


def natural_sort_key(s, _nsre=re.compile('([0-9]+)')):
    """Sorting for Humans: natural sort order. Can be use as the key to sort
    functions.
    This will sort ['eth0', 'ens3', 'ens10', 'ens12', 'ens8', 'ens0'] as
    ['ens0', 'ens3', 'ens8', 'ens10', 'ens12', 'eth0'] instead of the simple
    python way which will produce ['ens0', 'ens10', 'ens12', 'ens3', 'ens8',
    'eth0']."""
    return [int(text) if text.isdigit() else text.lower()
            for text in re.split(_nsre, s)]


def get_sys_class_path():
    """Simple function to return the global SYS_CLASS_NET."""
    return SYS_CLASS_NET


def sys_dev_path(devname, path=""):
    return get_sys_class_path() + devname + "/" + path


def read_sys_net(devname, path, translate=None,
                 on_enoent=None, on_keyerror=None,
                 on_einval=None):
    dev_path = sys_dev_path(devname, path)
    try:
        contents = util.load_file(dev_path)
    except (OSError, IOError) as e:
        e_errno = getattr(e, 'errno', None)
        if e_errno in (errno.ENOENT, errno.ENOTDIR):
            if on_enoent is not None:
                return on_enoent(e)
        if e_errno in (errno.EINVAL,):
            if on_einval is not None:
                return on_einval(e)
        raise
    contents = contents.strip()
    if translate is None:
        return contents
    try:
        return translate[contents]
    except KeyError as e:
        if on_keyerror is not None:
            return on_keyerror(e)
        else:
            LOG.debug("Found unexpected (not translatable) value"
                      " '%s' in '%s", contents, dev_path)
            raise


def read_sys_net_safe(iface, field, translate=None):
    def on_excp_false(e):
        return False
    return read_sys_net(iface, field,
                        on_keyerror=on_excp_false,
                        on_enoent=on_excp_false,
                        on_einval=on_excp_false,
                        translate=translate)


def read_sys_net_int(iface, field):
    val = read_sys_net_safe(iface, field)
    if val is False:
        return None
    try:
        return int(val)
    except ValueError:
        return None


def is_up(devname):
    # The linux kernel says to consider devices in 'unknown'
    # operstate as up for the purposes of network configuration. See
    # Documentation/networking/operstates.txt in the kernel source.
    translate = {'up': True, 'unknown': True, 'down': False}
    return read_sys_net_safe(devname, "operstate", translate=translate)


def is_wireless(devname):
    return os.path.exists(sys_dev_path(devname, "wireless"))


def is_bridge(devname):
    return os.path.exists(sys_dev_path(devname, "bridge"))


def is_bond(devname):
    return os.path.exists(sys_dev_path(devname, "bonding"))


def get_master(devname):
    """Return the master path for devname, or None if no master"""
    path = sys_dev_path(devname, path="master")
    if os.path.exists(path):
        return path
    return None


def master_is_bridge_or_bond(devname):
    """Return a bool indicating if devname's master is a bridge or bond"""
    master_path = get_master(devname)
    if master_path is None:
        return False
    bonding_path = os.path.join(master_path, "bonding")
    bridge_path = os.path.join(master_path, "bridge")
    return (os.path.exists(bonding_path) or os.path.exists(bridge_path))


def is_netfailover(devname, driver=None):
    """ netfailover driver uses 3 nics, master, primary and standby.