#
# Copyright (c) 2005 XenSource Ltd.
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of version 2.1 of the GNU Lesser General Public
# License as published by the Free Software Foundation.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#


# Gentoo doesn't have ifup/ifdown, so we define appropriate alternatives.

# Other platforms just use ifup / ifdown directly.

##
# preiftransfer
#
# @param $1 The current name for the physical device, which is also the name
#           that the virtual device will take once the physical device has
#           been renamed.

if ! which ifup >/dev/null 2>/dev/null
then
  preiftransfer()
  {
    true
  }
  ifup()
  {
    false
  }
  ifdown()
  {
    false
  }
else
  preiftransfer()
  {
    true
  }
fi


first_file()
{
  t="$1"
  shift
  for file in $@
  do
    if [ "$t" "$file" ]
    then
      echo "$file"
      return
    fi
  done
}

find_dhcpd_conf_file()
{
  first_file -f /etc/dhcp3/dhcpd.conf /etc/dhcpd.conf
}


find_dhcpd_init_file()
{
  first_file -x /etc/init.d/{dhcp3-server,dhcp,dhcpd}
}

find_dhcpd_arg_file()
{
  first_file -f /etc/sysconfig/dhcpd /etc/defaults/dhcp /etc/default/dhcp3-server
}

# configure interfaces which act as pure bridge ports:
_setup_bridge_port() {
    local dev="$1"
    local virtual="$2"

    # take interface down ...
    ip link set ${dev} down

    if [ $virtual -ne 0 ] ; then
        # Initialise a dummy MAC address. We choose the numerically
        # largest non-broadcast address to prevent the address getting
        # stolen by an Ethernet bridge for STP purposes.
        # (FE:FF:FF:FF:FF:FF)
        ip link set ${dev} address fe:ff:ff:ff:ff:ff || true
    fi

    # ... and configure it
    ip addr flush ${dev}
}

setup_physical_bridge_port() {
    _setup_bridge_port $1 0
}
setup_virtual_bridge_port() {
    _setup_bridge_port $1 1
}

# Usage: create_bridge bridge
create_bridge () {
    local bridge=$1

    ovs-vsctl -- --may-exist add-br ${bridge}
}

# Usage: add_to_bridge bridge dev
add_to_bridge () {
    local bridge=$1
    local dev=$2

    # If the bridge is in format brX.Y, strip Y from the bridge
    # and use it as VLAN tag.
    if [[ $bridge =~ \.[[:digit:]]{1,4}$ ]]; then
        tag=$(echo ${bridge} | cut -d "." -f 2)
        bridge=$(echo ${bridge} | cut -d "." -f 1)
    fi

    if [ -z $tag ]; then
        ovs-vsctl -- --may-exist add-port ${bridge} ${dev}
    else
        ovs-vsctl -- --may-exist add-port ${bridge} ${dev} tag=${tag}
    fi

    ip link set ${dev} up
}

# Usage: delete_from_bridge bridge dev
delete_from_bridge () {
    local bridge=$1
    local dev=$2

    # If the bridge is in format brX.Y, strip Y from the bridge
    # and use it as VLAN tag.
    if [[ $bridge =~ \.[[:digit:]]{1,4}$ ]]; then
        tag=$(echo ${bridge} | cut -d "." -f 2)
        bridge=$(echo ${bridge} | cut -d "." -f 1)
    fi

    ovs-vsctl -- --if-exists del-port ${bridge} ${dev}
}