#!/bin/sh

bridge_parse_ports()
{
  while [ x"${1+set}" = xset ]
  do
    # For compatibility: the `all' option.
    case $1 in
      all)
	shift &&
	set regex eth.\* em.\* en.\* 'p[0-9].*' noregex "$@"
	;;
    esac

    # Primitive state machine...
    case $1-`uname -s` in
      regex-Linux)
	all_interfaces=`sed -n 's%^[\ ]*\([^:]*\):.*$%\1%p' < /proc/net/dev`
	shift
	;;
      regex-*)
	echo -n "$0 needs to be ported for your `uname -s` system.  " >&2
	echo "Trying to continue nevertheless." >&2
	shift
	;;
      noregex-*)
	all_interfaces=
	unset all_interfaces
	shift
	;;
    esac

    case ${all_interfaces+regex}-${1+set} in
      regex-set)
	# The following interface specification are to be parsed as regular
	# expressions against all interfaces the system provides.
	i=`egrep "^$1$" << EOAI
$all_interfaces
EOAI
`
	shift
	;;
      *-set)
	# Literal interfaces.
	i=$1
	shift
	;;
      *)
	# No interface specification is following.
	i=
	;;
    esac

    echo $i
  done
}

create_vlan_port()
{
# port doesn't yet exist
if [ ! -e "/sys/class/net/$port" ]
then
  local dev="${port%.*}"
  # port is a vlan and the device exists?
  if [ "$port" != "$dev" ] && [ -e "/sys/class/net/$dev" ]
  then
    if [ -f /proc/sys/net/ipv6/conf/$dev/disable_ipv6 ]
    then
      echo 1 > /proc/sys/net/ipv6/conf/$dev/disable_ipv6
    fi
    ip link set "$dev" up
    ip link add link "$dev" name "$port" type vlan id "${port#*.}"
  fi
fi
}

destroy_vlan_port()
{
# port exists
if [ -e "/sys/class/net/$port" ]
then
  local dev="${port%.*}"
  # port is a vlan
  if [ "$port" != "$dev" ]
  then
    ip link delete "$port"
  fi
fi
}