#!/bin/bash

export LC_ALL=C

[ -f /etc/sysconfig/dhcpd ] && . /etc/sysconfig/dhcpd

# restart dhcpd whenever $1 interface is brought up by NM (rhbz #565921)

if [ "$2" = "up" ]; then

    # exit if the service is not configured to be started in the current runlevel

    /bin/systemctl is-enabled dhcpd.service || exit 0

    ifaces=""                # interfaces defined in DHCPDARGS

    net=$(ls /sys/class/net) # all interfaces on system

    if [ -n "${DHCPDARGS}" ]; then

        for iface in ${net}; do

            for arg in ${DHCPDARGS}; do

                [ $arg == $iface ] && ifaces="$ifaces $iface"

            done

        done

    fi

    # exit if dhcpd is not defined to listen on $1

    # i.e. if there are interfaces defined in DHCPDARGS and $1 is not among them

    if [ -n "${ifaces}" ] &&

       [[ "${ifaces}" != *$1* ]]; then

          exit 0

    fi

    # restart service

    /bin/systemctl restart dhcpd.service || :

fi