TIMESYNCD_CONF=/run/systemd/timesyncd.conf.d/01-dhclient.conf

timesyncd_servers_setup_remove() {
        if [ ! -d /run/systemd/system ]; then
                return
        fi
        if [ ! -x /usr/lib/systemd/systemd-timesyncd ]; then
                return
        fi

        if [ -e $TIMESYNCD_CONF ]; then
                rm -f $TIMESYNCD_CONF
                systemctl try-restart systemd-timesyncd.service || true
        fi
}

timesyncd_servers_setup_add() {
        if [ ! -d /run/systemd/system ]; then
                return
        fi
        if [ ! -x /usr/lib/systemd/systemd-timesyncd ]; then
                return
        fi

        if [ -e $TIMESYNCD_CONF ] && [ "$new_ntp_servers" = "$old_ntp_servers" ]; then
                return
        fi

        if [ -z "$new_ntp_servers" ]; then
                timesyncd_servers_setup_remove
                return
        fi

        mkdir -p $(dirname $TIMESYNCD_CONF)
        cat <<EOF > ${TIMESYNCD_CONF}.new
# NTP server entries received from DHCP server
[Time]
NTP=$new_ntp_servers
EOF
        mv ${TIMESYNCD_CONF}.new ${TIMESYNCD_CONF}
        systemctl try-restart systemd-timesyncd.service || true
}


case $reason in
        BOUND|RENEW|REBIND|REBOOT)
                timesyncd_servers_setup_add
                ;;
        EXPIRE|FAIL|RELEASE|STOP)
                timesyncd_servers_setup_remove
                ;;
esac