#!/bin/sh

export LC_ALL=C

if ! /usr/bin/systemctl is-enabled ddupdate.timer >/dev/null 2>&1; then
    exit 0
fi

case "$2" in
    "down")
        if /sbin/ip route ls | grep -q '^default'; then
	    exit 0
	fi
	/usr/bin/logger "ddupdate: default interface down: stopping timer" || :
        /usr/bin/systemctl stop ddupdate.timer || :
	;;
    "up")
        if /sbin/ip -o route show dev "$1" | grep -q '^default'
	then
	    /usr/bin/logger \
		"ddupdate: default interface up: starting timer" || :
            /usr/bin/systemctl start ddupdate.timer || :
	fi
	;;
    *)
        ;;
esac
