#!/bin/sh

DAEMON=virtualip
. /etc/init.d/modlibrc

ipv4bcast () {
	local IP1=${1%%.*.*.*}
	local IP2=${1#*.};	IP2=${IP2%%.*.*}
	local IP3=${1#*.*.};	IP3=${IP3%%.*}
	local IP4=${1#*.*.*.}
	local NM1=${2%%.*.*.*}
	local NM2=${2#*.};	NM2=${NM2%%.*.*}
	local NM3=${2#*.*.};	NM3=${NM3%%.*}
	local NM4=${2#*.*.*.}
	local IIP=$(($IP1 << 24 | $IP2 << 16 | $IP3 << 8 | $IP4))
	local INM=$(($NM1 << 24 | $NM2 << 16 | $NM3 << 8 | $NM4))
	local IBC=$((${IIP} | ~${INM}))
	printf "%u.%u.%u.%u" $((${IBC} >> 24 & 0xFF)) $((${IBC} >> 16 & 0xFF)) \
		$((${IBC} >> 8 & 0xFF)) $((${IBC} & 0xFF))
}

start() {
	echo -n 'Setting up virtual network interface ... '

	if [ -n "$(ifconfig | grep "$VIRTUALIP_INTERFACE")" ]; then
		echo 'already running.'
		exit 1
	fi

	VIRTUALIP_BROADCAST=$(ipv4bcast $VIRTUALIP_IP $VIRTUALIP_NETMASK)

	ifconfig $VIRTUALIP_INTERFACE $VIRTUALIP_IP netmask $VIRTUALIP_NETMASK broadcast $VIRTUALIP_BROADCAST up > /dev/null 2>&1
	exitval=$?
	if [ "$exitval" -eq 0 ]; then
		echo 'done.'
	else
		echo 'failed.'
		exit $exitval
	fi
}

stop() {
	echo -n 'Deactivating virtual network interface ... '

	if [ -z "$(ifconfig | grep "$VIRTUALIP_INTERFACE")" ]; then
		echo 'not running.'
		exit 1
	fi

	ifconfig $VIRTUALIP_INTERFACE down > /dev/null 2>&1 > /dev/null 2>&1
	exitval=$?
	if [ "$exitval" -eq 0 ]; then
		echo 'done.'
	else
		echo 'failed.'
		exit $exitval
	fi
}

case $1 in
	""|load)
		modreg cgi 'virtualip' 'Virtual IP'
		modreg daemon $DAEMON

		if [ "$VIRTUALIP_ENABLED" != "yes" ]; then
			echo "$DAEMON is disabled" 1>&2
			exit 1
		fi

		start
		;;
	start)
		start
		;;

	stop)
		stop
		;;
	unload)
		modunreg daemon $DAEMON
		modunreg cgi 'virtualip'
		stop
		;;
	restart)
		stop
		start
		;;
	status)
		if [ -z "$(ifconfig | grep "$VIRTUALIP_INTERFACE")" ]; then
			echo 'stopped'
		else
			echo 'running'
		fi
		;;
	*)
		echo "Usage: $0 [load|unload|start|stop|restart|status]" 1>&2
		exit 1
		;;
esac

exit 0