#! /bin/sh
#
### BEGIN INIT INFO
# Provides:       radvd
# Required-Start: $remote_fs $named $syslog
# Required-Stop:  $remote_fs $named $syslog
# Default-Start:  3 5
# Default-Stop:   0 1 2 6
# Description:    router advertisement daemon
### END INIT INFO

PATH=/sbin:/bin:/usr/sbin:/usr/bin
DAEMON=/usr/sbin/radvd
NAME=radvd
DESC=radvd
CONFIG=/etc/radvd.conf
SAVED_SETTINGS=/var/run/radvd/saved-settings
PIDFILE=/var/run/radvd/radvd.pid
OPTIONS="-u radvd -p $PIDFILE"

test -x $DAEMON || exit 0

set -e

# Check for IPv6 support in kernel
if test \! -e /proc/sys/net/ipv6; then
  echo "IPv6 support must be enabled in the kernel for $DESC to work."
  exit
fi

save_settings()
{
    local file=$1
    
    rm -f $file
    for if_conf in /proc/sys/net/ipv6/conf/*; do
	echo -e "$if_conf/forwarding\t `cat $if_conf/forwarding`" >> $file
    done
    return 0
}

restore_settings()
{
    file=$1
    
    if [ ! -f $file ]; then
	echo "$0: warning: cannot restore settings"
	return
    fi
    
    ( 
	while read f value; do
	    if [ -w $f ]; then
		echo $value > $f
	    fi
	done
    ) < $file
}

chkconfig() {
    if [ ! -e $CONFIG -o ! -s $CONFIG ]; then
        echo ""
	echo "* $CONFIG does not exist or is empty." 
	echo "* See /usr/share/doc/radvd/examples/simple-radvd.conf for a simple"
	echo "* configuration suitable for most systems, and radvd.conf(5)"
	echo "* for configuration file syntax. radvd will *not* be started."
	exit 0
    fi
}

case "$1" in
  start)
	echo -n "Starting $DESC: "
	chkconfig
	save_settings $SAVED_SETTINGS
	
        # We must enable IPv6 forwarding for radvd to work
	echo 1 > /proc/sys/net/ipv6/conf/all/forwarding

	# Check for stale pidfile; radvd won't start if one is lying around
	if [ -f $PIDFILE ] && ! ps `cat  $PIDFILE` > /dev/null; then
	  rm -f $PIDFILE
	fi
	if ! start-stop-daemon --oknodo --start --pidfile $PIDFILE \
		--exec $DAEMON -- $OPTIONS; then
	  echo "failed." && exit 1
	fi
	echo "$NAME."
	;;
  stop)
	echo -n "Stopping $DESC: "
	start-stop-daemon --oknodo --stop --pidfile $PIDFILE \
		--exec $DAEMON
	restore_settings $SAVED_SETTINGS
	rm -f $SAVED_SETTINGS
	echo "$NAME."
	;;
  reload|force-reload)
	echo "Reloading $DESC configuration files."
	start-stop-daemon --stop --signal HUP --quiet --pidfile \
	    $PIDFILE --exec $DAEMON
	;;
  restart)
	chkconfig
	echo -n "Restarting $DESC: "
	if ! start-stop-daemon --stop --quiet --pidfile \
		$PIDFILE --exec $DAEMON; then
	  # stop failed, so we were not running
	  save_settings $SAVED_SETTINGS
	  echo 1 > /proc/sys/net/ipv6/conf/all/forwarding
	fi
	sleep 1
	start-stop-daemon --start --quiet --pidfile \
		$PIDFILE --exec $DAEMON -- $OPTIONS
	echo "$NAME."
	;;
  *)
	N=/etc/init.d/$NAME
	echo "Usage: $N {start|stop|restart|reload|force-reload}" >&2
	exit 1
	;;
esac

exit 0
