#!/bin/sh
# Copyright (C) 2006 OpenWrt.org

. /etc/functions.sh

unset IFACE
unset SERVER
unset PORT
unset INTERVAL
unset COUNT
NTPC=`which ntpclient`

check_server() {
	local hostname
	local port
	[ -n "$SERVER" ] && return
	config_get hostname $1 hostname
	config_get port $1 port
	[ -z "$hostname" ] && return
	$NTPC -c 1 -p ${port:-123} -h $hostname > /dev/null && { SERVER=$hostname; PORT=${port:-123}; }
}

set_drift() {
	config_get freq $1 freq
	[ -n "$freq" ] && adjtimex -f $freq >/dev/null
}

start_ntpclient() {
	config_foreach set_drift ntpdrift
	config_foreach check_server ntpserver
	[ -z "$SERVER" ] && exit 0
	logger starting ntpclient
	$NTPC ${COUNT:+-c $COUNT} ${INTERVAL:+-i $INTERVAL} -D -p $PORT -h $SERVER 2> /dev/null
}

stop_ntpclient() {
	logger stopping ntpclient
	killall ntpclient
}

load_settings() {
	local interval
	local count
	local iface
	
	config_get interval $1 interval
	config_get count $1 count
	config_get iface $1 iface
	
	[ -n "$iface" ] && IFACE=$iface
	[ -n "$count" ] && COUNT=$count
	[ -n "$interval" ] && INTERVAL=$interval
}

config_load ntpclient
config_foreach load_settings ntpclient

# check if we only listen to a single iface
[ -n "$IFACE" -a "$IFACE" != "$INTERFACE" ] && exit 0 

DEF_ROUTE=`route -n | grep '^0.0.0.0'`                                     
NTP_RUNNING=`ps  | grep $NTPC | grep -v grep`

case "${ACTION:-ifup}" in
	ifup)
		[ -n "$DEF_ROUTE" -a -z "$NTP_RUNNING" ] && start_ntpclient 
	;;
	ifdown)
		[ -n "$NTP_RUNNING" ] && stop_ntpclient 
	;;
esac