#!/usr/bin/sh
#------------------------------------------------------------------------------
# /usr/sbin/setdate - set date to current time
#
# Copyright (c) 2001-2024  The Eisfair Team, team(at)eisfair(dot)org
#
# Creation:    2003-11-14  jed
# Last Update: $Id$
#
# Usage:       setdate [--quiet]
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#------------------------------------------------------------------------------

# include eislib
. /var/install/include/eislib

#exec 2> /tmp/netdate-trace-$$.log
#set -x

#------------------------------------------------------------------------------
# check_backgroundprocess
# =======================
#  Parameters:     $1    waittime until background process, if not
#                        already terminated, will be killed
#                  $2    PID of background process
#
#  Returns:        0     background process terminated
#                  1     background process was killed
#
# Thank you Ansgar for your help solving this annoying udp timeout/connection
# problem and the hang-at-boot-time problem :-)
#------------------------------------------------------------------------------
check_backgroundprocess()
{
    # sleep 1 second
    SLEEPTIME=1

    # wait at most $1 seconds
    WAITTIME=$1
    RTIME=$1
    PID=$2

    # loop
    while [ ${RTIME} -gt 0 ]
    do
        sleep ${SLEEPTIME}

        # check process $2
        kill -0 ${PID} >/dev/null 2>/dev/null
        RC=$?

        if [ ${RC} = 1 ]
        then
            # process terminated
            return 0
        else
            RTIME=`expr ${RTIME} - ${SLEEPTIME}`
        fi
    done

    # process still lives
    kill -9 ${PID} >/dev/null 2>&1

    return 1
}

#==============================================================================
# main
#==============================================================================

. /etc/config.d/netdate

if [ "${NETDATE_DO_DEBUG}" = "yes" ]
then
    set -x
fi

# file names
netdate_tmpfile=/tmp/netdate.$$
netdate_e_tmpfile=/tmp/netdate_e.$$
netdate_s_tmpfile=/tmp/netdate_s.$$
netdate_r_tmpfile=/tmp/netdate_return.$$

# command line parameter
if [ "$1" = '-quiet' -o "$1" = '--quiet' ]
then
    qflag='-quiet'
    shift
fi

if [ "${START_NETDATE}" = 'yes' ]
then
    # get timeserver
    checked_servers=''
    server_port=37        # port 37 - time protocol
    server_protocol=''
    for SVRNAME in ${NETDATE_TIMESERVER}
    do
        if [ "${SVRNAME}" = "tcp" -o "${SVRNAME}" = "udp" ]
        then
            # save protocol
            server_protocol=${SVRNAME}
        else
            # check if timeserver(s) can be reached
            # nc command line switches:
            #  -w  - timeout in seconds
            #  -v  - be verbose
            #  -z  - scan for listening daemons, without sending any data to them
            for count in 1 2 3 4
            do
                /usr/bin/nc -w 2 -z ${SVRNAME} ${server_port} 2>/dev/null
                ret=${?}

                if [ ${ret} -eq 0 ]
                then
                    break
                fi

                sleep 2
            done

            if [ ${ret} -eq 0 ]
            then
                if [ -z "${checked_servers}" ]
                then
                    checked_servers="${server_protocol} ${SVRNAME}"
                else
                    checked_servers="${checked_servers} ${server_protocol} ${SVRNAME}"
                fi

                server_protocol=''
            else
                if [ "${qflag}" != "-quiet" ]
                then
                    echo "- skipping timeserver '${SVRNAME}', because it cannot be reached or the port is not accessible!"
                fi
            fi
        fi
    done

    # remove optional protocols from display string
    display_checked_servers=`echo "${checked_servers}" | sed 's/udp//g;s/tcp//g;s/^ *//' | tr -s ' ' ' '`

    if [ -n "${checked_servers}" ]
    then

        # display checked_servers only if not empty
        if [ "${qflag}" != "-quiet" ]
        then
            mecho
            mecho "Syncing time using timeserver(s) '${display_checked_servers}':"
        fi

        # save stderr
        exec 3>&2
        # redirect stderr to /dev/null
        # this will also disable set -x output!
        exec 2>/dev/null

        # sync time
        (
            /usr/sbin/netdate -l 10 ${checked_servers} > ${netdate_s_tmpfile} 2> ${netdate_e_tmpfile};
            echo $? > ${netdate_r_tmpfile}
        ) >/dev/null 2>&1 &
        BPID=$!

        # assume no error
        ret=0

        # check background process
        # wait at most 30 seconds
        if ! check_backgroundprocess 30 ${BPID} >/dev/null 2>&1
        then
            # only the sourrounding shell was killed
            # get PID of netdate command and kill it too
            BPID_ND=`ps -eo "%p %c %a" | grep "/usr/sbin/netdate -l 10" | sed 's/^ *//' | cut -f1 -d' '`
            BPID_ND=`echo $BPID_ND`
            [ -z "$BPID_ND" ] && kill -9 $BPID_ND >/dev/null 2>&1

            echo "Error: Aborting time synchronisation due to a timeout condition." >> ${netdate_e_tmpfile}
            ret=1
        fi

        # check and remove netdate_return file
        if [ -f ${netdate_r_tmpfile} ]
        then
            ret=`cat ${netdate_r_tmpfile}`
            rm ${netdate_r_tmpfile}
        fi

        cat ${netdate_s_tmpfile} ${netdate_e_tmpfile} > ${netdate_tmpfile}
        rm -f ${netdate_s_tmpfile} ${netdate_e_tmpfile}

        if [ ${ret} -eq 0 ]
        then
            # adjust time drift
            /usr/sbin/hwclock --adjust | grep -v 'Needed adjustment is less than one second'

            # set hw clock
            /usr/sbin/hwclock --systohc --utc
        fi

        # restore stderr, close &3
        exec 2>&3 3>&-
        #test echo "Check stderr" >&2
        #test echo "Check stdout" >&1

        # strip CR
        /usr/bin/dtou ${netdate_tmpfile}

        if [ "${qflag}" != "-quiet" ]
        then
            # show result
            cat ${netdate_tmpfile}
        fi

        if [ "$NETDATE_LOGGING" = "yes" ]
        then
            # write to syslog
            /usr/bin/logger -t "netdate" -p "local0.info" "Syncing time using timeserver ${display_checked_servers}"

            while read line
            do
                /usr/bin/logger -t "netdate" -p "local0.info" "${line}"
            done < ${netdate_tmpfile}
        fi

        # delete tmp file
        rm -f ${netdate_tmpfile}
    else
        if [ "${qflag}" != "-quiet" ]
        then
            mecho --error "No timeservers are reachable, syncing aborted!"
        fi

        if [ "${NETDATE_LOGGING}" = "yes" ]
        then
            /usr/bin/logger -t "netdate" -p "local0.error" "No timeservers are reachable, syncing aborted!"
        fi
    fi
else
    if [ "${qflag}" != "-quiet" ]
    then
        mecho --info "Time syncing has been disabled"
    fi
fi

if [ "${NETDATE_DO_DEBUG}" = "yes" ]
then
    set +x
fi
#==============================================================================
# end
#==============================================================================