#!/bin/bash

# This script provides MSMilter daemon initialization across
# multiple Unices. 
#
# Author: Shawn Iverson <shawniverson@efa-project.org>
# 20 Aug 2018

# The below block contains various items for different Unices
# Some are required based on OS, so do not change them.

# $FreeBSD$
#
# PROVIDE: MSMilter

# Debian
#
### BEGIN INIT INFO
# Provides: MSMilter
# Required-Start: $remote_fs $network $syslog
# Required-Stop: $remote_fs $network $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: MSMilter daemon
# Description:       starts MSMilter using internal daemon mechanism
### END INIT INFO

# RHEL
#
# chkconfig: 345 80 20
# description: MSMilter daemon
# processname: MSMilter

PATH=$PATH:/usr/sbin:/usr/bin:/bin:/sbin
export PATH
NAME=MSMilter
DAEMON=/usr/sbin/MSMilter
QUICKPEEK=/usr/sbin/ms-peek
ms_conf=/etc/MailScanner/MailScanner.conf

# enable logging of non-critical notices to the maillog: yes/no
VERBOSE=yes

# basic config file
if [ -f /etc/MailScanner/defaults ] ; then
    . /etc/MailScanner/defaults
else
    echo "Aborted: missing configuration file /etc/MailScanner/defaults"
    exit 1
fi

# Exit if the MSMilter executable is not installed
[ -x $DAEMON ] || exit 0

[ -d /var/run ] || mkdir -p /var/run

# Don't start if MailScanner is not configured
if [ $run_mailscanner = 0 ]; then
    cat <<-EOF
    Edit the file /etc/MailScanner/MailScanner.conf according to
    your needs. When complete, edit /etc/MailScanner/defaults and set 
    the variable to enable MailScanner to run:

    run_mailscanner=1
EOF
    exit 0
fi

PIDFILE="`${QUICKPEEK} MilterPIDFile ${ms_conf}`"

if [ -z $PIDFILE ]; then
    PIDFILE="/var/run/MSMilter.pid"
fi

#
# Function that starts the daemon/service
#
do_start()
{
    # Return
    #   0 if daemon has been started
    #   2 if daemon could not be started
    #   3 unknown error

    # check if the daemon is already running
    # should have already been checked in the CASE
    # statement below

    # starts the daemon
    $DAEMON $ms_conf

    RETVAL="$?"

    if [ $RETVAL -eq 0 ]; then
        return 0
    else
        # unable to start the daemon
        return 2 
    fi

    # we should never get this far
    return 3
}

#
# Function that stops the daemon/service
#
do_stop()
{
    # Return
    #   0 if daemon has been stopped
    #   1 if daemon was already stopped
    #   2 if daemon could not be stopped
    #   3 unknown error

    # get the PID
    if [ -f $PIDFILE ] ; then
        PID=$(head -n 1 $PIDFILE)
    else
        # no pid
        PID=
    fi

    # no pid so MSMilter should not be running
    if [ "x$PID" = "x" ]; then
        return 1
    else
        ps wwp $PID|grep -q '[M]SMilter' > /dev/null 2>&1
        RETVAL="$?"
    fi

    if [ $RETVAL -eq 0 ]; then
        # MSMilter is running. kill it
        kill -15 $PID
        
        # Check again, up to 1.5 ish minutes
        COUNTER=0
        while [ $COUNTER -lt 40 ]; do
          ps wwp $PID|grep -q '[M]SMilter' > /dev/null 2>&1
          RETVAL="$?"
          if [[ $RETVAL -eq 0 ]]; then
            COUNTER=$((COUNTER+1))
            sleep 2
          else
            COUNTER=40
          fi
        done

        if [ $RETVAL -eq 0 ]; then
            # Process never stopped
            do_deadpid

            RETVAL="$?"

            if [ $RETVAL -eq 1 ]; then
                return 2
            else
                return 0
            fi
        fi

        # remove pid file
        if [ -f $PIDFILE ] ; then
            rm -f $PIDFILE
        fi

        # Stop successful
        return 0
    else
        # MSMilter not running but PID is present
        do_deadpid

        RETVAL="$?"

        if [ $RETVAL -eq 0 ]; then
            # Successfully removed dead PID
            return 1
        else
            # Unable to stop
            return 2
        fi
    fi

    # we should never get this far
    return 3
}

#
# Function to handle a dead PID/rogue MSMilter processes
#
# Returns:  1 if unable to stop rogue processes gracefully
#           0 if success
do_deadpid()
{
    [ "$VERBOSE" != no ] && logger -i -p mail.notice "Found a possible dead PID. Stopping all $NAME rogue processes ..."
    kill -15 $(ps axww | grep '[M]SMilter' | awk '{print $1}') > /dev/null 2>&1

    # Check again
    if [ $(ps axww | grep -q '[M]SMilter' ) ]; then
        # Unable to stop rogue processes
        return 1
    fi

    if [ -f $PIDFILE ] ; then
        rm -f $PIDFILE
    fi

    return 0
}

case "$1" in
  start)
    # check if a PID file exists
    if [ -f $PIDFILE ] ; then
        # get the PID
        PID=$(head -n 1 $PIDFILE)

        # check to see if running and belongs to MSMilter
        ps wwp $PID|grep -q '[M]SMilter' > /dev/null 2>&1

        # get the return
        RETVAL="$?"

        # if 0 it is already running
        if [ $RETVAL -eq 0 ]; then
            echo "$NAME is already running"
            exit 0
        else
            do_deadpid

            RETVAL="$?"

            if [ $RETVAL -eq 1 ]; then
                # Rogue process(es) detected, could not kill automatically
                echo "$NAME is defunct, use 'kill' option to remove any rogue processes."
                exit 1
            fi
        fi
    fi

    [ "$VERBOSE" != no ] && logger -i -p mail.notice "Starting $NAME "

    # make sure the correct permissions are set
    echo "$NAME starting ... "
    sleep 1    
    do_start

    STARTRETVAL="$?"

    if [ $STARTRETVAL -eq 0 ]; then
        [ "$VERBOSE" != no ] && logger -i -p mail.notice "$NAME started"
        sleep 1;
        PID=$(head -n 1 $PIDFILE)
        echo "$NAME started with process id $PID"
    else
        logger -i -p mail.notice "$NAME failed to start"
        do_deadpid
        exit 1
    fi
    
    ;;
  stop)
    [ "$VERBOSE" != no ] && logger -i -p mail.notice "Stopping $NAME "

    do_stop

    RETVAL="$?"

    # error in do_stop - this should never trigger
    if [ $RETVAL -eq 3 ]; then
        
        echo "There was a fatal error in stopping the daemon. Use the"
        echo "'kill' option to force any running processes to stop."
        exit 1
    fi

    # MSMilter could not be stopped
    if [ $RETVAL -eq 2 ]; then
        logger -i -p mail.notice "WARN: $NAME $DESC could not be stopped"
        echo "ERROR: Unable to stop $NAME"
        echo "ERROR: Use the 'kill' option to force stop"
        exit 1
    fi

    # MSMilter was not running
    if [ $RETVAL -eq 1 ]; then
        echo "$NAME is already stopped"
        exit 0
    fi

    # successfully stopped
    if [ $RETVAL -eq 0 ]; then

        [ "$VERBOSE" != no ] && logger -i -p mail.notice "$NAME stopped"
        echo "$NAME stopped"
        
    fi

    ;;
  status)

    if [ -f $PIDFILE ] ; then
        # get the PID
        PID=$(head -n 1 $PIDFILE)
        
       # check to see if running and belongs to MSMilter
        ps wwp $PID|grep -q '[M]SMilter' > /dev/null 2>&1

        # get the return
        RETVAL="$?"

        # if 0 it is already running
        if [ $RETVAL -eq 0 ]; then
            echo "$NAME is running under process id $PID"
            exit 0
        else
            do_deadpid

            RETVAL="$?"

            if [ $RETVAL -eq 0 ]; then
                echo "$NAME had a dead PID. Any rogue processes were killed."
            else
                # Rogue process(es) detected, could not kill automatically
                echo "$NAME is defunct, use 'kill' option to remove any rogue processes."
                exit 1
            fi
        fi
    fi

    echo "$NAME is not running"
    exit 0

    ;;
  restart)
    echo "Restarting $NAME ..."
    [ "$VERBOSE" != no ] && logger -i -p mail.notice "Restarting $NAME "

    do_stop

    RETVAL="$?"

    # error in do_stop - this should never trigger
    if [ $RETVAL -eq 3 ]; then
        echo "There was a fatal error in restarting the daemon. Use the"
        echo "'kill' option to force any running processes to stop and then start."
        exit 1
    fi

    # MSMilter could not be stopped
    if [ $RETVAL -eq 2 ]; then
        echo "ERROR: Unable to restart $NAME"
        echo "ERROR: Use the 'kill' option to force stop and then start."
        exit 1
    fi

    do_start
    STARTRETVAL="$?"

    if [ $STARTRETVAL -eq 0 ]; then
        if [ -f $PIDFILE ] ; then
            [ "$VERBOSE" != no ] && logger -i -p mail.notice "$NAME restarted"
            PID=$(head -n 1 $PIDFILE)
            echo "$NAME restarted with process id $PID"
            exit 0
        else
            logger -i -p mail.notice "$NAME failed to start"
            echo "$NAME failed to start ... doh!"
            exit 1
        fi
    else
        logger -i -p mail.notice "$NAME failed to start"
        echo "$NAME failed to start ... doh!"
        do_deadpid
        exit 1
    fi

    ;;

  reload)
    echo "Reloading $NAME ..."
    [ "$VERBOSE" != no ] && logger -i -p mail.notice "Reloading $NAME "
    do_stop

    RETVAL="$?"

    # error in do_stop - this should never trigger
    if [ $RETVAL -eq 3 ]; then
        echo "There was a fatal error in restarting the daemon. Use the"
        echo "'kill' option to force any running processes to stop and then start."
        exit 1
    fi

    # MSMilter could not be stopped
    if [ $RETVAL -eq 2 ]; then
        echo "ERROR: Unable to restart $NAME"
        echo "ERROR: Use the 'kill' option to force stop and then start."
        exit 1
    fi

    do_start

    STARTRETVAL="$?"

    if [ $STARTRETVAL -eq 0 ]; then
        if [ -f $PIDFILE ] ; then
            [ "$VERBOSE" != no ] && logger -i -p mail.notice "$NAME restarted"
            PID=$(head -n 1 $PIDFILE)
            echo "$NAME restarted with process id $PID"
            exit 0
        else
            logger -i -p mail.notice "$NAME failed to start"
            echo "$NAME failed to start ... doh!"
            exit 1
        fi
    else
        logger -i -p mail.notice "$NAME failed to start"
        do_deadpid
        exit 1
    fi

    ;;
    
  kill)
    [ "$VERBOSE" != no ] && logger -i -p mail.notice "Killing $NAME "
    echo "Killing $NAME and children ... mwa ha ha ha!"
    kill -9 $(ps axww | grep '[M]SMilter' | awk '{print $1}') > /dev/null 2>&1

    # remove pid file
    if [ -f $PIDFILE ] ; then
        rm -f $PIDFILE
    fi

    # create stopped file
    touch $stopped_lockfile

    ;;
  *)
    echo "        Usage: { start | stop | reload  | restart | kill | status }" >&2
    exit 3
    ;;
esac
exit 0