acarsdec-service

#!/bin/bash
### BEGIN INIT INFO
# Provides:          acarsdec
# Required-Start:    $all
# Required-Stop:
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Acarsdec ACARS decoder
# Description:       Acarsdec is a multi-channels acars decoder with built-in rtl_sdr front end - https://github.com/TLeconte/acarsdec

### END INIT INFO

# chkconfig: 2345 98 2
# description: shellbox service for spawning programs

export PATH=$PATH:/usr/local/bin

export HOSTNAME=$(hostname -s)

exe=/usr/bin/procServ
options="-k ^X --killsig 15 -x ^C -i ^D -c"
prog=acarsdec
params=
conf=/etc/acarsdec-service.conf
logdir=/var/log/$prog
shells=/var/run/$prog
chroot=/mnt/ramdisk

if [ -d $chroot ]
then
  CHROOT="chroot $chroot"
fi

fail () {
  echo $@
  exit 1
}

echo_failure () {
  echo " [failed]"
}

checkpid () {
  [ -d /proc/$PID ] 
}

launch () {
  if [ "$1" = "-reload" ]
  then
    reload=YES
    shift
  fi
  temp=$(mktemp -p $(dirname $shells)) || fail "can't create temporary file"
  while read PORT USER DIR COMMAND
  do
    # check for empty lines and comments
    [[ $PORT == "" || $PORT == \#* ]] && continue
    # check if already started shell is still alive
    if LINE=$(grep "$PORT $USER $DIR $COMMAND" $shells 2> /dev/null)
    then
      PID=${LINE%% *}
      if checkpid $PID
      then
        if [ -z "$reload" ] && [ -z "$*" ] || echo "$*" | grep -qE "(^|[[:space:]])$PORT([[:space:]]|$)"
        then
          echo "Already running: $PORT $USER $DIR $COMMAND"
        fi
        echo "$LINE" >> $temp
        continue
      fi
    fi

    # check if we have to start all shells or only this PORT
    [ "$*" ] && echo "$*" | grep -qvE "(^|[[:space:]])$PORT([[:space:]]|$)" && continue

    if [ -n "$logdir" ]
    then
      [ -d $logdir ] || mkdir -m 777 $logdir
      LOG=$logdir/$PORT
      rm -f $LOG
    else
      LOG=/dev/null
    fi

    # Wait for time to be sync before launching
    while true; do /usr/sbin/ntp-wait -v;  if [ $? -eq 0 ]; then break; fi; sleep 2; done

    # start shellbox as other user
    echo -n Starting: $PORT $USER $DIR $COMMAND
    export SHELLBOX=$HOSTNAME:$PORT
    #pidfile=/var/run/procServ-$PORT.pid
    pidfile=/tmp/procServ-$PORT.pid
    rm -f $pidfile
#    $exe -p $pidfile $options $DIR $params $PORT $COMMAND >> $LOG 2>&1 < /dev/null
    $CHROOT su $USER -c "$exe -p $pidfile $options $DIR $params $PORT $COMMAND >> $LOG 2>&1 < /dev/null"
    # check if starting worked or failed
    sleep 1
    if [ -e $pidfile ]
    then
      PID=$(<$pidfile)
      echo "$PID $PORT $USER $DIR $COMMAND" >> $temp
      echo
    else
      echo_failure
      echo
      cat $LOG
    fi
  done < $conf
  mv $temp $shells
  chmod 0644 $shells
}

start () {
  [ -r $conf ] || fail "$conf not readable"
  [ -x $exe ] || fail "$exe is not executable"
  launch $*
  touch /var/lock/$prog
}

stopshell() {
  PID=$1
  PORT=$2
  shift
  echo -n Stopping: $*
  kill $PID 2> /dev/null || echo_failure
  echo
  if [ $logdir ]
  then
      echo -e "\n**** stopped ****" >> $logdir/$PORT
  fi
}

stop () {
  # anything to stop?
  if [ ! -r $shells ]
  then
    echo "$prog: No shells started."
    exit 0
  fi
  if [ -z "$1" ]
  then
    # kill all shellboxes
    while read PID PORT ARGS
    do
      stopshell $PID $PORT $ARGS
    done < $shells
    rm -f $shells
    rm -f /var/lock/$prog
  else
    # kill only selected shellboxes
    temp=$(mktemp -p $(dirname $shells)) || fail "can't create temporary file"
    while read PID PORT ARGS
    do
      echo "$*" | grep -qE "(^|[[:space:]])$PORT([[:space:]]|$)" && stopshell $PID $PORT $ARGS || echo "$PID $PORT $ARGS" >> $temp
    done < $shells
    mv $temp $shells
    chmod 0644 $shells
  fi
}

reload () {
  echo "Reloading $conf: "
  [ -r $conf ] || fail "not readable"
  # anything to stop?
  if [ -r $shells ]
  then
    #first kill all shells that are not configured any more
    temp=$(mktemp -p $(dirname $shells)) || fail "can't create temporary file"
    while read PID ARGS
    do
      while read PORT USER DIR COMMAND
      do
        if [ "$PORT $USER $DIR $COMMAND" = "$ARGS" ]
        then
          echo "Keeping: $ARGS"
          echo "$PID $ARGS" >> $temp
          continue 2
        fi
      done < $conf
      stopshell $PID $PORT $ARGS
    done < $shells
    mv $temp $shells
    chmod 0644 $shells
  fi
  #now start all new shells
  sleep 1
  launch -reload
}

status () {
  [ -r $conf ] || fail "$conf not readable"
  if [ "$1" = "-log" ]
  then
    log=YES
    shift
  fi
  echo -e "pid\tport\tuser\tdir\t\t\tcommand"
  while read PORT USER DIR CMD
  do
    # check for empty lines and comments
    [[ $PORT == "" || $PORT == \#* ]] && continue

    # check if we have to report all shells
    [ "$*" ] &&  echo "$*" | grep -qvE "(^|[[:space:]])$PORT([[:space:]]|$)" && continue
    
    if [ "$logdir" -a "$log" ]
    then
      echo "-------------------------------------------------------------------"
    fi
    
    if LINE=$(grep "$PORT $USER $DIR $CMD" $shells 2> /dev/null)
    then 
      PID=${LINE%% *}
      if checkpid $PID
      then
        echo -n $PID
      else
        $SETCOLOR_FAILURE
        echo -n DEAD
        $SETCOLOR_NORMAL
      fi
    else
      $SETCOLOR_FAILURE
      echo -n STOPPED 
      $SETCOLOR_NORMAL
    fi
    echo -e "\t$PORT\t$USER\t$DIR\t$CMD"
    
    if [ "$logdir" -a "$log" ]
    then
        grep '\*\*\*\*' $logdir/$PORT 2>/dev/null
    fi
  done < $conf
}

CMD=$1
shift
case "$CMD" in
  (start)         start $*;;
  (stop)          stop $*;;
  (restart)       stop $*; sleep 1; start $*;; # kill all shells, then start again
  (reread|reload) reload $*;; # reload shellbox.conf without killing too much
  (status)        status $*;;
  (*)             echo "Usage: $0 {start [ports]|stop [ports]|restart [ports]|reload|status [-log] [ports]}" ;;
esac