utils/docker/entrypoint_docker-compose.sh

   1 #! /bin/bash -e
   2
   3 # docker stop trap signals
   4 # https://medium.com/@gchudnov/trapping-signals-in-docker-containers-7a57fdda7d86#.5d6q01x7q
   5
   6 pid=0
   7 command=""
   8 term_recvd=0
   9
  10 # send SIGTERM also to the executed command in the docker container (the containernet topology)
  11 # SIGTERM-handler
  12 function term_handler() {
  13   echo $command
  14   pid=$(pgrep -f "$command" | sed -n 1p)
  15
  16   pid="$!"
  17   # avoid that the process triggers its own handler by sending sigterm
  18   if [ $pid -ne 0 ] && [ $term_recvd -eq 0 ]; then
  19     echo "sigterm received"
  20     echo $pid
  21     term_recvd=1
  22     kill -SIGTERM "$pid"
  23   fi
  24
  25   wait "$pid"
  26
  27   # do some manual cleanup
  28   # remove all containers started by son-emu
  29   docker ps -a -q --filter="name=mn.*" | xargs -r docker rm -f
  30   # cleanup remaining mininet
  31   mn -c
  32
  33   sleep 5
  34   exit 143; # 128 + 15 -- SIGTERM
  35 }
  36
  37 # setup handlers
  38 # on callback, kill the last background process, which is `tail -f /dev/null` and execute the specified handler
  39 trap 'term_handler' SIGTERM
  40
  41
  42 service openvswitch-switch start
  43
  44 if [ ! -S /var/run/docker.sock ]; then
  45     echo 'Error: the Docker socket file "/var/run/docker.sock" was not found. It should be mounted as a volume.'
  46     exit 1
  47 fi
  48
  49 # this cannot be done from the Dockerfile since we have the socket not mounted during build
  50 echo 'Pulling the "ubuntu:trusty" image ... please wait'
  51 docker pull 'ubuntu:trusty'
  52
  53 echo "Welcome to Containernet running within a Docker container ..."
  54
  55 if [[ $# -eq 0 ]]; then
  56     exec /bin/bash
  57 else
  58     #remember command to send it also the SIGTERM via the handler
  59     command=$*
  60     echo $command
  61     exec $* &
  62     # wait indefinetely
  63     while true
  64     do
  65       sleep 1
  66     done
  67     echo "done"
  68 fi