#!/bin/bash

# $Id$

if [ $# = 0 ]
then
  echo "Script to restart SqueezeCenter over and over again."
  echo "This has to be done since the mysql-server is sometimes"
  echo "restarted due to upgrades and log-rotation and this causes"
  echo "SqueezeCenter to exit."
  echo
  echo "To stop SqueezeCenter, kill this script instead of the"
  echo "actual SqueezeCenter process."
  echo
  echo "Usage: $0 <squeezecenter-binary> <squeezecenter-arguments>"
  exit 1
fi

function clean_up {
  # Kill the SqueezeCenter daemon if it is running
  kill $SLIMPID
  echo `date "+%F %H:%M:%S"` "squeezecenter_safe stopped." >> /var/log/squeezecenter/server.log
  exit
}

trap clean_up SIGINT SIGHUP SIGTERM

echo `date "+%F %H:%M:%S"` "squeezecenter_safe started." >> /var/log/squeezecenter/server.log

while true
do
  # From the Bash Reference Manual:
  # When Bash receives a signal for which a trap has been set 
  # while waiting for a command to complete, the trap will not 
  # be executed until the command completes. When Bash is waiting
  # for an asynchronous command via the wait builtin, the reception
  # of a signal for which a trap has been set will cause the wait
  # builtin to return immediately with an exit status greater than
  # 128, immediately after which the trap is executed.

  "$@" > /dev/null 2>&1 &
  SLIMPID=$!
  
  # wait for SqueezeCenter to get started before wait()
  sleep 15
  
  wait $SLIMPID
  echo `date "+%F %H:%M:%S"` "SqueezeCenter died. Restarting." >> /var/log/squeezecenter/server.log

  # Normally, when SqueezeCenter realizes that the mysql-connection is gone,
  # the mysql server has already been started again. So no need to sleep
  # here.

done