#!/bin/sh
# This script must be executed with parameter "--start" at the end of distro shutdown
# What it does is it executes as init (process 1) and unmounts all filesystems
# including union and the USB device (if any), so it can be cleanly removed
#
# Simply add the following as the last command executed by init on your distro
# instead of the actual poweroff or shutdown command:
#
#       /mnt/live/lib/cleanup --start poweroff
#    or
#       /mnt/live/lib/cleanup --start shutdown
#
#    on Slackware, add this to rc.0:
#       /mnt/live/lib/cleanup --start /sbin/$command
#
# It may be needed to call this script with --kill from your shutdown scripts
# instead of calling regular killall5, to prevent fuse filesystems from being killed
#
# Author: Tomas M <http://www.linux-live.org/>
#

if [ "$1" = "--killall5" ]; then
   # kill all unneeded processes, which have smaller ID then the ID of
   # current shell's parent process. We can't use killall5, as it would kill some
   # processes which may be currently needed, for example fuse filesystems (ntfs-3g).
   for pid in $(/mnt/live/bin/ps | grep -v "PID" | grep -E -v "\[.*\]" | grep -E -v "mount|posixovl|fuse" | sed -r "s/^ +//" | cut -d " " -f 1); do
      if [ $pid -lt $PPID ]; then
         LIST="$LIST $pid"
      fi
   done

   kill -SIGTERM $LIST 2>/dev/null # SIGTERM
   sleep 2 # give processes some time to end
   kill -SIGKILL $LIST 2>/dev/null # SIGKILL
fi

if [ "$1" = "--start" ]; then
   # this is our first call. We will setup everything so the actual init actually
   # reloads, but calls this script again instead of itself
   cd /mnt/live
   cp "$0" sbin/init
   pivot_root . memory/union
   echo "$2" > /lib/command
   chroot /memory/union /sbin/telinit u
fi

if [ "$1" = "--init" ]; then
   # now we're called from init to replace the process nr 1.
   # All other processes are already killed
   # so our goal is just to unmount everything

   # First, mount proc again since it will be beeded
   mount -t proc proc /proc >/dev/console 2>&1

   # next, unmount everything
   umount /memory/union/sys/fs/cgroup >/dev/console 2>&1
   umount /memory/union/dev/pts >/dev/console 2>&1
   umount /memory/union/dev >/dev/console 2>&1
   umount /memory/union/run >/dev/console 2>&1
   umount /memory/union/sys >/dev/console 2>&1
   umount /memory/union/proc >/dev/console 2>&1
   umount /memory/union >/dev/console 2>&1
   umount /memory/bundles/* >/dev/console 2>&1
   umount /memory/data* >/dev/console 2>&1
   mount -n -o remount,ro /memory/data >/dev/console 2>&1

   # if debug is requested, start commandline prompt here
   if grep -vq debug /proc/cmdline; then
      echo Starting shell for debug >/dev/console
      /bin/sh < /dev/console >/dev/console 2>&1
   fi

   cat /proc/mounts >/dev/console 2>&1
   $(cat /lib/command 2>/dev/null)
   reboot
fi