#!/bin/bash

# Packfox, a tool to facilitate running Firefox with its profile stored
# in RAM (tmpfs). Copyright 2008-2009 Wicher Minnaard, wicher@gavagai.eu .
# Distributed under the WTFPL, http://smormedia.gavagai.nl/dist/packfox/COPYING
# Latest version available at http://smormedia.gavagai.nl/dist/packfox/


# Change this to match your profile
PROFILE=$(hostname)
PFDIR="${HOME}/.mozilla/firefox"
# Tar every .. seconds (regardless of changes)
TMOUT="1800"
# But not more often than every .. seconds (regardless of changes)
TMMIN="60"
# Regex for which files not to act on when they're changed.
# Use inotifywait -m -e modify -e move -e create -e delete --exclude '(/Cache/)' -r your_profile_dir
# and watch the output while browsing to determine which regex will be right for YOU.
IEXCL="(.sqlite-journal$)|(\-log.txt$)|(cookies.sqlite$)|(sessionstore\-[0-9].js$)|(/weave/)|(/Cache/)"
# Have you read everything and have you made the necessary adjustments? Then remove the line below ;-)
echo "I should read the README and adjust the script variables before running this." && exit 2


# No user servicable parts below this line.
TGT="${PFDIR}/${PROFILE}"

# Global vars
INOTYPID=""
SLEEPPID=""
PACKLOCK=""

# Cleanup function
terminate(){
  # If we are the daemon and we get SIGINTed/SIGTERMed, kill our children
  # and if not already packing, do one last round of packing.
  if [ "$(basename ${0})" == "packfox-daemon" ]
  then
    if [ -n "${INOTIFYPID}" ]; then kill ${INOTIFYPID}; fi
    if [ -n "${SLEEPPID}" ]; then kill ${SLEEPPID}; fi
    if [ -z "${PACKLOCK}" ];then packup; fi
    exit
  fi
}

# For cleaning up 
trap terminate SIGINT SIGTERM

# Suicide with goodbye note. If gxmessage is installed, use that.
seppuku(){
  echo "${1}"
  which gxmessage > /dev/null 2>&1 && gxmessage -nofocus -title "$(basename ${0})" "${1}" || xmessage "${1}"
  exit 2
}

# Checks and setup
test -d "${PFDIR}" || seppuku "Profile dir doesn't exist"
if [ -z "$(mount -t tmpfs | grep -F "${TGT}" )" ]
then
    mount "${PFDIR}/${PROFILE}" || seppuku "Mounting of profile's tmpfs failed. Check /etc/fstab and the output of 'dmesg'."
fi
test -f "${TGT}/.unpacked" || tar -xpf "${PFDIR}/${PROFILE}.packed.tar" -C "${PFDIR}" \
&& touch "${TGT}/.unpacked" || seppuku "Error unpacking the profile tarball. You might want to use the backup tarball located in ${PFDIR}."

# This tars up the profile
packup(){
  PACKLOCK="locked"  
  cd "${PFDIR}"
  tar --exclude '.unpacked' -cpf "${PFDIR}/${PROFILE}.packed.tmp.tar" "${PROFILE}"
  mv "${PFDIR}/${PROFILE}.packed.tar" "${PFDIR}/${PROFILE}.packed.tar.old"
  mv "${PFDIR}/${PROFILE}.packed.tmp.tar" "${PFDIR}/${PROFILE}.packed.tar"
  PACKLOCK=""
}

# No daemon, just packing
if [ "$(basename ${0})" == "packfox" ]; then packup; fi

# The daemon loop
if [ "$(basename ${0})" == "packfox-daemon" ]
then
  which inotifywait >/dev/null 2>&1 || seppuku " You'll need the 'inotify-tools' package for this script. Get it at http://inotify-tools.sourceforge.net or from your distro's repos".
  while true
    do inotifywait -q -q -t ${TMOUT} -e modify -e move -e create -e delete --exclude "${IEXCL}" \
    -r "${PFDIR}/${PROFILE}" &
    INOTYPID=${!}
    wait ${INOTYPID}; INOTIFYPID=""

    packup

    sleep ${TMMIN} &
    SLEEPPID=${!}
    wait ${SLEEPPID}; SLEEPPID=""
    done
  exit
fi