#!/bin/sh
#
# Copyright (c) 2010 Adam Cécile (Le_Vert) <gandalf@le-vert.net>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

# How to use it:
#
# Copy this file to /usr/bin
# Create aliases for all commands that may make you suffer from fsck.
#
# In example, on Debian, add the following lines to /etc/bash.bashrc
# and /etc/profile:
# # Reboot/Halt/Shutdown aliases
# alias shutdown='/usr/bin/fsck-or-not.sh shutdown'
# alias halt='/usr/bin/fsck-or-not.sh halt'
# alias reboot='/usr/bin/fsck-or-not.sh reboot'
#
# If you want to make it works with sudo too, edit /etc/bash.bashrc
# and /etc/profile again to add:
# alias sudo='sudo '
#
# Here is an extract from bash manpage that explains the needs of
# this sudo alias:
# If the last character of the alias value is a blank, then the next
# command word following the alias is also checked for alias expansion.
#
# Each time you tape either shutdown, halt or reboot, this script
# will check if any currently mounted EXT filesystem requires fsck
# and thus, will ask you for confirmation before running the real
# command.

# Initialize a global variable set to 1 if at least fs needs fsck
globalneedfsck=0

# Check currently mounted ext2/3/4 filesystems
for fs in `mount | grep -E ' ext[234] ' | cut -d' ' -f1`; do
  # Initialize a variable to store fs state
  needfsck=0

 # Get filesystem state
  state=`tune2fs -l ${fs} | grep -E '^Filesystem state:[[:space:]]+' | cut -d':' -f2 | sed 's/[[:space:]]*//'`
  # Get current mount count
  mountcount=`tune2fs -l ${fs} | grep -E '^Mount count:[[:space:]]+' | cut -d':' -f2 | sed 's/[[:space:]]*//'`
  # Get maximum mount count
  maximummountcount=`tune2fs -l ${fs} | grep -E '^Maximum mount count:[[:space:]]+' | cut -d':' -f2 | sed 's/[[:space:]]*//'`
  # Get next check date
  nextcheck=`tune2fs -l ${fs} | grep -E '^Next check after:[[:space:]]+' | awk -F': ' '{ print $2 }' | sed 's/^[[:space:]]*//' | sed 's/[[:space:]]*$//'`
  # Get last mount date (to check "last mount in future)
  lastmount=`tune2fs -l ${fs} | grep -E '^Last mount time:[[:space:]]+' | awk -F': ' '{ print $2 }' | sed 's/^[[:space:]]*//' | sed 's/[[:space:]]*$//'`
  # Convert next check date to timestamp
  nextchecktimestamp=`LANG=C date "+%s" -d "${nextcheck}"`
  # Convert last mount time into timestamp
  lastmounttimestamp=`LANG=C date "+%s" -d "${lastmount}"`
  # Get current date as timestamp and add 10 minutes (time to stop+time to boot)
  nowtimestamp=`LANG=C date -d "+10 minutes" "+%s"`
  # Get current mount point
  mountpoint=`mount | grep -E "^${fs}" | sed 's/^.* on \(.*\) type .*$/\1/'`

 # Here we go...
  # State is not clean => fsck
  if [ "${state}" != "clean" ]; then
    needfsck=1
  fi
  # Current mount count >= maximum mount count => fsck
  if [ ${mountcount} -ge ${maximummountcount} ]; then
    needfsck=1
  fi
  # Current date +10minutes >= next check date => fsck
  if [ ${nowtimestamp} -ge ${nextchecktimestamp} ]; then
    needfsck=1
  fi
  # Last mount time in future => fsck
  if [ ${lastmounttimestamp} -gt ${nowtimestamp} ]; then
    needfsck=1
  fi
 
  # Print a warning and set global variable to 1
  if [ ${needfsck} -eq 1 ]; then
    echo "Device ${fs} mounted on ${mountpoint} will be checked at next boot."
    globalneedfsck=1
  fi
done

# Global warning and confirmation question
if [ ${globalneedfsck} -eq 1 ]; then
  echo
  echo "At least one filesystem will be check at next boot."
  echo "Are you sure you want to continue? (N/y)"
  read answer
  case ${answer} in
    y* | Y* )
      # Exec parameters
      exec "$@"
    ;;
  esac
# No fsck needed, run the command passed as argument
else
  exec "$@"
fi

# Check currently mounted ext2/3/4 filesystems
for fs in `mount | grep -E ' ext[345] ' | cut -d' ' -f1`; do

# Check currently mounted ext2/3/4 filesystems
for fs in `mount | grep -E ' ext[234] ' | cut -d' ' -f1`; do