bootstrap-umount

   1 #!/bin/sh
   2 # Copyright (C) 2009 Alejandro Mery <amery@geeks.cl>
   3 #
   4 # More information can be found in the files COPYING and README.
   5 #
   6 # This script is free software; you can redistribute it and/or modify
   7 # it under the terms of the GNU General Public License as published by
   8 # the Free Software Foundation; version 3 of the License, or at your
   9 # choice any newer version. A copy of the GNU General Public License
  10 # can be found in the file COPYING.
  11 #
  12
  13 # Unmounts a partition from an image file
  14
  15 usage() {
  16         [ $# -eq 0 ] || error "$*"
  17         cat >&2 <<-EOT
  18
  19         Usage: $0 <filename|dir>
  20         EOT
  21         exit 1
  22 }
  23
  24 . "${0%/*}/bootstrap.in"
  25
  26 while [ $# -gt 0 ]; do
  27         case "$1" in
  28         --)     shift; break
  29                 ;;
  30         -*)     usage "$1: Invalid option."
  31                 ;;
  32         *)      break
  33                 ;;
  34         esac
  35         shift
  36 done
  37
  38 [ $# -eq 1 ] || usage
  39
  40 set -e
  41 if [ -b "$1" ]; then
  42         # device
  43         loop="$1"
  44         mount=$(grep "^$loop " /proc/mounts | cut -d' ' -f2)
  45 elif [ -d "$1" ]; then
  46         # directory
  47         mount=$(cd "$1"; pwd -P)
  48         loop=$(grep "^[^ ]\+ $mount " /proc/mounts | cut -d' ' -f1)
  49 elif [ -s "$1" ]; then
  50         # image
  51         loop=$(losetup -j "$1" | cut -d: -f1)
  52         mount=$(grep "^$loop " /proc/mounts | cut -d' ' -f2)
  53 else
  54         usage "$1: Invalid argument."
  55 fi
  56
  57 if [ -b "$loop" ]; then
  58         if [ -d "$mount" ]; then
  59                 echo "mount: unmouting $mount"
  60                 umount "$mount"
  61         fi
  62
  63         echo "losetup: releasing $loop"
  64         losetup -d "$loop"
  65 fi