uck-remaster-unpack-rootfs

#!/bin/bash

###################################################################################
# UCK - Ubuntu Customization Kit                                                  #
# Copyright (C) 2006-2010 UCK Team                                                #
#                                                                                 #
# UCK 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 3 of the License, or               #
# (at your option) any later version.                                             #
#                                                                                 #
# UCK 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 UCK.  If not, see <http://www.gnu.org/licenses/>.                    #
###################################################################################

#############################
# general purpose functions #
#############################

function usage()
{
	echo "Usage: $0 [-m] [remaster-dir]"
}

function failure()
{
	echo "$@"
	exit 1
}

#########################
# input parameter check #
#########################
use_mount=false
if [ x"$1" = x-m ]; then
	use_mount=true; shift
fi

REMASTER_HOME="$1"

if [ -z "$REMASTER_HOME" ]; then
	REMASTER_HOME=~/tmp
fi

########
# main #
########

. libraries/remaster-live-cd.sh 2>/dev/null ||
	. /usr/lib/uck/remaster-live-cd.sh 2>/dev/null ||
	failure "libraries not found"

SQUASHFS_MOUNT_DIR="$REMASTER_HOME/remaster-root-mount"
SQUASHFS_IMAGE="$REMASTER_HOME/remaster-iso/casper/filesystem.squashfs"
REMASTER_DIR="$REMASTER_HOME/remaster-root"

# Check for previous use of union mounts and implicitly turn on -m iff found
if [ -d "$REMASTER_DIR"-cache ]; then
	use_mount=true
fi

if [ $use_mount = true ] && check_union_mounts; then
	# Mount r/W copy of rootfs on iso
	if mountpoint "$REMASTER_DIR"; then
		: do nothing - is already mounted
	else
		union_mount "$SQUASHFS_IMAGE" "$REMASTER_DIR" ||
			failure "Can't union_mount $REMASTER_DIR"
	fi
	# Prevent immediate unmount by cleanup code
	trap : EXIT
else
	if [ $use_mount = true ]; then
		echo "Cannot use union mounts - using copy instead!"
		use_mount=false
	fi
	remove_remaster_dir
	mount_squashfs
	unpack_rootfs
	unmount_squashfs
fi