#!/bin/sh
# -*- coding: utf-8 -*-
#
# «casper-new-uuid» - Creates and injects new UUIDs for casper disks
#
# Create new UUIDs for disks to prevent conflicts and booting the wrong casper
# directory.  Particularly useful in creating recovery disks that need to be
# able to also work with recovery partitioning schemes.
#
# Copyright (C) 2008, Dell Inc.
#
# Author:
#  - Mario Limonciello <Mario_Limonciello@Dell.com>
#
# This script 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 application; if not, write to the Free Software Foundation, Inc., 51
# Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
##################################################################################

set -e

help() {
 echo
 echo "USAGE: $0 initrd.{l,g}z <path-to-new-initrd> <path-to-new-casper-uuid> "
 echo
 echo "initrd.{l,g}z is the absolute path to the original gzipped or lzmaed initramfs"
 echo "<path-to-new-initrd> is the destination directory for the new compressed initramfs"
 echo "<path-to-new-casper-uuid> is the destination directory for the new casper-uuid-TYPE "
 echo
 echo "if either path is absent, they will end up in the current directory "
 echo "TYPE is determined by an already existing casper-uuid-* or by 'uname -s'"
}

if [ "$#" = "0" ] || [ "x$1" = x-h ] || [ "x$1" = x--help ]; then
	help
	exit 3
fi

CWD=`pwd`
TEMPDIR=`mktemp -d /tmp/uuid-XXXXXX`
TYPE=`uname -r | cut -d '-' -f 3`

if echo "$1" | grep ".lz$" >/dev/null; then
	COMPRESSOR="lzma"
	SUFFIX=".lz"
elif echo "$1" | grep ".gz$" >/dev/null; then
	COMPRESSOR="gzip"
	SUFFIX=".gz"
else
	echo "Unsupported archive type."
	exit 2
fi
if [ -z "$2" ] || [ ! -d "$2" ] || [ "$2" = "." ]; then
	COMPRESS_DIR="$CWD"
else
	COMPRESS_DIR="$2"
fi

if [ -z "$3" ] || [ ! -d "$3" ] || [ "$3" = "." ]; then
	CASPERDIR="$CWD"
else
	CASPERDIR="$3"
fi

cd "$TEMPDIR"
$COMPRESSOR -cd "$1" -S "$SUFFIX" | cpio -id
uuidgen -r > conf/uuid.conf
find . | cpio --quiet --dereference -o -H newc | $COMPRESSOR -9c > "$COMPRESS_DIR/initrd$SUFFIX"
if [ "$(ls "$CASPERDIR/casper-uuid"-* >/dev/null 2>&1 | wc -l)" = 1 ]; then
    cp conf/uuid.conf "$CASPERDIR/casper-uuid"-*
else
	cp conf/uuid.conf "$CASPERDIR/casper-uuid-$TYPE"
fi
cd "$CWD"
rm -rf "$TEMPDIR"
