#!/bin/bash
# -*- mode: shell-script; indent-tabs-mode: nil; sh-basic-offset: 4; -*-
# ex: ts=8 sw=4 sts=4 et filetype=sh
#
# Copyright 2005-2010 Harald Hoyer <[email protected]>
# Copyright 2005-2010 Red Hat, Inc. All rights reserved.
#
# 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/>.
#

usage()
{
{
echo "Usage: ${0##*/} [options] [<initramfs file> [<filename> [<filename> [...] ]]]"
echo "Usage: ${0##*/} [options] -k <kernel version>"
echo
echo "-h, --help print a help message and exit."
echo "-s, --size sort the contents of the initramfs by size."
echo "-f, --file <filename> print the contents of <filename>."
echo "-k, --kver <kernel version> inspect the initramfs of <kernel version>."
echo
} >&2
}

sorted=0
declare -A filenames

unset POSIXLY_CORRECT
TEMP=$(getopt \
-o "shf:k:" \
--long kver: \
--long file: \
--long help \
--long size \
-- "$@")

if (( $? != 0 )); then
usage
exit 1
fi

eval set -- "$TEMP"

while (($# > 0)); do
case $1 in
-k|--kver) KERNEL_VERSION="$2"; shift;;
-f|--file) filenames[${2#/}]=1; shift;;
-s|--size) sorted=1;;
-h|--help) usage; exit 0;;
--) shift;break;;
*) usage; exit 1;;
esac
shift
done

[[ $KERNEL_VERSION ]] || KERNEL_VERSION="$(uname -r)"

if [[ $1 ]]; then
image="$1"
if ! [[ -f "$image" ]]; then
{
echo "$image does not exist"
echo
} >&2
usage
exit 1
fi
else
image="/boot/initramfs-${KERNEL_VERSION}.img"
fi

shift
while (($# > 0)); do
filenames[${1#/}]=1;
shift
done

if ! [[ -f "$image" ]]; then
{
echo "No <initramfs file> specified and the default image '$image' cannot be accessed!"
echo
} >&2
usage
exit 1
fi

read -N 6 bin < "$image"
case $bin in
$'\x1f\x8b'*)
CAT="zcat";;
BZh*)
CAT="bzcat";;
070701)
CAT="cat";;
*)
CAT="xzcat";
if echo "test"|xz|xzcat --single-stream >/dev/null 2>&1; then
CAT="xzcat --single-stream"
fi
;;
esac

ret=0

if (( ${#filenames[@]} > 0 )); then
(( ${#filenames[@]} == 1 )) && nofileinfo=1
for f in ${!filenames[@]}; do
[[ $nofileinfo ]] || echo "initramfs:/$f"
[[ $nofileinfo ]] || echo "========================================================================"
$CAT -- $image | cpio --extract --verbose --quiet --to-stdout $f 2>/dev/null
((ret+=$?))
[[ $nofileinfo ]] || echo "========================================================================"
[[ $nofileinfo ]] || echo
done
else
echo "Image: $image: $(du -h $image | while read a b; do echo $a;done)"
echo "========================================================================"
$CAT -- "$image" | cpio --extract --verbose --quiet --to-stdout -- 'dracut-*' 2>/dev/null
((ret+=$?))
echo "========================================================================"
if [ "$sorted" -eq 1 ]; then
$CAT -- "$image" | cpio --extract --verbose --quiet --list | sort -n -k5
else
$CAT -- "$image" | cpio --extract --verbose --quiet --list | sort -k9
fi
((ret+=$?))
echo "========================================================================"
fi

exit $ret