1#!/bin/sh
2# Copyright (C) Martin Schlemmer <azarah@nosferatu.za.org>
3# Copyright (C) 2006 Sam Ravnborg <sam@ravnborg.org>
4#
5# Released under the terms of the GNU GPL
6#
7# Generate a cpio packed initramfs. It uses gen_init_cpio to generate
8# the cpio archive, and then compresses it.
9# The script may also be used to generate the inputfile used for gen_init_cpio
10# This script assumes that gen_init_cpio is located in usr/ directory
11
12# error out on errors
13set -e
14
15usage() {
16cat << EOF
17Usage:
18$0 [-o <file>] [-u <uid>] [-g <gid>] {-d | <cpio_source>} ...
19	-o <file>      Create compressed initramfs file named <file> using
20		       gen_init_cpio and compressor depending on the extension
21	-u <uid>       User ID to map to user ID 0 (root).
22		       <uid> is only meaningful if <cpio_source> is a
23		       directory.  "squash" forces all files to uid 0.
24	-g <gid>       Group ID to map to group ID 0 (root).
25		       <gid> is only meaningful if <cpio_source> is a
26		       directory.  "squash" forces all files to gid 0.
27	<cpio_source>  File list or directory for cpio archive.
28		       If <cpio_source> is a .cpio file it will be used
29		       as direct input to initramfs.
30	-d             Output the default cpio list.
31
32All options except -o and -l may be repeated and are interpreted
33sequentially and immediately.  -u and -g states are preserved across
34<cpio_source> options so an explicit "-u 0 -g 0" is required
35to reset the root/group mapping.
36EOF
37}
38
39# awk style field access
40# $1 - field number; rest is argument string
41field() {
42	shift $1 ; echo $1
43}
44
45list_default_initramfs() {
46	# echo usr/kinit/kinit
47	:
48}
49
50default_initramfs() {
51	cat <<-EOF >> ${output}
52		# This is a very simple, default initramfs
53
54		dir /dev 0755 0 0
55		nod /dev/console 0600 0 0 c 5 1
56		dir /root 0700 0 0
57		# file /kinit usr/kinit/kinit 0755 0 0
58		# slink /init kinit 0755 0 0
59	EOF
60}
61
62filetype() {
63	local argv1="$1"
64
65	# symlink test must come before file test
66	if [ -L "${argv1}" ]; then
67		echo "slink"
68	elif [ -f "${argv1}" ]; then
69		echo "file"
70	elif [ -d "${argv1}" ]; then
71		echo "dir"
72	elif [ -b "${argv1}" -o -c "${argv1}" ]; then
73		echo "nod"
74	elif [ -p "${argv1}" ]; then
75		echo "pipe"
76	elif [ -S "${argv1}" ]; then
77		echo "sock"
78	else
79		echo "invalid"
80	fi
81	return 0
82}
83
84list_print_mtime() {
85	:
86}
87
88print_mtime() {
89	local my_mtime="0"
90
91	if [ -e "$1" ]; then
92		my_mtime=$(find "$1" -printf "%T@\n" | sort -r | head -n 1)
93	fi
94
95	echo "# Last modified: ${my_mtime}" >> ${output}
96	echo "" >> ${output}
97}
98
99list_parse() {
100	if [ -L "$1" ]; then
101		return
102	fi
103	echo "$1" | sed 's/:/\\:/g; s/$/ \\/'
104}
105
106# for each file print a line in following format
107# <filetype> <name> <path to file> <octal mode> <uid> <gid>
108# for links, devices etc the format differs. See gen_init_cpio for details
109parse() {
110	local location="$1"
111	local name="/${location#${srcdir}}"
112	# change '//' into '/'
113	name=$(echo "$name" | sed -e 's://*:/:g')
114	local mode="$2"
115	local uid="$3"
116	local gid="$4"
117	local ftype=$(filetype "${location}")
118	# remap uid/gid to 0 if necessary
119	[ "$root_uid" = "squash" ] && uid=0 || [ "$uid" -eq "$root_uid" ] && uid=0
120	[ "$root_gid" = "squash" ] && gid=0 || [ "$gid" -eq "$root_gid" ] && gid=0
121	local str="${mode} ${uid} ${gid}"
122
123	[ "${ftype}" = "invalid" ] && return 0
124	[ "${location}" = "${srcdir}" ] && return 0
125
126	case "${ftype}" in
127		"file")
128			str="${ftype} ${name} ${location} ${str}"
129			;;
130		"nod")
131			local dev=`LC_ALL=C ls -l "${location}"`
132			local maj=`field 5 ${dev}`
133			local min=`field 6 ${dev}`
134			maj=${maj%,}
135
136			[ -b "${location}" ] && dev="b" || dev="c"
137
138			str="${ftype} ${name} ${str} ${dev} ${maj} ${min}"
139			;;
140		"slink")
141			local target=`readlink "${location}"`
142			str="${ftype} ${name} ${target} ${str}"
143			;;
144		*)
145			str="${ftype} ${name} ${str}"
146			;;
147	esac
148
149	echo "${str}" >> ${output}
150
151	return 0
152}
153
154unknown_option() {
155	printf "ERROR: unknown option \"$arg\"\n" >&2
156	printf "If the filename validly begins with '-', " >&2
157	printf "then it must be prefixed\n" >&2
158	printf "by './' so that it won't be interpreted as an option." >&2
159	printf "\n" >&2
160	usage >&2
161	exit 1
162}
163
164list_header() {
165	:
166}
167
168header() {
169	printf "\n#####################\n# $1\n" >> ${output}
170}
171
172# process one directory (incl sub-directories)
173dir_filelist() {
174	${dep_list}header "$1"
175
176	srcdir=$(echo "$1" | sed -e 's://*:/:g')
177	dirlist=$(find "${srcdir}" -printf "%p %m %U %G\n" | LANG=C sort)
178
179	# If $dirlist is only one line, then the directory is empty
180	if [  "$(echo "${dirlist}" | wc -l)" -gt 1 ]; then
181		${dep_list}print_mtime "$1"
182
183		echo "${dirlist}" | \
184		while read x; do
185			${dep_list}parse ${x}
186		done
187	fi
188}
189
190# if only one file is specified and it is .cpio file then use it direct as fs
191# if a directory is specified then add all files in given direcotry to fs
192# if a regular file is specified assume it is in gen_initramfs format
193input_file() {
194	source="$1"
195	if [ -f "$1" ]; then
196		${dep_list}header "$1"
197		is_cpio="$(echo "$1" | sed 's/^.*\.cpio\(\..*\)\{0,1\}/cpio/')"
198		if [ $2 -eq 0 -a ${is_cpio} = "cpio" ]; then
199			cpio_file=$1
200			echo "$1" | grep -q '^.*\.cpio\..*' && is_cpio_compressed="compressed"
201			[ ! -z ${dep_list} ] && echo "$1"
202			return 0
203		fi
204		if [ -z ${dep_list} ]; then
205			print_mtime "$1" >> ${output}
206			cat "$1"         >> ${output}
207		else
208		        echo "$1 \\"
209			cat "$1" | while read type dir file perm ; do
210				if [ "$type" = "file" ]; then
211					echo "$file \\";
212				fi
213			done
214		fi
215	elif [ -d "$1" ]; then
216		dir_filelist "$1"
217	else
218		echo "  ${prog}: Cannot open '$1'" >&2
219		exit 1
220	fi
221}
222
223prog=$0
224root_uid=0
225root_gid=0
226dep_list=
227cpio_file=
228cpio_list=
229output="/dev/stdout"
230output_file=""
231is_cpio_compressed=
232compr="gzip -n -9 -f"
233
234arg="$1"
235case "$arg" in
236	"-l")	# files included in initramfs - used by kbuild
237		dep_list="list_"
238		echo "deps_initramfs := $0 \\"
239		shift
240		;;
241	"-o")	# generate compressed cpio image named $1
242		shift
243		output_file="$1"
244		cpio_list="$(mktemp ${TMPDIR:-/tmp}/cpiolist.XXXXXX)"
245		output=${cpio_list}
246		echo "$output_file" | grep -q "\.gz$" \
247                && [ -x "`which gzip 2> /dev/null`" ] \
248                && compr="gzip -n -9 -f"
249		echo "$output_file" | grep -q "\.bz2$" \
250                && [ -x "`which bzip2 2> /dev/null`" ] \
251                && compr="bzip2 -9 -f"
252		echo "$output_file" | grep -q "\.lzma$" \
253                && [ -x "`which lzma 2> /dev/null`" ] \
254                && compr="lzma -9 -f"
255		echo "$output_file" | grep -q "\.xz$" \
256                && [ -x "`which xz 2> /dev/null`" ] \
257                && compr="xz --check=crc32 --lzma2=dict=1MiB"
258		echo "$output_file" | grep -q "\.lzo$" \
259                && [ -x "`which lzop 2> /dev/null`" ] \
260                && compr="lzop -9 -f"
261		echo "$output_file" | grep -q "\.lz4$" \
262                && [ -x "`which lz4 2> /dev/null`" ] \
263                && compr="lz4 -l -9 -f"
264		echo "$output_file" | grep -q "\.cpio$" && compr="cat"
265		shift
266		;;
267esac
268while [ $# -gt 0 ]; do
269	arg="$1"
270	shift
271	case "$arg" in
272		"-u")	# map $1 to uid=0 (root)
273			root_uid="$1"
274			[ "$root_uid" = "-1" ] && root_uid=$(id -u || echo 0)
275			shift
276			;;
277		"-g")	# map $1 to gid=0 (root)
278			root_gid="$1"
279			[ "$root_gid" = "-1" ] && root_gid=$(id -g || echo 0)
280			shift
281			;;
282		"-d")	# display default initramfs list
283			default_list="$arg"
284			${dep_list}default_initramfs
285			;;
286		"-h")
287			usage
288			exit 0
289			;;
290		*)
291			case "$arg" in
292				"-"*)
293					unknown_option
294					;;
295				*)	# input file/dir - process it
296					input_file "$arg" "$#"
297					;;
298			esac
299			;;
300	esac
301done
302
303# If output_file is set we will generate cpio archive and compress it
304# we are careful to delete tmp files
305if [ ! -z ${output_file} ]; then
306	if [ -z ${cpio_file} ]; then
307		timestamp=
308		if test -n "$KBUILD_BUILD_TIMESTAMP"; then
309			timestamp="$(date -d"$KBUILD_BUILD_TIMESTAMP" +%s || :)"
310			if test -n "$timestamp"; then
311				timestamp="-t $timestamp"
312			fi
313		fi
314		cpio_tfile="$(mktemp ${TMPDIR:-/tmp}/cpiofile.XXXXXX)"
315		usr/gen_init_cpio $timestamp ${cpio_list} > ${cpio_tfile}
316	else
317		cpio_tfile=${cpio_file}
318	fi
319	rm ${cpio_list}
320	if [ "${is_cpio_compressed}" = "compressed" ]; then
321		cat ${cpio_tfile} > ${output_file}
322	else
323		(cat ${cpio_tfile} | ${compr}  - > ${output_file}) \
324		|| (rm -f ${output_file} ; false)
325	fi
326	[ -z ${cpio_file} ] && rm ${cpio_tfile}
327fi
328exit 0
329