11da177e4SLinus Torvalds#!/bin/sh 27b76bfc8SDick Streefland# ---------------------------------------------------------------------- 37b76bfc8SDick Streefland# extract-ikconfig - Extract the .config file from a kernel image 47b76bfc8SDick Streefland# 57b76bfc8SDick Streefland# This will only work when the kernel was compiled with CONFIG_IKCONFIG. 67b76bfc8SDick Streefland# 77b76bfc8SDick Streefland# The obscure use of the "tr" filter is to work around older versions of 87b76bfc8SDick Streefland# "grep" that report the byte offset of the line instead of the pattern. 97b76bfc8SDick Streefland# 10*532cf290SDick Streefland# (c) 2009,2010 Dick Streefland <dick@streefland.net> 117b76bfc8SDick Streefland# Licensed under the terms of the GNU General Public License. 127b76bfc8SDick Streefland# ---------------------------------------------------------------------- 131da177e4SLinus Torvalds 147b76bfc8SDick Streeflandcf1='IKCFG_ST\037\213\010' 157b76bfc8SDick Streeflandcf2='0123456789' 161da177e4SLinus Torvalds 177b76bfc8SDick Streeflanddump_config() 181da177e4SLinus Torvalds{ 197b76bfc8SDick Streefland if pos=`tr "$cf1\n$cf2" "\n$cf2=" < "$1" | grep -abo "^$cf2"` 201da177e4SLinus Torvalds then 217b76bfc8SDick Streefland pos=${pos%%:*} 22*532cf290SDick Streefland tail -c+$(($pos+8)) "$1" | zcat > $tmp1 2> /dev/null 23*532cf290SDick Streefland if [ $? != 1 ] 24*532cf290SDick Streefland then # exit status must be 0 or 2 (trailing garbage warning) 25*532cf290SDick Streefland cat $tmp1 267b76bfc8SDick Streefland exit 0 277b76bfc8SDick Streefland fi 28*532cf290SDick Streefland fi 29*532cf290SDick Streefland} 30*532cf290SDick Streefland 31*532cf290SDick Streeflandtry_decompress() 32*532cf290SDick Streefland{ 33*532cf290SDick Streefland for pos in `tr "$1\n$2" "\n$2=" < "$img" | grep -abo "^$2"` 34*532cf290SDick Streefland do 35*532cf290SDick Streefland pos=${pos%%:*} 36*532cf290SDick Streefland tail -c+$pos "$img" | $3 > $tmp2 2> /dev/null 37*532cf290SDick Streefland dump_config $tmp2 38*532cf290SDick Streefland done 397b76bfc8SDick Streefland} 407b76bfc8SDick Streefland 417b76bfc8SDick Streefland# Check invocation: 427b76bfc8SDick Streeflandme=${0##*/} 437b76bfc8SDick Streeflandimg=$1 447b76bfc8SDick Streeflandif [ $# -ne 1 -o ! -s "$img" ] 457b76bfc8SDick Streeflandthen 467b76bfc8SDick Streefland echo "Usage: $me <kernel-image>" >&2 477b76bfc8SDick Streefland exit 2 481da177e4SLinus Torvaldsfi 491da177e4SLinus Torvalds 50*532cf290SDick Streefland# Prepare temp files: 51*532cf290SDick Streeflandtmp1=/tmp/ikconfig$$.1 52*532cf290SDick Streeflandtmp2=/tmp/ikconfig$$.2 53*532cf290SDick Streeflandtrap "rm -f $tmp1 $tmp2" 0 54*532cf290SDick Streefland 557b76bfc8SDick Streefland# Initial attempt for uncompressed images or objects: 567b76bfc8SDick Streeflanddump_config "$img" 571da177e4SLinus Torvalds 58*532cf290SDick Streefland# That didn't work, so retry after decompression. 59*532cf290SDick Streeflandtry_decompress '\037\213\010' xy gunzip 60*532cf290SDick Streeflandtry_decompress 'BZh' xy bunzip2 61*532cf290SDick Streeflandtry_decompress '\135\0\0\0' xxx unlzma 62*532cf290SDick Streeflandtry_decompress '\211\114\132' xy 'lzop -d' 631da177e4SLinus Torvalds 647b76bfc8SDick Streefland# Bail out: 657b76bfc8SDick Streeflandecho "$me: Cannot find kernel config." >&2 661da177e4SLinus Torvaldsexit 1 67