Linus Torvalds | 1da177e | 2005-04-16 22:20:36 | [diff] [blame] | 1 | #!/bin/sh |
Dick Streefland | 7b76bfc | 2009-10-06 20:35:40 | [diff] [blame] | 2 | # ---------------------------------------------------------------------- |
| 3 | # extract-ikconfig - Extract the .config file from a kernel image |
| 4 | # |
| 5 | # This will only work when the kernel was compiled with CONFIG_IKCONFIG. |
| 6 | # |
| 7 | # The obscure use of the "tr" filter is to work around older versions of |
| 8 | # "grep" that report the byte offset of the line instead of the pattern. |
| 9 | # |
Dick Streefland | 532cf29 | 2010-10-22 22:02:44 | [diff] [blame] | 10 | # (c) 2009,2010 Dick Streefland <dick@streefland.net> |
Dick Streefland | 7b76bfc | 2009-10-06 20:35:40 | [diff] [blame] | 11 | # Licensed under the terms of the GNU General Public License. |
| 12 | # ---------------------------------------------------------------------- |
Linus Torvalds | 1da177e | 2005-04-16 22:20:36 | [diff] [blame] | 13 | |
Dick Streefland | 7b76bfc | 2009-10-06 20:35:40 | [diff] [blame] | 14 | cf1='IKCFG_ST\037\213\010' |
| 15 | cf2='0123456789' |
Linus Torvalds | 1da177e | 2005-04-16 22:20:36 | [diff] [blame] | 16 | |
Dick Streefland | 7b76bfc | 2009-10-06 20:35:40 | [diff] [blame] | 17 | dump_config() |
Linus Torvalds | 1da177e | 2005-04-16 22:20:36 | [diff] [blame] | 18 | { |
Dick Streefland | 7b76bfc | 2009-10-06 20:35:40 | [diff] [blame] | 19 | if pos=`tr "$cf1\n$cf2" "\n$cf2=" < "$1" | grep -abo "^$cf2"` |
| 20 | then |
| 21 | pos=${pos%%:*} |
Dick Streefland | 532cf29 | 2010-10-22 22:02:44 | [diff] [blame] | 22 | tail -c+$(($pos+8)) "$1" | zcat > $tmp1 2> /dev/null |
| 23 | if [ $? != 1 ] |
| 24 | then # exit status must be 0 or 2 (trailing garbage warning) |
| 25 | cat $tmp1 |
| 26 | exit 0 |
| 27 | fi |
Linus Torvalds | 1da177e | 2005-04-16 22:20:36 | [diff] [blame] | 28 | fi |
Dick Streefland | 532cf29 | 2010-10-22 22:02:44 | [diff] [blame] | 29 | } |
| 30 | |
| 31 | try_decompress() |
| 32 | { |
| 33 | for pos in `tr "$1\n$2" "\n$2=" < "$img" | grep -abo "^$2"` |
| 34 | do |
| 35 | pos=${pos%%:*} |
| 36 | tail -c+$pos "$img" | $3 > $tmp2 2> /dev/null |
| 37 | dump_config $tmp2 |
| 38 | done |
Linus Torvalds | 1da177e | 2005-04-16 22:20:36 | [diff] [blame] | 39 | } |
| 40 | |
Dick Streefland | 7b76bfc | 2009-10-06 20:35:40 | [diff] [blame] | 41 | # Check invocation: |
| 42 | me=${0##*/} |
| 43 | img=$1 |
| 44 | if [ $# -ne 1 -o ! -s "$img" ] |
Linus Torvalds | 1da177e | 2005-04-16 22:20:36 | [diff] [blame] | 45 | then |
Dick Streefland | 7b76bfc | 2009-10-06 20:35:40 | [diff] [blame] | 46 | echo "Usage: $me <kernel-image>" >&2 |
| 47 | exit 2 |
Linus Torvalds | 1da177e | 2005-04-16 22:20:36 | [diff] [blame] | 48 | fi |
| 49 | |
Dick Streefland | 532cf29 | 2010-10-22 22:02:44 | [diff] [blame] | 50 | # Prepare temp files: |
| 51 | tmp1=/tmp/ikconfig$$.1 |
| 52 | tmp2=/tmp/ikconfig$$.2 |
| 53 | trap "rm -f $tmp1 $tmp2" 0 |
| 54 | |
Dick Streefland | 7b76bfc | 2009-10-06 20:35:40 | [diff] [blame] | 55 | # Initial attempt for uncompressed images or objects: |
| 56 | dump_config "$img" |
Linus Torvalds | 1da177e | 2005-04-16 22:20:36 | [diff] [blame] | 57 | |
Dick Streefland | 532cf29 | 2010-10-22 22:02:44 | [diff] [blame] | 58 | # That didn't work, so retry after decompression. |
Dick Streefland | ab94e46 | 2011-01-23 23:44:57 | [diff] [blame] | 59 | try_decompress '\037\213\010' xy gunzip |
| 60 | try_decompress '\3757zXZ\000' abcde unxz |
| 61 | try_decompress 'BZh' xy bunzip2 |
| 62 | try_decompress '\135\0\0\0' xxx unlzma |
| 63 | try_decompress '\211\114\132' xy 'lzop -d' |
Alex Pilon | 99b2cdd | 2015-04-14 04:38:33 | [diff] [blame] | 64 | try_decompress '\002\041\114\030' xyy 'lz4 -d -l' |
Linus Torvalds | 1da177e | 2005-04-16 22:20:36 | [diff] [blame] | 65 | |
Dick Streefland | 7b76bfc | 2009-10-06 20:35:40 | [diff] [blame] | 66 | # Bail out: |
| 67 | echo "$me: Cannot find kernel config." >&2 |
Linus Torvalds | 1da177e | 2005-04-16 22:20:36 | [diff] [blame] | 68 | exit 1 |