1#!/bin/sh 2# 3# Copyright (C) 2011 OpenWrt.org 4# 5# This is free software, licensed under the GNU General Public License v2. 6# See /LICENSE for more information. 7# 8 9# Write image header followed by all specified files 10# The header is padded to 64k, format is: 11# CE magic word ("Combined Extended Image") (2 bytes) 12# <CE_VERSION> file format version field (2 bytes) 13# <TYPE> short description of the target device (32 bytes) 14# <NUM FILES> number of files following the header (2 byte) 15# <file1_name> name of the first file (32 bytes) 16# <file1_length> length of the first file encoded as zero padded 8 digit hex (8 bytes) 17# <file1_md5> md5 checksum of the first file (32 bytes) 18# <fileN_name> name of the Nth file (32 bytes) 19# <fileN_length> length of the Nth file encoded as zero padded 8 digit hex (8 bytes) 20# <fileN_md5> md5 checksum of the Nth file (32 bytes) 21 22## version history 23# * version 1: initial file format with num files / name / length / md5 checksum 24 25ME="${0##*/}" 26 27usage() { 28 echo "Usage: $ME <type> <ext filename> <file1> <filename1> [<file2> <filename2> <fileN> <filenameN>]" 29 [ "$IMG_OUT" ] && rm -f "$IMG_OUT" 30 exit 1 31} 32 33[ "$#" -lt 4 ] && usage 34 35CE_VERSION=1 36IMG_TYPE=$1; shift 37IMG_OUT=$1; shift 38FILE_NUM=$(($# / 2)) 39FILES="" 40 41printf "CE%02x%-32s%02x" $CE_VERSION "$IMG_TYPE" $FILE_NUM > $IMG_OUT 42 43while [ "$#" -gt 1 ] 44 do 45 file=$1 46 filename=$2 47 48 [ ! -f "$file" ] && echo "$ME: Not a valid file: $file" && usage 49 FILES="$FILES $file" 50 md5=$(cat "$file" | md5sum -) 51 printf "%-32s%08x%32s" "$filename" $(stat -c "%s" "$file") "${md5%% *}" >> $IMG_OUT 52 shift 2 53 done 54 55[ "$#" -eq 1 ] && echo "$ME: Filename not specified: $1" && usage 56 57mv $IMG_OUT $IMG_OUT.tmp 58dd if="$IMG_OUT.tmp" of="$IMG_OUT" bs=65536 conv=sync 2>/dev/null 59rm $IMG_OUT.tmp 60 61cat $FILES >> $IMG_OUT 62