scripts/combined-ext-image.sh


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#!/bin/sh
#
# Copyright (C) 2011 OpenWrt.org
#
# This is free software, licensed under the GNU General Public License v2.
# See /LICENSE for more information.
#

# Write image header followed by all specified files
# The header is padded to 64k, format is:
#  CE               magic word ("Combined Extended Image") (2 bytes)
#  <CE_VERSION>     file format version field (2 bytes) 
#  <TYPE>           short description of the target device (32 bytes)
#  <NUM FILES>      number of files following the header (2 byte)
#  <file1_name>     name of the first file (32 bytes)
#  <file1_length>   length of the first file encoded as zero padded 8 digit hex (8 bytes)
#  <file1_md5>      md5 checksum of the first file (32 bytes)
#  <fileN_name>     name of the Nth file (32 bytes)
#  <fileN_length>   length of the Nth file encoded as zero padded 8 digit hex (8 bytes)
#  <fileN_md5>      md5 checksum of the Nth file (32 bytes)

## version history
# * version 1: initial file format with num files / name / length / md5 checksum 

ME="${0##*/}"

usage() {
	echo "Usage: $ME <type> <ext filename> <file1> <filename1> [<file2> <filename2> <fileN> <filenameN>]"
	[ "$IMG_OUT" ] && rm -f "$IMG_OUT"
	exit 1
}

[ "$#" -lt 4 ] && usage

CE_VERSION=1
IMG_TYPE=$1; shift
IMG_OUT=$1; shift