scripts/combined-ext-image.sh

   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
  25 set -e
  26
  27 ME="${0##*/}"
  28
  29 usage() {
  30         echo "Usage: $ME <type> <ext filename> <file1> <filename1> [<file2> <filename2> <fileN> <filenameN>]"
  31         [ "$IMG_OUT" ] && rm -f "$IMG_OUT"
  32         exit 1
  33 }
  34
  35 [ "$#" -lt 4 ] && usage
  36
  37 CE_VERSION=1
  38 IMG_TYPE=$1; shift
  39 IMG_OUT=$1; shift
  40 FILE_NUM=$(($# / 2))
  41 FILES=""
  42
  43 tmpdir="$( mktemp -d 2> /dev/null )"
  44 if [ -z "$tmpdir" ]; then
  45         # try OSX signature
  46         tmpdir="$( mktemp -t 'ubitmp' -d )"
  47 fi
  48
  49 if [ -z "$tmpdir" ]; then
  50         exit 1
  51 fi
  52
  53 trap "rm -rf $tmpdir" EXIT
  54
  55 IMG_TMP_OUT="${tmpdir}/out"
  56
  57 printf "CE%02x%-32s%02x" $CE_VERSION "$IMG_TYPE" $FILE_NUM > "${IMG_TMP_OUT}"
  58
  59 while [ "$#" -gt 1 ]
  60    do
  61       file=$1
  62       filename=$2
  63
  64       [ ! -f "$file" ] && echo "$ME: Not a valid file: $file" && usage
  65       FILES="$FILES $file"
  66       md5=$(mkhash md5 "$file")
  67       printf "%-32s%08x%32s" "$filename" $(stat -c "%s" "$file") "${md5%% *}" >> "${IMG_TMP_OUT}"
  68       shift 2
  69    done
  70
  71 [ "$#" -eq 1 ] && echo "$ME: Filename not specified: $1" && usage
  72
  73 mv "${IMG_TMP_OUT}" "${IMG_TMP_OUT}".tmp
  74 dd if="${IMG_TMP_OUT}.tmp" of="${IMG_TMP_OUT}" bs=65536 conv=sync 2>/dev/null
  75 rm "${IMG_TMP_OUT}".tmp
  76
  77 cat $FILES >> "${IMG_TMP_OUT}"
  78 cp "${IMG_TMP_OUT}" "${IMG_OUT}"