ar71xx: add support for TP-Link WBS210/510
[openwrt/openwrt.git] / scripts / pad_image
1 #!/usr/bin/env bash
2
3 function usage {
4 echo "Usage: prepare_image image_type kernel_image rootfs_image header_size"
5 echo "Padd root and kernel image to the correct size and append the jffs2 start marker as needed"
6 exit 1
7 }
8
9 function pad_file {
10 echo "Padding $1 to size $2"
11 dd if=$1 of=$1.paddingtempfile bs=$2 count=1 conv=sync &> /dev/null
12 mv $1.paddingtempfile $1
13 }
14
15 #filesize filestart padding
16 function calc_pad {
17 [ $((($1 + $2) & ($3 - 1))) == 0 ] && {
18 echo $1
19 return 0
20 }
21 echo $(((($1 + $2) | ($3 - 1)) + 1 - $2))
22 }
23
24 function prep_squash {
25 echo "kernel_size: $kernel_size"
26 echo "header_size: $header_size"
27 kernel_pad_size=$(calc_pad $kernel_size $header_size 32)
28 kernel_end=$(($header_size + $kernel_pad_size))
29 pad_file $kernel_image $kernel_pad_size
30
31 #4k
32 rootfs_pad_size=$(calc_pad $rootfs_size $kernel_end 4096)
33 pad_file $rootfs_image $rootfs_pad_size
34 echo -ne '\xde\xad\xc0\xde' >> $rootfs_image
35
36 #8k
37 rootfs_pad_size=$(calc_pad $rootfs_size $kernel_end 8192)
38 [ $rootfs_pad_size == rootfs_old_padsize ] || {
39 pad_file $rootfs_image $rootfs_pad_size
40 rootfs_old_padsize=$rootfs_pad_size
41 echo -ne '\xde\xad\xc0\xde' >> $rootfs_image
42 }
43
44 #64k
45 rootfs_pad_size=$(calc_pad $rootfs_size $kernel_end 65536)
46 [ $rootfs_pad_size == rootfs_old_padsize ] || {
47 pad_file $rootfs_image $rootfs_pad_size
48 rootfs_old_padsize=$rootfs_pad_size
49 echo -ne '\xde\xad\xc0\xde' >> $rootfs_image
50 }
51
52 #128k
53 rootfs_pad_size=$(calc_pad $rootfs_size $kernel_end 131072)
54 [ $rootfs_pad_size == rootfs_old_padsize ] || {
55 pad_file $rootfs_image $rootfs_pad_size
56 rootfs_old_padsize=$rootfs_pad_size
57 echo -ne '\xde\xad\xc0\xde' >> $rootfs_image
58 }
59
60 }
61
62 function prep_jffs2 {
63 kernel_pad_size=$(calc_pad $kernel_size $header_size $1)
64 pad_file $kernel_image $kernel_pad_size
65 }
66
67 image_type=$1
68 kernel_image=$2
69 rootfs_image=$3
70 header_size=$4
71
72 if [ -z "$image_type" ] || [ -z "$rootfs_image" ] || [ -z "$kernel_image" ] || [ -z "$header_size" ]; then
73 usage
74 fi
75
76 if [ ! -e "$rootfs_image" ] || [ -z "$kernel_image" ]; then
77 echo "input file not found"
78 exit 1
79 fi
80
81 kernel_size=$(stat -c "%s" "$kernel_image")
82 rootfs_size=$(stat -c "%s" "$rootfs_image")
83
84 if [ $kernel_size == 0 ] || [ $rootfs_size == 0 ]; then
85 echo "kernel or rootfs empty"
86 exit 1
87 fi
88
89 case $image_type in
90 squashfs )
91 prep_squash ;;
92 jffs2-64k )
93 prep_jffs2 65536 ;;
94 jffs2-128k )
95 prep_jffs2 131072 ;;
96 * )
97 echo "Unknown image type"
98 exit 1 ;;
99 esac
100