sparse_format.h revision 8642b7fba54727a38f751516bcdc452fb09ef610 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17typedef struct sparse_header {
18  __le32	magic;		/* 0xed26ff3a */
19  __le16	major_version;	/* (0x1) - reject images with higher major versions */
20  __le16	minor_version;	/* (0x0) - allow images with higer minor versions */
21  __le16	file_hdr_sz;	/* 28 bytes for first revision of the file format */
22  __le16	chunk_hdr_sz;	/* 12 bytes for first revision of the file format */
23  __le32	blk_sz;		/* block size in bytes, must be a multiple of 4 (4096) */
24  __le32	total_blks;	/* total blocks in the non-sparse output image */
25  __le32	total_chunks;	/* total chunks in the sparse input image */
26  __le32	image_checksum; /* CRC32 checksum of the original data, counting "don't care" */
27				/* as 0. Standard 802.3 polynomial, use a Public Domain */
28				/* table implementation */
29} sparse_header_t;
30
31#define SPARSE_HEADER_MAGIC	0xed26ff3a
32
33#define CHUNK_TYPE_RAW		0xCAC1
34#define CHUNK_TYPE_FILL		0xCAC2
35#define CHUNK_TYPE_DONT_CARE	0xCAC3
36
37typedef struct chunk_header {
38  __le16	chunk_type;	/* 0xCAC1 -> raw; 0xCAC2 -> fill; 0xCAC3 -> don't care */
39  __le16	reserved1;
40  __le32	chunk_sz;	/* in blocks in output image */
41  __le32	total_sz;	/* in bytes of chunk input file including chunk header and data */
42} chunk_header_t;
43
44/* Following a Raw or Fill chunk is data.  For a Raw chunk, it's the data in chunk_sz * blk_sz.
45 *  For a Fill chunk, it's 4 bytes of the fill data.
46 */
47
48