libuuu/sparse_format.h

   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
  17 #ifndef _LIBSPARSE_SPARSE_FORMAT_H_
  18 #define _LIBSPARSE_SPARSE_FORMAT_H_
  19
  20 #include <cstdint>
  21
  22 typedef uint32_t __le32;
  23 typedef uint16_t __le16;
  24
  25 #pragma pack(1)
  26
  27 typedef struct sparse_header {
  28     __le32 magic;               /* 0xed26ff3a */
  29     __le16 major_version;       /* (0x1) - reject images with higher major versions */
  30     __le16 minor_version;       /* (0x0) - allow images with higher minor versions */
  31     __le16 file_hdr_sz;         /* 28 bytes for first revision of the file format */
  32     __le16 chunk_hdr_sz;        /* 12 bytes for first revision of the file format */
  33     __le32 blk_sz;              /* block size in bytes, must be a multiple of 4 (4096) */
  34     __le32 total_blks;          /* total blocks in the non-sparse output image */
  35     __le32 total_chunks;        /* total chunks in the sparse input image */
  36     __le32 image_checksum;      /* CRC32 checksum of the original data, counting "don't care" */
  37     /* as 0. Standard 802.3 polynomial, use a Public Domain */
  38     /* table implementation */
  39 } sparse_header_t;
  40
  41 #define SPARSE_HEADER_MAGIC     0xed26ff3a
  42
  43 #define CHUNK_TYPE_RAW          0xCAC1
  44 #define CHUNK_TYPE_FILL         0xCAC2
  45 #define CHUNK_TYPE_DONT_CARE    0xCAC3
  46 #define CHUNK_TYPE_CRC32    0xCAC4
  47
  48 typedef struct chunk_header {
  49     __le16 chunk_type;          /* 0xCAC1 -> raw; 0xCAC2 -> fill; 0xCAC3 -> don't care */
  50     __le16 reserved1;
  51     __le32 chunk_sz;            /* in blocks in output image */
  52     __le32 total_sz;            /* in bytes of chunk input file including chunk header and data */
  53 } chunk_header_t;
  54
  55 /* Following a Raw or Fill or CRC32 chunk is data.
  56  *  For a Raw chunk, it's the data in chunk_sz * blk_sz.
  57  *  For a Fill chunk, it's 4 bytes of the fill data.
  58  *  For a CRC32 chunk, it's 4 bytes of CRC32
  59  */
  60 #pragma pack()
  61
  62 #endif