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/* SPDX-License-Identifier: Apache-2.0 */
/*
* Copyright (C) 2010 The Android Open Source Project
*/
#ifndef __SPARSE_H__
#define __SPARSE_H__
#include <stdint.h>
#include <stdio.h>
typedef struct __attribute__((__packed__)) sparse_header {
/* 0xed26ff3a */
uint32_t magic;
/* (0x1) - reject images with higher major versions */
uint16_t major_version;
/* (0x0) - allow images with higer minor versions */
uint16_t minor_version;
/* 28 bytes for first revision of the file format */
uint16_t file_hdr_sz;
/* 12 bytes for first revision of the file format */
uint16_t chunk_hdr_sz;
/* block size in bytes, must be a multiple of 4 (4096) */
uint32_t blk_sz;
/* total blocks in the non-sparse output image */
uint32_t total_blks;
/* total chunks in the sparse input image */
uint32_t total_chunks;
/*
* CRC32 checksum of the original data, counting "don't care"
* as 0. Standard 802.3 polynomial, use a Public Domain
* table implementation
*/
uint32_t image_checksum;
} sparse_header_t;
#define SPARSE_HEADER_MAGIC 0xed26ff3a
#define SPARSE_HEADER_MAJOR_VER 0x0001
#define SPARSE_HEADER_MINOR_VER 0x0000
typedef struct __attribute__((__packed__)) chunk_header {
uint16_t chunk_type; /* 0xCAC1 -> raw; 0xCAC2 -> fill; 0xCAC3 -> don't care */
uint16_t reserved1;
uint32_t chunk_sz; /* in blocks in output image */
uint32_t total_sz; /* in bytes of chunk input file including chunk header and data */
} chunk_header_t;
#define CHUNK_TYPE_RAW 0xCAC1
#define CHUNK_TYPE_FILL 0xCAC2
#define CHUNK_TYPE_DONT_CARE 0xCAC3
/*
* Parses the sparse image header from the file descriptor.
* Returns 0 on success, or an error code otherwise.
*/
int sparse_header_parse(int fd, sparse_header_t *sparse_header);
/*
* Parses the sparse image chunk header from the file descriptor.
* Sets the chunk size, and value or offset based on the parsed data.
* Returns the chunk type on success, or an error code otherwise.
*/
int sparse_chunk_header_parse(int fd, sparse_header_t *sparse_header,
uint64_t *chunk_size,
uint32_t *value, off_t *offset);
#endif
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