/* * Copyright (C) 2010 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ typedef struct sparse_header { uint32_t magic; /* 0xed26ff3a */ uint16_t major_version; /* (0x1) - reject images with higher major versions */ uint16_t minor_version; /* (0x0) - allow images with higer minor versions */ uint16_t file_hdr_sz; /* 28 bytes for first revision of the file format */ uint16_t chunk_hdr_sz; /* 12 bytes for first revision of the file format */ uint32_t blk_sz; /* block size in bytes, must be a multiple of 4 (4096) */ uint32_t total_blks; /* total blocks in the non-sparse output image */ uint32_t total_chunks; /* total chunks in the sparse input image */ uint32_t image_checksum; /* CRC32 checksum of the original data, counting "don't care" */ /* as 0. Standard 802.3 polynomial, use a Public Domain */ /* table implementation */ } sparse_header_t; #define SPARSE_HEADER_MAGIC 0xed26ff3a #define CHUNK_TYPE_RAW 0xCAC1 #define CHUNK_TYPE_FILL 0xCAC2 #define CHUNK_TYPE_DONT_CARE 0xCAC3 #define CHUNK_TYPE_CRC 0xCAC4 typedef struct 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; /* Following a Raw or Fill chunk is data. For a Raw chunk, it's the data in chunk_sz * blk_sz. * For a Fill chunk, it's 4 bytes of the fill data. */