delta_diff_utils.h revision e9f9661e99917c9b33e10fb6c4f10979b13f572b
1// 2// Copyright (C) 2015 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 UPDATE_ENGINE_PAYLOAD_GENERATOR_DELTA_DIFF_UTILS_H_ 18#define UPDATE_ENGINE_PAYLOAD_GENERATOR_DELTA_DIFF_UTILS_H_ 19 20#include <string> 21#include <vector> 22 23#include <brillo/secure_blob.h> 24 25#include "update_engine/payload_generator/annotated_operation.h" 26#include "update_engine/payload_generator/extent_ranges.h" 27#include "update_engine/payload_generator/payload_generation_config.h" 28#include "update_engine/update_metadata.pb.h" 29 30namespace chromeos_update_engine { 31 32namespace diff_utils { 33 34// Create operations in |aops| to produce all the blocks in the |new_part| 35// partition using the filesystem opened in that PartitionConfig. 36// It uses the files reported by the filesystem in |old_part| and the data 37// blocks in that partition (if available) to determine the best way to compress 38// the new files (REPLACE, REPLACE_BZ, COPY, BSDIFF) and writes any necessary 39// data to |blob_file|. |hard_chunk_blocks| and |soft_chunk_blocks| are the hard 40// and soft chunk limits in number of blocks respectively. The soft chunk limit 41// is used to split MOVE and SOURCE_COPY operations and REPLACE_BZ of zeroed 42// blocks, while the hard limit is used to split a file when generating other 43// operations. A value of -1 in |hard_chunk_blocks| means whole files. 44bool DeltaReadPartition(std::vector<AnnotatedOperation>* aops, 45 const PartitionConfig& old_part, 46 const PartitionConfig& new_part, 47 ssize_t hard_chunk_blocks, 48 size_t soft_chunk_blocks, 49 const PayloadVersion& version, 50 BlobFileWriter* blob_file); 51 52// Create operations in |aops| for identical blocks that moved around in the old 53// and new partition and also handle zeroed blocks. The old and new partition 54// are stored in the |old_part| and |new_part| files and have |old_num_blocks| 55// and |new_num_blocks| respectively. The maximum operation size is 56// |chunk_blocks| blocks, or unlimited if |chunk_blocks| is -1. The blobs of the 57// produced operations are stored in the |blob_file|. 58// The collections |old_visited_blocks| and |new_visited_blocks| state what 59// blocks already have operations reading or writing them and only operations 60// for unvisited blocks are produced by this function updating both collections 61// with the used blocks. 62bool DeltaMovedAndZeroBlocks(std::vector<AnnotatedOperation>* aops, 63 const std::string& old_part, 64 const std::string& new_part, 65 size_t old_num_blocks, 66 size_t new_num_blocks, 67 ssize_t chunk_blocks, 68 const PayloadVersion& version, 69 BlobFileWriter* blob_file, 70 ExtentRanges* old_visited_blocks, 71 ExtentRanges* new_visited_blocks); 72 73// For a given file |name| append operations to |aops| to produce it in the 74// |new_part|. The file will be split in chunks of |chunk_blocks| blocks each 75// or treated as a single chunk if |chunk_blocks| is -1. The file data is 76// stored in |new_part| in the blocks described by |new_extents| and, if it 77// exists, the old version exists in |old_part| in the blocks described by 78// |old_extents|. The operations added to |aops| reference the data blob 79// in the |blob_file|. Returns true on success. 80bool DeltaReadFile(std::vector<AnnotatedOperation>* aops, 81 const std::string& old_part, 82 const std::string& new_part, 83 const std::vector<Extent>& old_extents, 84 const std::vector<Extent>& new_extents, 85 const std::string& name, 86 ssize_t chunk_blocks, 87 const PayloadVersion& version, 88 BlobFileWriter* blob_file); 89 90// Reads the blocks |old_extents| from |old_part| (if it exists) and the 91// |new_extents| from |new_part| and determines the smallest way to encode 92// this |new_extents| for the diff. It stores necessary data in |out_data| and 93// fills in |out_op|. If there's no change in old and new files, it creates a 94// MOVE or SOURCE_COPY operation. If there is a change, the smallest of the 95// operations allowed in the given |version| (REPLACE, REPLACE_BZ, BSDIFF, 96// SOURCE_BSDIFF, or PUFFDIFF) wins. 97// |new_extents| must not be empty. Returns true on success. 98bool ReadExtentsToDiff(const std::string& old_part, 99 const std::string& new_part, 100 const std::vector<Extent>& old_extents, 101 const std::vector<Extent>& new_extents, 102 const PayloadVersion& version, 103 brillo::Blob* out_data, 104 InstallOperation* out_op); 105 106// Generates the best allowed full operation to produce |new_data|. The allowed 107// operations are based on |payload_version|. The operation blob will be stored 108// in |out_blob| and the resulting operation type in |out_type|. Returns whether 109// a valid full operation was generated. 110bool GenerateBestFullOperation(const brillo::Blob& new_data, 111 const PayloadVersion& version, 112 brillo::Blob* out_blob, 113 InstallOperation_Type* out_type); 114 115// Returns whether op_type is one of the REPLACE full operations. 116bool IsAReplaceOperation(InstallOperation_Type op_type); 117 118// Returns true if |op| is a no-op operation that doesn't do any useful work 119// (e.g., a move operation that copies blocks onto themselves). 120bool IsNoopOperation(const InstallOperation& op); 121 122// Filters all the operations that are no-op, maintaining the relative order 123// of the rest of the operations. 124void FilterNoopOperations(std::vector<AnnotatedOperation>* ops); 125 126bool InitializePartitionInfo(const PartitionConfig& partition, 127 PartitionInfo* info); 128 129// Compare two AnnotatedOperations by the start block of the first Extent in 130// their destination extents. 131bool CompareAopsByDestination(AnnotatedOperation first_aop, 132 AnnotatedOperation second_aop); 133 134// Returns whether the filesystem is an ext[234] filesystem. In case of failure, 135// such as if the file |device| doesn't exists or can't be read, it returns 136// false. 137bool IsExtFilesystem(const std::string& device); 138 139// Returns the max number of threads to process the files(chunks) in parallel. 140size_t GetMaxThreads(); 141 142} // namespace diff_utils 143 144} // namespace chromeos_update_engine 145 146#endif // UPDATE_ENGINE_PAYLOAD_GENERATOR_DELTA_DIFF_UTILS_H_ 147