| // |
| // Copyright (C) 2020 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. |
| // |
| |
| #ifndef UPDATE_ENGINE_PAYLOAD_GENERATOR_MERGE_SEQUENCE_GENERATOR_H_ |
| #define UPDATE_ENGINE_PAYLOAD_GENERATOR_MERGE_SEQUENCE_GENERATOR_H_ |
| |
| #include <map> |
| #include <memory> |
| #include <set> |
| #include <utility> |
| #include <vector> |
| |
| #include "update_engine/payload_generator/annotated_operation.h" |
| #include "update_engine/payload_generator/extent_ranges.h" |
| #include "update_engine/payload_generator/extent_utils.h" |
| #include "update_engine/update_metadata.pb.h" |
| |
| namespace chromeos_update_engine { |
| // Constructs CowMergeOperation from src & dst extents |
| CowMergeOperation CreateCowMergeOperation(const Extent& src_extent, |
| const Extent& dst_extent, |
| CowMergeOperation::Type op_type, |
| uint32_t src_offset = 0); |
| |
| // Comparator for CowMergeOperation. |
| bool operator<(const CowMergeOperation& op1, const CowMergeOperation& op2); |
| bool operator==(const CowMergeOperation& op1, const CowMergeOperation& op2); |
| |
| std::ostream& operator<<(std::ostream& os, |
| const CowMergeOperation& merge_operation); |
| |
| // This class takes a list of CowMergeOperations; and sorts them so that no |
| // read after write will happen by following the sequence. When there is a |
| // cycle, we will omit some operations in the list. Therefore, the result |
| // sequence may not contain all blocks in the input list. |
| class MergeSequenceGenerator { |
| public: |
| // Creates an object from a list of OTA InstallOperations. Returns nullptr on |
| // failure. |
| static std::unique_ptr<MergeSequenceGenerator> Create( |
| const std::vector<AnnotatedOperation>& aops); |
| // Checks that no read after write happens in the given sequence. |
| static bool ValidateSequence(const std::vector<CowMergeOperation>& sequence); |
| |
| // Generates a merge sequence from |operations_|, puts the result in |
| // |sequence|. Returns false on failure. |
| bool Generate(std::vector<CowMergeOperation>* sequence) const; |
| |
| private: |
| friend class MergeSequenceGeneratorTest; |
| explicit MergeSequenceGenerator(std::vector<CowMergeOperation> transfers) |
| : operations_(std::move(transfers)) {} |
| |
| // For a given merge operation, finds all the operations that should merge |
| // after myself. Put the result in |merge_after|. |
| bool FindDependency(std::map<CowMergeOperation, std::set<CowMergeOperation>>* |
| merge_after) const; |
| // The list of CowMergeOperations to sort. |
| const std::vector<CowMergeOperation> operations_; |
| }; |
| |
| void SplitSelfOverlapping(const Extent& src_extent, |
| const Extent& dst_extent, |
| std::vector<CowMergeOperation>* sequence); |
| |
| } // namespace chromeos_update_engine |
| #endif |