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_EXTENT_UTILS_H_ 18 #define UPDATE_ENGINE_PAYLOAD_GENERATOR_EXTENT_UTILS_H_ 19 20 #include <string> 21 #include <vector> 22 23 #include "update_engine/payload_consumer/payload_constants.h" 24 #include "update_engine/update_metadata.pb.h" 25 26 // Utility functions for manipulating Extents and lists of blocks. 27 28 namespace chromeos_update_engine { 29 30 // |block| must either be the next block in the last extent or a block 31 // in the next extent. This function will not handle inserting block 32 // into an arbitrary place in the extents. 33 void AppendBlockToExtents(std::vector<Extent>* extents, uint64_t block); 34 35 // Takes a collection (vector or RepeatedPtrField) of Extent and 36 // returns a vector of the blocks referenced, in order. 37 template <typename T> 38 std::vector<uint64_t> ExpandExtents(const T& extents) { 39 std::vector<uint64_t> ret; 40 for (const auto& extent : extents) { 41 if (extent.start_block() == kSparseHole) { 42 ret.resize(ret.size() + extent.num_blocks(), kSparseHole); 43 } else { 44 for (uint64_t block = extent.start_block(); 45 block < (extent.start_block() + extent.num_blocks()); 46 block++) { 47 ret.push_back(block); 48 } 49 } 50 } 51 return ret; 52 } 53 54 // Stores all Extents in 'extents' into 'out'. 55 void StoreExtents(const std::vector<Extent>& extents, 56 google::protobuf::RepeatedPtrField<Extent>* out); 57 58 // Stores all extents in |extents| into |out_vector|. 59 void ExtentsToVector(const google::protobuf::RepeatedPtrField<Extent>& extents, 60 std::vector<Extent>* out_vector); 61 62 // Returns a string representing all extents in |extents|. 63 std::string ExtentsToString(const std::vector<Extent>& extents); 64 65 // Takes a pointer to extents |extents| and extents |extents_to_add|, and 66 // merges them by adding |extents_to_add| to |extents| and normalizing. 67 void ExtendExtents( 68 google::protobuf::RepeatedPtrField<Extent>* extents, 69 const google::protobuf::RepeatedPtrField<Extent>& extents_to_add); 70 71 // Takes a vector of extents and normalizes those extents. Expects the extents 72 // to be sorted by start block. E.g. if |extents| is [(1, 2), (3, 5), (10, 2)] 73 // then |extents| will be changed to [(1, 7), (10, 2)]. 74 void NormalizeExtents(std::vector<Extent>* extents); 75 76 // Return a subsequence of the list of blocks passed. Both the passed list of 77 // blocks |extents| and the return value are expressed as a list of Extent, not 78 // blocks. The returned list skips the first |block_offset| blocks from the 79 // |extents| and cotains |block_count| blocks (or less if |extents| is shorter). 80 std::vector<Extent> ExtentsSublist(const std::vector<Extent>& extents, 81 uint64_t block_offset, 82 uint64_t block_count); 83 84 bool operator==(const Extent& a, const Extent& b); 85 86 } // namespace chromeos_update_engine 87 88 #endif // UPDATE_ENGINE_PAYLOAD_GENERATOR_EXTENT_UTILS_H_ 89