1 // 2 // Copyright (C) 2009 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_CONSUMER_EXTENT_WRITER_H_ 18 #define UPDATE_ENGINE_PAYLOAD_CONSUMER_EXTENT_WRITER_H_ 19 20 #include <memory> 21 #include <utility> 22 23 #include <base/logging.h> 24 #include <brillo/secure_blob.h> 25 26 #include "update_engine/common/utils.h" 27 #include "update_engine/payload_consumer/file_descriptor.h" 28 #include "update_engine/update_metadata.pb.h" 29 30 // ExtentWriter is an abstract class which synchronously writes to a given 31 // file descriptor at the extents given. 32 33 namespace chromeos_update_engine { 34 35 class ExtentWriter { 36 public: 37 ExtentWriter() = default; 38 virtual ~ExtentWriter() = default; 39 40 // Returns true on success. 41 virtual bool Init(const google::protobuf::RepeatedPtrField<Extent>& extents, 42 uint32_t block_size) = 0; 43 44 // Returns true on success. 45 virtual bool Write(const void* bytes, size_t count) = 0; 46 }; 47 48 // DirectExtentWriter is probably the simplest ExtentWriter implementation. 49 // It writes the data directly into the extents. 50 51 class DirectExtentWriter : public ExtentWriter { 52 public: DirectExtentWriter(FileDescriptorPtr fd)53 explicit DirectExtentWriter(FileDescriptorPtr fd) : fd_(fd) {} 54 ~DirectExtentWriter() override = default; 55 Init(const google::protobuf::RepeatedPtrField<Extent> & extents,uint32_t block_size)56 bool Init(const google::protobuf::RepeatedPtrField<Extent>& extents, 57 uint32_t block_size) override { 58 block_size_ = block_size; 59 extents_ = extents; 60 cur_extent_ = extents_.begin(); 61 return true; 62 } 63 bool Write(const void* bytes, size_t count) override; 64 65 private: 66 FileDescriptorPtr fd_{nullptr}; 67 68 size_t block_size_{0}; 69 // Bytes written into |cur_extent_| thus far. 70 uint64_t extent_bytes_written_{0}; 71 google::protobuf::RepeatedPtrField<Extent> extents_; 72 // The next call to write should correspond to |cur_extents_|. 73 google::protobuf::RepeatedPtrField<Extent>::iterator cur_extent_; 74 }; 75 76 } // namespace chromeos_update_engine 77 78 #endif // UPDATE_ENGINE_PAYLOAD_CONSUMER_EXTENT_WRITER_H_ 79