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_CONSUMER_XZ_EXTENT_WRITER_H_ 18 #define UPDATE_ENGINE_PAYLOAD_CONSUMER_XZ_EXTENT_WRITER_H_ 19 20 #include <xz.h> 21 22 #include <memory> 23 #include <utility> 24 25 #include <brillo/secure_blob.h> 26 27 #include "update_engine/payload_consumer/extent_writer.h" 28 29 // XzExtentWriter is a concrete ExtentWriter subclass that xz-decompresses 30 // what it's given in Write using xz-embedded. Note that xz-embedded only 31 // supports files with either no CRC or CRC-32. It passes the decompressed data 32 // to an underlying ExtentWriter. 33 34 namespace chromeos_update_engine { 35 36 class XzExtentWriter : public ExtentWriter { 37 public: XzExtentWriter(std::unique_ptr<ExtentWriter> underlying_writer)38 explicit XzExtentWriter(std::unique_ptr<ExtentWriter> underlying_writer) 39 : underlying_writer_(std::move(underlying_writer)) {} 40 ~XzExtentWriter() override; 41 42 bool Init(FileDescriptorPtr fd, 43 const google::protobuf::RepeatedPtrField<Extent>& extents, 44 uint32_t block_size) override; 45 bool Write(const void* bytes, size_t count) override; 46 47 private: 48 // The underlying ExtentWriter. 49 std::unique_ptr<ExtentWriter> underlying_writer_; 50 // The opaque xz decompressor struct. 51 xz_dec* stream_{nullptr}; 52 brillo::Blob input_buffer_; 53 54 DISALLOW_COPY_AND_ASSIGN(XzExtentWriter); 55 }; 56 57 } // namespace chromeos_update_engine 58 59 #endif // UPDATE_ENGINE_PAYLOAD_CONSUMER_XZ_EXTENT_WRITER_H_ 60