| // Copyright 2017 The Chromium OS Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef _BSDIFF_BZ2_COMPRESSOR_H_ |
| #define _BSDIFF_BZ2_COMPRESSOR_H_ |
| |
| #include <bzlib.h> |
| #include <stdint.h> |
| |
| #include <vector> |
| |
| namespace bsdiff { |
| |
| // An in-memory class to wrap the low-level bzip2 compress functions. This class |
| // allows to stream uncompressed data to it and then retrieve all the compressed |
| // data at the end of the compression step. For that, all the compressed data |
| // is stored in memory. |
| |
| class BZ2Compressor { |
| public: |
| BZ2Compressor(); |
| ~BZ2Compressor(); |
| |
| // Compress and write the data at |buf| of size |size|. |
| bool Write(const uint8_t* buf, size_t size); |
| |
| // Finish the compression step. |
| bool Finish(); |
| |
| // Return the compressed data. This method must be only called after Finish(). |
| const std::vector<uint8_t>& GetCompressedData(); |
| |
| private: |
| // The low-level bzip2 stream. |
| bz_stream bz_strm_; |
| |
| // Whether the bz_strm_ is initialized. |
| bool bz_strm_initialized_{false}; |
| |
| // A list of chunks of compressed data. The final compressed representation is |
| // the concatenation of all the compressed data. |
| std::vector<std::vector<uint8_t>> comp_chunks_; |
| |
| // A concatenated version of the |comp_chunks_|, used to store the compressed |
| // memory after Finish() is called. |
| std::vector<uint8_t> comp_data_; |
| |
| // A temporary compression buffer for multiple calls to Write(). |
| std::vector<uint8_t> comp_buffer_; |
| }; |
| |
| } // namespace bsdiff |
| |
| #endif // _BSDIFF_BZ2_COMPRESSOR_H_ |