Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 1 | // Copyright 2017 The Chromium OS Authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
Alex Deymo | dcd423b | 2017-09-13 20:54:24 +0200 | [diff] [blame] | 5 | #include "bsdiff/bz2_compressor.h" |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 6 | |
| 7 | #include <string.h> |
| 8 | |
Alex Deymo | dcd423b | 2017-09-13 20:54:24 +0200 | [diff] [blame] | 9 | #include "bsdiff/logging.h" |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 10 | |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 11 | namespace { |
| 12 | |
| 13 | // The BZ2 compression level used. Smaller compression levels are nowadays |
| 14 | // pointless. |
| 15 | const int kCompressionLevel = 9; |
| 16 | |
| 17 | } // namespace |
| 18 | |
| 19 | namespace bsdiff { |
| 20 | |
Tianjie Xu | 1c26e2e | 2017-10-26 17:19:41 -0700 | [diff] [blame] | 21 | BZ2Compressor::BZ2Compressor() : comp_buffer_(1024 * 1024) { |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 22 | memset(&bz_strm_, 0, sizeof(bz_strm_)); |
| 23 | int bz_err = BZ2_bzCompressInit(&bz_strm_, kCompressionLevel, |
| 24 | 0 /* verbosity */, 0 /* workFactor */); |
| 25 | if (bz_err != BZ_OK) { |
Tianjie Xu | 18480eb | 2017-11-29 16:21:43 -0800 | [diff] [blame] | 26 | LOG(ERROR) << "Initializing bz_strm, bz_error=" << bz_err; |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 27 | } else { |
| 28 | bz_strm_initialized_ = true; |
| 29 | } |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 30 | } |
| 31 | |
| 32 | BZ2Compressor::~BZ2Compressor() { |
| 33 | if (!bz_strm_initialized_) |
| 34 | return; |
| 35 | int bz_err = BZ2_bzCompressEnd(&bz_strm_); |
| 36 | if (bz_err != BZ_OK) { |
Tianjie Xu | 18480eb | 2017-11-29 16:21:43 -0800 | [diff] [blame] | 37 | LOG(ERROR) << "Deleting the compressor stream, bz_error=" << bz_err; |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 38 | } |
| 39 | } |
| 40 | |
| 41 | bool BZ2Compressor::Write(const uint8_t* buf, size_t size) { |
| 42 | if (!bz_strm_initialized_) |
| 43 | return false; |
| 44 | |
| 45 | // The bz_stream struct defines the next_in as a non-const data pointer, |
| 46 | // although the documentation says it won't modify it. |
| 47 | bz_strm_.next_in = reinterpret_cast<char*>(const_cast<uint8_t*>(buf)); |
| 48 | bz_strm_.avail_in = size; |
| 49 | |
| 50 | while (bz_strm_.avail_in) { |
Tianjie Xu | 1c26e2e | 2017-10-26 17:19:41 -0700 | [diff] [blame] | 51 | bz_strm_.next_out = reinterpret_cast<char*>(comp_buffer_.buffer_data()); |
| 52 | bz_strm_.avail_out = comp_buffer_.buffer_size(); |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 53 | int bz_err = BZ2_bzCompress(&bz_strm_, BZ_RUN); |
| 54 | if (bz_err != BZ_RUN_OK) { |
Tianjie Xu | 18480eb | 2017-11-29 16:21:43 -0800 | [diff] [blame] | 55 | LOG(ERROR) << "Compressing data, bz_error=" << bz_err; |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 56 | return false; |
| 57 | } |
| 58 | |
Tianjie Xu | 1c26e2e | 2017-10-26 17:19:41 -0700 | [diff] [blame] | 59 | uint64_t output_bytes = comp_buffer_.buffer_size() - bz_strm_.avail_out; |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 60 | if (output_bytes) { |
Tianjie Xu | 1c26e2e | 2017-10-26 17:19:41 -0700 | [diff] [blame] | 61 | comp_buffer_.AddDataToChunks(output_bytes); |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 62 | } |
| 63 | } |
| 64 | return true; |
| 65 | } |
| 66 | |
| 67 | bool BZ2Compressor::Finish() { |
| 68 | if (!bz_strm_initialized_) |
| 69 | return false; |
| 70 | bz_strm_.next_in = nullptr; |
| 71 | bz_strm_.avail_in = 0; |
| 72 | |
| 73 | int bz_err = BZ_FINISH_OK; |
| 74 | while (bz_err == BZ_FINISH_OK) { |
Tianjie Xu | 1c26e2e | 2017-10-26 17:19:41 -0700 | [diff] [blame] | 75 | bz_strm_.next_out = reinterpret_cast<char*>(comp_buffer_.buffer_data()); |
| 76 | bz_strm_.avail_out = comp_buffer_.buffer_size(); |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 77 | bz_err = BZ2_bzCompress(&bz_strm_, BZ_FINISH); |
| 78 | |
Tianjie Xu | 1c26e2e | 2017-10-26 17:19:41 -0700 | [diff] [blame] | 79 | uint64_t output_bytes = comp_buffer_.buffer_size() - bz_strm_.avail_out; |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 80 | if (output_bytes) { |
Tianjie Xu | 1c26e2e | 2017-10-26 17:19:41 -0700 | [diff] [blame] | 81 | comp_buffer_.AddDataToChunks(output_bytes); |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 82 | } |
| 83 | } |
| 84 | if (bz_err != BZ_STREAM_END) { |
Tianjie Xu | 18480eb | 2017-11-29 16:21:43 -0800 | [diff] [blame] | 85 | LOG(ERROR) << "Finishing compressing data, bz_error=" << bz_err; |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 86 | return false; |
| 87 | } |
| 88 | bz_err = BZ2_bzCompressEnd(&bz_strm_); |
| 89 | bz_strm_initialized_ = false; |
| 90 | if (bz_err != BZ_OK) { |
Tianjie Xu | 18480eb | 2017-11-29 16:21:43 -0800 | [diff] [blame] | 91 | LOG(ERROR) << "Deleting the compressor stream, bz_error=" << bz_err; |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 92 | return false; |
| 93 | } |
| 94 | return true; |
| 95 | } |
| 96 | |
| 97 | const std::vector<uint8_t>& BZ2Compressor::GetCompressedData() { |
Tianjie Xu | 1c26e2e | 2017-10-26 17:19:41 -0700 | [diff] [blame] | 98 | return comp_buffer_.GetCompressedData(); |
Alex Deymo | a28e019 | 2017-09-08 14:21:05 +0200 | [diff] [blame] | 99 | } |
| 100 | |
| 101 | } // namespace bsdiff |