1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
|
// 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.
#include "bsdiff/brotli_decompressor.h"
#include "bsdiff/logging.h"
namespace bsdiff {
BrotliDecompressor::~BrotliDecompressor() {
if (brotli_decoder_state_)
BrotliDecoderDestroyInstance(brotli_decoder_state_);
}
bool BrotliDecompressor::SetInputData(const uint8_t* input_data, size_t size) {
brotli_decoder_state_ =
BrotliDecoderCreateInstance(nullptr, nullptr, nullptr);
if (brotli_decoder_state_ == nullptr) {
LOG(ERROR) << "Failed to initialize brotli decoder.";
return false;
}
next_in_ = input_data;
available_in_ = size;
return true;
}
bool BrotliDecompressor::Read(uint8_t* output_data, size_t bytes_to_output) {
if (!brotli_decoder_state_) {
LOG(ERROR) << "BrotliDecompressor not initialized";
return false;
}
auto next_out = output_data;
size_t available_out = bytes_to_output;
while (available_out > 0) {
// The brotli decoder will update |available_in_|, |available_in_|,
// |next_out| and |available_out|.
BrotliDecoderResult result = BrotliDecoderDecompressStream(
brotli_decoder_state_, &available_in_, &next_in_, &available_out,
&next_out, nullptr);
if (result == BROTLI_DECODER_RESULT_ERROR) {
LOG(ERROR) << "Decompression failed with "
<< BrotliDecoderErrorString(
BrotliDecoderGetErrorCode(brotli_decoder_state_));
return false;
} else if (result == BROTLI_DECODER_RESULT_NEEDS_MORE_INPUT) {
LOG(ERROR) << "Decompressor reached EOF while reading from input stream.";
return false;
} else if (result == BROTLI_DECODER_RESULT_SUCCESS) {
// This means that decoding is finished, no more input might be consumed
// and no more output will be produced. In the normal case, when there is
// more data available than what was requested in this Read() call it
// returns BROTLI_DECODER_RESULT_NEEDS_MORE_OUTPUT.
if (available_out > 0) {
LOG(ERROR) << "Expected to read " << available_out
<< " more bytes but reached the end of compressed brotli "
"stream";
return false;
}
return true;
}
}
return true;
}
bool BrotliDecompressor::Close() {
if (!brotli_decoder_state_) {
LOG(ERROR) << "BrotliDecompressor not initialized";
return false;
}
// In some cases, the brotli compressed stream could be empty. As a result,
// the function BrotliDecoderIsFinished() will return false because we never
// start the decompression. When that happens, we just destroy the decoder
// and return true.
if (BrotliDecoderIsUsed(brotli_decoder_state_) &&
!BrotliDecoderIsFinished(brotli_decoder_state_)) {
LOG(ERROR) << "Unfinished brotli decoder.";
return false;
}
BrotliDecoderDestroyInstance(brotli_decoder_state_);
brotli_decoder_state_ = nullptr;
return true;
}
} // namespace bsdiff
|
