xz_chromeos.cc revision 717c324c334cc3bac954101f7a127fe8ef56e4e6 
1//
2// Copyright (C) 2016 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#include "update_engine/payload_generator/xz.h"
18
19#include <base/logging.h>
20#include <lzma.h>
21
22namespace chromeos_update_engine {
23
24void XzCompressInit() {}
25
26bool XzCompress(const brillo::Blob& in, brillo::Blob* out) {
27  out->clear();
28  if (in.empty())
29    return true;
30
31  // Resize the output buffer to get enough memory for writing the compressed
32  // data.
33  out->resize(lzma_stream_buffer_bound(in.size()));
34
35  const uint32_t kLzmaPreset = 6;
36  size_t out_pos = 0;
37  int rc = lzma_easy_buffer_encode(kLzmaPreset,
38                                   LZMA_CHECK_NONE,  // We do not need CRC.
39                                   nullptr,
40                                   in.data(),
41                                   in.size(),
42                                   out->data(),
43                                   &out_pos,
44                                   out->size());
45  if (rc != LZMA_OK) {
46    LOG(ERROR) << "Failed to compress data to LZMA stream with return code: "
47               << rc;
48    return false;
49  }
50  out->resize(out_pos);
51  return true;
52}
53
54}  // namespace chromeos_update_engine
55