vector_output_stream.cc revision 49a0f158ed11974fa2cc12014c9f55a31dabd8df 
1/*
2 * Copyright (C) 2013 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 "vector_output_stream.h"
18
19#include <string.h>
20
21#include "base/logging.h"
22
23namespace art {
24
25VectorOutputStream::VectorOutputStream(const std::string& location, std::vector<uint8_t>& vector)
26  : OutputStream(location), offset_(vector.size()), vector_(vector) {}
27
28bool VectorOutputStream::WriteFully(const void* buffer, int64_t byte_count) {
29  off_t new_offset = offset_ + byte_count;
30  EnsureCapacity(new_offset);
31  memcpy(&vector_[offset_], buffer, byte_count);
32  offset_ = new_offset;
33  return true;
34}
35
36off_t VectorOutputStream::Seek(off_t offset, Whence whence) {
37  CHECK(whence == kSeekSet || whence == kSeekCurrent || whence == kSeekEnd) << whence;
38  off_t new_offset = 0;
39  switch (whence) {
40    case kSeekSet: {
41      new_offset = offset;
42      break;
43    }
44    case kSeekCurrent: {
45      new_offset = offset_ + offset;
46      break;
47    }
48    case kSeekEnd: {
49      new_offset = vector_.size() + offset;
50      break;
51    }
52  }
53  EnsureCapacity(new_offset);
54  offset_ = new_offset;
55  return offset_;
56}
57
58void VectorOutputStream::EnsureCapacity(off_t new_offset) {
59  if (new_offset > static_cast<off_t>(vector_.size())) {
60    vector_.resize(new_offset);
61  }
62}
63
64}  // namespace art
65