1 // Copyright (c) 2012 The Chromium 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.
5 #include "net/disk_cache/mapped_file.h"
9 #include "base/files/file_path.h"
10 #include "base/logging.h"
12 namespace disk_cache {
14 void* MappedFile::Init(const base::FilePath& name, size_t size) {
16 if (init_ || !File::Init(name))
22 buffer_ = malloc(size);
23 snapshot_ = malloc(size);
24 if (buffer_ && snapshot_ && Read(buffer_, size, 0)) {
25 memcpy(snapshot_, buffer_, size);
29 buffer_ = snapshot_ = 0;
37 void MappedFile::Flush() {
40 const char* buffer_ptr = static_cast<const char*>(buffer_);
41 char* snapshot_ptr = static_cast<char*>(snapshot_);
42 const size_t block_size = 4096;
43 for (size_t offset = 0; offset < view_size_; offset += block_size) {
44 size_t size = std::min(view_size_ - offset, block_size);
45 if (memcmp(snapshot_ptr + offset, buffer_ptr + offset, size)) {
46 memcpy(snapshot_ptr + offset, buffer_ptr + offset, size);
47 Write(snapshot_ptr + offset, size, offset);
52 MappedFile::~MappedFile() {
56 if (buffer_ && snapshot_) {
63 } // namespace disk_cache