net/disk_cache/blockfile/mapped_file_win.cc

   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.
   4
   5 #include "net/disk_cache/blockfile/mapped_file.h"
   6
   7 #include "base/files/file_path.h"
   8 #include "base/logging.h"
   9 #include "base/memory/scoped_ptr.h"
  10 #include "net/disk_cache/disk_cache.h"
  11
  12 namespace disk_cache {
  13
  14 void* MappedFile::Init(const base::FilePath& name, size_t size) {
  15   DCHECK(!init_);
  16   if (init_ || !File::Init(name))
  17     return NULL;
  18
  19   buffer_ = NULL;
  20   init_ = true;
  21   section_ = CreateFileMapping(platform_file(), NULL, PAGE_READWRITE, 0,
  22                                static_cast<DWORD>(size), NULL);
  23   if (!section_)
  24     return NULL;
  25
  26   buffer_ = MapViewOfFile(section_, FILE_MAP_READ | FILE_MAP_WRITE, 0, 0, size);
  27   DCHECK(buffer_);
  28   view_size_ = size;
  29
  30   // Make sure we detect hardware failures reading the headers.
  31   size_t temp_len = size ? size : 4096;
  32   scoped_ptr<char[]> temp(new char[temp_len]);
  33   if (!Read(temp.get(), temp_len, 0))
  34     return NULL;
  35
  36   return buffer_;
  37 }
  38
  39 MappedFile::~MappedFile() {
  40   if (!init_)
  41     return;
  42
  43   if (buffer_) {
  44     BOOL ret = UnmapViewOfFile(buffer_);
  45     DCHECK(ret);
  46   }
  47
  48   if (section_)
  49     CloseHandle(section_);
  50 }
  51
  52 void MappedFile::Flush() {
  53 }
  54
  55 }  // namespace disk_cache