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// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// See net/disk_cache/disk_cache.h for the public interface of the cache.
#ifndef NET_DISK_CACHE_MAPPED_FILE_H_
#define NET_DISK_CACHE_MAPPED_FILE_H_
#include <string>
#include "base/ref_counted.h"
#include "net/disk_cache/disk_format.h"
#include "net/disk_cache/file.h"
#include "net/disk_cache/file_block.h"
namespace disk_cache {
// This class implements a memory mapped file used to access block-files. The
// idea is that the header and bitmap will be memory mapped all the time, and
// the actual data for the blocks will be access asynchronously (most of the
// time).
class MappedFile : public File {
public:
MappedFile() : File(true), init_(false) {}
// Performs object initialization. name is the file to use, and size is the
// ammount of data to memory map from th efile. If size is 0, the whole file
// will be mapped in memory.
void* Init(const std::wstring name, size_t size);
void* buffer() const {
return buffer_;
}
// Loads or stores a given block from the backing file (synchronously).
bool Load(const FileBlock* block);
bool Store(const FileBlock* block);
protected:
virtual ~MappedFile();
private:
bool init_;
#if defined(OS_WIN)
HANDLE section_;
#endif
void* buffer_; // Address of the memory mapped buffer.
size_t view_size_; // Size of the memory pointed by buffer_.
DISALLOW_COPY_AND_ASSIGN(MappedFile);
};
} // namespace disk_cache
#endif // NET_DISK_CACHE_MAPPED_FILE_H_