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// Copyright (c) 2012 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.
#ifndef WEBKIT_FILEAPI_LOCAL_FILE_WRITER_H_
#define WEBKIT_FILEAPI_LOCAL_FILE_WRITER_H_
#pragma once
#include <utility>
#include "base/compiler_specific.h"
#include "base/callback.h"
#include "base/file_path.h"
#include "base/platform_file.h"
#include "base/memory/scoped_ptr.h"
#include "base/memory/weak_ptr.h"
#include "webkit/fileapi/file_writer.h"
namespace net {
class FileStream;
}
namespace fileapi {
// This class is a thin wrapper around net::FileStream for writing local files.
class LocalFileWriter : public FileWriter {
public:
// Create a writer for the existing file in the path |file_path| starting from
// |initial_offset|.
LocalFileWriter(const FilePath& file_path, int64 initial_offset);
virtual ~LocalFileWriter();
// FileWriter overrides.
virtual int Write(net::IOBuffer* buf, int buf_len,
const net::CompletionCallback& callback) OVERRIDE;
virtual int Cancel(const net::CompletionCallback& callback) OVERRIDE;
private:
// Opens |file_path_| and if it succeeds, proceeds to InitiateSeek().
// If failed, the error code is returned by calling |error_callback|.
int InitiateOpen(const net::CompletionCallback& error_callback,
const base::Closure& main_operation);
void DidOpen(const net::CompletionCallback& error_callback,
const base::Closure& main_operation,
int result);
// Seeks to |initial_offset_| and proceeds to |main_operation| if it succeeds.
// If failed, the error code is returned by calling |error_callback|.
void InitiateSeek(const net::CompletionCallback& error_callback,
const base::Closure& main_operation);
void DidSeek(const net::CompletionCallback& error_callback,
const base::Closure& main_operation,
int64 result);
// Passed as the |main_operation| of InitiateOpen() function.
void ReadyToWrite(net::IOBuffer* buf, int buf_len,
const net::CompletionCallback& callback);
// Writes asynchronously to the file.
int InitiateWrite(net::IOBuffer* buf, int buf_len,
const net::CompletionCallback& callback);
void DidWrite(const net::CompletionCallback& callback, int result);
// Stops the in-flight operation and calls |cancel_callback_| if it has been
// set by Cancel() for the current operation.
bool CancelIfRequested();
// Initialization parameters.
const FilePath file_path_;
const int64 initial_offset_;
// Current states of the operation.
bool has_pending_operation_;
scoped_ptr<net::FileStream> stream_impl_;
net::CompletionCallback cancel_callback_;
base::WeakPtrFactory<LocalFileWriter> weak_factory_;
DISALLOW_COPY_AND_ASSIGN(LocalFileWriter);
};
} // namespace fileapi
#endif // WEBKIT_FILEAPI_LOCAL_FILE_WRITER_H_
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