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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_BLOB_LOCAL_FILE_STREAM_READER_H_
#define WEBKIT_BLOB_LOCAL_FILE_STREAM_READER_H_
#include "base/basictypes.h"
#include "base/compiler_specific.h"
#include "base/file_path.h"
#include "base/memory/weak_ptr.h"
#include "base/platform_file.h"
#include "base/time.h"
#include "webkit/blob/file_stream_reader.h"
#include "webkit/storage/webkit_storage_export.h"
namespace base {
class TaskRunner;
}
namespace net {
class FileStream;
}
namespace webkit_blob {
// A thin wrapper of net::FileStream with range support for sliced file
// handling.
class WEBKIT_STORAGE_EXPORT LocalFileStreamReader : public FileStreamReader {
public:
// Creates a new FileReader for a local file |file_path|.
// |initial_offset| specifies the offset in the file where the first read
// should start. If the given offset is out of the file range any
// read operation may error out with net::ERR_REQUEST_RANGE_NOT_SATISFIABLE.
//
// |expected_modification_time| specifies the expected last modification
// If the value is non-null, the reader will check the underlying file's
// actual modification time to see if the file has been modified, and if
// it does any succeeding read operations should fail with
// ERR_UPLOAD_FILE_CHANGED error.
LocalFileStreamReader(base::TaskRunner* task_runner,
const FilePath& file_path,
int64 initial_offset,
const base::Time& expected_modification_time);
virtual ~LocalFileStreamReader();
// FileStreamReader overrides.
virtual int Read(net::IOBuffer* buf, int buf_len,
const net::CompletionCallback& callback) OVERRIDE;
virtual int GetLength(
const net::Int64CompletionCallback& callback) OVERRIDE;
private:
int Open(const net::CompletionCallback& callback);
// Callbacks that are chained from Open for Read.
void DidVerifyForOpen(const net::CompletionCallback& callback,
int64 get_length_result);
void DidOpenFileStream(const net::CompletionCallback& callback,
int result);
void DidSeekFileStream(const net::CompletionCallback& callback,
int64 seek_result);
void DidOpenForRead(net::IOBuffer* buf,
int buf_len,
const net::CompletionCallback& callback,
int open_result);
void DidGetFileInfoForGetLength(const net::Int64CompletionCallback& callback,
base::PlatformFileError error,
const base::PlatformFileInfo& file_info);
scoped_refptr<base::TaskRunner> task_runner_;
scoped_ptr<net::FileStream> stream_impl_;
const FilePath file_path_;
const int64 initial_offset_;
const base::Time expected_modification_time_;
bool has_pending_open_;
base::WeakPtrFactory<LocalFileStreamReader> weak_factory_;
};
} // namespace webkit_blob
#endif // WEBKIT_BLOB_LOCAL_FILE_STREAM_READER_H_
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