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/*
* Copyright (C) 2009 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef BASE_UNIX_FILE_FD_FILE_H_
#define BASE_UNIX_FILE_FD_FILE_H_
#include <fcntl.h>
#include <string>
#include "base/unix_file/random_access_file.h"
#include "base/macros.h"
namespace unix_file {
// A RandomAccessFile implementation backed by a file descriptor.
//
// Not thread safe.
class FdFile : public RandomAccessFile {
public:
FdFile();
// Creates an FdFile using the given file descriptor. Takes ownership of the
// file descriptor. (Use DisableAutoClose to retain ownership.)
explicit FdFile(int fd);
explicit FdFile(int fd, const std::string& path);
// Destroys an FdFile, closing the file descriptor if Close hasn't already
// been called. (If you care about the return value of Close, call it
// yourself; this is meant to handle failure cases and read-only accesses.
// Note though that calling Close and checking its return value is still no
// guarantee that data actually made it to stable storage.)
virtual ~FdFile();
// Opens file 'file_path' using 'flags' and 'mode'.
bool Open(const std::string& file_path, int flags);
bool Open(const std::string& file_path, int flags, mode_t mode);
// RandomAccessFile API.
virtual int Close();
virtual int64_t Read(char* buf, int64_t byte_count, int64_t offset) const;
virtual int SetLength(int64_t new_length);
virtual int64_t GetLength() const;
virtual int64_t Write(const char* buf, int64_t byte_count, int64_t offset);
virtual int Flush();
// Bonus API.
int Fd() const;
bool IsOpened() const;
std::string GetPath() const;
void DisableAutoClose();
bool ReadFully(void* buffer, int64_t byte_count);
bool WriteFully(const void* buffer, int64_t byte_count);
private:
int fd_;
std::string file_path_;
bool auto_close_;
DISALLOW_COPY_AND_ASSIGN(FdFile);
};
} // namespace unix_file
#endif // BASE_UNIX_FILE_FD_FILE_H_
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