Move BufferedSocketWriter from remoting/protocol to remoting/base

remoting/protocol/buffered_socket_writer.h

-// 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 REMOTING_PROTOCOL_BUFFERED_SOCKET_WRITER_H_
-#define REMOTING_PROTOCOL_BUFFERED_SOCKET_WRITER_H_
-
-#include <list>
-
-#include "base/callback.h"
-#include "base/synchronization/lock.h"
-#include "base/threading/non_thread_safe.h"
-#include "net/base/io_buffer.h"
-#include "net/socket/socket.h"
-
-namespace net {
-class Socket;
-}  // namespace net
-
-namespace remoting {
-namespace protocol {
-
-// BufferedSocketWriter and BufferedDatagramWriter implement write data queue
-// for stream and datagram sockets. BufferedSocketWriterBase is a base class
-// that implements base functionality common for streams and datagrams.
-// These classes are particularly useful when data comes from a thread
-// that doesn't own the socket, as Write() can be called from any thread.
-// Whenever new data is written it is just put in the queue, and then written
-// on the thread that owns the socket. GetBufferChunks() and GetBufferSize()
-// can be used to throttle writes.
-
-class BufferedSocketWriterBase : public base::NonThreadSafe {
- public:
-  typedef base::Callback<void(int)> WriteFailedCallback;
-
-  BufferedSocketWriterBase();
-  virtual ~BufferedSocketWriterBase();
-
-  // Initializes the writer. Must be called on the thread that will be used
-  // to access the socket in the future. |callback| will be called after each
-  // failed write. Caller retains ownership of |socket|.
-  // TODO(sergeyu): Change it so that it take ownership of |socket|.
-  void Init(net::Socket* socket, const WriteFailedCallback& callback);
-
-  // Puts a new data chunk in the buffer. Returns false and doesn't enqueue
-  // the data if called before Init(). Can be called on any thread.
-  bool Write(scoped_refptr<net::IOBufferWithSize> buffer,
-             const base::Closure& done_task);
-
-  // Returns current size of the buffer. Can be called on any thread.
-  int GetBufferSize();
-
-  // Returns number of chunks that are currently in the buffer waiting
-  // to be written. Can be called on any thread.
-  int GetBufferChunks();
-
-  // Stops writing and drops current buffers. Must be called on the
-  // network thread.
-  void Close();
-
- protected:
-  struct PendingPacket;
-  typedef std::list<PendingPacket*> DataQueue;
-
-  DataQueue queue_;
-  int buffer_size_;
-
-  // Removes element from the front of the queue and returns |done_task| for
-  // that element. Called from AdvanceBufferPosition() implementation, which
-  // then returns result of this function to its caller.
-  base::Closure PopQueue();
-
-  // Following three methods must be implemented in child classes.
-
-  // Returns next packet that needs to be written to the socket. Implementation
-  // must set |*buffer| to nullptr if there is nothing left in the queue.
-  virtual void GetNextPacket(net::IOBuffer** buffer, int* size) = 0;
-
-  // Returns closure that must be executed or null closure if the last write
-  // didn't complete any messages.
-  virtual base::Closure AdvanceBufferPosition(int written) = 0;
-
-  // This method is called whenever there is an error writing to the socket.
-  virtual void OnError(int result) = 0;
-
- private:
-  void DoWrite();
-  void HandleWriteResult(int result, bool* write_again);
-  void OnWritten(int result);
-
-  // This method is called when an error is encountered.
-  void HandleError(int result);
-
-  net::Socket* socket_;
-  WriteFailedCallback write_failed_callback_;
-
-  bool write_pending_;
-
-  bool closed_;
-
-  bool* destroyed_flag_;
-};
-
-class BufferedSocketWriter : public BufferedSocketWriterBase {
- public:
-  BufferedSocketWriter();
-  ~BufferedSocketWriter() override;
-
- protected:
-  void GetNextPacket(net::IOBuffer** buffer, int* size) override;
-  base::Closure AdvanceBufferPosition(int written) override;
-  void OnError(int result) override;
-
- private:
-  scoped_refptr<net::DrainableIOBuffer> current_buf_;
-};
-
-class BufferedDatagramWriter : public BufferedSocketWriterBase {
- public:
-  BufferedDatagramWriter();
-  ~BufferedDatagramWriter() override;
-
- protected:
-  void GetNextPacket(net::IOBuffer** buffer, int* size) override;
-  base::Closure AdvanceBufferPosition(int written) override;
-  void OnError(int result) override;
-};
-
-}  // namespace protocol
-}  // namespace remoting
-
-#endif  // REMOTING_PROTOCOL_BUFFERED_SOCKET_WRITER_H_