1// Copyright (c) 2011 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef NET_SOCKET_SOCKET_H_
6#define NET_SOCKET_SOCKET_H_
7
8#include "net/base/completion_callback.h"
9#include "net/base/net_export.h"
10
11namespace net {
12
13class IOBuffer;
14
15// Represents a read/write socket.
16class NET_EXPORT Socket {
17 public:
18  virtual ~Socket() {}
19
20  // Reads data, up to |buf_len| bytes, from the socket.  The number of bytes
21  // read is returned, or an error is returned upon failure.
22  // ERR_SOCKET_NOT_CONNECTED should be returned if the socket is not currently
23  // connected.  Zero is returned once to indicate end-of-file; the return value
24  // of subsequent calls is undefined, and may be OS dependent.  ERR_IO_PENDING
25  // is returned if the operation could not be completed synchronously, in which
26  // case the result will be passed to the callback when available. If the
27  // operation is not completed immediately, the socket acquires a reference to
28  // the provided buffer until the callback is invoked or the socket is
29  // closed.  If the socket is Disconnected before the read completes, the
30  // callback will not be invoked.
31  virtual int Read(IOBuffer* buf, int buf_len,
32                   const CompletionCallback& callback) = 0;
33
34  // Writes data, up to |buf_len| bytes, to the socket.  Note: data may be
35  // written partially.  The number of bytes written is returned, or an error
36  // is returned upon failure.  ERR_SOCKET_NOT_CONNECTED should be returned if
37  // the socket is not currently connected.  The return value when the
38  // connection is closed is undefined, and may be OS dependent.  ERR_IO_PENDING
39  // is returned if the operation could not be completed synchronously, in which
40  // case the result will be passed to the callback when available.  If the
41  // operation is not completed immediately, the socket acquires a reference to
42  // the provided buffer until the callback is invoked or the socket is
43  // closed.  Implementations of this method should not modify the contents
44  // of the actual buffer that is written to the socket.  If the socket is
45  // Disconnected before the write completes, the callback will not be invoked.
46  virtual int Write(IOBuffer* buf, int buf_len,
47                    const CompletionCallback& callback) = 0;
48
49  // Set the receive buffer size (in bytes) for the socket.
50  // Note: changing this value can affect the TCP window size on some platforms.
51  // Returns a net error code.
52  virtual int SetReceiveBufferSize(int32 size) = 0;
53
54  // Set the send buffer size (in bytes) for the socket.
55  // Note: changing this value can affect the TCP window size on some platforms.
56  // Returns a net error code.
57  virtual int SetSendBufferSize(int32 size) = 0;
58};
59
60}  // namespace net
61
62#endif  // NET_SOCKET_SOCKET_H_
63