net/socket/socket.h

   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
  11 namespace net {
  12
  13 class IOBuffer;
  14
  15 // Represents a read/write socket.
  16 class 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 true on success, or false on failure.
  52   virtual bool 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 true on success, or false on failure.
  57   virtual bool SetSendBufferSize(int32 size) = 0;
  58 };
  59
  60 }  // namespace net
  61
  62 #endif  // NET_SOCKET_SOCKET_H_