net/socket/tcp_client_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_TCP_CLIENT_SOCKET_H_
   6 #define NET_SOCKET_TCP_CLIENT_SOCKET_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/compiler_specific.h"
  10 #include "base/memory/scoped_ptr.h"
  11 #include "net/base/address_list.h"
  12 #include "net/base/completion_callback.h"
  13 #include "net/base/net_export.h"
  14 #include "net/log/net_log.h"
  15 #include "net/socket/connection_attempts.h"
  16 #include "net/socket/stream_socket.h"
  17 #include "net/socket/tcp_socket.h"
  18
  19 namespace net {
  20
  21 // A client socket that uses TCP as the transport layer.
  22 class NET_EXPORT TCPClientSocket : public StreamSocket {
  23  public:
  24   // The IP address(es) and port number to connect to.  The TCP socket will try
  25   // each IP address in the list until it succeeds in establishing a
  26   // connection.
  27   TCPClientSocket(const AddressList& addresses,
  28                   net::NetLog* net_log,
  29                   const net::NetLog::Source& source);
  30
  31   // Adopts the given, connected socket and then acts as if Connect() had been
  32   // called. This function is used by TCPServerSocket and for testing.
  33   TCPClientSocket(scoped_ptr<TCPSocket> connected_socket,
  34                   const IPEndPoint& peer_address);
  35
  36   ~TCPClientSocket() override;
  37
  38   // Binds the socket to a local IP address and port.
  39   int Bind(const IPEndPoint& address);
  40
  41   // StreamSocket implementation.
  42   int Connect(const CompletionCallback& callback) override;
  43   void Disconnect() override;
  44   bool IsConnected() const override;
  45   bool IsConnectedAndIdle() const override;
  46   int GetPeerAddress(IPEndPoint* address) const override;
  47   int GetLocalAddress(IPEndPoint* address) const override;
  48   const BoundNetLog& NetLog() const override;
  49   void SetSubresourceSpeculation() override;
  50   void SetOmniboxSpeculation() override;
  51   bool WasEverUsed() const override;
  52   bool UsingTCPFastOpen() const override;
  53   void EnableTCPFastOpenIfSupported() override;
  54   bool WasNpnNegotiated() const override;
  55   NextProto GetNegotiatedProtocol() const override;
  56   bool GetSSLInfo(SSLInfo* ssl_info) override;
  57
  58   // Socket implementation.
  59   // Multiple outstanding requests are not supported.
  60   // Full duplex mode (reading and writing at the same time) is supported.
  61   int Read(IOBuffer* buf,
  62            int buf_len,
  63            const CompletionCallback& callback) override;
  64   int Write(IOBuffer* buf,
  65             int buf_len,
  66             const CompletionCallback& callback) override;
  67   int SetReceiveBufferSize(int32 size) override;
  68   int SetSendBufferSize(int32 size) override;
  69
  70   virtual bool SetKeepAlive(bool enable, int delay);
  71   virtual bool SetNoDelay(bool no_delay);
  72
  73   void GetConnectionAttempts(ConnectionAttempts* out) const override;
  74   void ClearConnectionAttempts() override;
  75   void AddConnectionAttempts(const ConnectionAttempts& attempts) override;
  76
  77  private:
  78   // State machine for connecting the socket.
  79   enum ConnectState {
  80     CONNECT_STATE_CONNECT,
  81     CONNECT_STATE_CONNECT_COMPLETE,
  82     CONNECT_STATE_NONE,
  83   };
  84
  85   // State machine used by Connect().
  86   int DoConnectLoop(int result);
  87   int DoConnect();
  88   int DoConnectComplete(int result);
  89
  90   // Helper used by Disconnect(), which disconnects minus resetting
  91   // current_address_index_ and bind_address_.
  92   void DoDisconnect();
  93
  94   void DidCompleteConnect(int result);
  95   void DidCompleteReadWrite(const CompletionCallback& callback, int result);
  96
  97   int OpenSocket(AddressFamily family);
  98
  99   // Emits histograms for TCP metrics, at the time the socket is
 100   // disconnected.
 101   void EmitTCPMetricsHistogramsOnDisconnect();
 102
 103   scoped_ptr<TCPSocket> socket_;
 104
 105   // Local IP address and port we are bound to. Set to NULL if Bind()
 106   // wasn't called (in that case OS chooses address/port).
 107   scoped_ptr<IPEndPoint> bind_address_;
 108
 109   // The list of addresses we should try in order to establish a connection.
 110   AddressList addresses_;
 111
 112   // Where we are in above list. Set to -1 if uninitialized.
 113   int current_address_index_;
 114
 115   // External callback; called when connect is complete.
 116   CompletionCallback connect_callback_;
 117
 118   // The next state for the Connect() state machine.
 119   ConnectState next_connect_state_;
 120
 121   // This socket was previously disconnected and has not been re-connected.
 122   bool previously_disconnected_;
 123
 124   // Record of connectivity and transmissions, for use in speculative connection
 125   // histograms.
 126   UseHistory use_history_;
 127
 128   // Failed connection attempts made while trying to connect this socket.
 129   ConnectionAttempts connection_attempts_;
 130
 131   DISALLOW_COPY_AND_ASSIGN(TCPClientSocket);
 132 };
 133
 134 }  // namespace net
 135
 136 #endif  // NET_SOCKET_TCP_CLIENT_SOCKET_H_