net/socket/stream_socket.h

   1 // Copyright (c) 2012 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_STREAM_SOCKET_H_
   6 #define NET_SOCKET_STREAM_SOCKET_H_
   7
   8 #include "net/log/net_log.h"
   9 #include "net/socket/connection_attempts.h"
  10 #include "net/socket/next_proto.h"
  11 #include "net/socket/socket.h"
  12
  13 namespace net {
  14
  15 class AddressList;
  16 class IPEndPoint;
  17 class SSLInfo;
  18
  19 class NET_EXPORT_PRIVATE StreamSocket : public Socket {
  20  public:
  21   ~StreamSocket() override {}
  22
  23   // Called to establish a connection.  Returns OK if the connection could be
  24   // established synchronously.  Otherwise, ERR_IO_PENDING is returned and the
  25   // given callback will run asynchronously when the connection is established
  26   // or when an error occurs.  The result is some other error code if the
  27   // connection could not be established.
  28   //
  29   // The socket's Read and Write methods may not be called until Connect
  30   // succeeds.
  31   //
  32   // It is valid to call Connect on an already connected socket, in which case
  33   // OK is simply returned.
  34   //
  35   // Connect may also be called again after a call to the Disconnect method.
  36   //
  37   virtual int Connect(const CompletionCallback& callback) = 0;
  38
  39   // Called to disconnect a socket.  Does nothing if the socket is already
  40   // disconnected.  After calling Disconnect it is possible to call Connect
  41   // again to establish a new connection.
  42   //
  43   // If IO (Connect, Read, or Write) is pending when the socket is
  44   // disconnected, the pending IO is cancelled, and the completion callback
  45   // will not be called.
  46   virtual void Disconnect() = 0;
  47
  48   // Called to test if the connection is still alive.  Returns false if a
  49   // connection wasn't established or the connection is dead.
  50   virtual bool IsConnected() const = 0;
  51
  52   // Called to test if the connection is still alive and idle.  Returns false
  53   // if a connection wasn't established, the connection is dead, or some data
  54   // have been received.
  55   virtual bool IsConnectedAndIdle() const = 0;
  56
  57   // Copies the peer address to |address| and returns a network error code.
  58   // ERR_SOCKET_NOT_CONNECTED will be returned if the socket is not connected.
  59   virtual int GetPeerAddress(IPEndPoint* address) const = 0;
  60
  61   // Copies the local address to |address| and returns a network error code.
  62   // ERR_SOCKET_NOT_CONNECTED will be returned if the socket is not bound.
  63   virtual int GetLocalAddress(IPEndPoint* address) const = 0;
  64
  65   // Gets the NetLog for this socket.
  66   virtual const BoundNetLog& NetLog() const = 0;
  67
  68   // Set the annotation to indicate this socket was created for speculative
  69   // reasons.  This call is generally forwarded to a basic TCPClientSocket*,
  70   // where a UseHistory can be updated.
  71   virtual void SetSubresourceSpeculation() = 0;
  72   virtual void SetOmniboxSpeculation() = 0;
  73
  74   // Returns true if the socket ever had any reads or writes.  StreamSockets
  75   // layered on top of transport sockets should return if their own Read() or
  76   // Write() methods had been called, not the underlying transport's.
  77   virtual bool WasEverUsed() const = 0;
  78
  79   // TODO(jri): Clean up -- remove this method.
  80   // Returns true if the underlying transport socket is using TCP FastOpen.
  81   // TCP FastOpen is an experiment with sending data in the TCP SYN packet.
  82   virtual bool UsingTCPFastOpen() const = 0;
  83
  84   // TODO(jri): Clean up -- rename to a more general EnableAutoConnectOnWrite.
  85   // Enables use of TCP FastOpen for the underlying transport socket.
  86   virtual void EnableTCPFastOpenIfSupported() {}
  87
  88   // Returns true if NPN was negotiated during the connection of this socket.
  89   virtual bool WasNpnNegotiated() const = 0;
  90
  91   // Returns the protocol negotiated via NPN for this socket, or
  92   // kProtoUnknown will be returned if NPN is not applicable.
  93   virtual NextProto GetNegotiatedProtocol() const = 0;
  94
  95   // Gets the SSL connection information of the socket.  Returns false if
  96   // SSL was not used by this socket.
  97   virtual bool GetSSLInfo(SSLInfo* ssl_info) = 0;
  98
  99   // Overwrites |out| with the connection attempts made in the process of
 100   // connecting this socket.
 101   virtual void GetConnectionAttempts(ConnectionAttempts* out) const = 0;
 102
 103   // Clears the socket's list of connection attempts.
 104   virtual void ClearConnectionAttempts() = 0;
 105
 106   // Adds |attempts| to the socket's list of connection attempts.
 107   virtual void AddConnectionAttempts(const ConnectionAttempts& attempts) = 0;
 108
 109  protected:
 110   // The following class is only used to gather statistics about the history of
 111   // a socket.  It is only instantiated and used in basic sockets, such as
 112   // TCPClientSocket* instances.  Other classes that are derived from
 113   // StreamSocket should forward any potential settings to their underlying
 114   // transport sockets.
 115   class UseHistory {
 116    public:
 117     UseHistory();
 118     ~UseHistory();
 119
 120     // Resets the state of UseHistory and emits histograms for the
 121     // current state.
 122     void Reset();
 123
 124     void set_was_ever_connected();
 125     void set_was_used_to_convey_data();
 126
 127     // The next two setters only have any impact if the socket has not yet been
 128     // used to transmit data.  If called later, we assume that the socket was
 129     // reused from the pool, and was NOT constructed to service a speculative
 130     // request.
 131     void set_subresource_speculation();
 132     void set_omnibox_speculation();
 133
 134     bool was_used_to_convey_data() const;
 135
 136    private:
 137     // Summarize the statistics for this socket.
 138     void EmitPreconnectionHistograms() const;
 139     // Indicate if this was ever connected.
 140     bool was_ever_connected_;
 141     // Indicate if this socket was ever used to transmit or receive data.
 142     bool was_used_to_convey_data_;
 143
 144     // Indicate if this socket was first created for speculative use, and
 145     // identify the motivation.
 146     bool omnibox_speculation_;
 147     bool subresource_speculation_;
 148     DISALLOW_COPY_AND_ASSIGN(UseHistory);
 149   };
 150 };
 151
 152 }  // namespace net
 153
 154 #endif  // NET_SOCKET_STREAM_SOCKET_H_