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