POSIX only: Move client socket functionality from TCPClientSocket into TCPSocket.

net/socket/tcp_socket_libevent.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NET_SOCKET_TCP_SOCKET_LIBEVENT_H_
 #define NET_SOCKET_TCP_SOCKET_LIBEVENT_H_
 
 #include "base/basictypes.h"
+#include "base/callback.h"
 #include "base/compiler_specific.h"
+#include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "base/threading/non_thread_safe.h"
 #include "net/base/address_family.h"
 #include "net/base/completion_callback.h"
+#include "net/base/ip_endpoint.h"
 #include "net/base/net_export.h"
 #include "net/base/net_log.h"
+#include "net/socket/socket_descriptor.h"
 
 namespace net {
 
-class IPEndPoint;
-
-// TODO(yzshen): This class is incomplete. TCP client operations (Connect/Read/
-// Write/etc.) will be added. And TCPClientSocket will be changed to be a
-// wrapper around TCPSocket.
-class NET_EXPORT TCPSocketLibevent : public base::NonThreadSafe,
-                                     public base::MessageLoopForIO::Watcher {
+class AddressList;

[akalin, 2013/09/05 22:58:12]

i'm assuming this is all moved from tcp_client_socket_libevent.h

[yzshen1, 2013/09/06 17:19:45]

Mostly yes. A few major changes include:
- ReadWatcher/WriteWatcher are replaced with a more generic Watcher class, which
also supports accept.
- the mutiple-connect-attempts logic is split out and lives in
tcp_client_socket. (Therefore, maybe you want to look at those *Connect*()
methods.)
- the UseHistory logging logic is also split out and lives in tcp_client_socket.
- Close() is made to reset most of the internal state (except logging), so that
it is okay to reuse the object and call Create() again.

On 2013/09/05 22:58:12, akalin wrote:

+class IOBuffer;
+
+class NET_EXPORT TCPSocketLibevent : public base::NonThreadSafe {
  public:
   TCPSocketLibevent(NetLog* net_log, const NetLog::Source& source);
   virtual ~TCPSocketLibevent();
 
   int Create(AddressFamily family);
   // Takes ownership of |socket|.
-  int Adopt(int socket);
-  // Returns a socket file descriptor. The ownership is transferred to the
-  // caller.
-  int Release();
+  int AdoptConnectedSocket(int socket, const IPEndPoint& peer_address);
+
   int Bind(const IPEndPoint& address);
   int GetLocalAddress(IPEndPoint* address) const;
+
   int Listen(int backlog);
   int Accept(scoped_ptr<TCPSocketLibevent>* socket,
              IPEndPoint* address,
              const CompletionCallback& callback);
+
+  int Connect(const IPEndPoint& address, const CompletionCallback& callback);
+  bool IsConnected() const;
+  bool IsConnectedAndIdle() const;
+  int GetPeerAddress(IPEndPoint* address) const;
+
+  // Multiple outstanding requests are not supported.
+  // Full duplex mode (reading and writing at the same time) is supported.
+  int Read(IOBuffer* buf, int buf_len, const CompletionCallback& callback);
+  int Write(IOBuffer* buf, int buf_len, const CompletionCallback& callback);
+
   int SetDefaultOptionsForServer();
+  int SetDefaultOptionsForClient();
   int SetAddressReuse(bool allow);
+  bool SetReceiveBufferSize(int32 size);
+  bool SetSendBufferSize(int32 size);
+  bool SetKeepAlive(bool enable, int delay);
+  bool SetNoDelay(bool no_delay);
+
   void Close();
 
+  bool UsingTCPFastOpen() const;
+  bool IsValid() const { return socket_ != kInvalidSocket; }
+
+  // Marks the start/end of a series of connect attempts for logging purpose.
+  //
+  // TCPClientSocket may attempt to connect to multiple addresses until it
+  // succeeds in establishing a connection. The corresponding log will be
+  // multiple NetLog::TYPE_TCP_CONNECT_ATTEMPT entries nested within a
+  // NetLog::TYPE_TCP_CONNECT. These methods set the start/end of
+  // NetLog::TYPE_TCP_CONNECT.
+  void StartLoggingMultipleConnectAttempts(const AddressList& addresses);
+  void EndLoggingMultipleConnectAttempts(int net_error);
+
   const BoundNetLog& net_log() const { return net_log_; }
 
-  // MessageLoopForIO::Watcher implementation.
-  virtual void OnFileCanReadWithoutBlocking(int fd) OVERRIDE;
-  virtual void OnFileCanWriteWithoutBlocking(int fd) OVERRIDE;
-
  private:
+  // States that a fast open socket attempt can result in.
+  enum FastOpenStatus {
+    FAST_OPEN_STATUS_UNKNOWN,
+
+    // The initial fast open connect attempted returned synchronously,
+    // indicating that we had and sent a cookie along with the initial data.
+    FAST_OPEN_FAST_CONNECT_RETURN,
+
+    // The initial fast open connect attempted returned asynchronously,
+    // indicating that we did not have a cookie for the server.
+    FAST_OPEN_SLOW_CONNECT_RETURN,
+
+    // Some other error occurred on connection, so we couldn't tell if
+    // fast open would have worked.
+    FAST_OPEN_ERROR,
+
+    // An attempt to do a fast open succeeded immediately
+    // (FAST_OPEN_FAST_CONNECT_RETURN) and we later confirmed that the server
+    // had acked the data we sent.
+    FAST_OPEN_SYN_DATA_ACK,
+
+    // An attempt to do a fast open succeeded immediately
+    // (FAST_OPEN_FAST_CONNECT_RETURN) and we later confirmed that the server
+    // had nacked the data we sent.
+    FAST_OPEN_SYN_DATA_NACK,
+
+    // An attempt to do a fast open succeeded immediately
+    // (FAST_OPEN_FAST_CONNECT_RETURN) and our probe to determine if the
+    // socket was using fast open failed.
+    FAST_OPEN_SYN_DATA_FAILED,
+
+    // An attempt to do a fast open failed (FAST_OPEN_SLOW_CONNECT_RETURN)
+    // and we later confirmed that the server had acked initial data.  This
+    // should never happen (we didn't send data, so it shouldn't have
+    // been acked).
+    FAST_OPEN_NO_SYN_DATA_ACK,
+
+    // An attempt to do a fast open failed (FAST_OPEN_SLOW_CONNECT_RETURN)
+    // and we later discovered that the server had nacked initial data.  This
+    // is the expected case results for FAST_OPEN_SLOW_CONNECT_RETURN.
+    FAST_OPEN_NO_SYN_DATA_NACK,
+
+    // An attempt to do a fast open failed (FAST_OPEN_SLOW_CONNECT_RETURN)
+    // and our later probe for ack/nack state failed.
+    FAST_OPEN_NO_SYN_DATA_FAILED,
+
+    FAST_OPEN_MAX_VALUE
+  };
+
+  // Watcher simply forwards notifications to Closure objects set via the
+  // constructor.
+  class Watcher: public base::MessageLoopForIO::Watcher {
+   public:
+    Watcher(const base::Closure& read_ready_callback,
+            const base::Closure& write_ready_callback);
+    virtual ~Watcher();
+
+    // base::MessageLoopForIO::Watcher methods.
+    virtual void OnFileCanReadWithoutBlocking(int fd) OVERRIDE;
+    virtual void OnFileCanWriteWithoutBlocking(int fd) OVERRIDE;
+
+   private:
+    base::Closure read_ready_callback_;
+    base::Closure write_ready_callback_;
+
+    DISALLOW_COPY_AND_ASSIGN(Watcher);
+  };
+
   int AcceptInternal(scoped_ptr<TCPSocketLibevent>* socket,
                      IPEndPoint* address);
 
+  int DoConnect();
+  void DoConnectComplete(int result);
+
+  void LogConnectStart(const AddressList& addresses);
+  void LogConnectCompletion(int net_error);
+
+  void DoReadCallback(int rv);
+  void DoWriteCallback(int rv);
+  void DidCompleteRead();
+  void DidCompleteWrite();
+  void DidCompleteConnect();
+  void DidCompleteConnectOrWrite();
+  void DidCompleteAccept();
+
+  // Internal function to write to a socket. Returns an OS error.
+  int InternalWrite(IOBuffer* buf, int buf_len);
+
+  // Called when the socket is known to be in a connected state.
+  void RecordFastOpenStatus();
+
   int socket_;
 
   base::MessageLoopForIO::FileDescriptorWatcher accept_socket_watcher_;
+  Watcher accept_watcher_;
 
   scoped_ptr<TCPSocketLibevent>* accept_socket_;
   IPEndPoint* accept_address_;
   CompletionCallback accept_callback_;
 
+  base::MessageLoopForIO::FileDescriptorWatcher read_socket_watcher_;
+  base::MessageLoopForIO::FileDescriptorWatcher write_socket_watcher_;
+
+  Watcher read_watcher_;
+  Watcher write_watcher_;
+
+  scoped_refptr<IOBuffer> read_buf_;
+  int read_buf_len_;
+
+  scoped_refptr<IOBuffer> write_buf_;
+  int write_buf_len_;
+
+  // External callback; called when read is complete.
+  CompletionCallback read_callback_;
+
+  // External callback; called when write or connect is complete.
+  CompletionCallback write_callback_;
+
+  // Enables experimental TCP FastOpen option.
+  const bool use_tcp_fastopen_;
+
+  // True when TCP FastOpen is in use and we have done the connect.
+  bool tcp_fastopen_connected_;
+
+  enum FastOpenStatus fast_open_status_;
+
+  // A connect operation is pending. In this case, |write_callback_| needs to be
+  // called when connect is complete.
+  bool waiting_connect_;
+
+  IPEndPoint peer_address_;
+  // The OS error that a connect attempt last completed with.
+  int connect_os_error_;
+
+  bool logging_multiple_connect_attempts_;
+
   BoundNetLog net_log_;
 
   DISALLOW_COPY_AND_ASSIGN(TCPSocketLibevent);
 };
 
 }  // namespace net
 
 #endif  // NET_SOCKET_TCP_SOCKET_LIBEVENT_H_