Port SSLClientSocket to Linux

net/base/tcp_client_socket.h

 // Copyright (c) 2006-2008 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_BASE_TCP_CLIENT_SOCKET_H_
 #define NET_BASE_TCP_CLIENT_SOCKET_H_
 
 #include "build/build_config.h"
 
 #if defined(OS_WIN)
 #include <ws2tcpip.h>
 #include "base/object_watcher.h"
 #elif defined(OS_POSIX)
 struct event;  // From libevent
+#include <sys/socket.h>  // for struct sockaddr
 #define SOCKET int
 #include "base/message_pump_libevent.h"
 #endif
 
 #include "base/scoped_ptr.h"
 #include "net/base/address_list.h"
 #include "net/base/client_socket.h"
 #include "net/base/completion_callback.h"
 
 namespace net {
 
 // A client socket that uses TCP as the transport layer.
 //
-// NOTE: The implementation supports half duplex only.  Read and Write calls
-// must not be in progress at the same time.
+// NOTE: The windows implementation supports half duplex only.  
+// Read and Write calls must not be in progress at the same time.
+// The libevent implementation supports full duplex because that
+// made it slightly easier to implement ssl.
 class TCPClientSocket : public ClientSocket,
 #if defined(OS_WIN)
                         public base::ObjectWatcher::Delegate
 #elif defined(OS_POSIX)
                         public base::MessagePumpLibevent::Watcher
 #endif
 {
  public:
   // The IP address(es) and port number to connect to.  The TCP socket will try
   // each IP address in the list until it succeeds in establishing a
   // connection.
   explicit TCPClientSocket(const AddressList& addresses);
 
   ~TCPClientSocket();
 
   // ClientSocket methods:
   virtual int Connect(CompletionCallback* callback);
   virtual int ReconnectIgnoringLastError(CompletionCallback* callback);
   virtual void Disconnect();
   virtual bool IsConnected() const;
 
   // Socket methods:
-  // Multiple outstanding requests are not supported.  In particular, full
-  // duplex mode (reading and writing at the same time) is not supported.
+  // Multiple outstanding requests are not supported.  
+  // Full duplex mode (reading and writing at the same time) is not supported
+  // on Windows (but is supported on Linux and Mac for ease of implementation
+  // of SSLClientSocket)
   virtual int Read(char* buf, int buf_len, CompletionCallback* callback);
   virtual int Write(const char* buf, int buf_len, CompletionCallback* callback);
 
+#if defined(OS_POSIX)
+  // Identical to posix system call of same name
+  // Needed by ssl_client_socket_nss
+  virtual int GetPeerName(struct sockaddr *name, socklen_t *namelen);
+#endif
+
  private:
   SOCKET socket_;
 
   // The list of addresses we should try in order to establish a connection.
   AddressList addresses_;
 
   // Where we are in above list, or NULL if all addrinfos have been tried.
   const struct addrinfo* current_ai_;
 
+#if defined(OS_WIN)
   enum WaitState {
     NOT_WAITING,
     WAITING_CONNECT,
     WAITING_READ,
     WAITING_WRITE
   };
   WaitState wait_state_;
 
-#if defined(OS_WIN)
   // base::ObjectWatcher::Delegate methods:
   virtual void OnObjectSignaled(HANDLE object);
 
   OVERLAPPED overlapped_;
   WSABUF buffer_;
 
   base::ObjectWatcher watcher_;
+
+  void DidCompleteIO();
 #elif defined(OS_POSIX)
+  // Whether we're currently waiting for connect() to complete
+  bool waiting_connect_;
+
   // The socket's libevent wrapper
   scoped_ptr<event> event_;
 
   // Called by MessagePumpLibevent when the socket is ready to do I/O
   void OnSocketReady(short flags);
 
-  // The buffer used by OnSocketReady to retry Read and Write requests
+  // The buffer used by OnSocketReady to retry Read requests
   char* buf_;
   int buf_len_;
+
+  // The buffer used by OnSocketReady to retry Write requests
+  const char* write_buf_;
+  int write_buf_len_;
+
+  // External callback; called when write is complete.
+  CompletionCallback* write_callback_;
+
+  void DoWriteCallback(int rv);
+  void DidCompleteRead();
+  void DidCompleteWrite();
 #endif
 
-  // External callback; called when read or write is complete.
+  // External callback; called when read (and on Windows, write) is complete.
   CompletionCallback* callback_;
 
   int CreateSocket(const struct addrinfo* ai);
   void DoCallback(int rv);
   void DidCompleteConnect();
-  void DidCompleteIO();
 };
 
 }  // namespace net
 
 #endif  // NET_BASE_TCP_CLIENT_SOCKET_H_