Refactor the socket API to remove onEvent callback in socket.create() function.

chrome/browser/extensions/api/socket/udp_socket.h

 // Copyright (c) 2012 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 CHROME_BROWSER_EXTENSIONS_API_SOCKET_UDP_SOCKET_H_
 #define CHROME_BROWSER_EXTENSIONS_API_SOCKET_UDP_SOCKET_H_
 #pragma once
 
 #include <string>
 
 #include "chrome/browser/extensions/api/socket/socket.h"
 #include "net/udp/udp_socket.h"
 
 namespace extensions {
 
 class APIResourceEventNotifier;
 
 class UDPSocket : public Socket {
  public:
   explicit UDPSocket(APIResourceEventNotifier* event_notifier);
   virtual ~UDPSocket();
 
-  virtual int Connect(const std::string& address, int port) OVERRIDE;
+  virtual void Connect(const std::string& address,
+                       int port,
+                       const CompletionCallback& callback) OVERRIDE;
   virtual void Disconnect() OVERRIDE;
   virtual int Bind(const std::string& address, int port) OVERRIDE;
-  virtual int Read(scoped_refptr<net::IOBuffer> io_buffer,
-                   int io_buffer_size) OVERRIDE;
-  virtual int Write(scoped_refptr<net::IOBuffer> io_buffer,
-                    int bytes) OVERRIDE;
-  virtual int RecvFrom(scoped_refptr<net::IOBuffer> io_buffer,
-                       int io_buffer_size,
-                       net::IPEndPoint* address) OVERRIDE;
-  virtual int SendTo(scoped_refptr<net::IOBuffer> io_buffer,
-                     int byte_count,
-                     const std::string& address,
-                     int port) OVERRIDE;
+  virtual void Read(int count,
+                    const ReadCompletionCallback& callback) OVERRIDE;
+  virtual void Write(scoped_refptr<net::IOBuffer> io_buffer,
+                     int bytes,
+                     const CompletionCallback& callback) OVERRIDE;
+  virtual void RecvFrom(int count,
+                        const RecvFromCompletionCallback& callback) OVERRIDE;
+  virtual void SendTo(scoped_refptr<net::IOBuffer> io_buffer,
+                      int byte_count,
+                      const std::string& address,
+                      int port,
+                      const CompletionCallback& callback) OVERRIDE;
 
  private:
+  // Make net::IPEndPoint can be refcounted
+  typedef base::RefCountedData<net::IPEndPoint> IPEndPoint;
+
+  virtual void OnReadComplete(scoped_refptr<net::IOBuffer> io_buffer,
+                              int result);
+  virtual void OnWriteComplete(int result);
+  virtual void OnRecvFromComplete(scoped_refptr<net::IOBuffer> io_buffer,
+                                  scoped_refptr<IPEndPoint> address,
+                                  int result);
+  virtual void OnSendToComplete(int result);
+
   net::UDPSocket socket_;
+
+  ReadCompletionCallback read_callback_;
+
+  CompletionCallback write_callback_;
+
+  RecvFromCompletionCallback recv_from_callback_;
+
+  CompletionCallback send_to_callback_;
 };
 
 }  //  namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_SOCKET_UDP_SOCKET_H_