1 // 2 // Copyright (C) 2011 The Android Open Source Project 3 // 4 // Licensed under the Apache License, Version 2.0 (the "License"); 5 // you may not use this file except in compliance with the License. 6 // You may obtain a copy of the License at 7 // 8 // http://www.apache.org/licenses/LICENSE-2.0 9 // 10 // Unless required by applicable law or agreed to in writing, software 11 // distributed under the License is distributed on an "AS IS" BASIS, 12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 // See the License for the specific language governing permissions and 14 // limitations under the License. 15 // 16 17 #ifndef SHILL_ASYNC_CONNECTION_H_ 18 #define SHILL_ASYNC_CONNECTION_H_ 19 20 #include <memory> 21 #include <string> 22 23 #include <base/callback.h> 24 25 #include "shill/refptr_types.h" 26 27 namespace shill { 28 29 class EventDispatcher; 30 class IOHandler; 31 class IPAddress; 32 class Sockets; 33 34 // The AsyncConnection class implements an asynchronous 35 // outgoing TCP connection. When passed an IPAddress and 36 // port, and it will notify the caller when the connection 37 // is made. It can also be passed an interface name to 38 // bind the local side of the connection. 39 class AsyncConnection { 40 public: 41 // If non-empty |interface_name| specifies an local interface from which 42 // to originate the connection. 43 AsyncConnection(const std::string& interface_name, 44 EventDispatcher* dispatcher, 45 Sockets* sockets, 46 const base::Callback<void(bool, int)>& callback); 47 virtual ~AsyncConnection(); 48 49 // Open a connection given an IP address and port (in host order). 50 // When the connection completes, |callback| will be called with the 51 // a boolean (indicating success if true) and an fd of the opened socket 52 // (in the success case). If successful, ownership of this open fd is 53 // passed to the caller on execution of the callback. 54 // 55 // This function (Start) returns true if the connection is in progress, 56 // or if the connection has immediately succeeded (the callback will be 57 // called in this case). On success the callback may be called before 58 // Start() returns to its caller. On failure to start the connection, 59 // this function returns false, but does not execute the callback. 60 // 61 // Calling Start() on an AsyncConnection that is already Start()ed is 62 // an error. 63 virtual bool Start(const IPAddress& address, int port); 64 65 // Stop the open connection, closing any fds that are still owned. 66 // Calling Stop() on an unstarted or Stop()ped AsyncConnection is 67 // a no-op. 68 virtual void Stop(); 69 70 std::string error() const { return error_; } 71 72 private: 73 friend class AsyncConnectionTest; 74 75 void OnConnectCompletion(int fd); 76 77 // Initiate a socket connection to given IP address and port (in host order). 78 int ConnectTo(const IPAddress& address, int port); 79 80 std::string interface_name_; 81 EventDispatcher* dispatcher_; 82 Sockets* sockets_; 83 base::Callback<void(bool, int)> callback_; 84 std::string error_; 85 int fd_; 86 base::Callback<void(int)> connect_completion_callback_; 87 std::unique_ptr<IOHandler> connect_completion_handler_; 88 89 DISALLOW_COPY_AND_ASSIGN(AsyncConnection); 90 }; 91 92 } // namespace shill 93 94 #endif // SHILL_ASYNC_CONNECTION_H_ 95