boost asio非同步讀寫網路聊天室【官方示例】
阿新 • • 發佈:2019-01-01
// // chat_message.hpp // ~~~~~~~~~~~~~~~~ // // Copyright (c) 2003-2010 Christopher M. Kohlhoff (chris at kohlhoff dot com) // // Distributed under the Boost Software License, Version 1.0. (See accompanying // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) // #pragma warning(disable:4996) #ifndef CHAT_MESSAGE_HPP #define CHAT_MESSAGE_HPP #include <cstdio> #include <cstdlib> #include <cstring> class chat_message { public: enum { header_length = 4 }; enum { max_body_length = 512 }; chat_message() : body_length_(0) { } const char* data() const { return data_; } char* data() { return data_; } size_t length() const { return header_length + body_length_; } const char* body() const { return data_ + header_length; } char* body() { return data_ + header_length; } size_t body_length() const { return body_length_; } void body_length(size_t length) { body_length_ = length; if (body_length_ > max_body_length) body_length_ = max_body_length; } bool decode_header() { using namespace std; // For strncat and atoi. char header[header_length + 1] = ""; strncat(header, data_, header_length); body_length_ = atoi(header); if (body_length_ > max_body_length) { body_length_ = 0; return false; } return true; } void encode_header() { using namespace std; // For sprintf and memcpy. char header[header_length + 1] = ""; sprintf(header, "%4d", body_length_); memcpy(data_, header, header_length); } private: char data_[header_length + max_body_length]; size_t body_length_; }; #endif // CHAT_MESSAGE_HPP
服務端:server.cpp
客戶端:client.cpp// server.cpp : 定義控制檯應用程式的入口點。 // 聊天室程式,支援多個client相互聊天 #include "stdafx.h" // // chat_server.cpp // ~~~~~~~~~~~~~~~ // // Copyright (c) 2003-2010 Christopher M. Kohlhoff (chris at kohlhoff dot com) // // Distributed under the Boost Software License, Version 1.0. (See accompanying // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) // #include <algorithm> #include <cstdlib> #include <deque> #include <iostream> #include <list> #include <set> #include <boost/bind.hpp> #include <boost/shared_ptr.hpp> #include <boost/enable_shared_from_this.hpp> #include <boost/asio.hpp> #include "chat_message.hpp" using boost::asio::ip::tcp; using namespace std; //---------------------------------------------------------------------- typedef std::deque<chat_message> chat_message_queue; //---------------------------------------------------------------------- // 一個抽象類,用於提供聊天室成員的介面 class chat_participant // 聊天參與者 { public: virtual ~chat_participant() {} virtual void deliver(const chat_message& msg) = 0; // 發言 }; typedef boost::shared_ptr<chat_participant> chat_participant_ptr; //---------------------------------------------------------------------- class chat_room // 聊天室 { public: void join(chat_participant_ptr participant) // 6 { cout<<__FUNCTION__<<endl; participants_.insert(participant); // 把聊天室內快取的訊息傳送給新加入的成員,相當於: // chat_message_queue::const_iterator it; // for(it = recent_msgs_.begin(); it!=recent_msgs_.end(); ++it) // participant->deliver(*it); std::for_each(recent_msgs_.begin(), recent_msgs_.end(), boost::bind(&chat_participant::deliver, participant, _1)); // 12 動態繫結 } void leave(chat_participant_ptr participant) { cout<<__FUNCTION__<<endl; participants_.erase(participant); } // 存入msg到緩衝區佇列 void deliver(const chat_message& msg) // 11 發言 { cout<<__FUNCTION__<<endl; recent_msgs_.push_back(msg); while (recent_msgs_.size() > max_recent_msgs) recent_msgs_.pop_front(); // 將過時發言清出緩衝區 // 將新訊息發給每個聊天室成員,相當於: // std::set<chat_participant_ptr>::iterator it; // for(it=participants_.begin(); it!=participants_.end(); ++it) // (*it)->deliver(msg); std::for_each(participants_.begin(), participants_.end(), boost::bind(&chat_participant::deliver, _1, boost::ref(msg))); // 12 } private: std::set<chat_participant_ptr> participants_; // 當前聊天室的n個參與者:set,不能重複 enum { max_recent_msgs = 100 }; // 最大最近訊息:緩衝區最多儲存最近100條發言 chat_message_queue recent_msgs_; // 訊息佇列:deque,先到先出 }; //---------------------------------------------------------------------- // 在聊天室環境下,一個session就是一個成員 class chat_session : public chat_participant, // 繼承 public boost::enable_shared_from_this<chat_session> // 可以使用shared_from_this()(即shared_ptr<chat_session>) { public: chat_session(boost::asio::io_service& io_service, chat_room& room) // 2 7 : socket_(io_service), room_(room) { cout<<__FUNCTION__<<endl; } tcp::socket& socket() // 3 8 { cout<<__FUNCTION__<<endl; return socket_; } void start() // 5 { cout<<__FUNCTION__<<endl; room_.join(shared_from_this()); // 6 room_.join(shared_ptr<chat_session>); // async_read是事件處理一個機制,使用回撥函式從而實現事件處理器方法 // 本示例大量採用這個機制,也就是非同步機制 // 通過回撥函式可以形成一個事件鏈,即在回撥函式中設定一個新的事件與新回撥函式 boost::asio::async_read(socket_, boost::asio::buffer(read_msg_.data(), chat_message::header_length), // 取buffer頭部,正文字元數到read_msg_ boost::bind( &chat_session::handle_read_header, shared_from_this(), // 9 呼叫:shared_from_this()->handle_read_header(boost::asio::placeholders::error); boost::asio::placeholders::error)); } // 存buffer中的資料到read_msg_:header部分 void handle_read_header(const boost::system::error_code& error) // 9 { cout<<__FUNCTION__<<endl; if (!error && read_msg_.decode_header()) { boost::asio::async_read(socket_, boost::asio::buffer(read_msg_.body(), read_msg_.body_length()),// 取buffer文字部分到read_msg_ boost::bind(&chat_session::handle_read_body, shared_from_this(), // 10 呼叫:shared_from_this()->handle_read_body(boost::asio::placeholders::error); boost::asio::placeholders::error)); } else { room_.leave(shared_from_this()); // 14 } } // 存buffer中的資料到read_msg_:body部分 void handle_read_body(const boost::system::error_code& error) // 10 { cout<<__FUNCTION__<<endl; if (!error) { room_.deliver(read_msg_); // 11 boost::asio::async_read(socket_, boost::asio::buffer(read_msg_.data(), chat_message::header_length), // 取buffer頭部,正文字元數到read_msg_ boost::bind(&chat_session::handle_read_header, shared_from_this(),// 呼叫:shared_from_this()->handle_read_header(boost::asio::placeholders::error); boost::asio::placeholders::error)); } else { room_.leave(shared_from_this()); } } //存入資料到write_msgs_,送佇列的最開始一條發言到buffer void deliver(const chat_message& msg) // 12,有幾個客戶端呼叫幾次 { cout<<__FUNCTION__<<endl; bool write_in_progress = !write_msgs_.empty(); write_msgs_.push_back(msg); if (!write_in_progress) { boost::asio::async_write(socket_, boost::asio::buffer(write_msgs_.front().data(), write_msgs_.front().length()), // 佇列的最開始一條發言到buffer boost::bind(&chat_session::handle_write, shared_from_this(), // 13 shared_from_this()->handle_write(boost::asio::placeholders::error) boost::asio::placeholders::error)); } } // 把write_msgs_資料送buffer,使客戶端可以得到,遞迴呼叫自身值到write_msgs_為空 void handle_write(const boost::system::error_code& error) // 13,有幾個客戶端呼叫幾次 { cout<<__FUNCTION__<<endl; if (!error) { write_msgs_.pop_front(); if (!write_msgs_.empty()) { boost::asio::async_write(socket_, boost::asio::buffer(write_msgs_.front().data(),// 佇列的最開始一條發言到buffer write_msgs_.front().length()), boost::bind(&chat_session::handle_write, shared_from_this(),// 13 shared_from_this()->handle_write(boost::asio::placeholders::error) boost::asio::placeholders::error)); } } else { room_.leave(shared_from_this()); } } private: tcp::socket socket_; chat_room& room_; chat_message read_msg_; // 存從buffer讀出的資料 chat_message_queue write_msgs_; // 欲寫入buffer的資料佇列,deque }; typedef boost::shared_ptr<chat_session> chat_session_ptr; //---------------------------------------------------------------------- class chat_server { public: chat_server(boost::asio::io_service& io_service, // 1 const tcp::endpoint& endpoint) : io_service_(io_service), acceptor_(io_service, endpoint) { cout<<__FUNCTION__<<endl; chat_session_ptr new_session(new chat_session(io_service_, room_)); // 2 acceptor_.async_accept(new_session->socket(), // 3 boost::bind(&chat_server::handle_accept, this, new_session, // 4 this->handle_accept(new_session, boost::asio::placeholders::error); boost::asio::placeholders::error)); } // 有連線到來時觸發,然後等待下個連線到來 void handle_accept(chat_session_ptr session, // 4 const boost::system::error_code& error) { cout<<__FUNCTION__<<endl; if (!error) { session->start(); // 5 chat_session_ptr new_session(new chat_session(io_service_, room_)); // 7 acceptor_.async_accept(new_session->socket(), // 8 boost::bind(&chat_server::handle_accept, this, new_session, //this->handle_accept(new_session, boost::asio::placeholders::error); boost::asio::placeholders::error)); } } private: boost::asio::io_service& io_service_; tcp::acceptor acceptor_; chat_room room_; }; typedef boost::shared_ptr<chat_server> chat_server_ptr; typedef std::list<chat_server_ptr> chat_server_list; //---------------------------------------------------------------------- int _tmain(int argc, _TCHAR* argv[]) { // 呼叫棧: // 開啟服務端並等待連線:1-3,acceptor_.async_accept() // 一個客戶端進入並連線:4-8,然後等待下個客戶端:acceptor_.async_accept();又加入一個客戶端:重複呼叫4-8 // 任意客戶端發言:9-13,12\13呼叫n次;任意客戶發言,重複9-13 // 聊天中途又新加入一個客戶端:456 12(n) 78 13(n) // 一個客戶端斷開連線:9 14 // 非同步機制:立刻返回,boost提供的非同步函式字首async_要求一個回撥函式,回撥函式只在某一事件觸發時才被呼叫 // 回撥函式:void your_completion_handler(const boost::system::error_code& ec); try { boost::asio::io_service io_service; chat_server_list servers; // server列表:一個server就是一個聊天室 tcp::endpoint endpoint(/*boost::asio::ip::address_v4::from_string("127.0.0.1")*/tcp::v4(), 1000); chat_server_ptr server(new chat_server(io_service, endpoint)); // 1 servers.push_back(server); io_service.run(); } catch (std::exception& e) { std::cerr << "Exception: " << e.what() << "\n"; } return 0; }
// client.cpp : 定義控制檯應用程式的入口點。 // #include "stdafx.h" // // chat_client.cpp // ~~~~~~~~~~~~~~~ // // Copyright (c) 2003-2010 Christopher M. Kohlhoff (chris at kohlhoff dot com) // // Distributed under the Boost Software License, Version 1.0. (See accompanying // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) // #include <cstdlib> #include <deque> #include <iostream> #include <boost/bind.hpp> #include <boost/asio.hpp> #include <boost/thread.hpp> #include "chat_message.hpp" using boost::asio::ip::tcp; using namespace std; typedef std::deque<chat_message> chat_message_queue; class chat_client { public: chat_client(boost::asio::io_service& io_service, // 1 tcp::resolver::iterator endpoint_iterator) : io_service_(io_service), socket_(io_service) { cout<<__FUNCTION__<<endl; tcp::endpoint endpoint = *endpoint_iterator; socket_.async_connect(endpoint, boost::bind(&chat_client::handle_connect, this, // 2 boost::asio::placeholders::error, ++endpoint_iterator)); } void write(const chat_message& msg) // 5 { cout<<__FUNCTION__<<endl; io_service_.post(boost::bind(&chat_client::do_write, this, msg)); } void close() { cout<<__FUNCTION__<<endl; io_service_.post(boost::bind(&chat_client::do_close, this)); } private: void handle_connect(const boost::system::error_code& error, // 2 tcp::resolver::iterator endpoint_iterator) { cout<<__FUNCTION__<<endl; if (!error) { boost::asio::async_read(socket_, boost::asio::buffer(read_msg_.data(), chat_message::header_length), //copy buffer to read_msg_'s header boost::bind(&chat_client::handle_read_header, this, // 3 boost::asio::placeholders::error)); } else if (endpoint_iterator != tcp::resolver::iterator()) { socket_.close(); tcp::endpoint endpoint = *endpoint_iterator; socket_.async_connect(endpoint, boost::bind(&chat_client::handle_connect, this, // 2 boost::asio::placeholders::error, ++endpoint_iterator)); } } void handle_read_header(const boost::system::error_code& error) // 3 { cout<<__FUNCTION__<<endl; if (!error && read_msg_.decode_header()) { boost::asio::async_read(socket_, boost::asio::buffer(read_msg_.body(), read_msg_.body_length()), //copy buffer to read_msg_'s body boost::bind(&chat_client::handle_read_body, this, // 4 boost::asio::placeholders::error)); } else { do_close(); } } void handle_read_body(const boost::system::error_code& error) // 4 { cout<<__FUNCTION__<<endl; if (!error) { std::cout.write(read_msg_.body(), read_msg_.body_length()); // print read_msg_'s body std::cout << "\n"; boost::asio::async_read(socket_, boost::asio::buffer(read_msg_.data(), chat_message::header_length), boost::bind(&chat_client::handle_read_header, this, // 4 boost::asio::placeholders::error)); } else { do_close(); } } void do_write(chat_message msg) // 6 { cout<<__FUNCTION__<<endl; bool write_in_progress = !write_msgs_.empty(); write_msgs_.push_back(msg); if (!write_in_progress) { boost::asio::async_write(socket_, boost::asio::buffer(write_msgs_.front().data(), write_msgs_.front().length()), // copy write_msgs_.front() to buffer boost::bind(&chat_client::handle_write, this, // 7 send message boost::asio::placeholders::error)); } } void handle_write(const boost::system::error_code& error) // 7 { cout<<__FUNCTION__<<endl; if (!error) { write_msgs_.pop_front(); if (!write_msgs_.empty()) { boost::asio::async_write(socket_, boost::asio::buffer(write_msgs_.front().data(), write_msgs_.front().length()), boost::bind(&chat_client::handle_write, this, // 7 boost::asio::placeholders::error)); } } else { do_close(); } } void do_close() { cout<<__FUNCTION__<<endl; socket_.close(); } private: boost::asio::io_service& io_service_; tcp::socket socket_; chat_message read_msg_; // 存從buffer讀出的資料 chat_message_queue write_msgs_; // 欲寫入buffer的資料佇列,deque }; int _tmain(int argc, _TCHAR* argv[]) { // 呼叫棧: // 開啟客戶端並連線(聊天室沒有對話時):1-2 // 開啟客戶端並連線(聊天室有對話時):1-4 // 自己發言:56734 // 聊天室內其他成員發言:34 try { boost::asio::io_service io_service; tcp::resolver resolver(io_service); tcp::resolver::query query("127.0.0.1", "1000"); // ip port:本機 tcp::resolver::iterator iterator = resolver.resolve(query); chat_client c(io_service, iterator); // 初始化、連線 boost::thread t(boost::bind(&boost::asio::io_service::run, &io_service)); // 執行緒 char line[chat_message::max_body_length + 1]; while (std::cin.getline(line, chat_message::max_body_length + 1)) { chat_message msg; msg.body_length(strlen(line)); memcpy(msg.body(), line, msg.body_length());// line to msg msg.encode_header(); c.write(msg); } c.close(); t.join(); // 執行執行緒 } catch (std::exception& e) { std::cerr << "Exception: " << e.what() << "\n"; } return 0; }
在這裡,為了檢視程式的呼叫過程,在每個成員函式中加了一條:
cout<<__FUNCTION__<<endl;
同時,為了測試方便,固定ip與埠為本機,而不是從main引數中傳遞進來
參考資料:http://blog.csdn.net/cyg0810/article/details/36179195