C++ TCP/IP 네트워킹 (TCP/IP Networking)

TCP/IP 네트워킹 (TCP/IP Networking)

• boost/asio 라이브러리를 이용하여 통신을 할 수 있다.

예제

• 원래 서버 프로그램 하나, 클라이언트 프로그램 하나 이렇게 두 개의 파일을 만드는게 정석이지만, 한번에 보기 편하도록 프로그램 하나로 작성했다.

• 로컬호스트의 13번 포트를 사용하는 예제이다.

  #include <iostream>
  #include <ctime>
  #include <string>
  #include <boost/asio.hpp>
  #include <thread>
  
  using boost::asio::ip::tcp;
  
  void        virtual_server()
  {
    try
    {
      boost::asio::io_service io_service;
  
      tcp::endpoint endpoint(tcp::v4(), 13);
      tcp::acceptor acceptor(io_service, endpoint);
  
      std::cout << "Server - Server started\n";
  
      while (true)
      {
        const std::string message_to_send = "Hello From Server";
  
        tcp::iostream stream;
        boost::system::error_code ec;
  
        std::cout << "Server - Waiting client...\n";
  
        acceptor.accept(*stream.rdbuf(), ec);
  
        std::cout << "Server - Accepted a client\n";
  
        if (!ec)
        {
          std::string line;
          std::getline(stream, line);
          std::cout << "Server - " << line << std::endl;
  
          stream << message_to_send;
          stream << std::endl;
        }
      }
    }
    catch (std::exception& e)
    {
      std::cerr << e.what() << std::endl;
    }
  }
  
  void        virtual_client()
  {
    try
    {
      tcp::iostream stream("127.0.0.1", std::to_string(int(13)));
  
      if (!stream)
      {
        std::cerr << "Client - Fail to connect : " << \
          stream.error().message() << std::endl;
        return ;
      }
  
      std::cout << "Client - Connected to the server\n";
  
      stream << "Hello From Client";
      stream << std::endl;
  
      std::string line;
      std::getline(stream, line);
      std::cout << "Client - " << line << std::endl;
    }
    catch (std::exception& e)
    {
      std::cerr << e.what() << std::endl;
    }
  }
  
  int            main()
  {
    auto t1 = std::thread(virtual_server);
  
    Sleep(1000);
    auto t2 = std::thread(virtual_client);
    t2.join();
  
    Sleep(1000);
    auto t3 = std::thread(virtual_client);
    t3.join();
  
    t1.join();
  }
  
  /* stdout
  Server - Server started
  Server - Waiting client...
  Client - Connected to the server
  Server - Accepted a client
  Server - Hello From Client
  Client - Hello From Server
  Server - Waiting client...
  Client - Connected to the server
  Server - Accepted a client
  Server - Hello From Client
  Client - Hello From Server
  Server - Waiting client...
  */

---

참고

• https://www.boost.org/doc/libs/1_68_0/doc/html/boost_asio/overview/networking/iostreams.html