ceph/src/boost/libs/asio/example/cpp03/tutorial/daytime6/server.cpp

   1 //
   2 // server.cpp
   3 // ~~~~~~~~~~
   4 //
   5 // Copyright (c) 2003-2017 Christopher M. Kohlhoff (chris at kohlhoff dot com)
   6 //
   7 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   8 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   9 //
  10
  11 #include <ctime>
  12 #include <iostream>
  13 #include <string>
  14 #include <boost/array.hpp>
  15 #include <boost/bind.hpp>
  16 #include <boost/shared_ptr.hpp>
  17 #include <boost/asio.hpp>
  18
  19 using boost::asio::ip::udp;
  20
  21 std::string make_daytime_string()
  22 {
  23   using namespace std; // For time_t, time and ctime;
  24   time_t now = time(0);
  25   return ctime(&now);
  26 }
  27
  28 class udp_server
  29 {
  30 public:
  31   udp_server(boost::asio::io_context& io_context)
  32     : socket_(io_context, udp::endpoint(udp::v4(), 13))
  33   {
  34     start_receive();
  35   }
  36
  37 private:
  38   void start_receive()
  39   {
  40     socket_.async_receive_from(
  41         boost::asio::buffer(recv_buffer_), remote_endpoint_,
  42         boost::bind(&udp_server::handle_receive, this,
  43           boost::asio::placeholders::error,
  44           boost::asio::placeholders::bytes_transferred));
  45   }
  46
  47   void handle_receive(const boost::system::error_code& error,
  48       std::size_t /*bytes_transferred*/)
  49   {
  50     if (!error)
  51     {
  52       boost::shared_ptr<std::string> message(
  53           new std::string(make_daytime_string()));
  54
  55       socket_.async_send_to(boost::asio::buffer(*message), remote_endpoint_,
  56           boost::bind(&udp_server::handle_send, this, message,
  57             boost::asio::placeholders::error,
  58             boost::asio::placeholders::bytes_transferred));
  59
  60       start_receive();
  61     }
  62   }
  63
  64   void handle_send(boost::shared_ptr<std::string> /*message*/,
  65       const boost::system::error_code& /*error*/,
  66       std::size_t /*bytes_transferred*/)
  67   {
  68   }
  69
  70   udp::socket socket_;
  71   udp::endpoint remote_endpoint_;
  72   boost::array<char, 1> recv_buffer_;
  73 };
  74
  75 int main()
  76 {
  77   try
  78   {
  79     boost::asio::io_context io_context;
  80     udp_server server(io_context);
  81     io_context.run();
  82   }
  83   catch (std::exception& e)
  84   {
  85     std::cerr << e.what() << std::endl;
  86   }
  87
  88   return 0;
  89 }