ceph/src/boost/libs/asio/example/cpp11/multicast/receiver.cpp

   1 //
   2 // receiver.cpp
   3 // ~~~~~~~~~~~~
   4 //
   5 // Copyright (c) 2003-2020 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 <array>
  12 #include <iostream>
  13 #include <string>
  14 #include <boost/asio.hpp>
  15
  16 constexpr short multicast_port = 30001;
  17
  18 class receiver
  19 {
  20 public:
  21   receiver(boost::asio::io_context& io_context,
  22       const boost::asio::ip::address& listen_address,
  23       const boost::asio::ip::address& multicast_address)
  24     : socket_(io_context)
  25   {
  26     // Create the socket so that multiple may be bound to the same address.
  27     boost::asio::ip::udp::endpoint listen_endpoint(
  28         listen_address, multicast_port);
  29     socket_.open(listen_endpoint.protocol());
  30     socket_.set_option(boost::asio::ip::udp::socket::reuse_address(true));
  31     socket_.bind(listen_endpoint);
  32
  33     // Join the multicast group.
  34     socket_.set_option(
  35         boost::asio::ip::multicast::join_group(multicast_address));
  36
  37     do_receive();
  38   }
  39
  40 private:
  41   void do_receive()
  42   {
  43     socket_.async_receive_from(
  44         boost::asio::buffer(data_), sender_endpoint_,
  45         [this](boost::system::error_code ec, std::size_t length)
  46         {
  47           if (!ec)
  48           {
  49             std::cout.write(data_.data(), length);
  50             std::cout << std::endl;
  51
  52             do_receive();
  53           }
  54         });
  55   }
  56
  57   boost::asio::ip::udp::socket socket_;
  58   boost::asio::ip::udp::endpoint sender_endpoint_;
  59   std::array<char, 1024> data_;
  60 };
  61
  62 int main(int argc, char* argv[])
  63 {
  64   try
  65   {
  66     if (argc != 3)
  67     {
  68       std::cerr << "Usage: receiver <listen_address> <multicast_address>\n";
  69       std::cerr << "  For IPv4, try:\n";
  70       std::cerr << "    receiver 0.0.0.0 239.255.0.1\n";
  71       std::cerr << "  For IPv6, try:\n";
  72       std::cerr << "    receiver 0::0 ff31::8000:1234\n";
  73       return 1;
  74     }
  75
  76     boost::asio::io_context io_context;
  77     receiver r(io_context,
  78         boost::asio::ip::make_address(argv[1]),
  79         boost::asio::ip::make_address(argv[2]));
  80     io_context.run();
  81   }
  82   catch (std::exception& e)
  83   {
  84     std::cerr << "Exception: " << e.what() << "\n";
  85   }
  86
  87   return 0;
  88 }