ceph/src/boost/libs/asio/example/cpp03/echo/async_tcp_echo_server.cpp

   1 //
   2 // async_tcp_echo_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 <cstdlib>
  12 #include <iostream>
  13 #include <boost/bind.hpp>
  14 #include <boost/asio.hpp>
  15
  16 using boost::asio::ip::tcp;
  17
  18 class session
  19 {
  20 public:
  21   session(boost::asio::io_context& io_context)
  22     : socket_(io_context)
  23   {
  24   }
  25
  26   tcp::socket& socket()
  27   {
  28     return socket_;
  29   }
  30
  31   void start()
  32   {
  33     socket_.async_read_some(boost::asio::buffer(data_, max_length),
  34         boost::bind(&session::handle_read, this,
  35           boost::asio::placeholders::error,
  36           boost::asio::placeholders::bytes_transferred));
  37   }
  38
  39 private:
  40   void handle_read(const boost::system::error_code& error,
  41       size_t bytes_transferred)
  42   {
  43     if (!error)
  44     {
  45       boost::asio::async_write(socket_,
  46           boost::asio::buffer(data_, bytes_transferred),
  47           boost::bind(&session::handle_write, this,
  48             boost::asio::placeholders::error));
  49     }
  50     else
  51     {
  52       delete this;
  53     }
  54   }
  55
  56   void handle_write(const boost::system::error_code& error)
  57   {
  58     if (!error)
  59     {
  60       socket_.async_read_some(boost::asio::buffer(data_, max_length),
  61           boost::bind(&session::handle_read, this,
  62             boost::asio::placeholders::error,
  63             boost::asio::placeholders::bytes_transferred));
  64     }
  65     else
  66     {
  67       delete this;
  68     }
  69   }
  70
  71   tcp::socket socket_;
  72   enum { max_length = 1024 };
  73   char data_[max_length];
  74 };
  75
  76 class server
  77 {
  78 public:
  79   server(boost::asio::io_context& io_context, short port)
  80     : io_context_(io_context),
  81       acceptor_(io_context, tcp::endpoint(tcp::v4(), port))
  82   {
  83     start_accept();
  84   }
  85
  86 private:
  87   void start_accept()
  88   {
  89     session* new_session = new session(io_context_);
  90     acceptor_.async_accept(new_session->socket(),
  91         boost::bind(&server::handle_accept, this, new_session,
  92           boost::asio::placeholders::error));
  93   }
  94
  95   void handle_accept(session* new_session,
  96       const boost::system::error_code& error)
  97   {
  98     if (!error)
  99     {
 100       new_session->start();
 101     }
 102     else
 103     {
 104       delete new_session;
 105     }
 106
 107     start_accept();
 108   }
 109
 110   boost::asio::io_context& io_context_;
 111   tcp::acceptor acceptor_;
 112 };
 113
 114 int main(int argc, char* argv[])
 115 {
 116   try
 117   {
 118     if (argc != 2)
 119     {
 120       std::cerr << "Usage: async_tcp_echo_server <port>\n";
 121       return 1;
 122     }
 123
 124     boost::asio::io_context io_context;
 125
 126     using namespace std; // For atoi.
 127     server s(io_context, atoi(argv[1]));
 128
 129     io_context.run();
 130   }
 131   catch (std::exception& e)
 132   {
 133     std::cerr << "Exception: " << e.what() << "\n";
 134   }
 135
 136   return 0;
 137 }