1 //
2 // server.cpp
3 // ~~~~~~~~~~
4 //
5 // Copyright (c) 2003-2021 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/bind/bind.hpp>
15 #include <boost/shared_ptr.hpp>
16 #include <boost/enable_shared_from_this.hpp>
17 #include <boost/asio.hpp>
18
19 using boost::asio::ip::tcp;
20
make_daytime_string()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 tcp_connection
29 : public boost::enable_shared_from_this<tcp_connection>
30 {
31 public:
32 typedef boost::shared_ptr<tcp_connection> pointer;
33
create(boost::asio::io_context & io_context)34 static pointer create(boost::asio::io_context& io_context)
35 {
36 return pointer(new tcp_connection(io_context));
37 }
38
socket()39 tcp::socket& socket()
40 {
41 return socket_;
42 }
43
start()44 void start()
45 {
46 message_ = make_daytime_string();
47
48 boost::asio::async_write(socket_, boost::asio::buffer(message_),
49 boost::bind(&tcp_connection::handle_write, shared_from_this(),
50 boost::asio::placeholders::error,
51 boost::asio::placeholders::bytes_transferred));
52 }
53
54 private:
tcp_connection(boost::asio::io_context & io_context)55 tcp_connection(boost::asio::io_context& io_context)
56 : socket_(io_context)
57 {
58 }
59
handle_write(const boost::system::error_code &,size_t)60 void handle_write(const boost::system::error_code& /*error*/,
61 size_t /*bytes_transferred*/)
62 {
63 }
64
65 tcp::socket socket_;
66 std::string message_;
67 };
68
69 class tcp_server
70 {
71 public:
tcp_server(boost::asio::io_context & io_context)72 tcp_server(boost::asio::io_context& io_context)
73 : io_context_(io_context),
74 acceptor_(io_context, tcp::endpoint(tcp::v4(), 13))
75 {
76 start_accept();
77 }
78
79 private:
start_accept()80 void start_accept()
81 {
82 tcp_connection::pointer new_connection =
83 tcp_connection::create(io_context_);
84
85 acceptor_.async_accept(new_connection->socket(),
86 boost::bind(&tcp_server::handle_accept, this, new_connection,
87 boost::asio::placeholders::error));
88 }
89
handle_accept(tcp_connection::pointer new_connection,const boost::system::error_code & error)90 void handle_accept(tcp_connection::pointer new_connection,
91 const boost::system::error_code& error)
92 {
93 if (!error)
94 {
95 new_connection->start();
96 }
97
98 start_accept();
99 }
100
101 boost::asio::io_context& io_context_;
102 tcp::acceptor acceptor_;
103 };
104
main()105 int main()
106 {
107 try
108 {
109 boost::asio::io_context io_context;
110 tcp_server server(io_context);
111 io_context.run();
112 }
113 catch (std::exception& e)
114 {
115 std::cerr << e.what() << std::endl;
116 }
117
118 return 0;
119 }
120