1 //
2 // daytime_client.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 <boost/asio.hpp>
12 #include <boost/bind/bind.hpp>
13 #include <iostream>
14 #include "logger.hpp"
15
16 using boost::asio::ip::tcp;
17
18 char read_buffer[1024];
19
read_handler(const boost::system::error_code & e,std::size_t bytes_transferred,tcp::socket * s)20 void read_handler(const boost::system::error_code& e,
21 std::size_t bytes_transferred, tcp::socket* s)
22 {
23 if (!e)
24 {
25 std::cout.write(read_buffer, bytes_transferred);
26
27 s->async_read_some(boost::asio::buffer(read_buffer),
28 boost::bind(read_handler, boost::asio::placeholders::error,
29 boost::asio::placeholders::bytes_transferred, s));
30 }
31 else
32 {
33 boost::asio::execution_context& context = boost::asio::query(
34 s->get_executor(), boost::asio::execution::context);
35 services::logger logger(context, "read_handler");
36
37 std::string msg = "Read error: ";
38 msg += e.message();
39 logger.log(msg);
40 }
41 }
42
connect_handler(const boost::system::error_code & e,tcp::socket * s)43 void connect_handler(const boost::system::error_code& e, tcp::socket* s)
44 {
45 boost::asio::execution_context& context = boost::asio::query(
46 s->get_executor(), boost::asio::execution::context);
47 services::logger logger(context, "connect_handler");
48
49 if (!e)
50 {
51 logger.log("Connection established");
52
53 s->async_read_some(boost::asio::buffer(read_buffer),
54 boost::bind(read_handler, boost::asio::placeholders::error,
55 boost::asio::placeholders::bytes_transferred, s));
56 }
57 else
58 {
59 std::string msg = "Unable to establish connection: ";
60 msg += e.message();
61 logger.log(msg);
62 }
63 }
64
main(int argc,char * argv[])65 int main(int argc, char* argv[])
66 {
67 try
68 {
69 if (argc != 2)
70 {
71 std::cerr << "Usage: daytime_client <host>" << std::endl;
72 return 1;
73 }
74
75 boost::asio::io_context io_context;
76
77 // Set the name of the file that all logger instances will use.
78 services::logger logger(io_context, "");
79 logger.use_file("log.txt");
80
81 // Resolve the address corresponding to the given host.
82 tcp::resolver resolver(io_context);
83 tcp::resolver::results_type endpoints =
84 resolver.resolve(argv[1], "daytime");
85
86 // Start an asynchronous connect.
87 tcp::socket socket(io_context);
88 boost::asio::async_connect(socket, endpoints,
89 boost::bind(connect_handler,
90 boost::asio::placeholders::error, &socket));
91
92 // Run the io_context until all operations have finished.
93 io_context.run();
94 }
95 catch (std::exception& e)
96 {
97 std::cerr << e.what() << std::endl;
98 }
99
100 return 0;
101 }
102