asio/example/cpp11/chat/chat_client.cpp
2019-02-17 19:59:39 -10:00

168 lines
3.6 KiB
C++

//
// chat_client.cpp
// ~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#include <cstdlib>
#include <deque>
#include <iostream>
#include <thread>
#include <boost/asio.hpp>
#include "chat_message.hpp"
using boost::asio::ip::tcp;
typedef std::deque<chat_message> chat_message_queue;
class chat_client
{
public:
chat_client(boost::asio::io_context& io_context,
const tcp::resolver::results_type& endpoints)
: io_context_(io_context),
socket_(io_context)
{
do_connect(endpoints);
}
void write(const chat_message& msg)
{
boost::asio::post(io_context_,
[this, msg]()
{
bool write_in_progress = !write_msgs_.empty();
write_msgs_.push_back(msg);
if (!write_in_progress)
{
do_write();
}
});
}
void close()
{
boost::asio::post(io_context_, [this]() { socket_.close(); });
}
private:
void do_connect(const tcp::resolver::results_type& endpoints)
{
boost::asio::async_connect(socket_, endpoints,
[this](boost::system::error_code ec, tcp::endpoint)
{
if (!ec)
{
do_read_header();
}
});
}
void do_read_header()
{
boost::asio::async_read(socket_,
boost::asio::buffer(read_msg_.data(), chat_message::header_length),
[this](boost::system::error_code ec, std::size_t /*length*/)
{
if (!ec && read_msg_.decode_header())
{
do_read_body();
}
else
{
socket_.close();
}
});
}
void do_read_body()
{
boost::asio::async_read(socket_,
boost::asio::buffer(read_msg_.body(), read_msg_.body_length()),
[this](boost::system::error_code ec, std::size_t /*length*/)
{
if (!ec)
{
std::cout.write(read_msg_.body(), read_msg_.body_length());
std::cout << "\n";
do_read_header();
}
else
{
socket_.close();
}
});
}
void do_write()
{
boost::asio::async_write(socket_,
boost::asio::buffer(write_msgs_.front().data(),
write_msgs_.front().length()),
[this](boost::system::error_code ec, std::size_t /*length*/)
{
if (!ec)
{
write_msgs_.pop_front();
if (!write_msgs_.empty())
{
do_write();
}
}
else
{
socket_.close();
}
});
}
private:
boost::asio::io_context& io_context_;
tcp::socket socket_;
chat_message read_msg_;
chat_message_queue write_msgs_;
};
int main(int argc, char* argv[])
{
try
{
if (argc != 3)
{
std::cerr << "Usage: chat_client <host> <port>\n";
return 1;
}
boost::asio::io_context io_context;
tcp::resolver resolver(io_context);
auto endpoints = resolver.resolve(argv[1], argv[2]);
chat_client c(io_context, endpoints);
std::thread t([&io_context](){ io_context.run(); });
char line[chat_message::max_body_length + 1];
while (std::cin.getline(line, chat_message::max_body_length + 1))
{
chat_message msg;
msg.body_length(std::strlen(line));
std::memcpy(msg.body(), line, msg.body_length());
msg.encode_header();
c.write(msg);
}
c.close();
t.join();
}
catch (std::exception& e)
{
std::cerr << "Exception: " << e.what() << "\n";
}
return 0;
}