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//
// echo_server.cpp
// ~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2017 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 <boost/asio/deadline_timer.hpp>
#include <boost/asio/io_context.hpp>
#include <boost/asio/ip/tcp.hpp>
#include <boost/asio/spawn.hpp>
#include <boost/asio/write.hpp>
#include <boost/bind.hpp>
#include <boost/shared_ptr.hpp>
#include <boost/enable_shared_from_this.hpp>
#include <iostream>
using boost::asio::ip::tcp;
class session : public boost::enable_shared_from_this<session>
{
public:
explicit session(boost::asio::io_context& io_context)
: strand_(io_context),
socket_(io_context),
timer_(io_context)
{
}
tcp::socket& socket()
{
return socket_;
}
void go()
{
boost::asio::spawn(strand_,
boost::bind(&session::echo,
shared_from_this(), _1));
boost::asio::spawn(strand_,
boost::bind(&session::timeout,
shared_from_this(), _1));
}
private:
void echo(boost::asio::yield_context yield)
{
try
{
char data[128];
for (;;)
{
timer_.expires_from_now(boost::posix_time::seconds(10));
std::size_t n = socket_.async_read_some(boost::asio::buffer(data), yield);
boost::asio::async_write(socket_, boost::asio::buffer(data, n), yield);
}
}
catch (std::exception& e)
{
socket_.close();
timer_.cancel();
}
}
void timeout(boost::asio::yield_context yield)
{
while (socket_.is_open())
{
boost::system::error_code ignored_ec;
timer_.async_wait(yield[ignored_ec]);
if (timer_.expires_from_now() <= boost::posix_time::seconds(0))
socket_.close();
}
}
boost::asio::io_context::strand strand_;
tcp::socket socket_;
boost::asio::deadline_timer timer_;
};
void do_accept(boost::asio::io_context& io_context,
unsigned short port, boost::asio::yield_context yield)
{
tcp::acceptor acceptor(io_context, tcp::endpoint(tcp::v4(), port));
for (;;)
{
boost::system::error_code ec;
boost::shared_ptr<session> new_session(new session(io_context));
acceptor.async_accept(new_session->socket(), yield[ec]);
if (!ec) new_session->go();
}
}
int main(int argc, char* argv[])
{
try
{
if (argc != 2)
{
std::cerr << "Usage: echo_server <port>\n";
return 1;
}
boost::asio::io_context io_context;
boost::asio::spawn(io_context,
boost::bind(do_accept,
boost::ref(io_context), atoi(argv[1]), _1));
io_context.run();
}
catch (std::exception& e)
{
std::cerr << "Exception: " << e.what() << "\n";
}
return 0;
}
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