doc/html/boost_asio/example/cpp11/spawn/echo_server.cpp
//
// echo_server.cpp
// ~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2018 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/io_context.hpp>
#include <boost/asio/ip/tcp.hpp>
#include <boost/asio/spawn.hpp>
#include <boost/asio/steady_timer.hpp>
#include <boost/asio/write.hpp>
#include <iostream>
#include <memory>
using boost::asio::ip::tcp;
class session : public std::enable_shared_from_this<session>
{
public:
explicit session(tcp::socket socket)
: socket_(std::move(socket)),
timer_(socket_.get_io_context()),
strand_(socket_.get_io_context())
{
}
void go()
{
auto self(shared_from_this());
boost::asio::spawn(strand_,
[this, self](boost::asio::yield_context yield)
{
try
{
char data[128];
for (;;)
{
timer_.expires_from_now(std::chrono::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();
}
});
boost::asio::spawn(strand_,
[this, self](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() <= std::chrono::seconds(0))
socket_.close();
}
});
}
private:
tcp::socket socket_;
boost::asio::steady_timer timer_;
boost::asio::io_context::strand strand_;
};
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::asio::yield_context yield)
{
tcp::acceptor acceptor(io_context,
tcp::endpoint(tcp::v4(), std::atoi(argv[1])));
for (;;)
{
boost::system::error_code ec;
tcp::socket socket(io_context);
acceptor.async_accept(socket, yield[ec]);
if (!ec) std::make_shared<session>(std::move(socket))->go();
}
});
io_context.run();
}
catch (std::exception& e)
{
std::cerr << "Exception: " << e.what() << "\n";
}
return 0;
}