| // |
| // echo_server.cpp |
| // ~~~~~~~~~~~~~~~ |
| // |
| // Copyright (c) 2003-2015 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 <asio/deadline_timer.hpp> |
| #include <asio/io_context.hpp> |
| #include <asio/ip/tcp.hpp> |
| #include <asio/spawn.hpp> |
| #include <asio/write.hpp> |
| #include <boost/bind.hpp> |
| #include <boost/shared_ptr.hpp> |
| #include <boost/enable_shared_from_this.hpp> |
| #include <iostream> |
| |
| using asio::ip::tcp; |
| |
| class session : public boost::enable_shared_from_this<session> |
| { |
| public: |
| explicit session(asio::io_context& io_context) |
| : strand_(io_context), |
| socket_(io_context), |
| timer_(io_context) |
| { |
| } |
| |
| tcp::socket& socket() |
| { |
| return socket_; |
| } |
| |
| void go() |
| { |
| asio::spawn(strand_, |
| boost::bind(&session::echo, |
| shared_from_this(), _1)); |
| asio::spawn(strand_, |
| boost::bind(&session::timeout, |
| shared_from_this(), _1)); |
| } |
| |
| private: |
| void echo(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(asio::buffer(data), yield); |
| asio::async_write(socket_, asio::buffer(data, n), yield); |
| } |
| } |
| catch (std::exception& e) |
| { |
| socket_.close(); |
| timer_.cancel(); |
| } |
| } |
| |
| void timeout(asio::yield_context yield) |
| { |
| while (socket_.is_open()) |
| { |
| asio::error_code ignored_ec; |
| timer_.async_wait(yield[ignored_ec]); |
| if (timer_.expires_from_now() <= boost::posix_time::seconds(0)) |
| socket_.close(); |
| } |
| } |
| |
| asio::io_context::strand strand_; |
| tcp::socket socket_; |
| asio::deadline_timer timer_; |
| }; |
| |
| void do_accept(asio::io_context& io_context, |
| unsigned short port, asio::yield_context yield) |
| { |
| tcp::acceptor acceptor(io_context, tcp::endpoint(tcp::v4(), port)); |
| |
| for (;;) |
| { |
| asio::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; |
| } |
| |
| asio::io_context io_context; |
| |
| 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; |
| } |