ceph/src/boost/libs/asio/example/cpp17/coroutines_ts/echo_server.cpp

   1 //
   2 // echo_server.cpp
   3 // ~~~~~~~~~~~~~~~
   4 //
   5 // Copyright (c) 2003-2019 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/co_spawn.hpp>
  12 #include <boost/asio/detached.hpp>
  13 #include <boost/asio/io_context.hpp>
  14 #include <boost/asio/ip/tcp.hpp>
  15 #include <boost/asio/signal_set.hpp>
  16 #include <boost/asio/write.hpp>
  17 #include <cstdio>
  18
  19 using boost::asio::ip::tcp;
  20 using boost::asio::awaitable;
  21 using boost::asio::co_spawn;
  22 using boost::asio::detached;
  23 using boost::asio::use_awaitable;
  24 namespace this_coro = boost::asio::this_coro;
  25
  26 awaitable<void> echo(tcp::socket socket)
  27 {
  28   try
  29   {
  30     char data[1024];
  31     for (;;)
  32     {
  33       std::size_t n = co_await socket.async_read_some(boost::asio::buffer(data), use_awaitable);
  34       co_await async_write(socket, boost::asio::buffer(data, n), use_awaitable);
  35     }
  36   }
  37   catch (std::exception& e)
  38   {
  39     std::printf("echo Exception: %s\n", e.what());
  40   }
  41 }
  42
  43 awaitable<void> listener()
  44 {
  45   auto executor = co_await this_coro::executor;
  46   tcp::acceptor acceptor(executor, {tcp::v4(), 55555});
  47   for (;;)
  48   {
  49     tcp::socket socket = co_await acceptor.async_accept(use_awaitable);
  50     co_spawn(executor,
  51         [socket = std::move(socket)]() mutable
  52         {
  53           return echo(std::move(socket));
  54         },
  55         detached);
  56   }
  57 }
  58
  59 int main()
  60 {
  61   try
  62   {
  63     boost::asio::io_context io_context(1);
  64
  65     boost::asio::signal_set signals(io_context, SIGINT, SIGTERM);
  66     signals.async_wait([&](auto, auto){ io_context.stop(); });
  67
  68     co_spawn(io_context, listener, detached);
  69
  70     io_context.run();
  71   }
  72   catch (std::exception& e)
  73   {
  74     std::printf("Exception: %s\n", e.what());
  75   }
  76 }