提升asio http服務器，怎么停？

Question

我正在使用boost附帶的一個示例http服務器（在doc / html / boost_asio / example / cpp03 / http / server，或者在http://www.boost.org/doc/libs/1_55_0/） doc / html / boost_asio / examples / cpp03_examples.html＃boost_asio.examples.cpp03_examples.http_server ）。

該示例打開一個接受器套接字並偵聽，剝離請求對象的請求。 服務器還有一個boost asio signal_set ，用於注冊信號處理程序，並在收到SIGINT或SIGTERM時取消io_service中的所有asio請求。 按CTRL-C並收到信號， io_service調用handle_stop()函數，然后在所有asio::ip::tcp::sockets上調用.close() 。 整個服務器正常關閉， io_service.run()調用退出，程序結束。

我希望能夠在一個線程中啟動這個http服務器，然后以編程方式取消它而不是使用信號。 這樣做的可接受方式是什么？ 我刪除了signal_set和信號處理程序，然后在另一個線程上啟動了服務器。 它可以很好地處理來自新線程的http請求。 如何從另一個線程中阻止它？ 從另一個線程調用asio::ip::tcp::socket::close()是否安全？ 文檔不清楚，只是這樣做感覺非常，非asio-ish。 實際上，當我嘗試這樣做時，只要我還沒有接受任何http請求，它就能正常工作。 如果我甚至處理了一個http請求，那么進程會在boost中崩潰：

>   test_ssl_server_sa.exe!boost::detail::sp_counted_base::add_ref_lock()  Line 81 + 0x3 bytes  C++
    test_ssl_server_sa.exe!boost::detail::shared_count::shared_count(const boost::detail::weak_count & r={...})  Line 578 + 0x12 bytes  C++
    test_ssl_server_sa.exe!boost::shared_ptr<http::server::connection>::shared_ptr<http::server::connection><http::server::connection>(const boost::weak_ptr<http::server::connection> & r={...})  Line 405 + 0x3f bytes    C++
    test_ssl_server_sa.exe!boost::enable_shared_from_this<http::server::connection>::shared_from_this()  Line 49 + 0xc bytes    C++
    test_ssl_server_sa.exe!http::server::connection::handle_handshake(const boost::system::error_code & error={...})  Line 83 + 0x11 bytes  C++
    test_ssl_server_sa.exe!boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>::operator()(http::server::connection * p=0x004b8fe8, const boost::system::error_code & a1={...})  Line 165 + 0x18 bytes    C++
    test_ssl_server_sa.exe!boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> >::operator()<boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list1<boost::system::error_code const &> >(boost::_bi::type<void> __formal={...}, boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &> & f={...}, boost::_bi::list1<boost::system::error_code const &> & a={...}, boost::_bi::type<void> __formal={...})  Line 314    C++
    test_ssl_server_sa.exe!boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > >::operator()<boost::system::error_code>(const boost::system::error_code & a1={...})  Line 48  C++
    test_ssl_server_sa.exe!boost::asio::ssl::detail::handshake_op::call_handler<boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > >(boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > & handler={...}, const boost::system::error_code & ec={...}, const unsigned int & __formal=0)  Line 55    C++
    test_ssl_server_sa.exe!boost::asio::ssl::detail::io_op<boost::asio::basic_stream_socket<boost::asio::ip::tcp,boost::asio::stream_socket_service<boost::asio::ip::tcp> >,boost::asio::ssl::detail::handshake_op,boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > >::operator()(boost::system::error_code ec={...}, unsigned int bytes_transferred=0, int start=0)  Line 276   C++
    test_ssl_server_sa.exe!boost::asio::detail::binder2<boost::asio::ssl::detail::io_op<boost::asio::basic_stream_socket<boost::asio::ip::tcp,boost::asio::stream_socket_service<boost::asio::ip::tcp> >,boost::asio::ssl::detail::handshake_op,boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > >,boost::system::error_code,unsigned int>::operator()()  Line 129   C++
    test_ssl_server_sa.exe!boost::asio::asio_handler_invoke<boost::asio::detail::binder2<boost::asio::ssl::detail::io_op<boost::asio::basic_stream_socket<boost::asio::ip::tcp,boost::asio::stream_socket_service<boost::asio::ip::tcp> >,boost::asio::ssl::detail::handshake_op,boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > >,boost::system::error_code,unsigned int> >(boost::asio::detail::binder2<boost::asio::ssl::detail::io_op<boost::asio::basic_stream_socket<boost::asio::ip::tcp,boost::asio::stream_socket_service<boost::asio::ip::tcp> >,boost::asio::ssl::detail::handshake_op,boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > >,boost::system::error_code,unsigned int> & function={...}, ...)  Line 70 C++
    test_ssl_server_sa.exe!boost_asio_handler_invoke_helpers::invoke<boost::asio::detail::binder2<boost::asio::ssl::detail::io_op<boost::asio::basic_stream_socket<boost::asio::ip::tcp,boost::asio::stream_socket_service<boost::asio::ip::tcp> >,boost::asio::ssl::detail::handshake_op,boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > >,boost::system::error_code,unsigned int>,boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > >(boost::asio::detail::binder2<boost::asio::ssl::detail::io_op<boost::asio::basic_stream_socket<boost::asio::ip::tcp,boost::asio::stream_socket_service<boost::asio::ip::tcp> >,boost::asio::ssl::detail::handshake_op,boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > >,boost::system::error_code,unsigned int> & function={...}, boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > & context={...})  Line 37 + 0x16 bytes   C++
    test_ssl_server_sa.exe!boost::asio::ssl::detail::asio_handler_invoke<boost::asio::detail::binder2<boost::asio::ssl::detail::io_op<boost::asio::basic_stream_socket<boost::asio::ip::tcp,boost::asio::stream_socket_service<boost::asio::ip::tcp> >,boost::asio::ssl::detail::handshake_op,boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > >,boost::system::error_code,unsigned int>,boost::asio::basic_stream_socket<boost::asio::ip::tcp,boost::asio::stream_socket_service<boost::asio::ip::tcp> >,boost::asio::ssl::detail::handshake_op,boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > >(boost::asio::detail::binder2<boost::asio::ssl::detail::io_op<boost::asio::basic_stream_socket<boost::asio::ip::tcp,boost::asio::stream_socket_service<boost::asio::ip::tcp> >,boost::asio::ssl::detail::handshake_op,boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > >,boost::system::error_code,unsigned int> & function={...}, boost::asio::ssl::detail::io_op<boost::asio::basic_stream_socket<boost::asio::ip::tcp,boost::asio::stream_socket_service<boost::asio::ip::tcp> >,boost::asio::ssl::detail::handshake_op,boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > > * this_handler=0x00fefb70)  Line 319 + 0x10 bytes  C++
    test_ssl_server_sa.exe!boost_asio_handler_invoke_helpers::invoke<boost::asio::detail::binder2<boost::asio::ssl::detail::io_op<boost::asio::basic_stream_socket<boost::asio::ip::tcp,boost::asio::stream_socket_service<boost::asio::ip::tcp> >,boost::asio::ssl::detail::handshake_op,boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > >,boost::system::error_code,unsigned int>,boost::asio::ssl::detail::io_op<boost::asio::basic_stream_socket<boost::asio::ip::tcp,boost::asio::stream_socket_service<boost::asio::ip::tcp> >,boost::asio::ssl::detail::handshake_op,boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > > >(boost::asio::detail::binder2<boost::asio::ssl::detail::io_op<boost::asio::basic_stream_socket<boost::asio::ip::tcp,boost::asio::stream_socket_service<boost::asio::ip::tcp> >,boost::asio::ssl::detail::handshake_op,boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > >,boost::system::error_code,unsigned int> & function={...}, boost::asio::ssl::detail::io_op<boost::asio::basic_stream_socket<boost::asio::ip::tcp,boost::asio::stream_socket_service<boost::asio::ip::tcp> >,boost::asio::ssl::detail::handshake_op,boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > > & context={...})  Line 37 + 0x16 bytes   C++
    test_ssl_server_sa.exe!boost::asio::detail::reactive_socket_recv_op<boost::asio::mutable_buffers_1,boost::asio::ssl::detail::io_op<boost::asio::basic_stream_socket<boost::asio::ip::tcp,boost::asio::stream_socket_service<boost::asio::ip::tcp> >,boost::asio::ssl::detail::handshake_op,boost::_bi::bind_t<void,boost::_mfi::mf1<void,http::server::connection,boost::system::error_code const &>,boost::_bi::list2<boost::_bi::value<http::server::connection *>,boost::arg<1> > > > >::do_complete(boost::asio::detail::task_io_service * owner=0x00c1aca0, boost::asio::detail::task_io_service_operation * base=0x00c1f948, const boost::system::error_code & __formal={...}, const boost::system::error_code & __formal={...})  Line 110 + 0xd bytes    C++
    test_ssl_server_sa.exe!boost::asio::detail::task_io_service_operation::complete(boost::asio::detail::task_io_service & owner={...}, const boost::system::error_code & ec={...}, unsigned int bytes_transferred=0)  Line 38 + 0x1a bytes C++
    test_ssl_server_sa.exe!boost::asio::detail::task_io_service::do_run_one(boost::asio::detail::scoped_lock<boost::asio::detail::win_mutex> & lock={...}, boost::asio::detail::task_io_service_thread_info & this_thread={...}, const boost::system::error_code & ec={...})  Line 386  C++
    test_ssl_server_sa.exe!boost::asio::detail::task_io_service::run(boost::system::error_code & ec={...})  Line 153 + 0x1e bytes   C++

我不是說服務器可能沒有不同的同步問題 - 特別是，它看起來像服務器崩潰了對boost::shared_ptr多次訪問連接對象。 但是我對從另一個線程關閉asio io_service.run()調用的正確方法更感興趣。 當我想象我希望如何工作時，我想象一個等待控制變量的io_service請求。 如果我想關閉服務器，我會從另一個線程發出控制變量的信號，而io_service會在io_service線程上調用我的回調。 從那里，它可以.close()任何套接字或以其他方式取消任何其他飛行中的請求。

Answer 1

您可以使用boost :: asio :: io_service :: post與線程中的lambda嘗試停止http服務器。 lambda將在http服務器線程中執行。 它可以安全地在所有套接字上調用socket :: close。 這將優雅地停止服務。