asio/detail/win_iocp_socket_recv_op.hpp

0001 //
0002 // detail/win_iocp_socket_recv_op.hpp
0003 // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
0004 //
0005 // Copyright (c) 2003-2023 Christopher M. Kohlhoff (chris at kohlhoff dot com)
0006 //
0007 // Distributed under the Boost Software License, Version 1.0. (See accompanying
0008 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0009 //
0010
0011 #ifndef BOOST_ASIO_DETAIL_WIN_IOCP_SOCKET_RECV_OP_HPP
0012 #define BOOST_ASIO_DETAIL_WIN_IOCP_SOCKET_RECV_OP_HPP
0013
0014 #if defined(_MSC_VER) && (_MSC_VER >= 1200)
0015 # pragma once
0016 #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
0017
0018 #include <boost/asio/detail/config.hpp>
0019
0020 #if defined(BOOST_ASIO_HAS_IOCP)
0021
0022 #include <boost/asio/detail/bind_handler.hpp>
0023 #include <boost/asio/detail/buffer_sequence_adapter.hpp>
0024 #include <boost/asio/detail/fenced_block.hpp>
0025 #include <boost/asio/detail/handler_alloc_helpers.hpp>
0026 #include <boost/asio/detail/handler_work.hpp>
0027 #include <boost/asio/detail/memory.hpp>
0028 #include <boost/asio/detail/operation.hpp>
0029 #include <boost/asio/detail/socket_ops.hpp>
0030 #include <boost/asio/error.hpp>
0031
0032 #include <boost/asio/detail/push_options.hpp>
0033
0034 namespace boost {
0035 namespace asio {
0036 namespace detail {
0037
0038 template <typename MutableBufferSequence, typename Handler, typename IoExecutor>
0039 class win_iocp_socket_recv_op : public operation
0040 {
0041 public:
0042   BOOST_ASIO_DEFINE_HANDLER_PTR(win_iocp_socket_recv_op);
0043
0044   win_iocp_socket_recv_op(socket_ops::state_type state,
0045       socket_ops::weak_cancel_token_type cancel_token,
0046       const MutableBufferSequence& buffers, Handler& handler,
0047       const IoExecutor& io_ex)
0048     : operation(&win_iocp_socket_recv_op::do_complete),
0049       state_(state),
0050       cancel_token_(cancel_token),
0051       buffers_(buffers),
0052       handler_(static_cast<Handler&&>(handler)),
0053       work_(handler_, io_ex)
0054   {
0055   }
0056
0057   static void do_complete(void* owner, operation* base,
0058       const boost::system::error_code& result_ec,
0059       std::size_t bytes_transferred)
0060   {
0061     boost::system::error_code ec(result_ec);
0062
0063     // Take ownership of the operation object.
0064     BOOST_ASIO_ASSUME(base != 0);
0065     win_iocp_socket_recv_op* o(static_cast<win_iocp_socket_recv_op*>(base));
0066     ptr p = { boost::asio::detail::addressof(o->handler_), o, o };
0067
0068     BOOST_ASIO_HANDLER_COMPLETION((*o));
0069
0070     // Take ownership of the operation's outstanding work.
0071     handler_work<Handler, IoExecutor> w(
0072         static_cast<handler_work<Handler, IoExecutor>&&>(
0073           o->work_));
0074
0075 #if defined(BOOST_ASIO_ENABLE_BUFFER_DEBUGGING)
0076     // Check whether buffers are still valid.
0077     if (owner)
0078     {
0079       buffer_sequence_adapter<boost::asio::mutable_buffer,
0080           MutableBufferSequence>::validate(o->buffers_);
0081     }
0082 #endif // defined(BOOST_ASIO_ENABLE_BUFFER_DEBUGGING)
0083
0084     socket_ops::complete_iocp_recv(o->state_, o->cancel_token_,
0085         buffer_sequence_adapter<boost::asio::mutable_buffer,
0086           MutableBufferSequence>::all_empty(o->buffers_),
0087         ec, bytes_transferred);
0088
0089     BOOST_ASIO_ERROR_LOCATION(ec);
0090
0091     // Make a copy of the handler so that the memory can be deallocated before
0092     // the upcall is made. Even if we're not about to make an upcall, a
0093     // sub-object of the handler may be the true owner of the memory associated
0094     // with the handler. Consequently, a local copy of the handler is required
0095     // to ensure that any owning sub-object remains valid until after we have
0096     // deallocated the memory here.
0097     detail::binder2<Handler, boost::system::error_code, std::size_t>
0098       handler(o->handler_, ec, bytes_transferred);
0099     p.h = boost::asio::detail::addressof(handler.handler_);
0100     p.reset();
0101
0102     // Make the upcall if required.
0103     if (owner)
0104     {
0105       fenced_block b(fenced_block::half);
0106       BOOST_ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
0107       w.complete(handler, handler.handler_);
0108       BOOST_ASIO_HANDLER_INVOCATION_END;
0109     }
0110   }
0111
0112 private:
0113   socket_ops::state_type state_;
0114   socket_ops::weak_cancel_token_type cancel_token_;
0115   MutableBufferSequence buffers_;
0116   Handler handler_;
0117   handler_work<Handler, IoExecutor> work_;
0118 };
0119
0120 } // namespace detail
0121 } // namespace asio
0122 } // namespace boost
0123
0124 #include <boost/asio/detail/pop_options.hpp>
0125
0126 #endif // defined(BOOST_ASIO_HAS_IOCP)
0127
0128 #endif // BOOST_ASIO_DETAIL_WIN_IOCP_SOCKET_RECV_OP_HPP