asio/detail/win_iocp_socket_recvfrom_op.hpp

0001 //
0002 // detail/win_iocp_socket_recvfrom_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_RECVFROM_OP_HPP
0012 #define BOOST_ASIO_DETAIL_WIN_IOCP_SOCKET_RECVFROM_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 Endpoint,
0039     typename Handler, typename IoExecutor>
0040 class win_iocp_socket_recvfrom_op : public operation
0041 {
0042 public:
0043   BOOST_ASIO_DEFINE_HANDLER_PTR(win_iocp_socket_recvfrom_op);
0044
0045   win_iocp_socket_recvfrom_op(Endpoint& endpoint,
0046       socket_ops::weak_cancel_token_type cancel_token,
0047       const MutableBufferSequence& buffers, Handler& handler,
0048       const IoExecutor& io_ex)
0049     : operation(&win_iocp_socket_recvfrom_op::do_complete),
0050       endpoint_(endpoint),
0051       endpoint_size_(static_cast<int>(endpoint.capacity())),
0052       cancel_token_(cancel_token),
0053       buffers_(buffers),
0054       handler_(static_cast<Handler&&>(handler)),
0055       work_(handler_, io_ex)
0056   {
0057   }
0058
0059   int& endpoint_size()
0060   {
0061     return endpoint_size_;
0062   }
0063
0064   static void do_complete(void* owner, operation* base,
0065       const boost::system::error_code& result_ec,
0066       std::size_t bytes_transferred)
0067   {
0068     boost::system::error_code ec(result_ec);
0069
0070     // Take ownership of the operation object.
0071     BOOST_ASIO_ASSUME(base != 0);
0072     win_iocp_socket_recvfrom_op* o(
0073         static_cast<win_iocp_socket_recvfrom_op*>(base));
0074     ptr p = { boost::asio::detail::addressof(o->handler_), o, o };
0075
0076     BOOST_ASIO_HANDLER_COMPLETION((*o));
0077
0078     // Take ownership of the operation's outstanding work.
0079     handler_work<Handler, IoExecutor> w(
0080         static_cast<handler_work<Handler, IoExecutor>&&>(
0081           o->work_));
0082
0083 #if defined(BOOST_ASIO_ENABLE_BUFFER_DEBUGGING)
0084     // Check whether buffers are still valid.
0085     if (owner)
0086     {
0087       buffer_sequence_adapter<boost::asio::mutable_buffer,
0088           MutableBufferSequence>::validate(o->buffers_);
0089     }
0090 #endif // defined(BOOST_ASIO_ENABLE_BUFFER_DEBUGGING)
0091
0092     socket_ops::complete_iocp_recvfrom(o->cancel_token_, ec);
0093
0094     // Record the size of the endpoint returned by the operation.
0095     o->endpoint_.resize(o->endpoint_size_);
0096
0097     BOOST_ASIO_ERROR_LOCATION(ec);
0098
0099     // Make a copy of the handler so that the memory can be deallocated before
0100     // the upcall is made. Even if we're not about to make an upcall, a
0101     // sub-object of the handler may be the true owner of the memory associated
0102     // with the handler. Consequently, a local copy of the handler is required
0103     // to ensure that any owning sub-object remains valid until after we have
0104     // deallocated the memory here.
0105     detail::binder2<Handler, boost::system::error_code, std::size_t>
0106       handler(o->handler_, ec, bytes_transferred);
0107     p.h = boost::asio::detail::addressof(handler.handler_);
0108     p.reset();
0109
0110     // Make the upcall if required.
0111     if (owner)
0112     {
0113       fenced_block b(fenced_block::half);
0114       BOOST_ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
0115       w.complete(handler, handler.handler_);
0116       BOOST_ASIO_HANDLER_INVOCATION_END;
0117     }
0118   }
0119
0120 private:
0121   Endpoint& endpoint_;
0122   int endpoint_size_;
0123   socket_ops::weak_cancel_token_type cancel_token_;
0124   MutableBufferSequence buffers_;
0125   Handler handler_;
0126   handler_work<Handler, IoExecutor> work_;
0127 };
0128
0129 } // namespace detail
0130 } // namespace asio
0131 } // namespace boost
0132
0133 #include <boost/asio/detail/pop_options.hpp>
0134
0135 #endif // defined(BOOST_ASIO_HAS_IOCP)
0136
0137 #endif // BOOST_ASIO_DETAIL_WIN_IOCP_SOCKET_RECVFROM_OP_HPP