1 //
2 // detail/win_iocp_socket_recvfrom_op.hpp
3 // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4 //
5 // Copyright (c) 2003-2015 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 #ifndef BOOST_ASIO_DETAIL_WIN_IOCP_SOCKET_RECVFROM_OP_HPP
12 #define BOOST_ASIO_DETAIL_WIN_IOCP_SOCKET_RECVFROM_OP_HPP
13 
14 #if defined(_MSC_VER) && (_MSC_VER >= 1200)
15 # pragma once
16 #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
17 
18 #include <boost/asio/detail/config.hpp>
19 
20 #if defined(BOOST_ASIO_HAS_IOCP)
21 
22 #include <boost/asio/detail/addressof.hpp>
23 #include <boost/asio/detail/bind_handler.hpp>
24 #include <boost/asio/detail/buffer_sequence_adapter.hpp>
25 #include <boost/asio/detail/fenced_block.hpp>
26 #include <boost/asio/detail/handler_alloc_helpers.hpp>
27 #include <boost/asio/detail/handler_invoke_helpers.hpp>
28 #include <boost/asio/detail/operation.hpp>
29 #include <boost/asio/detail/socket_ops.hpp>
30 #include <boost/asio/error.hpp>
31 
32 #include <boost/asio/detail/push_options.hpp>
33 
34 namespace boost {
35 namespace asio {
36 namespace detail {
37 
38 template <typename MutableBufferSequence, typename Endpoint, typename Handler>
39 class win_iocp_socket_recvfrom_op : public operation
40 {
41 public:
42   BOOST_ASIO_DEFINE_HANDLER_PTR(win_iocp_socket_recvfrom_op);
43 
win_iocp_socket_recvfrom_op(Endpoint & endpoint,socket_ops::weak_cancel_token_type cancel_token,const MutableBufferSequence & buffers,Handler & handler)44   win_iocp_socket_recvfrom_op(Endpoint& endpoint,
45       socket_ops::weak_cancel_token_type cancel_token,
46       const MutableBufferSequence& buffers, Handler& handler)
47     : operation(&win_iocp_socket_recvfrom_op::do_complete),
48       endpoint_(endpoint),
49       endpoint_size_(static_cast<int>(endpoint.capacity())),
50       cancel_token_(cancel_token),
51       buffers_(buffers),
52       handler_(BOOST_ASIO_MOVE_CAST(Handler)(handler))
53   {
54   }
55 
endpoint_size()56   int& endpoint_size()
57   {
58     return endpoint_size_;
59   }
60 
do_complete(io_service_impl * owner,operation * base,const boost::system::error_code & result_ec,std::size_t bytes_transferred)61   static void do_complete(io_service_impl* owner, operation* base,
62       const boost::system::error_code& result_ec,
63       std::size_t bytes_transferred)
64   {
65     boost::system::error_code ec(result_ec);
66 
67     // Take ownership of the operation object.
68     win_iocp_socket_recvfrom_op* o(
69         static_cast<win_iocp_socket_recvfrom_op*>(base));
70     ptr p = { boost::asio::detail::addressof(o->handler_), o, o };
71 
72     BOOST_ASIO_HANDLER_COMPLETION((o));
73 
74 #if defined(BOOST_ASIO_ENABLE_BUFFER_DEBUGGING)
75     // Check whether buffers are still valid.
76     if (owner)
77     {
78       buffer_sequence_adapter<boost::asio::mutable_buffer,
79           MutableBufferSequence>::validate(o->buffers_);
80     }
81 #endif // defined(BOOST_ASIO_ENABLE_BUFFER_DEBUGGING)
82 
83     socket_ops::complete_iocp_recvfrom(o->cancel_token_, ec);
84 
85     // Record the size of the endpoint returned by the operation.
86     o->endpoint_.resize(o->endpoint_size_);
87 
88     // Make a copy of the handler so that the memory can be deallocated before
89     // the upcall is made. Even if we're not about to make an upcall, a
90     // sub-object of the handler may be the true owner of the memory associated
91     // with the handler. Consequently, a local copy of the handler is required
92     // to ensure that any owning sub-object remains valid until after we have
93     // deallocated the memory here.
94     detail::binder2<Handler, boost::system::error_code, std::size_t>
95       handler(o->handler_, ec, bytes_transferred);
96     p.h = boost::asio::detail::addressof(handler.handler_);
97     p.reset();
98 
99     // Make the upcall if required.
100     if (owner)
101     {
102       fenced_block b(fenced_block::half);
103       BOOST_ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
104       boost_asio_handler_invoke_helpers::invoke(handler, handler.handler_);
105       BOOST_ASIO_HANDLER_INVOCATION_END;
106     }
107   }
108 
109 private:
110   Endpoint& endpoint_;
111   int endpoint_size_;
112   socket_ops::weak_cancel_token_type cancel_token_;
113   MutableBufferSequence buffers_;
114   Handler handler_;
115 };
116 
117 } // namespace detail
118 } // namespace asio
119 } // namespace boost
120 
121 #include <boost/asio/detail/pop_options.hpp>
122 
123 #endif // defined(BOOST_ASIO_HAS_IOCP)
124 
125 #endif // BOOST_ASIO_DETAIL_WIN_IOCP_SOCKET_RECVFROM_OP_HPP
126