1 | // |
2 | // detail/reactive_null_buffers_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_REACTIVE_NULL_BUFFERS_OP_HPP |
12 | #define BOOST_ASIO_DETAIL_REACTIVE_NULL_BUFFERS_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 | #include <boost/asio/detail/addressof.hpp> |
20 | #include <boost/asio/detail/fenced_block.hpp> |
21 | #include <boost/asio/detail/handler_alloc_helpers.hpp> |
22 | #include <boost/asio/detail/handler_invoke_helpers.hpp> |
23 | #include <boost/asio/detail/reactor_op.hpp> |
24 | |
25 | #include <boost/asio/detail/push_options.hpp> |
26 | |
27 | namespace boost { |
28 | namespace asio { |
29 | namespace detail { |
30 | |
31 | template <typename Handler> |
32 | class reactive_null_buffers_op : public reactor_op |
33 | { |
34 | public: |
35 | BOOST_ASIO_DEFINE_HANDLER_PTR(reactive_null_buffers_op); |
36 | |
37 | reactive_null_buffers_op(Handler& handler) |
38 | : reactor_op(&reactive_null_buffers_op::do_perform, |
39 | &reactive_null_buffers_op::do_complete), |
40 | handler_(BOOST_ASIO_MOVE_CAST(Handler)(handler)) |
41 | { |
42 | } |
43 | |
44 | static bool do_perform(reactor_op*) |
45 | { |
46 | return true; |
47 | } |
48 | |
49 | static void do_complete(io_service_impl* owner, operation* base, |
50 | const boost::system::error_code& /*ec*/, |
51 | std::size_t /*bytes_transferred*/) |
52 | { |
53 | // Take ownership of the handler object. |
54 | reactive_null_buffers_op* o(static_cast<reactive_null_buffers_op*>(base)); |
55 | ptr p = { boost::asio::detail::addressof(o->handler_), o, o }; |
56 | |
57 | BOOST_ASIO_HANDLER_COMPLETION((o)); |
58 | |
59 | // Make a copy of the handler so that the memory can be deallocated before |
60 | // the upcall is made. Even if we're not about to make an upcall, a |
61 | // sub-object of the handler may be the true owner of the memory associated |
62 | // with the handler. Consequently, a local copy of the handler is required |
63 | // to ensure that any owning sub-object remains valid until after we have |
64 | // deallocated the memory here. |
65 | detail::binder2<Handler, boost::system::error_code, std::size_t> |
66 | handler(o->handler_, o->ec_, o->bytes_transferred_); |
67 | p.h = boost::asio::detail::addressof(handler.handler_); |
68 | p.reset(); |
69 | |
70 | // Make the upcall if required. |
71 | if (owner) |
72 | { |
73 | fenced_block b(fenced_block::half); |
74 | BOOST_ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_)); |
75 | boost_asio_handler_invoke_helpers::invoke(handler, handler.handler_); |
76 | BOOST_ASIO_HANDLER_INVOCATION_END; |
77 | } |
78 | } |
79 | |
80 | private: |
81 | Handler handler_; |
82 | }; |
83 | |
84 | } // namespace detail |
85 | } // namespace asio |
86 | } // namespace boost |
87 | |
88 | #include <boost/asio/detail/pop_options.hpp> |
89 | |
90 | #endif // BOOST_ASIO_DETAIL_REACTIVE_NULL_BUFFERS_OP_HPP |
91 | |