1//
2// detail/wait_handler.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_WAIT_HANDLER_HPP
12#define BOOST_ASIO_DETAIL_WAIT_HANDLER_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/wait_op.hpp>
24#include <boost/asio/io_service.hpp>
25
26#include <boost/asio/detail/push_options.hpp>
27
28namespace boost {
29namespace asio {
30namespace detail {
31
32template <typename Handler>
33class wait_handler : public wait_op
34{
35public:
36 BOOST_ASIO_DEFINE_HANDLER_PTR(wait_handler);
37
38 wait_handler(Handler& h)
39 : wait_op(&wait_handler::do_complete),
40 handler_(BOOST_ASIO_MOVE_CAST(Handler)(h))
41 {
42 }
43
44 static void do_complete(io_service_impl* owner, operation* base,
45 const boost::system::error_code& /*ec*/,
46 std::size_t /*bytes_transferred*/)
47 {
48 // Take ownership of the handler object.
49 wait_handler* h(static_cast<wait_handler*>(base));
50 ptr p = { boost::asio::detail::addressof(h->handler_), h, h };
51
52 BOOST_ASIO_HANDLER_COMPLETION((h));
53
54 // Make a copy of the handler so that the memory can be deallocated before
55 // the upcall is made. Even if we're not about to make an upcall, a
56 // sub-object of the handler may be the true owner of the memory associated
57 // with the handler. Consequently, a local copy of the handler is required
58 // to ensure that any owning sub-object remains valid until after we have
59 // deallocated the memory here.
60 detail::binder1<Handler, boost::system::error_code>
61 handler(h->handler_, h->ec_);
62 p.h = boost::asio::detail::addressof(handler.handler_);
63 p.reset();
64
65 // Make the upcall if required.
66 if (owner)
67 {
68 fenced_block b(fenced_block::half);
69 BOOST_ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_));
70 boost_asio_handler_invoke_helpers::invoke(handler, handler.handler_);
71 BOOST_ASIO_HANDLER_INVOCATION_END;
72 }
73 }
74
75private:
76 Handler handler_;
77};
78
79} // namespace detail
80} // namespace asio
81} // namespace boost
82
83#include <boost/asio/detail/pop_options.hpp>
84
85#endif // BOOST_ASIO_DETAIL_WAIT_HANDLER_HPP
86

source code of boost/boost/asio/detail/wait_handler.hpp