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

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