1 //
2 // detail/socket_select_interrupter.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_SOCKET_SELECT_INTERRUPTER_HPP
12 #define BOOST_ASIO_DETAIL_SOCKET_SELECT_INTERRUPTER_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_WINDOWS_RUNTIME)
21 
22 #if defined(BOOST_ASIO_WINDOWS) \
23   || defined(__CYGWIN__) \
24   || defined(__SYMBIAN32__)
25 
26 #include <boost/asio/detail/socket_types.hpp>
27 
28 #include <boost/asio/detail/push_options.hpp>
29 
30 namespace boost {
31 namespace asio {
32 namespace detail {
33 
34 class socket_select_interrupter
35 {
36 public:
37   // Constructor.
38   BOOST_ASIO_DECL socket_select_interrupter();
39 
40   // Destructor.
41   BOOST_ASIO_DECL ~socket_select_interrupter();
42 
43   // Recreate the interrupter's descriptors. Used after a fork.
44   BOOST_ASIO_DECL void recreate();
45 
46   // Interrupt the select call.
47   BOOST_ASIO_DECL void interrupt();
48 
49   // Reset the select interrupt. Returns true if the call was interrupted.
50   BOOST_ASIO_DECL bool reset();
51 
52   // Get the read descriptor to be passed to select.
read_descriptor() const53   socket_type read_descriptor() const
54   {
55     return read_descriptor_;
56   }
57 
58 private:
59   // Open the descriptors. Throws on error.
60   BOOST_ASIO_DECL void open_descriptors();
61 
62   // Close the descriptors.
63   BOOST_ASIO_DECL void close_descriptors();
64 
65   // The read end of a connection used to interrupt the select call. This file
66   // descriptor is passed to select such that when it is time to stop, a single
67   // byte will be written on the other end of the connection and this
68   // descriptor will become readable.
69   socket_type read_descriptor_;
70 
71   // The write end of a connection used to interrupt the select call. A single
72   // byte may be written to this to wake up the select which is waiting for the
73   // other end to become readable.
74   socket_type write_descriptor_;
75 };
76 
77 } // namespace detail
78 } // namespace asio
79 } // namespace boost
80 
81 #include <boost/asio/detail/pop_options.hpp>
82 
83 #if defined(BOOST_ASIO_HEADER_ONLY)
84 # include <boost/asio/detail/impl/socket_select_interrupter.ipp>
85 #endif // defined(BOOST_ASIO_HEADER_ONLY)
86 
87 #endif // defined(BOOST_ASIO_WINDOWS)
88        // || defined(__CYGWIN__)
89        // || defined(__SYMBIAN32__)
90 
91 #endif // !defined(BOOST_ASIO_WINDOWS_RUNTIME)
92 
93 #endif // BOOST_ASIO_DETAIL_SOCKET_SELECT_INTERRUPTER_HPP
94