1 //
2 // detail/gcc_sync_fenced_block.hpp
3 // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4 //
5 // Copyright (c) 2003-2021 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_GCC_SYNC_FENCED_BLOCK_HPP
12 #define BOOST_ASIO_DETAIL_GCC_SYNC_FENCED_BLOCK_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(__GNUC__) \
21   && ((__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)) \
22   && !defined(__INTEL_COMPILER) && !defined(__ICL) \
23   && !defined(__ICC) && !defined(__ECC) && !defined(__PATHSCALE__)
24 
25 #include <boost/asio/detail/noncopyable.hpp>
26 
27 #include <boost/asio/detail/push_options.hpp>
28 
29 namespace boost {
30 namespace asio {
31 namespace detail {
32 
33 class gcc_sync_fenced_block
34   : private noncopyable
35 {
36 public:
37   enum half_or_full_t { half, full };
38 
39   // Constructor.
gcc_sync_fenced_block(half_or_full_t)40   explicit gcc_sync_fenced_block(half_or_full_t)
41     : value_(0)
42   {
43     __sync_lock_test_and_set(&value_, 1);
44   }
45 
46   // Destructor.
~gcc_sync_fenced_block()47   ~gcc_sync_fenced_block()
48   {
49     __sync_lock_release(&value_);
50   }
51 
52 private:
53   int value_;
54 };
55 
56 } // namespace detail
57 } // namespace asio
58 } // namespace boost
59 
60 #include <boost/asio/detail/pop_options.hpp>
61 
62 #endif // defined(__GNUC__)
63        // && ((__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4))
64        // && !defined(__INTEL_COMPILER) && !defined(__ICL)
65        // && !defined(__ICC) && !defined(__ECC) && !defined(__PATHSCALE__)
66 
67 #endif // BOOST_ASIO_DETAIL_GCC_SYNC_FENCED_BLOCK_HPP
68