asio/detail/null_static_mutex.hpp

0001 //
0002 // detail/null_static_mutex.hpp
0003 // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
0004 //
0005 // Copyright (c) 2003-2025 Christopher M. Kohlhoff (chris at kohlhoff dot com)
0006 //
0007 // Distributed under the Boost Software License, Version 1.0. (See accompanying
0008 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0009 //
0010
0011 #ifndef BOOST_ASIO_DETAIL_NULL_STATIC_MUTEX_HPP
0012 #define BOOST_ASIO_DETAIL_NULL_STATIC_MUTEX_HPP
0013
0014 #if defined(_MSC_VER) && (_MSC_VER >= 1200)
0015 # pragma once
0016 #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
0017
0018 #include <boost/asio/detail/config.hpp>
0019
0020 #if !defined(BOOST_ASIO_HAS_THREADS)
0021
0022 #include <boost/asio/detail/scoped_lock.hpp>
0023
0024 #include <boost/asio/detail/push_options.hpp>
0025
0026 namespace boost {
0027 namespace asio {
0028 namespace detail {
0029
0030 struct null_static_mutex
0031 {
0032   typedef boost::asio::detail::scoped_lock<null_static_mutex> scoped_lock;
0033
0034   // Initialise the mutex.
0035   void init()
0036   {
0037   }
0038
0039   // Try to lock the mutex without blocking.
0040   bool try_lock()
0041   {
0042     return true;
0043   }
0044
0045   // Lock the mutex.
0046   void lock()
0047   {
0048   }
0049
0050   // Unlock the mutex.
0051   void unlock()
0052   {
0053   }
0054
0055   int unused_;
0056 };
0057
0058 #define BOOST_ASIO_NULL_STATIC_MUTEX_INIT { 0 }
0059
0060 } // namespace detail
0061 } // namespace asio
0062 } // namespace boost
0063
0064 #include <boost/asio/detail/pop_options.hpp>
0065
0066 #endif // !defined(BOOST_ASIO_HAS_THREADS)
0067
0068 #endif // BOOST_ASIO_DETAIL_NULL_STATIC_MUTEX_HPP