1 // 2 // detail/null_mutex.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_NULL_MUTEX_HPP 12 #define BOOST_ASIO_DETAIL_NULL_MUTEX_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_HAS_THREADS) 21 22 #include <boost/asio/detail/noncopyable.hpp> 23 #include <boost/asio/detail/scoped_lock.hpp> 24 25 #include <boost/asio/detail/push_options.hpp> 26 27 namespace boost { 28 namespace asio { 29 namespace detail { 30 31 class null_mutex 32 : private noncopyable 33 { 34 public: 35 typedef boost::asio::detail::scoped_lock<null_mutex> scoped_lock; 36 37 // Constructor. null_mutex()38 null_mutex() 39 { 40 } 41 42 // Destructor. ~null_mutex()43 ~null_mutex() 44 { 45 } 46 47 // Lock the mutex. lock()48 void lock() 49 { 50 } 51 52 // Unlock the mutex. unlock()53 void unlock() 54 { 55 } 56 }; 57 58 } // namespace detail 59 } // namespace asio 60 } // namespace boost 61 62 #include <boost/asio/detail/pop_options.hpp> 63 64 #endif // !defined(BOOST_ASIO_HAS_THREADS) 65 66 #endif // BOOST_ASIO_DETAIL_NULL_MUTEX_HPP 67