| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566 | //// detail/null_mutex.hpp// ~~~~~~~~~~~~~~~~~~~~~//// Copyright (c) 2003-2020 Christopher M. Kohlhoff (chris at kohlhoff dot com)//// Distributed under the Boost Software License, Version 1.0. (See accompanying// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)//#ifndef BOOST_ASIO_DETAIL_NULL_MUTEX_HPP#define BOOST_ASIO_DETAIL_NULL_MUTEX_HPP#if defined(_MSC_VER) && (_MSC_VER >= 1200)# pragma once#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)#include <boost/asio/detail/config.hpp>#if !defined(BOOST_ASIO_HAS_THREADS)#include <boost/asio/detail/noncopyable.hpp>#include <boost/asio/detail/scoped_lock.hpp>#include <boost/asio/detail/push_options.hpp>namespace boost {namespace asio {namespace detail {class null_mutex  : private noncopyable{public:  typedef boost::asio::detail::scoped_lock<null_mutex> scoped_lock;  // Constructor.  null_mutex()  {  }  // Destructor.  ~null_mutex()  {  }  // Lock the mutex.  void lock()  {  }  // Unlock the mutex.  void unlock()  {  }};} // namespace detail} // namespace asio} // namespace boost#include <boost/asio/detail/pop_options.hpp>#endif // !defined(BOOST_ASIO_HAS_THREADS)#endif // BOOST_ASIO_DETAIL_NULL_MUTEX_HPP
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