boost/interprocess/sync/null_mutex.hpp
//////////////////////////////////////////////////////////////////////////////
//
// (C) Copyright Ion Gaztanaga 2005-2012. 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)
//
// See http://www.boost.org/libs/interprocess for documentation.
//
//////////////////////////////////////////////////////////////////////////////
#ifndef BOOST_INTERPROCESS_NULL_MUTEX_HPP
#define BOOST_INTERPROCESS_NULL_MUTEX_HPP
#if (defined _MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif
#include <boost/interprocess/detail/config_begin.hpp>
#include <boost/interprocess/detail/workaround.hpp>
//!\file
//!Describes null_mutex classes
namespace boost {
namespace posix_time
{ class ptime; }
namespace interprocess {
//!Implements a mutex that simulates a mutex without doing any operation and
//!simulates a successful operation.
class null_mutex
{
/// @cond
null_mutex(const null_mutex&);
null_mutex &operator= (const null_mutex&);
/// @endcond
public:
//!Constructor.
//!Empty.
null_mutex(){}
//!Destructor.
//!Empty.
~null_mutex(){}
//!Simulates a mutex lock() operation. Empty function.
void lock(){}
//!Simulates a mutex try_lock() operation.
//!Equivalent to "return true;"
bool try_lock()
{ return true; }
//!Simulates a mutex timed_lock() operation.
//!Equivalent to "return true;"
bool timed_lock(const boost::posix_time::ptime &)
{ return true; }
//!Simulates a mutex unlock() operation.
//!Empty function.
void unlock(){}
//!Simulates a mutex lock_sharable() operation.
//!Empty function.
void lock_sharable(){}
//!Simulates a mutex try_lock_sharable() operation.
//!Equivalent to "return true;"
bool try_lock_sharable()
{ return true; }
//!Simulates a mutex timed_lock_sharable() operation.
//!Equivalent to "return true;"
bool timed_lock_sharable(const boost::posix_time::ptime &)
{ return true; }
//!Simulates a mutex unlock_sharable() operation.
//!Empty function.
void unlock_sharable(){}
//!Simulates a mutex lock_upgradable() operation.
//!Empty function.
void lock_upgradable(){}
//!Simulates a mutex try_lock_upgradable() operation.
//!Equivalent to "return true;"
bool try_lock_upgradable()
{ return true; }
//!Simulates a mutex timed_lock_upgradable() operation.
//!Equivalent to "return true;"
bool timed_lock_upgradable(const boost::posix_time::ptime &)
{ return true; }
//!Simulates a mutex unlock_upgradable() operation.
//!Empty function.
void unlock_upgradable(){}
//!Simulates unlock_and_lock_upgradable().
//!Empty function.
void unlock_and_lock_upgradable(){}
//!Simulates unlock_and_lock_sharable().
//!Empty function.
void unlock_and_lock_sharable(){}
//!Simulates unlock_upgradable_and_lock_sharable().
//!Empty function.
void unlock_upgradable_and_lock_sharable(){}
//Promotions
//!Simulates unlock_upgradable_and_lock().
//!Empty function.
void unlock_upgradable_and_lock(){}
//!Simulates try_unlock_upgradable_and_lock().
//!Equivalent to "return true;"
bool try_unlock_upgradable_and_lock()
{ return true; }
//!Simulates timed_unlock_upgradable_and_lock().
//!Equivalent to "return true;"
bool timed_unlock_upgradable_and_lock(const boost::posix_time::ptime &)
{ return true; }
//!Simulates try_unlock_sharable_and_lock().
//!Equivalent to "return true;"
bool try_unlock_sharable_and_lock()
{ return true; }
//!Simulates try_unlock_sharable_and_lock_upgradable().
//!Equivalent to "return true;"
bool try_unlock_sharable_and_lock_upgradable()
{ return true; }
};
} //namespace interprocess {
} //namespace boost {
#include <boost/interprocess/detail/config_end.hpp>
#endif //BOOST_INTERPROCESS_NULL_MUTEX_HPP