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//////////////////////////////////////////////////////////////////////////////
//
// (C) Copyright Ion Gaztanaga 2012-2013. 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_SYNC_DETAIL_COMMON_ALGORITHMS_HPP
#define BOOST_INTERPROCESS_SYNC_DETAIL_COMMON_ALGORITHMS_HPP
#if defined(_MSC_VER)
# pragma once
#endif
#include <boost/interprocess/detail/config_begin.hpp>
#include <boost/interprocess/detail/workaround.hpp>
#include <boost/interprocess/sync/spin/wait.hpp>
namespace boost {
namespace interprocess {
namespace ipcdetail {
template<class MutexType>
bool try_based_timed_lock(MutexType &m, const boost::posix_time::ptime &abs_time)
{
//Same as lock()
if(abs_time == boost::posix_time::pos_infin){
m.lock();
return true;
}
//Always try to lock to achieve POSIX guarantees:
// "Under no circumstance shall the function fail with a timeout if the mutex
// can be locked immediately. The validity of the abs_timeout parameter need not
// be checked if the mutex can be locked immediately."
else if(m.try_lock()){
return true;
}
else{
spin_wait swait;
while(microsec_clock::universal_time() < abs_time){
if(m.try_lock()){
return true;
}
swait.yield();
}
return false;
}
}
template<class MutexType>
void try_based_lock(MutexType &m)
{
if(!m.try_lock()){
spin_wait swait;
do{
if(m.try_lock()){
break;
}
else{
swait.yield();
}
}
while(1);
}
}
} //namespace ipcdetail
} //namespace interprocess
} //namespace boost
#include <boost/interprocess/detail/config_end.hpp>
#endif //BOOST_INTERPROCESS_SYNC_DETAIL_COMMON_ALGORITHMS_HPP
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