//////////////////////////////////////////////////////////////////////////////
 //
 // (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
 
 #ifndef BOOST_CONFIG_HPP
 #  include <boost/config.hpp>
 #endif
 #
 #if defined(BOOST_HAS_PRAGMA_ONCE)
 #  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.is_pos_infinity()){
       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);
    }
 }
 
 template<class MutexType>
 void timeout_when_locking_aware_lock(MutexType &m)
 {
    #ifdef BOOST_INTERPROCESS_ENABLE_TIMEOUT_WHEN_LOCKING
       boost::posix_time::ptime wait_time
          = microsec_clock::universal_time()
          + boost::posix_time::milliseconds(BOOST_INTERPROCESS_TIMEOUT_WHEN_LOCKING_DURATION_MS);
       if (!m.timed_lock(wait_time))
       {
          throw interprocess_exception(timeout_when_locking_error
                                      , "Interprocess mutex timeout when locking. Possible deadlock: "
                                        "owner died without unlocking?");
       }
    #else
       m.lock();
    #endif
 }
 
 }  //namespace ipcdetail
 }  //namespace interprocess
 }  //namespace boost
 
 #include <boost/interprocess/detail/config_end.hpp>
 
 #endif   //BOOST_INTERPROCESS_SYNC_DETAIL_COMMON_ALGORITHMS_HPP