| ////////////////////////////////////////////////////////////////////////////// |
| // |
| // (C) Copyright Ion Gaztanaga 2005-2008. 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. |
| // |
| ////////////////////////////////////////////////////////////////////////////// |
| |
| #include <boost/interprocess/detail/posix_time_types_wrk.hpp> |
| |
| namespace boost { |
| |
| namespace interprocess { |
| |
| inline interprocess_mutex::interprocess_mutex() |
| : m_s(0) |
| { |
| //Note that this class is initialized to zero. |
| //So zeroed memory can be interpreted as an |
| //initialized mutex |
| } |
| |
| inline interprocess_mutex::~interprocess_mutex() |
| { |
| //Trivial destructor |
| } |
| |
| inline void interprocess_mutex::lock(void) |
| { |
| do{ |
| boost::uint32_t prev_s = detail::atomic_cas32(const_cast<boost::uint32_t*>(&m_s), 1, 0); |
| |
| if (m_s == 1 && prev_s == 0){ |
| break; |
| } |
| // relinquish current timeslice |
| detail::thread_yield(); |
| }while (true); |
| } |
| |
| inline bool interprocess_mutex::try_lock(void) |
| { |
| boost::uint32_t prev_s = detail::atomic_cas32(const_cast<boost::uint32_t*>(&m_s), 1, 0); |
| return m_s == 1 && prev_s == 0; |
| } |
| |
| inline bool interprocess_mutex::timed_lock(const boost::posix_time::ptime &abs_time) |
| { |
| if(abs_time == boost::posix_time::pos_infin){ |
| this->lock(); |
| return true; |
| } |
| //Obtain current count and target time |
| boost::posix_time::ptime now = microsec_clock::universal_time(); |
| |
| if(now >= abs_time) return false; |
| |
| do{ |
| if(this->try_lock()){ |
| break; |
| } |
| now = microsec_clock::universal_time(); |
| |
| if(now >= abs_time){ |
| return false; |
| } |
| // relinquish current time slice |
| detail::thread_yield(); |
| }while (true); |
| |
| return true; |
| } |
| |
| inline void interprocess_mutex::unlock(void) |
| { detail::atomic_cas32(const_cast<boost::uint32_t*>(&m_s), 0, 1); } |
| |
| } //namespace interprocess { |
| |
| } //namespace boost { |