78 lines
2.0 KiB
C++
Executable File
78 lines
2.0 KiB
C++
Executable File
//////////////////////////////////////////////////////////////////////////////
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//
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// (C) Copyright Ion Gaztanaga 2005-2008. Distributed under the Boost
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// Software License, Version 1.0. (See accompanying file
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// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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//
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// See http://www.boost.org/libs/interprocess for documentation.
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//
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//////////////////////////////////////////////////////////////////////////////
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#include <boost/interprocess/detail/posix_time_types_wrk.hpp>
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namespace boost {
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namespace interprocess {
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inline interprocess_mutex::interprocess_mutex()
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: m_s(0)
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{
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//Note that this class is initialized to zero.
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//So zeroed memory can be interpreted as an
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//initialized mutex
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}
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inline interprocess_mutex::~interprocess_mutex()
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{
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//Trivial destructor
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}
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inline void interprocess_mutex::lock(void)
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{
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do{
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boost::uint32_t prev_s = detail::atomic_cas32((boost::uint32_t*)&m_s, 1, 0);
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if (m_s == 1 && prev_s == 0){
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break;
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}
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// relinquish current timeslice
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detail::thread_yield();
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}while (true);
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}
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inline bool interprocess_mutex::try_lock(void)
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{
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boost::uint32_t prev_s = detail::atomic_cas32((boost::uint32_t*)&m_s, 1, 0);
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return m_s == 1 && prev_s == 0;
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}
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inline bool interprocess_mutex::timed_lock(const boost::posix_time::ptime &abs_time)
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{
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//Obtain current count and target time
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boost::posix_time::ptime now = microsec_clock::universal_time();
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if(now >= abs_time) return false;
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do{
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if(this->try_lock()){
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break;
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}
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now = microsec_clock::universal_time();
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if(now >= abs_time){
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return false;
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}
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// relinquish current time slice
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detail::thread_yield();
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}while (true);
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return true;
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}
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inline void interprocess_mutex::unlock(void)
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{ detail::atomic_cas32((boost::uint32_t*)&m_s, 0, 1); }
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} //namespace interprocess {
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} //namespace boost {
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