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Re: pthred_con_timewait problem

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On Tue, 29 Jan 2013 19:58:03 +0400, Sergei Organov wrote:

> ephlodur <ephlodur@linuxmail.org> writes:
> 
>> On Tue, 29 Jan 2013 15:19:31 +0000, Rainer Weikusat wrote:
>>
>>> ephlodur <ephlodur@linuxmail.org> writes:
>>> 
>>> [...]
>>> 
>>>>         	_ret = pthread_cond_timedwait(&_event_id, &_m_mutex, &ts);
>>>> 			unlock();
>>>>
>>>> but when ever I make that call it always return with EPERM
>>> 
>>> According to the UNIX(*) standard,
>>> 
>>> 	[EPERM]
>>> 		The mutex type is PTHREAD_MUTEX_ERRORCHECK or the mutex
>> is a robust
>>> 		mutex, and the current thread does not own the mutex.
>>> 
>>> This would mean that the thread invoking pthread_cond_timedwait didn't
>>> lock the _m_mutex mutex.
>>
>> As show in my code snippet below from my class CEvent the thread is
>> locl before the call...
>> lock();//lock in this case is define as a base _ret =
>> pthread_cond_timedwait(&_event_id, &_m_mutex, &ts); unlock();
> 
> When you ask for help, it's a good idea to provide minimal example that
> anyone here can compile and run to reproduce the problem.
> 
> When you prepare one, you will probably see what's wrong yourself and
> won't need to ask anybody ;-)
> 
> -- Sergei.

ok here is the code that I'm using but I cannot see the error in 
it ..thank for any help..

the base class for my event
class Lock
{
	private:
		int _ret;
	protected:
		pthread_mutex_t 		_m_mutex;
		pthread_mutexattr_t    	_attr;
		// Prevent copying or assignment
		Lock(const Lock& _arg);
		Lock& operator=(const Lock& _rhs);

	public:
  				Lock(){
				  _ret = pthread_mutexattr_init(&_attr);
				  _ret = pthread_mutexattr_settype
(&_attr, PTHREAD_MUTEX_NORMAL);	  
				  _ret = pthread_mutex_init
(&_m_mutex,&_attr);
					  if(_ret != 0) throw "Error";
				}
		        ~Lock(){
				  pthread_mutex_destroy(&_m_mutex);
				  pthread_mutexattr_destroy(&_attr);
				}
	
		int 	lock(){
				_ret = pthread_mutex_lock(&_m_mutex);
				return _ret;
		}
		
		int 	unlock(){
				_ret = pthread_mutex_unlock(&_m_mutex);
				return _ret;
		}

};

below is my event  class..

class CEvent : public Lock
{
	private:
		struct timespec 	_ts;
		struct timeval    	_tp;
		int 				_ret;
	
	protected:
		pthread_cond_t _event_id;
		pthread_condattr_t cattr; 
		
		// Prevent copying or assignment
		CEvent(const CEvent& _arg);
		CEvent& operator=(const CEvent& _rhs);
	public:
		CEvent(){
              pthread_condattr_init(&cattr); 
			_ret = pthread_condattr_setclock(&cattr, 
CLOCK_MONOTONIC);
			pthread_cond_init(&_event_id,&cattr);
			
		}
		~CEvent(){
			pthread_condattr_destroy(&cattr);
			pthread_cond_destroy(&_event_id);
		}

		int wait(){
			lock();
			_ret = pthread_cond_wait(&_event_id, &_m_mutex);
			unlock();
			return _ret;
		}

		int wait_timeout(int delay)
		{

       		struct timespec ts;
			 clock_gettime(CLOCK_MONOTONIC,&ts);

			ts.tv_sec += delay;
  
			
			lock();
        	_ret = pthread_cond_timedwait(&_event_id, &_m_mutex, &ts);
			unlock();
			return _ret;
		}
			
		int notify(){
			_ret = pthread_cond_signal(&_event_id);
			return _ret;
		}

};

this is my msg queue..

struct gLog_queue
{

	public:
		   void addMsg(LOGMSG *msg) {
			_result = _m_Event.lock();
			_queue.push_back(_msg);
			_result = _m_Event.notify();
			_result = _m_Event.unlock();
		   }

		LOGMSG *getMsg() {
			 _msg = NULL;

			_result = _m_Event.lock();
           	if(_queue.size() != 0)
			{
				_msg = _queue.front();
				_queue.pop_front();
			}
			_result = _m_Event.unlock();

			return _msg;
		}
	
		int wait_for_msg_time(int delay){return _result =  
_m_Event.wait_timeout(delay);}
		
		int wait_for_msg(){return _result = _m_Event.wait();}
			
		int getResult(){return _result;}

	private:
			CEvent				_m_Event;
    		unsigned int    	_count;
			pthread_t	    	_thread_id;
			std::list<LOGMSG* > _queue;
			int 				_result;
			LOGMSG* 			_msg;
};


this is the definition for the log queue
extern struct gLog_queue	app_log_queue;

and this is my call that return EPERM..
ret = app_log_queue.wait_for_msg_time(delay);

Ps: the wait for message work wait_for_msg_time() it he 
wait_for_msg_time_time() does not work..


Thanks again for any help

ephlodur.

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Thread

pthred_con_timewait problem ephlodur <ephlodur@linuxmail.org> - 2013-01-29 14:53 +0000
  Re: pthred_con_timewait problem Rainer Weikusat <rweikusat@mssgmbh.com> - 2013-01-29 15:19 +0000
    Re: pthred_con_timewait problem ephlodur <ephlodur@linuxmail.org> - 2013-01-29 15:28 +0000
      Re: pthred_con_timewait problem Sergei Organov <osv@javad.com> - 2013-01-29 19:58 +0400
        Re: pthred_con_timewait problem ephlodur <ephlodur@linuxmail.org> - 2013-01-29 17:30 +0000
          Re: pthred_con_timewait problem Sergei Organov <osv@javad.com> - 2013-01-29 22:44 +0400
            Re: pthred_con_timewait problem ephlodur <ephlodur@linuxmail.org> - 2013-01-30 11:28 +0000
  Re: pthred_con_timewait problem Richard Kettlewell <rjk@greenend.org.uk> - 2013-01-29 16:32 +0000

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