lsst::ap::Condition< MutexT > Class Template Reference

Encapsulates a POSIX condition variable. More...

#include <Condition.h>

Inheritance diagram for lsst::ap::Condition< MutexT >:

Public Types
typedef ScopedLock< MutexT >	Lock

Public Member Functions
	Condition ()
	~Condition ()
void	wait (Lock &lock)
template<typename P >
void	wait (Lock &lock, P predicate)
bool	wait (Lock &lock, TimeSpec const &ts)
template<typename P >
bool	wait (Lock &lock, P predicate, TimeSpec const &deadline)
void	notify ()
void	notifyAll ()
template<>
	Condition ()
template<>
	Condition ()

Private Attributes
::pthread_cond_t	_condition

Detailed Description

template<typename MutexT>
class lsst::ap::Condition< MutexT >

Encapsulates a POSIX condition variable.

Definition at line 50 of file Condition.h.

Member Typedef Documentation

template<typename MutexT >

typedef ScopedLock<MutexT> lsst::ap::Condition< MutexT >::Lock

Definition at line 54 of file Condition.h.

Constructor & Destructor Documentation

template<typename MutexT >

lsst::ap::Condition< MutexT >::Condition

(

)

template<typename MutexT >

lsst::ap::Condition< MutexT >::~Condition ( )

inline

Definition at line 58 of file Condition.h.

                 {
        int result = ::pthread_cond_destroy(&_condition);
        assert(result == 0);
    }

template<>

lsst::ap::Condition< Mutex >::Condition

(

)

Definition at line 50 of file Condition.cc.

                            {
    int err = ::pthread_cond_init(&_condition, 0);
    if (err != 0) {
        throw LSST_EXCEPT(ex::RuntimeError,
            (boost::format("pthread_cond_init() failed, return code: %1%") % err).str());
    }
}

template<>

lsst::ap::Condition< SharedMutex >::Condition

(

)

Definition at line 60 of file Condition.cc.

                                  {
    ::pthread_condattr_t attr;
    int err = ::pthread_condattr_init(&attr);
    if (err != 0) {
        throw LSST_EXCEPT(ex::RuntimeError,
            (boost::format("pthread_condattr_init() failed, return code: %1%") % err).str());
    }
    ScopeGuard attrGuard(boost::bind(::pthread_condattr_destroy, &attr));
    ::pthread_condattr_setpshared(&attr, PTHREAD_PROCESS_SHARED);
    err = ::pthread_cond_init(&_condition, &attr);
    if (err != 0) {
        throw LSST_EXCEPT(ex::RuntimeError,
            (boost::format("pthread_cond_init() failed, return code: %1%") % err).str());
    }
}

Member Function Documentation

template<typename MutexT >

void lsst::ap::Condition< MutexT >::notify ( )

inline

Wakes up at least one thread waiting on the condition. For predictable scheduling, the mutex associated with the condition should be acquired prior to calling this method.

Definition at line 133 of file Condition.h.

                  {
        int result = ::pthread_cond_signal(&_condition);
        assert(result == 0);
    }

template<typename MutexT >

void lsst::ap::Condition< MutexT >::notifyAll ( )

inline

Wakes up all threads waiting on the condition. For predictable scheduling, the mutex associated with the condition should be acquired prior to calling this method.

Definition at line 142 of file Condition.h.

                     {
        int result = ::pthread_cond_broadcast(&_condition);
        assert(result == 0);
    }

template<typename MutexT >

void lsst::ap::Condition< MutexT >::wait ( Lock &  lock )

inline

Waits on the condition variable until the calling thread is woken as a result of another thread calling notify() or notifyAll(). Spurious wakeup can occur.

Precondition

lock has been successfully acquired

Definition at line 69 of file Condition.h.

                           {
        assert(lock.isAcquired());
        int result = ::pthread_cond_wait(&_condition, lock.getPosixMutex());
        assert(result == 0);
    }

template<typename MutexT >

template<typename P >

void lsst::ap::Condition< MutexT >::wait ( Lock &  lock, P  predicate  )

inline

Waits on the condition variable until the given predicate evaluates to true.

Precondition

lock has been successfully acquired

Definition at line 81 of file Condition.h.

    {
        assert(lock.isAcquired());
        while (!predicate()) {
            int result = ::pthread_cond_wait(&_condition, lock.getPosixMutex());
            assert(result == 0);
        }
    }

template<typename MutexT >

bool lsst::ap::Condition< MutexT >::wait ( Lock &  lock, TimeSpec const &  ts  )

inline

Waits on this condition variable until either the given deadline expires or the calling thread is woken as a result of another thread calling notify() or notifyAll(). Spurious wakeup can occur.

Precondition

lock has been successfully acquired

Returns

false if the deadline was missed, and true otherwise.

Definition at line 98 of file Condition.h.

                                                {
        assert(lock.isAcquired());
        int result = ::pthread_cond_timedwait(&_condition, lock.getPosixMutex(), &ts);
        if (result == ETIMEDOUT) {
            return false;
        }
        assert(result == 0);
        return true;
    }

template<typename MutexT >

template<typename P >

bool lsst::ap::Condition< MutexT >::wait ( Lock &  lock, P  predicate, TimeSpec const &  deadline  )

inline

Waits on this condition variable until the given predicate evaluates to true or the given deadline is missed.

Precondition

lock has been successfully acquired

Returns

true if the predicate became true before the deadline expired, and false if the deadline was missed.

Definition at line 117 of file Condition.h.

                                                                   {
        assert(lock.isAcquired());
        while (!predicate()) {
            int result = ::pthread_cond_timedwait(&_condition, lock.getPosixMutex(), &deadline);
            if (result == ETIMEDOUT) {
                return false;
            }
            assert(result == 0);
        }
        return true;
    }

Member Data Documentation

template<typename MutexT >

::pthread_cond_t lsst::ap::Condition< MutexT >::_condition

private

Definition at line 149 of file Condition.h.

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The documentation for this class was generated from the following file:

• /home/lsstsw/stack/Linux64/ap/10.0+224/include/lsst/ap/Condition.h