PR_IMPLEMENT(PRStatus) PR_Wait(PRMonitor *mon, PRIntervalTime timeout)
{
PRStatus rv;
PRInt16 saved_entries;
pthread_t saved_owner;
PR_ASSERT(mon != NULL);
/* we'd better be locked */
PR_ASSERT(_PT_PTHREAD_MUTEX_IS_LOCKED(mon->lock.mutex));
/* and the entries better be positive */
PR_ASSERT(mon->entryCount > 0);
/* and it better be by us */
PR_ASSERT(pthread_equal(mon->owner, pthread_self()));
/* tuck these away 'till later */
saved_entries = mon->entryCount;
mon->entryCount = 0;
_PT_PTHREAD_COPY_THR_HANDLE(mon->owner, saved_owner);
_PT_PTHREAD_INVALIDATE_THR_HANDLE(mon->owner);
rv = PR_WaitCondVar(mon->cvar, timeout);
/* reinstate the intresting information */
mon->entryCount = saved_entries;
_PT_PTHREAD_COPY_THR_HANDLE(saved_owner, mon->owner);
return rv;
} /* PR_Wait */
PR_IMPLEMENT(PRStatus) PR_Wait(PRMonitor *mon, PRIntervalTime timeout)
{
PRStatus rv;
PRUint32 saved_entries;
pthread_t saved_owner;
PR_ASSERT(mon != NULL);
rv = pthread_mutex_lock(&mon->lock);
PR_ASSERT(0 == rv);
/* the entries better be positive */
PR_ASSERT(mon->entryCount > 0);
/* and it better be owned by us */
PR_ASSERT(pthread_equal(mon->owner, pthread_self()));
/* tuck these away 'till later */
saved_entries = mon->entryCount;
mon->entryCount = 0;
_PT_PTHREAD_COPY_THR_HANDLE(mon->owner, saved_owner);
_PT_PTHREAD_INVALIDATE_THR_HANDLE(mon->owner);
/*
* If we have pending notifies, post them now.
*
* This is not optimal. We're going to post these notifies
* while we're holding the lock. That means on MP systems
* that they are going to collide for the lock that we will
* hold until we actually wait.
*/
if (0 != mon->notifyTimes)
{
pt_PostNotifiesFromMonitor(&mon->waitCV, mon->notifyTimes);
mon->notifyTimes = 0;
}
rv = pthread_cond_signal(&mon->entryCV);
PR_ASSERT(0 == rv);
if (timeout == PR_INTERVAL_NO_TIMEOUT)
rv = pthread_cond_wait(&mon->waitCV, &mon->lock);
else
rv = pt_TimedWait(&mon->waitCV, &mon->lock, timeout);
PR_ASSERT(0 == rv);
while (mon->entryCount != 0)
{
rv = pthread_cond_wait(&mon->entryCV, &mon->lock);
PR_ASSERT(0 == rv);
}
PR_ASSERT(0 == mon->notifyTimes);
/* reinstate the interesting information */
mon->entryCount = saved_entries;
_PT_PTHREAD_COPY_THR_HANDLE(saved_owner, mon->owner);
rv = pthread_mutex_unlock(&mon->lock);
PR_ASSERT(0 == rv);
return rv;
} /* PR_Wait */
PR_IMPLEMENT(void) PR_EnterMonitor(PRMonitor *mon)
{
pthread_t self = pthread_self();
PRIntn rv;
PR_ASSERT(mon != NULL);
rv = pthread_mutex_lock(&mon->lock);
PR_ASSERT(0 == rv);
if (mon->entryCount != 0)
{
if (pthread_equal(mon->owner, self))
goto done;
while (mon->entryCount != 0)
{
rv = pthread_cond_wait(&mon->entryCV, &mon->lock);
PR_ASSERT(0 == rv);
}
}
/* and now I have the monitor */
PR_ASSERT(0 == mon->notifyTimes);
PR_ASSERT(_PT_PTHREAD_THR_HANDLE_IS_INVALID(mon->owner));
_PT_PTHREAD_COPY_THR_HANDLE(self, mon->owner);
done:
mon->entryCount += 1;
rv = pthread_mutex_unlock(&mon->lock);
PR_ASSERT(0 == rv);
} /* PR_EnterMonitor */
PR_IMPLEMENT(void) PR_EnterMonitor(PRMonitor *mon)
{
pthread_t self = pthread_self();
PR_ASSERT(mon != NULL);
/*
* This is safe only if mon->owner (a pthread_t) can be
* read in one instruction. Perhaps mon->owner should be
* a "PRThread *"?
*/
if (!pthread_equal(mon->owner, self))
{
PR_Lock(&mon->lock);
/* and now I have the lock */
PR_ASSERT(0 == mon->entryCount);
PR_ASSERT(_PT_PTHREAD_THR_HANDLE_IS_INVALID(mon->owner));
_PT_PTHREAD_COPY_THR_HANDLE(self, mon->owner);
}
mon->entryCount += 1;
} /* PR_EnterMonitor */
