C++ WorkItem类代码示例

void WorkQueue::ProcessItems(unsigned threadIndex)
{
    bool wasActive = false;

    for (;;)
    {
        if (shutDown_)
            return;

        if (pausing_ && !wasActive)
            Time::Sleep(0);
        else
        {
            queueMutex_.Acquire();
            if (!queue_.Empty())
            {
                wasActive = true;

                WorkItem* item = queue_.Front();
                queue_.PopFront();
                queueMutex_.Release();
                item->workFunction_(item, threadIndex);
                item->completed_ = true;
            }
            else
            {
                wasActive = false;

                queueMutex_.Release();
                Time::Sleep(0);
            }
        }
    }
}

void* WorkerThread::Entry()
{
	WorkItem* item;

	wxLogMessage( _T( "WorkerThread started" ) );

	while ( !TestDestroy() ) {
		// sleep an hour or until a new WorkItem arrives (DoWork() will wake us up).
		Sleep( 3600 * 1000 );
		while ( !TestDestroy() && ( item = m_workItems.Pop() ) != NULL ) {
			try {
				wxLogMessage( _T( "running WorkItem %p, prio = %d" ), item, item->m_priority );
				item->Run();
			}
			catch ( ... ) {
				// better eat all exceptions thrown by WorkItem::Run(),
				// don't want to let the thread die on a single faulty WorkItem.
				wxLogMessage( _T( "WorkerThread caught exception thrown by WorkItem::Run" ) );
			}
			CleanupWorkItem( item );
			// give other threads some air
			Yield();
		}
	}

	// cleanup leftover WorkItems
	while ( ( item = m_workItems.Pop() ) != NULL ) {
		CleanupWorkItem( item );
	}

	wxLogMessage( _T( "WorkerThread stopped" ) );
	return 0;
}

void WorkItemQueue::Process()
{
	while (!m_dying) {
		WorkItem* item = NULL;
		boost::unique_lock<boost::mutex> lock(m_mutex);
		while ((!m_dying) && (item = Pop())) {
			try {
				//                LslDebug( "running WorkItem %p, prio = %d", item, item->m_priority );
				item->Run();
			} catch (std::exception& e) {
				// better eat all exceptions thrown by WorkItem::Run(),
				// don't want to let the thread die on a single faulty WorkItem.
				LslDebug("WorkerThread caught exception thrown by WorkItem::Run -- %s", e.what());
			} catch (...) {
				LslDebug("WorkerThread caught exception thrown by WorkItem::Run");
			}
			CleanupWorkItem(item);
		}
		// cleanup leftover WorkItems
		while ((item = Pop()) != NULL) {
			CleanupWorkItem(item);
		}
		if (!m_dying)
			//wait for the next Push
			m_cond.wait(lock);
	}
}

 void ReplicationExecutor::doOperationWithGlobalExclusiveLock(
         OperationContext* txn,
         const CallbackHandle& cbHandle) {
     boost::unique_lock<boost::mutex> lk(_mutex);
     if (_inShutdown)
         return;
     const WorkQueue::iterator iter = cbHandle._iter;
     const uint64_t generation = iter->generation;
     invariant(generation == cbHandle._generation);
     WorkItem work = *iter;
     iter->callback = CallbackFn();
     _freeQueue.splice(_freeQueue.begin(), _exclusiveLockInProgressQueue, iter);
     lk.unlock();
     {
         boost::lock_guard<boost::mutex> terribleLock(_terribleExLockSyncMutex);
         work.callback(CallbackData(this,
                                    cbHandle,
                                    (work.isCanceled ?
                                     Status(ErrorCodes::CallbackCanceled, "Callback canceled") :
                                     Status::OK()),
                                    txn));
     }
     lk.lock();
     signalEvent_inlock(work.finishedEvent);
 }

void WorkQueue_Impl::worker_main()
{
	while (true)
	{
		int wakeup_reason = Event::wait(stop_event, work_available_event);
		if (wakeup_reason != 1)
			break;
		MutexSection mutex_lock(&mutex);
		if (!queued_items.empty())
		{
			WorkItem *item = queued_items.front();
			queued_items.erase(queued_items.begin());
			mutex_lock.unlock();
			item->process_work();
			mutex_lock.lock();
			finished_items.push_back(item);
			mutex_lock.unlock();
			set_wakeup_event();
		}
		else
		{
			work_available_event.reset();
		}
	}
}

QTime Job::avgRenderTime(int& days)
{
   QTime sum,diff,midnight;
   QDateTime left,right;
   int tempDays,counter = 0,hour;

   //24*60*60*1000 = 86400000
   const long MS_PER_DAY = 86400000;

   long daySeconds, timeSeconds;
   WorkItem* currentItem = finished.first();
   days = 0;

   //traverse finished list
   while(currentItem)
   {
      left = currentItem->getFinish();
      right = currentItem->getStart();
      diff = left.time() - right.time();

      //if the hours combine to more than 24 add a day
      hour = diff.hour() + sum.hour();
      if(hour >= 24)
         days++;

      //add to sum
      sum = diff + sum;

      //find the days between start time and finish time
      tempDays = right.daysTo(left);

      //if the difference is greater than one day add the difference
      if(tempDays > 0)
      {
         days = days + tempDays - 1;
         if(diff >= midnight)
            days++;
      }

      currentItem = finished.next();
      counter++;
   }

   //now calculate the average.
   //days must be converted into ms
   //sum must be converted into ms
   //the two must be added and devided by counter
   daySeconds = ((double)days/counter)*24*60*60*1000;
   timeSeconds = sum.hour()*60*60*1000 + sum.minute()*60*1000 + sum.second()*1000 + sum.msec();

   if(counter > 0)
      timeSeconds = timeSeconds/counter + daySeconds;
   else
      timeSeconds = 0;

   midnight = midnight.addMSecs(timeSeconds%MS_PER_DAY);

   days = timeSeconds/MS_PER_DAY;
   return midnight;
}

SOM_Scope short  SOMLINK removeItem(Day *somSelf,  Environment *ev,
                                string start, string end, string desc)
{
    DayData *somThis = DayGetData(somSelf);
    short    i;
    WorkItem *item;
    DayMethodDebug("Day","removeItem");

    for (i=0; i < sequenceLength(somThis->workList); i++ )
    {
      item = sequenceElement(somThis->workList,i);

      if ( (strcmp(start, item->_get_startTime(ev)) == 0) &&
           (strcmp(end, item->_get_endTime(ev)) == 0) &&
           (strcmp(desc, item->_get_task(ev)) == 0) )
      {
         sequenceLength(somThis->workList)--;
                                                                         
         for (i; i < sequenceLength(somThis->workList); i++)
         {
           sequenceElement(somThis->workList,i) =
             sequenceElement(somThis->workList, i+1);
         }

         somSelf->sompSetDirty(ev);
         return 0;
      }
    }
    return -1L;       // item not found
}

void ServerObject::jobFailed(const QString& str, QThread* thread)
{
	Thread* thr = (Thread*)thread;
	WorkItem *nextItem;
	if (unpaused) 
	{
		//jobs->renderFailed(((Thread*)thread)->getInfo());
		uint jobid;
		nextItem = jobs->getItem(&jobid);
		
		
		// here is where we queue in the next job in the list
		if (nextItem) {
			emit finished(thr->getHost().append(" ").append(str));
			thr->setJobId(jobid);
			thr->setJobName(nextItem->getJob()->getJobName());
			thr->setInfo(nextItem);
			thr->start();
		}
		else{
			emit finished(thr->getHost().append(" ").append(str));
			emit finished(tr("All jobs finished on ").append(thr->getHost()));
		}
	}
	else {
		emit finished(thr->getHost().append(" ").append("paused"));
	}
}

inline F32 ThreadPool::WorkItemWrapper::getPriority()
{
   WorkItem* item = ptr();
   AssertFatal( item != 0, "ThreadPool::WorkItemWrapper::getPriority - called on dead item" );

   // Compute a scaled priority value based on the item's context.
   return ( item->getContext()->getAccumulatedPriorityBias() * item->getPriority() );
}

    static void Callback(PTP_CALLBACK_INSTANCE, PVOID state, PTP_WORK)
    {
        WorkItem* workItem = static_cast<WorkItem*>(state);

        workItem->callback_();
        ::CloseThreadpoolWork(workItem->work_);
        workItem->selfReferenceSPtr_.reset();
    }

WorkList::~WorkList() {
    // Delete any WorkItems in the queue:
    WorkItem*   item;
    cci_debug_printf("%s", __FUNCTION__);
    char        buf[2048];
    char*       pbuf        = (char*)buf;
    while (remove(&item)) {
        cci_debug_printf("WorkList::~WorkList() deleting %s", item->print(pbuf));
        delete item;
        }

    DeleteCriticalSection(&cs);
    }

void WorkQueue::Complete(unsigned priority)
{
    completing_ = true;

    if (threads_.Size())
    {
        Resume();

        // Take work items also in the main thread until queue empty or no high-priority items anymore
        while (!queue_.Empty())
        {
            queueMutex_.Acquire();
            if (!queue_.Empty() && queue_.Front()->priority_ >= priority)
            {
                WorkItem* item = queue_.Front();
                queue_.PopFront();
                queueMutex_.Release();
                item->workFunction_(item, 0);
                item->completed_ = true;
            }
            else
            {
                queueMutex_.Release();
                break;
            }
        }

        // Wait for threaded work to complete
        while (!IsCompleted(priority))
        {
        }

        // If no work at all remaining, pause worker threads by leaving the mutex locked
        if (queue_.Empty())
            Pause();
    }
    else
    {
        // No worker threads: ensure all high-priority items are completed in the main thread
        while (!queue_.Empty() && queue_.Front()->priority_ >= priority)
        {
            WorkItem* item = queue_.Front();
            queue_.PopFront();
            item->workFunction_(item, 0);
            item->completed_ = true;
        }
    }

    PurgeCompleted(priority);
    completing_ = false;
}

EXTERN_C    int  worklist_remove(long*              rpcmsg,
                                 ccs_pipe_t*        pipe,
                                 k5_ipc_stream*      stream,
                                 time_t*            sst) {
        WorkItem*   item    = NULL;
        cc_int32    err     = worklist.remove(&item);

        *rpcmsg         = item->type();
        *pipe           = item->take_pipe();
        *stream         = item->take_payload();
        *sst            = item->sst();
        delete item;
        return err;
        }

 void* run() {
     // Remove 1 item at a time and process it. Blocks if no items are 
     // available to process.
     for (int i = 0;; i++) {
         printf("thread %lu, loop %d - waiting for item...\n", 
               (long unsigned int)self(), i);
         WorkItem* item = m_queue.remove();
         printf("thread %lu, loop %d - got one item\n", 
               (long unsigned int)self(), i);
         printf("thread %lu, loop %d - item: message - %s, number - %d\n", 
               (long unsigned int)self(), i, item->getMessage(), 
                item->getNumber());
         delete item;
     }
     return NULL;
 }

Job::~Job()
{
   WorkItem* tempItem;
   working.first();
   while(!working.isEmpty())
   {
      tempItem = working.take();

      //set workitems job pointer to null
      tempItem->setParentJob(0);

      //put work items in a special list of WorkQueue class to be deleted
      //when they are finished.
      emit disown(tempItem);
   }
}