Function xnSchedulerThreadFunc

Source/OpenNI/XnScheduler.cpp:90–152

This is the actual scheduler function. It is being run in its own thread. */

/* This is the actual scheduler function. It is being run in its own thread. */
XN_THREAD_PROC xnSchedulerThreadFunc(XN_THREAD_PARAM pThreadParam)
{
	XnScheduler* pScheduler = (XnScheduler*)pThreadParam;

	XnUInt64 nNow;
	while (!pScheduler->bStopThread)
	{
		// check when next task should be executed
		XnUInt64 nWait = XN_WAIT_INFINITE;

		XnScheduledTask* pTask = NULL;
		XnTaskCallbackFuncPtr pCallback = NULL;
		void* pCallbackArg = NULL;

		// check if something is in the list
		if (pScheduler->pFirst != NULL)
		{
			// enter critical section
			xnOSEnterCriticalSection(&pScheduler->hCriticalSection);

			pTask = pScheduler->pFirst;
			if (pTask != NULL)
			{
				xnOSGetTimeStamp(&nNow);
				if (pTask->nNextTime < nNow)
				{
					// task should be executed
					pCallback = pTask->pCallback;
					pCallbackArg = pTask->pCallbackArg;

					// remove it from the list
					pScheduler->pFirst = pTask->pNextTask;

					// calculate next time
					pTask->nNextTime += pTask->nInterval;

					// add it to the list again
					xnSchedulerAddTaskInternal(pScheduler, pTask);
				}
				else
				{
					nWait = pTask->nNextTime - nNow;
				}
			}

			// leave critical section
			xnOSLeaveCriticalSection(&pScheduler->hCriticalSection);

			if (pCallback != NULL)
			{
				// execute task (outside critical section)
				pCallback(pCallbackArg);
				// no need to wait (we don't know how much time did callback take)
				nWait = 0;
			}
		}

		// wait for a change of the list, or the time of the next task