Tcl Source Code

 */

typedef struct ThreadSpecificData {
    Tcl_Event *firstEventPtr;	/* First pending event, or NULL if none. */
    Tcl_Event *lastEventPtr;	/* Last pending event, or NULL if none. */
    Tcl_Event *markerEventPtr;	/* Last high-priority event in queue, or NULL
				 * if none. */
    Tcl_Size eventCount;		/* Number of entries, but refer to comments in
				 * Tcl_ServiceEvent(). */
    Tcl_Mutex queueMutex;	/* Mutex to protect access to the previous
				 * four fields. */
    int serviceMode;		/* One of TCL_SERVICE_NONE or
				 * TCL_SERVICE_ALL. */
    int blockTimeSet;		/* 0 means there is no maximum block time:
				 * block forever. */
    Tcl_Time blockTime;		/* If blockTimeSet is 1, gives the maximum
				 * elapsed time for the next block. */
    int inTraversal;		/* 1 if Tcl_SetMaxBlockTime is being called
				 * during an event source traversal. */
    int initialized;		/* 1 if notifier has been initialized. */
    EventSource *firstEventSourcePtr;
				/* Pointer to first event source in list of
				 * event sources for this thread. */
    Tcl_ThreadId threadId;	/* Thread that owns this notifier instance. */
    void *clientData;	/* Opaque handle for platform specific
				 * notifier. */

    struct ThreadSpecificData *nextPtr;
				/* Next notifier in global list of notifiers.
				 * Access is controlled by the listLock global
				 * mutex. */
} ThreadSpecificData;

static Tcl_ThreadDataKey dataKey;

    for (evPtr = tsdPtr->firstEventPtr; evPtr != NULL; ) {
	hold = evPtr;
	evPtr = evPtr->nextPtr;
	Tcl_Free(hold);
    }
    tsdPtr->firstEventPtr = NULL;
    tsdPtr->lastEventPtr = NULL;
    tsdPtr->eventCount = 0;
    Tcl_MutexUnlock(&(tsdPtr->queueMutex));

    Tcl_MutexLock(&listLock);

    Tcl_FinalizeNotifier(tsdPtr->clientData);
    Tcl_MutexFinalize(&(tsdPtr->queueMutex));
    for (prevPtrPtr = &firstNotifierPtr; *prevPtrPtr != NULL;

				 * must have been allocated the caller with
				 * malloc (Tcl_Alloc), and it becomes the
				 * property of the event queue. It will be
				 * freed after the event has been handled. */
    int position) /* One of TCL_QUEUE_TAIL, TCL_QUEUE_HEAD, TCL_QUEUE_MARK,
				 * possibly combined with TCL_QUEUE_ALERT_IF_EMPTY */
{
    int wasEmpty = 0;



    Tcl_MutexLock(&(tsdPtr->queueMutex));
    if ((position & 3) == TCL_QUEUE_TAIL) {
	/*
	 * Append the event on the end of the queue.
	 */

	evPtr->nextPtr = NULL;
	if (tsdPtr->firstEventPtr == NULL) {

	    tsdPtr->markerEventPtr->nextPtr = evPtr;
	}
	tsdPtr->markerEventPtr = evPtr;
	if (evPtr->nextPtr == NULL) {
	    tsdPtr->lastEventPtr = evPtr;
	}
    }
    if (position & TCL_QUEUE_ALERT_IF_EMPTY) {
	wasEmpty = (tsdPtr->eventCount <= 0);
    }
    tsdPtr->eventCount++;
    Tcl_MutexUnlock(&(tsdPtr->queueMutex));
    return wasEmpty;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_DeleteEvents --
 *

	    /*
	     * Delete the event data structure.
	     */

	    hold = evPtr;
	    evPtr = evPtr->nextPtr;
	    Tcl_Free(hold);
	    tsdPtr->eventCount--;
	} else {
	    /*
	     * Event is to be retained.
	     */

	    prevPtr = evPtr;
	    evPtr = evPtr->nextPtr;

				 * TCL_FILE_EVENTS, TCL_TIMER_EVENTS, or other
				 * flags defined elsewhere. Events not
				 * matching this will be skipped for
				 * processing later. */
{
    Tcl_Event *evPtr, *prevPtr;
    Tcl_EventProc *proc;
    Tcl_Size eventCount;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
    int result;

    /*
     * Asynchronous event handlers are considered to be the highest priority
     * events, and so must be invoked before we process events on the event
     * queue.
     */

	evPtr->proc = NULL;

	/*
	 * Release the lock before calling the event function. This allows
	 * other threads to post events if we enter a recursive event loop in
	 * this thread. Note that we are making the assumption that if the
	 * proc returns 0, the event is still in the list.
	 *
	 * The eventCount is remembered and set to zero that the next
	 * level of Tcl_ServiceEvent() gets an empty condition for the
	 * Tcl_ThreadQueueEvent() to perform optional wakeups.
	 * On exit of the next level, the eventCount is readjusted.
	 */

	eventCount = tsdPtr->eventCount;
	tsdPtr->eventCount = 0;
	Tcl_MutexUnlock(&(tsdPtr->queueMutex));
	result = proc(evPtr, flags);
	Tcl_MutexLock(&(tsdPtr->queueMutex));
	tsdPtr->eventCount += eventCount;

	if (result) {
	    /*
	     * The event was processed, so remove it from the queue.
	     */

	    if (tsdPtr->firstEventPtr == evPtr) {

		    }
		} else {
		    evPtr = NULL;
		}
	    }
	    if (evPtr) {
		Tcl_Free(evPtr);
		tsdPtr->eventCount--;
	    }
	    Tcl_MutexUnlock(&(tsdPtr->queueMutex));
	    return 1;
	} else {
	    /*
	     * The event wasn't actually handled, so we have to restore the
	     * proc field to allow the event to be attempted again.