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Re: [Events] removeEventListener on EventListeners currently being processed

From: Michael B. Allen <mballen@erols.com>
Date: Sat, 18 Aug 2001 23:51:25 -0400
To: www-dom@w3.org
Message-ID: <20010818235125.A8135@nano.foo.net>
On Sat, Aug 18, 2001 at 08:03:26PM -0500, Curt Arnold wrote:
> > listener after it has been removed. I suspect I must collect the pointers
> > to the actull functions to be called for each listener and store that
> > in an array (i.e. pre-dereference the listener functions).
> 
> Actually, you should already have to collect the listeners since event
> listeners added while processing a dispatch to the same target should not
> see the event.

And it is so. Not too bad actually.

int
DOM_EventTarget_dispatchEvent(DOM_EventTarget *target, DOM_Event *evt)
{
   DOM_EventTarget **targets, *t;
   ListenerEntry *e;
   unsigned int tcount, i, j, lcount;

   if (target == NULL || evt == NULL) {
      DOM_Exception = DOM_NULL_POINTER_ERR;
      return 1;
   }

   if (evt->type == NULL || *evt->type == '\0') {
      DOM_EventException = DOM_UNSPECIFIED_EVENT_TYPE_ERR;
      return 1;
   }

   evt->target = target;                     /* post-initialization */
   evt->timeStamp = time(NULL);
   if (evt->timeStamp == (time_t)-1) {
      DOM_Exception = DOM_SYSTEM_ERR;
      return 1;
   }
   evt->sp = 0;
   evt->pd = 0;

   tcount = 0;                           /* count targets/ancestors */
   for (t = target->parentNode; t; t = t->parentNode) {
      tcount++;
   }
   if (tcount) {
      targets = malloc(sizeof *targets * tcount);
      if (targets == NULL) {
         DOM_Exception = DOM_NO_MEMORY_ERR;
         return 1;
      }
   }

   i = tcount;               /* save state of tree in targets array */
   for (t = target->parentNode; t; t = t->parentNode) {
      targets[--i] = t;
   }

   /* Trigger capturers
    */
   evt->eventPhase = DOM_EVENT_CAPTURING_PHASE;
   for (i = 0; i < tcount && evt->sp == 0; i++) {
      DOM_EventListener listeners[targets[i]->num_listeners];
                                                   /* use stack ok? */
      t = targets[i];
      lcount = 0;               /* copy relevant listener functions */
      for (j = 0; j < t->num_listeners; j++) {
         e = t->listeners[j];
         if (e->useCapture &&
                        DOM_String_cmp(e->type, evt->type) == 0) {
            listeners[lcount++] = e->listener;
         }
      }

      evt->currentTarget = t;
      while (lcount) {
         listeners[--lcount](evt);
      }
   }

   /* Trigger regular listeners
     */
   evt->eventPhase = DOM_EVENT_AT_TARGET;
   if (target->num_listeners && evt->sp == 0) {
      DOM_EventListener listeners[target->num_listeners];

      lcount = 0;
      for (j = 0; j < target->num_listeners; j++) {
         e = target->listeners[j];
         if (e->useCapture == 0 &&
                        DOM_String_cmp(e->type, evt->type) == 0) {
            listeners[lcount++] = e->listener;
         }
      }

      evt->currentTarget = target;
      while (lcount) {
         listeners[--lcount](evt);
      }
   }

   /* Trigger bubblers
     */
   evt->eventPhase = DOM_EVENT_BUBBLING_PHASE;
   i = tcount;
   while (i-- && evt->sp == 0) {
      DOM_EventListener listeners[targets[i]->num_listeners];

      t = targets[i];
      lcount = 0;
      for (j = 0; j < t->num_listeners; j++) {
         e = t->listeners[j];
         if (e->useCapture == 0 &&
                        DOM_String_cmp(e->type, evt->type) == 0) {
            listeners[lcount++] = e->listener;
         }
      }

      evt->currentTarget = t;
      while (lcount) {
         listeners[--lcount](evt);
      }
   }

   free(targets);
   return evt->pd;
}

-- 
Wow a memory-mapped fork bomb! Now what on earth did you expect? - lkml
Received on Saturday, 18 August 2001 23:45:04 GMT

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