/**
* If the current item in the event target chain has an event listener
* manager, this method calls nsEventListenerManager::HandleEvent().
*/
void HandleEvent(nsEventChainPostVisitor& aVisitor,
ELMCreationDetector& aCd)
{
if (WantsWillHandleEvent()) {
mTarget->WillHandleEvent(aVisitor);
}
if (aVisitor.mEvent->mFlags.mPropagationStopped) {
return;
}
if (!mManager) {
if (!MayHaveListenerManager() && !aCd.MayHaveNewListenerManager()) {
return;
}
mManager = mTarget->GetExistingListenerManager();
}
if (mManager) {
NS_ASSERTION(aVisitor.mEvent->currentTarget == nullptr,
"CurrentTarget should be null!");
mManager->HandleEvent(aVisitor.mPresContext, aVisitor.mEvent,
&aVisitor.mDOMEvent,
CurrentTarget(),
&aVisitor.mEventStatus);
NS_ASSERTION(aVisitor.mEvent->currentTarget == nullptr,
"CurrentTarget should be null!");
}
}
/**
* If the current item in the event target chain has an event listener
* manager, this method calls nsEventListenerManager::HandleEvent().
*/
nsresult HandleEvent(nsEventChainPostVisitor& aVisitor,
ELMCreationDetector& aCd,
nsCxPusher* aPusher)
{
if (WantsWillHandleEvent()) {
mTarget->WillHandleEvent(aVisitor);
}
if (aVisitor.mEvent->mFlags.mPropagationStopped) {
return NS_OK;
}
if (!mManager) {
if (!MayHaveListenerManager() && !aCd.MayHaveNewListenerManager()) {
return NS_OK;
}
mManager =
static_cast<nsEventListenerManager*>(mTarget->GetListenerManager(false));
}
if (mManager) {
NS_ASSERTION(aVisitor.mEvent->currentTarget == nullptr,
"CurrentTarget should be null!");
mManager->HandleEvent(aVisitor.mPresContext, aVisitor.mEvent,
&aVisitor.mDOMEvent,
CurrentTarget(),
&aVisitor.mEventStatus,
aPusher);
NS_ASSERTION(aVisitor.mEvent->currentTarget == nullptr,
"CurrentTarget should be null!");
}
return NS_OK;
}
/* static */ nsresult
nsEventDispatcher::Dispatch(nsISupports* aTarget,
nsPresContext* aPresContext,
WidgetEvent* aEvent,
nsIDOMEvent* aDOMEvent,
nsEventStatus* aEventStatus,
nsDispatchingCallback* aCallback,
nsCOMArray<EventTarget>* aTargets)
{
PROFILER_LABEL("nsEventDispatcher", "Dispatch");
NS_ASSERTION(aEvent, "Trying to dispatch without WidgetEvent!");
NS_ENSURE_TRUE(!aEvent->mFlags.mIsBeingDispatched,
NS_ERROR_DOM_INVALID_STATE_ERR);
NS_ASSERTION(!aTargets || !aEvent->message, "Wrong parameters!");
// If we're dispatching an already created DOMEvent object, make
// sure it is initialized!
// If aTargets is non-null, the event isn't going to be dispatched.
NS_ENSURE_TRUE(aEvent->message || !aDOMEvent || aTargets,
NS_ERROR_DOM_INVALID_STATE_ERR);
nsCOMPtr<EventTarget> target = do_QueryInterface(aTarget);
bool retargeted = false;
if (aEvent->mFlags.mRetargetToNonNativeAnonymous) {
nsCOMPtr<nsIContent> content = do_QueryInterface(target);
if (content && content->IsInNativeAnonymousSubtree()) {
nsCOMPtr<EventTarget> newTarget =
do_QueryInterface(content->FindFirstNonChromeOnlyAccessContent());
NS_ENSURE_STATE(newTarget);
aEvent->originalTarget = target;
target = newTarget;
retargeted = true;
}
}
if (aEvent->mFlags.mOnlyChromeDispatch) {
nsCOMPtr<nsINode> node = do_QueryInterface(aTarget);
if (!node) {
nsCOMPtr<nsPIDOMWindow> win = do_QueryInterface(aTarget);
if (win) {
node = win->GetExtantDoc();
}
}
NS_ENSURE_STATE(node);
nsIDocument* doc = node->OwnerDoc();
if (!nsContentUtils::IsChromeDoc(doc)) {
nsPIDOMWindow* win = doc ? doc->GetInnerWindow() : nullptr;
// If we can't dispatch the event to chrome, do nothing.
EventTarget* piTarget = win ? win->GetParentTarget() : nullptr;
NS_ENSURE_TRUE(piTarget, NS_OK);
// Set the target to be the original dispatch target,
aEvent->target = target;
// but use chrome event handler or TabChildGlobal for event target chain.
target = piTarget;
}
}
#ifdef DEBUG
if (!nsContentUtils::IsSafeToRunScript()) {
nsresult rv = NS_ERROR_FAILURE;
if (target->GetContextForEventHandlers(&rv) ||
NS_FAILED(rv)) {
nsCOMPtr<nsINode> node = do_QueryInterface(target);
if (node && nsContentUtils::IsChromeDoc(node->OwnerDoc())) {
NS_WARNING("Fix the caller!");
} else {
NS_ERROR("This is unsafe! Fix the caller!");
}
}
}
if (aDOMEvent) {
WidgetEvent* innerEvent = aDOMEvent->GetInternalNSEvent();
NS_ASSERTION(innerEvent == aEvent,
"The inner event of aDOMEvent is not the same as aEvent!");
}
#endif
nsresult rv = NS_OK;
bool externalDOMEvent = !!(aDOMEvent);
// If we have a PresContext, make sure it doesn't die before
// event dispatching is finished.
nsRefPtr<nsPresContext> kungFuDeathGrip(aPresContext);
ELMCreationDetector cd;
nsTArray<nsEventTargetChainItem> chain;
if (cd.IsMainThread()) {
if (!sCachedMainThreadChain) {
sCachedMainThreadChain = new nsTArray<nsEventTargetChainItem>();
}
chain.SwapElements(*sCachedMainThreadChain);
chain.SetCapacity(128);
}
// Create the event target chain item for the event target.
nsEventTargetChainItem* targetEtci =
nsEventTargetChainItem::Create(chain, target->GetTargetForEventTargetChain());
MOZ_ASSERT(&chain[0] == targetEtci);
if (!targetEtci->IsValid()) {
nsEventTargetChainItem::DestroyLast(chain, targetEtci);
return NS_ERROR_FAILURE;
}
// Make sure that nsIDOMEvent::target and nsIDOMEvent::originalTarget
// point to the last item in the chain.
if (!aEvent->target) {
// Note, CurrentTarget() points always to the object returned by
// GetTargetForEventTargetChain().
aEvent->target = targetEtci->CurrentTarget();
} else {
// XXX But if the target is already set, use that. This is a hack
// for the 'load', 'beforeunload' and 'unload' events,
// which are dispatched to |window| but have document as their target.
//
// Make sure that the event target points to the right object.
aEvent->target = aEvent->target->GetTargetForEventTargetChain();
NS_ENSURE_STATE(aEvent->target);
}
if (retargeted) {
aEvent->originalTarget =
aEvent->originalTarget->GetTargetForEventTargetChain();
NS_ENSURE_STATE(aEvent->originalTarget);
}
else {
aEvent->originalTarget = aEvent->target;
}
nsCOMPtr<nsIContent> content = do_QueryInterface(aEvent->originalTarget);
bool isInAnon = (content && content->IsInAnonymousSubtree());
aEvent->mFlags.mIsBeingDispatched = true;
// Create visitor object and start event dispatching.
// PreHandleEvent for the original target.
nsEventStatus status = aEventStatus ? *aEventStatus : nsEventStatus_eIgnore;
nsEventChainPreVisitor preVisitor(aPresContext, aEvent, aDOMEvent, status,
isInAnon);
targetEtci->PreHandleEvent(preVisitor);
if (!preVisitor.mCanHandle && preVisitor.mAutomaticChromeDispatch && content) {
// Event target couldn't handle the event. Try to propagate to chrome.
nsEventTargetChainItem::DestroyLast(chain, targetEtci);
targetEtci = EventTargetChainItemForChromeTarget(chain, content);
NS_ENSURE_STATE(targetEtci);
MOZ_ASSERT(&chain[0] == targetEtci);
targetEtci->PreHandleEvent(preVisitor);
}
if (preVisitor.mCanHandle) {
// At least the original target can handle the event.
// Setting the retarget to the |target| simplifies retargeting code.
nsCOMPtr<EventTarget> t = do_QueryInterface(aEvent->target);
targetEtci->SetNewTarget(t);
nsEventTargetChainItem* topEtci = targetEtci;
targetEtci = nullptr;
while (preVisitor.mParentTarget) {
EventTarget* parentTarget = preVisitor.mParentTarget;
nsEventTargetChainItem* parentEtci =
nsEventTargetChainItem::Create(chain, preVisitor.mParentTarget, topEtci);
if (!parentEtci->IsValid()) {
nsEventTargetChainItem::DestroyLast(chain, parentEtci);
rv = NS_ERROR_FAILURE;
break;
}
// Item needs event retargetting.
if (preVisitor.mEventTargetAtParent) {
// Need to set the target of the event
// so that also the next retargeting works.
preVisitor.mEvent->target = preVisitor.mEventTargetAtParent;
parentEtci->SetNewTarget(preVisitor.mEventTargetAtParent);
}
parentEtci->PreHandleEvent(preVisitor);
if (preVisitor.mCanHandle) {
topEtci = parentEtci;
} else {
nsEventTargetChainItem::DestroyLast(chain, parentEtci);
parentEtci = nullptr;
if (preVisitor.mAutomaticChromeDispatch && content) {
// Even if the current target can't handle the event, try to
// propagate to chrome.
nsCOMPtr<nsINode> disabledTarget = do_QueryInterface(parentTarget);
if (disabledTarget) {
parentEtci = EventTargetChainItemForChromeTarget(chain,
disabledTarget,
topEtci);
if (parentEtci) {
parentEtci->PreHandleEvent(preVisitor);
if (preVisitor.mCanHandle) {
chain[0].SetNewTarget(parentTarget);
topEtci = parentEtci;
continue;
}
}
}
}
break;
}
}
if (NS_SUCCEEDED(rv)) {
if (aTargets) {
aTargets->Clear();
aTargets->SetCapacity(chain.Length());
for (uint32_t i = 0; i < chain.Length(); ++i) {
aTargets->AppendObject(chain[i].CurrentTarget()->GetTargetForDOMEvent());
}
} else {
// Event target chain is created. Handle the chain.
nsEventChainPostVisitor postVisitor(preVisitor);
nsEventTargetChainItem::HandleEventTargetChain(chain,
postVisitor,
aCallback,
cd);
preVisitor.mEventStatus = postVisitor.mEventStatus;
// If the DOM event was created during event flow.
if (!preVisitor.mDOMEvent && postVisitor.mDOMEvent) {
preVisitor.mDOMEvent = postVisitor.mDOMEvent;
}
}
}
}
// Note, nsEventTargetChainItem objects are deleted when the chain goes out of
// the scope.
aEvent->mFlags.mIsBeingDispatched = false;
aEvent->mFlags.mDispatchedAtLeastOnce = true;
if (!externalDOMEvent && preVisitor.mDOMEvent) {
// An nsDOMEvent was created while dispatching the event.
// Duplicate private data if someone holds a pointer to it.
nsrefcnt rc = 0;
NS_RELEASE2(preVisitor.mDOMEvent, rc);
if (preVisitor.mDOMEvent) {
preVisitor.mDOMEvent->DuplicatePrivateData();
}
}
if (aEventStatus) {
*aEventStatus = preVisitor.mEventStatus;
}
if (cd.IsMainThread() && chain.Capacity() == 128 && sCachedMainThreadChain) {
chain.ClearAndRetainStorage();
chain.SwapElements(*sCachedMainThreadChain);
}
return rv;
}
