dom/events/EventListenerManager.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_EventListenerManager_h_
   8 #define mozilla_EventListenerManager_h_
   9
  10 #include "mozilla/BasicEvents.h"
  11 #include "mozilla/JSEventHandler.h"
  12 #include "mozilla/MemoryReporting.h"
  13 #include "mozilla/dom/AbortFollower.h"
  14 #include "mozilla/dom/EventListenerBinding.h"
  15 #include "nsCOMPtr.h"
  16 #include "nsCycleCollectionParticipant.h"
  17 #include "nsGkAtoms.h"
  18 #include "nsIDOMEventListener.h"
  19 #include "nsTArray.h"
  20 #include "nsTObserverArray.h"
  21
  22 class nsIEventListenerInfo;
  23 class nsPIDOMWindowInner;
  24 class JSTracer;
  25
  26 struct EventTypeData;
  27
  28 namespace mozilla {
  29
  30 class ELMCreationDetector;
  31 class EventListenerManager;
  32 class ListenerSignalFollower;
  33
  34 namespace dom {
  35 class Event;
  36 class EventTarget;
  37 class Element;
  38 }  // namespace dom
  39
  40 using EventListenerHolder =
  41     dom::CallbackObjectHolder<dom::EventListener, nsIDOMEventListener>;
  42
  43 struct EventListenerFlags {
  44   friend class EventListenerManager;
  45
  46  private:
  47   // If mListenerIsJSListener is true, the listener is implemented by JS.
  48   // Otherwise, it's implemented by native code or JS but it's wrapped.
  49   bool mListenerIsJSListener : 1;
  50
  51  public:
  52   // If mCapture is true, it means the listener captures the event.  Otherwise,
  53   // it's listening at bubbling phase.
  54   bool mCapture : 1;
  55   // If mInSystemGroup is true, the listener is listening to the events in the
  56   // system group.
  57   bool mInSystemGroup : 1;
  58   // If mAllowUntrustedEvents is true, the listener is listening to the
  59   // untrusted events too.
  60   bool mAllowUntrustedEvents : 1;
  61   // If mPassive is true, the listener will not be calling preventDefault on the
  62   // event. (If it does call preventDefault, we should ignore it).
  63   bool mPassive : 1;
  64   // If mOnce is true, the listener will be removed from the manager before it
  65   // is invoked, so that it would only be invoked once.
  66   bool mOnce : 1;
  67
  68   EventListenerFlags()
  69       : mListenerIsJSListener(false),
  70         mCapture(false),
  71         mInSystemGroup(false),
  72         mAllowUntrustedEvents(false),
  73         mPassive(false),
  74         mOnce(false) {}
  75
  76   bool EqualsForAddition(const EventListenerFlags& aOther) const {
  77     return (mCapture == aOther.mCapture &&
  78             mInSystemGroup == aOther.mInSystemGroup &&
  79             mListenerIsJSListener == aOther.mListenerIsJSListener &&
  80             mAllowUntrustedEvents == aOther.mAllowUntrustedEvents);
  81     // Don't compare mPassive or mOnce
  82   }
  83
  84   bool EqualsForRemoval(const EventListenerFlags& aOther) const {
  85     return (mCapture == aOther.mCapture &&
  86             mInSystemGroup == aOther.mInSystemGroup &&
  87             mListenerIsJSListener == aOther.mListenerIsJSListener);
  88     // Don't compare mAllowUntrustedEvents, mPassive, or mOnce
  89   }
  90 };
  91
  92 inline EventListenerFlags TrustedEventsAtBubble() {
  93   EventListenerFlags flags;
  94   return flags;
  95 }
  96
  97 inline EventListenerFlags TrustedEventsAtCapture() {
  98   EventListenerFlags flags;
  99   flags.mCapture = true;
 100   return flags;
 101 }
 102
 103 inline EventListenerFlags AllEventsAtBubble() {
 104   EventListenerFlags flags;
 105   flags.mAllowUntrustedEvents = true;
 106   return flags;
 107 }
 108
 109 inline EventListenerFlags AllEventsAtCapture() {
 110   EventListenerFlags flags;
 111   flags.mCapture = true;
 112   flags.mAllowUntrustedEvents = true;
 113   return flags;
 114 }
 115
 116 inline EventListenerFlags TrustedEventsAtSystemGroupBubble() {
 117   EventListenerFlags flags;
 118   flags.mInSystemGroup = true;
 119   return flags;
 120 }
 121
 122 inline EventListenerFlags TrustedEventsAtSystemGroupCapture() {
 123   EventListenerFlags flags;
 124   flags.mCapture = true;
 125   flags.mInSystemGroup = true;
 126   return flags;
 127 }
 128
 129 inline EventListenerFlags AllEventsAtSystemGroupBubble() {
 130   EventListenerFlags flags;
 131   flags.mInSystemGroup = true;
 132   flags.mAllowUntrustedEvents = true;
 133   return flags;
 134 }
 135
 136 inline EventListenerFlags AllEventsAtSystemGroupCapture() {
 137   EventListenerFlags flags;
 138   flags.mCapture = true;
 139   flags.mInSystemGroup = true;
 140   flags.mAllowUntrustedEvents = true;
 141   return flags;
 142 }
 143
 144 class EventListenerManagerBase {
 145  protected:
 146   EventListenerManagerBase();
 147
 148   void ClearNoListenersForEvents() {
 149     mNoListenerForEvents[0] = eVoidEvent;
 150     mNoListenerForEvents[1] = eVoidEvent;
 151     mNoListenerForEvents[2] = eVoidEvent;
 152   }
 153
 154   EventMessage mNoListenerForEvents[3];
 155   uint16_t mMayHavePaintEventListener : 1;
 156   uint16_t mMayHaveMutationListeners : 1;
 157   uint16_t mMayHaveCapturingListeners : 1;
 158   uint16_t mMayHaveSystemGroupListeners : 1;
 159   uint16_t mMayHaveTouchEventListener : 1;
 160   uint16_t mMayHaveMouseEnterLeaveEventListener : 1;
 161   uint16_t mMayHavePointerEnterLeaveEventListener : 1;
 162   uint16_t mMayHaveSelectionChangeEventListener : 1;
 163   uint16_t mMayHaveFormSelectEventListener : 1;
 164   uint16_t mMayHaveTransitionEventListener : 1;
 165   uint16_t mClearingListeners : 1;
 166   uint16_t mIsMainThreadELM : 1;
 167   uint16_t mMayHaveListenersForUntrustedEvents : 1;
 168   // 3 unused flags.
 169 };
 170
 171 /*
 172  * Event listener manager
 173  */
 174
 175 class EventListenerManager final : public EventListenerManagerBase {
 176   ~EventListenerManager();
 177
 178  public:
 179   struct Listener;
 180   class ListenerSignalFollower : public dom::AbortFollower {
 181    public:
 182     explicit ListenerSignalFollower(EventListenerManager* aListenerManager,
 183                                     Listener* aListener);
 184
 185     NS_DECL_CYCLE_COLLECTING_ISUPPORTS
 186     NS_DECL_CYCLE_COLLECTION_CLASS(ListenerSignalFollower)
 187
 188     void RunAbortAlgorithm() override;
 189
 190     void Disconnect() {
 191       mListenerManager = nullptr;
 192       mListener.Reset();
 193       Unfollow();
 194     }
 195
 196    protected:
 197     ~ListenerSignalFollower() = default;
 198
 199     EventListenerManager* mListenerManager;
 200     EventListenerHolder mListener;
 201     RefPtr<nsAtom> mTypeAtom;
 202     EventMessage mEventMessage;
 203     bool mAllEvents;
 204     EventListenerFlags mFlags;
 205   };
 206
 207   struct Listener {
 208     RefPtr<ListenerSignalFollower> mSignalFollower;
 209     EventListenerHolder mListener;
 210     RefPtr<nsAtom> mTypeAtom;
 211     EventMessage mEventMessage;
 212
 213     enum ListenerType : uint8_t {
 214       // No listener.
 215       eNoListener,
 216       // A generic C++ implementation of nsIDOMEventListener.
 217       eNativeListener,
 218       // An event handler attribute using JSEventHandler.
 219       eJSEventListener,
 220       // A scripted EventListener.
 221       eWebIDLListener,
 222     };
 223     ListenerType mListenerType;
 224
 225     bool mListenerIsHandler : 1;
 226     bool mHandlerIsString : 1;
 227     bool mAllEvents : 1;
 228     bool mEnabled : 1;
 229
 230     EventListenerFlags mFlags;
 231
 232     JSEventHandler* GetJSEventHandler() const {
 233       return (mListenerType == eJSEventListener)
 234                  ? static_cast<JSEventHandler*>(mListener.GetXPCOMCallback())
 235                  : nullptr;
 236     }
 237
 238     Listener()
 239         : mEventMessage(eVoidEvent),
 240           mListenerType(eNoListener),
 241           mListenerIsHandler(false),
 242           mHandlerIsString(false),
 243           mAllEvents(false),
 244           mEnabled(true) {}
 245
 246     Listener(Listener&& aOther)
 247         : mSignalFollower(std::move(aOther.mSignalFollower)),
 248           mListener(std::move(aOther.mListener)),
 249           mTypeAtom(std::move(aOther.mTypeAtom)),
 250           mEventMessage(aOther.mEventMessage),
 251           mListenerType(aOther.mListenerType),
 252           mListenerIsHandler(aOther.mListenerIsHandler),
 253           mHandlerIsString(aOther.mHandlerIsString),
 254           mAllEvents(aOther.mAllEvents),
 255           mEnabled(aOther.mEnabled) {
 256       aOther.mEventMessage = eVoidEvent;
 257       aOther.mListenerType = eNoListener;
 258       aOther.mListenerIsHandler = false;
 259       aOther.mHandlerIsString = false;
 260       aOther.mAllEvents = false;
 261       aOther.mEnabled = true;
 262     }
 263
 264     ~Listener() {
 265       if ((mListenerType == eJSEventListener) && mListener) {
 266         static_cast<JSEventHandler*>(mListener.GetXPCOMCallback())
 267             ->Disconnect();
 268       }
 269       if (mSignalFollower) {
 270         mSignalFollower->Disconnect();
 271       }
 272     }
 273
 274     MOZ_ALWAYS_INLINE bool MatchesEventMessage(
 275         const WidgetEvent* aEvent, EventMessage aEventMessage) const;
 276
 277     MOZ_ALWAYS_INLINE bool MatchesEventGroup(const WidgetEvent* aEvent) const {
 278       return mFlags.mInSystemGroup == aEvent->mFlags.mInSystemGroup;
 279     }
 280
 281     MOZ_ALWAYS_INLINE bool MatchesEventPhase(const WidgetEvent* aEvent) const {
 282       return ((mFlags.mCapture && aEvent->mFlags.mInCapturePhase) ||
 283               (!mFlags.mCapture && aEvent->mFlags.mInBubblingPhase));
 284     }
 285
 286     // Allow only trusted events, except when listener permits untrusted
 287     // events.
 288     MOZ_ALWAYS_INLINE bool AllowsEventTrustedness(
 289         const WidgetEvent* aEvent) const {
 290       return aEvent->IsTrusted() || mFlags.mAllowUntrustedEvents;
 291     }
 292   };
 293
 294   explicit EventListenerManager(dom::EventTarget* aTarget);
 295
 296   NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(EventListenerManager)
 297
 298   NS_DECL_CYCLE_COLLECTION_NATIVE_CLASS(EventListenerManager)
 299
 300   void AddEventListener(const nsAString& aType, nsIDOMEventListener* aListener,
 301                         bool aUseCapture, bool aWantsUntrusted) {
 302     AddEventListener(aType, EventListenerHolder(aListener), aUseCapture,
 303                      aWantsUntrusted);
 304   }
 305   void AddEventListener(const nsAString& aType, dom::EventListener* aListener,
 306                         const dom::AddEventListenerOptionsOrBoolean& aOptions,
 307                         bool aWantsUntrusted) {
 308     AddEventListener(aType, EventListenerHolder(aListener), aOptions,
 309                      aWantsUntrusted);
 310   }
 311   void RemoveEventListener(const nsAString& aType,
 312                            nsIDOMEventListener* aListener, bool aUseCapture) {
 313     RemoveEventListener(aType, EventListenerHolder(aListener), aUseCapture);
 314   }
 315   void RemoveEventListener(const nsAString& aType,
 316                            dom::EventListener* aListener,
 317                            const dom::EventListenerOptionsOrBoolean& aOptions) {
 318     RemoveEventListener(aType, EventListenerHolder(aListener), aOptions);
 319   }
 320
 321   void AddListenerForAllEvents(dom::EventListener* aListener, bool aUseCapture,
 322                                bool aWantsUntrusted, bool aSystemEventGroup);
 323   void RemoveListenerForAllEvents(dom::EventListener* aListener,
 324                                   bool aUseCapture, bool aSystemEventGroup);
 325
 326   /**
 327    * Sets events listeners of all types.
 328    * @param an event listener
 329    */
 330   void AddEventListenerByType(nsIDOMEventListener* aListener,
 331                               const nsAString& type,
 332                               const EventListenerFlags& aFlags) {
 333     AddEventListenerByType(EventListenerHolder(aListener), type, aFlags);
 334   }
 335   void AddEventListenerByType(dom::EventListener* aListener,
 336                               const nsAString& type,
 337                               const EventListenerFlags& aFlags) {
 338     AddEventListenerByType(EventListenerHolder(aListener), type, aFlags);
 339   }
 340   void AddEventListenerByType(
 341       EventListenerHolder aListener, const nsAString& type,
 342       const EventListenerFlags& aFlags,
 343       const dom::Optional<bool>& aPassive = dom::Optional<bool>(),
 344       dom::AbortSignal* aSignal = nullptr);
 345   void RemoveEventListenerByType(nsIDOMEventListener* aListener,
 346                                  const nsAString& type,
 347                                  const EventListenerFlags& aFlags) {
 348     RemoveEventListenerByType(EventListenerHolder(aListener), type, aFlags);
 349   }
 350   void RemoveEventListenerByType(dom::EventListener* aListener,
 351                                  const nsAString& type,
 352                                  const EventListenerFlags& aFlags) {
 353     RemoveEventListenerByType(EventListenerHolder(aListener), type, aFlags);
 354   }
 355   void RemoveEventListenerByType(EventListenerHolder aListener,
 356                                  const nsAString& type,
 357                                  const EventListenerFlags& aFlags);
 358
 359   /**
 360    * Sets the current "inline" event listener for aName to be a
 361    * function compiled from aFunc if !aDeferCompilation.  If
 362    * aDeferCompilation, then we assume that we can get the string from
 363    * mTarget later and compile lazily.
 364    *
 365    * aElement, if not null, is the element the string is associated with.
 366    */
 367   // XXXbz does that play correctly with nodes being adopted across
 368   // documents?  Need to double-check the spec here.
 369   nsresult SetEventHandler(nsAtom* aName, const nsAString& aFunc,
 370                            bool aDeferCompilation, bool aPermitUntrustedEvents,
 371                            dom::Element* aElement);
 372   /**
 373    * Remove the current "inline" event listener for aName.
 374    */
 375   void RemoveEventHandler(nsAtom* aName);
 376
 377   // We only get called from the event dispatch code, which knows to be careful
 378   // with what it's doing.  We could annotate ourselves as MOZ_CAN_RUN_SCRIPT,
 379   // but then the event dispatch code would need a ton of MOZ_KnownLive for
 380   // things that come from slightly complicated stack-lifetime data structures.
 381   MOZ_CAN_RUN_SCRIPT_BOUNDARY
 382   void HandleEvent(nsPresContext* aPresContext, WidgetEvent* aEvent,
 383                    dom::Event** aDOMEvent, dom::EventTarget* aCurrentTarget,
 384                    nsEventStatus* aEventStatus, bool aItemInShadowTree) {
 385     if (!mMayHaveCapturingListeners && !aEvent->mFlags.mInBubblingPhase) {
 386       return;
 387     }
 388
 389     if (!mMayHaveSystemGroupListeners && aEvent->mFlags.mInSystemGroup) {
 390       return;
 391     }
 392
 393     if (!aEvent->IsTrusted() && !mMayHaveListenersForUntrustedEvents) {
 394       return;
 395     }
 396
 397     // Check if we already know that there is no event listener for the event.
 398     if (aEvent->mMessage == eUnidentifiedEvent) {
 399       if (mNoListenerForEventAtom == aEvent->mSpecifiedEventType) {
 400         return;
 401       }
 402     } else if (mNoListenerForEvents[0] == aEvent->mMessage ||
 403                mNoListenerForEvents[1] == aEvent->mMessage ||
 404                mNoListenerForEvents[2] == aEvent->mMessage) {
 405       return;
 406     }
 407
 408     if (mListeners.IsEmpty() || aEvent->PropagationStopped()) {
 409       return;
 410     }
 411
 412     HandleEventInternal(aPresContext, aEvent, aDOMEvent, aCurrentTarget,
 413                         aEventStatus, aItemInShadowTree);
 414   }
 415
 416   /**
 417    * Tells the event listener manager that its target (which owns it) is
 418    * no longer using it (and could go away).
 419    */
 420   void Disconnect();
 421
 422   /**
 423    * Allows us to quickly determine if we have mutation listeners registered.
 424    */
 425   bool HasMutationListeners();
 426
 427   /**
 428    * Allows us to quickly determine whether we have unload listeners registered.
 429    */
 430   bool HasUnloadListeners();
 431
 432   /**
 433    * Allows us to quickly determine whether we have beforeunload listeners
 434    * registered.
 435    */
 436   bool HasBeforeUnloadListeners();
 437
 438   /**
 439    * Returns the mutation bits depending on which mutation listeners are
 440    * registered to this listener manager.
 441    * @note If a listener is an nsIDOMMutationListener, all possible mutation
 442    *       event bits are returned. All bits are also returned if one of the
 443    *       event listeners is registered to handle DOMSubtreeModified events.
 444    */
 445   uint32_t MutationListenerBits();
 446
 447   /**
 448    * Returns true if there is at least one event listener for aEventName.
 449    */
 450   bool HasListenersFor(const nsAString& aEventName) const;
 451
 452   /**
 453    * Returns true if there is at least one event listener for aEventNameWithOn.
 454    * Note that aEventNameWithOn must start with "on"!
 455    */
 456   bool HasListenersFor(nsAtom* aEventNameWithOn) const;
 457
 458   /**
 459    * Similar to HasListenersFor, but ignores system group listeners.
 460    */
 461   bool HasNonSystemGroupListenersFor(nsAtom* aEventNameWithOn) const;
 462
 463   /**
 464    * Returns true if there is at least one event listener.
 465    */
 466   bool HasListeners() const;
 467
 468   /**
 469    * Sets aList to the list of nsIEventListenerInfo objects representing the
 470    * listeners managed by this listener manager.
 471    */
 472   nsresult GetListenerInfo(nsTArray<RefPtr<nsIEventListenerInfo>>& aList);
 473
 474   nsresult IsListenerEnabled(nsAString& aType, JSObject* aListener,
 475                              bool aCapturing, bool aAllowsUntrusted,
 476                              bool aInSystemEventGroup, bool aIsHandler,
 477                              bool* aEnabled);
 478
 479   nsresult SetListenerEnabled(nsAString& aType, JSObject* aListener,
 480                               bool aCapturing, bool aAllowsUntrusted,
 481                               bool aInSystemEventGroup, bool aIsHandler,
 482                               bool aEnabled);
 483
 484   uint32_t GetIdentifierForEvent(nsAtom* aEvent);
 485
 486   /**
 487    * Returns true if there may be a paint event listener registered,
 488    * false if there definitely isn't.
 489    */
 490   bool MayHavePaintEventListener() const { return mMayHavePaintEventListener; }
 491
 492   /**
 493    * Returns true if there may be a touch event listener registered,
 494    * false if there definitely isn't.
 495    */
 496   bool MayHaveTouchEventListener() const { return mMayHaveTouchEventListener; }
 497
 498   bool MayHaveMouseEnterLeaveEventListener() const {
 499     return mMayHaveMouseEnterLeaveEventListener;
 500   }
 501   bool MayHavePointerEnterLeaveEventListener() const {
 502     return mMayHavePointerEnterLeaveEventListener;
 503   }
 504   bool MayHaveSelectionChangeEventListener() const {
 505     return mMayHaveSelectionChangeEventListener;
 506   }
 507   bool MayHaveFormSelectEventListener() const {
 508     return mMayHaveFormSelectEventListener;
 509   }
 510   bool MayHaveTransitionEventListener() {
 511     return mMayHaveTransitionEventListener;
 512   }
 513
 514   size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const;
 515
 516   uint32_t ListenerCount() const { return mListeners.Length(); }
 517
 518   void MarkForCC();
 519
 520   void TraceListeners(JSTracer* aTrc);
 521
 522   dom::EventTarget* GetTarget() { return mTarget; }
 523
 524   bool HasNonSystemGroupListenersForUntrustedKeyEvents();
 525   bool HasNonPassiveNonSystemGroupListenersForUntrustedKeyEvents();
 526
 527   bool HasApzAwareListeners();
 528   bool IsApzAwareListener(Listener* aListener);
 529   bool IsApzAwareEvent(nsAtom* aEvent);
 530
 531   bool HasNonPassiveWheelListener();
 532
 533   /**
 534    * Remove all event listeners from the event target this EventListenerManager
 535    * is for.
 536    */
 537   void RemoveAllListeners();
 538
 539  protected:
 540   MOZ_CAN_RUN_SCRIPT
 541   void HandleEventInternal(nsPresContext* aPresContext, WidgetEvent* aEvent,
 542                            dom::Event** aDOMEvent,
 543                            dom::EventTarget* aCurrentTarget,
 544                            nsEventStatus* aEventStatus, bool aItemInShadowTree);
 545
 546   MOZ_CAN_RUN_SCRIPT
 547   nsresult HandleEventSubType(Listener* aListener, dom::Event* aDOMEvent,
 548                               dom::EventTarget* aCurrentTarget);
 549
 550   /**
 551    * If the given EventMessage has a legacy version that we support, then this
 552    * function returns that legacy version. Otherwise, this function simply
 553    * returns the passed-in EventMessage.
 554    */
 555   static EventMessage GetLegacyEventMessage(EventMessage aEventMessage);
 556
 557   /**
 558    * Get the event message for the given event name.
 559    */
 560   EventMessage GetEventMessage(nsAtom* aEventName) const;
 561
 562   /**
 563    * Get the event message and atom for the given event type.
 564    */
 565   EventMessage GetEventMessageAndAtomForListener(const nsAString& aType,
 566                                                  nsAtom** aAtom);
 567
 568   void ProcessApzAwareEventListenerAdd();
 569
 570   /**
 571    * Compile the "inline" event listener for aListener.  The
 572    * body of the listener can be provided in aBody; if this is null we
 573    * will look for it on mTarget.  If aBody is provided, aElement should be
 574    * as well; otherwise it will also be inferred from mTarget.
 575    */
 576   nsresult CompileEventHandlerInternal(Listener* aListener,
 577                                        const nsAString* aBody,
 578                                        dom::Element* aElement);
 579
 580   /**
 581    * Find the Listener for the "inline" event listener for aTypeAtom.
 582    */
 583   Listener* FindEventHandler(EventMessage aEventMessage, nsAtom* aTypeAtom);
 584
 585   /**
 586    * Set the "inline" event listener for aName to aHandler.  aHandler may be
 587    * have no actual handler set to indicate that we should lazily get and
 588    * compile the string for this listener, but in that case aContext and
 589    * aScopeGlobal must be non-null.  Otherwise, aContext and aScopeGlobal are
 590    * allowed to be null.
 591    */
 592   Listener* SetEventHandlerInternal(nsAtom* aName,
 593                                     const TypedEventHandler& aHandler,
 594                                     bool aPermitUntrustedEvents);
 595
 596   bool IsDeviceType(EventMessage aEventMessage);
 597   void EnableDevice(EventMessage aEventMessage);
 598   void DisableDevice(EventMessage aEventMessage);
 599
 600   bool HasListenersForInternal(nsAtom* aEventNameWithOn,
 601                                bool aIgnoreSystemGroup) const;
 602
 603   Listener* GetListenerFor(nsAString& aType, JSObject* aListener,
 604                            bool aCapturing, bool aAllowsUntrusted,
 605                            bool aInSystemEventGroup, bool aIsHandler);
 606
 607  public:
 608   /**
 609    * Set the "inline" event listener for aEventName to aHandler.  If
 610    * aHandler is null, this will actually remove the event listener
 611    */
 612   void SetEventHandler(nsAtom* aEventName, dom::EventHandlerNonNull* aHandler);
 613   void SetEventHandler(dom::OnErrorEventHandlerNonNull* aHandler);
 614   void SetEventHandler(dom::OnBeforeUnloadEventHandlerNonNull* aHandler);
 615
 616   /**
 617    * Get the value of the "inline" event listener for aEventName.
 618    * This may cause lazy compilation if the listener is uncompiled.
 619    *
 620    * Note: It's the caller's responsibility to make sure to call the right one
 621    * of these methods.  In particular, "onerror" events use
 622    * OnErrorEventHandlerNonNull for some event targets and EventHandlerNonNull
 623    * for others.
 624    */
 625   dom::EventHandlerNonNull* GetEventHandler(nsAtom* aEventName) {
 626     const TypedEventHandler* typedHandler = GetTypedEventHandler(aEventName);
 627     return typedHandler ? typedHandler->NormalEventHandler() : nullptr;
 628   }
 629
 630   dom::OnErrorEventHandlerNonNull* GetOnErrorEventHandler() {
 631     const TypedEventHandler* typedHandler =
 632         GetTypedEventHandler(nsGkAtoms::onerror);
 633     return typedHandler ? typedHandler->OnErrorEventHandler() : nullptr;
 634   }
 635
 636   dom::OnBeforeUnloadEventHandlerNonNull* GetOnBeforeUnloadEventHandler() {
 637     const TypedEventHandler* typedHandler =
 638         GetTypedEventHandler(nsGkAtoms::onbeforeunload);
 639     return typedHandler ? typedHandler->OnBeforeUnloadEventHandler() : nullptr;
 640   }
 641
 642  private:
 643   already_AddRefed<nsPIDOMWindowInner> WindowFromListener(
 644       Listener* aListener, bool aItemInShadowTree);
 645
 646  protected:
 647   /**
 648    * Helper method for implementing the various Get*EventHandler above.  Will
 649    * return null if we don't have an event handler for this event name.
 650    */
 651   const TypedEventHandler* GetTypedEventHandler(nsAtom* aEventName);
 652
 653   void AddEventListener(const nsAString& aType, EventListenerHolder aListener,
 654                         const dom::AddEventListenerOptionsOrBoolean& aOptions,
 655                         bool aWantsUntrusted);
 656   void AddEventListener(const nsAString& aType, EventListenerHolder aListener,
 657                         bool aUseCapture, bool aWantsUntrusted);
 658   void RemoveEventListener(const nsAString& aType,
 659                            EventListenerHolder aListener,
 660                            const dom::EventListenerOptionsOrBoolean& aOptions);
 661   void RemoveEventListener(const nsAString& aType,
 662                            EventListenerHolder aListener, bool aUseCapture);
 663
 664   void AddEventListenerInternal(EventListenerHolder aListener,
 665                                 EventMessage aEventMessage, nsAtom* aTypeAtom,
 666                                 const EventListenerFlags& aFlags,
 667                                 bool aHandler = false, bool aAllEvents = false,
 668                                 dom::AbortSignal* aSignal = nullptr);
 669   void RemoveEventListenerInternal(EventListenerHolder aListener,
 670                                    EventMessage aEventMessage,
 671                                    nsAtom* aUserType,
 672                                    const EventListenerFlags& aFlags,
 673                                    bool aAllEvents = false);
 674   void RemoveAllListenersSilently();
 675   void NotifyEventListenerRemoved(nsAtom* aUserType);
 676   const EventTypeData* GetTypeDataForIID(const nsIID& aIID);
 677   const EventTypeData* GetTypeDataForEventName(nsAtom* aName);
 678   nsPIDOMWindowInner* GetInnerWindowForTarget();
 679   already_AddRefed<nsPIDOMWindowInner> GetTargetAsInnerWindow() const;
 680
 681   bool ListenerCanHandle(const Listener* aListener, const WidgetEvent* aEvent,
 682                          EventMessage aEventMessage) const;
 683
 684   // BE AWARE, a lot of instances of EventListenerManager will be created.
 685   // Therefor, we need to keep this class compact.  When you add integer
 686   // members, please add them to EventListemerManagerBase and check the size
 687   // at build time.
 688
 689   already_AddRefed<nsIScriptGlobalObject> GetScriptGlobalAndDocument(
 690       mozilla::dom::Document** aDoc);
 691
 692   void MaybeMarkPassive(EventMessage aMessage, EventListenerFlags& aFlags);
 693
 694   nsAutoTObserverArray<Listener, 2> mListeners;
 695   dom::EventTarget* MOZ_NON_OWNING_REF mTarget;
 696   RefPtr<nsAtom> mNoListenerForEventAtom;
 697
 698   friend class ELMCreationDetector;
 699   static uint32_t sMainThreadCreatedCount;
 700 };
 701
 702 }  // namespace mozilla
 703
 704 #endif  // mozilla_EventListenerManager_h_