1 files changed, 198 insertions, 0 deletions
diff --git a/dom/events/DOMEventTargetHelper.h b/dom/events/DOMEventTargetHelper.h
new file mode 100644
index 0000000000..477e789525
--- /dev/null
+++ b/dom/events/DOMEventTargetHelper.h
@@ -0,0 +1,198 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_DOMEventTargetHelper_h_
+#define mozilla_DOMEventTargetHelper_h_
+
+#include "mozilla/Attributes.h"
+#include "mozilla/dom/BindingDeclarations.h"
+#include "mozilla/dom/EventTarget.h"
+#include "mozilla/LinkedList.h"
+#include "mozilla/RefPtr.h"
+#include "nsAtom.h"
+#include "nsCOMPtr.h"
+#include "nsCycleCollectionParticipant.h"
+#include "nsDebug.h"
+#include "nsGkAtoms.h"
+#include "nsID.h"
+#include "nsIGlobalObject.h"
+#include "nsIScriptGlobalObject.h"
+#include "nsISupports.h"
+#include "nsISupportsUtils.h"
+#include "nsPIDOMWindow.h"
+#include "nsStringFwd.h"
+#include "nsTArray.h"
+
+class nsCycleCollectionTraversalCallback;
+
+namespace mozilla {
+
+class ErrorResult;
+class EventChainPostVisitor;
+class EventChainPreVisitor;
+class EventListenerManager;
+
+namespace dom {
+class Document;
+class Event;
+}  // namespace dom
+
+#define NS_DOMEVENTTARGETHELPER_IID                  \
+  {                                                  \
+    0xa28385c6, 0x9451, 0x4d7e, {                    \
+      0xa3, 0xdd, 0xf4, 0xb6, 0x87, 0x2f, 0xa4, 0x76 \
+    }                                                \
+  }
+
+class DOMEventTargetHelper : public dom::EventTarget,
+                             public LinkedListElement<DOMEventTargetHelper> {
+ public:
+  DOMEventTargetHelper();
+  explicit DOMEventTargetHelper(nsPIDOMWindowInner* aWindow);
+  explicit DOMEventTargetHelper(nsIGlobalObject* aGlobalObject);
+  explicit DOMEventTargetHelper(DOMEventTargetHelper* aOther);
+
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_CYCLE_COLLECTION_SKIPPABLE_SCRIPT_HOLDER_CLASS(DOMEventTargetHelper)
+
+  virtual EventListenerManager* GetExistingListenerManager() const override;
+  virtual EventListenerManager* GetOrCreateListenerManager() override;
+
+  bool ComputeDefaultWantsUntrusted(ErrorResult& aRv) override;
+
+  using EventTarget::DispatchEvent;
+  bool DispatchEvent(dom::Event& aEvent, dom::CallerType aCallerType,
+                     ErrorResult& aRv) override;
+
+  void GetEventTargetParent(EventChainPreVisitor& aVisitor) override;
+
+  nsresult PostHandleEvent(EventChainPostVisitor& aVisitor) override;
+
+  NS_DECLARE_STATIC_IID_ACCESSOR(NS_DOMEVENTTARGETHELPER_IID)
+
+  void GetParentObject(nsIScriptGlobalObject** aParentObject) {
+    if (mParentObject) {
+      CallQueryInterface(mParentObject, aParentObject);
+    } else {
+      *aParentObject = nullptr;
+    }
+  }
+
+  static DOMEventTargetHelper* FromSupports(nsISupports* aSupports) {
+    dom::EventTarget* target = static_cast<dom::EventTarget*>(aSupports);
+#ifdef DEBUG
+    {
+      nsCOMPtr<dom::EventTarget> target_qi = do_QueryInterface(aSupports);
+
+      // If this assertion fires the QI implementation for the object in
+      // question doesn't use the EventTarget pointer as the
+      // nsISupports pointer. That must be fixed, or we'll crash...
+      NS_ASSERTION(target_qi == target, "Uh, fix QI!");
+    }
+#endif
+
+    return static_cast<DOMEventTargetHelper*>(target);
+  }
+
+  bool HasListenersFor(const nsAString& aType) const;
+
+  bool HasListenersFor(nsAtom* aTypeWithOn) const;
+
+  virtual nsPIDOMWindowOuter* GetOwnerGlobalForBindingsInternal() override {
+    return nsPIDOMWindowOuter::GetFromCurrentInner(GetOwner());
+  }
+
+  // A global permanently becomes invalid when DisconnectEventTargetObjects() is
+  // called.  Normally this means:
+  // - For the main thread, when nsGlobalWindowInner::FreeInnerObjects is
+  //   called.
+  // - For a worker thread, when clearing the main event queue.  (Which we do
+  //   slightly later than when the spec notionally calls for it to be done.)
+  //
+  // A global may also become temporarily invalid when:
+  // - For the main thread, if the window is no longer the WindowProxy's current
+  //   inner window due to being placed in the bfcache.
+  nsresult CheckCurrentGlobalCorrectness() const;
+
+  nsPIDOMWindowInner* GetOwner() const { return mOwnerWindow; }
+  // Like GetOwner, but only returns non-null if the window being returned is
+  // current (in the "current document" sense of the HTML spec).
+  nsPIDOMWindowInner* GetWindowIfCurrent() const;
+  // Returns the document associated with this event target, if that document is
+  // the current document of its browsing context.  Will return null otherwise.
+  mozilla::dom::Document* GetDocumentIfCurrent() const;
+
+  virtual void DisconnectFromOwner();
+  using EventTarget::GetParentObject;
+  nsIGlobalObject* GetOwnerGlobal() const final { return mParentObject; }
+  bool HasOrHasHadOwner() { return mHasOrHasHadOwnerWindow; }
+
+  virtual void EventListenerAdded(nsAtom* aType) override;
+
+  virtual void EventListenerRemoved(nsAtom* aType) override;
+
+  // Dispatch a trusted, non-cancellable and non-bubbling event to |this|.
+  nsresult DispatchTrustedEvent(const nsAString& aEventName);
+
+ protected:
+  virtual ~DOMEventTargetHelper();
+
+  nsresult WantsUntrusted(bool* aRetVal);
+
+  void MaybeUpdateKeepAlive();
+  void MaybeDontKeepAlive();
+
+  // If this method returns true your object is kept alive until it returns
+  // false. You can use this method instead using
+  // NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_BEGIN macro.
+  virtual bool IsCertainlyAliveForCC() const { return mIsKeptAlive; }
+
+  RefPtr<EventListenerManager> mListenerManager;
+  // Make |event| trusted and dispatch |aEvent| to |this|.
+  nsresult DispatchTrustedEvent(dom::Event* aEvent);
+
+  virtual void LastRelease() {}
+
+  void KeepAliveIfHasListenersFor(const nsAString& aType);
+  void KeepAliveIfHasListenersFor(nsAtom* aType);
+
+  void IgnoreKeepAliveIfHasListenersFor(const nsAString& aType);
+  void IgnoreKeepAliveIfHasListenersFor(nsAtom* aType);
+
+  void BindToOwner(nsIGlobalObject* aOwner);
+
+ private:
+  // The parent global object.  The global will clear this when
+  // it is destroyed by calling DisconnectFromOwner().
+  nsIGlobalObject* MOZ_NON_OWNING_REF mParentObject;
+  // mParentObject pre QI-ed and cached (inner window)
+  // (it is needed for off main thread access)
+  // It is obtained in BindToOwner and reset in DisconnectFromOwner.
+  nsPIDOMWindowInner* MOZ_NON_OWNING_REF mOwnerWindow;
+  bool mHasOrHasHadOwnerWindow;
+
+  struct {
+    nsTArray<nsString> mStrings;
+    nsTArray<RefPtr<nsAtom>> mAtoms;
+  } mKeepingAliveTypes;
+
+  bool mIsKeptAlive;
+};
+
+NS_DEFINE_STATIC_IID_ACCESSOR(DOMEventTargetHelper, NS_DOMEVENTTARGETHELPER_IID)
+
+}  // namespace mozilla
+
+// WebIDL event handlers
+#define IMPL_EVENT_HANDLER(_event)                                          \
+  inline mozilla::dom::EventHandlerNonNull* GetOn##_event() {               \
+    return GetEventHandler(nsGkAtoms::on##_event);                          \
+  }                                                                         \
+  inline void SetOn##_event(mozilla::dom::EventHandlerNonNull* aCallback) { \
+    SetEventHandler(nsGkAtoms::on##_event, aCallback);                      \
+  }
+
+#endif  // mozilla_DOMEventTargetHelper_h_