summaryrefslogtreecommitdiffstats
path: root/dom/events/DOMEventTargetHelper.h
blob: 3734fe0ef4f7e1b5c54f339a70acc329267d0e3c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
/* -*- 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/EventTarget.h"
#include "mozilla/GlobalTeardownObserver.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;
enum class CallerType : uint32_t;
}  // namespace dom

#define NS_DOMEVENTTARGETHELPER_IID                  \
  {                                                  \
    0xa28385c6, 0x9451, 0x4d7e, {                    \
      0xa3, 0xdd, 0xf4, 0xb6, 0x87, 0x2f, 0xa4, 0x76 \
    }                                                \
  }

class DOMEventTargetHelper : public dom::EventTarget,
                             public GlobalTeardownObserver {
 public:
  DOMEventTargetHelper();
  explicit DOMEventTargetHelper(nsPIDOMWindowInner* aWindow);
  explicit DOMEventTargetHelper(nsIGlobalObject* aGlobalObject);
  explicit DOMEventTargetHelper(DOMEventTargetHelper* aOther);

  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
  NS_DECL_CYCLE_COLLECTION_SKIPPABLE_WRAPPERCACHE_CLASS_AMBIGUOUS(
      DOMEventTargetHelper, dom::EventTarget)

  virtual EventListenerManager* GetExistingListenerManager() const override;
  virtual EventListenerManager* GetOrCreateListenerManager() override;

  bool ComputeDefaultWantsUntrusted(ErrorResult& aRv) override;

  using EventTarget::DispatchEvent;
  // TODO: Convert this to MOZ_CAN_RUN_SCRIPT (bug 1415230)
  MOZ_CAN_RUN_SCRIPT_BOUNDARY 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)

  nsIGlobalObject* GetOwnerGlobal() const override {
    return GlobalTeardownObserver::GetOwnerGlobal();
  }

  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());
  }

  // 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;

  void DisconnectFromOwner() override;
  using EventTarget::GetParentObject;

  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(nsAtom* aType);

  void IgnoreKeepAliveIfHasListenersFor(nsAtom* aType);

 private:
  nsTArray<RefPtr<nsAtom>> mKeepingAliveTypes;

  bool mIsKeptAlive = false;
};

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_