gecko-dev/dom/base/GlobalTeardownObserver.h

88 строки
3.1 KiB
C++

/* -*- 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 DOM_BASE_GLOBALTEARDOWNOBSERVER_H_
#define DOM_BASE_GLOBALTEARDOWNOBSERVER_H_
#include "mozilla/Attributes.h"
#include "mozilla/dom/EventTarget.h"
#include "mozilla/RefPtr.h"
#include "nsCycleCollectionParticipant.h"
#include "nsID.h"
#include "nsIGlobalObject.h"
#include "nsIScriptGlobalObject.h"
#include "nsISupports.h"
#include "nsISupportsUtils.h"
#include "nsPIDOMWindow.h"
#define NS_GLOBALTEARDOWNOBSERVER_IID \
{ \
0xc31fddb9, 0xec49, 0x4f24, { \
0x90, 0x16, 0xb5, 0x2b, 0x26, 0x6c, 0xb6, 0x29 \
} \
}
namespace mozilla {
class GlobalTeardownObserver
: public nsISupports,
public LinkedListElement<GlobalTeardownObserver> {
public:
NS_DECLARE_STATIC_IID_ACCESSOR(NS_GLOBALTEARDOWNOBSERVER_IID)
GlobalTeardownObserver();
explicit GlobalTeardownObserver(nsIGlobalObject* aGlobalObject,
bool aHasOrHasHadOwnerWindow = false);
nsPIDOMWindowInner* GetOwner() const { return mOwnerWindow; }
nsIGlobalObject* GetOwnerGlobal() const { return mParentObject; }
bool HasOrHasHadOwner() { return mHasOrHasHadOwnerWindow; }
void GetParentObject(nsIScriptGlobalObject** aParentObject) {
if (mParentObject) {
CallQueryInterface(mParentObject, aParentObject);
} else {
*aParentObject = nullptr;
}
}
virtual void DisconnectFromOwner();
// 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;
protected:
virtual ~GlobalTeardownObserver();
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 = nullptr;
// 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 = nullptr;
bool mHasOrHasHadOwnerWindow = false;
};
NS_DEFINE_STATIC_IID_ACCESSOR(GlobalTeardownObserver,
NS_GLOBALTEARDOWNOBSERVER_IID)
} // namespace mozilla
#endif