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/* -*- 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
/*
* nsStubMutationObserver is an implementation of the nsIMutationObserver
* interface (except for the methods on nsISupports) that is intended to be
* used as a base class within the content/layout library. All methods do
* nothing.
*/
#include "nsStubMutationObserver.h"
#include "mozilla/RefCountType.h"
#include "nsISupports.h"
#include "nsINode.h"
/******************************************************************************
* nsStubMutationObserver
*****************************************************************************/
NS_IMPL_NSIMUTATIONOBSERVER_CORE_STUB(nsStubMutationObserver)
NS_IMPL_NSIMUTATIONOBSERVER_CONTENT(nsStubMutationObserver)
/******************************************************************************
* MutationObserverWrapper
*****************************************************************************/
/**
* @brief Wrapper class for a mutation observer that observes multiple nodes.
*
* This wrapper implements all methods of the nsIMutationObserver interface
* and forwards all calls to its owner, which is an instance of
* nsMultiMutationObserver.
*
* This class holds a reference to the owner and AddRefs/Releases its owner
* as well to ensure lifetime.
*/
class MutationObserverWrapper final : public nsIMutationObserver {
public:
NS_DECL_ISUPPORTS
explicit MutationObserverWrapper(nsMultiMutationObserver* aOwner)
: mOwner(aOwner) {}
void CharacterDataWillChange(nsIContent* aContent,
const CharacterDataChangeInfo& aInfo) override {
MOZ_ASSERT(mOwner);
mOwner->CharacterDataWillChange(aContent, aInfo);
}
void CharacterDataChanged(nsIContent* aContent,
const CharacterDataChangeInfo& aInfo) override {
MOZ_ASSERT(mOwner);
mOwner->CharacterDataChanged(aContent, aInfo);
}
void AttributeWillChange(mozilla::dom::Element* aElement,
int32_t aNameSpaceID, nsAtom* aAttribute,
int32_t aModType) override {
MOZ_ASSERT(mOwner);
mOwner->AttributeWillChange(aElement, aNameSpaceID, aAttribute, aModType);
}
void AttributeChanged(mozilla::dom::Element* aElement, int32_t aNameSpaceID,
nsAtom* aAttribute, int32_t aModType,
const nsAttrValue* aOldValue) override {
MOZ_ASSERT(mOwner);
mOwner->AttributeChanged(aElement, aNameSpaceID, aAttribute, aModType,
aOldValue);
}
void AttributeSetToCurrentValue(mozilla::dom::Element* aElement,
int32_t aNameSpaceID,
nsAtom* aAttribute) override {
MOZ_ASSERT(mOwner);
mOwner->AttributeSetToCurrentValue(aElement, aNameSpaceID, aAttribute);
}
void ContentAppended(nsIContent* aFirstNewContent) override {
MOZ_ASSERT(mOwner);
mOwner->ContentAppended(aFirstNewContent);
}
void ContentInserted(nsIContent* aChild) override {
MOZ_ASSERT(mOwner);
mOwner->ContentInserted(aChild);
}
void ContentRemoved(nsIContent* aChild,
nsIContent* aPreviousSibling) override {
MOZ_ASSERT(mOwner);
mOwner->ContentRemoved(aChild, aPreviousSibling);
}
void NodeWillBeDestroyed(nsINode* aNode) override {
MOZ_ASSERT(mOwner);
AddRefWrapper();
RefPtr<nsMultiMutationObserver> owner = mOwner;
owner->NodeWillBeDestroyed(aNode);
owner->RemoveMutationObserverFromNode(aNode);
mOwner = nullptr;
ReleaseWrapper();
}
void ParentChainChanged(nsIContent* aContent) override {
MOZ_ASSERT(mOwner);
mOwner->ParentChainChanged(aContent);
}
void ARIAAttributeDefaultWillChange(mozilla::dom::Element* aElement,
nsAtom* aAttribute,
int32_t aModType) override {
MOZ_ASSERT(mOwner);
mOwner->ARIAAttributeDefaultWillChange(aElement, aAttribute, aModType);
}
void ARIAAttributeDefaultChanged(mozilla::dom::Element* aElement,
nsAtom* aAttribute,
int32_t aModType) override {
MOZ_ASSERT(mOwner);
mOwner->ARIAAttributeDefaultChanged(aElement, aAttribute, aModType);
}
MozExternalRefCountType AddRefWrapper() {
nsrefcnt count = ++mRefCnt;
NS_LOG_ADDREF(this, count, "MutationObserverWrapper", sizeof(*this));
return count;
}
MozExternalRefCountType ReleaseWrapper() {
--mRefCnt;
NS_LOG_RELEASE(this, mRefCnt, "MutationObserverWrapper");
if (mRefCnt == 0) {
mRefCnt = 1;
delete this;
return MozExternalRefCountType(0);
}
return mRefCnt;
}
private:
~MutationObserverWrapper() = default;
nsMultiMutationObserver* mOwner{nullptr};
};
NS_IMPL_QUERY_INTERFACE(MutationObserverWrapper, nsIMutationObserver);
MozExternalRefCountType MutationObserverWrapper::AddRef() {
MOZ_ASSERT(mOwner);
AddRefWrapper();
mOwner->AddRef();
return mRefCnt;
}
MozExternalRefCountType MutationObserverWrapper::Release() {
MOZ_ASSERT(mOwner);
mOwner->Release();
return ReleaseWrapper();
}
/******************************************************************************
* nsMultiMutationObserver
*****************************************************************************/
void nsMultiMutationObserver::AddMutationObserverToNode(nsINode* aNode) {
if (!aNode) {
return;
}
if (mWrapperForNode.Contains(aNode)) {
return;
}
auto* newWrapper = new MutationObserverWrapper{this};
newWrapper->AddRefWrapper();
mWrapperForNode.InsertOrUpdate(aNode, newWrapper);
aNode->AddMutationObserver(newWrapper);
}
void nsMultiMutationObserver::RemoveMutationObserverFromNode(nsINode* aNode) {
if (!aNode) {
return;
}
if (auto obs = mWrapperForNode.MaybeGet(aNode); obs.isSome()) {
aNode->RemoveMutationObserver(*obs);
mWrapperForNode.Remove(aNode);
(*obs)->ReleaseWrapper();
}
}
bool nsMultiMutationObserver::ContainsNode(const nsINode* aNode) const {
return mWrapperForNode.Contains(const_cast<nsINode*>(aNode));
}
/******************************************************************************
* nsStubMultiMutationObserver
*****************************************************************************/
NS_IMPL_NSIMUTATIONOBSERVER_CORE_STUB(nsStubMultiMutationObserver)
NS_IMPL_NSIMUTATIONOBSERVER_CONTENT(nsStubMultiMutationObserver)