Source code

Revision control

Copy as Markdown

Other Tools

/* -*- 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 */
#ifndef mozilla_dom_DocumentOrShadowRoot_h__
#define mozilla_dom_DocumentOrShadowRoot_h__
#include "mozilla/dom/NameSpaceConstants.h"
#include "mozilla/IdentifierMapEntry.h"
#include "mozilla/RelativeTo.h"
#include "mozilla/ReverseIterator.h"
#include "nsClassHashtable.h"
#include "nsContentListDeclarations.h"
#include "nsTArray.h"
#include "nsTHashSet.h"
#include "RadioGroupManager.h"
class nsContentList;
class nsCycleCollectionTraversalCallback;
class nsINode;
class nsINodeList;
class nsIRadioVisitor;
class nsWindowSizes;
namespace mozilla {
class ErrorResult;
class StyleSheet;
class ErrorResult;
namespace dom {
class Animation;
class Element;
class Document;
class DocumentOrShadowRoot;
class HTMLInputElement;
class StyleSheetList;
class ShadowRoot;
template <typename T>
class Sequence;
* A class meant to be shared by ShadowRoot and Document, that holds a list of
* stylesheets.
* TODO(emilio, bug 1418159): In the future this should hold most of the
* relevant style state, this should allow us to fix bug 548397.
class DocumentOrShadowRoot : public RadioGroupManager {
enum class Kind {
// These should always be non-null, but can't use a reference because
// dereferencing `this` on initializer lists is UB, apparently, see
explicit DocumentOrShadowRoot(Document*);
explicit DocumentOrShadowRoot(ShadowRoot*);
// Unusual argument naming is because of cycle collection macros.
static void Traverse(DocumentOrShadowRoot* tmp,
nsCycleCollectionTraversalCallback& cb);
static void Unlink(DocumentOrShadowRoot* tmp);
nsINode& AsNode() { return *mAsNode; }
const nsINode& AsNode() const { return *mAsNode; }
StyleSheet* SheetAt(size_t aIndex) const {
return mStyleSheets.SafeElementAt(aIndex);
size_t SheetCount() const { return mStyleSheets.Length(); }
const nsTArray<RefPtr<StyleSheet>>& AdoptedStyleSheets() const {
return mAdoptedStyleSheets;
* Returns an index for the sheet in relative style order.
* If there are non-applicable sheets, then this index may
* not match 1:1 with the sheet's actual index in the style set.
* Handles sheets from both mStyleSheets and mAdoptedStyleSheets
int32_t StyleOrderIndexOfSheet(const StyleSheet& aSheet) const;
StyleSheetList* StyleSheets();
void RemoveStyleSheet(StyleSheet&);
Element* GetElementById(const nsAString& aElementId);
* This method returns _all_ the elements in this scope which have id
* aElementId, if there are any. Otherwise it returns null.
* This is useful for stuff like QuerySelector optimization and such.
inline const nsTArray<Element*>* GetAllElementsForId(
const nsAString& aElementId) const;
already_AddRefed<nsContentList> GetElementsByTagName(
const nsAString& aTagName) {
return NS_GetContentList(&AsNode(), kNameSpaceID_Unknown, aTagName);
already_AddRefed<nsContentList> GetElementsByTagNameNS(
const nsAString& aNamespaceURI, const nsAString& aLocalName);
already_AddRefed<nsContentList> GetElementsByTagNameNS(
const nsAString& aNamespaceURI, const nsAString& aLocalName,
already_AddRefed<nsContentList> GetElementsByClassName(
const nsAString& aClasses);
Element* GetPointerLockElement();
Element* GetFullscreenElement() const;
Element* ElementFromPoint(float aX, float aY);
nsINode* NodeFromPoint(float aX, float aY);
void ElementsFromPoint(float aX, float aY, nsTArray<RefPtr<Element>>&);
void NodesFromPoint(float aX, float aY, nsTArray<RefPtr<nsINode>>&);
* Helper for elementFromPoint implementation that allows
* ignoring the scroll frame and/or avoiding layout flushes.
* @see nsIDOMWindowUtils::elementFromPoint
Element* ElementFromPointHelper(float aX, float aY,
bool aIgnoreRootScrollFrame,
bool aFlushLayout,
ViewportType aViewportType);
void NodesFromRect(float aX, float aY, float aTopSize, float aRightSize,
float aBottomSize, float aLeftSize,
bool aIgnoreRootScrollFrame, bool aFlushLayout,
bool aOnlyVisible, float aVisibleThreshold,
* This gets fired when the element that an id refers to changes.
* This fires at difficult times. It is generally not safe to do anything
* which could modify the DOM in any way. Use
* nsContentUtils::AddScriptRunner.
* @return true to keep the callback in the callback set, false
* to remove it.
typedef bool (*IDTargetObserver)(Element* aOldElement, Element* aNewelement,
void* aData);
* Add an IDTargetObserver for a specific ID. The IDTargetObserver
* will be fired whenever the content associated with the ID changes
* in the future. If aForImage is true, mozSetImageElement can override
* what content is associated with the ID. In that case the IDTargetObserver
* will be notified at those times when the result of LookupImageElement
* changes.
* At most one (aObserver, aData, aForImage) triple can be
* registered for each ID.
* @return the content currently associated with the ID.
Element* AddIDTargetObserver(nsAtom* aID, IDTargetObserver aObserver,
void* aData, bool aForImage);
* Remove the (aObserver, aData, aForImage) triple for a specific ID, if
* registered.
void RemoveIDTargetObserver(nsAtom* aID, IDTargetObserver aObserver,
void* aData, bool aForImage);
* Lookup an image element using its associated ID, which is usually provided
* by |-moz-element()|. Similar to GetElementById, with the difference that
* elements set using mozSetImageElement have higher priority.
* @param aId the ID associated the element we want to lookup
* @return the element associated with |aId|
Element* LookupImageElement(const nsAString& aElementId);
* Check that aId is not empty and log a message to the console
* service if it is.
* @returns true if aId looks correct, false otherwise.
inline bool CheckGetElementByIdArg(const nsAString& aId) {
if (aId.IsEmpty()) {
return false;
return true;
void ReportEmptyGetElementByIdArg();
// Web Animations
void GetAnimations(nsTArray<RefPtr<Animation>>& aAnimations);
nsIContent* Retarget(nsIContent* aContent) const;
void OnSetAdoptedStyleSheets(StyleSheet&, uint32_t aIndex, ErrorResult&);
void OnDeleteAdoptedStyleSheets(StyleSheet&, uint32_t aIndex, ErrorResult&);
// This is needed because ServoStyleSet / ServoAuthorData don't deal with
// duplicate stylesheets (and it's unclear we'd want to support that as it'd
// be a bunch of duplicate work), while adopted stylesheets do need to deal
// with them.
template <typename Callback>
void EnumerateUniqueAdoptedStyleSheetsBackToFront(Callback aCallback) {
StyleSheetSet set(mAdoptedStyleSheets.Length());
for (StyleSheet* sheet : Reversed(mAdoptedStyleSheets)) {
if (MOZ_UNLIKELY(!set.EnsureInserted(sheet))) {
// Cycle collection helper functions
void TraverseSheetRefInStylesIfApplicable(
StyleSheet&, nsCycleCollectionTraversalCallback&);
void TraverseStyleSheets(nsTArray<RefPtr<StyleSheet>>&, const char*,
void UnlinkStyleSheets(nsTArray<RefPtr<StyleSheet>>&);
using StyleSheetSet = nsTHashSet<const StyleSheet*>;
void RemoveSheetFromStylesIfApplicable(StyleSheet&);
void ClearAdoptedStyleSheets();
* Clone's the argument's adopted style sheets into this.
* This should only be used when cloning a static document for printing.
void CloneAdoptedSheetsFrom(const DocumentOrShadowRoot&);
void InsertSheetAt(size_t aIndex, StyleSheet& aSheet);
void AddSizeOfExcludingThis(nsWindowSizes&) const;
void AddSizeOfOwnedSheetArrayExcludingThis(
nsWindowSizes&, const nsTArray<RefPtr<StyleSheet>>&) const;
* If focused element's subtree root is this document or shadow root, return
* focused element, otherwise, get the shadow host recursively until the
* shadow host's subtree root is this document or shadow root.
Element* GetRetargetedFocusedElement();
nsTArray<RefPtr<StyleSheet>> mStyleSheets;
RefPtr<StyleSheetList> mDOMStyleSheets;
* Style sheets that are adopted by assinging to the `adoptedStyleSheets`
* WebIDL atribute. These can only be constructed stylesheets.
nsTArray<RefPtr<StyleSheet>> mAdoptedStyleSheets;
* mIdentifierMap works as follows for IDs:
* 1) Attribute changes affect the table immediately (removing and adding
* entries as needed).
* 2) Removals from the DOM affect the table immediately
* 3) Additions to the DOM always update existing entries for names, and add
* new ones for IDs.
nsTHashtable<IdentifierMapEntry> mIdentifierMap;
// Always non-null, see comment in the constructor as to why a pointer instead
// of a reference.
nsINode* mAsNode;
const Kind mKind;
inline const nsTArray<Element*>* DocumentOrShadowRoot::GetAllElementsForId(
const nsAString& aElementId) const {
if (aElementId.IsEmpty()) {
return nullptr;
IdentifierMapEntry* entry = mIdentifierMap.GetEntry(aElementId);
return entry ? &entry->GetIdElements() : nullptr;
} // namespace dom
} // namespace mozilla