From 36d22d82aa202bb199967e9512281e9a53db42c9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 21:33:14 +0200 Subject: Adding upstream version 115.7.0esr. Signed-off-by: Daniel Baumann --- layout/svg/SVGObserverUtils.h | 420 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 420 insertions(+) create mode 100644 layout/svg/SVGObserverUtils.h (limited to 'layout/svg/SVGObserverUtils.h') diff --git a/layout/svg/SVGObserverUtils.h b/layout/svg/SVGObserverUtils.h new file mode 100644 index 0000000000..17bd012078 --- /dev/null +++ b/layout/svg/SVGObserverUtils.h @@ -0,0 +1,420 @@ +/* -*- 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 LAYOUT_SVG_SVGOBSERVERUTILS_H_ +#define LAYOUT_SVG_SVGOBSERVERUTILS_H_ + +#include "mozilla/Attributes.h" +#include "mozilla/dom/IDTracker.h" +#include "FrameProperties.h" +#include "nsID.h" +#include "nsIFrame.h" // only for LayoutFrameType +#include "nsIMutationObserver.h" +#include "nsISupports.h" +#include "nsISupportsImpl.h" +#include "nsIReferrerInfo.h" +#include "nsStringFwd.h" +#include "nsStubMutationObserver.h" +#include "nsStyleStruct.h" +#include "nsCycleCollectionParticipant.h" + +class nsAtom; +class nsIFrame; +class nsIURI; + +namespace mozilla { +class SVGClipPathFrame; +class SVGFilterFrame; +class SVGMarkerFrame; +class SVGMaskFrame; +class SVGPaintServerFrame; + +namespace dom { +class CanvasRenderingContext2D; +class Element; +class SVGGeometryElement; +} // namespace dom +} // namespace mozilla + +namespace mozilla { + +/* + * This class contains URL and referrer information (referrer and referrer + * policy). + * We use it to pass to svg system instead of nsIURI. The object brings referrer + * and referrer policy so we can send correct Referer headers. + */ +class URLAndReferrerInfo { + public: + URLAndReferrerInfo(nsIURI* aURI, nsIReferrerInfo* aReferrerInfo) + : mURI(aURI), mReferrerInfo(aReferrerInfo) { + MOZ_ASSERT(aURI); + } + + URLAndReferrerInfo(nsIURI* aURI, const URLExtraData& aExtraData) + : mURI(aURI), mReferrerInfo(aExtraData.ReferrerInfo()) { + MOZ_ASSERT(aURI); + } + + NS_INLINE_DECL_REFCOUNTING(URLAndReferrerInfo) + + nsIURI* GetURI() const { return mURI; } + nsIReferrerInfo* GetReferrerInfo() const { return mReferrerInfo; } + + bool operator==(const URLAndReferrerInfo& aRHS) const; + + private: + ~URLAndReferrerInfo() = default; + + nsCOMPtr mURI; + nsCOMPtr mReferrerInfo; +}; + +/** + * This interface allows us to be notified when a piece of SVG content is + * re-rendered. + * + * Concrete implementations of this base class need to implement + * GetReferencedElementWithoutObserving to specify the SVG element that + * they'd like to monitor for rendering changes, and they need to implement + * OnRenderingChange to specify how we'll react when that content gets + * re-rendered. They also need to implement a constructor and destructor, + * which should call StartObserving and StopObserving, respectively. + * + * The referenced element is generally looked up and stored during + * construction. If the referenced element is in an extenal SVG resource + * document, the lookup code will initiate loading of the external resource and + * OnRenderingChange will be called once the element in the external resource + * is available. + * + * Although the referenced element may be found and stored during construction, + * observing for rendering changes does not start until requested. + */ +class SVGRenderingObserver : public nsStubMutationObserver { + protected: + virtual ~SVGRenderingObserver() = default; + + public: + using Element = dom::Element; + + SVGRenderingObserver() : mInObserverSet(false) {} + + // nsIMutationObserver + NS_DECL_NSIMUTATIONOBSERVER_ATTRIBUTECHANGED + NS_DECL_NSIMUTATIONOBSERVER_CONTENTAPPENDED + NS_DECL_NSIMUTATIONOBSERVER_CONTENTINSERTED + NS_DECL_NSIMUTATIONOBSERVER_CONTENTREMOVED + + /** + * Called when non-DOM-mutation changes to the observed element should likely + * cause the rendering of our observer to change. This includes changes to + * CSS computed values, but also changes to rendering observers that the + * observed element itself may have (for example, when we're being used to + * observe an SVG pattern, and an element in that pattern references and + * observes a gradient that has changed). + */ + void OnNonDOMMutationRenderingChange(); + + // When a SVGRenderingObserver list gets forcibly cleared, it uses this + // callback to notify every observer that's cleared from it, so they can + // react. + void NotifyEvictedFromRenderingObserverSet(); + + nsIFrame* GetAndObserveReferencedFrame(); + /** + * @param aOK this is only for the convenience of callers. We set *aOK to + * false if the frame is the wrong type + */ + nsIFrame* GetAndObserveReferencedFrame(mozilla::LayoutFrameType aFrameType, + bool* aOK); + + Element* GetAndObserveReferencedElement(); + + virtual bool ObservesReflow() { return false; } + + protected: + void StartObserving(); + void StopObserving(); + + /** + * Called whenever the rendering of the observed element may have changed. + * + * More specifically, this method is called whenever DOM mutation occurs in + * the observed element's subtree, or whenever + * SVGObserverUtils::InvalidateRenderingObservers or + * SVGObserverUtils::InvalidateDirectRenderingObservers is called for the + * observed element's frame. + * + * Subclasses should override this method to handle rendering changes + * appropriately. + */ + virtual void OnRenderingChange() = 0; + + virtual Element* GetReferencedElementWithoutObserving() = 0; + +#ifdef DEBUG + void DebugObserverSet(); +#endif + + // Whether we're in our observed element's observer set at this time. + bool mInObserverSet; +}; + +class SVGObserverUtils { + public: + using CanvasRenderingContext2D = dom::CanvasRenderingContext2D; + using Element = dom::Element; + using SVGGeometryElement = dom::SVGGeometryElement; + using HrefToTemplateCallback = const std::function&; + + /** + * Ensures that that if the given frame requires any resources that are in + * SVG resource documents that the loading of those documents is initiated. + * This does not make aFrame start to observe any elements that it + * references. + */ + static void InitiateResourceDocLoads(nsIFrame* aFrame); + + /** + * Called when changes to an element (e.g. CSS property changes) cause its + * frame to start/stop referencing (or reference different) SVG resource + * elements. (_Not_ called for changes to referenced resource elements.) + * + * This function handles such changes by discarding _all_ the frame's SVG + * effects frame properties (causing those properties to stop watching their + * target element). It also synchronously (re)creates the filter and marker + * frame properties (XXX why not the other properties?), which makes it + * useful for initializing those properties during first reflow. + * + * XXX rename to something more meaningful like RefreshResourceReferences? + */ + static void UpdateEffects(nsIFrame* aFrame); + + /** + * @param aFrame must be a first-continuation. + */ + static void AddRenderingObserver(Element* aElement, + SVGRenderingObserver* aObserver); + /** + * @param aFrame must be a first-continuation. + */ + static void RemoveRenderingObserver(Element* aElement, + SVGRenderingObserver* aObserver); + + /** + * Removes all rendering observers from aElement. + */ + static void RemoveAllRenderingObservers(Element* aElement); + + /** + * This can be called on any frame. We invalidate the observers of aFrame's + * element, if any, or else walk up to the nearest observable SVG parent + * frame with observers and invalidate them instead. + * + * Note that this method is very different to e.g. + * MutationObservers::AttributeChanged which walks up the content node tree + * all the way to the root node (not stopping if it encounters a non-container + * SVG node) invalidating all mutation observers (not just + * SVGRenderingObservers) on all nodes along the way (not just the first + * node it finds with observers). In other words, by doing all the + * things in parentheses in the preceding sentence, this method uses + * knowledge about our implementation and what can be affected by SVG effects + * to make invalidation relatively lightweight when an SVG effect changes. + */ + static void InvalidateRenderingObservers(nsIFrame* aFrame); + + enum { INVALIDATE_REFLOW = 1 }; + + enum ReferenceState { + /// Has no references to SVG filters (may still have CSS filter functions!) + eHasNoRefs, + eHasRefsAllValid, + eHasRefsSomeInvalid, + }; + + /** + * This can be called on any element or frame. Only direct observers of this + * (frame's) element, if any, are invalidated. + */ + static void InvalidateDirectRenderingObservers(Element* aElement, + uint32_t aFlags = 0); + static void InvalidateDirectRenderingObservers(nsIFrame* aFrame, + uint32_t aFlags = 0); + + /** + * Get the paint server for aPaintedFrame. + */ + static SVGPaintServerFrame* GetAndObservePaintServer( + nsIFrame* aPaintedFrame, mozilla::StyleSVGPaint nsStyleSVG::*aPaint); + + /** + * Get the start/mid/end-markers for the given frame, and add the frame as + * an observer to those markers. Returns true if at least one marker type is + * found, false otherwise. + */ + static bool GetAndObserveMarkers(nsIFrame* aMarkedFrame, + SVGMarkerFrame* (*aFrames)[3]); + + /** + * Get the frames of the SVG filters applied to the given frame, and add the + * frame as an observer to those filter frames. + * + * NOTE! A return value of eHasNoRefs does NOT mean that there are no filters + * to be applied, only that there are no references to SVG filter elements. + * + * XXX Callers other than ComputePostEffectsInkOverflowRect and + * SVGUtils::GetPostFilterInkOverflowRect should not need to initiate + * observing. If we have a bug that causes invalidation (which would remove + * observers) between reflow and painting, then we don't really want to + * re-add abservers during painting. That has the potential to hide logic + * bugs, or cause later invalidation problems. However, let's not change + * that behavior just yet due to the regression potential. + */ + static ReferenceState GetAndObserveFilters( + nsIFrame* aFilteredFrame, nsTArray* aFilterFrames); + + /** + * If the given frame is already observing SVG filters, this function gets + * those filters. If the frame is not already observing filters this + * function assumes that it doesn't have anything to observe. + */ + static ReferenceState GetFiltersIfObserving( + nsIFrame* aFilteredFrame, nsTArray* aFilterFrames); + + /** + * Starts observing filters for a element's CanvasRenderingContext2D. + * + * Returns a RAII object that the caller should make sure is released once + * the CanvasRenderingContext2D is no longer using them (that is, when the + * CanvasRenderingContext2D "drawing style state" on which the filters were + * set is destroyed or has its filter style reset). + * + * XXXjwatt: It's a bit unfortunate that both we and + * CanvasRenderingContext2D::UpdateFilter process the list of StyleFilter + * objects separately. It would be better to refactor things so that we only + * do that work once. + */ + static already_AddRefed ObserveFiltersForCanvasContext( + CanvasRenderingContext2D* aContext, Element* aCanvasElement, + Span aFilters); + + /** + * Called when cycle collecting CanvasRenderingContext2D, and requires the + * RAII object returned from ObserveFiltersForCanvasContext to be passed in. + * + * XXXjwatt: I don't think this is doing anything useful. All we do under + * this function is clear a raw C-style (i.e. not strong) pointer. That's + * clearly not helping in breaking any cycles. The fact that we MOZ_CRASH + * in OnRenderingChange if that pointer is null indicates that this isn't + * even doing anything useful in terms of preventing further invalidation + * from any observed filters. + */ + static void DetachFromCanvasContext(nsISupports* aAutoObserver); + + /** + * Get the frame of the SVG clipPath applied to aClippedFrame, if any, and + * set up aClippedFrame as a rendering observer of the clipPath's frame, to + * be invalidated if it changes. + * + * Currently we only have support for 'clip-path' with a single item, but the + * spec. now says 'clip-path' can be set to an arbitrary number of items. + * Once we support that, aClipPathFrame will need to be an nsTArray as it + * is for 'filter' and 'mask'. Currently a return value of eHasNoRefs means + * that there is no clipping at all, but once we support more than one item + * then - as for filter and mask - we could still have basic shape clipping + * to apply even if there are no references to SVG clipPath elements. + * + * Note that, unlike for filters, a reference to an ID that doesn't exist + * is not invalid for clip-path or mask. We will return eHasNoRefs in that + * case. + */ + static ReferenceState GetAndObserveClipPath( + nsIFrame* aClippedFrame, SVGClipPathFrame** aClipPathFrame); + + /** + * If masking is applied to aMaskedFrame, gets an array of any SVG masks + * that are referenced, setting up aMaskFrames as a rendering observer of + * those masks (if any). + * + * NOTE! A return value of eHasNoRefs does NOT mean that there are no masks + * to be applied, only that there are no references to SVG mask elements. + * + * Note that, unlike for filters, a reference to an ID that doesn't exist + * is not invalid for clip-path or mask. We will return eHasNoRefs in that + * case. + */ + static ReferenceState GetAndObserveMasks( + nsIFrame* aMaskedFrame, nsTArray* aMaskFrames); + + /** + * Get the SVGGeometryElement that is referenced by aTextPathFrame, and make + * aTextPathFrame start observing rendering changes to that element. + */ + static SVGGeometryElement* GetAndObserveTextPathsPath( + nsIFrame* aTextPathFrame); + + /** + * Make aTextPathFrame stop observing rendering changes to the + * SVGGeometryElement that it references, if any. + */ + static void RemoveTextPathObserver(nsIFrame* aTextPathFrame); + + /** + * Gets the nsIFrame of a referenced SVG "template" element, if any, and + * makes aFrame start observing rendering changes to the template element. + * + * Template elements: some elements like gradients, pattern or filter can + * reference another element of the same type using their 'href' attribute, + * and use that element as a template that provides attributes or content + * that is missing from the referring element. + * + * The frames that this function is called for do not have a common base + * class, which is why it is necessary to pass in a function that can be + * used as a callback to lazily get the href value, if necessary. + */ + static nsIFrame* GetAndObserveTemplate(nsIFrame* aFrame, + HrefToTemplateCallback aGetHref); + + static void RemoveTemplateObserver(nsIFrame* aFrame); + + /** + * Gets an arbitrary element and starts observing it. Used to implement + * '-moz-element'. + * + * Note that bug 1496065 has been filed to remove support for referencing + * arbitrary elements using '-moz-element'. + */ + static Element* GetAndObserveBackgroundImage(nsIFrame* aFrame, + const nsAtom* aHref); + + /** + * Gets an arbitrary element and starts observing it. Used to detect + * invalidation changes for background-clip:text. + */ + static Element* GetAndObserveBackgroundClip(nsIFrame* aFrame); + + /** + * A helper function to resolve filter URL. + */ + static already_AddRefed GetFilterURI( + nsIFrame* aFrame, const StyleFilter& aFilter); + + /** + * Return a baseURL for resolving a local-ref URL. + * + * @param aContent an element which uses a local-ref property. Here are some + * examples: + * + * + * + */ + static already_AddRefed GetBaseURLForLocalRef(nsIContent* aContent, + nsIURI* aDocURI); +}; + +} // namespace mozilla + +#endif // LAYOUT_SVG_SVGOBSERVERUTILS_H_ -- cgit v1.2.3