The Tor Browser: layout/svg/nsSVGUseFrame.cpp@97036ab72558 (annotated)

layout/svg/nsSVGUseFrame.cpp@97036ab72558 (annotated)

layout/svg/nsSVGUseFrame.cpp

Tue, 06 Jan 2015 21:39:09 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 06 Jan 2015 21:39:09 +0100
branch: TOR_BUG_9701
changeset 8: 97036ab72558
permissions: -rw-r--r--

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* 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/. */
 // Keep in (case-insensitive) order:
 #include "nsIAnonymousContentCreator.h"
 #include "nsSVGEffects.h"
 #include "nsSVGGFrame.h"
 #include "mozilla/dom/SVGUseElement.h"
 #include "nsContentList.h"
 typedef nsSVGGFrame nsSVGUseFrameBase;
 using namespace mozilla::dom;
 class nsSVGUseFrame : public nsSVGUseFrameBase,
                       public nsIAnonymousContentCreator
 {
   friend nsIFrame*
   NS_NewSVGUseFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);
 protected:
   nsSVGUseFrame(nsStyleContext* aContext) :
     nsSVGUseFrameBase(aContext),
     mHasValidDimensions(true)
   {}
 public:
   NS_DECL_QUERYFRAME
   NS_DECL_FRAMEARENA_HELPERS
   // nsIFrame interface:
   virtual void Init(nsIContent*      aContent,
                     nsIFrame*        aParent,
                     nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
   virtual nsresult  AttributeChanged(int32_t         aNameSpaceID,
                                      nsIAtom*        aAttribute,
                                      int32_t         aModType) MOZ_OVERRIDE;
   virtual void DestroyFrom(nsIFrame* aDestructRoot) MOZ_OVERRIDE;
   /**
    * Get the "type" of the frame
    *
    * @see nsGkAtoms::svgUseFrame
    */
   virtual nsIAtom* GetType() const MOZ_OVERRIDE;
   virtual bool IsLeaf() const MOZ_OVERRIDE;
 #ifdef DEBUG_FRAME_DUMP
   virtual nsresult GetFrameName(nsAString& aResult) const MOZ_OVERRIDE
   {
     return MakeFrameName(NS_LITERAL_STRING("SVGUse"), aResult);
   }
 #endif
   // nsISVGChildFrame interface:
   virtual void ReflowSVG() MOZ_OVERRIDE;
   virtual void NotifySVGChanged(uint32_t aFlags) MOZ_OVERRIDE;
   // nsIAnonymousContentCreator
   virtual nsresult CreateAnonymousContent(nsTArray<ContentInfo>& aElements) MOZ_OVERRIDE;
   virtual void AppendAnonymousContentTo(nsBaseContentList& aElements,
                                         uint32_t aFilter) MOZ_OVERRIDE;
 private:
   bool mHasValidDimensions;
 };
 //----------------------------------------------------------------------
 // Implementation
 nsIFrame*
 NS_NewSVGUseFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
 {
   return new (aPresShell) nsSVGUseFrame(aContext);
 }
 NS_IMPL_FRAMEARENA_HELPERS(nsSVGUseFrame)
 nsIAtom *
 nsSVGUseFrame::GetType() const
 {
   return nsGkAtoms::svgUseFrame;
 }
 //----------------------------------------------------------------------
 // nsQueryFrame methods
 NS_QUERYFRAME_HEAD(nsSVGUseFrame)
   NS_QUERYFRAME_ENTRY(nsIAnonymousContentCreator)
 NS_QUERYFRAME_TAIL_INHERITING(nsSVGUseFrameBase)
 //----------------------------------------------------------------------
 // nsIFrame methods:
 void
 nsSVGUseFrame::Init(nsIContent* aContent,
                     nsIFrame* aParent,
                     nsIFrame* aPrevInFlow)
 {
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::use),
                "Content is not an SVG use!");
   mHasValidDimensions =
     static_cast<SVGUseElement*>(aContent)->HasValidDimensions();
   nsSVGUseFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 nsresult
 nsSVGUseFrame::AttributeChanged(int32_t         aNameSpaceID,
                                 nsIAtom*        aAttribute,
                                 int32_t         aModType)
 {
   SVGUseElement *useElement = static_cast<SVGUseElement*>(mContent);
   if (aNameSpaceID == kNameSpaceID_None) {
     if (aAttribute == nsGkAtoms::x ||
         aAttribute == nsGkAtoms::y) {
       // make sure our cached transform matrix gets (lazily) updated
       mCanvasTM = nullptr;
       nsSVGEffects::InvalidateRenderingObservers(this);
       nsSVGUtils::ScheduleReflowSVG(this);
       nsSVGUtils::NotifyChildrenOfSVGChange(this, TRANSFORM_CHANGED);
     } else if (aAttribute == nsGkAtoms::width ||
                aAttribute == nsGkAtoms::height) {
       bool invalidate = false;
       if (mHasValidDimensions != useElement->HasValidDimensions()) {
         mHasValidDimensions = !mHasValidDimensions;
         invalidate = true;
       }
       if (useElement->OurWidthAndHeightAreUsed()) {
         invalidate = true;
         useElement->SyncWidthOrHeight(aAttribute);
       }
       if (invalidate) {
         nsSVGEffects::InvalidateRenderingObservers(this);
         nsSVGUtils::ScheduleReflowSVG(this);
       }
     }
   } else if (aNameSpaceID == kNameSpaceID_XLink &&
              aAttribute == nsGkAtoms::href) {
     // we're changing our nature, clear out the clone information
     nsSVGEffects::InvalidateRenderingObservers(this);
     nsSVGUtils::ScheduleReflowSVG(this);
     useElement->mOriginal = nullptr;
     useElement->UnlinkSource();
     useElement->TriggerReclone();
   }
   return nsSVGUseFrameBase::AttributeChanged(aNameSpaceID,
                                              aAttribute, aModType);
 }
 void
 nsSVGUseFrame::DestroyFrom(nsIFrame* aDestructRoot)
 {
   nsRefPtr<SVGUseElement> use = static_cast<SVGUseElement*>(mContent);
   nsSVGUseFrameBase::DestroyFrom(aDestructRoot);
   use->DestroyAnonymousContent();
 }
 bool
 nsSVGUseFrame::IsLeaf() const
 {
   return true;
 }
 //----------------------------------------------------------------------
 // nsISVGChildFrame methods
 void
 nsSVGUseFrame::ReflowSVG()
 {
   // We only handle x/y offset here, since any width/height that is in force is
   // handled by the nsSVGOuterSVGFrame for the anonymous <svg> that will be
   // created for that purpose.
   float x, y;
   static_cast<SVGUseElement*>(mContent)->
     GetAnimatedLengthValues(&x, &y, nullptr);
   mRect.MoveTo(nsLayoutUtils::RoundGfxRectToAppRect(
                  gfxRect(x, y, 0.0, 0.0),
                  PresContext()->AppUnitsPerCSSPixel()).TopLeft());
   // If we have a filter, we need to invalidate ourselves because filter
   // output can change even if none of our descendants need repainting.
   if (StyleSVGReset()->HasFilters()) {
     InvalidateFrame();
   }
   nsSVGUseFrameBase::ReflowSVG();
 }
 void
 nsSVGUseFrame::NotifySVGChanged(uint32_t aFlags)
 {
   if (aFlags & COORD_CONTEXT_CHANGED &&
       !(aFlags & TRANSFORM_CHANGED)) {
     // Coordinate context changes affect mCanvasTM if we have a
     // percentage 'x' or 'y'
     SVGUseElement *use = static_cast<SVGUseElement*>(mContent);
     if (use->mLengthAttributes[SVGUseElement::ATTR_X].IsPercentage() ||
         use->mLengthAttributes[SVGUseElement::ATTR_Y].IsPercentage()) {
       aFlags |= TRANSFORM_CHANGED;
       // Ancestor changes can't affect how we render from the perspective of
       // any rendering observers that we may have, so we don't need to
       // invalidate them. We also don't need to invalidate ourself, since our
       // changed ancestor will have invalidated its entire area, which includes
       // our area.
       // For perf reasons we call this before calling NotifySVGChanged() below.
       nsSVGUtils::ScheduleReflowSVG(this);
     }
   }
   // We don't remove the TRANSFORM_CHANGED flag here if we have a viewBox or
   // non-percentage width/height, since if they're set then they are cloned to
   // an anonymous child <svg>, and its nsSVGInnerSVGFrame will do that.
   nsSVGUseFrameBase::NotifySVGChanged(aFlags);
 }
 //----------------------------------------------------------------------
 // nsIAnonymousContentCreator methods:
 nsresult
 nsSVGUseFrame::CreateAnonymousContent(nsTArray<ContentInfo>& aElements)
 {
   SVGUseElement *use = static_cast<SVGUseElement*>(mContent);
   nsIContent* clone = use->CreateAnonymousContent();
   nsSVGEffects::InvalidateRenderingObservers(this);
   if (!clone)
     return NS_ERROR_FAILURE;
   if (!aElements.AppendElement(clone))
     return NS_ERROR_OUT_OF_MEMORY;
   return NS_OK;
 }
 void
 nsSVGUseFrame::AppendAnonymousContentTo(nsBaseContentList& aElements,
                                         uint32_t aFilter)
 {
   SVGUseElement *use = static_cast<SVGUseElement*>(mContent);
   nsIContent* clone = use->GetAnonymousContent();
   aElements.MaybeAppendElement(clone);
 }

The Tor Browser / annotate

layout/svg/nsSVGUseFrame.cpp@97036ab72558 (annotated)

layout/svg/nsSVGUseFrame.cpp