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

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

layout/svg/nsSVGInnerSVGFrame.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/. */
 // Main header first:
 #include "nsSVGInnerSVGFrame.h"
 // Keep others in (case-insensitive) order:
 #include "gfxContext.h"
 #include "nsIFrame.h"
 #include "nsISVGChildFrame.h"
 #include "nsRenderingContext.h"
 #include "nsSVGContainerFrame.h"
 #include "nsSVGEffects.h"
 #include "nsSVGIntegrationUtils.h"
 #include "mozilla/dom/SVGSVGElement.h"
 using namespace mozilla;
 using namespace mozilla::dom;
 nsIFrame*
 NS_NewSVGInnerSVGFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
 {
   return new (aPresShell) nsSVGInnerSVGFrame(aContext);
 }
 NS_IMPL_FRAMEARENA_HELPERS(nsSVGInnerSVGFrame)
 //----------------------------------------------------------------------
 // nsIFrame methods
 NS_QUERYFRAME_HEAD(nsSVGInnerSVGFrame)
   NS_QUERYFRAME_ENTRY(nsSVGInnerSVGFrame)
   NS_QUERYFRAME_ENTRY(nsISVGSVGFrame)
 NS_QUERYFRAME_TAIL_INHERITING(nsSVGInnerSVGFrameBase)
 #ifdef DEBUG
 void
 nsSVGInnerSVGFrame::Init(nsIContent* aContent,
                          nsIFrame* aParent,
                          nsIFrame* aPrevInFlow)
 {
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::svg),
                "Content is not an SVG 'svg' element!");
   nsSVGInnerSVGFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 nsIAtom *
 nsSVGInnerSVGFrame::GetType() const
 {
   return nsGkAtoms::svgInnerSVGFrame;
 }
 //----------------------------------------------------------------------
 // nsISVGChildFrame methods
 nsresult
 nsSVGInnerSVGFrame::PaintSVG(nsRenderingContext *aContext,
                              const nsIntRect *aDirtyRect,
                              nsIFrame* aTransformRoot)
 {
   NS_ASSERTION(!NS_SVGDisplayListPaintingEnabled() ||
                (mState & NS_FRAME_IS_NONDISPLAY),
                "If display lists are enabled, only painting of non-display "
                "SVG should take this code path");
   gfxContextAutoSaveRestore autoSR;
   if (StyleDisplay()->IsScrollableOverflow()) {
     float x, y, width, height;
     static_cast<SVGSVGElement*>(mContent)->
       GetAnimatedLengthValues(&x, &y, &width, &height, nullptr);
     if (width <= 0 || height <= 0) {
       return NS_OK;
     }
     nsSVGContainerFrame *parent = static_cast<nsSVGContainerFrame*>(mParent);
     gfxMatrix clipTransform = parent->GetCanvasTM(FOR_PAINTING, aTransformRoot);
     gfxContext *gfx = aContext->ThebesContext();
     autoSR.SetContext(gfx);
     gfxRect clipRect =
       nsSVGUtils::GetClipRectForFrame(this, x, y, width, height);
     nsSVGUtils::SetClipRect(gfx, clipTransform, clipRect);
   }
   return nsSVGInnerSVGFrameBase::PaintSVG(aContext, aDirtyRect);
 }
 void
 nsSVGInnerSVGFrame::ReflowSVG()
 {
   // mRect must be set before FinishAndStoreOverflow is called in order
   // for our overflow areas to be clipped correctly.
   float x, y, width, height;
   static_cast<SVGSVGElement*>(mContent)->
     GetAnimatedLengthValues(&x, &y, &width, &height, nullptr);
   mRect = nsLayoutUtils::RoundGfxRectToAppRect(
                            gfxRect(x, y, width, height),
                            PresContext()->AppUnitsPerCSSPixel());
   // 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();
   }
   nsSVGInnerSVGFrameBase::ReflowSVG();
 }
 void
 nsSVGInnerSVGFrame::NotifySVGChanged(uint32_t aFlags)
 {
   NS_ABORT_IF_FALSE(aFlags & (TRANSFORM_CHANGED | COORD_CONTEXT_CHANGED),
                     "Invalidation logic may need adjusting");
   if (aFlags & COORD_CONTEXT_CHANGED) {
     SVGSVGElement *svg = static_cast<SVGSVGElement*>(mContent);
     bool xOrYIsPercentage =
       svg->mLengthAttributes[SVGSVGElement::ATTR_X].IsPercentage() ||
       svg->mLengthAttributes[SVGSVGElement::ATTR_Y].IsPercentage();
     bool widthOrHeightIsPercentage =
       svg->mLengthAttributes[SVGSVGElement::ATTR_WIDTH].IsPercentage() ||
       svg->mLengthAttributes[SVGSVGElement::ATTR_HEIGHT].IsPercentage();
     if (xOrYIsPercentage || widthOrHeightIsPercentage) {
       // 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);
     }
     // Coordinate context changes affect mCanvasTM if we have a
     // percentage 'x' or 'y', or if we have a percentage 'width' or 'height' AND
     // a 'viewBox'.
     if (!(aFlags & TRANSFORM_CHANGED) &&
         (xOrYIsPercentage ||
          (widthOrHeightIsPercentage && svg->HasViewBoxRect()))) {
       aFlags |= TRANSFORM_CHANGED;
     }
     if (svg->HasViewBoxRect() || !widthOrHeightIsPercentage) {
       // Remove COORD_CONTEXT_CHANGED, since we establish the coordinate
       // context for our descendants and this notification won't change its
       // dimensions:
       aFlags &= ~COORD_CONTEXT_CHANGED;
       if (!aFlags) {
         return; // No notification flags left
       }
     }
   }
   if (aFlags & TRANSFORM_CHANGED) {
     // make sure our cached transform matrix gets (lazily) updated
     mCanvasTM = nullptr;
   }
   nsSVGInnerSVGFrameBase::NotifySVGChanged(aFlags);
 }
 nsresult
 nsSVGInnerSVGFrame::AttributeChanged(int32_t  aNameSpaceID,
                                      nsIAtom* aAttribute,
                                      int32_t  aModType)
 {
   if (aNameSpaceID == kNameSpaceID_None &&
       !(GetStateBits() & NS_FRAME_IS_NONDISPLAY)) {
     SVGSVGElement* content = static_cast<SVGSVGElement*>(mContent);
     if (aAttribute == nsGkAtoms::width ||
         aAttribute == nsGkAtoms::height) {
       nsSVGEffects::InvalidateRenderingObservers(this);
       nsSVGUtils::ScheduleReflowSVG(this);
       if (content->HasViewBoxOrSyntheticViewBox()) {
         // make sure our cached transform matrix gets (lazily) updated
         mCanvasTM = nullptr;
         content->ChildrenOnlyTransformChanged();
         nsSVGUtils::NotifyChildrenOfSVGChange(this, TRANSFORM_CHANGED);
       } else {
         uint32_t flags = COORD_CONTEXT_CHANGED;
         if (mCanvasTM && mCanvasTM->IsSingular()) {
           mCanvasTM = nullptr;
           flags |= TRANSFORM_CHANGED;
         }
         nsSVGUtils::NotifyChildrenOfSVGChange(this, flags);
       }
     } else if (aAttribute == nsGkAtoms::transform ||
                aAttribute == nsGkAtoms::preserveAspectRatio ||
                aAttribute == nsGkAtoms::viewBox ||
                aAttribute == nsGkAtoms::x ||
                aAttribute == nsGkAtoms::y) {
       // make sure our cached transform matrix gets (lazily) updated
       mCanvasTM = nullptr;
       nsSVGUtils::NotifyChildrenOfSVGChange(
           this, aAttribute == nsGkAtoms::viewBox ?
                   TRANSFORM_CHANGED | COORD_CONTEXT_CHANGED : TRANSFORM_CHANGED);
       // We don't invalidate for transform changes (the layers code does that).
       // Also note that SVGTransformableElement::GetAttributeChangeHint will
       // return nsChangeHint_UpdateOverflow for "transform" attribute changes
       // and cause DoApplyRenderingChangeToTree to make the SchedulePaint call.
       if (aAttribute == nsGkAtoms::x || aAttribute == nsGkAtoms::y) {
         nsSVGEffects::InvalidateRenderingObservers(this);
         nsSVGUtils::ScheduleReflowSVG(this);
       } else if (aAttribute == nsGkAtoms::viewBox ||
                  (aAttribute == nsGkAtoms::preserveAspectRatio &&
                   content->HasViewBoxOrSyntheticViewBox())) {
         content->ChildrenOnlyTransformChanged();
         // SchedulePaint sets a global state flag so we only need to call it once
         // (on ourself is fine), not once on each child (despite bug 828240).
         SchedulePaint();
       }
     }
   }
   return NS_OK;
 }
 nsIFrame*
 nsSVGInnerSVGFrame::GetFrameForPoint(const nsPoint &aPoint)
 {
   NS_ASSERTION(!NS_SVGDisplayListHitTestingEnabled() ||
                (mState & NS_FRAME_IS_NONDISPLAY),
                "If display lists are enabled, only hit-testing of non-display "
                "SVG should take this code path");
   if (StyleDisplay()->IsScrollableOverflow()) {
     nsSVGElement *content = static_cast<nsSVGElement*>(mContent);
     nsSVGContainerFrame *parent = static_cast<nsSVGContainerFrame*>(mParent);
     float clipX, clipY, clipWidth, clipHeight;
     content->GetAnimatedLengthValues(&clipX, &clipY, &clipWidth, &clipHeight, nullptr);
     if (!nsSVGUtils::HitTestRect(gfx::ToMatrix(parent->GetCanvasTM(FOR_HIT_TESTING)),
                                  clipX, clipY, clipWidth, clipHeight,
                                  PresContext()->AppUnitsToDevPixels(aPoint.x),
                                  PresContext()->AppUnitsToDevPixels(aPoint.y))) {
       return nullptr;
     }
   }
   return nsSVGInnerSVGFrameBase::GetFrameForPoint(aPoint);
 }
 //----------------------------------------------------------------------
 // nsISVGSVGFrame methods:
 void
 nsSVGInnerSVGFrame::NotifyViewportOrTransformChanged(uint32_t aFlags)
 {
   // The dimensions of inner-<svg> frames are purely defined by their "width"
   // and "height" attributes, and transform changes can only occur as a result
   // of changes to their "width", "height", "viewBox" or "preserveAspectRatio"
   // attributes. Changes to all of these attributes are handled in
   // AttributeChanged(), so we should never be called.
   NS_ERROR("Not called for nsSVGInnerSVGFrame");
 }
 //----------------------------------------------------------------------
 // nsSVGContainerFrame methods:
 gfxMatrix
 nsSVGInnerSVGFrame::GetCanvasTM(uint32_t aFor, nsIFrame* aTransformRoot)
 {
   if (!(GetStateBits() & NS_FRAME_IS_NONDISPLAY) && !aTransformRoot) {
     if ((aFor == FOR_PAINTING && NS_SVGDisplayListPaintingEnabled()) ||
         (aFor == FOR_HIT_TESTING && NS_SVGDisplayListHitTestingEnabled())) {
       return nsSVGIntegrationUtils::GetCSSPxToDevPxMatrix(this);
     }
   }
   if (!mCanvasTM) {
     NS_ASSERTION(mParent, "null parent");
     nsSVGContainerFrame *parent = static_cast<nsSVGContainerFrame*>(mParent);
     SVGSVGElement *content = static_cast<SVGSVGElement*>(mContent);
     gfxMatrix tm = content->PrependLocalTransformsTo(
         this == aTransformRoot ? gfxMatrix() :
                                  parent->GetCanvasTM(aFor, aTransformRoot));
     mCanvasTM = new gfxMatrix(tm);
   }
   return *mCanvasTM;
 }
 bool
 nsSVGInnerSVGFrame::HasChildrenOnlyTransform(gfx::Matrix *aTransform) const
 {
   SVGSVGElement *content = static_cast<SVGSVGElement*>(mContent);
   if (content->HasViewBoxOrSyntheticViewBox()) {
     // XXX Maybe return false if the transform is the identity transform?
     if (aTransform) {
       *aTransform = content->GetViewBoxTransform();
     }
     return true;
   }
   return false;
 }

The Tor Browser / annotate

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

layout/svg/nsSVGInnerSVGFrame.cpp