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

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

layout/svg/nsSVGFilterFrame.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 "nsSVGFilterFrame.h"
 // Keep others in (case-insensitive) order:
 #include "gfxUtils.h"
 #include "nsGkAtoms.h"
 #include "nsRenderingContext.h"
 #include "nsSVGEffects.h"
 #include "nsSVGElement.h"
 #include "mozilla/dom/SVGFilterElement.h"
 #include "nsSVGFilterInstance.h"
 #include "nsSVGFilterPaintCallback.h"
 #include "nsSVGIntegrationUtils.h"
 #include "nsSVGUtils.h"
 #include "nsContentUtils.h"
 using namespace mozilla::dom;
 nsIFrame*
 NS_NewSVGFilterFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
 {
   return new (aPresShell) nsSVGFilterFrame(aContext);
 }
 NS_IMPL_FRAMEARENA_HELPERS(nsSVGFilterFrame)
 class MOZ_STACK_CLASS nsSVGFilterFrame::AutoFilterReferencer
 {
 public:
   AutoFilterReferencer(nsSVGFilterFrame *aFrame MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
     : mFrame(aFrame)
   {
     MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     // Reference loops should normally be detected in advance and handled, so
     // we're not expecting to encounter them here
     NS_ABORT_IF_FALSE(!mFrame->mLoopFlag, "Undetected reference loop!");
     mFrame->mLoopFlag = true;
   }
   ~AutoFilterReferencer() {
     mFrame->mLoopFlag = false;
   }
 private:
   nsSVGFilterFrame *mFrame;
   MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 uint16_t
 nsSVGFilterFrame::GetEnumValue(uint32_t aIndex, nsIContent *aDefault)
 {
   nsSVGEnum& thisEnum =
     static_cast<SVGFilterElement *>(mContent)->mEnumAttributes[aIndex];
   if (thisEnum.IsExplicitlySet())
     return thisEnum.GetAnimValue();
   AutoFilterReferencer filterRef(this);
   nsSVGFilterFrame *next = GetReferencedFilterIfNotInUse();
   return next ? next->GetEnumValue(aIndex, aDefault) :
     static_cast<SVGFilterElement *>(aDefault)->
       mEnumAttributes[aIndex].GetAnimValue();
 }
 const nsSVGLength2 *
 nsSVGFilterFrame::GetLengthValue(uint32_t aIndex, nsIContent *aDefault)
 {
   const nsSVGLength2 *thisLength =
     &static_cast<SVGFilterElement *>(mContent)->mLengthAttributes[aIndex];
   if (thisLength->IsExplicitlySet())
     return thisLength;
   AutoFilterReferencer filterRef(this);
   nsSVGFilterFrame *next = GetReferencedFilterIfNotInUse();
   return next ? next->GetLengthValue(aIndex, aDefault) :
     &static_cast<SVGFilterElement *>(aDefault)->mLengthAttributes[aIndex];
 }
 const SVGFilterElement *
 nsSVGFilterFrame::GetFilterContent(nsIContent *aDefault)
 {
   for (nsIContent* child = mContent->GetFirstChild();
        child;
        child = child->GetNextSibling()) {
     nsRefPtr<nsSVGFE> primitive;
     CallQueryInterface(child, (nsSVGFE**)getter_AddRefs(primitive));
     if (primitive) {
       return static_cast<SVGFilterElement *>(mContent);
     }
   }
   AutoFilterReferencer filterRef(this);
   nsSVGFilterFrame *next = GetReferencedFilterIfNotInUse();
   return next ? next->GetFilterContent(aDefault) :
     static_cast<SVGFilterElement *>(aDefault);
 }
 nsSVGFilterFrame *
 nsSVGFilterFrame::GetReferencedFilter()
 {
   if (mNoHRefURI)
     return nullptr;
   nsSVGPaintingProperty *property = static_cast<nsSVGPaintingProperty*>
     (Properties().Get(nsSVGEffects::HrefProperty()));
   if (!property) {
     // Fetch our Filter element's xlink:href attribute
     SVGFilterElement *filter = static_cast<SVGFilterElement *>(mContent);
     nsAutoString href;
     filter->mStringAttributes[SVGFilterElement::HREF].GetAnimValue(href, filter);
     if (href.IsEmpty()) {
       mNoHRefURI = true;
       return nullptr; // no URL
     }
     // Convert href to an nsIURI
     nsCOMPtr<nsIURI> targetURI;
     nsCOMPtr<nsIURI> base = mContent->GetBaseURI();
     nsContentUtils::NewURIWithDocumentCharset(getter_AddRefs(targetURI), href,
                                               mContent->GetCurrentDoc(), base);
     property =
       nsSVGEffects::GetPaintingProperty(targetURI, this, nsSVGEffects::HrefProperty());
     if (!property)
       return nullptr;
   }
   nsIFrame *result = property->GetReferencedFrame();
   if (!result)
     return nullptr;
   nsIAtom* frameType = result->GetType();
   if (frameType != nsGkAtoms::svgFilterFrame)
     return nullptr;
   return static_cast<nsSVGFilterFrame*>(result);
 }
 nsSVGFilterFrame *
 nsSVGFilterFrame::GetReferencedFilterIfNotInUse()
 {
   nsSVGFilterFrame *referenced = GetReferencedFilter();
   if (!referenced)
     return nullptr;
   if (referenced->mLoopFlag) {
     // XXXjwatt: we should really send an error to the JavaScript Console here:
     NS_WARNING("Filter reference loop detected while inheriting attribute!");
     return nullptr;
   }
   return referenced;
 }
 nsresult
 nsSVGFilterFrame::AttributeChanged(int32_t  aNameSpaceID,
                                    nsIAtom* aAttribute,
                                    int32_t  aModType)
 {
   if (aNameSpaceID == kNameSpaceID_None &&
       (aAttribute == nsGkAtoms::x ||
        aAttribute == nsGkAtoms::y ||
        aAttribute == nsGkAtoms::width ||
        aAttribute == nsGkAtoms::height ||
        aAttribute == nsGkAtoms::filterUnits ||
        aAttribute == nsGkAtoms::primitiveUnits)) {
     nsSVGEffects::InvalidateDirectRenderingObservers(this);
   } else if (aNameSpaceID == kNameSpaceID_XLink &&
              aAttribute == nsGkAtoms::href) {
     // Blow away our reference, if any
     Properties().Delete(nsSVGEffects::HrefProperty());
     mNoHRefURI = false;
     // And update whoever references us
     nsSVGEffects::InvalidateDirectRenderingObservers(this);
   }
   return nsSVGFilterFrameBase::AttributeChanged(aNameSpaceID,
                                                 aAttribute, aModType);
 }
 #ifdef DEBUG
 void
 nsSVGFilterFrame::Init(nsIContent* aContent,
                        nsIFrame* aParent,
                        nsIFrame* aPrevInFlow)
 {
   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::filter),
                "Content is not an SVG filter");
   nsSVGFilterFrameBase::Init(aContent, aParent, aPrevInFlow);
 }
 #endif /* DEBUG */
 nsIAtom *
 nsSVGFilterFrame::GetType() const
 {
   return nsGkAtoms::svgFilterFrame;
 }

The Tor Browser / annotate

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

layout/svg/nsSVGFilterFrame.cpp