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

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.

     1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

     2 /* This Source Code Form is subject to the terms of the Mozilla Public

     3  * License, v. 2.0. If a copy of the MPL was not distributed with this

     4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

     6 // Main header first:

     7 #include "nsSVGFilterFrame.h"

     9 // Keep others in (case-insensitive) order:

    10 #include "gfxUtils.h"

    11 #include "nsGkAtoms.h"

    12 #include "nsRenderingContext.h"

    13 #include "nsSVGEffects.h"

    14 #include "nsSVGElement.h"

    15 #include "mozilla/dom/SVGFilterElement.h"

    16 #include "nsSVGFilterInstance.h"

    17 #include "nsSVGFilterPaintCallback.h"

    18 #include "nsSVGIntegrationUtils.h"

    19 #include "nsSVGUtils.h"

    20 #include "nsContentUtils.h"

    22 using namespace mozilla::dom;

    24 nsIFrame*

    25 NS_NewSVGFilterFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)

    26 {

    27   return new (aPresShell) nsSVGFilterFrame(aContext);

    28 }

    30 NS_IMPL_FRAMEARENA_HELPERS(nsSVGFilterFrame)

    32 class MOZ_STACK_CLASS nsSVGFilterFrame::AutoFilterReferencer

    33 {

    34 public:

    35   AutoFilterReferencer(nsSVGFilterFrame *aFrame MOZ_GUARD_OBJECT_NOTIFIER_PARAM)

    36     : mFrame(aFrame)

    37   {

    38     MOZ_GUARD_OBJECT_NOTIFIER_INIT;

    39     // Reference loops should normally be detected in advance and handled, so

    40     // we're not expecting to encounter them here

    41     NS_ABORT_IF_FALSE(!mFrame->mLoopFlag, "Undetected reference loop!");

    42     mFrame->mLoopFlag = true;

    43   }

    44   ~AutoFilterReferencer() {

    45     mFrame->mLoopFlag = false;

    46   }

    47 private:

    48   nsSVGFilterFrame *mFrame;

    49   MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER

    50 };

    52 uint16_t

    53 nsSVGFilterFrame::GetEnumValue(uint32_t aIndex, nsIContent *aDefault)

    54 {

    55   nsSVGEnum& thisEnum =

    56     static_cast<SVGFilterElement *>(mContent)->mEnumAttributes[aIndex];

    58   if (thisEnum.IsExplicitlySet())

    59     return thisEnum.GetAnimValue();

    61   AutoFilterReferencer filterRef(this);

    63   nsSVGFilterFrame *next = GetReferencedFilterIfNotInUse();

    64   return next ? next->GetEnumValue(aIndex, aDefault) :

    65     static_cast<SVGFilterElement *>(aDefault)->

    66       mEnumAttributes[aIndex].GetAnimValue();

    67 }

    69 const nsSVGLength2 *

    70 nsSVGFilterFrame::GetLengthValue(uint32_t aIndex, nsIContent *aDefault)

    71 {

    72   const nsSVGLength2 *thisLength =

    73     &static_cast<SVGFilterElement *>(mContent)->mLengthAttributes[aIndex];

    75   if (thisLength->IsExplicitlySet())

    76     return thisLength;

    78   AutoFilterReferencer filterRef(this);

    80   nsSVGFilterFrame *next = GetReferencedFilterIfNotInUse();

    81   return next ? next->GetLengthValue(aIndex, aDefault) :

    82     &static_cast<SVGFilterElement *>(aDefault)->mLengthAttributes[aIndex];

    83 }

    85 const SVGFilterElement *

    86 nsSVGFilterFrame::GetFilterContent(nsIContent *aDefault)

    87 {

    88   for (nsIContent* child = mContent->GetFirstChild();

    89        child;

    90        child = child->GetNextSibling()) {

    91     nsRefPtr<nsSVGFE> primitive;

    92     CallQueryInterface(child, (nsSVGFE**)getter_AddRefs(primitive));

    93     if (primitive) {

    94       return static_cast<SVGFilterElement *>(mContent);

    95     }

    96   }

    98   AutoFilterReferencer filterRef(this);

   100   nsSVGFilterFrame *next = GetReferencedFilterIfNotInUse();

   101   return next ? next->GetFilterContent(aDefault) :

   102     static_cast<SVGFilterElement *>(aDefault);

   103 }

   105 nsSVGFilterFrame *

   106 nsSVGFilterFrame::GetReferencedFilter()

   107 {

   108   if (mNoHRefURI)

   109     return nullptr;

   111   nsSVGPaintingProperty *property = static_cast<nsSVGPaintingProperty*>

   112     (Properties().Get(nsSVGEffects::HrefProperty()));

   114   if (!property) {

   115     // Fetch our Filter element's xlink:href attribute

   116     SVGFilterElement *filter = static_cast<SVGFilterElement *>(mContent);

   117     nsAutoString href;

   118     filter->mStringAttributes[SVGFilterElement::HREF].GetAnimValue(href, filter);

   119     if (href.IsEmpty()) {

   120       mNoHRefURI = true;

   121       return nullptr; // no URL

   122     }

   124     // Convert href to an nsIURI

   125     nsCOMPtr<nsIURI> targetURI;

   126     nsCOMPtr<nsIURI> base = mContent->GetBaseURI();

   127     nsContentUtils::NewURIWithDocumentCharset(getter_AddRefs(targetURI), href,

   128                                               mContent->GetCurrentDoc(), base);

   130     property =

   131       nsSVGEffects::GetPaintingProperty(targetURI, this, nsSVGEffects::HrefProperty());

   132     if (!property)

   133       return nullptr;

   134   }

   136   nsIFrame *result = property->GetReferencedFrame();

   137   if (!result)

   138     return nullptr;

   140   nsIAtom* frameType = result->GetType();

   141   if (frameType != nsGkAtoms::svgFilterFrame)

   142     return nullptr;

   144   return static_cast<nsSVGFilterFrame*>(result);

   145 }

   147 nsSVGFilterFrame *

   148 nsSVGFilterFrame::GetReferencedFilterIfNotInUse()

   149 {

   150   nsSVGFilterFrame *referenced = GetReferencedFilter();

   151   if (!referenced)

   152     return nullptr;

   154   if (referenced->mLoopFlag) {

   155     // XXXjwatt: we should really send an error to the JavaScript Console here:

   156     NS_WARNING("Filter reference loop detected while inheriting attribute!");

   157     return nullptr;

   158   }

   160   return referenced;

   161 }

   163 nsresult

   164 nsSVGFilterFrame::AttributeChanged(int32_t  aNameSpaceID,

   165                                    nsIAtom* aAttribute,

   166                                    int32_t  aModType)

   167 {

   168   if (aNameSpaceID == kNameSpaceID_None &&

   169       (aAttribute == nsGkAtoms::x ||

   170        aAttribute == nsGkAtoms::y ||

   171        aAttribute == nsGkAtoms::width ||

   172        aAttribute == nsGkAtoms::height ||

   173        aAttribute == nsGkAtoms::filterUnits ||

   174        aAttribute == nsGkAtoms::primitiveUnits)) {

   175     nsSVGEffects::InvalidateDirectRenderingObservers(this);

   176   } else if (aNameSpaceID == kNameSpaceID_XLink &&

   177              aAttribute == nsGkAtoms::href) {

   178     // Blow away our reference, if any

   179     Properties().Delete(nsSVGEffects::HrefProperty());

   180     mNoHRefURI = false;

   181     // And update whoever references us

   182     nsSVGEffects::InvalidateDirectRenderingObservers(this);

   183   }

   184   return nsSVGFilterFrameBase::AttributeChanged(aNameSpaceID,

   185                                                 aAttribute, aModType);

   186 }

   188 #ifdef DEBUG

   189 void

   190 nsSVGFilterFrame::Init(nsIContent* aContent,

   191                        nsIFrame* aParent,

   192                        nsIFrame* aPrevInFlow)

   193 {

   194   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::filter),

   195                "Content is not an SVG filter");

   197   nsSVGFilterFrameBase::Init(aContent, aParent, aPrevInFlow);

   198 }

   199 #endif /* DEBUG */

   201 nsIAtom *

   202 nsSVGFilterFrame::GetType() const

   203 {

   204   return nsGkAtoms::svgFilterFrame;

   205 }

The Tor Browser / file revision

layout/svg/nsSVGFilterFrame.cpp@97036ab72558

layout/svg/nsSVGFilterFrame.cpp