The Tor Browser: dom/smil/nsSMILCSSValueType.cpp@97036ab72558 (annotated)

dom/smil/nsSMILCSSValueType.cpp@97036ab72558 (annotated)

dom/smil/nsSMILCSSValueType.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/. */
 /* representation of a value for a SMIL-animated CSS property */
 #include "nsSMILCSSValueType.h"
 #include "nsString.h"
 #include "nsStyleAnimation.h"
 #include "nsSMILParserUtils.h"
 #include "nsSMILValue.h"
 #include "nsCSSValue.h"
 #include "nsColor.h"
 #include "nsPresContext.h"
 #include "mozilla/dom/Element.h"
 #include "nsDebug.h"
 #include "nsStyleUtil.h"
 #include "nsIDocument.h"
 using namespace mozilla::dom;
 /*static*/ nsSMILCSSValueType nsSMILCSSValueType::sSingleton;
 struct ValueWrapper {
   ValueWrapper(nsCSSProperty aPropID, const nsStyleAnimation::Value& aValue) :
     mPropID(aPropID), mCSSValue(aValue) {}
   nsCSSProperty mPropID;
   nsStyleAnimation::Value mCSSValue;
 };
 // Helper Methods
 // --------------
 static const nsStyleAnimation::Value*
 GetZeroValueForUnit(nsStyleAnimation::Unit aUnit)
 {
   static const nsStyleAnimation::Value
     sZeroCoord(0, nsStyleAnimation::Value::CoordConstructor);
   static const nsStyleAnimation::Value
     sZeroPercent(0.0f, nsStyleAnimation::Value::PercentConstructor);
   static const nsStyleAnimation::Value
     sZeroFloat(0.0f,  nsStyleAnimation::Value::FloatConstructor);
   static const nsStyleAnimation::Value
     sZeroColor(NS_RGB(0,0,0), nsStyleAnimation::Value::ColorConstructor);
   NS_ABORT_IF_FALSE(aUnit != nsStyleAnimation::eUnit_Null,
                     "Need non-null unit for a zero value");
   switch (aUnit) {
     case nsStyleAnimation::eUnit_Coord:
       return &sZeroCoord;
     case nsStyleAnimation::eUnit_Percent:
       return &sZeroPercent;
     case nsStyleAnimation::eUnit_Float:
       return &sZeroFloat;
     case nsStyleAnimation::eUnit_Color:
       return &sZeroColor;
     default:
       return nullptr;
   }
 }
 // This method requires at least one of its arguments to be non-null.
 //
 // If one argument is null, this method updates it to point to "zero"
 // for the other argument's Unit (if applicable; otherwise, we return false).
 //
 // If neither argument is null, this method generally does nothing, though it
 // may apply a workaround for the special case where a 0 length-value is mixed
 // with a eUnit_Float value.  (See comment below.)
 //
 // Returns true on success, or false.
 static const bool
 FinalizeStyleAnimationValues(const nsStyleAnimation::Value*& aValue1,
                              const nsStyleAnimation::Value*& aValue2)
 {
   NS_ABORT_IF_FALSE(aValue1 || aValue2,
                     "expecting at least one non-null value");
   // Are we missing either val? (If so, it's an implied 0 in other val's units)
   if (!aValue1) {
     aValue1 = GetZeroValueForUnit(aValue2->GetUnit());
     return !!aValue1; // Fail if we have no zero value for this unit.
   }
   if (!aValue2) {
     aValue2 = GetZeroValueForUnit(aValue1->GetUnit());
     return !!aValue2; // Fail if we have no zero value for this unit.
   }
   // Ok, both values were specified.
   // Need to handle a special-case, though: unitless nonzero length (parsed as
   // eUnit_Float) mixed with unitless 0 length (parsed as eUnit_Coord).  These
   // won't interoperate in nsStyleAnimation, since their Units don't match.
   // In this case, we replace the eUnit_Coord 0 value with eUnit_Float 0 value.
   const nsStyleAnimation::Value& zeroCoord =
     *GetZeroValueForUnit(nsStyleAnimation::eUnit_Coord);
   if (*aValue1 == zeroCoord &&
       aValue2->GetUnit() == nsStyleAnimation::eUnit_Float) {
     aValue1 = GetZeroValueForUnit(nsStyleAnimation::eUnit_Float);
   } else if (*aValue2 == zeroCoord &&
              aValue1->GetUnit() == nsStyleAnimation::eUnit_Float) {
     aValue2 = GetZeroValueForUnit(nsStyleAnimation::eUnit_Float);
   }
   return true;
 }
 static void
 InvertSign(nsStyleAnimation::Value& aValue)
 {
   switch (aValue.GetUnit()) {
     case nsStyleAnimation::eUnit_Coord:
       aValue.SetCoordValue(-aValue.GetCoordValue());
       break;
     case nsStyleAnimation::eUnit_Percent:
       aValue.SetPercentValue(-aValue.GetPercentValue());
       break;
     case nsStyleAnimation::eUnit_Float:
       aValue.SetFloatValue(-aValue.GetFloatValue());
       break;
     default:
       NS_NOTREACHED("Calling InvertSign with an unsupported unit");
       break;
   }
 }
 static ValueWrapper*
 ExtractValueWrapper(nsSMILValue& aValue)
 {
   return static_cast<ValueWrapper*>(aValue.mU.mPtr);
 }
 static const ValueWrapper*
 ExtractValueWrapper(const nsSMILValue& aValue)
 {
   return static_cast<const ValueWrapper*>(aValue.mU.mPtr);
 }
 // Class methods
 // -------------
 void
 nsSMILCSSValueType::Init(nsSMILValue& aValue) const
 {
   NS_ABORT_IF_FALSE(aValue.IsNull(), "Unexpected SMIL value type");
   aValue.mU.mPtr = nullptr;
   aValue.mType = this;
 }
 void
 nsSMILCSSValueType::Destroy(nsSMILValue& aValue) const
 {
   NS_ABORT_IF_FALSE(aValue.mType == this, "Unexpected SMIL value type");
   delete static_cast<ValueWrapper*>(aValue.mU.mPtr);
   aValue.mType = nsSMILNullType::Singleton();
 }
 nsresult
 nsSMILCSSValueType::Assign(nsSMILValue& aDest, const nsSMILValue& aSrc) const
 {
   NS_ABORT_IF_FALSE(aDest.mType == aSrc.mType, "Incompatible SMIL types");
   NS_ABORT_IF_FALSE(aDest.mType == this, "Unexpected SMIL value type");
   const ValueWrapper* srcWrapper = ExtractValueWrapper(aSrc);
   ValueWrapper* destWrapper = ExtractValueWrapper(aDest);
   if (srcWrapper) {
     if (!destWrapper) {
       // barely-initialized dest -- need to alloc & copy
       aDest.mU.mPtr = new ValueWrapper(*srcWrapper);
     } else {
       // both already fully-initialized -- just copy straight across
       *destWrapper = *srcWrapper;
     }
   } else if (destWrapper) {
     // fully-initialized dest, barely-initialized src -- clear dest
     delete destWrapper;
     aDest.mU.mPtr = destWrapper = nullptr;
   } // else, both are barely-initialized -- nothing to do.
   return NS_OK;
 }
 bool
 nsSMILCSSValueType::IsEqual(const nsSMILValue& aLeft,
                             const nsSMILValue& aRight) const
 {
   NS_ABORT_IF_FALSE(aLeft.mType == aRight.mType, "Incompatible SMIL types");
   NS_ABORT_IF_FALSE(aLeft.mType == this, "Unexpected SMIL value");
   const ValueWrapper* leftWrapper = ExtractValueWrapper(aLeft);
   const ValueWrapper* rightWrapper = ExtractValueWrapper(aRight);
   if (leftWrapper) {
     if (rightWrapper) {
       // Both non-null
       NS_WARN_IF_FALSE(leftWrapper != rightWrapper,
                        "Two nsSMILValues with matching ValueWrapper ptr");
       return (leftWrapper->mPropID == rightWrapper->mPropID &&
               leftWrapper->mCSSValue == rightWrapper->mCSSValue);
     }
     // Left non-null, right null
     return false;
   }
   if (rightWrapper) {
     // Left null, right non-null
     return false;
   }
   // Both null
   return true;
 }
 nsresult
 nsSMILCSSValueType::Add(nsSMILValue& aDest, const nsSMILValue& aValueToAdd,
                         uint32_t aCount) const
 {
   NS_ABORT_IF_FALSE(aValueToAdd.mType == aDest.mType,
                     "Trying to add invalid types");
   NS_ABORT_IF_FALSE(aValueToAdd.mType == this, "Unexpected source type");
   ValueWrapper* destWrapper = ExtractValueWrapper(aDest);
   const ValueWrapper* valueToAddWrapper = ExtractValueWrapper(aValueToAdd);
   NS_ABORT_IF_FALSE(destWrapper || valueToAddWrapper,
                     "need at least one fully-initialized value");
   nsCSSProperty property = (valueToAddWrapper ? valueToAddWrapper->mPropID :
                             destWrapper->mPropID);
   // Special case: font-size-adjust and stroke-dasharray are explicitly
   // non-additive (even though nsStyleAnimation *could* support adding them)
   if (property == eCSSProperty_font_size_adjust ||
       property == eCSSProperty_stroke_dasharray) {
     return NS_ERROR_FAILURE;
   }
   const nsStyleAnimation::Value* valueToAdd = valueToAddWrapper ?
     &valueToAddWrapper->mCSSValue : nullptr;
   const nsStyleAnimation::Value* destValue = destWrapper ?
     &destWrapper->mCSSValue : nullptr;
   if (!FinalizeStyleAnimationValues(valueToAdd, destValue)) {
     return NS_ERROR_FAILURE;
   }
   // Did FinalizeStyleAnimationValues change destValue?
   // If so, update outparam to use the new value.
   if (destWrapper && &destWrapper->mCSSValue != destValue) {
     destWrapper->mCSSValue = *destValue;
   }
   // Handle barely-initialized "zero" destination.
   if (!destWrapper) {
     aDest.mU.mPtr = destWrapper =
       new ValueWrapper(property, *destValue);
   }
   return nsStyleAnimation::Add(property,
                                destWrapper->mCSSValue, *valueToAdd, aCount) ?
     NS_OK : NS_ERROR_FAILURE;
 }
 nsresult
 nsSMILCSSValueType::ComputeDistance(const nsSMILValue& aFrom,
                                     const nsSMILValue& aTo,
                                     double& aDistance) const
 {
   NS_ABORT_IF_FALSE(aFrom.mType == aTo.mType,
                     "Trying to compare different types");
   NS_ABORT_IF_FALSE(aFrom.mType == this, "Unexpected source type");
   const ValueWrapper* fromWrapper = ExtractValueWrapper(aFrom);
   const ValueWrapper* toWrapper = ExtractValueWrapper(aTo);
   NS_ABORT_IF_FALSE(toWrapper, "expecting non-null endpoint");
   const nsStyleAnimation::Value* fromCSSValue = fromWrapper ?
     &fromWrapper->mCSSValue : nullptr;
   const nsStyleAnimation::Value* toCSSValue = &toWrapper->mCSSValue;
   if (!FinalizeStyleAnimationValues(fromCSSValue, toCSSValue)) {
     return NS_ERROR_FAILURE;
   }
   return nsStyleAnimation::ComputeDistance(toWrapper->mPropID,
                                            *fromCSSValue, *toCSSValue,
                                            aDistance) ?
     NS_OK : NS_ERROR_FAILURE;
 }
 nsresult
 nsSMILCSSValueType::Interpolate(const nsSMILValue& aStartVal,
                                 const nsSMILValue& aEndVal,
                                 double aUnitDistance,
                                 nsSMILValue& aResult) const
 {
   NS_ABORT_IF_FALSE(aStartVal.mType == aEndVal.mType,
                     "Trying to interpolate different types");
   NS_ABORT_IF_FALSE(aStartVal.mType == this,
                     "Unexpected types for interpolation");
   NS_ABORT_IF_FALSE(aResult.mType == this, "Unexpected result type");
   NS_ABORT_IF_FALSE(aUnitDistance >= 0.0 && aUnitDistance <= 1.0,
                     "unit distance value out of bounds");
   NS_ABORT_IF_FALSE(!aResult.mU.mPtr, "expecting barely-initialized outparam");
   const ValueWrapper* startWrapper = ExtractValueWrapper(aStartVal);
   const ValueWrapper* endWrapper = ExtractValueWrapper(aEndVal);
   NS_ABORT_IF_FALSE(endWrapper, "expecting non-null endpoint");
   const nsStyleAnimation::Value* startCSSValue = startWrapper ?
     &startWrapper->mCSSValue : nullptr;
   const nsStyleAnimation::Value* endCSSValue = &endWrapper->mCSSValue;
   if (!FinalizeStyleAnimationValues(startCSSValue, endCSSValue)) {
     return NS_ERROR_FAILURE;
   }
   nsStyleAnimation::Value resultValue;
   if (nsStyleAnimation::Interpolate(endWrapper->mPropID,
                                     *startCSSValue, *endCSSValue,
                                     aUnitDistance, resultValue)) {
     aResult.mU.mPtr = new ValueWrapper(endWrapper->mPropID, resultValue);
     return NS_OK;
   }
   return NS_ERROR_FAILURE;
 }
 // Helper function to extract presContext
 static nsPresContext*
 GetPresContextForElement(Element* aElem)
 {
   nsIDocument* doc = aElem->GetCurrentDoc();
   if (!doc) {
     // This can happen if we process certain types of restyles mid-sample
     // and remove anonymous animated content from the document as a result.
     // See bug 534975.
     return nullptr;
   }
   nsIPresShell* shell = doc->GetShell();
   return shell ? shell->GetPresContext() : nullptr;
 }
 // Helper function to parse a string into a nsStyleAnimation::Value
 static bool
 ValueFromStringHelper(nsCSSProperty aPropID,
                       Element* aTargetElement,
                       nsPresContext* aPresContext,
                       const nsAString& aString,
                       nsStyleAnimation::Value& aStyleAnimValue,
                       bool* aIsContextSensitive)
 {
   // If value is negative, we'll strip off the "-" so the CSS parser won't
   // barf, and then manually make the parsed value negative.
   // (This is a partial solution to let us accept some otherwise out-of-bounds
   // CSS values. Bug 501188 will provide a more complete fix.)
   bool isNegative = false;
   uint32_t subStringBegin = 0;
   // NOTE: We need to opt-out 'stroke-dasharray' from the negative-number
   // check.  Its values might look negative (e.g. by starting with "-1"), but
   // they're more complicated than our simple negation logic here can handle.
   if (aPropID != eCSSProperty_stroke_dasharray) {
     int32_t absValuePos = nsSMILParserUtils::CheckForNegativeNumber(aString);
     if (absValuePos > 0) {
       isNegative = true;
       subStringBegin = (uint32_t)absValuePos; // Start parsing after '-' sign
     }
   }
   nsDependentSubstring subString(aString, subStringBegin);
   if (!nsStyleAnimation::ComputeValue(aPropID, aTargetElement, subString,
                                       true, aStyleAnimValue,
                                       aIsContextSensitive)) {
     return false;
   }
   if (isNegative) {
     InvertSign(aStyleAnimValue);
   }
   if (aPropID == eCSSProperty_font_size) {
     // Divide out text-zoom, since SVG is supposed to ignore it
     NS_ABORT_IF_FALSE(aStyleAnimValue.GetUnit() ==
                         nsStyleAnimation::eUnit_Coord,
                       "'font-size' value with unexpected style unit");
     aStyleAnimValue.SetCoordValue(aStyleAnimValue.GetCoordValue() /
                                   aPresContext->TextZoom());
   }
   return true;
 }
 // static
 void
 nsSMILCSSValueType::ValueFromString(nsCSSProperty aPropID,
                                     Element* aTargetElement,
                                     const nsAString& aString,
                                     nsSMILValue& aValue,
                                     bool* aIsContextSensitive)
 {
   NS_ABORT_IF_FALSE(aValue.IsNull(), "Outparam should be null-typed");
   nsPresContext* presContext = GetPresContextForElement(aTargetElement);
   if (!presContext) {
     NS_WARNING("Not parsing animation value; unable to get PresContext");
     return;
   }
   nsIDocument* doc = aTargetElement->GetCurrentDoc();
   if (doc && !nsStyleUtil::CSPAllowsInlineStyle(nullptr,
                                                 doc->NodePrincipal(),
                                                 doc->GetDocumentURI(),
 , aString, nullptr)) {
     return;
   }
   nsStyleAnimation::Value parsedValue;
   if (ValueFromStringHelper(aPropID, aTargetElement, presContext,
                             aString, parsedValue, aIsContextSensitive)) {
     sSingleton.Init(aValue);
     aValue.mU.mPtr = new ValueWrapper(aPropID, parsedValue);
   }
 }
 // static
 bool
 nsSMILCSSValueType::ValueToString(const nsSMILValue& aValue,
                                   nsAString& aString)
 {
   NS_ABORT_IF_FALSE(aValue.mType == &nsSMILCSSValueType::sSingleton,
                     "Unexpected SMIL value type");
   const ValueWrapper* wrapper = ExtractValueWrapper(aValue);
   return !wrapper ||
     nsStyleAnimation::UncomputeValue(wrapper->mPropID,
                                      wrapper->mCSSValue, aString);
 }

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dom/smil/nsSMILCSSValueType.cpp@97036ab72558 (annotated)

dom/smil/nsSMILCSSValueType.cpp