Source/WebCore/bindings/js/JSCSSStyleDeclarationCustom.cpp - WebKit - Git at Google

 /*
  * Copyright (C) 2007-2009, 2013, 2016 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 #include "config.h"
 #include "JSCSSStyleDeclarationCustom.h"

 #include "CSSParser.h"
 #include "CSSPrimitiveValue.h"
 #include "CSSPropertyNames.h"
 #include "CSSValue.h"
 #include "HashTools.h"
 #include "JSCSSValue.h"
 #include "JSNode.h"
 #include "RuntimeEnabledFeatures.h"
 #include "Settings.h"
 #include "StyleProperties.h"
 #include "StyledElement.h"
 #include <runtime/IdentifierInlines.h>
 #include <runtime/StringPrototype.h>
 #include <wtf/ASCIICType.h>
 #include <wtf/text/AtomicString.h>
 #include <wtf/text/StringConcatenate.h>
 #include <wtf/text/WTFString.h>

 using namespace JSC;

 namespace WebCore {

 void JSCSSStyleDeclaration::visitAdditionalChildren(SlotVisitor& visitor)
 {
     visitor.addOpaqueRoot(root(&wrapped()));
 }

 class CSSPropertyInfo {
 public:
     CSSPropertyID propertyID;
     bool hadPixelOrPosPrefix;
 };

 enum PropertyNamePrefix {
     PropertyNamePrefixNone,
     PropertyNamePrefixCSS,
     PropertyNamePrefixPixel,
     PropertyNamePrefixPos,
 #if ENABLE(LEGACY_CSS_VENDOR_PREFIXES)
     PropertyNamePrefixApple,
 #endif
     PropertyNamePrefixEpub,
 #if ENABLE(LEGACY_CSS_VENDOR_PREFIXES)
     PropertyNamePrefixKHTML,
 #endif
     PropertyNamePrefixWebKit
 };

 template<size_t prefixCStringLength>
 static inline bool matchesCSSPropertyNamePrefix(const StringImpl& propertyName, const char (&prefix)[prefixCStringLength])
 {
     size_t prefixLength = prefixCStringLength - 1;

     ASSERT(toASCIILower(propertyName[0]) == prefix[0]);
     const size_t offset = 1;

 #ifndef NDEBUG
     for (size_t i = 0; i < prefixLength; ++i)
         ASSERT(isASCIILower(prefix[i]));
     ASSERT(!prefix[prefixLength]);
     ASSERT(propertyName.length());
 #endif

     // The prefix within the property name must be followed by a capital letter.
     // Other characters in the prefix within the property name must be lowercase.
     if (propertyName.length() < (prefixLength + 1))
         return false;

     for (size_t i = offset; i < prefixLength; ++i) {
         if (propertyName[i] != prefix[i])
             return false;
     }

     if (!isASCIIUpper(propertyName[prefixLength]))
         return false;
     return true;
 }

 static PropertyNamePrefix getCSSPropertyNamePrefix(const StringImpl& propertyName)
 {
     ASSERT(propertyName.length());

     // First character of the prefix within the property name may be upper or lowercase.
     UChar firstChar = toASCIILower(propertyName[0]);
     switch (firstChar) {
 #if ENABLE(LEGACY_CSS_VENDOR_PREFIXES)
     case 'a':
         if (RuntimeEnabledFeatures::sharedFeatures().legacyCSSVendorPrefixesEnabled() && matchesCSSPropertyNamePrefix(propertyName, "apple"))
             return PropertyNamePrefixApple;
         break;
 #endif
     case 'c':
         if (matchesCSSPropertyNamePrefix(propertyName, "css"))
             return PropertyNamePrefixCSS;
         break;
 #if ENABLE(LEGACY_CSS_VENDOR_PREFIXES)
     case 'k':
         if (RuntimeEnabledFeatures::sharedFeatures().legacyCSSVendorPrefixesEnabled() && matchesCSSPropertyNamePrefix(propertyName, "khtml"))
             return PropertyNamePrefixKHTML;
         break;
 #endif
     case 'e':
         if (matchesCSSPropertyNamePrefix(propertyName, "epub"))
             return PropertyNamePrefixEpub;
         break;
     case 'p':
         if (matchesCSSPropertyNamePrefix(propertyName, "pos"))
             return PropertyNamePrefixPos;
         if (matchesCSSPropertyNamePrefix(propertyName, "pixel"))
             return PropertyNamePrefixPixel;
         break;
     case 'w':
         if (matchesCSSPropertyNamePrefix(propertyName, "webkit"))
             return PropertyNamePrefixWebKit;
         break;
     default:
         break;
     }
     return PropertyNamePrefixNone;
 }

 static inline void writeWebKitPrefix(char*& buffer)
 {
     *buffer++ = '-';
     *buffer++ = 'w';
     *buffer++ = 'e';
     *buffer++ = 'b';
     *buffer++ = 'k';
     *buffer++ = 'i';
     *buffer++ = 't';
     *buffer++ = '-';
 }

 static inline void writeEpubPrefix(char*& buffer)
 {
     *buffer++ = '-';
     *buffer++ = 'e';
     *buffer++ = 'p';
     *buffer++ = 'u';
     *buffer++ = 'b';
     *buffer++ = '-';
 }

 static CSSPropertyInfo cssPropertyIDForJSCSSPropertyName(PropertyName propertyName)
 {
     CSSPropertyInfo propertyInfo = {CSSPropertyInvalid, false};
     bool hadPixelOrPosPrefix = false;

     StringImpl* propertyNameString = propertyName.publicName();
     if (!propertyNameString)
         return propertyInfo;
     unsigned length = propertyNameString->length();
     if (!length)
         return propertyInfo;

     String stringForCache = String(propertyNameString);
     typedef HashMap<String, CSSPropertyInfo> CSSPropertyInfoMap;
     static NeverDestroyed<CSSPropertyInfoMap> propertyInfoCache;
     propertyInfo = propertyInfoCache.get().get(stringForCache);
     if (propertyInfo.propertyID)
         return propertyInfo;

     const size_t bufferSize = maxCSSPropertyNameLength + 1;
     char buffer[bufferSize];
     char* bufferPtr = buffer;
     const char* name = bufferPtr;

     unsigned i = 0;
     // Prefixes CSS, Pixel, Pos are ignored.
     // Prefixes Apple, KHTML and Webkit are transposed to "-webkit-".
     // The prefix "Epub" becomes "-epub-".
     switch (getCSSPropertyNamePrefix(*propertyNameString)) {
     case PropertyNamePrefixNone:
         if (isASCIIUpper((*propertyNameString)[0]))
             return propertyInfo;
         break;
     case PropertyNamePrefixCSS:
         i += 3;
         break;
     case PropertyNamePrefixPixel:
         i += 5;
         hadPixelOrPosPrefix = true;
         break;
     case PropertyNamePrefixPos:
         i += 3;
         hadPixelOrPosPrefix = true;
         break;
 #if ENABLE(LEGACY_CSS_VENDOR_PREFIXES)
     case PropertyNamePrefixApple:
     case PropertyNamePrefixKHTML:
         ASSERT(RuntimeEnabledFeatures::sharedFeatures().legacyCSSVendorPrefixesEnabled());
         writeWebKitPrefix(bufferPtr);
         i += 5;
         break;
 #endif
     case PropertyNamePrefixEpub:
         writeEpubPrefix(bufferPtr);
         i += 4;
         break;
     case PropertyNamePrefixWebKit:
         writeWebKitPrefix(bufferPtr);
         i += 6;
         break;
     }

     *bufferPtr++ = toASCIILower((*propertyNameString)[i++]);

     char* bufferEnd = buffer + bufferSize;
     char* stringEnd = bufferEnd - 1;
     size_t bufferSizeLeft = stringEnd - bufferPtr;
     size_t propertySizeLeft = length - i;
     if (propertySizeLeft > bufferSizeLeft)
         return propertyInfo;

     for (; i < length; ++i) {
         UChar c = (*propertyNameString)[i];
         if (!c || c >= 0x7F)
             return propertyInfo; // illegal character
         if (isASCIIUpper(c)) {
             size_t bufferSizeLeft = stringEnd - bufferPtr;
             size_t propertySizeLeft = length - i + 1;
             if (propertySizeLeft > bufferSizeLeft)
                 return propertyInfo;
             *bufferPtr++ = '-';
             *bufferPtr++ = toASCIILower(c);
         } else
             *bufferPtr++ = c;
         ASSERT_WITH_SECURITY_IMPLICATION(bufferPtr < bufferEnd);
     }
     ASSERT_WITH_SECURITY_IMPLICATION(bufferPtr < bufferEnd);
     *bufferPtr = '\0';

     unsigned outputLength = bufferPtr - buffer;
 #if PLATFORM(IOS)
     cssPropertyNameIOSAliasing(buffer, name, outputLength);
 #endif

     const Property* hashTableEntry = findProperty(name, outputLength);
     int propertyID = hashTableEntry ? hashTableEntry->id : 0;
     if (propertyID) {
         propertyInfo.hadPixelOrPosPrefix = hadPixelOrPosPrefix;
         propertyInfo.propertyID = static_cast<CSSPropertyID>(propertyID);
         propertyInfoCache.get().add(stringForCache, propertyInfo);
     }
     return propertyInfo;
 }

 static inline JSValue getPropertyValueFallback(ExecState* exec, JSCSSStyleDeclaration* thisObj, unsigned index)
 {
     // If the property is a shorthand property (such as "padding"),
     // it can only be accessed using getPropertyValue.
     return jsStringWithCache(exec, thisObj->wrapped().getPropertyValueInternal(static_cast<CSSPropertyID>(index)));
 }

 static inline JSValue cssPropertyGetterPixelOrPosPrefix(ExecState* exec, JSCSSStyleDeclaration* thisObj, unsigned propertyID)
 {
     // Set up pixelOrPos boolean to handle the fact that
     // pixelTop returns "CSS Top" as number value in unit pixels
     // posTop returns "CSS top" as number value in unit pixels _if_ its a
     // positioned element. if it is not a positioned element, return 0
     // from MSIE documentation FIXME: IMPLEMENT THAT (Dirk)
     RefPtr<CSSValue> v = thisObj->wrapped().getPropertyCSSValueInternal(static_cast<CSSPropertyID>(propertyID));
     if (v) {
         if (v->isPrimitiveValue())
             return jsNumber(static_pointer_cast<CSSPrimitiveValue>(v)->getFloatValue(CSSPrimitiveValue::CSS_PX));
         return jsStringOrNull(exec, v->cssText());
     }

     return getPropertyValueFallback(exec, thisObj, propertyID);
 }

 static inline JSValue cssPropertyGetter(ExecState* exec, JSCSSStyleDeclaration* thisObj, unsigned propertyID)
 {
     RefPtr<CSSValue> v = thisObj->wrapped().getPropertyCSSValueInternal(static_cast<CSSPropertyID>(propertyID));
     if (v)
         return jsStringOrNull(exec, v->cssText());

     return getPropertyValueFallback(exec, thisObj, propertyID);
 }

 bool JSCSSStyleDeclaration::getOwnPropertySlotDelegate(ExecState* exec, PropertyName propertyIdentifier, PropertySlot& slot)
 {
     CSSPropertyInfo propertyInfo = cssPropertyIDForJSCSSPropertyName(propertyIdentifier);
     if (!propertyInfo.propertyID)
         return false;

     if (propertyInfo.hadPixelOrPosPrefix)
         slot.setValue(this, DontDelete, cssPropertyGetterPixelOrPosPrefix(exec, this, propertyInfo.propertyID));
     else
         slot.setValue(this, DontDelete, cssPropertyGetter(exec, this, propertyInfo.propertyID));
     return true;
 }

 bool JSCSSStyleDeclaration::putDelegate(ExecState* exec, PropertyName propertyName, JSValue value, PutPropertySlot&, bool& putResult)
 {
     CSSPropertyInfo propertyInfo = cssPropertyIDForJSCSSPropertyName(propertyName);
     if (!propertyInfo.propertyID)
         return false;

     String propValue = valueToStringTreatingNullAsEmptyString(exec, value);
     if (propertyInfo.hadPixelOrPosPrefix)
         propValue.append("px");

     bool important = false;
     if (Settings::shouldRespectPriorityInCSSAttributeSetters()) {
         size_t importantIndex = propValue.find("!important", 0, false);
         if (importantIndex != notFound) {
             important = true;
             propValue = propValue.left(importantIndex - 1);
         }
     }

     ExceptionCode ec = 0;
     CSSPropertyID propertyID = static_cast<CSSPropertyID>(propertyInfo.propertyID);
     putResult = wrapped().setPropertyInternal(propertyID, propValue, important, ec);
     setDOMException(exec, ec);

     return true;
 }

 JSValue JSCSSStyleDeclaration::getPropertyCSSValue(ExecState& state)
 {
     VM& vm = state.vm();
     auto scope = DECLARE_THROW_SCOPE(vm);

     if (UNLIKELY(state.argumentCount() < 1))
         return throwException(&state, scope, createNotEnoughArgumentsError(&state));

     String propertyName = state.uncheckedArgument(0).toWTFString(&state);
     RETURN_IF_EXCEPTION(scope, JSValue());

     RefPtr<CSSValue> cssValue = wrapped().getPropertyCSSValue(propertyName);
     if (!cssValue)
         return jsNull();

     globalObject()->world().m_cssValueRoots.add(cssValue.get(), root(&wrapped())); // Balanced by JSCSSValueOwner::finalize().
     return toJS(&state, globalObject(), *cssValue);
 }

 void JSCSSStyleDeclaration::getOwnPropertyNames(JSObject* object, ExecState* exec, PropertyNameArray& propertyNames, EnumerationMode mode)
 {
     JSCSSStyleDeclaration* thisObject = jsCast<JSCSSStyleDeclaration*>(object);
     ASSERT_GC_OBJECT_INHERITS(thisObject, info());

     unsigned length = thisObject->wrapped().length();
     for (unsigned i = 0; i < length; ++i)
         propertyNames.add(Identifier::from(exec, i));

     static Identifier* propertyIdentifiers = 0;
     if (!propertyIdentifiers) {
         Vector<String, numCSSProperties> jsPropertyNames;
         for (int id = firstCSSProperty; id < firstCSSProperty + numCSSProperties; ++id)
             jsPropertyNames.append(getJSPropertyName(static_cast<CSSPropertyID>(id)));
         std::sort(jsPropertyNames.begin(), jsPropertyNames.end(), WTF::codePointCompareLessThan);

         propertyIdentifiers = new Identifier[numCSSProperties];
         for (int i = 0; i < numCSSProperties; ++i)
             propertyIdentifiers[i] = Identifier::fromString(exec, jsPropertyNames[i]);
     }

     for (int i = 0; i < numCSSProperties; ++i)
         propertyNames.add(propertyIdentifiers[i]);

     Base::getOwnPropertyNames(thisObject, exec, propertyNames, mode);
 }

 } // namespace WebCore
	/*
	* Copyright (C) 2007-2009, 2013, 2016 Apple Inc. All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	*
	* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
	* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
	* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
	* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
	* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
	* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	#include "config.h"
	#include "JSCSSStyleDeclarationCustom.h"

	#include "CSSParser.h"
	#include "CSSPrimitiveValue.h"
	#include "CSSPropertyNames.h"
	#include "CSSValue.h"
	#include "HashTools.h"
	#include "JSCSSValue.h"
	#include "JSNode.h"
	#include "RuntimeEnabledFeatures.h"
	#include "Settings.h"
	#include "StyleProperties.h"
	#include "StyledElement.h"
	#include <runtime/IdentifierInlines.h>
	#include <runtime/StringPrototype.h>
	#include <wtf/ASCIICType.h>
	#include <wtf/text/AtomicString.h>
	#include <wtf/text/StringConcatenate.h>
	#include <wtf/text/WTFString.h>

	using namespace JSC;

	namespace WebCore {

	void JSCSSStyleDeclaration::visitAdditionalChildren(SlotVisitor& visitor)
	{
	visitor.addOpaqueRoot(root(&wrapped()));
	}

	class CSSPropertyInfo {
	public:
	CSSPropertyID propertyID;
	bool hadPixelOrPosPrefix;
	};

	enum PropertyNamePrefix {
	PropertyNamePrefixNone,
	PropertyNamePrefixCSS,
	PropertyNamePrefixPixel,
	PropertyNamePrefixPos,
	#if ENABLE(LEGACY_CSS_VENDOR_PREFIXES)
	PropertyNamePrefixApple,
	#endif
	PropertyNamePrefixEpub,
	#if ENABLE(LEGACY_CSS_VENDOR_PREFIXES)
	PropertyNamePrefixKHTML,
	#endif
	PropertyNamePrefixWebKit
	};

	template<size_t prefixCStringLength>
	static inline bool matchesCSSPropertyNamePrefix(const StringImpl& propertyName, const char (&prefix)[prefixCStringLength])
	{
	size_t prefixLength = prefixCStringLength - 1;

	ASSERT(toASCIILower(propertyName[0]) == prefix[0]);
	const size_t offset = 1;

	#ifndef NDEBUG
	for (size_t i = 0; i < prefixLength; ++i)
	ASSERT(isASCIILower(prefix[i]));
	ASSERT(!prefix[prefixLength]);
	ASSERT(propertyName.length());
	#endif

	// The prefix within the property name must be followed by a capital letter.
	// Other characters in the prefix within the property name must be lowercase.
	if (propertyName.length() < (prefixLength + 1))
	return false;

	for (size_t i = offset; i < prefixLength; ++i) {
	if (propertyName[i] != prefix[i])
	return false;
	}

	if (!isASCIIUpper(propertyName[prefixLength]))
	return false;
	return true;
	}

	static PropertyNamePrefix getCSSPropertyNamePrefix(const StringImpl& propertyName)
	{
	ASSERT(propertyName.length());

	// First character of the prefix within the property name may be upper or lowercase.
	UChar firstChar = toASCIILower(propertyName[0]);
	switch (firstChar) {
	#if ENABLE(LEGACY_CSS_VENDOR_PREFIXES)
	case 'a':
	if (RuntimeEnabledFeatures::sharedFeatures().legacyCSSVendorPrefixesEnabled() && matchesCSSPropertyNamePrefix(propertyName, "apple"))
	return PropertyNamePrefixApple;
	break;
	#endif
	case 'c':
	if (matchesCSSPropertyNamePrefix(propertyName, "css"))
	return PropertyNamePrefixCSS;
	break;
	#if ENABLE(LEGACY_CSS_VENDOR_PREFIXES)
	case 'k':
	if (RuntimeEnabledFeatures::sharedFeatures().legacyCSSVendorPrefixesEnabled() && matchesCSSPropertyNamePrefix(propertyName, "khtml"))
	return PropertyNamePrefixKHTML;
	break;
	#endif
	case 'e':
	if (matchesCSSPropertyNamePrefix(propertyName, "epub"))
	return PropertyNamePrefixEpub;
	break;
	case 'p':
	if (matchesCSSPropertyNamePrefix(propertyName, "pos"))
	return PropertyNamePrefixPos;
	if (matchesCSSPropertyNamePrefix(propertyName, "pixel"))
	return PropertyNamePrefixPixel;
	break;
	case 'w':
	if (matchesCSSPropertyNamePrefix(propertyName, "webkit"))
	return PropertyNamePrefixWebKit;
	break;
	default:
	break;
	}
	return PropertyNamePrefixNone;
	}

	static inline void writeWebKitPrefix(char*& buffer)
	{
	*buffer++ = '-';
	*buffer++ = 'w';
	*buffer++ = 'e';
	*buffer++ = 'b';
	*buffer++ = 'k';
	*buffer++ = 'i';
	*buffer++ = 't';
	*buffer++ = '-';
	}

	static inline void writeEpubPrefix(char*& buffer)
	{
	*buffer++ = '-';
	*buffer++ = 'e';
	*buffer++ = 'p';
	*buffer++ = 'u';
	*buffer++ = 'b';
	*buffer++ = '-';
	}

	static CSSPropertyInfo cssPropertyIDForJSCSSPropertyName(PropertyName propertyName)
	{
	CSSPropertyInfo propertyInfo = {CSSPropertyInvalid, false};
	bool hadPixelOrPosPrefix = false;

	StringImpl* propertyNameString = propertyName.publicName();
	if (!propertyNameString)
	return propertyInfo;
	unsigned length = propertyNameString->length();
	if (!length)
	return propertyInfo;

	String stringForCache = String(propertyNameString);
	typedef HashMap<String, CSSPropertyInfo> CSSPropertyInfoMap;
	static NeverDestroyed<CSSPropertyInfoMap> propertyInfoCache;
	propertyInfo = propertyInfoCache.get().get(stringForCache);
	if (propertyInfo.propertyID)
	return propertyInfo;

	const size_t bufferSize = maxCSSPropertyNameLength + 1;
	char buffer[bufferSize];
	char* bufferPtr = buffer;
	const char* name = bufferPtr;

	unsigned i = 0;
	// Prefixes CSS, Pixel, Pos are ignored.
	// Prefixes Apple, KHTML and Webkit are transposed to "-webkit-".
	// The prefix "Epub" becomes "-epub-".
	switch (getCSSPropertyNamePrefix(*propertyNameString)) {
	case PropertyNamePrefixNone:
	if (isASCIIUpper((*propertyNameString)[0]))
	return propertyInfo;
	break;
	case PropertyNamePrefixCSS:
	i += 3;
	break;
	case PropertyNamePrefixPixel:
	i += 5;
	hadPixelOrPosPrefix = true;
	break;
	case PropertyNamePrefixPos:
	i += 3;
	hadPixelOrPosPrefix = true;
	break;
	#if ENABLE(LEGACY_CSS_VENDOR_PREFIXES)
	case PropertyNamePrefixApple:
	case PropertyNamePrefixKHTML:
	ASSERT(RuntimeEnabledFeatures::sharedFeatures().legacyCSSVendorPrefixesEnabled());
	writeWebKitPrefix(bufferPtr);
	i += 5;
	break;
	#endif
	case PropertyNamePrefixEpub:
	writeEpubPrefix(bufferPtr);
	i += 4;
	break;
	case PropertyNamePrefixWebKit:
	writeWebKitPrefix(bufferPtr);
	i += 6;
	break;
	}

	bufferPtr++ = toASCIILower((propertyNameString)[i++]);

	char* bufferEnd = buffer + bufferSize;
	char* stringEnd = bufferEnd - 1;
	size_t bufferSizeLeft = stringEnd - bufferPtr;
	size_t propertySizeLeft = length - i;
	if (propertySizeLeft > bufferSizeLeft)
	return propertyInfo;

	for (; i < length; ++i) {
	UChar c = (*propertyNameString)[i];
	if (!c \|\| c >= 0x7F)
	return propertyInfo; // illegal character
	if (isASCIIUpper(c)) {
	size_t bufferSizeLeft = stringEnd - bufferPtr;
	size_t propertySizeLeft = length - i + 1;
	if (propertySizeLeft > bufferSizeLeft)
	return propertyInfo;
	*bufferPtr++ = '-';
	*bufferPtr++ = toASCIILower(c);
	} else
	*bufferPtr++ = c;
	ASSERT_WITH_SECURITY_IMPLICATION(bufferPtr < bufferEnd);
	}
	ASSERT_WITH_SECURITY_IMPLICATION(bufferPtr < bufferEnd);
	*bufferPtr = '\0';

	unsigned outputLength = bufferPtr - buffer;
	#if PLATFORM(IOS)
	cssPropertyNameIOSAliasing(buffer, name, outputLength);
	#endif

	const Property* hashTableEntry = findProperty(name, outputLength);
	int propertyID = hashTableEntry ? hashTableEntry->id : 0;
	if (propertyID) {
	propertyInfo.hadPixelOrPosPrefix = hadPixelOrPosPrefix;
	propertyInfo.propertyID = static_cast<CSSPropertyID>(propertyID);
	propertyInfoCache.get().add(stringForCache, propertyInfo);
	}
	return propertyInfo;
	}

	static inline JSValue getPropertyValueFallback(ExecState* exec, JSCSSStyleDeclaration* thisObj, unsigned index)
	{
	// If the property is a shorthand property (such as "padding"),
	// it can only be accessed using getPropertyValue.
	return jsStringWithCache(exec, thisObj->wrapped().getPropertyValueInternal(static_cast<CSSPropertyID>(index)));
	}

	static inline JSValue cssPropertyGetterPixelOrPosPrefix(ExecState* exec, JSCSSStyleDeclaration* thisObj, unsigned propertyID)
	{
	// Set up pixelOrPos boolean to handle the fact that
	// pixelTop returns "CSS Top" as number value in unit pixels
	// posTop returns "CSS top" as number value in unit pixels _if_ its a
	// positioned element. if it is not a positioned element, return 0
	// from MSIE documentation FIXME: IMPLEMENT THAT (Dirk)
	RefPtr<CSSValue> v = thisObj->wrapped().getPropertyCSSValueInternal(static_cast<CSSPropertyID>(propertyID));
	if (v) {
	if (v->isPrimitiveValue())
	return jsNumber(static_pointer_cast<CSSPrimitiveValue>(v)->getFloatValue(CSSPrimitiveValue::CSS_PX));
	return jsStringOrNull(exec, v->cssText());
	}

	return getPropertyValueFallback(exec, thisObj, propertyID);
	}

	static inline JSValue cssPropertyGetter(ExecState* exec, JSCSSStyleDeclaration* thisObj, unsigned propertyID)
	{
	RefPtr<CSSValue> v = thisObj->wrapped().getPropertyCSSValueInternal(static_cast<CSSPropertyID>(propertyID));
	if (v)
	return jsStringOrNull(exec, v->cssText());

	return getPropertyValueFallback(exec, thisObj, propertyID);
	}

	bool JSCSSStyleDeclaration::getOwnPropertySlotDelegate(ExecState* exec, PropertyName propertyIdentifier, PropertySlot& slot)
	{
	CSSPropertyInfo propertyInfo = cssPropertyIDForJSCSSPropertyName(propertyIdentifier);
	if (!propertyInfo.propertyID)
	return false;

	if (propertyInfo.hadPixelOrPosPrefix)
	slot.setValue(this, DontDelete, cssPropertyGetterPixelOrPosPrefix(exec, this, propertyInfo.propertyID));
	else
	slot.setValue(this, DontDelete, cssPropertyGetter(exec, this, propertyInfo.propertyID));
	return true;
	}

	bool JSCSSStyleDeclaration::putDelegate(ExecState* exec, PropertyName propertyName, JSValue value, PutPropertySlot&, bool& putResult)
	{
	CSSPropertyInfo propertyInfo = cssPropertyIDForJSCSSPropertyName(propertyName);
	if (!propertyInfo.propertyID)
	return false;

	String propValue = valueToStringTreatingNullAsEmptyString(exec, value);
	if (propertyInfo.hadPixelOrPosPrefix)
	propValue.append("px");

	bool important = false;
	if (Settings::shouldRespectPriorityInCSSAttributeSetters()) {
	size_t importantIndex = propValue.find("!important", 0, false);
	if (importantIndex != notFound) {
	important = true;
	propValue = propValue.left(importantIndex - 1);
	}
	}

	ExceptionCode ec = 0;
	CSSPropertyID propertyID = static_cast<CSSPropertyID>(propertyInfo.propertyID);
	putResult = wrapped().setPropertyInternal(propertyID, propValue, important, ec);
	setDOMException(exec, ec);

	return true;
	}

	JSValue JSCSSStyleDeclaration::getPropertyCSSValue(ExecState& state)
	{
	VM& vm = state.vm();
	auto scope = DECLARE_THROW_SCOPE(vm);

	if (UNLIKELY(state.argumentCount() < 1))
	return throwException(&state, scope, createNotEnoughArgumentsError(&state));

	String propertyName = state.uncheckedArgument(0).toWTFString(&state);
	RETURN_IF_EXCEPTION(scope, JSValue());

	RefPtr<CSSValue> cssValue = wrapped().getPropertyCSSValue(propertyName);
	if (!cssValue)
	return jsNull();

	globalObject()->world().m_cssValueRoots.add(cssValue.get(), root(&wrapped())); // Balanced by JSCSSValueOwner::finalize().
	return toJS(&state, globalObject(), *cssValue);
	}

	void JSCSSStyleDeclaration::getOwnPropertyNames(JSObject* object, ExecState* exec, PropertyNameArray& propertyNames, EnumerationMode mode)
	{
	JSCSSStyleDeclaration* thisObject = jsCast<JSCSSStyleDeclaration*>(object);
	ASSERT_GC_OBJECT_INHERITS(thisObject, info());

	unsigned length = thisObject->wrapped().length();
	for (unsigned i = 0; i < length; ++i)
	propertyNames.add(Identifier::from(exec, i));

	static Identifier* propertyIdentifiers = 0;
	if (!propertyIdentifiers) {
	Vector<String, numCSSProperties> jsPropertyNames;
	for (int id = firstCSSProperty; id < firstCSSProperty + numCSSProperties; ++id)
	jsPropertyNames.append(getJSPropertyName(static_cast<CSSPropertyID>(id)));
	std::sort(jsPropertyNames.begin(), jsPropertyNames.end(), WTF::codePointCompareLessThan);

	propertyIdentifiers = new Identifier[numCSSProperties];
	for (int i = 0; i < numCSSProperties; ++i)
	propertyIdentifiers[i] = Identifier::fromString(exec, jsPropertyNames[i]);
	}

	for (int i = 0; i < numCSSProperties; ++i)
	propertyNames.add(propertyIdentifiers[i]);

	Base::getOwnPropertyNames(thisObject, exec, propertyNames, mode);
	}

	} // namespace WebCore