CSS Custom Properties (Variables)

Source/core/css/parser/CSSParserValues.cpp

 /*
  * Copyright (C) 2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2008 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  */
 
 #include "config.h"
 #include "core/css/parser/CSSParserValues.h"
 
 #include "core/css/CSSFunctionValue.h"
 #include "core/css/CSSSelectorList.h"
+#include "core/css/CSSVariableData.h"
 #include "core/css/parser/CSSParserToken.h"
 #include "core/css/parser/CSSParserTokenRange.h"
 #include "core/css/parser/CSSPropertyParser.h"
+#include "core/css/parser/CSSTokenizer.h"
+#include "core/css/parser/CSSVariableParser.h"
 #include "core/html/parser/HTMLParserIdioms.h"
+#include "wtf/text/StringBuilder.h"
 
 namespace blink {
 
 using namespace WTF;
 
-CSSParserValueList::CSSParserValueList(CSSParserTokenRange range, bool& usesRemUnits)
+struct SameSizeAsCSSParserValue {
+    CSSValueID id;
+    CSSParserString valueUnion;
+    int unit;
+};
+
+static_assert(sizeof(CSSParserValue) == sizeof(SameSizeAsCSSParserValue), "CSSParserValue should stay small");
+
+CSSParserValueList::CSSParserValueList(CSSParserTokenRange range, bool& usesRemUnits, bool& usesVariables)
 : m_current(0)
 {
-    usesRemUnits = false;
+    CSSParserTokenRange originalRangeForVariables = range;
+
+    usesRemUnits = usesVariables = false;
     Vector<CSSParserValueList*> stack;
     Vector<int> bracketCounts;
     stack.append(this);
     bracketCounts.append(0);
     unsigned calcDepth = 0;
     while (!range.atEnd()) {
         ASSERT(stack.size() == bracketCounts.size());
         ASSERT(!stack.isEmpty());
         const CSSParserToken& token = range.consume();
         CSSParserValue value;
         switch (token.type()) {
         case FunctionToken: {
             if (token.valueEqualsIgnoringCase("url")) {
                 const CSSParserToken& next = range.consumeIncludingWhitespace();
                 if (next.type() == BadStringToken || range.consume().type() != RightParenthesisToken) {
-                    destroyAndClear();
+                    checkForVariableReferencesOrDestroyAndClear(originalRangeForVariables);
                     return;
                 }
                 ASSERT(next.type() == StringToken);
                 value.id = CSSValueInvalid;
                 value.isInt = false;
                 value.unit = CSSPrimitiveValue::CSS_URI;
                 value.string = next.value();
                 break;
+            } else if (token.valueEqualsIgnoringCase("var")) {
+                checkForVariableReferencesOrDestroyAndClear(originalRangeForVariables);
+                return;
             }
 
             CSSParserFunction* function = new CSSParserFunction;
             function->id = cssValueKeywordID(token.value());
             CSSParserValueList* list = new CSSParserValueList;
             function->args = adoptPtr(list);
 
             value.id = CSSValueInvalid;
             value.isInt = false;
             value.unit = CSSParserValue::Function;
             value.function = function;
 
             stack.last()->addValue(value);
             stack.append(list);
             bracketCounts.append(0);
             calcDepth += (function->id == CSSValueCalc || function->id == CSSValueWebkitCalc);
+            if (function->id == CSSValueVar)
+                usesVariables = true;
             continue;
         }
         case LeftParenthesisToken: {
             if (calcDepth == 0) {
                 CSSParserValueList* list = new CSSParserValueList;
                 value.setFromValueList(adoptPtr(list));
                 stack.last()->addValue(value);
                 stack.append(list);
                 bracketCounts.append(0);
                 continue;
             }
             bracketCounts.last()++;
             value.setFromOperator('(');
             break;
         }
         case RightParenthesisToken: {
             if (bracketCounts.last() == 0) {
                 stack.removeLast();
                 bracketCounts.removeLast();
                 if (bracketCounts.isEmpty()) {
-                    destroyAndClear();
+                    checkForVariableReferencesOrDestroyAndClear(originalRangeForVariables);
                     return;
                 }
                 CSSParserValueList* currentList = stack.last();
                 CSSParserValue* current = currentList->valueAt(currentList->size()-1);
                 if (current->unit == CSSParserValue::Function) {
                     CSSValueID id = current->function->id;
                     calcDepth -= (id == CSSValueCalc || id == CSSValueWebkitCalc);
                 }
                 continue;
             }
@@ skipping 54 matching lines @@
         case UnicodeRangeToken: {
             value.id = CSSValueInvalid;
             value.isInt = false;
             value.m_unicodeRange.start = token.unicodeRangeStart();
             value.m_unicodeRange.end = token.unicodeRangeEnd();
             value.unit = CSSParserValue::UnicodeRange;
             break;
         }
         case HashToken:
         case StringToken:
+        case VariableReferenceToken:
         case UrlToken: {
             value.id = CSSValueInvalid;
             value.isInt = false;
             if (token.type() == HashToken)
                 value.unit = CSSParserValue::HexColor;
             else if (token.type() == StringToken)
                 value.unit = CSSPrimitiveValue::CSS_STRING;
             else
                 value.unit = CSSPrimitiveValue::CSS_URI;
             value.string = token.value();
             break;
         }
         case DelimiterToken:
             value.setFromOperator(token.delimiter());
             if (calcDepth && token.delimiter() == '+' && (&token - 1)->type() != WhitespaceToken) {
                 // calc(1px+ 2px) is invalid
-                destroyAndClear();
+                checkForVariableReferencesOrDestroyAndClear(originalRangeForVariables);
                 return;
             }
             break;
         case CommaToken:
             value.setFromOperator(',');
             break;
         case LeftBracketToken:
             value.setFromOperator('[');
             break;
         case RightBracketToken:
@@ skipping 43 matching lines @@
 
 static void destroy(Vector<CSSParserValue, 4>& values)
 {
     size_t numValues = values.size();
     for (size_t i = 0; i < numValues; i++) {
         if (values[i].unit == CSSParserValue::Function)
             delete values[i].function;
         else if (values[i].unit == CSSParserValue::ValueList
             || values[i].unit == CSSParserValue::DimensionList)
             delete values[i].valueList;
+        else if (values[i].unit == CSSParserValue::VariableValue)
+            values[i].variableData->deref();
     }
 }
 
+void CSSParserValueList::checkForVariableReferencesOrDestroyAndClear(const CSSParserTokenRange& originalRange)
+{
+    // We have to clear any state that may have been previously loaded
+    destroyAndClear();
+    if (CSSVariableParser::containsValidVariableReferences(originalRange))
+        consumeVariableValue(originalRange);
+}
+
+void CSSParserValueList::consumeVariableValue(const CSSParserTokenRange& originalRange)
+{
+    ASSERT(m_values.isEmpty());
+    CSSParserValue variableValue;
+    variableValue.id = CSSValueInternalVariableValue;
+    variableValue.isInt = false;
+    variableValue.unit = CSSParserValue::VariableValue;
+    variableValue.variableData = CSSVariableData::create(originalRange).leakRef();
+    addValue(variableValue);
+}
+
 void CSSParserValueList::destroyAndClear()
 {
     destroy(m_values);
     clearAndLeakValues();
 }
 
 CSSParserValueList::~CSSParserValueList()
 {
     destroy(m_values);
 }
@@ skipping 90 matching lines @@
 bool CSSParserSelector::hasHostPseudoSelector() const
 {
     for (CSSParserSelector* selector = const_cast<CSSParserSelector*>(this); selector; selector = selector->tagHistory()) {
         if (selector->pseudoType() == CSSSelector::PseudoHost || selector->pseudoType() == CSSSelector::PseudoHostContext)
             return true;
     }
     return false;
 }
 
 } // namespace blink