CSS Custom Properties (Variables)

Source/core/css/CSSVariableData.cpp

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "config.h"
+#include "core/css/CSSVariableData.h"
+
+#include "core/css/parser/CSSParserTokenRange.h"
+
+namespace blink {
+
+template<typename CharacterType> void CSSVariableData::consumeAndUpdateTokens(const CSSParserTokenRange& range)
+{
+    CSSParserTokenRange localRange = range;
+    String baseString = localRange.scope()->string();
+    const CharacterType* stringStart = baseString.getCharacters<CharacterType>();
+    const CharacterType* stringEnd = stringStart + baseString.length();
+
+    const CharacterType* maxOffset = nullptr;
+    const CharacterType* minOffset = nullptr;
+
+    bool lastTokenWasExclamation = false;
+    unsigned exclamationOffset = 0;
+
+    while (!localRange.atEnd()) {
+        CSSParserToken token = localRange.consume();
+        const CharacterType* tokenLocation = static_cast<const CharacterType*>(token.m_valueDataCharRaw);
+        if (tokenLocation > stringStart && tokenLocation < stringEnd) {
+            if (!minOffset)
+                minOffset = tokenLocation;
+            maxOffset = tokenLocation + token.m_valueLength;
+        } else {
+            String escapedString(tokenLocation, token.m_valueLength);
+            m_stringPool.append(escapedString);
+            token.m_valueDataCharRaw = escapedString.getCharacters<CharacterType>();
+        }
+        if (token.type() == DelimiterToken && token.delimiter() == '!') {
+            lastTokenWasExclamation = true;
+            exclamationOffset = m_tokens.size();
+        } else if (lastTokenWasExclamation) {
+            if (token.type() == IdentToken && token.valueEqualsIgnoringCase("important")) {
+                m_important = true;
+                m_tokens.remove(exclamationOffset, m_tokens.size() - exclamationOffset);
+                lastTokenWasExclamation = false;
+                continue;
+            }
+            if (token.type() != WhitespaceToken)
+                lastTokenWasExclamation = false;
+        }
+        m_tokens.append(token);
+    }
+    if (minOffset) {
+        m_string = String(minOffset, maxOffset - minOffset);
+        const CharacterType* newStringStart = m_string.getCharacters<CharacterType>();
+        for (CSSParserToken& token : m_tokens) {
+            const CharacterType* tokenLocation = static_cast<const CharacterType*>(token.m_valueDataCharRaw);
+            if (tokenLocation > stringStart && tokenLocation < stringEnd)
+                token.m_valueDataCharRaw = newStringStart + (tokenLocation - minOffset);
+        }
+    }
+}
+
+CSSVariableData::CSSVariableData(const CSSParserTokenRange& range, bool needsVariableResolution)
+    : m_needsVariableResolution(needsVariableResolution)
+{
+    if (range.scope()->string().is8Bit())
+        consumeAndUpdateTokens<LChar>(range);
+    else
+        consumeAndUpdateTokens<UChar>(range);
+}
+
+} // namespace blink