Revert 169289 "A thread-safe Media Query Parser"

trunk/Source/core/css/parser/MediaQueryTokenizer.cpp

Index: trunk/Source/core/css/parser/MediaQueryTokenizer.cpp
===================================================================
--- trunk/Source/core/css/parser/MediaQueryTokenizer.cpp	(revision 169291)
+++ trunk/Source/core/css/parser/MediaQueryTokenizer.cpp	(working copy)
@@ -1,431 +0,0 @@
-// Copyright 2014 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/parser/MediaQueryTokenizer.h"
-
-#include "core/css/parser/MediaQueryInputStream.h"
-#include "core/html/parser/HTMLParserIdioms.h"
-#include "wtf/unicode/CharacterNames.h"
-
-namespace WebCore {
-
-const unsigned codePointsNumber = SCHAR_MAX;
-
-class MediaQueryTokenizer::CodePoints {
-public:
-    MediaQueryTokenizer::CodePoint codePoints[codePointsNumber];
-
-    // FIXME: Move the codePoint array to be a static one, generated by build scripts
-    CodePoints()
-    {
-        memset(codePoints, 0, codePointsNumber);
-        codePoints['\n'] = &MediaQueryTokenizer::whiteSpace;
-        codePoints['\r'] = &MediaQueryTokenizer::whiteSpace;
-        codePoints['\t'] = &MediaQueryTokenizer::whiteSpace;
-        codePoints[' '] = &MediaQueryTokenizer::whiteSpace;
-        codePoints['\f'] = &MediaQueryTokenizer::whiteSpace;
-        codePoints['('] = &MediaQueryTokenizer::leftParenthesis;
-        codePoints[')'] = &MediaQueryTokenizer::rightParenthesis;
-        codePoints['+'] = &MediaQueryTokenizer::plusOrFullStop;
-        codePoints['.'] = &MediaQueryTokenizer::plusOrFullStop;
-        codePoints[','] = &MediaQueryTokenizer::comma;
-        codePoints['-'] = &MediaQueryTokenizer::hyphenMinus;
-        codePoints['/'] = &MediaQueryTokenizer::solidus;
-        codePoints[':'] = &MediaQueryTokenizer::colon;
-        codePoints[';'] = &MediaQueryTokenizer::semiColon;
-        codePoints['\\'] = &MediaQueryTokenizer::reverseSolidus;
-        for (unsigned char digit = '0'; digit <= '9'; ++digit)
-            codePoints[digit] = &MediaQueryTokenizer::asciiDigit;
-        for (unsigned char alpha = 'a'; alpha <= 'z'; ++alpha)
-            codePoints[alpha] = &MediaQueryTokenizer::nameStart;
-        for (unsigned char alpha = 'A'; alpha <= 'Z'; ++alpha)
-            codePoints[alpha] = &MediaQueryTokenizer::nameStart;
-        codePoints['_'] = &MediaQueryTokenizer::nameStart;
-        codePoints[kEndOfFileMarker] = &MediaQueryTokenizer::endOfFile;
-    }
-};
-
-MediaQueryTokenizer::CodePoints* MediaQueryTokenizer::codePoints()
-{
-    static CodePoints codePoints;
-    return &codePoints;
-}
-
-// http://dev.w3.org/csswg/css-syntax/#name-start-code-point
-static bool isNameStart(UChar c)
-{
-    if (isASCIIAlpha(c))
-        return true;
-    if (c == '_')
-        return true;
-    return !isASCII(c);
-}
-
-// http://www.w3.org/TR/css-syntax-3/#name-code-point
-static bool isNameChar(UChar c)
-{
-    return isNameStart(c) || isASCIIDigit(c) || c == '-';
-}
-
-// http://www.w3.org/TR/css-syntax-3/#check-if-two-code-points-are-a-valid-escape
-static bool twoCharsAreValidEscape(UChar first, UChar second)
-{
-    return ((first == '\\') && (second != '\n') && (second != kEndOfFileMarker));
-}
-
-MediaQueryTokenizer::MediaQueryTokenizer(MediaQueryInputStream& inputStream)
-    : m_input(inputStream)
-{
-}
-
-void MediaQueryTokenizer::reconsume(UChar c)
-{
-    m_input.pushBack(c);
-}
-
-UChar MediaQueryTokenizer::consume()
-{
-    UChar current = m_input.currentInputChar();
-    m_input.advance();
-    return current;
-}
-
-void MediaQueryTokenizer::consume(unsigned offset)
-{
-    m_input.advance(offset);
-}
-
-MediaQueryToken MediaQueryTokenizer::whiteSpace(UChar cc)
-{
-    // CSS Tokenization is currently lossy, but we could record
-    // the exact whitespace instead of discarding it here.
-    consumeUntilNonWhitespace();
-    return MediaQueryToken(WhitespaceToken);
-}
-
-MediaQueryToken MediaQueryTokenizer::leftParenthesis(UChar cc)
-{
-    return MediaQueryToken(LeftParenthesisToken);
-}
-
-MediaQueryToken MediaQueryTokenizer::rightParenthesis(UChar cc)
-{
-    return MediaQueryToken(RightParenthesisToken);
-}
-
-MediaQueryToken MediaQueryTokenizer::plusOrFullStop(UChar cc)
-{
-    if (nextCharsAreNumber()) {
-        reconsume(cc);
-        return consumeNumericToken();
-    }
-    return MediaQueryToken(DelimiterToken, cc);
-}
-
-MediaQueryToken MediaQueryTokenizer::comma(UChar cc)
-{
-    return MediaQueryToken(CommaToken);
-}
-
-MediaQueryToken MediaQueryTokenizer::hyphenMinus(UChar cc)
-{
-    if (nextCharsAreNumber()) {
-        reconsume(cc);
-        return consumeNumericToken();
-    }
-    if (nextCharsAreIdentifier()) {
-        reconsume(cc);
-        return consumeIdentLikeToken();
-    }
-    return MediaQueryToken(DelimiterToken, cc);
-}
-
-MediaQueryToken MediaQueryTokenizer::solidus(UChar cc)
-{
-    return MediaQueryToken(DelimiterToken, cc);
-}
-
-MediaQueryToken MediaQueryTokenizer::colon(UChar cc)
-{
-    return MediaQueryToken(ColonToken);
-}
-
-MediaQueryToken MediaQueryTokenizer::semiColon(UChar cc)
-{
-    return MediaQueryToken(SemicolonToken);
-}
-
-MediaQueryToken MediaQueryTokenizer::reverseSolidus(UChar cc)
-{
-    if (twoCharsAreValidEscape(cc, m_input.currentInputChar())) {
-        reconsume(cc);
-        return consumeIdentLikeToken();
-    }
-    return MediaQueryToken(DelimiterToken, cc);
-}
-
-MediaQueryToken MediaQueryTokenizer::asciiDigit(UChar cc)
-{
-    reconsume(cc);
-    return consumeNumericToken();
-}
-
-MediaQueryToken MediaQueryTokenizer::nameStart(UChar cc)
-{
-    reconsume(cc);
-    return consumeIdentLikeToken();
-}
-
-MediaQueryToken MediaQueryTokenizer::endOfFile(UChar cc)
-{
-    return MediaQueryToken(EOFToken);
-}
-
-void MediaQueryTokenizer::tokenize(String string, Vector<MediaQueryToken>& outTokens)
-{
-    // According to the spec, we should perform preprocessing here.
-    // See: http://www.w3.org/TR/css-syntax-3/#input-preprocessing
-    //
-    // However, we can skip this step since:
-    // * We're using HTML spaces (which accept \r and \f as a valid white space)
-    // * Do not count white spaces
-    // * consumeEscape replaces NULLs for replacement characters
-
-    MediaQueryInputStream input(string);
-    MediaQueryTokenizer tokenizer(input);
-    while (true) {
-        outTokens.append(tokenizer.nextToken());
-        if (outTokens.last().type() == EOFToken)
-            return;
-    }
-}
-
-MediaQueryToken MediaQueryTokenizer::nextToken()
-{
-    // Unlike the HTMLTokenizer, the CSS Syntax spec is written
-    // as a stateless, (fixed-size) look-ahead tokenizer.
-    // We could move to the stateful model and instead create
-    // states for all the "next 3 codepoints are X" cases.
-    // State-machine tokenizers are easier to write to handle
-    // incremental tokenization of partial sources.
-    // However, for now we follow the spec exactly.
-    UChar cc = consume();
-    CodePoint codePointFunc = 0;
-
-    if (isASCII(cc)) {
-        ASSERT_WITH_SECURITY_IMPLICATION(cc < codePointsNumber);
-        codePointFunc = codePoints()->codePoints[cc];
-    } else {
-        codePointFunc = &MediaQueryTokenizer::nameStart;
-    }
-
-    if (codePointFunc)
-        return ((this)->*(codePointFunc))(cc);
-
-    return MediaQueryToken(DelimiterToken, cc);
-}
-
-static int getSign(MediaQueryInputStream& input, unsigned& offset)
-{
-    int sign = 1;
-    if (input.currentInputChar() == '+') {
-        ++offset;
-    } else if (input.peek(offset) == '-') {
-        sign = -1;
-        ++offset;
-    }
-    return sign;
-}
-
-static unsigned long long getInteger(MediaQueryInputStream& input, unsigned& offset)
-{
-    unsigned intStartPos = offset;
-    offset = input.skipWhilePredicate<isASCIIDigit>(offset);
-    unsigned intEndPos = offset;
-    return input.getUInt(intStartPos, intEndPos);
-}
-
-static double getFraction(MediaQueryInputStream& input, unsigned& offset, unsigned& digitsNumber)
-{
-    unsigned fractionStartPos = 0;
-    unsigned fractionEndPos = 0;
-    if (input.peek(offset) == '.' && isASCIIDigit(input.peek(++offset))) {
-        fractionStartPos = offset - 1;
-        offset = input.skipWhilePredicate<isASCIIDigit>(offset);
-        fractionEndPos = offset;
-    }
-    digitsNumber = fractionEndPos- fractionStartPos;
-    return input.getDouble(fractionStartPos, fractionEndPos);
-}
-
-static unsigned long long getExponent(MediaQueryInputStream& input, unsigned& offset, int sign)
-{
-    unsigned exponentStartPos = 0;
-    unsigned exponentEndPos = 0;
-    if ((input.peek(offset) == 'E' || input.peek(offset) == 'e')) {
-        int offsetBeforeExponent = offset;
-        ++offset;
-        if (input.peek(offset) == '+') {
-            ++offset;
-        } else if (input.peek(offset) =='-') {
-            sign = -1;
-            ++offset;
-        }
-        exponentStartPos = offset;
-        offset = input.skipWhilePredicate<isASCIIDigit>(offset);
-        exponentEndPos = offset;
-        if (exponentEndPos == exponentStartPos)
-            offset = offsetBeforeExponent;
-    }
-    return input.getUInt(exponentStartPos, exponentEndPos);
-}
-
-// This method merges the following spec sections for efficiency
-// http://www.w3.org/TR/css3-syntax/#consume-a-number
-// http://www.w3.org/TR/css3-syntax/#convert-a-string-to-a-number
-MediaQueryToken MediaQueryTokenizer::consumeNumber()
-{
-    ASSERT(nextCharsAreNumber());
-    NumericValueType type = IntegerValueType;
-    double value = 0;
-    unsigned offset = 0;
-    int exponentSign = 1;
-    unsigned fractionDigits;
-    int sign = getSign(m_input, offset);
-    unsigned long long integerPart = getInteger(m_input, offset);
-    double fractionPart = getFraction(m_input, offset, fractionDigits);
-    unsigned long long exponentPart = getExponent(m_input, offset, exponentSign);
-    double exponent = pow(10, (float)exponentSign * (double)exponentPart);
-    value = (double)sign * ((double)integerPart + fractionPart) * exponent;
-
-    m_input.advance(offset);
-    if (fractionDigits > 0)
-        type = NumberValueType;
-
-    return MediaQueryToken(NumberToken, value, type);
-}
-
-// http://www.w3.org/TR/css3-syntax/#consume-a-numeric-token
-MediaQueryToken MediaQueryTokenizer::consumeNumericToken()
-{
-    MediaQueryToken token = consumeNumber();
-    if (nextCharsAreIdentifier())
-        token.convertToDimensionWithUnit(consumeName());
-    else if (consumeIfNext('%'))
-        token.convertToPercentage();
-    return token;
-}
-
-// http://www.w3.org/TR/css3-syntax/#consume-an-ident-like-token
-MediaQueryToken MediaQueryTokenizer::consumeIdentLikeToken()
-{
-    String name = consumeName();
-    if (consumeIfNext('('))
-        return MediaQueryToken(FunctionToken, name);
-    return MediaQueryToken(IdentToken, name);
-}
-
-void MediaQueryTokenizer::consumeUntilNonWhitespace()
-{
-    // Using HTML space here rather than CSS space since we don't do preprocessing
-    while (isHTMLSpace<UChar>(m_input.currentInputChar()))
-        consume();
-}
-
-bool MediaQueryTokenizer::consumeIfNext(UChar character)
-{
-    if (m_input.currentInputChar() == character) {
-        consume();
-        return true;
-    }
-    return false;
-}
-
-// http://www.w3.org/TR/css3-syntax/#consume-a-name
-String MediaQueryTokenizer::consumeName()
-{
-    // FIXME: Is this as efficient as it can be?
-    // The possibility of escape chars mandates a copy AFAICT.
-    Vector<UChar> result;
-    while (true) {
-        if (isNameChar(m_input.currentInputChar())) {
-            result.append(consume());
-            continue;
-        }
-        if (nextTwoCharsAreValidEscape()) {
-            // "consume()" fixes a spec bug.
-            // The first code point should be consumed before consuming the escaped code point.
-            consume();
-            result.append(consumeEscape());
-            continue;
-        }
-        return String(result);
-    }
-}
-
-// http://www.w3.org/TR/css-syntax-3/#consume-an-escaped-code-point
-UChar MediaQueryTokenizer::consumeEscape()
-{
-    UChar cc = consume();
-    ASSERT(cc != '\n');
-    if (isASCIIHexDigit(cc)) {
-        unsigned consumedHexDigits = 1;
-        String hexChars;
-        do {
-            hexChars.append(cc);
-            cc = consume();
-            consumedHexDigits++;
-        } while (consumedHexDigits < 6 && isASCIIHexDigit(cc));
-        bool ok = false;
-        UChar codePoint = hexChars.toUIntStrict(&ok, 16);
-        if (!ok)
-            return WTF::Unicode::replacementCharacter;
-        return codePoint;
-    }
-
-    // Replaces NULLs with replacement characters, since we do not perform preprocessing
-    if (cc == kEndOfFileMarker)
-        return WTF::Unicode::replacementCharacter;
-    return cc;
-}
-
-bool MediaQueryTokenizer::nextTwoCharsAreValidEscape()
-{
-    if (m_input.leftChars() < 2)
-        return false;
-    return twoCharsAreValidEscape(m_input.peek(1), m_input.peek(2));
-}
-
-// http://www.w3.org/TR/css3-syntax/#starts-with-a-number
-bool MediaQueryTokenizer::nextCharsAreNumber()
-{
-    UChar first = m_input.currentInputChar();
-    UChar second = m_input.peek(1);
-    if (isASCIIDigit(first))
-        return true;
-    if (first == '+' || first == '-')
-        return ((isASCIIDigit(second)) || (second == '.' && isASCIIDigit(m_input.peek(2))));
-    if (first =='.')
-        return (isASCIIDigit(second));
-    return false;
-}
-
-// http://www.w3.org/TR/css3-syntax/#would-start-an-identifier
-bool MediaQueryTokenizer::nextCharsAreIdentifier()
-{
-    UChar firstChar = m_input.currentInputChar();
-    if (isNameStart(firstChar) || nextTwoCharsAreValidEscape())
-        return true;
-
-    if (firstChar == '-') {
-        if (isNameStart(m_input.peek(1)))
-            return true;
-        return nextTwoCharsAreValidEscape();
-    }
-
-    return false;
-}
-
-} // namespace WebCore