cssparser.cpp

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        deleteFontFaceOnlyValues();
    if (m_numParsedProperties) {
        ok = true;
        declaration->addParsedProperties(m_parsedProperties, m_numParsedProperties);
        clearProperties();
    }

    return ok;
}

bool CSSParser::parseMediaQuery(MediaList* queries, const String& string)
{
    if (string.isEmpty())
        return true;

    m_mediaQuery = 0;
    // can't use { because tokenizer state switches from mediaquery to initial state when it sees { token.
    // instead insert one " " (which is WHITESPACE in CSSGrammar.y)
    setupParser ("@-webkit-mediaquery ", string, "} ");
    cssyyparse(this);

    bool ok = false;
    if (m_mediaQuery) {
        ok = true;
        queries->appendMediaQuery(m_mediaQuery);
        m_mediaQuery = 0;
    }

    return ok;
}


void CSSParser::addProperty(int propId, PassRefPtr<CSSValue> value, bool important)
{
    CSSProperty* prop = new CSSProperty(propId, value, important, m_currentShorthand, m_implicitShorthand);
    if (m_numParsedProperties >= m_maxParsedProperties) {
        m_maxParsedProperties += 32;
        if (m_maxParsedProperties > UINT_MAX / sizeof(CSSProperty*))
            return;
        m_parsedProperties = static_cast<CSSProperty**>(fastRealloc(m_parsedProperties,
                                                       m_maxParsedProperties * sizeof(CSSProperty*)));
    }
    m_parsedProperties[m_numParsedProperties++] = prop;
}

void CSSParser::rollbackLastProperties(int num)
{
    ASSERT(num >= 0);
    ASSERT(m_numParsedProperties >= static_cast<unsigned>(num));

    for (int i = 0; i < num; ++i)
        delete m_parsedProperties[--m_numParsedProperties];
}

void CSSParser::clearProperties()
{
    for (unsigned i = 0; i < m_numParsedProperties; i++)
        delete m_parsedProperties[i];
    m_numParsedProperties = 0;
    m_hasFontFaceOnlyValues = false;
}

Document* CSSParser::document() const
{
    StyleBase* root = m_styleSheet;
    Document* doc = 0;
    while (root && root->parent())
        root = root->parent();
    if (root && root->isCSSStyleSheet())
        doc = static_cast<CSSStyleSheet*>(root)->doc();
    return doc;
}

bool CSSParser::validUnit(CSSParserValue* value, Units unitflags, bool strict)
{
    if (unitflags & FNonNeg && value->fValue < 0)
        return false;

    bool b = false;
    switch(value->unit) {
    case CSSPrimitiveValue::CSS_NUMBER:
        b = (unitflags & FNumber);
        if (!b && ((unitflags & (FLength | FAngle | FTime)) && (value->fValue == 0 || !strict))) {
            value->unit = (unitflags & FLength) ? CSSPrimitiveValue::CSS_PX :
                          ((unitflags & FAngle) ? CSSPrimitiveValue::CSS_DEG : CSSPrimitiveValue::CSS_MS);
            b = true;
        }
        if (!b && (unitflags & FInteger) && value->isInt)
            b = true;
        break;
    case CSSPrimitiveValue::CSS_PERCENTAGE:
        b = (unitflags & FPercent);
        break;
    case CSSParserValue::Q_EMS:
    case CSSPrimitiveValue::CSS_EMS:
    case CSSPrimitiveValue::CSS_EXS:
    case CSSPrimitiveValue::CSS_PX:
    case CSSPrimitiveValue::CSS_CM:
    case CSSPrimitiveValue::CSS_MM:
    case CSSPrimitiveValue::CSS_IN:
    case CSSPrimitiveValue::CSS_PT:
    case CSSPrimitiveValue::CSS_PC:
        b = (unitflags & FLength);
        break;
    case CSSPrimitiveValue::CSS_MS:
    case CSSPrimitiveValue::CSS_S:
        b = (unitflags & FTime);
        break;
    case CSSPrimitiveValue::CSS_DEG:
    case CSSPrimitiveValue::CSS_RAD:
    case CSSPrimitiveValue::CSS_GRAD:
    case CSSPrimitiveValue::CSS_TURN:
        b = (unitflags & FAngle);
        break;
    case CSSPrimitiveValue::CSS_HZ:
    case CSSPrimitiveValue::CSS_KHZ:
    case CSSPrimitiveValue::CSS_DIMENSION:
    default:
        break;
    }
    return b;
}

static int unitFromString(CSSParserValue* value)
{
    if (value->unit != CSSPrimitiveValue::CSS_IDENT || value->id)
        return 0;

    if (equal(value->string, "em"))
        return CSSPrimitiveValue::CSS_EMS;
    if (equal(value->string, "ex"))
        return CSSPrimitiveValue::CSS_EXS;
    if (equal(value->string, "px"))
        return CSSPrimitiveValue::CSS_PX;
    if (equal(value->string, "cm"))
        return CSSPrimitiveValue::CSS_CM;
    if (equal(value->string, "mm"))
        return CSSPrimitiveValue::CSS_MM;
    if (equal(value->string, "in"))
        return CSSPrimitiveValue::CSS_IN;
    if (equal(value->string, "pt"))
        return CSSPrimitiveValue::CSS_PT;
    if (equal(value->string, "pc"))
        return CSSPrimitiveValue::CSS_PC;
    if (equal(value->string, "deg"))
        return CSSPrimitiveValue::CSS_DEG;
    if (equal(value->string, "rad"))
        return CSSPrimitiveValue::CSS_RAD;
    if (equal(value->string, "grad"))
        return CSSPrimitiveValue::CSS_GRAD;
    if (equal(value->string, "turn"))
        return CSSPrimitiveValue::CSS_TURN;
    if (equal(value->string, "ms"))
        return CSSPrimitiveValue::CSS_MS;
    if (equal(value->string, "s"))
        return CSSPrimitiveValue::CSS_S;
    if (equal(value->string, "Hz"))
        return CSSPrimitiveValue::CSS_HZ;
    if (equal(value->string, "kHz"))
        return CSSPrimitiveValue::CSS_KHZ;
    
    return 0;
}

void CSSParser::checkForOrphanedUnits()
{
    if (m_strict || inShorthand())
        return;
        
    // The purpose of this code is to implement the WinIE quirk that allows unit types to be separated from their numeric values
    // by whitespace, so e.g., width: 20 px instead of width:20px.  This is invalid CSS, so we don't do this in strict mode.
    CSSParserValue* numericVal = 0;
    unsigned size = m_valueList->size();
    for (unsigned i = 0; i < size; i++) {
        CSSParserValue* value = m_valueList->valueAt(i);

        if (numericVal) {
            // Change the unit type of the numeric val to match.
            int unit = unitFromString(value);
            if (unit) {
                numericVal->unit = unit;
                numericVal = 0;

                // Now delete the bogus unit value.
                m_valueList->deleteValueAt(i);
                i--; // We're safe even though |i| is unsigned, since we only hit this code if we had a previous numeric value (so |i| is always > 0 here).
                size--;
                continue;
            }
        }
        
        numericVal = (value->unit == CSSPrimitiveValue::CSS_NUMBER) ? value : 0;
    }
}

bool CSSParser::parseValue(int propId, bool important)
{
    if (!m_valueList)
        return false;

    CSSParserValue *value = m_valueList->current();

    if (!value)
        return false;

    int id = value->id;

    // In quirks mode, we will look for units that have been incorrectly separated from the number they belong to
    // by a space.  We go ahead and associate the unit with the number even though it is invalid CSS.
    checkForOrphanedUnits();
    
    int num = inShorthand() ? 1 : m_valueList->size();

    if (id == CSSValueInherit) {
        if (num != 1)
            return false;
        addProperty(propId, CSSInheritedValue::create(), important);
        return true;
    }
    else if (id == CSSValueInitial) {
        if (num != 1)
            return false;
        addProperty(propId, CSSInitialValue::createExplicit(), important);
        return true;
    }

    // If we have any variables, then we don't parse the list of values yet.  We add them to the declaration
    // as unresolved, and allow them to be parsed later.  The parse is considered "successful" for now, even though
    // it might ultimately fail once the variable has been resolved.
    if (!inShorthand() && checkForVariables(m_valueList)) {
        addUnresolvedProperty(propId, important);
        return true;
    }

    bool valid_primitive = false;
    RefPtr<CSSValue> parsedValue;

    switch (static_cast<CSSPropertyID>(propId)) {
        /* The comment to the left defines all valid value of this properties as defined
         * in CSS 2, Appendix F. Property index
         */

        /* All the CSS properties are not supported by the renderer at the moment.
         * Note that all the CSS2 Aural properties are only checked, if CSS_AURAL is defined
         * (see parseAuralValues). As we don't support them at all this seems reasonable.
         */

    case CSSPropertySize:                 // <length>{1,2} | auto | portrait | landscape | inherit
    case CSSPropertyQuotes:               // [<string> <string>]+ | none | inherit
        if (id)
            valid_primitive = true;
        break;
    case CSSPropertyUnicodeBidi:         // normal | embed | bidi-override | inherit
        if (id == CSSValueNormal ||
             id == CSSValueEmbed ||
             id == CSSValueBidiOverride)
            valid_primitive = true;
        break;

    case CSSPropertyPosition:             // static | relative | absolute | fixed | inherit
        if (id == CSSValueStatic ||
             id == CSSValueRelative ||
             id == CSSValueAbsolute ||
             id == CSSValueFixed)
            valid_primitive = true;
        break;

    case CSSPropertyPageBreakAfter:     // auto | always | avoid | left | right | inherit
    case CSSPropertyPageBreakBefore:
    case CSSPropertyWebkitColumnBreakAfter:
    case CSSPropertyWebkitColumnBreakBefore:
        if (id == CSSValueAuto ||
             id == CSSValueAlways ||
             id == CSSValueAvoid ||
             id == CSSValueLeft ||
             id == CSSValueRight)
            valid_primitive = true;
        break;

    case CSSPropertyPageBreakInside:    // avoid | auto | inherit
    case CSSPropertyWebkitColumnBreakInside:
        if (id == CSSValueAuto || id == CSSValueAvoid)
            valid_primitive = true;
        break;

    case CSSPropertyEmptyCells:          // show | hide | inherit
        if (id == CSSValueShow ||
             id == CSSValueHide)
            valid_primitive = true;
        break;

    case CSSPropertyContent:              // [ <string> | <uri> | <counter> | attr(X) | open-quote |
        // close-quote | no-open-quote | no-close-quote ]+ | inherit
        return parseContent(propId, important);
        break;

    case CSSPropertyWhiteSpace:          // normal | pre | nowrap | inherit
        if (id == CSSValueNormal ||
            id == CSSValuePre ||
            id == CSSValuePreWrap ||
            id == CSSValuePreLine ||
            id == CSSValueNowrap)
            valid_primitive = true;
        break;

    case CSSPropertyClip:                 // <shape> | auto | inherit
        if (id == CSSValueAuto)
            valid_primitive = true;
        else if (value->unit == CSSParserValue::Function)
            return parseShape(propId, important);
        break;

    /* Start of supported CSS properties with validation. This is needed for parseShorthand to work
     * correctly and allows optimization in WebCore::applyRule(..)
     */
    case CSSPropertyCaptionSide:         // top | bottom | left | right | inherit
        if (id == CSSValueLeft || id == CSSValueRight ||
            id == CSSValueTop || id == CSSValueBottom)
            valid_primitive = true;
        break;

    case CSSPropertyBorderCollapse:      // collapse | separate | inherit
        if (id == CSSValueCollapse || id == CSSValueSeparate)
            valid_primitive = true;
        break;

    case CSSPropertyVisibility:           // visible | hidden | collapse | inherit
        if (id == CSSValueVisible || id == CSSValueHidden || id == CSSValueCollapse)
            valid_primitive = true;
        break;