xpathparser.cpp

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            return makeTokenAndAdvance(RELOP, EqTestOp::OP_GT);
        case '*':
            if (isOperatorContext())
                return makeTokenAndAdvance(MULOP, NumericOp::OP_Mul);
            ++m_nextPos;
            return Token(NAMETEST, "*");
        case '$': { // $ QName
            m_nextPos++;
            String name;
            if (!lexQName(name))
                return Token(XPATH_ERROR);
            return Token(VARIABLEREFERENCE, name);
        }
    }

    String name;
    if (!lexNCName(name))
        return Token(XPATH_ERROR);

    skipWS();
    // If we're in an operator context, check for any operator names
    if (isOperatorContext()) {
        if (name == "and") //### hash?
            return Token(AND);
        if (name == "or")
            return Token(OR);
        if (name == "mod")
            return Token(MULOP, NumericOp::OP_Mod);
        if (name == "div")
            return Token(MULOP, NumericOp::OP_Div);
    }

    // See whether we are at a :
    if (peekCurHelper() == ':') {
        m_nextPos++;
        // Any chance it's an axis name?
        if (peekCurHelper() == ':') {
            m_nextPos++;
            
            //It might be an axis name.
            Step::Axis axis;
            if (isAxisName(name, axis))
                return Token(AXISNAME, axis);
            // Ugh, :: is only valid in axis names -> error
            return Token(XPATH_ERROR);
        }

        // Seems like this is a fully qualified qname, or perhaps the * modified one from NameTest
        skipWS();
        if (peekCurHelper() == '*') {
            m_nextPos++;
            return Token(NAMETEST, name + ":*");
        }
        
        // Make a full qname.
        String n2;
        if (!lexNCName(n2))
            return Token(XPATH_ERROR);
        
        name = name + ":" + n2;
    }

    skipWS();
    if (peekCurHelper() == '(') {
        //note: we don't swallow the (here!
        
        //either node type of function name
        if (isNodeTypeName(name)) {
            if (name == "processing-instruction")
                return Token(PI, name);

            return Token(NODETYPE, name);
        }
        //must be a function name.
        return Token(FUNCTIONNAME, name);
    }

    // At this point, it must be NAMETEST.
    return Token(NAMETEST, name);
}

Token Parser::nextToken()
{
    Token toRet = nextTokenInternal();
    m_lastTokenType = toRet.type;
    return toRet;
}

Parser::Parser()
{
    reset(String());
}

void Parser::reset(const String& data)
{
    m_nextPos = 0;
    m_data = data;
    m_lastTokenType = 0;
    
    m_topExpr = 0;
    m_gotNamespaceError = false;
}

int Parser::lex(void* data)
{
    YYSTYPE* yylval = static_cast<YYSTYPE*>(data);
    Token tok = nextToken();

    switch (tok.type) {
        case AXISNAME:
            yylval->axis = tok.axis;
            break;
        case MULOP:
            yylval->numop = tok.numop;
            break;
        case RELOP:
        case EQOP:
            yylval->eqop = tok.eqop;
            break;
        case NODETYPE:
        case PI:
        case FUNCTIONNAME:
        case LITERAL:
        case VARIABLEREFERENCE:
        case NUMBER:
        case NAMETEST:
            yylval->str = new String(tok.str);
            registerString(yylval->str);
            break;
    }

    return tok.type;
}

bool Parser::expandQName(const String& qName, String& localName, String& namespaceURI)
{
    int colon = qName.find(':');
    if (colon >= 0) {
        if (!m_resolver)
            return false;
        namespaceURI = m_resolver->lookupNamespaceURI(qName.left(colon));
        if (namespaceURI.isNull())
            return false;
        localName = qName.substring(colon + 1);
    } else
        localName = qName;
    
    return true;
}

Expression* Parser::parseStatement(const String& statement, PassRefPtr<XPathNSResolver> resolver, ExceptionCode& ec)
{
    reset(statement);

    m_resolver = resolver;
    
    Parser* oldParser = currentParser;
    currentParser = this;
    int parseError = xpathyyparse(this);
    currentParser = oldParser;

    if (parseError) {
        deleteAllValues(m_parseNodes);
        m_parseNodes.clear();

        HashSet<Vector<Predicate*>*>::iterator pend = m_predicateVectors.end();
        for (HashSet<Vector<Predicate*>*>::iterator it = m_predicateVectors.begin(); it != pend; ++it) {
            deleteAllValues(**it);
            delete *it;
        }
        m_predicateVectors.clear();

        HashSet<Vector<Expression*>*>::iterator eend = m_expressionVectors.end();
        for (HashSet<Vector<Expression*>*>::iterator it = m_expressionVectors.begin(); it != eend; ++it) {
            deleteAllValues(**it);
            delete *it;
        }
        m_expressionVectors.clear();

        deleteAllValues(m_strings);
        m_strings.clear();

        deleteAllValues(m_nodeTests);
        m_nodeTests.clear();

        m_topExpr = 0;

        if (m_gotNamespaceError)
            ec = NAMESPACE_ERR;
        else
            ec = XPathException::INVALID_EXPRESSION_ERR;
        return 0;
    }

    ASSERT(m_parseNodes.size() == 1);
    ASSERT(*m_parseNodes.begin() == m_topExpr);
    ASSERT(m_expressionVectors.size() == 0);
    ASSERT(m_predicateVectors.size() == 0);
    ASSERT(m_strings.size() == 0);
    ASSERT(m_nodeTests.size() == 0);

    m_parseNodes.clear();
    Expression* result = m_topExpr;
    m_topExpr = 0;

    return result;
}

void Parser::registerParseNode(ParseNode* node)
{
    if (node == 0)
        return;
    
    ASSERT(!m_parseNodes.contains(node));
    
    m_parseNodes.add(node);
}

void Parser::unregisterParseNode(ParseNode* node)
{
    if (node == 0)
        return;
    
    ASSERT(m_parseNodes.contains(node));

    m_parseNodes.remove(node);
}

void Parser::registerPredicateVector(Vector<Predicate*>* vector)
{
    if (vector == 0)
        return;

    ASSERT(!m_predicateVectors.contains(vector));
    
    m_predicateVectors.add(vector);
}

void Parser::deletePredicateVector(Vector<Predicate*>* vector)
{
    if (vector == 0)
        return;

    ASSERT(m_predicateVectors.contains(vector));
    
    m_predicateVectors.remove(vector);
    delete vector;
}


void Parser::registerExpressionVector(Vector<Expression*>* vector)
{
    if (vector == 0)
        return;

    ASSERT(!m_expressionVectors.contains(vector));
    
    m_expressionVectors.add(vector);    
}

void Parser::deleteExpressionVector(Vector<Expression*>* vector)
{
    if (vector == 0)
        return;

    ASSERT(m_expressionVectors.contains(vector));
    
    m_expressionVectors.remove(vector);
    delete vector;
}

void Parser::registerString(String* s)
{
    if (s == 0)
        return;
    
    ASSERT(!m_strings.contains(s));
    
    m_strings.add(s);        
}

void Parser::deleteString(String* s)
{
    if (s == 0)
        return;
    
    ASSERT(m_strings.contains(s));
    
    m_strings.remove(s);
    delete s;
}

void Parser::registerNodeTest(Step::NodeTest* t)
{
    if (t == 0)
        return;
    
    ASSERT(!m_nodeTests.contains(t));
    
    m_nodeTests.add(t);        
}

void Parser::deleteNodeTest(Step::NodeTest* t)
{
    if (t == 0)
        return;
    
    ASSERT(m_nodeTests.contains(t));
    
    m_nodeTests.remove(t);
    delete t;
}

}
}

#endif // ENABLE(XPATH)