1/* 2 * Copyright (C) 2005 Frerich Raabe <raabe@kde.org> 3 * Copyright (C) 2006, 2009 Apple Inc. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27#include "config.h" 28#include "XPathExpression.h" 29 30#include "Document.h" 31#include "ExceptionCode.h" 32#include "XPathException.h" 33#include "XPathExpressionNode.h" 34#include "XPathNSResolver.h" 35#include "XPathParser.h" 36#include "XPathResult.h" 37#include "XPathUtil.h" 38#include <wtf/text/WTFString.h> 39 40namespace WebCore { 41 42using namespace XPath; 43 44PassRefPtr<XPathExpression> XPathExpression::createExpression(const String& expression, XPathNSResolver* resolver, ExceptionCode& ec) 45{ 46 RefPtr<XPathExpression> expr = XPathExpression::create(); 47 Parser parser; 48 49 expr->m_topExpression = parser.parseStatement(expression, resolver, ec); 50 if (!expr->m_topExpression) 51 return 0; 52 53 return expr.release(); 54} 55 56XPathExpression::~XPathExpression() 57{ 58 delete m_topExpression; 59} 60 61PassRefPtr<XPathResult> XPathExpression::evaluate(Node* contextNode, unsigned short type, XPathResult*, ExceptionCode& ec) 62{ 63 if (!isValidContextNode(contextNode)) { 64 ec = NOT_SUPPORTED_ERR; 65 return 0; 66 } 67 68 EvaluationContext& evaluationContext = Expression::evaluationContext(); 69 evaluationContext.node = contextNode; 70 evaluationContext.size = 1; 71 evaluationContext.position = 1; 72 evaluationContext.hadTypeConversionError = false; 73 RefPtr<XPathResult> result = XPathResult::create(contextNode->document(), m_topExpression->evaluate()); 74 evaluationContext.node = 0; // Do not hold a reference to the context node, as this may prevent the whole document from being destroyed in time. 75 76 if (evaluationContext.hadTypeConversionError) { 77 // It is not specified what to do if type conversion fails while evaluating an expression, and INVALID_EXPRESSION_ERR is not exactly right 78 // when the failure happens in an otherwise valid expression because of a variable. But XPathEvaluator does not support variables, so it's close enough. 79 ec = XPathException::INVALID_EXPRESSION_ERR; 80 return 0; 81 } 82 83 if (type != XPathResult::ANY_TYPE) { 84 ec = 0; 85 result->convertTo(type, ec); 86 if (ec) 87 return 0; 88 } 89 90 return result; 91} 92 93} 94