1 /* 2 * Copyright (C) 2005 Frerich Raabe <raabe (at) 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 #if ENABLE(XPATH) 31 32 #include "Document.h" 33 #include "PlatformString.h" 34 #include "XPathException.h" 35 #include "XPathExpressionNode.h" 36 #include "XPathNSResolver.h" 37 #include "XPathParser.h" 38 #include "XPathResult.h" 39 #include "XPathUtil.h" 40 41 namespace WebCore { 42 43 using namespace XPath; 44 45 PassRefPtr<XPathExpression> XPathExpression::createExpression(const String& expression, XPathNSResolver* resolver, ExceptionCode& ec) 46 { 47 RefPtr<XPathExpression> expr = XPathExpression::create(); 48 Parser parser; 49 50 expr->m_topExpression = parser.parseStatement(expression, resolver, ec); 51 if (!expr->m_topExpression) 52 return 0; 53 54 return expr.release(); 55 } 56 57 XPathExpression::~XPathExpression() 58 { 59 delete m_topExpression; 60 } 61 62 PassRefPtr<XPathResult> XPathExpression::evaluate(Node* contextNode, unsigned short type, XPathResult*, ExceptionCode& ec) 63 { 64 if (!isValidContextNode(contextNode)) { 65 ec = NOT_SUPPORTED_ERR; 66 return 0; 67 } 68 69 EvaluationContext& evaluationContext = Expression::evaluationContext(); 70 evaluationContext.node = contextNode; 71 evaluationContext.size = 1; 72 evaluationContext.position = 1; 73 evaluationContext.hadTypeConversionError = false; 74 RefPtr<XPathResult> result = XPathResult::create(contextNode->document(), m_topExpression->evaluate()); 75 evaluationContext.node = 0; // Do not hold a reference to the context node, as this may prevent the whole document from being destroyed in time. 76 77 if (evaluationContext.hadTypeConversionError) { 78 // It is not specified what to do if type conversion fails while evaluating an expression, and INVALID_EXPRESSION_ERR is not exactly right 79 // when the failure happens in an otherwise valid expression because of a variable. But XPathEvaluator does not support variables, so it's close enough. 80 ec = XPathException::INVALID_EXPRESSION_ERR; 81 return 0; 82 } 83 84 if (type != XPathResult::ANY_TYPE) { 85 ec = 0; 86 result->convertTo(type, ec); 87 if (ec) 88 return 0; 89 } 90 91 return result; 92 } 93 94 } 95 96 #endif // ENABLE(XPATH) 97