1 /* 2 * Copyright (C) 2005 Frerich Raabe <raabe@kde.org> 3 * Copyright (C) 2006, 2009 Apple Inc. 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 #ifndef XPathExpressionNode_h 28 #define XPathExpressionNode_h 29 30 #if ENABLE(XPATH) 31 32 #include "StringHash.h" 33 #include "Node.h" 34 #include "XPathValue.h" 35 #include <wtf/HashMap.h> 36 #include <wtf/Vector.h> 37 38 namespace WebCore { 39 40 namespace XPath { 41 42 struct EvaluationContext : FastAllocBase { 43 RefPtr<Node> node; 44 unsigned long size; 45 unsigned long position; 46 HashMap<String, String> variableBindings; 47 48 bool hadTypeConversionError; 49 }; 50 51 class ParseNode { 52 public: ~ParseNode()53 virtual ~ParseNode() { } 54 }; 55 56 class Expression : public ParseNode, public Noncopyable { 57 public: 58 static EvaluationContext& evaluationContext(); 59 60 Expression(); 61 virtual ~Expression(); 62 63 virtual Value evaluate() const = 0; 64 addSubExpression(Expression * expr)65 void addSubExpression(Expression* expr) 66 { 67 m_subExpressions.append(expr); 68 m_isContextNodeSensitive |= expr->m_isContextNodeSensitive; 69 m_isContextPositionSensitive |= expr->m_isContextPositionSensitive; 70 m_isContextSizeSensitive |= expr->m_isContextSizeSensitive; 71 } 72 isContextNodeSensitive()73 bool isContextNodeSensitive() const { return m_isContextNodeSensitive; } isContextPositionSensitive()74 bool isContextPositionSensitive() const { return m_isContextPositionSensitive; } isContextSizeSensitive()75 bool isContextSizeSensitive() const { return m_isContextSizeSensitive; } setIsContextNodeSensitive(bool value)76 void setIsContextNodeSensitive(bool value) { m_isContextNodeSensitive = value; } setIsContextPositionSensitive(bool value)77 void setIsContextPositionSensitive(bool value) { m_isContextPositionSensitive = value; } setIsContextSizeSensitive(bool value)78 void setIsContextSizeSensitive(bool value) { m_isContextSizeSensitive = value; } 79 80 virtual Value::Type resultType() const = 0; 81 82 protected: subExprCount()83 unsigned subExprCount() const { return m_subExpressions.size(); } subExpr(unsigned i)84 Expression* subExpr(unsigned i) { return m_subExpressions[i]; } subExpr(unsigned i)85 const Expression* subExpr(unsigned i) const { return m_subExpressions[i]; } 86 87 private: 88 Vector<Expression*> m_subExpressions; 89 90 // Evaluation details that can be used for optimization. 91 bool m_isContextNodeSensitive; 92 bool m_isContextPositionSensitive; 93 bool m_isContextSizeSensitive; 94 }; 95 96 } 97 98 } 99 100 #endif // ENABLE(XPATH) 101 102 #endif // EXPRESSION_H 103 104