1 /*
2  * step.h - Copyright 2005 Frerich Raabe <raabe@kde.org>
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 #ifndef STEP_H
26 #define STEP_H
27 
28 #include "predicate.h"
29 #include "util.h"
30 
31 #include <QList>
32 
33 #include <dom/dom_string.h>
34 
35 namespace DOM
36 {
37 class NodeImpl;
38 }
39 
40 namespace khtml
41 {
42 namespace XPath
43 {
44 
45 class Step
46 {
47 public:
48     enum AxisType {
49         AncestorAxis = 1, AncestorOrSelfAxis, AttributeAxis,
50         ChildAxis, DescendantAxis, DescendantOrSelfAxis,
51         FollowingAxis, FollowingSiblingAxis, NamespaceAxis,
52         ParentAxis, PrecedingAxis, PrecedingSiblingAxis,
53         SelfAxis
54     };
55 
56     static QString axisAsString(AxisType axis);
57 
58     Step();
59     Step(AxisType axis,
60          const DOM::DOMString &nodeTest,
61          const QList<Predicate *> &predicates = QList<Predicate *>());
62     ~Step();
63 
64     DomNodeList evaluate(DOM::NodeImpl *context) const;
65 
66     void optimize();
67     QString dump() const;
68 
69 private:
70     DomNodeList nodesInAxis(DOM::NodeImpl *context) const;
71     DomNodeList nodeTestMatches(DOM::NodeImpl *ctx, const DomNodeList &nodes) const;
72     DOM::DOMString namespaceFromNodetest(const DOM::DOMString &nodeTest) const;
73     unsigned int primaryNodeType(AxisType axis) const;
74 
75     // Original axis + nodetest specification
76     AxisType m_axis;
77     DOM::DOMString m_nodeTest;
78 
79     enum CompileState {
80         NotCompiled,
81         CompiledForHTML,
82         CompiledForXML
83     };
84 
85     mutable CompileState m_compileState;
86 
87     void compileNodeTest(bool htmlCompat) const;
88 
89     // Compiled nodetest information. We do this jit'ish due to the
90     // case sensitivity mess.
91     mutable enum {
92         NT_Star,        // *
93         NT_LocalName,   // NCName
94         NT_Namespace,   // NCName:*
95         NT_QName,       // Prefix:LocalName
96         NT_Comment,     // 'comment'
97         NT_Text,        // 'text'
98         NT_PI,          // 'processing-instruction'
99         NT_AnyNode,     // 'node'
100         NT_PI_Lit       // 'processing-instruction' '(' Literal ')'
101     } m_nodeTestType;
102     mutable DOM::LocalName     m_localName;
103     mutable DOM::NamespaceName m_namespace;
104     mutable DOM::DOMString m_piInfo;
105 
106     QList<Predicate *> m_predicates;
107 };
108 
109 } // namespace XPath
110 
111 } // namespace khtml
112 
113 #endif // STEP_H
114 
115