1 /*
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3  *
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5  * modification, are permitted provided that the following conditions are
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9  * notice, this list of conditions and the following disclaimer.
10  *     * Redistributions in binary form must reproduce the above
11  * copyright notice, this list of conditions and the following disclaimer
12  * in the documentation and/or other materials provided with the
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29  */
30 
31 #ifndef DocumentOrderedMap_h
32 #define DocumentOrderedMap_h
33 
34 #include <wtf/HashCountedSet.h>
35 #include <wtf/HashMap.h>
36 #include <wtf/text/AtomicStringImpl.h>
37 
38 namespace WebCore {
39 
40 class Element;
41 class TreeScope;
42 
43 class DocumentOrderedMap {
44 public:
45     void add(AtomicStringImpl*, Element*);
46     void remove(AtomicStringImpl*, Element*);
47     void clear();
48 
49     bool contains(AtomicStringImpl*) const;
50     bool containsMultiple(AtomicStringImpl*) const;
51     // concrete instantiations of the get<>() method template
52     Element* getElementById(AtomicStringImpl*, const TreeScope*) const;
53     Element* getElementByMapName(AtomicStringImpl*, const TreeScope*) const;
54     Element* getElementByLowercasedMapName(AtomicStringImpl*, const TreeScope*) const;
55 
56     void checkConsistency() const;
57 
58 private:
59     template<bool keyMatches(AtomicStringImpl*, Element*)> Element* get(AtomicStringImpl*, const TreeScope*) const;
60 
61     typedef HashMap<AtomicStringImpl*, Element*> Map;
62 
63     // We maintain the invariant that m_duplicateCounts is the count of all elements with a given key
64     // excluding the one referenced in m_map, if any. This means it one less than the total count
65     // when the first node with a given key is cached, otherwise the same as the total count.
66     mutable Map m_map;
67     mutable HashCountedSet<AtomicStringImpl*> m_duplicateCounts;
68 };
69 
contains(AtomicStringImpl * id)70 inline bool DocumentOrderedMap::contains(AtomicStringImpl* id) const
71 {
72     return m_map.contains(id) || m_duplicateCounts.contains(id);
73 }
74 
containsMultiple(AtomicStringImpl * id)75 inline bool DocumentOrderedMap::containsMultiple(AtomicStringImpl* id) const
76 {
77     return m_duplicateCounts.contains(id);
78 }
79 
80 } // namespace WebCore
81 
82 #endif // DocumentOrderedMap_h
83 
84