1/*
2 * Copyright (C) 2014 Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met:
7 *
8 *     * Redistributions of source code must retain the above copyright
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
13 * distribution.
14 *     * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#ifndef HeapLinkedStack_h
32#define HeapLinkedStack_h
33
34#include "platform/heap/Heap.h"
35#include "platform/heap/Visitor.h"
36
37namespace blink {
38
39template <typename T>
40class HeapLinkedStack : public GarbageCollected<HeapLinkedStack<T> > {
41public:
42    HeapLinkedStack() : m_size(0) { }
43
44    bool isEmpty();
45
46    void push(const T&);
47    const T& peek();
48    void pop();
49
50    size_t size();
51
52    void trace(Visitor* visitor)
53    {
54        for (Node* current = m_head; current; current = current->m_next)
55            visitor->trace(current);
56    }
57
58private:
59    class Node : public GarbageCollected<Node> {
60    public:
61        Node(const T&, Node* next);
62
63        void trace(Visitor* visitor) { visitor->trace(m_data); }
64
65        T m_data;
66        Member<Node> m_next;
67    };
68
69    Member<Node> m_head;
70    size_t m_size;
71};
72
73template <typename T>
74HeapLinkedStack<T>::Node::Node(const T& data, Node* next)
75    : m_data(data)
76    , m_next(next)
77{
78}
79
80template <typename T>
81inline bool HeapLinkedStack<T>::isEmpty()
82{
83    return !m_head;
84}
85
86template <typename T>
87inline void HeapLinkedStack<T>::push(const T& data)
88{
89    m_head = new Node(data, m_head);
90    ++m_size;
91}
92
93template <typename T>
94inline const T& HeapLinkedStack<T>::peek()
95{
96    return m_head->m_data;
97}
98
99template <typename T>
100inline void HeapLinkedStack<T>::pop()
101{
102    ASSERT(m_head && m_size);
103    m_head = m_head->m_next;
104    --m_size;
105}
106
107template <typename T>
108inline size_t HeapLinkedStack<T>::size()
109{
110    return m_size;
111}
112
113}
114
115#endif // HeapLinkedStack_h
116