1/*
2 * Copyright (C) 2013-2019 Apple 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
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
23 * THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#pragma once
27
28#include <wtf/DoublyLinkedList.h>
29
30namespace JSC {
31
32class HandleSet;
33class HandleNode;
34
35class HandleBlock : public DoublyLinkedListNode<HandleBlock> {
36 friend class WTF::DoublyLinkedListNode<HandleBlock>;
37public:
38 static HandleBlock* create(HandleSet*);
39 static void destroy(HandleBlock*);
40 static HandleBlock* blockFor(HandleNode*);
41
42 static constexpr size_t blockSize = 4 * KB;
43
44 HandleSet* handleSet();
45
46 HandleNode* nodes();
47 HandleNode* nodeAtIndex(unsigned);
48 unsigned nodeCapacity();
49
50private:
51 HandleBlock(HandleSet*);
52
53 char* payload();
54 char* payloadEnd();
55
56 static constexpr size_t s_blockMask = ~(blockSize - 1);
57
58 HandleBlock* m_prev;
59 HandleBlock* m_next;
60 HandleSet* m_handleSet;
61};
62
63inline HandleBlock* HandleBlock::blockFor(HandleNode* node)
64{
65 return reinterpret_cast<HandleBlock*>(reinterpret_cast<size_t>(node) & s_blockMask);
66}
67
68inline HandleSet* HandleBlock::handleSet()
69{
70 return m_handleSet;
71}
72
73} // namespace JSC
74