1/*
2 * Copyright (C) 2010-2017 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 "SharedMemory.h"
29#include "SharedStringHashTable.h"
30#include <WebCore/SharedStringHash.h>
31#include <wtf/HashSet.h>
32#include <wtf/RunLoop.h>
33
34namespace WebKit {
35
36class SharedStringHashStore {
37public:
38 class Client {
39 public:
40 virtual ~Client() { }
41
42 virtual void didInvalidateSharedMemory() = 0;
43 virtual void didUpdateSharedStringHashes(const Vector<WebCore::SharedStringHash>& addedHashes, const Vector<WebCore::SharedStringHash>& removedHashes) { };
44 };
45
46 SharedStringHashStore(Client&);
47
48 bool createSharedMemoryHandle(SharedMemory::Handle&);
49
50 void scheduleAddition(WebCore::SharedStringHash);
51 void scheduleRemoval(WebCore::SharedStringHash);
52
53 bool contains(WebCore::SharedStringHash);
54 void clear();
55
56 bool isEmpty() const { return !m_keyCount; }
57
58 void flushPendingChanges();
59
60private:
61 void resizeTable(unsigned newTableSize);
62 void processPendingOperations();
63
64 struct Operation {
65 enum Type { Add, Remove };
66 Type type;
67 WebCore::SharedStringHash sharedStringHash;
68 };
69
70 Client& m_client;
71 unsigned m_keyCount { 0 };
72 unsigned m_tableSize { 0 };
73 SharedStringHashTable m_table;
74 Vector<Operation> m_pendingOperations;
75 RunLoop::Timer<SharedStringHashStore> m_pendingOperationsTimer;
76};
77
78} // namespace WebKit
79