1/*
2 * Copyright (C) 2008, 2009, 2010 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. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef StorageAreaSync_h
27#define StorageAreaSync_h
28
29#include "SQLiteDatabase.h"
30#include "Timer.h"
31#include <wtf/HashMap.h>
32#include <wtf/text/StringHash.h>
33
34namespace WebCore {
35
36class Frame;
37class StorageAreaImpl;
38class StorageSyncManager;
39
40class StorageAreaSync : public ThreadSafeRefCounted<StorageAreaSync> {
41public:
42    static PassRefPtr<StorageAreaSync> create(PassRefPtr<StorageSyncManager>, PassRefPtr<StorageAreaImpl>, const String& databaseIdentifier);
43    ~StorageAreaSync();
44
45    void scheduleFinalSync();
46    void blockUntilImportComplete();
47
48    void scheduleItemForSync(const String& key, const String& value);
49    void scheduleClear();
50    void scheduleCloseDatabase();
51
52    void scheduleSync();
53
54private:
55    StorageAreaSync(PassRefPtr<StorageSyncManager>, PassRefPtr<StorageAreaImpl>, const String& databaseIdentifier);
56
57    void dispatchStorageEvent(const String& key, const String& oldValue, const String& newValue, Frame* sourceFrame);
58
59    Timer<StorageAreaSync> m_syncTimer;
60    HashMap<String, String> m_changedItems;
61    bool m_itemsCleared;
62
63    bool m_finalSyncScheduled;
64
65    RefPtr<StorageAreaImpl> m_storageArea;
66    RefPtr<StorageSyncManager> m_syncManager;
67
68    // The database handle will only ever be opened and used on the background thread.
69    SQLiteDatabase m_database;
70
71    // The following members are subject to thread synchronization issues.
72public:
73    // Called from the background thread
74    void performImport();
75    void performSync();
76    void deleteEmptyDatabase();
77
78private:
79    enum OpenDatabaseParamType {
80      CreateIfNonExistent,
81      SkipIfNonExistent
82    };
83
84    void syncTimerFired(Timer<StorageAreaSync>*);
85    void openDatabase(OpenDatabaseParamType openingStrategy);
86    void sync(bool clearItems, const HashMap<String, String>& items);
87
88    const String m_databaseIdentifier;
89
90    Mutex m_syncLock;
91    HashMap<String, String> m_itemsPendingSync;
92    bool m_clearItemsWhileSyncing;
93    bool m_syncScheduled;
94    bool m_syncInProgress;
95    bool m_databaseOpenFailed;
96
97    bool m_syncCloseDatabase;
98
99    mutable Mutex m_importLock;
100    mutable ThreadCondition m_importCondition;
101    mutable bool m_importComplete;
102    void markImported();
103    void migrateItemTableIfNeeded();
104};
105
106} // namespace WebCore
107
108#endif // StorageAreaSync_h
109