1/*
2 * Copyright (C) 2013 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#include "config.h"
27#include "OriginLock.h"
28
29#if ENABLE(SQL_DATABASE)
30
31#include "FileSystem.h"
32#include <wtf/PassOwnPtr.h>
33
34namespace WebCore {
35
36String OriginLock::lockFileNameForPath(String originPath)
37{
38    return pathByAppendingComponent(originPath, String(".lock"));
39}
40
41OriginLock::OriginLock(String originPath)
42    : m_lockFileName(lockFileNameForPath(originPath).isolatedCopy())
43#if USE(FILE_LOCK)
44    , m_lockHandle(invalidPlatformFileHandle)
45#endif
46{
47}
48
49OriginLock::~OriginLock()
50{
51}
52
53void OriginLock::lock()
54{
55    m_mutex.lock();
56
57#if USE(FILE_LOCK)
58    m_lockHandle = openFile(m_lockFileName, OpenForWrite);
59    if (m_lockHandle == invalidPlatformFileHandle) {
60        // The only way we can get here is if the directory containing the lock
61        // has been deleted or we were given a path to a non-existant directory.
62        // In that case, there's nothing we can do but cleanup and return.
63        m_mutex.unlock();
64        return;
65    }
66
67    lockFile(m_lockHandle, LockExclusive);
68#endif
69}
70
71void OriginLock::unlock()
72{
73#if USE(FILE_LOCK)
74    // If the file descriptor was uninitialized, then that means the directory
75    // containing the lock has been deleted before we opened the lock file, or
76    // we were given a path to a non-existant directory. Which, in turn, means
77    // that there's nothing to unlock.
78    if (m_lockHandle == invalidPlatformFileHandle)
79        return;
80
81    unlockFile(m_lockHandle);
82
83    closeFile(m_lockHandle);
84    m_lockHandle = invalidPlatformFileHandle;
85#endif
86
87    m_mutex.unlock();
88}
89
90void OriginLock::deleteLockFile(String originPath)
91{
92    UNUSED_PARAM(originPath);
93#if USE(FILE_LOCK)
94    String lockFileName = OriginLock::lockFileNameForPath(originPath);
95    deleteFile(lockFileName);
96#endif
97}
98
99} // namespace WebCore
100
101#endif // ENABLE(SQL_DATABASE)
102