1 /*
2 * Copyright (C) 2007, 2008 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 *
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
14 * its contributors may be used to endorse or promote products derived
15 * from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include "config.h"
30 #include "DatabaseThread.h"
31
32 #if ENABLE(DATABASE)
33
34 #include "AutodrainedPool.h"
35 #include "Database.h"
36 #include "DatabaseTask.h"
37 #include "Logging.h"
38
39 namespace WebCore {
40
DatabaseThread()41 DatabaseThread::DatabaseThread()
42 : m_threadID(0)
43 {
44 m_selfRef = this;
45 }
46
~DatabaseThread()47 DatabaseThread::~DatabaseThread()
48 {
49 // FIXME: Any cleanup required here? Since the thread deletes itself after running its detached course, I don't think so. Lets be sure.
50 }
51
start()52 bool DatabaseThread::start()
53 {
54 MutexLocker lock(m_threadCreationMutex);
55
56 if (m_threadID)
57 return true;
58
59 m_threadID = createThread(DatabaseThread::databaseThreadStart, this, "WebCore: Database");
60
61 return m_threadID;
62 }
63
requestTermination()64 void DatabaseThread::requestTermination()
65 {
66 LOG(StorageAPI, "DatabaseThread %p was asked to terminate\n", this);
67 m_queue.kill();
68 }
69
terminationRequested() const70 bool DatabaseThread::terminationRequested() const
71 {
72 return m_queue.killed();
73 }
74
databaseThreadStart(void * vDatabaseThread)75 void* DatabaseThread::databaseThreadStart(void* vDatabaseThread)
76 {
77 DatabaseThread* dbThread = static_cast<DatabaseThread*>(vDatabaseThread);
78 return dbThread->databaseThread();
79 }
80
databaseThread()81 void* DatabaseThread::databaseThread()
82 {
83 {
84 // Wait for DatabaseThread::start() to complete.
85 MutexLocker lock(m_threadCreationMutex);
86 LOG(StorageAPI, "Started DatabaseThread %p", this);
87 }
88
89 AutodrainedPool pool;
90 while (true) {
91 RefPtr<DatabaseTask> task;
92 if (!m_queue.waitForMessage(task))
93 break;
94
95 task->performTask();
96
97 pool.cycle();
98 }
99
100 LOG(StorageAPI, "About to detach thread %i and clear the ref to DatabaseThread %p, which currently has %i ref(s)", m_threadID, this, refCount());
101
102 // Close the databases that we ran transactions on. This ensures that if any transactions are still open, they are rolled back and we don't leave the database in an
103 // inconsistent or locked state.
104 if (m_openDatabaseSet.size() > 0) {
105 // As the call to close will modify the original set, we must take a copy to iterate over.
106 DatabaseSet openSetCopy;
107 openSetCopy.swap(m_openDatabaseSet);
108 DatabaseSet::iterator end = openSetCopy.end();
109 for (DatabaseSet::iterator it = openSetCopy.begin(); it != end; ++it)
110 (*it)->close();
111 }
112
113 // Detach the thread so its resources are no longer of any concern to anyone else
114 detachThread(m_threadID);
115
116 // Clear the self refptr, possibly resulting in deletion
117 m_selfRef = 0;
118
119 return 0;
120 }
121
recordDatabaseOpen(Database * database)122 void DatabaseThread::recordDatabaseOpen(Database* database)
123 {
124 ASSERT(currentThread() == m_threadID);
125 ASSERT(database);
126 ASSERT(!m_openDatabaseSet.contains(database));
127 m_openDatabaseSet.add(database);
128 }
129
recordDatabaseClosed(Database * database)130 void DatabaseThread::recordDatabaseClosed(Database* database)
131 {
132 ASSERT(currentThread() == m_threadID);
133 ASSERT(database);
134 ASSERT(m_queue.killed() || m_openDatabaseSet.contains(database));
135 m_openDatabaseSet.remove(database);
136 }
137
scheduleTask(PassRefPtr<DatabaseTask> task)138 void DatabaseThread::scheduleTask(PassRefPtr<DatabaseTask> task)
139 {
140 m_queue.append(task);
141 }
142
scheduleImmediateTask(PassRefPtr<DatabaseTask> task)143 void DatabaseThread::scheduleImmediateTask(PassRefPtr<DatabaseTask> task)
144 {
145 m_queue.prepend(task);
146 }
147
unscheduleDatabaseTasks(Database * database)148 void DatabaseThread::unscheduleDatabaseTasks(Database* database)
149 {
150 // Note that the thread loop is running, so some tasks for the database
151 // may still be executed. This is unavoidable.
152
153 Deque<RefPtr<DatabaseTask> > filteredReverseQueue;
154 RefPtr<DatabaseTask> task;
155 while (m_queue.tryGetMessage(task)) {
156 if (task->database() != database)
157 filteredReverseQueue.append(task);
158 }
159
160 while (!filteredReverseQueue.isEmpty()) {
161 m_queue.append(filteredReverseQueue.first());
162 filteredReverseQueue.removeFirst();
163 }
164 }
165
166 } // namespace WebCore
167 #endif
168