1 /*
2 * Copyright 2010, The Android Open Source Project
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 * * Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * * 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 THE COPYRIGHT HOLDERS ``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 THE COPYRIGHT OWNER 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 "GeolocationPositionCache.h"
28
29 #if ENABLE(GEOLOCATION)
30
31 #include "CrossThreadTask.h"
32 #include "Geoposition.h"
33 #include "SQLValue.h"
34 #include "SQLiteDatabase.h"
35 #include "SQLiteFileSystem.h"
36 #include "SQLiteStatement.h"
37 #include "SQLiteTransaction.h"
38 #include <wtf/PassOwnPtr.h>
39 #include <wtf/Threading.h>
40
41 using namespace WTF;
42
43 namespace WebCore {
44
45 static int numUsers = 0;
46
instance()47 GeolocationPositionCache* GeolocationPositionCache::instance()
48 {
49 DEFINE_STATIC_LOCAL(GeolocationPositionCache*, instance, (0));
50 if (!instance)
51 instance = new GeolocationPositionCache();
52 return instance;
53 }
54
GeolocationPositionCache()55 GeolocationPositionCache::GeolocationPositionCache()
56 : m_threadId(0)
57 {
58 }
59
addUser()60 void GeolocationPositionCache::addUser()
61 {
62 ASSERT(numUsers >= 0);
63 MutexLocker databaseLock(m_databaseFileMutex);
64 if (!numUsers && !m_threadId && !m_databaseFile.isNull()) {
65 startBackgroundThread();
66 MutexLocker lock(m_cachedPositionMutex);
67 if (!m_cachedPosition)
68 triggerReadFromDatabase();
69 }
70 ++numUsers;
71 }
72
removeUser()73 void GeolocationPositionCache::removeUser()
74 {
75 MutexLocker lock(m_cachedPositionMutex);
76 --numUsers;
77 ASSERT(numUsers >= 0);
78 if (!numUsers && m_cachedPosition && m_threadId)
79 triggerWriteToDatabase();
80 }
81
setDatabasePath(const String & path)82 void GeolocationPositionCache::setDatabasePath(const String& path)
83 {
84 static const char* databaseName = "CachedGeoposition.db";
85 String newFile = SQLiteFileSystem::appendDatabaseFileNameToPath(path, databaseName);
86 MutexLocker lock(m_databaseFileMutex);
87 if (m_databaseFile != newFile) {
88 m_databaseFile = newFile;
89 if (numUsers && !m_threadId) {
90 startBackgroundThread();
91 if (!m_cachedPosition)
92 triggerReadFromDatabase();
93 }
94 }
95 }
96
setCachedPosition(Geoposition * cachedPosition)97 void GeolocationPositionCache::setCachedPosition(Geoposition* cachedPosition)
98 {
99 MutexLocker lock(m_cachedPositionMutex);
100 m_cachedPosition = cachedPosition;
101 }
102
cachedPosition()103 Geoposition* GeolocationPositionCache::cachedPosition()
104 {
105 MutexLocker lock(m_cachedPositionMutex);
106 return m_cachedPosition.get();
107 }
108
startBackgroundThread()109 void GeolocationPositionCache::startBackgroundThread()
110 {
111 // FIXME: Consider sharing this thread with other background tasks.
112 m_threadId = createThread(threadEntryPoint, this, "WebCore: Geolocation cache");
113 }
114
threadEntryPoint(void * object)115 void* GeolocationPositionCache::threadEntryPoint(void* object)
116 {
117 static_cast<GeolocationPositionCache*>(object)->threadEntryPointImpl();
118 return 0;
119 }
120
threadEntryPointImpl()121 void GeolocationPositionCache::threadEntryPointImpl()
122 {
123 while (OwnPtr<ScriptExecutionContext::Task> task = m_queue.waitForMessage()) {
124 // We don't need a ScriptExecutionContext in the callback, so pass 0 here.
125 task->performTask(0);
126 }
127 }
128
triggerReadFromDatabase()129 void GeolocationPositionCache::triggerReadFromDatabase()
130 {
131 m_queue.append(createCallbackTask(&GeolocationPositionCache::readFromDatabase, this));
132 }
133
readFromDatabase(ScriptExecutionContext *,GeolocationPositionCache * cache)134 void GeolocationPositionCache::readFromDatabase(ScriptExecutionContext*, GeolocationPositionCache* cache)
135 {
136 cache->readFromDatabaseImpl();
137 }
138
readFromDatabaseImpl()139 void GeolocationPositionCache::readFromDatabaseImpl()
140 {
141 SQLiteDatabase database;
142 {
143 MutexLocker lock(m_databaseFileMutex);
144 if (!database.open(m_databaseFile))
145 return;
146 }
147
148 // Create the table here, such that even if we've just created the
149 // DB, the commands below should succeed.
150 if (!database.executeCommand("CREATE TABLE IF NOT EXISTS CachedPosition ("
151 "latitude REAL NOT NULL, "
152 "longitude REAL NOT NULL, "
153 "altitude REAL, "
154 "accuracy REAL NOT NULL, "
155 "altitudeAccuracy REAL, "
156 "heading REAL, "
157 "speed REAL, "
158 "timestamp INTEGER NOT NULL)"))
159 return;
160
161 SQLiteStatement statement(database, "SELECT * FROM CachedPosition");
162 if (statement.prepare() != SQLResultOk)
163 return;
164
165 if (statement.step() != SQLResultRow)
166 return;
167
168 bool providesAltitude = statement.getColumnValue(2).type() != SQLValue::NullValue;
169 bool providesAltitudeAccuracy = statement.getColumnValue(4).type() != SQLValue::NullValue;
170 bool providesHeading = statement.getColumnValue(5).type() != SQLValue::NullValue;
171 bool providesSpeed = statement.getColumnValue(6).type() != SQLValue::NullValue;
172 RefPtr<Coordinates> coordinates = Coordinates::create(statement.getColumnDouble(0), // latitude
173 statement.getColumnDouble(1), // longitude
174 providesAltitude, statement.getColumnDouble(2), // altitude
175 statement.getColumnDouble(3), // accuracy
176 providesAltitudeAccuracy, statement.getColumnDouble(4), // altitudeAccuracy
177 providesHeading, statement.getColumnDouble(5), // heading
178 providesSpeed, statement.getColumnDouble(6)); // speed
179 DOMTimeStamp timestamp = statement.getColumnInt64(7); // timestamp
180
181 // A position may have been set since we called triggerReadFromDatabase().
182 MutexLocker lock(m_cachedPositionMutex);
183 if (m_cachedPosition)
184 return;
185 m_cachedPosition = Geoposition::create(coordinates.release(), timestamp);
186 }
187
triggerWriteToDatabase()188 void GeolocationPositionCache::triggerWriteToDatabase()
189 {
190 m_queue.append(createCallbackTask(writeToDatabase, this));
191 }
192
writeToDatabase(ScriptExecutionContext *,GeolocationPositionCache * cache)193 void GeolocationPositionCache::writeToDatabase(ScriptExecutionContext*, GeolocationPositionCache* cache)
194 {
195 cache->writeToDatabaseImpl();
196 }
197
writeToDatabaseImpl()198 void GeolocationPositionCache::writeToDatabaseImpl()
199 {
200 SQLiteDatabase database;
201 {
202 MutexLocker lock(m_databaseFileMutex);
203 if (!database.open(m_databaseFile))
204 return;
205 }
206
207 RefPtr<Geoposition> cachedPosition;
208 {
209 MutexLocker lock(m_cachedPositionMutex);
210 if (m_cachedPosition)
211 cachedPosition = m_cachedPosition->threadSafeCopy();
212 }
213
214 SQLiteTransaction transaction(database);
215
216 if (!database.executeCommand("DELETE FROM CachedPosition"))
217 return;
218
219 SQLiteStatement statement(database, "INSERT INTO CachedPosition ("
220 "latitude, "
221 "longitude, "
222 "altitude, "
223 "accuracy, "
224 "altitudeAccuracy, "
225 "heading, "
226 "speed, "
227 "timestamp) "
228 "VALUES (?, ?, ?, ?, ?, ?, ?, ?)");
229 if (statement.prepare() != SQLResultOk)
230 return;
231
232 statement.bindDouble(1, cachedPosition->coords()->latitude());
233 statement.bindDouble(2, cachedPosition->coords()->longitude());
234 if (cachedPosition->coords()->canProvideAltitude())
235 statement.bindDouble(3, cachedPosition->coords()->altitude());
236 else
237 statement.bindNull(3);
238 statement.bindDouble(4, cachedPosition->coords()->accuracy());
239 if (cachedPosition->coords()->canProvideAltitudeAccuracy())
240 statement.bindDouble(5, cachedPosition->coords()->altitudeAccuracy());
241 else
242 statement.bindNull(5);
243 if (cachedPosition->coords()->canProvideHeading())
244 statement.bindDouble(6, cachedPosition->coords()->heading());
245 else
246 statement.bindNull(6);
247 if (cachedPosition->coords()->canProvideSpeed())
248 statement.bindDouble(7, cachedPosition->coords()->speed());
249 else
250 statement.bindNull(7);
251 statement.bindInt64(8, cachedPosition->timestamp());
252
253 if (!statement.executeCommand())
254 return;
255
256 transaction.commit();
257 }
258
259 } // namespace WebCore
260
261 #endif // ENABLE(GEOLOCATION)
262