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#ifndef GeolocationPositionCache_h 27#define GeolocationPositionCache_h 28 29#include "PlatformString.h" 30#include "ScriptExecutionContext.h" 31 32#include <wtf/Forward.h> 33#include <wtf/MessageQueue.h> 34#include <wtf/PassRefPtr.h> 35#include <wtf/RefPtr.h> 36 37namespace WebCore { 38 39class Geoposition; 40 41// Maintains a cached position for Geolocation. Takes care of writing and 42// reading the position to a database on a background thread. The Geolocation 43// spec does not require a cached position to be maintained, so we take a 44// best-effort approach where we do not wait for database reads or writes. 45class GeolocationPositionCache { 46public: 47 static GeolocationPositionCache* instance(); 48 49 void addUser(); 50 void removeUser(); 51 52 void setDatabasePath(const String&); 53 void setCachedPosition(Geoposition*); 54 Geoposition* cachedPosition(); 55 56private: 57 GeolocationPositionCache(); 58 59 void startBackgroundThread(); 60 static void* threadEntryPoint(void* object); 61 void threadEntryPointImpl(); 62 63 void triggerReadFromDatabase(); 64 static void readFromDatabase(ScriptExecutionContext*, GeolocationPositionCache*); 65 void readFromDatabaseImpl(); 66 void triggerWriteToDatabase(); 67 static void writeToDatabase(ScriptExecutionContext*, GeolocationPositionCache*); 68 void writeToDatabaseImpl(); 69 70 RefPtr<Geoposition> m_cachedPosition; 71 Mutex m_cachedPositionMutex; 72 ThreadIdentifier m_threadId; 73 MessageQueue<ScriptExecutionContext::Task> m_queue; 74 String m_databaseFile; 75 Mutex m_databaseFileMutex; 76}; 77 78} // namespace WebCore 79 80#endif // GeolocationPositionCache_h 81