1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef ANDROID_SENSOR_SERVICE_H 18 #define ANDROID_SENSOR_SERVICE_H 19 20 #include <stdint.h> 21 #include <sys/types.h> 22 23 #include <utils/Vector.h> 24 #include <utils/SortedVector.h> 25 #include <utils/KeyedVector.h> 26 #include <utils/threads.h> 27 #include <utils/AndroidThreads.h> 28 #include <utils/RefBase.h> 29 #include <utils/Looper.h> 30 31 #include <binder/BinderService.h> 32 33 #include <gui/Sensor.h> 34 #include <gui/BitTube.h> 35 #include <gui/ISensorServer.h> 36 #include <gui/ISensorEventConnection.h> 37 38 #include "SensorInterface.h" 39 40 // --------------------------------------------------------------------------- 41 42 #define DEBUG_CONNECTIONS false 43 // Max size is 100 KB which is enough to accept a batch of about 1000 events. 44 #define MAX_SOCKET_BUFFER_SIZE_BATCHED 100 * 1024 45 // For older HALs which don't support batching, use a smaller socket buffer size. 46 #define SOCKET_BUFFER_SIZE_NON_BATCHED 4 * 1024 47 48 struct sensors_poll_device_t; 49 struct sensors_module_t; 50 51 namespace android { 52 // --------------------------------------------------------------------------- 53 54 class SensorService : 55 public BinderService<SensorService>, 56 public BnSensorServer, 57 protected Thread 58 { 59 friend class BinderService<SensorService>; 60 61 static const char* WAKE_LOCK_NAME; 62 63 static char const* getServiceName() ANDROID_API { return "sensorservice"; } 64 SensorService() ANDROID_API; 65 virtual ~SensorService(); 66 67 virtual void onFirstRef(); 68 69 // Thread interface 70 virtual bool threadLoop(); 71 72 // ISensorServer interface 73 virtual Vector<Sensor> getSensorList(); 74 virtual sp<ISensorEventConnection> createSensorEventConnection(); 75 virtual status_t dump(int fd, const Vector<String16>& args); 76 77 class SensorEventConnection : public BnSensorEventConnection, public LooperCallback { 78 friend class SensorService; 79 virtual ~SensorEventConnection(); 80 virtual void onFirstRef(); 81 virtual sp<BitTube> getSensorChannel() const; 82 virtual status_t enableDisable(int handle, bool enabled, nsecs_t samplingPeriodNs, 83 nsecs_t maxBatchReportLatencyNs, int reservedFlags); 84 virtual status_t setEventRate(int handle, nsecs_t samplingPeriodNs); 85 virtual status_t flush(); 86 // Count the number of flush complete events which are about to be dropped in the buffer. 87 // Increment mPendingFlushEventsToSend in mSensorInfo. These flush complete events will be 88 // sent separately before the next batch of events. 89 void countFlushCompleteEventsLocked(sensors_event_t const* scratch, int numEventsDropped); 90 91 // Check if there are any wake up events in the buffer. If yes, return the index of the 92 // first wake_up sensor event in the buffer else return -1. This wake_up sensor event will 93 // have the flag WAKE_UP_SENSOR_EVENT_NEEDS_ACK set. Exactly one event per packet will have 94 // the wake_up flag set. SOCK_SEQPACKET ensures that either the entire packet is read or 95 // dropped. 96 int findWakeUpSensorEventLocked(sensors_event_t const* scratch, int count); 97 98 // Send pending flush_complete events. There may have been flush_complete_events that are 99 // dropped which need to be sent separately before other events. On older HALs (1_0) this 100 // method emulates the behavior of flush(). 101 void sendPendingFlushEventsLocked(); 102 103 // Writes events from mEventCache to the socket. 104 void writeToSocketFromCache(); 105 106 // Compute the approximate cache size from the FIFO sizes of various sensors registered for 107 // this connection. Wake up and non-wake up sensors have separate FIFOs but FIFO may be 108 // shared amongst wake-up sensors and non-wake up sensors. 109 int computeMaxCacheSizeLocked() const; 110 111 // When more sensors register, the maximum cache size desired may change. Compute max cache 112 // size, reallocate memory and copy over events from the older cache. 113 void reAllocateCacheLocked(sensors_event_t const* scratch, int count); 114 115 // LooperCallback method. If there is data to read on this fd, it is an ack from the 116 // app that it has read events from a wake up sensor, decrement mWakeLockRefCount. 117 // If this fd is available for writing send the data from the cache. 118 virtual int handleEvent(int fd, int events, void* data); 119 120 // Increment mPendingFlushEventsToSend for the given sensor handle. 121 void incrementPendingFlushCount(int32_t handle); 122 123 // Add or remove the file descriptor associated with the BitTube to the looper. If mDead is 124 // set to true or there are no more sensors for this connection, the file descriptor is 125 // removed if it has been previously added to the Looper. Depending on the state of the 126 // connection FD may be added to the Looper. The flags to set are determined by the internal 127 // state of the connection. FDs are added to the looper when wake-up sensors are registered 128 // (to poll for acknowledgements) and when write fails on the socket when there are too many 129 // events (to poll when the FD is available for writing). FDs are removed when there is an 130 // error and the other end hangs up or when this client unregisters for this connection. 131 void updateLooperRegistration(const sp<Looper>& looper); 132 void updateLooperRegistrationLocked(const sp<Looper>& looper); 133 134 sp<SensorService> const mService; 135 sp<BitTube> mChannel; 136 uid_t mUid; 137 mutable Mutex mConnectionLock; 138 // Number of events from wake up sensors which are still pending and haven't been delivered 139 // to the corresponding application. It is incremented by one unit for each write to the 140 // socket. 141 uint32_t mWakeLockRefCount; 142 143 // If this flag is set to true, it means that the file descriptor associated with the 144 // BitTube has been added to the Looper in SensorService. This flag is typically set when 145 // this connection has wake-up sensors associated with it or when write has failed on this 146 // connection and we're storing some events in the cache. 147 bool mHasLooperCallbacks; 148 // If there are any errors associated with the Looper this flag is set to true and 149 // mWakeLockRefCount is reset to zero. needsWakeLock method will always return false, if 150 // this flag is set. 151 bool mDead; 152 struct FlushInfo { 153 // The number of flush complete events dropped for this sensor is stored here. 154 // They are sent separately before the next batch of events. 155 int mPendingFlushEventsToSend; 156 // Every activate is preceded by a flush. Only after the first flush complete is 157 // received, the events for the sensor are sent on that *connection*. 158 bool mFirstFlushPending; 159 FlushInfo() : mPendingFlushEventsToSend(0), mFirstFlushPending(false) {} 160 }; 161 // protected by SensorService::mLock. Key for this vector is the sensor handle. 162 KeyedVector<int, FlushInfo> mSensorInfo; 163 sensors_event_t *mEventCache; 164 int mCacheSize, mMaxCacheSize; 165 166 #if DEBUG_CONNECTIONS 167 int mEventsReceived, mEventsSent, mEventsSentFromCache; 168 int mTotalAcksNeeded, mTotalAcksReceived; 169 #endif 170 171 public: 172 SensorEventConnection(const sp<SensorService>& service, uid_t uid); 173 174 status_t sendEvents(sensors_event_t const* buffer, size_t count, 175 sensors_event_t* scratch, 176 SensorEventConnection const * const * mapFlushEventsToConnections = NULL); 177 bool hasSensor(int32_t handle) const; 178 bool hasAnySensor() const; 179 bool hasOneShotSensors() const; 180 bool addSensor(int32_t handle); 181 bool removeSensor(int32_t handle); 182 void setFirstFlushPending(int32_t handle, bool value); 183 void dump(String8& result); 184 bool needsWakeLock(); 185 void resetWakeLockRefCount(); 186 187 uid_t getUid() const { return mUid; } 188 }; 189 190 class SensorRecord { 191 SortedVector< wp<SensorEventConnection> > mConnections; 192 // A queue of all flush() calls made on this sensor. Flush complete events will be 193 // sent in this order. 194 Vector< wp<SensorEventConnection> > mPendingFlushConnections; 195 public: 196 SensorRecord(const sp<SensorEventConnection>& connection); 197 bool addConnection(const sp<SensorEventConnection>& connection); 198 bool removeConnection(const wp<SensorEventConnection>& connection); 199 size_t getNumConnections() const { return mConnections.size(); } 200 201 void addPendingFlushConnection(const sp<SensorEventConnection>& connection); 202 void removeFirstPendingFlushConnection(); 203 SensorEventConnection * getFirstPendingFlushConnection(); 204 }; 205 206 class SensorEventAckReceiver : public Thread { 207 sp<SensorService> const mService; 208 public: 209 virtual bool threadLoop(); 210 SensorEventAckReceiver(const sp<SensorService>& service): mService(service) {} 211 }; 212 213 String8 getSensorName(int handle) const; 214 bool isVirtualSensor(int handle) const; 215 Sensor getSensorFromHandle(int handle) const; 216 bool isWakeUpSensor(int type) const; 217 void recordLastValueLocked(sensors_event_t const* buffer, size_t count); 218 static void sortEventBuffer(sensors_event_t* buffer, size_t count); 219 Sensor registerSensor(SensorInterface* sensor); 220 Sensor registerVirtualSensor(SensorInterface* sensor); 221 status_t cleanupWithoutDisable( 222 const sp<SensorEventConnection>& connection, int handle); 223 status_t cleanupWithoutDisableLocked( 224 const sp<SensorEventConnection>& connection, int handle); 225 void cleanupAutoDisabledSensorLocked(const sp<SensorEventConnection>& connection, 226 sensors_event_t const* buffer, const int count); 227 static bool canAccessSensor(const Sensor& sensor); 228 static bool verifyCanAccessSensor(const Sensor& sensor, const char* operation); 229 // SensorService acquires a partial wakelock for delivering events from wake up sensors. This 230 // method checks whether all the events from these wake up sensors have been delivered to the 231 // corresponding applications, if yes the wakelock is released. 232 void checkWakeLockState(); 233 void checkWakeLockStateLocked(); 234 bool isWakeLockAcquired(); 235 bool isWakeUpSensorEvent(const sensors_event_t& event) const; 236 237 SensorRecord * getSensorRecord(int handle); 238 239 sp<Looper> getLooper() const; 240 241 // Reset mWakeLockRefCounts for all SensorEventConnections to zero. This may happen if 242 // SensorService did not receive any acknowledgements from apps which have registered for 243 // wake_up sensors. 244 void resetAllWakeLockRefCounts(); 245 246 // Acquire or release wake_lock. If wake_lock is acquired, set the timeout in the looper to 247 // 5 seconds and wake the looper. 248 void setWakeLockAcquiredLocked(bool acquire); 249 250 // Send events from the event cache for this particular connection. 251 void sendEventsFromCache(const sp<SensorEventConnection>& connection); 252 253 // Promote all weak referecences in mActiveConnections vector to strong references and add them 254 // to the output vector. 255 void populateActiveConnections(SortedVector< sp<SensorEventConnection> >* activeConnections); 256 257 // constants 258 Vector<Sensor> mSensorList; 259 Vector<Sensor> mUserSensorListDebug; 260 Vector<Sensor> mUserSensorList; 261 DefaultKeyedVector<int, SensorInterface*> mSensorMap; 262 Vector<SensorInterface *> mVirtualSensorList; 263 status_t mInitCheck; 264 // Socket buffersize used to initialize BitTube. This size depends on whether batching is 265 // supported or not. 266 uint32_t mSocketBufferSize; 267 sp<Looper> mLooper; 268 sp<SensorEventAckReceiver> mAckReceiver; 269 270 // protected by mLock 271 mutable Mutex mLock; 272 DefaultKeyedVector<int, SensorRecord*> mActiveSensors; 273 DefaultKeyedVector<int, SensorInterface*> mActiveVirtualSensors; 274 SortedVector< wp<SensorEventConnection> > mActiveConnections; 275 bool mWakeLockAcquired; 276 sensors_event_t *mSensorEventBuffer, *mSensorEventScratch; 277 SensorEventConnection const **mMapFlushEventsToConnections; 278 279 // The size of this vector is constant, only the items are mutable 280 KeyedVector<int32_t, sensors_event_t> mLastEventSeen; 281 282 public: 283 void cleanupConnection(SensorEventConnection* connection); 284 status_t enable(const sp<SensorEventConnection>& connection, int handle, 285 nsecs_t samplingPeriodNs, nsecs_t maxBatchReportLatencyNs, int reservedFlags); 286 status_t disable(const sp<SensorEventConnection>& connection, int handle); 287 status_t setEventRate(const sp<SensorEventConnection>& connection, int handle, nsecs_t ns); 288 status_t flushSensor(const sp<SensorEventConnection>& connection); 289 }; 290 291 // --------------------------------------------------------------------------- 292 }; // namespace android 293 294 #endif // ANDROID_SENSOR_SERVICE_H 295