SensorService.h revision 8493b79e1cff92450076ca7450c4bf4e434a6816
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 48struct sensors_poll_device_t; 49struct sensors_module_t; 50 51namespace android { 52// --------------------------------------------------------------------------- 53 54class 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* 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 writeToSocketFromCacheLocked(); 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 sp<SensorService> const mService; 121 sp<BitTube> mChannel; 122 uid_t mUid; 123 mutable Mutex mConnectionLock; 124 // Number of events from wake up sensors which are still pending and haven't been delivered 125 // to the corresponding application. It is incremented by one unit for each write to the 126 // socket. 127 int mWakeLockRefCount; 128 129 struct FlushInfo { 130 // The number of flush complete events dropped for this sensor is stored here. 131 // They are sent separately before the next batch of events. 132 int mPendingFlushEventsToSend; 133 // Every activate is preceded by a flush. Only after the first flush complete is 134 // received, the events for the sensor are sent on that *connection*. 135 bool mFirstFlushPending; 136 FlushInfo() : mPendingFlushEventsToSend(0), mFirstFlushPending(false) {} 137 }; 138 // protected by SensorService::mLock. Key for this vector is the sensor handle. 139 KeyedVector<int, FlushInfo> mSensorInfo; 140 sensors_event_t *mEventCache; 141 int mCacheSize, mMaxCacheSize; 142 143#if DEBUG_CONNECTIONS 144 int mEventsReceived, mEventsSent, mEventsSentFromCache; 145 int mTotalAcksNeeded, mTotalAcksReceived; 146#endif 147 148 public: 149 SensorEventConnection(const sp<SensorService>& service, uid_t uid); 150 151 status_t sendEvents(sensors_event_t* buffer, size_t count, 152 sensors_event_t* scratch, 153 SensorEventConnection const * const * mapFlushEventsToConnections = NULL); 154 bool hasSensor(int32_t handle) const; 155 bool hasAnySensor() const; 156 bool hasOneShotSensors() const; 157 bool addSensor(int32_t handle); 158 bool removeSensor(int32_t handle); 159 void setFirstFlushPending(int32_t handle, bool value); 160 void dump(String8& result); 161 bool needsWakeLock(); 162 163 uid_t getUid() const { return mUid; } 164 }; 165 166 class SensorRecord { 167 SortedVector< wp<SensorEventConnection> > mConnections; 168 // A queue of all flush() calls made on this sensor. Flush complete events will be 169 // sent in this order. 170 Vector< wp<SensorEventConnection> > mPendingFlushConnections; 171 public: 172 SensorRecord(const sp<SensorEventConnection>& connection); 173 bool addConnection(const sp<SensorEventConnection>& connection); 174 bool removeConnection(const wp<SensorEventConnection>& connection); 175 size_t getNumConnections() const { return mConnections.size(); } 176 177 void addPendingFlushConnection(const sp<SensorEventConnection>& connection); 178 void removeFirstPendingFlushConnection(); 179 SensorEventConnection * getFirstPendingFlushConnection(); 180 }; 181 182 class SensorEventAckReceiver : public Thread { 183 sp<SensorService> const mService; 184 public: 185 virtual bool threadLoop(); 186 SensorEventAckReceiver(const sp<SensorService>& service): mService(service) {} 187 }; 188 189 String8 getSensorName(int handle) const; 190 bool isVirtualSensor(int handle) const; 191 Sensor getSensorFromHandle(int handle) const; 192 bool isWakeUpSensor(int type) const; 193 void recordLastValueLocked(const sensors_event_t* buffer, size_t count); 194 static void sortEventBuffer(sensors_event_t* buffer, size_t count); 195 Sensor registerSensor(SensorInterface* sensor); 196 Sensor registerVirtualSensor(SensorInterface* sensor); 197 status_t cleanupWithoutDisable( 198 const sp<SensorEventConnection>& connection, int handle); 199 status_t cleanupWithoutDisableLocked( 200 const sp<SensorEventConnection>& connection, int handle); 201 void cleanupAutoDisabledSensorLocked(const sp<SensorEventConnection>& connection, 202 sensors_event_t const* buffer, const int count); 203 static bool canAccessSensor(const Sensor& sensor); 204 static bool verifyCanAccessSensor(const Sensor& sensor, const char* operation); 205 // SensorService acquires a partial wakelock for delivering events from wake up sensors. This 206 // method checks whether all the events from these wake up sensors have been delivered to the 207 // corresponding applications, if yes the wakelock is released. 208 void checkWakeLockState(); 209 void checkWakeLockStateLocked(); 210 bool isWakeUpSensorEvent(const sensors_event_t& event) const; 211 212 SensorRecord * getSensorRecord(int handle); 213 214 sp<Looper> getLooper() const; 215 216 // constants 217 Vector<Sensor> mSensorList; 218 Vector<Sensor> mUserSensorListDebug; 219 Vector<Sensor> mUserSensorList; 220 DefaultKeyedVector<int, SensorInterface*> mSensorMap; 221 Vector<SensorInterface *> mVirtualSensorList; 222 status_t mInitCheck; 223 // Socket buffersize used to initialize BitTube. This size depends on whether batching is 224 // supported or not. 225 size_t mSocketBufferSize; 226 sp<Looper> mLooper; 227 228 // protected by mLock 229 mutable Mutex mLock; 230 DefaultKeyedVector<int, SensorRecord*> mActiveSensors; 231 DefaultKeyedVector<int, SensorInterface*> mActiveVirtualSensors; 232 SortedVector< wp<SensorEventConnection> > mActiveConnections; 233 bool mWakeLockAcquired; 234 sensors_event_t *mSensorEventBuffer, *mSensorEventScratch; 235 SensorEventConnection const **mMapFlushEventsToConnections; 236 237 // The size of this vector is constant, only the items are mutable 238 KeyedVector<int32_t, sensors_event_t> mLastEventSeen; 239 240public: 241 void cleanupConnection(SensorEventConnection* connection); 242 status_t enable(const sp<SensorEventConnection>& connection, int handle, 243 nsecs_t samplingPeriodNs, nsecs_t maxBatchReportLatencyNs, int reservedFlags); 244 status_t disable(const sp<SensorEventConnection>& connection, int handle); 245 status_t setEventRate(const sp<SensorEventConnection>& connection, int handle, nsecs_t ns); 246 status_t flushSensor(const sp<SensorEventConnection>& connection); 247}; 248 249// --------------------------------------------------------------------------- 250}; // namespace android 251 252#endif // ANDROID_SENSOR_SERVICE_H 253