/* * Copyright (C) 2010 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef ANDROID_SENSOR_SERVICE_H #define ANDROID_SENSOR_SERVICE_H #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "SensorInterface.h" // --------------------------------------------------------------------------- #define DEBUG_CONNECTIONS false // Max size is 100 KB which is enough to accept a batch of about 1000 events. #define MAX_SOCKET_BUFFER_SIZE_BATCHED 100 * 1024 // For older HALs which don't support batching, use a smaller socket buffer size. #define SOCKET_BUFFER_SIZE_NON_BATCHED 4 * 1024 struct sensors_poll_device_t; struct sensors_module_t; namespace android { // --------------------------------------------------------------------------- class SensorService : public BinderService, public BnSensorServer, protected Thread { friend class BinderService; static const char* WAKE_LOCK_NAME; static char const* getServiceName() ANDROID_API { return "sensorservice"; } SensorService() ANDROID_API; virtual ~SensorService(); virtual void onFirstRef(); // Thread interface virtual bool threadLoop(); // ISensorServer interface virtual Vector getSensorList(); virtual sp createSensorEventConnection(); virtual status_t dump(int fd, const Vector& args); class SensorEventConnection : public BnSensorEventConnection, public LooperCallback { friend class SensorService; virtual ~SensorEventConnection(); virtual void onFirstRef(); virtual sp getSensorChannel() const; virtual status_t enableDisable(int handle, bool enabled, nsecs_t samplingPeriodNs, nsecs_t maxBatchReportLatencyNs, int reservedFlags); virtual status_t setEventRate(int handle, nsecs_t samplingPeriodNs); virtual status_t flush(); // Count the number of flush complete events which are about to be dropped in the buffer. // Increment mPendingFlushEventsToSend in mSensorInfo. These flush complete events will be // sent separately before the next batch of events. void countFlushCompleteEventsLocked(sensors_event_t const* scratch, int numEventsDropped); // Check if there are any wake up events in the buffer. If yes, return the index of the // first wake_up sensor event in the buffer else return -1. This wake_up sensor event will // have the flag WAKE_UP_SENSOR_EVENT_NEEDS_ACK set. Exactly one event per packet will have // the wake_up flag set. SOCK_SEQPACKET ensures that either the entire packet is read or // dropped. int findWakeUpSensorEventLocked(sensors_event_t const* scratch, int count); // Send pending flush_complete events. There may have been flush_complete_events that are // dropped which need to be sent separately before other events. On older HALs (1_0) this // method emulates the behavior of flush(). void sendPendingFlushEventsLocked(); // Writes events from mEventCache to the socket. void writeToSocketFromCache(); // Compute the approximate cache size from the FIFO sizes of various sensors registered for // this connection. Wake up and non-wake up sensors have separate FIFOs but FIFO may be // shared amongst wake-up sensors and non-wake up sensors. int computeMaxCacheSizeLocked() const; // When more sensors register, the maximum cache size desired may change. Compute max cache // size, reallocate memory and copy over events from the older cache. void reAllocateCacheLocked(sensors_event_t const* scratch, int count); // LooperCallback method. If there is data to read on this fd, it is an ack from the // app that it has read events from a wake up sensor, decrement mWakeLockRefCount. // If this fd is available for writing send the data from the cache. virtual int handleEvent(int fd, int events, void* data); // Increment mPendingFlushEventsToSend for the given sensor handle. void incrementPendingFlushCount(int32_t handle); // Add or remove the file descriptor associated with the BitTube to the looper. If mDead is // set to true or there are no more sensors for this connection, the file descriptor is // removed if it has been previously added to the Looper. Depending on the state of the // connection FD may be added to the Looper. The flags to set are determined by the internal // state of the connection. FDs are added to the looper when wake-up sensors are registered // (to poll for acknowledgements) and when write fails on the socket when there are too many // events (to poll when the FD is available for writing). FDs are removed when there is an // error and the other end hangs up or when this client unregisters for this connection. void updateLooperRegistration(const sp& looper); void updateLooperRegistrationLocked(const sp& looper); sp const mService; sp mChannel; uid_t mUid; mutable Mutex mConnectionLock; // Number of events from wake up sensors which are still pending and haven't been delivered // to the corresponding application. It is incremented by one unit for each write to the // socket. uint32_t mWakeLockRefCount; // If this flag is set to true, it means that the file descriptor associated with the // BitTube has been added to the Looper in SensorService. This flag is typically set when // this connection has wake-up sensors associated with it or when write has failed on this // connection and we're storing some events in the cache. bool mHasLooperCallbacks; // If there are any errors associated with the Looper this flag is set to true and // mWakeLockRefCount is reset to zero. needsWakeLock method will always return false, if // this flag is set. bool mDead; struct FlushInfo { // The number of flush complete events dropped for this sensor is stored here. // They are sent separately before the next batch of events. int mPendingFlushEventsToSend; // Every activate is preceded by a flush. Only after the first flush complete is // received, the events for the sensor are sent on that *connection*. bool mFirstFlushPending; FlushInfo() : mPendingFlushEventsToSend(0), mFirstFlushPending(false) {} }; // protected by SensorService::mLock. Key for this vector is the sensor handle. KeyedVector mSensorInfo; sensors_event_t *mEventCache; int mCacheSize, mMaxCacheSize; #if DEBUG_CONNECTIONS int mEventsReceived, mEventsSent, mEventsSentFromCache; int mTotalAcksNeeded, mTotalAcksReceived; #endif public: SensorEventConnection(const sp& service, uid_t uid); status_t sendEvents(sensors_event_t const* buffer, size_t count, sensors_event_t* scratch, SensorEventConnection const * const * mapFlushEventsToConnections = NULL); bool hasSensor(int32_t handle) const; bool hasAnySensor() const; bool hasOneShotSensors() const; bool addSensor(int32_t handle); bool removeSensor(int32_t handle); void setFirstFlushPending(int32_t handle, bool value); void dump(String8& result); bool needsWakeLock(); void resetWakeLockRefCount(); uid_t getUid() const { return mUid; } }; class SensorRecord { SortedVector< wp > mConnections; // A queue of all flush() calls made on this sensor. Flush complete events will be // sent in this order. Vector< wp > mPendingFlushConnections; public: SensorRecord(const sp& connection); bool addConnection(const sp& connection); bool removeConnection(const wp& connection); size_t getNumConnections() const { return mConnections.size(); } void addPendingFlushConnection(const sp& connection); void removeFirstPendingFlushConnection(); SensorEventConnection * getFirstPendingFlushConnection(); }; class SensorEventAckReceiver : public Thread { sp const mService; public: virtual bool threadLoop(); SensorEventAckReceiver(const sp& service): mService(service) {} }; String8 getSensorName(int handle) const; bool isVirtualSensor(int handle) const; Sensor getSensorFromHandle(int handle) const; bool isWakeUpSensor(int type) const; void recordLastValueLocked(sensors_event_t const* buffer, size_t count); static void sortEventBuffer(sensors_event_t* buffer, size_t count); Sensor registerSensor(SensorInterface* sensor); Sensor registerVirtualSensor(SensorInterface* sensor); status_t cleanupWithoutDisable( const sp& connection, int handle); status_t cleanupWithoutDisableLocked( const sp& connection, int handle); void cleanupAutoDisabledSensorLocked(const sp& connection, sensors_event_t const* buffer, const int count); static bool canAccessSensor(const Sensor& sensor); static bool verifyCanAccessSensor(const Sensor& sensor, const char* operation); // SensorService acquires a partial wakelock for delivering events from wake up sensors. This // method checks whether all the events from these wake up sensors have been delivered to the // corresponding applications, if yes the wakelock is released. void checkWakeLockState(); void checkWakeLockStateLocked(); bool isWakeLockAcquired(); bool isWakeUpSensorEvent(const sensors_event_t& event) const; SensorRecord * getSensorRecord(int handle); sp getLooper() const; // Reset mWakeLockRefCounts for all SensorEventConnections to zero. This may happen if // SensorService did not receive any acknowledgements from apps which have registered for // wake_up sensors. void resetAllWakeLockRefCounts(); // Acquire or release wake_lock. If wake_lock is acquired, set the timeout in the looper to // 5 seconds and wake the looper. void setWakeLockAcquiredLocked(bool acquire); // Send events from the event cache for this particular connection. void sendEventsFromCache(const sp& connection); // Promote all weak referecences in mActiveConnections vector to strong references and add them // to the output vector. void populateActiveConnections(SortedVector< sp >* activeConnections); // constants Vector mSensorList; Vector mUserSensorListDebug; Vector mUserSensorList; DefaultKeyedVector mSensorMap; Vector mVirtualSensorList; status_t mInitCheck; // Socket buffersize used to initialize BitTube. This size depends on whether batching is // supported or not. uint32_t mSocketBufferSize; sp mLooper; sp mAckReceiver; // protected by mLock mutable Mutex mLock; DefaultKeyedVector mActiveSensors; DefaultKeyedVector mActiveVirtualSensors; SortedVector< wp > mActiveConnections; bool mWakeLockAcquired; sensors_event_t *mSensorEventBuffer, *mSensorEventScratch; SensorEventConnection const **mMapFlushEventsToConnections; // The size of this vector is constant, only the items are mutable KeyedVector mLastEventSeen; public: void cleanupConnection(SensorEventConnection* connection); status_t enable(const sp& connection, int handle, nsecs_t samplingPeriodNs, nsecs_t maxBatchReportLatencyNs, int reservedFlags); status_t disable(const sp& connection, int handle); status_t setEventRate(const sp& connection, int handle, nsecs_t ns); status_t flushSensor(const sp& connection); }; // --------------------------------------------------------------------------- }; // namespace android #endif // ANDROID_SENSOR_SERVICE_H