• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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_EVENT_CONNECTION_H
18 #define ANDROID_SENSOR_EVENT_CONNECTION_H
19 
20 #include <atomic>
21 #include <stdint.h>
22 #include <sys/types.h>
23 #include <unordered_map>
24 
25 #include <utils/Vector.h>
26 #include <utils/SortedVector.h>
27 #include <utils/threads.h>
28 #include <utils/AndroidThreads.h>
29 #include <utils/RefBase.h>
30 #include <utils/Looper.h>
31 #include <utils/String8.h>
32 
33 #include <binder/BinderService.h>
34 
35 #include <sensor/Sensor.h>
36 #include <sensor/BitTube.h>
37 #include <sensor/ISensorServer.h>
38 #include <sensor/ISensorEventConnection.h>
39 
40 #include "SensorService.h"
41 
42 namespace android {
43 
44 class SensorService;
45 
46 class SensorService::SensorEventConnection:
47     public BnSensorEventConnection, public LooperCallback {
48 
49     friend class SensorService;
50 
51 public:
52     SensorEventConnection(const sp<SensorService>& service, uid_t uid, String8 packageName,
53                           bool isDataInjectionMode, const String16& opPackageName,
54                           const String16& attributionTag);
55 
56     status_t sendEvents(sensors_event_t const* buffer, size_t count, sensors_event_t* scratch,
57                         wp<const SensorEventConnection> const * mapFlushEventsToConnections = nullptr);
58     bool hasSensor(int32_t handle) const;
59     bool hasAnySensor() const;
60     bool hasOneShotSensors() const;
61     bool addSensor(int32_t handle);
62     bool removeSensor(int32_t handle);
63     std::vector<int32_t> getActiveSensorHandles() const;
64     void setFirstFlushPending(int32_t handle, bool value);
65     void dump(String8& result);
66     void dump(util::ProtoOutputStream* proto) const;
67     bool needsWakeLock();
68     void resetWakeLockRefCount();
69     String8 getPackageName() const;
70 
getUid()71     uid_t getUid() const { return mUid; }
72     // cap/uncap existing connection depending on the state of the mic toggle.
73     void onMicSensorAccessChanged(bool isMicToggleOn);
getUserId()74     userid_t getUserId() const { return mUserId; }
75 
76 private:
77     virtual ~SensorEventConnection();
78     virtual void onFirstRef();
79     virtual sp<BitTube> getSensorChannel() const;
80     virtual status_t enableDisable(int handle, bool enabled, nsecs_t samplingPeriodNs,
81                                    nsecs_t maxBatchReportLatencyNs, int reservedFlags);
82     virtual status_t setEventRate(int handle, nsecs_t samplingPeriodNs);
83     virtual status_t flush();
84     virtual int32_t configureChannel(int handle, int rateLevel);
85     virtual void destroy();
86 
87     // Count the number of flush complete events which are about to be dropped in the buffer.
88     // Increment mPendingFlushEventsToSend in mSensorInfo. These flush complete events will be sent
89     // separately before the next batch of events.
90     void countFlushCompleteEventsLocked(sensors_event_t const* scratch, int numEventsDropped);
91 
92     // Check if there are any wake up events in the buffer. If yes, return the index of the first
93     // wake_up sensor event in the buffer else return -1.  This wake_up sensor event will have the
94     // flag WAKE_UP_SENSOR_EVENT_NEEDS_ACK set. Exactly one event per packet will have the wake_up
95     // flag set. SOCK_SEQPACKET ensures that either the entire packet is read or 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 method
100     // 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 this
107     // connection. Wake up and non-wake up sensors have separate FIFOs but FIFO may be shared
108     // 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     // Add the events to the cache. If the cache would be exceeded, drop events at the beginning of
116     // the cache.
117     void appendEventsToCacheLocked(sensors_event_t const* events, int count);
118 
119     // LooperCallback method. If there is data to read on this fd, it is an ack from the app that it
120     // has read events from a wake up sensor, decrement mWakeLockRefCount.  If this fd is available
121     // for writing send the data from the cache.
122     virtual int handleEvent(int fd, int events, void* data);
123 
124     // Increment mPendingFlushEventsToSend for the given handle if the connection has sensor access.
125     // Returns true if this connection does have sensor access.
126     bool incrementPendingFlushCountIfHasAccess(int32_t handle);
127 
128     // Add or remove the file descriptor associated with the BitTube to the looper. If mDead is set
129     // to true or there are no more sensors for this connection, the file descriptor is removed if
130     // it has been previously added to the Looper. Depending on the state of the connection FD may
131     // be added to the Looper. The flags to set are determined by the internal state of the
132     // connection. FDs are added to the looper when wake-up sensors are registered (to poll for
133     // acknowledgements) and when write fails on the socket when there are too many error and the
134     // other end hangs up or when this client unregisters for this connection.
135     void updateLooperRegistration(const sp<Looper>& looper); void
136             updateLooperRegistrationLocked(const sp<Looper>& looper);
137 
138     // Returns whether sensor access is available based on both the uid being active and sensor
139     // privacy not being enabled.
140     bool hasSensorAccess();
141 
142     // Call noteOp for the sensor if the sensor requires a permission
143     bool noteOpIfRequired(const sensors_event_t& event);
144     // Limits all active connections when the mic toggle is flipped to on.
145     void capRates();
146     // Recover sensor connection previously capped by capRates().
147     void uncapRates();
148     sp<SensorService> const mService;
149     sp<BitTube> mChannel;
150     uid_t mUid;
151     std::atomic_bool mIsRateCappedBasedOnPermission;
152     mutable Mutex mConnectionLock;
153     // Number of events from wake up sensors which are still pending and haven't been delivered to
154     // the corresponding application. It is incremented by one unit for each write to the socket.
155     uint32_t mWakeLockRefCount;
156 
157     // If this flag is set to true, it means that the file descriptor associated with the BitTube
158     // has been added to the Looper in SensorService. This flag is typically set when this
159     // connection has wake-up sensors associated with it or when write has failed on this connection
160     // and we're storing some events in the cache.
161     bool mHasLooperCallbacks;
162     // If there are any errors associated with the Looper this flag is set to true and
163     // mWakeLockRefCount is reset to zero. needsWakeLock method will always return false, if this
164     // flag is set.
165     bool mDead;
166 
167     bool mDataInjectionMode;
168     struct FlushInfo {
169         // The number of flush complete events dropped for this sensor is stored here.  They are
170         // sent separately before the next batch of events.
171         int mPendingFlushEventsToSend;
172 
173         // Every activate is preceded by a flush. Only after the first flush complete is received,
174         // the events for the sensor are sent on that *connection*.
175         bool mFirstFlushPending;
176 
FlushInfoFlushInfo177         FlushInfo() : mPendingFlushEventsToSend(0), mFirstFlushPending(false) {}
178     };
179     // protected by SensorService::mLock. Key for this map is the sensor handle.
180     std::unordered_map<int32_t, FlushInfo> mSensorInfo;
181 
182     sensors_event_t *mEventCache;
183     int mCacheSize, mMaxCacheSize;
184     int64_t mTimeOfLastEventDrop;
185     int mEventsDropped;
186     String8 mPackageName;
187     const String16 mOpPackageName;
188     const String16 mAttributionTag;
189     int mTargetSdk;
190 #if DEBUG_CONNECTIONS
191     int mEventsReceived, mEventsSent, mEventsSentFromCache;
192     int mTotalAcksNeeded, mTotalAcksReceived;
193 #endif
194 
195     // Used to track if this object was inappropriately used after destroy().
196     std::atomic_bool mDestroyed;
197 
198     // Store a mapping of sensor handles to required AppOp for a sensor. This map only contains a
199     // valid mapping for sensors that require a permission in order to reduce the lookup time.
200     std::unordered_map<int32_t, int32_t> mHandleToAppOp;
201     // Mapping of sensor handles to its rate before being capped by the mic toggle.
202     std::unordered_map<int, nsecs_t> mMicSamplingPeriodBackup;
203     userid_t mUserId;
204 };
205 
206 } // namepsace android
207 
208 #endif // ANDROID_SENSOR_EVENT_CONNECTION_H
209 
210