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 /**
18  * Structures and functions to receive and process sensor events in
19  * native code.
20  *
21  * @addtogroup Sensor
22  * @{
23  */
24 
25 /**
26  * @file sensor.h
27  */
28 
29 #ifndef ANDROID_SENSOR_H
30 #define ANDROID_SENSOR_H
31 
32 #include <sys/cdefs.h>
33 
34 /******************************************************************
35  *
36  * IMPORTANT NOTICE:
37  *
38  *   This file is part of Android's set of stable system headers
39  *   exposed by the Android NDK (Native Development Kit).
40  *
41  *   Third-party source AND binary code relies on the definitions
42  *   here to be FROZEN ON ALL UPCOMING PLATFORM RELEASES.
43  *
44  *   - DO NOT MODIFY ENUMS (EXCEPT IF YOU ADD NEW 32-BIT VALUES)
45  *   - DO NOT MODIFY CONSTANTS OR FUNCTIONAL MACROS
46  *   - DO NOT CHANGE THE SIGNATURE OF FUNCTIONS IN ANY WAY
47  *   - DO NOT CHANGE THE LAYOUT OR SIZE OF STRUCTURES
48  */
49 
50 #include <android/looper.h>
51 
52 #include <stdbool.h>
53 #include <sys/types.h>
54 #include <math.h>
55 #include <stdint.h>
56 
57 // This file may also be built on glibc or on Windows/MacOS libc's, so no-op
58 // and deprecated definitions are provided.
59 #if !defined(__INTRODUCED_IN)
60 #define __INTRODUCED_IN(__api_level) /* nothing */
61 #endif
62 #if !defined(__DEPRECATED_IN)
63 #define __DEPRECATED_IN(__api_level, msg) __attribute__((__deprecated__(msg)))
64 #endif
65 
66 #ifdef __cplusplus
67 extern "C" {
68 #endif
69 
70 typedef struct AHardwareBuffer AHardwareBuffer;
71 
72 #define ASENSOR_RESOLUTION_INVALID     (nanf(""))
73 #define ASENSOR_FIFO_COUNT_INVALID     (-1)
74 #define ASENSOR_DELAY_INVALID          INT32_MIN
75 #define ASENSOR_INVALID                (-1)
76 
77 /* (Keep in sync with hardware/sensors-base.h and Sensor.java.) */
78 
79 /**
80  * Sensor types.
81  *
82  * See
83  * [android.hardware.SensorEvent#values](https://developer.android.com/reference/android/hardware/SensorEvent.html#values)
84  * for detailed explanations of the data returned for each of these types.
85  */
86 enum {
87     /**
88      * Invalid sensor type. Returned by {@link ASensor_getType} as error value.
89      */
90     ASENSOR_TYPE_INVALID = -1,
91     /**
92      * {@link ASENSOR_TYPE_ACCELEROMETER}
93      * reporting-mode: continuous
94      *
95      *  All values are in SI units (m/s^2) and measure the acceleration of the
96      *  device minus the force of gravity.
97      */
98     ASENSOR_TYPE_ACCELEROMETER       = 1,
99     /**
100      * {@link ASENSOR_TYPE_MAGNETIC_FIELD}
101      * reporting-mode: continuous
102      *
103      *  All values are in micro-Tesla (uT) and measure the geomagnetic
104      *  field in the X, Y and Z axis.
105      */
106     ASENSOR_TYPE_MAGNETIC_FIELD      = 2,
107     /**
108      * {@link ASENSOR_TYPE_GYROSCOPE}
109      * reporting-mode: continuous
110      *
111      *  All values are in radians/second and measure the rate of rotation
112      *  around the X, Y and Z axis.
113      */
114     ASENSOR_TYPE_GYROSCOPE           = 4,
115     /**
116      * {@link ASENSOR_TYPE_LIGHT}
117      * reporting-mode: on-change
118      *
119      * The light sensor value is returned in SI lux units.
120      */
121     ASENSOR_TYPE_LIGHT               = 5,
122     /**
123      * {@link ASENSOR_TYPE_PRESSURE}
124      *
125      * The pressure sensor value is returned in hPa (millibar).
126      */
127     ASENSOR_TYPE_PRESSURE            = 6,
128     /**
129      * {@link ASENSOR_TYPE_PROXIMITY}
130      * reporting-mode: on-change
131      *
132      * The proximity sensor which turns the screen off and back on during calls is the
133      * wake-up proximity sensor. Implement wake-up proximity sensor before implementing
134      * a non wake-up proximity sensor. For the wake-up proximity sensor set the flag
135      * SENSOR_FLAG_WAKE_UP.
136      * The value corresponds to the distance to the nearest object in centimeters.
137      */
138     ASENSOR_TYPE_PROXIMITY           = 8,
139     /**
140      * {@link ASENSOR_TYPE_GRAVITY}
141      *
142      * All values are in SI units (m/s^2) and measure the direction and
143      * magnitude of gravity. When the device is at rest, the output of
144      * the gravity sensor should be identical to that of the accelerometer.
145      */
146     ASENSOR_TYPE_GRAVITY             = 9,
147     /**
148      * {@link ASENSOR_TYPE_LINEAR_ACCELERATION}
149      * reporting-mode: continuous
150      *
151      *  All values are in SI units (m/s^2) and measure the acceleration of the
152      *  device not including the force of gravity.
153      */
154     ASENSOR_TYPE_LINEAR_ACCELERATION = 10,
155     /**
156      * {@link ASENSOR_TYPE_ROTATION_VECTOR}
157      */
158     ASENSOR_TYPE_ROTATION_VECTOR     = 11,
159     /**
160      * {@link ASENSOR_TYPE_RELATIVE_HUMIDITY}
161      *
162      * The relative humidity sensor value is returned in percent.
163      */
164     ASENSOR_TYPE_RELATIVE_HUMIDITY   = 12,
165     /**
166      * {@link ASENSOR_TYPE_AMBIENT_TEMPERATURE}
167      *
168      * The ambient temperature sensor value is returned in Celcius.
169      */
170     ASENSOR_TYPE_AMBIENT_TEMPERATURE = 13,
171     /**
172      * {@link ASENSOR_TYPE_MAGNETIC_FIELD_UNCALIBRATED}
173      */
174     ASENSOR_TYPE_MAGNETIC_FIELD_UNCALIBRATED = 14,
175     /**
176      * {@link ASENSOR_TYPE_GAME_ROTATION_VECTOR}
177      */
178     ASENSOR_TYPE_GAME_ROTATION_VECTOR = 15,
179     /**
180      * {@link ASENSOR_TYPE_GYROSCOPE_UNCALIBRATED}
181      */
182     ASENSOR_TYPE_GYROSCOPE_UNCALIBRATED = 16,
183     /**
184      * {@link ASENSOR_TYPE_SIGNIFICANT_MOTION}
185      */
186     ASENSOR_TYPE_SIGNIFICANT_MOTION = 17,
187     /**
188      * {@link ASENSOR_TYPE_STEP_DETECTOR}
189      */
190     ASENSOR_TYPE_STEP_DETECTOR = 18,
191     /**
192      * {@link ASENSOR_TYPE_STEP_COUNTER}
193      */
194     ASENSOR_TYPE_STEP_COUNTER = 19,
195     /**
196      * {@link ASENSOR_TYPE_GEOMAGNETIC_ROTATION_VECTOR}
197      */
198     ASENSOR_TYPE_GEOMAGNETIC_ROTATION_VECTOR = 20,
199     /**
200      * {@link ASENSOR_TYPE_HEART_RATE}
201      */
202     ASENSOR_TYPE_HEART_RATE = 21,
203     /**
204      * {@link ASENSOR_TYPE_POSE_6DOF}
205      */
206     ASENSOR_TYPE_POSE_6DOF = 28,
207     /**
208      * {@link ASENSOR_TYPE_STATIONARY_DETECT}
209      */
210     ASENSOR_TYPE_STATIONARY_DETECT = 29,
211     /**
212      * {@link ASENSOR_TYPE_MOTION_DETECT}
213      */
214     ASENSOR_TYPE_MOTION_DETECT = 30,
215     /**
216      * {@link ASENSOR_TYPE_HEART_BEAT}
217      */
218     ASENSOR_TYPE_HEART_BEAT = 31,
219     /**
220      * A constant describing a dynamic sensor meta event sensor.
221      *
222      * A sensor event of this type is received when a dynamic sensor is added to or removed from
223      * the system. This sensor type should always use special trigger report mode.
224      */
225     ASENSOR_TYPE_DYNAMIC_SENSOR_META = 32,
226     /**
227      * This sensor type is for delivering additional sensor information aside
228      * from sensor event data.
229      *
230      * Additional information may include:
231      *     - {@link ASENSOR_ADDITIONAL_INFO_INTERNAL_TEMPERATURE}
232      *     - {@link ASENSOR_ADDITIONAL_INFO_SAMPLING}
233      *     - {@link ASENSOR_ADDITIONAL_INFO_SENSOR_PLACEMENT}
234      *     - {@link ASENSOR_ADDITIONAL_INFO_UNTRACKED_DELAY}
235      *     - {@link ASENSOR_ADDITIONAL_INFO_VEC3_CALIBRATION}
236      *
237      * This type will never bind to a sensor. In other words, no sensor in the
238      * sensor list can have the type {@link ASENSOR_TYPE_ADDITIONAL_INFO}.
239      *
240      * If a device supports the sensor additional information feature, it will
241      * report additional information events via {@link ASensorEvent} and will
242      * have the type of {@link ASensorEvent} set to
243      * {@link ASENSOR_TYPE_ADDITIONAL_INFO} and the sensor of {@link ASensorEvent} set
244      * to the handle of the reporting sensor.
245      *
246      * Additional information reports consist of multiple frames ordered by
247      * {@link ASensorEvent#timestamp}. The first frame in the report will have
248      * a {@link AAdditionalInfoEvent#type} of
249      * {@link ASENSOR_ADDITIONAL_INFO_BEGIN}, and the last frame in the report
250      * will have a {@link AAdditionalInfoEvent#type} of
251      * {@link ASENSOR_ADDITIONAL_INFO_END}.
252      *
253      */
254     ASENSOR_TYPE_ADDITIONAL_INFO = 33,
255     /**
256      * {@link ASENSOR_TYPE_LOW_LATENCY_OFFBODY_DETECT}
257      */
258     ASENSOR_TYPE_LOW_LATENCY_OFFBODY_DETECT = 34,
259     /**
260      * {@link ASENSOR_TYPE_ACCELEROMETER_UNCALIBRATED}
261      */
262     ASENSOR_TYPE_ACCELEROMETER_UNCALIBRATED = 35,
263     /**
264      * {@link ASENSOR_TYPE_HINGE_ANGLE}
265      * reporting-mode: on-change
266      *
267      * The hinge angle sensor value is returned in degrees.
268      */
269     ASENSOR_TYPE_HINGE_ANGLE = 36,
270     /**
271      * {@link ASENSOR_TYPE_HEAD_TRACKER}
272      * reporting-mode: continuous
273      *
274      * Measures the orientation and rotational velocity of a user's head. Only for internal use
275      * within the Android system.
276      */
277     ASENSOR_TYPE_HEAD_TRACKER = 37,
278     /**
279      * {@link ASENSOR_TYPE_ACCELEROMETER_LIMITED_AXES}
280      * reporting-mode: continuous
281      *
282      * The first three values are in SI units (m/s^2) and measure the acceleration of the device
283      * minus the force of gravity. The last three values indicate which acceleration axes are
284      * supported. A value of 1.0 means supported and a value of 0 means not supported.
285      */
286     ASENSOR_TYPE_ACCELEROMETER_LIMITED_AXES = 38,
287     /**
288      * {@link ASENSOR_TYPE_GYROSCOPE_LIMITED_AXES}
289      * reporting-mode: continuous
290      *
291      * The first three values are in radians/second and measure the rate of rotation around the X,
292      * Y and Z axis. The last three values indicate which rotation axes are supported. A value of
293      * 1.0 means supported and a value of 0 means not supported.
294      */
295     ASENSOR_TYPE_GYROSCOPE_LIMITED_AXES = 39,
296     /**
297      * {@link ASENSOR_TYPE_ACCELEROMETER_LIMITED_AXES_UNCALIBRATED}
298      * reporting-mode: continuous
299      *
300      * The first three values are in SI units (m/s^2) and measure the acceleration of the device
301      * minus the force of gravity. The middle three values represent the estimated bias for each
302      * axis. The last three values indicate which acceleration axes are supported. A value of 1.0
303      * means supported and a value of 0 means not supported.
304      */
305     ASENSOR_TYPE_ACCELEROMETER_LIMITED_AXES_UNCALIBRATED = 40,
306     /**
307      * {@link ASENSOR_TYPE_GYROSCOPE_LIMITED_AXES_UNCALIBRATED}
308      * reporting-mode: continuous
309      *
310      * The first three values are in radians/second and measure the rate of rotation around the X,
311      * Y and Z axis. The middle three values represent the estimated drift around each axis in
312      * rad/s. The last three values indicate which rotation axes are supported. A value of 1.0 means
313      * supported and a value of 0 means not supported.
314      */
315     ASENSOR_TYPE_GYROSCOPE_LIMITED_AXES_UNCALIBRATED = 41,
316     /**
317      * {@link ASENSOR_TYPE_HEADING}
318      * reporting-mode: continuous
319      *
320      * A heading sensor measures the direction in which the device is pointing
321      * relative to true north in degrees.
322      */
323     ASENSOR_TYPE_HEADING = 42,
324 };
325 
326 /**
327  * Sensor accuracy measure.
328  */
329 enum {
330     /** no contact */
331     ASENSOR_STATUS_NO_CONTACT       = -1,
332     /** unreliable */
333     ASENSOR_STATUS_UNRELIABLE       = 0,
334     /** low accuracy */
335     ASENSOR_STATUS_ACCURACY_LOW     = 1,
336     /** medium accuracy */
337     ASENSOR_STATUS_ACCURACY_MEDIUM  = 2,
338     /** high accuracy */
339     ASENSOR_STATUS_ACCURACY_HIGH    = 3
340 };
341 
342 /**
343  * Sensor Reporting Modes.
344  */
345 enum {
346     /** invalid reporting mode */
347     AREPORTING_MODE_INVALID = -1,
348     /** continuous reporting */
349     AREPORTING_MODE_CONTINUOUS = 0,
350     /** reporting on change */
351     AREPORTING_MODE_ON_CHANGE = 1,
352     /** on shot reporting */
353     AREPORTING_MODE_ONE_SHOT = 2,
354     /** special trigger reporting */
355     AREPORTING_MODE_SPECIAL_TRIGGER = 3
356 };
357 
358 /**
359  * Sensor Direct Report Rates.
360  */
361 enum {
362     /** stopped */
363     ASENSOR_DIRECT_RATE_STOP = 0,
364     /** nominal 50Hz */
365     ASENSOR_DIRECT_RATE_NORMAL = 1,
366     /** nominal 200Hz */
367     ASENSOR_DIRECT_RATE_FAST = 2,
368     /** nominal 800Hz */
369     ASENSOR_DIRECT_RATE_VERY_FAST = 3
370 };
371 
372 /**
373  * Sensor Direct Channel Type.
374  */
375 enum {
376     /** shared memory created by ASharedMemory_create */
377     ASENSOR_DIRECT_CHANNEL_TYPE_SHARED_MEMORY = 1,
378     /** AHardwareBuffer */
379     ASENSOR_DIRECT_CHANNEL_TYPE_HARDWARE_BUFFER = 2
380 };
381 
382 /**
383  * Sensor Additional Info Types.
384  *
385  * Used to populate {@link AAdditionalInfoEvent#type}.
386  */
387 enum {
388     /** Marks the beginning of additional information frames */
389     ASENSOR_ADDITIONAL_INFO_BEGIN = 0,
390 
391     /** Marks the end of additional information frames */
392     ASENSOR_ADDITIONAL_INFO_END = 1,
393 
394     /**
395      * Estimation of the delay that is not tracked by sensor timestamps. This
396      * includes delay introduced by sensor front-end filtering, data transport,
397      * etc.
398      * float[2]: delay in seconds, standard deviation of estimated value
399      */
400     ASENSOR_ADDITIONAL_INFO_UNTRACKED_DELAY = 0x10000,
401 
402     /** float: Celsius temperature */
403     ASENSOR_ADDITIONAL_INFO_INTERNAL_TEMPERATURE,
404 
405     /**
406      * First three rows of a homogeneous matrix, which represents calibration to
407      * a three-element vector raw sensor reading.
408      * float[12]: 3x4 matrix in row major order
409      */
410     ASENSOR_ADDITIONAL_INFO_VEC3_CALIBRATION,
411 
412     /**
413      * Location and orientation of sensor element in the device frame: origin is
414      * the geometric center of the mobile device screen surface; the axis
415      * definition corresponds to Android sensor definitions.
416      * float[12]: 3x4 matrix in row major order
417      */
418     ASENSOR_ADDITIONAL_INFO_SENSOR_PLACEMENT,
419 
420     /**
421      * float[2]: raw sample period in seconds,
422      *           standard deviation of sampling period
423      */
424     ASENSOR_ADDITIONAL_INFO_SAMPLING,
425 };
426 
427 /*
428  * A few useful constants
429  */
430 
431 /** Earth's gravity in m/s^2 */
432 #define ASENSOR_STANDARD_GRAVITY            (9.80665f)
433 /** Maximum magnetic field on Earth's surface in uT */
434 #define ASENSOR_MAGNETIC_FIELD_EARTH_MAX    (60.0f)
435 /** Minimum magnetic field on Earth's surface in uT*/
436 #define ASENSOR_MAGNETIC_FIELD_EARTH_MIN    (30.0f)
437 
438 /**
439  * A sensor event.
440  */
441 
442 /* NOTE: changes to these structs have to be backward compatible */
443 typedef struct ASensorVector {
444     union {
445         float v[3];
446         struct {
447             float x;
448             float y;
449             float z;
450         };
451         struct {
452             float azimuth;
453             float pitch;
454             float roll;
455         };
456     };
457     int8_t status;
458     uint8_t reserved[3];
459 } ASensorVector;
460 
461 typedef struct AMetaDataEvent {
462     int32_t what;
463     int32_t sensor;
464 } AMetaDataEvent;
465 
466 typedef struct AUncalibratedEvent {
467     union {
468         float uncalib[3];
469         struct {
470             float x_uncalib;
471             float y_uncalib;
472             float z_uncalib;
473         };
474     };
475     union {
476         float bias[3];
477         struct {
478             float x_bias;
479             float y_bias;
480             float z_bias;
481         };
482     };
483 } AUncalibratedEvent;
484 
485 typedef struct AHeartRateEvent {
486     float bpm;
487     int8_t status;
488 } AHeartRateEvent;
489 
490 typedef struct ADynamicSensorEvent {
491     int32_t  connected;
492     int32_t  handle;
493 } ADynamicSensorEvent;
494 
495 typedef struct AAdditionalInfoEvent {
496     /**
497      * Event type, such as ASENSOR_ADDITIONAL_INFO_BEGIN, ASENSOR_ADDITIONAL_INFO_END and others.
498      * Refer to {@link ASENSOR_TYPE_ADDITIONAL_INFO} for the expected reporting behavior.
499      */
500     int32_t type;
501     int32_t serial;
502     union {
503         int32_t data_int32[14];
504         float   data_float[14];
505     };
506 } AAdditionalInfoEvent;
507 
508 typedef struct AHeadTrackerEvent {
509     /**
510      * The fields rx, ry, rz are an Euler vector (rotation vector, i.e. a vector
511      * whose direction indicates the axis of rotation and magnitude indicates
512      * the angle to rotate around that axis) representing the transform from
513      * the (arbitrary, possibly slowly drifting) reference frame to the
514      * head frame. Expressed in radians. Magnitude of the vector must be
515      * in the range [0, pi], while the value of individual axes are
516      * in the range [-pi, pi].
517      */
518     float rx;
519     float ry;
520     float rz;
521 
522     /**
523      * The fields vx, vy, vz are an Euler vector (rotation vector) representing
524      * the angular velocity of the head (relative to itself), in radians per
525      * second. The direction of this vector indicates the axis of rotation, and
526      * the magnitude indicates the rate of rotation.
527      */
528     float vx;
529     float vy;
530     float vz;
531 
532     /**
533      * This value changes each time the reference frame is suddenly and
534      * significantly changed, for example if an orientation filter algorithm
535      * used for determining the orientation has had its state reset.
536      */
537     int32_t discontinuity_count;
538 } AHeadTrackerEvent;
539 
540 typedef struct ALimitedAxesImuEvent {
541     union {
542         float calib[3];
543         struct {
544             float x;
545             float y;
546             float z;
547         };
548     };
549     union {
550         float supported[3];
551         struct {
552             float x_supported;
553             float y_supported;
554             float z_supported;
555         };
556     };
557 } ALimitedAxesImuEvent;
558 
559 typedef struct ALimitedAxesImuUncalibratedEvent {
560     union {
561         float uncalib[3];
562         struct {
563             float x_uncalib;
564             float y_uncalib;
565             float z_uncalib;
566         };
567     };
568     union {
569         float bias[3];
570         struct {
571             float x_bias;
572             float y_bias;
573             float z_bias;
574         };
575     };
576     union {
577         float supported[3];
578         struct {
579             float x_supported;
580             float y_supported;
581             float z_supported;
582         };
583     };
584 } ALimitedAxesImuUncalibratedEvent;
585 
586 typedef struct AHeadingEvent {
587     /**
588      * The direction in which the device is pointing relative to true north in
589      * degrees. The value must be between 0.0 (inclusive) and 360.0 (exclusive),
590      * with 0 indicating north, 90 east, 180 south, and 270 west.
591      */
592     float heading;
593     /**
594      * Accuracy is defined at 68% confidence. In the case where the underlying
595      * distribution is assumed Gaussian normal, this would be considered one
596      * standard deviation. For example, if the heading returns 60 degrees, and
597      * accuracy returns 10 degrees, then there is a 68 percent probability of
598      * the true heading being between 50 degrees and 70 degrees.
599      */
600     float accuracy;
601 } AHeadingEvent;
602 
603 // LINT.IfChange
604 /**
605  * Information that describes a sensor event, refer to
606  * <a href="/reference/android/hardware/SensorEvent">SensorEvent</a> for additional
607  * documentation.
608  *
609  * NOTE: changes to this struct has to be backward compatible and reflected in
610  * sensors_event_t
611  */
612 typedef struct ASensorEvent {
613     /* sizeof(struct ASensorEvent) */
614     int32_t version;
615     /** The sensor that generates this event */
616     int32_t sensor;
617     /** Sensor type for the event, such as {@link ASENSOR_TYPE_ACCELEROMETER} */
618     int32_t type;
619     /** do not use */
620     int32_t reserved0;
621     /**
622      * The time in nanoseconds at which the event happened, and its behavior
623      * is identical to <a href="/reference/android/hardware/SensorEvent#timestamp">
624      * SensorEvent::timestamp</a> in Java API.
625      */
626     int64_t timestamp;
627     union {
628         union {
629             float           data[16];
630             ASensorVector   vector;
631             ASensorVector   acceleration;
632             ASensorVector   gyro;
633             ASensorVector   magnetic;
634             float           temperature;
635             float           distance;
636             float           light;
637             float           pressure;
638             float           relative_humidity;
639             AUncalibratedEvent uncalibrated_acceleration;
640             AUncalibratedEvent uncalibrated_gyro;
641             AUncalibratedEvent uncalibrated_magnetic;
642             AMetaDataEvent meta_data;
643             AHeartRateEvent heart_rate;
644             ADynamicSensorEvent dynamic_sensor_meta;
645             AAdditionalInfoEvent additional_info;
646             AHeadTrackerEvent head_tracker;
647             ALimitedAxesImuEvent limited_axes_imu;
648             ALimitedAxesImuUncalibratedEvent limited_axes_imu_uncalibrated;
649             AHeadingEvent heading;
650         };
651         union {
652             uint64_t        data[8];
653             uint64_t        step_counter;
654         } u64;
655     };
656 
657     uint32_t flags;
658     int32_t reserved1[3];
659 } ASensorEvent;
660 // LINT.ThenChange(hardware/libhardware/include/hardware/sensors.h)
661 
662 struct ASensorManager;
663 /**
664  * {@link ASensorManager} is an opaque type to manage sensors and
665  * events queues.
666  *
667  * {@link ASensorManager} is a singleton that can be obtained using
668  * ASensorManager_getInstance().
669  *
670  * This file provides a set of functions that uses {@link
671  * ASensorManager} to access and list hardware sensors, and
672  * create and destroy event queues:
673  * - ASensorManager_getSensorList()
674  * - ASensorManager_getDefaultSensor()
675  * - ASensorManager_getDefaultSensorEx()
676  * - ASensorManager_createEventQueue()
677  * - ASensorManager_destroyEventQueue()
678  */
679 typedef struct ASensorManager ASensorManager;
680 
681 
682 struct ASensorEventQueue;
683 /**
684  * {@link ASensorEventQueue} is an opaque type that provides access to
685  * {@link ASensorEvent} from hardware sensors.
686  *
687  * A new {@link ASensorEventQueue} can be obtained using ASensorManager_createEventQueue().
688  *
689  * This file provides a set of functions to enable and disable
690  * sensors, check and get events, and set event rates on a {@link
691  * ASensorEventQueue}.
692  * - ASensorEventQueue_enableSensor()
693  * - ASensorEventQueue_disableSensor()
694  * - ASensorEventQueue_hasEvents()
695  * - ASensorEventQueue_getEvents()
696  * - ASensorEventQueue_setEventRate()
697  * - ASensorEventQueue_requestAdditionalInfoEvents()
698  */
699 typedef struct ASensorEventQueue ASensorEventQueue;
700 
701 struct ASensor;
702 /**
703  * {@link ASensor} is an opaque type that provides information about
704  * an hardware sensors.
705  *
706  * A {@link ASensor} pointer can be obtained using
707  * ASensorManager_getDefaultSensor(),
708  * ASensorManager_getDefaultSensorEx() or from a {@link ASensorList}.
709  *
710  * This file provides a set of functions to access properties of a
711  * {@link ASensor}:
712  * - ASensor_getName()
713  * - ASensor_getVendor()
714  * - ASensor_getType()
715  * - ASensor_getResolution()
716  * - ASensor_getMinDelay()
717  * - ASensor_getFifoMaxEventCount()
718  * - ASensor_getFifoReservedEventCount()
719  * - ASensor_getStringType()
720  * - ASensor_getReportingMode()
721  * - ASensor_isWakeUpSensor()
722  * - ASensor_getHandle()
723  */
724 typedef struct ASensor ASensor;
725 /**
726  * {@link ASensorRef} is a type for constant pointers to {@link ASensor}.
727  *
728  * This is used to define entry in {@link ASensorList} arrays.
729  */
730 typedef ASensor const* ASensorRef;
731 /**
732  * {@link ASensorList} is an array of reference to {@link ASensor}.
733  *
734  * A {@link ASensorList} can be initialized using ASensorManager_getSensorList().
735  */
736 typedef ASensorRef const* ASensorList;
737 
738 /*****************************************************************************/
739 
740 /**
741  * Get a reference to the sensor manager. ASensorManager is a singleton
742  * per package as different packages may have access to different sensors.
743  *
744  * Deprecated: Use ASensorManager_getInstanceForPackage(const char*) instead.
745  *
746  * Example:
747  *
748  *     ASensorManager* sensorManager = ASensorManager_getInstance();
749  *
750  */
751 ASensorManager* ASensorManager_getInstance()
752         __DEPRECATED_IN(26, "Use ASensorManager_getInstanceForPackage instead");
753 
754 /**
755  * Get a reference to the sensor manager. ASensorManager is a singleton
756  * per package as different packages may have access to different sensors.
757  *
758  * Example:
759  *
760  *     ASensorManager* sensorManager = ASensorManager_getInstanceForPackage("foo.bar.baz");
761  *
762  * Available since API level 26.
763  */
764 ASensorManager* ASensorManager_getInstanceForPackage(const char* packageName) __INTRODUCED_IN(26);
765 
766 /**
767  * Returns the list of available sensors. The returned list is owned by the
768  * sensor manager and will not change between calls to this function.
769  *
770  * \param manager the {@link ASensorManager} instance obtained from
771  *                {@link ASensorManager_getInstanceForPackage}.
772  * \param list    the returned list of sensors.
773  * \return positive number of returned sensors or negative error code.
774  *         BAD_VALUE: manager is NULL.
775  */
776 int ASensorManager_getSensorList(ASensorManager* manager, ASensorList* list);
777 
778 /**
779  * Returns the list of available dynamic sensors. If there are no dynamic
780  * sensors available, returns nullptr in list.
781  *
782  * Each time this is called, the previously returned list is deallocated and
783  * must no longer be used.
784  *
785  * Clients should call this if they receive a sensor update from
786  * {@link ASENSOR_TYPE_DYNAMIC_SENSOR_META} indicating the sensors have changed.
787  * If this happens, previously received lists from this method will be stale.
788  *
789  * Available since API level 33.
790  *
791  * \param manager the {@link ASensorManager} instance obtained from
792  *                {@link ASensorManager_getInstanceForPackage}.
793  * \param list    the returned list of dynamic sensors.
794  * \return positive number of returned sensors or negative error code.
795  *         BAD_VALUE: manager is NULL.
796  */
797 ssize_t ASensorManager_getDynamicSensorList(
798         ASensorManager* manager, ASensorList* list) __INTRODUCED_IN(33);
799 
800 /**
801  * Returns the default sensor for the given type, or NULL if no sensor
802  * of that type exists.
803  */
804 ASensor const* ASensorManager_getDefaultSensor(ASensorManager* manager, int type);
805 
806 /**
807  * Returns the default sensor with the given type and wakeUp properties or NULL if no sensor
808  * of this type and wakeUp properties exists.
809  *
810  * Available since API level 21.
811  */
812 ASensor const* ASensorManager_getDefaultSensorEx(ASensorManager* manager, int type, bool wakeUp) __INTRODUCED_IN(21);
813 
814 /**
815  * Creates a new sensor event queue and associate it with a looper.
816  *
817  * "ident" is a identifier for the events that will be returned when
818  * calling ALooper_pollOnce(). The identifier must be >= 0, or
819  * ALOOPER_POLL_CALLBACK if providing a non-NULL callback.
820  */
821 ASensorEventQueue* ASensorManager_createEventQueue(ASensorManager* manager,
822         ALooper* looper, int ident, ALooper_callbackFunc callback, void* data);
823 
824 /**
825  * Destroys the event queue and free all resources associated to it.
826  */
827 int ASensorManager_destroyEventQueue(ASensorManager* manager, ASensorEventQueue* queue);
828 
829 /**
830  * Create direct channel based on shared memory
831  *
832  * Create a direct channel of {@link ASENSOR_DIRECT_CHANNEL_TYPE_SHARED_MEMORY} to be used
833  * for configuring sensor direct report.
834  *
835  * Available since API level 26.
836  *
837  * \param manager the {@link ASensorManager} instance obtained from
838  *                {@link ASensorManager_getInstanceForPackage}.
839  * \param fd      file descriptor representing a shared memory created by
840  *                {@link ASharedMemory_create}
841  * \param size    size to be used, must be less or equal to size of shared memory.
842  *
843  * \return a positive integer as a channel id to be used in
844  *         {@link ASensorManager_destroyDirectChannel} and
845  *         {@link ASensorManager_configureDirectReport}, or value less or equal to 0 for failures.
846  */
847 int ASensorManager_createSharedMemoryDirectChannel(ASensorManager* manager, int fd, size_t size) __INTRODUCED_IN(26);
848 
849 /**
850  * Create direct channel based on AHardwareBuffer
851  *
852  * Create a direct channel of {@link ASENSOR_DIRECT_CHANNEL_TYPE_HARDWARE_BUFFER} type to be used
853  * for configuring sensor direct report.
854  *
855  * Available since API level 26.
856  *
857  * \param manager the {@link ASensorManager} instance obtained from
858  *                {@link ASensorManager_getInstanceForPackage}.
859  * \param buffer  {@link AHardwareBuffer} instance created by {@link AHardwareBuffer_allocate}.
860  * \param size    the intended size to be used, must be less or equal to size of buffer.
861  *
862  * \return a positive integer as a channel id to be used in
863  *         {@link ASensorManager_destroyDirectChannel} and
864  *         {@link ASensorManager_configureDirectReport}, or value less or equal to 0 for failures.
865  */
866 int ASensorManager_createHardwareBufferDirectChannel(
867         ASensorManager* manager, AHardwareBuffer const * buffer, size_t size) __INTRODUCED_IN(26);
868 
869 /**
870  * Destroy a direct channel
871  *
872  * Destroy a direct channel previously created by using one of
873  * ASensorManager_create*DirectChannel() derivative functions.
874  * Note that the buffer used for creating the direct channel does not get destroyed with
875  * ASensorManager_destroyDirectChannel and has to be closed or released separately.
876  *
877  * Available since API level 26.
878  *
879  * \param manager the {@link ASensorManager} instance obtained from
880  *                {@link ASensorManager_getInstanceForPackage}.
881  * \param channelId channel id (a positive integer) returned from
882  *                  {@link ASensorManager_createSharedMemoryDirectChannel} or
883  *                  {@link ASensorManager_createHardwareBufferDirectChannel}.
884  */
885 void ASensorManager_destroyDirectChannel(ASensorManager* manager, int channelId) __INTRODUCED_IN(26);
886 
887 /**
888  * Configure direct report on channel
889  *
890  * Configure sensor direct report on a direct channel: set rate to value other than
891  * {@link ASENSOR_DIRECT_RATE_STOP} so that sensor event can be directly
892  * written into the shared memory region used for creating the buffer. It returns a positive token
893  * which can be used for identify sensor events from different sensors on success. Calling with rate
894  * {@link ASENSOR_DIRECT_RATE_STOP} will stop direct report of the sensor specified in the channel.
895  *
896  * To stop all active sensor direct report configured to a channel, set sensor to NULL and rate to
897  * {@link ASENSOR_DIRECT_RATE_STOP}.
898  *
899  * In order to successfully configure a direct report, the sensor has to support the specified rate
900  * and the channel type, which can be checked by {@link ASensor_getHighestDirectReportRateLevel} and
901  * {@link ASensor_isDirectChannelTypeSupported}, respectively.
902  *
903  * Example:
904  *
905  *     ASensorManager *manager = ...;
906  *     ASensor *sensor = ...;
907  *     int channelId = ...;
908  *
909  *     ASensorManager_configureDirectReport(manager, sensor, channel_id, ASENSOR_DIRECT_RATE_FAST);
910  *
911  * Available since API level 26.
912  *
913  * \param manager   the {@link ASensorManager} instance obtained from
914  *                  {@link ASensorManager_getInstanceForPackage}.
915  * \param sensor    a {@link ASensor} to denote which sensor to be operate. It can be NULL if rate
916  *                  is {@link ASENSOR_DIRECT_RATE_STOP}, denoting stopping of all active sensor
917  *                  direct report.
918  * \param channelId channel id (a positive integer) returned from
919  *                  {@link ASensorManager_createSharedMemoryDirectChannel} or
920  *                  {@link ASensorManager_createHardwareBufferDirectChannel}.
921  * \param rate      one of predefined ASENSOR_DIRECT_RATE_... that is supported by the sensor.
922  * \return positive token for success or negative error code.
923  */
924 int ASensorManager_configureDirectReport(ASensorManager* manager,
925         ASensor const* sensor, int channelId, int rate) __INTRODUCED_IN(26);
926 
927 /*****************************************************************************/
928 
929 /**
930  * Enable the selected sensor with sampling and report parameters
931  *
932  * Enable the selected sensor at a specified sampling period and max batch report latency.
933  * To disable  sensor, use {@link ASensorEventQueue_disableSensor}.
934  *
935  * \param queue {@link ASensorEventQueue} for sensor event to be report to.
936  * \param sensor {@link ASensor} to be enabled.
937  * \param samplingPeriodUs sampling period of sensor in microseconds.
938  * \param maxBatchReportLatencyUs maximum time interval between two batches of sensor events are
939  *                                delievered in microseconds. For sensor streaming, set to 0.
940  * \return 0 on success or a negative error code on failure.
941  */
942 int ASensorEventQueue_registerSensor(ASensorEventQueue* queue, ASensor const* sensor,
943         int32_t samplingPeriodUs, int64_t maxBatchReportLatencyUs);
944 
945 /**
946  * Enable the selected sensor at default sampling rate.
947  *
948  * Start event reports of a sensor to specified sensor event queue at a default rate.
949  *
950  * \param queue {@link ASensorEventQueue} for sensor event to be report to.
951  * \param sensor {@link ASensor} to be enabled.
952  *
953  * \return 0 on success or a negative error code on failure.
954  */
955 int ASensorEventQueue_enableSensor(ASensorEventQueue* queue, ASensor const* sensor);
956 
957 /**
958  * Disable the selected sensor.
959  *
960  * Stop event reports from the sensor to specified sensor event queue.
961  *
962  * \param queue {@link ASensorEventQueue} to be changed
963  * \param sensor {@link ASensor} to be disabled
964  * \return 0 on success or a negative error code on failure.
965  */
966 int ASensorEventQueue_disableSensor(ASensorEventQueue* queue, ASensor const* sensor);
967 
968 /**
969  * Sets the delivery rate of events in microseconds for the given sensor.
970  *
971  * This function has to be called after {@link ASensorEventQueue_enableSensor}.
972  * Note that this is a hint only, generally event will arrive at a higher
973  * rate. It is an error to set a rate inferior to the value returned by
974  * ASensor_getMinDelay().
975  *
976  * \param queue {@link ASensorEventQueue} to which sensor event is delivered.
977  * \param sensor {@link ASensor} of which sampling rate to be updated.
978  * \param usec sensor sampling period (1/sampling rate) in microseconds
979  * \return 0 on sucess or a negative error code on failure.
980  */
981 int ASensorEventQueue_setEventRate(ASensorEventQueue* queue, ASensor const* sensor, int32_t usec);
982 
983 /**
984  * Determine if a sensor event queue has pending event to be processed.
985  *
986  * \param queue {@link ASensorEventQueue} to be queried
987  * \return 1 if the queue has events; 0 if it does not have events;
988  *         or a negative value if there is an error.
989  */
990 int ASensorEventQueue_hasEvents(ASensorEventQueue* queue);
991 
992 /**
993  * Retrieve pending events in sensor event queue
994  *
995  * Retrieve next available events from the queue to a specified event array.
996  *
997  * \param queue {@link ASensorEventQueue} to get events from
998  * \param events pointer to an array of {@link ASensorEvent}.
999  * \param count max number of event that can be filled into array event.
1000  * \return number of events returned on success; negative error code when
1001  *         no events are pending or an error has occurred.
1002  *
1003  * Examples:
1004  *
1005  *     ASensorEvent event;
1006  *     ssize_t numEvent = ASensorEventQueue_getEvents(queue, &event, 1);
1007  *
1008  *     ASensorEvent eventBuffer[8];
1009  *     ssize_t numEvent = ASensorEventQueue_getEvents(queue, eventBuffer, 8);
1010  *
1011  */
1012 ssize_t ASensorEventQueue_getEvents(ASensorEventQueue* queue, ASensorEvent* events, size_t count);
1013 
1014 /**
1015  * Request that {@link ASENSOR_TYPE_ADDITIONAL_INFO} events to be delivered on
1016  * the given {@link ASensorEventQueue}.
1017  *
1018  * Sensor data events are always delivered to the {@link ASensorEventQueue}.
1019  *
1020  * The {@link ASENSOR_TYPE_ADDITIONAL_INFO} events will be returned through
1021  * {@link ASensorEventQueue_getEvents}. The client is responsible for checking
1022  * {@link ASensorEvent#type} to determine the event type prior to handling of
1023  * the event.
1024  *
1025  * The client must be tolerant of any value for
1026  * {@link AAdditionalInfoEvent#type}, as new values may be defined in the future
1027  * and may delivered to the client.
1028  *
1029  * Available since API level 29.
1030  *
1031  * \param queue {@link ASensorEventQueue} to configure
1032  * \param enable true to request {@link ASENSOR_TYPE_ADDITIONAL_INFO} events,
1033  *        false to stop receiving events
1034  * \return 0 on success or a negative error code on failure
1035  */
1036 int ASensorEventQueue_requestAdditionalInfoEvents(ASensorEventQueue* queue, bool enable) __INTRODUCED_IN(29);
1037 
1038 /*****************************************************************************/
1039 
1040 /**
1041  * Returns this sensor's name (non localized)
1042  */
1043 const char* ASensor_getName(ASensor const* sensor);
1044 
1045 /**
1046  * Returns this sensor's vendor's name (non localized)
1047  */
1048 const char* ASensor_getVendor(ASensor const* sensor);
1049 
1050 /**
1051  * Return this sensor's type
1052  */
1053 int ASensor_getType(ASensor const* sensor);
1054 
1055 /**
1056  * Returns this sensors's resolution
1057  */
1058 float ASensor_getResolution(ASensor const* sensor);
1059 
1060 /**
1061  * Returns the minimum delay allowed between events in microseconds.
1062  * A value of zero means that this sensor doesn't report events at a
1063  * constant rate, but rather only when a new data is available.
1064  */
1065 int ASensor_getMinDelay(ASensor const* sensor);
1066 
1067 /**
1068  * Returns the maximum size of batches for this sensor. Batches will often be
1069  * smaller, as the hardware fifo might be used for other sensors.
1070  *
1071  * Available since API level 21.
1072  */
1073 int ASensor_getFifoMaxEventCount(ASensor const* sensor) __INTRODUCED_IN(21);
1074 
1075 /**
1076  * Returns the hardware batch fifo size reserved to this sensor.
1077  *
1078  * Available since API level 21.
1079  */
1080 int ASensor_getFifoReservedEventCount(ASensor const* sensor) __INTRODUCED_IN(21);
1081 
1082 /**
1083  * Returns this sensor's string type.
1084  *
1085  * Available since API level 21.
1086  */
1087 const char* ASensor_getStringType(ASensor const* sensor) __INTRODUCED_IN(21);
1088 
1089 /**
1090  * Returns the reporting mode for this sensor. One of AREPORTING_MODE_* constants.
1091  *
1092  * Available since API level 21.
1093  */
1094 int ASensor_getReportingMode(ASensor const* sensor) __INTRODUCED_IN(21);
1095 
1096 /**
1097  * Returns true if this is a wake up sensor, false otherwise.
1098  *
1099  * Available since API level 21.
1100  */
1101 bool ASensor_isWakeUpSensor(ASensor const* sensor) __INTRODUCED_IN(21);
1102 
1103 /**
1104  * Test if sensor supports a certain type of direct channel.
1105  *
1106  * Available since API level 26.
1107  *
1108  * \param sensor  a {@link ASensor} to denote the sensor to be checked.
1109  * \param channelType  Channel type constant, either
1110  *                     {@link ASENSOR_DIRECT_CHANNEL_TYPE_SHARED_MEMORY}
1111  *                     or {@link ASENSOR_DIRECT_CHANNEL_TYPE_HARDWARE_BUFFER}.
1112  * \returns true if sensor supports the specified direct channel type.
1113  */
1114 bool ASensor_isDirectChannelTypeSupported(ASensor const* sensor, int channelType) __INTRODUCED_IN(26);
1115 
1116 /**
1117  * Get the highest direct rate level that a sensor supports.
1118  *
1119  * Available since API level 26.
1120  *
1121  * \param sensor  a {@link ASensor} to denote the sensor to be checked.
1122  *
1123  * \return a ASENSOR_DIRECT_RATE_... enum denoting the highest rate level supported by the sensor.
1124  *         If return value is {@link ASENSOR_DIRECT_RATE_STOP}, it means the sensor
1125  *         does not support direct report.
1126  */
1127 int ASensor_getHighestDirectReportRateLevel(ASensor const* sensor) __INTRODUCED_IN(26);
1128 
1129 /**
1130  * Returns the sensor's handle.
1131  *
1132  * The handle identifies the sensor within the system and is included in the
1133  * sensor field of {@link ASensorEvent}, including those sent with type
1134  * {@link ASENSOR_TYPE_ADDITIONAL_INFO}.
1135  *
1136  * A sensor's handle is able to be used to map {@link ASENSOR_TYPE_ADDITIONAL_INFO} events to the
1137  * sensor that generated the event.
1138  *
1139  * It is important to note that the value returned by {@link ASensor_getHandle} is not the same as
1140  * the value returned by the Java API <a href="/reference/android/hardware/Sensor#getId()">
1141  * android.hardware.Sensor's getId()</a> and no mapping exists between the values.
1142  *
1143  * Available since API level 29.
1144  */
1145 int ASensor_getHandle(ASensor const* sensor) __INTRODUCED_IN(29);
1146 
1147 #ifdef __cplusplus
1148 };
1149 #endif
1150 
1151 #endif // ANDROID_SENSOR_H
1152 
1153 /** @} */
1154