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 #define LOG_TAG "Sensors"
18
19 #include <sensor/SensorEventQueue.h>
20
21 #include <algorithm>
22 #include <sys/socket.h>
23
24 #include <utils/RefBase.h>
25 #include <utils/Looper.h>
26
27 #include <sensor/Sensor.h>
28 #include <sensor/BitTube.h>
29 #include <sensor/ISensorEventConnection.h>
30
31 #include <android/sensor.h>
32 #include <hardware/sensors-base.h>
33
34 using std::min;
35
36 // ----------------------------------------------------------------------------
37 namespace android {
38 // ----------------------------------------------------------------------------
39
SensorEventQueue(const sp<ISensorEventConnection> & connection)40 SensorEventQueue::SensorEventQueue(const sp<ISensorEventConnection>& connection)
41 : mSensorEventConnection(connection), mRecBuffer(nullptr), mAvailable(0), mConsumed(0),
42 mNumAcksToSend(0) {
43 mRecBuffer = new ASensorEvent[MAX_RECEIVE_BUFFER_EVENT_COUNT];
44 }
45
~SensorEventQueue()46 SensorEventQueue::~SensorEventQueue() {
47 delete [] mRecBuffer;
48 }
49
onFirstRef()50 void SensorEventQueue::onFirstRef()
51 {
52 mSensorChannel = mSensorEventConnection->getSensorChannel();
53 }
54
getFd() const55 int SensorEventQueue::getFd() const
56 {
57 return mSensorChannel->getFd();
58 }
59
60
write(const sp<BitTube> & tube,ASensorEvent const * events,size_t numEvents)61 ssize_t SensorEventQueue::write(const sp<BitTube>& tube,
62 ASensorEvent const* events, size_t numEvents) {
63 return BitTube::sendObjects(tube, events, numEvents);
64 }
65
read(ASensorEvent * events,size_t numEvents)66 ssize_t SensorEventQueue::read(ASensorEvent* events, size_t numEvents) {
67 if (mAvailable == 0) {
68 ssize_t err = BitTube::recvObjects(mSensorChannel,
69 mRecBuffer, MAX_RECEIVE_BUFFER_EVENT_COUNT);
70 if (err < 0) {
71 return err;
72 }
73 mAvailable = static_cast<size_t>(err);
74 mConsumed = 0;
75 }
76 size_t count = min(numEvents, mAvailable);
77 memcpy(events, mRecBuffer + mConsumed, count * sizeof(ASensorEvent));
78 mAvailable -= count;
79 mConsumed += count;
80 return static_cast<ssize_t>(count);
81 }
82
getLooper() const83 sp<Looper> SensorEventQueue::getLooper() const
84 {
85 Mutex::Autolock _l(mLock);
86 if (mLooper == nullptr) {
87 mLooper = new Looper(true);
88 mLooper->addFd(getFd(), getFd(), ALOOPER_EVENT_INPUT, nullptr, nullptr);
89 }
90 return mLooper;
91 }
92
waitForEvent() const93 status_t SensorEventQueue::waitForEvent() const
94 {
95 const int fd = getFd();
96 sp<Looper> looper(getLooper());
97
98 int events;
99 int32_t result;
100 do {
101 result = looper->pollOnce(-1, nullptr, &events, nullptr);
102 if (result == ALOOPER_POLL_ERROR) {
103 ALOGE("SensorEventQueue::waitForEvent error (errno=%d)", errno);
104 result = -EPIPE; // unknown error, so we make up one
105 break;
106 }
107 if (events & ALOOPER_EVENT_HANGUP) {
108 // the other-side has died
109 ALOGE("SensorEventQueue::waitForEvent error HANGUP");
110 result = -EPIPE; // unknown error, so we make up one
111 break;
112 }
113 } while (result != fd);
114
115 return (result == fd) ? status_t(NO_ERROR) : result;
116 }
117
wake() const118 status_t SensorEventQueue::wake() const
119 {
120 sp<Looper> looper(getLooper());
121 looper->wake();
122 return NO_ERROR;
123 }
124
enableSensor(Sensor const * sensor) const125 status_t SensorEventQueue::enableSensor(Sensor const* sensor) const {
126 return enableSensor(sensor, SENSOR_DELAY_NORMAL);
127 }
128
enableSensor(Sensor const * sensor,int32_t samplingPeriodUs) const129 status_t SensorEventQueue::enableSensor(Sensor const* sensor, int32_t samplingPeriodUs) const {
130 return mSensorEventConnection->enableDisable(sensor->getHandle(), true,
131 us2ns(samplingPeriodUs), 0, 0);
132 }
133
disableSensor(Sensor const * sensor) const134 status_t SensorEventQueue::disableSensor(Sensor const* sensor) const {
135 return mSensorEventConnection->enableDisable(sensor->getHandle(), false, 0, 0, 0);
136 }
137
enableSensor(int32_t handle,int32_t samplingPeriodUs,int64_t maxBatchReportLatencyUs,int reservedFlags) const138 status_t SensorEventQueue::enableSensor(int32_t handle, int32_t samplingPeriodUs,
139 int64_t maxBatchReportLatencyUs, int reservedFlags) const {
140 return mSensorEventConnection->enableDisable(handle, true, us2ns(samplingPeriodUs),
141 us2ns(maxBatchReportLatencyUs), reservedFlags);
142 }
143
flush() const144 status_t SensorEventQueue::flush() const {
145 return mSensorEventConnection->flush();
146 }
147
disableSensor(int32_t handle) const148 status_t SensorEventQueue::disableSensor(int32_t handle) const {
149 return mSensorEventConnection->enableDisable(handle, false, 0, 0, false);
150 }
151
setEventRate(Sensor const * sensor,nsecs_t ns) const152 status_t SensorEventQueue::setEventRate(Sensor const* sensor, nsecs_t ns) const {
153 return mSensorEventConnection->setEventRate(sensor->getHandle(), ns);
154 }
155
injectSensorEvent(const ASensorEvent & event)156 status_t SensorEventQueue::injectSensorEvent(const ASensorEvent& event) {
157 do {
158 // Blocking call.
159 ssize_t size = ::send(mSensorChannel->getFd(), &event, sizeof(event), MSG_NOSIGNAL);
160 if (size >= 0) {
161 return NO_ERROR;
162 } else if (size < 0 && errno == EAGAIN) {
163 // If send is returning a "Try again" error, sleep for 100ms and try again. In all
164 // other cases log a failure and exit.
165 usleep(100000);
166 } else {
167 ALOGE("injectSensorEvent failure %s %zd", strerror(errno), size);
168 return INVALID_OPERATION;
169 }
170 } while (true);
171 }
172
sendAck(const ASensorEvent * events,int count)173 void SensorEventQueue::sendAck(const ASensorEvent* events, int count) {
174 for (int i = 0; i < count; ++i) {
175 if (events[i].flags & WAKE_UP_SENSOR_EVENT_NEEDS_ACK) {
176 ++mNumAcksToSend;
177 }
178 }
179 // Send mNumAcksToSend to acknowledge for the wake up sensor events received.
180 if (mNumAcksToSend > 0) {
181 ssize_t size = ::send(mSensorChannel->getFd(), &mNumAcksToSend, sizeof(mNumAcksToSend),
182 MSG_DONTWAIT | MSG_NOSIGNAL);
183 if (size < 0) {
184 ALOGE("sendAck failure %zd %d", size, mNumAcksToSend);
185 } else {
186 mNumAcksToSend = 0;
187 }
188 }
189 return;
190 }
191
filterEvents(ASensorEvent * events,size_t count) const192 ssize_t SensorEventQueue::filterEvents(ASensorEvent* events, size_t count) const {
193 // Check if this Sensor Event Queue is registered to receive each type of event. If it is not,
194 // then do not copy the event into the final buffer. Minimize the number of copy operations by
195 // finding consecutive sequences of events that the Sensor Event Queue should receive and only
196 // copying the events once an unregistered event type is reached.
197 bool intervalStartLocSet = false;
198 size_t intervalStartLoc = 0;
199 size_t eventsInInterval = 0;
200 ssize_t eventsCopied = 0;
201
202 for (size_t i = 0; i < count; i++) {
203 bool includeEvent =
204 (events[i].type != SENSOR_TYPE_ADDITIONAL_INFO || requestAdditionalInfo);
205
206 if (includeEvent) {
207 // Do not copy events yet since there may be more consecutive events that should be
208 // copied together. Track the start location and number of events in the current
209 // sequence.
210 if (!intervalStartLocSet) {
211 intervalStartLoc = i;
212 intervalStartLocSet = true;
213 eventsInInterval = 0;
214 }
215 eventsInInterval++;
216 }
217
218 // Shift the events from the already processed interval once an event that should not be
219 // included is reached or if this is the final event to be processed.
220 if (!includeEvent || (i + 1 == count)) {
221 // Only shift the events if the interval did not start with the first event. If the
222 // interval started with the first event, the events are already in their correct
223 // location.
224 if (intervalStartLoc > 0) {
225 memmove(&events[eventsCopied], &events[intervalStartLoc],
226 eventsInInterval * sizeof(ASensorEvent));
227 }
228 eventsCopied += eventsInInterval;
229
230 // Reset the interval information
231 eventsInInterval = 0;
232 intervalStartLocSet = false;
233 }
234 }
235 return eventsCopied;
236 }
237
238 // ----------------------------------------------------------------------------
239 }; // namespace android
240
241