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 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 46 SensorEventQueue::~SensorEventQueue() { 47 delete [] mRecBuffer; 48 } 49 50 void SensorEventQueue::onFirstRef() 51 { 52 mSensorChannel = mSensorEventConnection->getSensorChannel(); 53 } 54 55 int SensorEventQueue::getFd() const 56 { 57 return mSensorChannel->getFd(); 58 } 59 60 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 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 83 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 93 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 } 117 118 status_t SensorEventQueue::wake() const 119 { 120 sp<Looper> looper(getLooper()); 121 looper->wake(); 122 return NO_ERROR; 123 } 124 125 status_t SensorEventQueue::enableSensor(Sensor const* sensor) const { 126 return enableSensor(sensor, SENSOR_DELAY_NORMAL); 127 } 128 129 status_t SensorEventQueue::enableSensor(Sensor const* sensor, int32_t samplingPeriodUs) const { 130 return mSensorEventConnection->enableDisable(sensor->getHandle(), true, 131 us2ns(samplingPeriodUs), 0, 0); 132 } 133 134 status_t SensorEventQueue::disableSensor(Sensor const* sensor) const { 135 return mSensorEventConnection->enableDisable(sensor->getHandle(), false, 0, 0, 0); 136 } 137 138 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 } 143 144 status_t SensorEventQueue::flush() const { 145 return mSensorEventConnection->flush(); 146 } 147 148 status_t SensorEventQueue::disableSensor(int32_t handle) const { 149 return mSensorEventConnection->enableDisable(handle, false, 0, 0, false); 150 } 151 152 status_t SensorEventQueue::setEventRate(Sensor const* sensor, nsecs_t ns) const { 153 return mSensorEventConnection->setEventRate(sensor->getHandle(), ns); 154 } 155 156 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 } 172 173 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 } 191 192 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
