/*
* 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.
*/
#define LOG_TAG "Sensors"
#include <sensor/SensorEventQueue.h>
#include <algorithm>
#include <sys/socket.h>
#include <utils/RefBase.h>
#include <utils/Looper.h>
#include <sensor/Sensor.h>
#include <sensor/BitTube.h>
#include <sensor/ISensorEventConnection.h>
#include <android/sensor.h>
#include <hardware/sensors-base.h>
using std::min;
// ----------------------------------------------------------------------------
namespace android {
// ----------------------------------------------------------------------------
SensorEventQueue::SensorEventQueue(const sp<ISensorEventConnection>& connection)
: mSensorEventConnection(connection), mRecBuffer(nullptr), mAvailable(0), mConsumed(0),
mNumAcksToSend(0) {
mRecBuffer = new ASensorEvent[MAX_RECEIVE_BUFFER_EVENT_COUNT];
}
SensorEventQueue::~SensorEventQueue() {
delete [] mRecBuffer;
}
void SensorEventQueue::onFirstRef()
{
mSensorChannel = mSensorEventConnection->getSensorChannel();
}
int SensorEventQueue::getFd() const
{
return mSensorChannel->getFd();
}
ssize_t SensorEventQueue::write(const sp<BitTube>& tube,
ASensorEvent const* events, size_t numEvents) {
return BitTube::sendObjects(tube, events, numEvents);
}
ssize_t SensorEventQueue::read(ASensorEvent* events, size_t numEvents) {
if (mAvailable == 0) {
ssize_t err = BitTube::recvObjects(mSensorChannel,
mRecBuffer, MAX_RECEIVE_BUFFER_EVENT_COUNT);
if (err < 0) {
return err;
}
mAvailable = static_cast<size_t>(err);
mConsumed = 0;
}
size_t count = min(numEvents, mAvailable);
memcpy(events, mRecBuffer + mConsumed, count * sizeof(ASensorEvent));
mAvailable -= count;
mConsumed += count;
return static_cast<ssize_t>(count);
}
sp<Looper> SensorEventQueue::getLooper() const
{
Mutex::Autolock _l(mLock);
if (mLooper == nullptr) {
mLooper = new Looper(true);
mLooper->addFd(getFd(), getFd(), ALOOPER_EVENT_INPUT, nullptr, nullptr);
}
return mLooper;
}
status_t SensorEventQueue::waitForEvent() const
{
const int fd = getFd();
sp<Looper> looper(getLooper());
int events;
int32_t result;
do {
result = looper->pollOnce(-1, nullptr, &events, nullptr);
if (result == ALOOPER_POLL_ERROR) {
ALOGE("SensorEventQueue::waitForEvent error (errno=%d)", errno);
result = -EPIPE; // unknown error, so we make up one
break;
}
if (events & ALOOPER_EVENT_HANGUP) {
// the other-side has died
ALOGE("SensorEventQueue::waitForEvent error HANGUP");
result = -EPIPE; // unknown error, so we make up one
break;
}
} while (result != fd);
return (result == fd) ? status_t(NO_ERROR) : result;
}
status_t SensorEventQueue::wake() const
{
sp<Looper> looper(getLooper());
looper->wake();
return NO_ERROR;
}
status_t SensorEventQueue::enableSensor(Sensor const* sensor) const {
return enableSensor(sensor, SENSOR_DELAY_NORMAL);
}
status_t SensorEventQueue::enableSensor(Sensor const* sensor, int32_t samplingPeriodUs) const {
return mSensorEventConnection->enableDisable(sensor->getHandle(), true,
us2ns(samplingPeriodUs), 0, 0);
}
status_t SensorEventQueue::disableSensor(Sensor const* sensor) const {
return mSensorEventConnection->enableDisable(sensor->getHandle(), false, 0, 0, 0);
}
status_t SensorEventQueue::enableSensor(int32_t handle, int32_t samplingPeriodUs,
int64_t maxBatchReportLatencyUs, int reservedFlags) const {
return mSensorEventConnection->enableDisable(handle, true, us2ns(samplingPeriodUs),
us2ns(maxBatchReportLatencyUs), reservedFlags);
}
status_t SensorEventQueue::flush() const {
return mSensorEventConnection->flush();
}
status_t SensorEventQueue::disableSensor(int32_t handle) const {
return mSensorEventConnection->enableDisable(handle, false, 0, 0, false);
}
status_t SensorEventQueue::setEventRate(Sensor const* sensor, nsecs_t ns) const {
return mSensorEventConnection->setEventRate(sensor->getHandle(), ns);
}
status_t SensorEventQueue::injectSensorEvent(const ASensorEvent& event) {
do {
// Blocking call.
ssize_t size = ::send(mSensorChannel->getFd(), &event, sizeof(event), MSG_NOSIGNAL);
if (size >= 0) {
return NO_ERROR;
} else if (size < 0 && errno == EAGAIN) {
// If send is returning a "Try again" error, sleep for 100ms and try again. In all
// other cases log a failure and exit.
usleep(100000);
} else {
ALOGE("injectSensorEvent failure %s %zd", strerror(errno), size);
return INVALID_OPERATION;
}
} while (true);
}
void SensorEventQueue::sendAck(const ASensorEvent* events, int count) {
for (int i = 0; i < count; ++i) {
if (events[i].flags & WAKE_UP_SENSOR_EVENT_NEEDS_ACK) {
++mNumAcksToSend;
}
}
// Send mNumAcksToSend to acknowledge for the wake up sensor events received.
if (mNumAcksToSend > 0) {
ssize_t size = ::send(mSensorChannel->getFd(), &mNumAcksToSend, sizeof(mNumAcksToSend),
MSG_DONTWAIT | MSG_NOSIGNAL);
if (size < 0) {
ALOGE("sendAck failure %zd %d", size, mNumAcksToSend);
} else {
mNumAcksToSend = 0;
}
}
return;
}
ssize_t SensorEventQueue::filterEvents(ASensorEvent* events, size_t count) const {
// Check if this Sensor Event Queue is registered to receive each type of event. If it is not,
// then do not copy the event into the final buffer. Minimize the number of copy operations by
// finding consecutive sequences of events that the Sensor Event Queue should receive and only
// copying the events once an unregistered event type is reached.
bool intervalStartLocSet = false;
size_t intervalStartLoc = 0;
size_t eventsInInterval = 0;
ssize_t eventsCopied = 0;
for (size_t i = 0; i < count; i++) {
bool includeEvent =
(events[i].type != SENSOR_TYPE_ADDITIONAL_INFO || requestAdditionalInfo);
if (includeEvent) {
// Do not copy events yet since there may be more consecutive events that should be
// copied together. Track the start location and number of events in the current
// sequence.
if (!intervalStartLocSet) {
intervalStartLoc = i;
intervalStartLocSet = true;
eventsInInterval = 0;
}
eventsInInterval++;
}
// Shift the events from the already processed interval once an event that should not be
// included is reached or if this is the final event to be processed.
if (!includeEvent || (i + 1 == count)) {
// Only shift the events if the interval did not start with the first event. If the
// interval started with the first event, the events are already in their correct
// location.
if (intervalStartLoc > 0) {
memmove(&events[eventsCopied], &events[intervalStartLoc],
eventsInInterval * sizeof(ASensorEvent));
}
eventsCopied += eventsInInterval;
// Reset the interval information
eventsInInterval = 0;
intervalStartLocSet = false;
}
}
return eventsCopied;
}
// ----------------------------------------------------------------------------
}; // namespace android