split libsensor our of libgui 

Test: compile & run
Bug: treble cleanup
Change-Id: I5b2c2a14f7d3b364d25695cf0901c5b08cfb0fc9
diff --git a/libs/sensor/SensorEventQueue.cpp b/libs/sensor/SensorEventQueue.cpp
new file mode 100644
index 0000000..8ba3ebe
--- /dev/null
+++ b/libs/sensor/SensorEventQueue.cpp
@@ -0,0 +1,193 @@
+/*
+ * 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>
+
+using std::min;
+
+// ----------------------------------------------------------------------------
+namespace android {
+// ----------------------------------------------------------------------------
+
+SensorEventQueue::SensorEventQueue(const sp<ISensorEventConnection>& connection)
+    : mSensorEventConnection(connection), mRecBuffer(NULL), 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 == 0) {
+        mLooper = new Looper(true);
+        mLooper->addFd(getFd(), getFd(), ALOOPER_EVENT_INPUT, NULL, NULL);
+    }
+    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, NULL, &events, NULL);
+        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,
+                                        int 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;
+}
+
+// ----------------------------------------------------------------------------
+}; // namespace android
+