bool SensorService::threadLoop()
{
    ALOGD("nuSensorService thread starting...");

    const size_t numEventMax = 16;
    const size_t minBufferSize = numEventMax + numEventMax * mVirtualSensorList.size();
    sensors_event_t buffer[minBufferSize];
    sensors_event_t scratch[minBufferSize];
    SensorDevice& device(SensorDevice::getInstance());
    const size_t vcount = mVirtualSensorList.size();

    ssize_t count;
    do {
        count = device.poll(buffer, numEventMax);
        if (count<0) {
            ALOGE("sensor poll failed (%s)", strerror(-count));
            break;
        }
/* fix err PTR when count=0  -- by liaoxl.lenovo 1.22.2013 start */
#if 0
        recordLastValue(buffer, count);

        // handle virtual sensors
        if (count && vcount) {
            sensors_event_t const * const event = buffer;
            const DefaultKeyedVector<int, SensorInterface*> virtualSensors(
                    getActiveVirtualSensors());
            const size_t activeVirtualSensorCount = virtualSensors.size();
            if (activeVirtualSensorCount) {
                size_t k = 0;
                SensorFusion& fusion(SensorFusion::getInstance());
                if (fusion.isEnabled()) {
                    for (size_t i=0 ; i<size_t(count) ; i++) {
                        fusion.process(event[i]);
                    }
                }
                for (size_t i=0 ; i<size_t(count) && k<minBufferSize ; i++) {
                    for (size_t j=0 ; j<activeVirtualSensorCount ; j++) {
                        if (count + k >= minBufferSize) {
                            ALOGE("buffer too small to hold all events: "
                                    "count=%u, k=%u, size=%u",
                                    count, k, minBufferSize);
                            break;
                        }
                        sensors_event_t out;
                        SensorInterface* si = virtualSensors.valueAt(j);
                        if (si->process(&out, event[i])) {
                            buffer[count + k] = out;
                            k++;
                        }
                    }
                }
                if (k) {
                    // record the last synthesized values
                    recordLastValue(&buffer[count], k);
                    count += k;
                    // sort the buffer by time-stamps
                    sortEventBuffer(buffer, count);
                }
            }
        }

        // send our events to clients...
        const SortedVector< wp<SensorEventConnection> > activeConnections(
                getActiveConnections());
        size_t numConnections = activeConnections.size();
        for (size_t i=0 ; i<numConnections ; i++) {
            sp<SensorEventConnection> connection(
                    activeConnections[i].promote());
            if (connection != 0) {
                connection->sendEvents(buffer, count, scratch);
            }
        }
    } while (count >= 0 || Thread::exitPending());

#else
        else if(count == 0)
bool SensorService::threadLoop()
{
    LOGD("nuSensorService thread starting...");

    const size_t numEventMax = 16 * (1 + mVirtualSensorList.size());
    sensors_event_t buffer[numEventMax];
    sensors_event_t scratch[numEventMax];
    SensorDevice& device(SensorDevice::getInstance());
    const size_t vcount = mVirtualSensorList.size();

    ssize_t count;
    do {
        count = device.poll(buffer, numEventMax);
        if (count<0) {
            LOGE("sensor poll failed (%s)", strerror(-count));
            break;
        }

        recordLastValue(buffer, count);

        // handle virtual sensors
        if (count && vcount) {
            sensors_event_t const * const event = buffer;
            const DefaultKeyedVector<int, SensorInterface*> virtualSensors(
                    getActiveVirtualSensors());
            const size_t activeVirtualSensorCount = virtualSensors.size();
            if (activeVirtualSensorCount) {
                size_t k = 0;
                SensorFusion& fusion(SensorFusion::getInstance());
                if (fusion.isEnabled()) {
                    for (size_t i=0 ; i<size_t(count) ; i++) {
                        fusion.process(event[i]);
                    }
                }
                for (size_t i=0 ; i<size_t(count) ; i++) {
                    for (size_t j=0 ; j<activeVirtualSensorCount ; j++) {
                        sensors_event_t out;
                        if (virtualSensors.valueAt(j)->process(&out, event[i])) {
                            buffer[count + k] = out;
                            k++;
                        }
                    }
                }
                if (k) {
                    // record the last synthesized values
                    recordLastValue(&buffer[count], k);
                    count += k;
                    // sort the buffer by time-stamps
                    sortEventBuffer(buffer, count);
                }
            }
        }

        // send our events to clients...
        const SortedVector< wp<SensorEventConnection> > activeConnections(
                getActiveConnections());
        size_t numConnections = activeConnections.size();
        for (size_t i=0 ; i<numConnections ; i++) {
            sp<SensorEventConnection> connection(
                    activeConnections[i].promote());
            if (connection != 0) {
                connection->sendEvents(buffer, count, scratch);
            }
        }
    } while (count >= 0 || Thread::exitPending());

    LOGW("Exiting SensorService::threadLoop => aborting...");
    abort();
    return false;
}