Merge "Look for prediction model in vendor partition" into udc-dev

constexpr char OUTPUT_PHI[] = "phi";

constexpr char OUTPUT_PRESSURE[] = "pressure";

// Ideally, we would just use std::filesystem::exists here, but it requires libc++fs, which causes

// build issues in other parts of the system.

#if defined(__ANDROID__)

bool fileExists(const char* filename) {

    struct stat buffer;

    return stat(filename, &buffer) == 0;

}

#endif

std::string getModelPath() {

#if defined(__ANDROID__)

    static const char* oemModel = "/vendor/etc/motion_predictor_model.fb";

    if (fileExists(oemModel)) {

        return oemModel;

    }

    return "/system/etc/motion_predictor_model.fb";

#else

    return base::GetExecutableDirectory() + "/motion_predictor_model.fb";

std::unique_ptr<TfLiteMotionPredictorModel> TfLiteMotionPredictorModel::create() {

    const std::string modelPath = getModelPath();

    const int fd = open(modelPath.c_str(), O_RDONLY);

    android::base::unique_fd fd(open(modelPath.c_str(), O_RDONLY));

    if (fd == -1) {

        PLOG(FATAL) << "Could not read model from " << modelPath;

    }

    if (!modelBuffer) {

        PLOG(FATAL) << "Failed to mmap model";

    }

    if (close(fd) == -1) {

        PLOG(FATAL) << "Failed to close model fd";

    }

    return std::unique_ptr<TfLiteMotionPredictorModel>(

            new TfLiteMotionPredictorModel(std::move(modelBuffer)));