service/src/com/android/car/AidlVehicleStub.java

/*
 * Copyright (C) 2021 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.
 */

package com.android.car;

import android.annotation.Nullable;
import android.car.builtin.os.ServiceManagerHelper;
import android.car.builtin.util.Slogf;
import android.hardware.automotive.vehicle.IVehicle;
import android.hardware.automotive.vehicle.SubscribeOptions;
import android.os.RemoteException;
import android.os.ServiceSpecificException;

import com.android.car.hal.HalClientCallback;
import com.android.car.hal.HalPropConfig;
import com.android.car.hal.HalPropValue;
import com.android.car.hal.HalPropValueBuilder;
import com.android.internal.annotations.VisibleForTesting;

final class AidlVehicleStub extends VehicleStub {

    private static final String AIDL_VHAL_SERVICE =
            "android.hardware.automotive.vehicle.IVehicle/default";

    private final IVehicle mAidlVehicle;
    private final HalPropValueBuilder mPropValueBuilder;

    AidlVehicleStub() {
        this(getAidlVehicle());
    }

    @VisibleForTesting
    AidlVehicleStub(IVehicle aidlVehicle) {
        mAidlVehicle = aidlVehicle;
        mPropValueBuilder = new HalPropValueBuilder(/*isAidl=*/true);
    }


    /**
     * Gets a HalPropValueBuilder that could be used to build a HalPropValue.
     *
     * @return a builder to build HalPropValue.
     */
    @Override
    public HalPropValueBuilder getHalPropValueBuilder() {
        return mPropValueBuilder;
    }

    /**
     * Returns whether this vehicle stub is connecting to a valid vehicle HAL.
     *
     * @return Whether this vehicle stub is connecting to a valid vehicle HAL.
     */
    @Override
    public boolean isValid() {
        return mAidlVehicle != null;
    }

    /**
     * Gets the interface descriptor for the connecting vehicle HAL.
     *
     * @return the interface descriptor.
     * @throws IllegalStateException If unable to get the descriptor.
     */
    @Override
    public String getInterfaceDescriptor() throws IllegalStateException {
        try {
            return mAidlVehicle.asBinder().getInterfaceDescriptor();
        } catch (RemoteException e) {
            throw new IllegalStateException("Unable to get Vehicle HAL interface descriptor", e);
        }
    }

    /**
     * Register a death recipient that would be called when vehicle HAL died.
     *
     * @param recipient A death recipient.
     * @throws IllegalStateException If unable to register the death recipient.
     */
    @Override
    public void linkToDeath(IVehicleDeathRecipient recipient) throws IllegalStateException {
        try {
            mAidlVehicle.asBinder().linkToDeath(recipient, /*flag=*/ 0);
        } catch (RemoteException e) {
            throw new IllegalStateException("Failed to linkToDeath Vehicle HAL");
        }
    }

    /**
     * Unlink a previously linked death recipient.
     *
     * @param recipient A previously linked death recipient.
     */
    @Override
    public void unlinkToDeath(IVehicleDeathRecipient recipient) {
        mAidlVehicle.asBinder().unlinkToDeath(recipient, /*flag=*/ 0);
    }

    /**
     * Get all property configs.
     *
     * @return All the property configs.
     * @throws RemoteException if the remote operation fails.
     * @throws ServiceSpecificException if VHAL returns service specific error.
     */
    @Override
    public HalPropConfig[] getAllPropConfigs()
            throws RemoteException, ServiceSpecificException {
        // TODO(b/205774940): Call AIDL APIs.
        return null;
    }

    /**
     * Subscribe to a property.
     *
     * @param callback The VehicleStubCallback that would be called for subscribe events.
     * @param options The list of subscribe options.
     * @throws RemoteException if the remote operation fails.
     * @throws ServiceSpecificException if VHAL returns service specific error.
     */
    @Override
    public void subscribe(VehicleStubCallback callback, SubscribeOptions[] options)
            throws RemoteException, ServiceSpecificException {
        // TODO(b/205774940): Call AIDL APIs.
        return;
    }

    /**
     * Unsubscribe to a property.
     *
     * @param callback The previously subscribed callback to unsubscribe.
     * @param prop The ID for the property to unsubscribe.
     * @throws RemoteException if the remote operation fails.
     * @throws ServiceSpecificException if VHAL returns service specific error.
     */
    @Override
    public void unsubscribe(VehicleStubCallback callback, int prop)
            throws RemoteException, ServiceSpecificException {
        // TODO(b/205774940): Call AIDL APIs.
        return;
    }

    /**
     * Get a new {@code VehicleStubCallback} that could be used to subscribe/unsubscribe.
     *
     * @param callback A callback that could be used to receive events.
     * @return a {@code VehicleStubCallback} that could be passed to subscribe/unsubscribe.
     */
    @Override
    public VehicleStubCallback newCallback(HalClientCallback callback) {
        // TODO(b/205774940): Return AIDL callback.
        return null;
    }

    /**
     * Get a property.
     *
     * @param requestedPropValue The property to get.
     * @return The vehicle property value.
     * @throws RemoteException if the remote operation fails.
     * @throws ServiceSpecificException if VHAL returns service specific error.
     */
    @Override
    @Nullable
    public HalPropValue get(HalPropValue requestedPropValue)
            throws RemoteException, ServiceSpecificException {
        // TODO(b/205774940): Call AIDL APIs.
        return null;
    }

    /**
     * Set a property.
     *
     * @param propValue The property to set.
     * @throws RemoteException if the remote operation fails.
     * @throws ServiceSpecificException if VHAL returns service specific error.
     */
    @Override
    public void set(HalPropValue propValue) throws RemoteException, ServiceSpecificException {
        // TODO(b/205774940): Call AIDL APIs.
        return;
    }

    @Nullable
    private static IVehicle getAidlVehicle() {
        try {
            return IVehicle.Stub.asInterface(
                    ServiceManagerHelper.waitForDeclaredService(AIDL_VHAL_SERVICE));
        } catch (RuntimeException e) {
            Slogf.w(CarLog.TAG_SERVICE, "Failed to get \"" + AIDL_VHAL_SERVICE + "\" service", e);
        }
        return null;
    }
}