Merge "Add ApexContext API including methods to get paths for data directories."

package android.content {

  public class ApexContext {

    method @NonNull public static android.content.ApexContext getApexContext(@NonNull String);

    method @NonNull public java.io.File getCredentialProtectedDataDirForUser(@NonNull android.os.UserHandle);

    method @NonNull public java.io.File getDeviceProtectedDataDir();

    method @NonNull public java.io.File getDeviceProtectedDataDirForUser(@NonNull android.os.UserHandle);

  }

  public abstract class BroadcastReceiver {

    method @NonNull public final android.os.UserHandle getSendingUser();

  }

/*

 * Copyright (C) 2020 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 android.content;

import android.annotation.NonNull;

import android.annotation.SystemApi;

import android.os.Environment;

import android.os.UserHandle;

import java.io.File;

import java.util.Objects;

/**

 * Provides information about the environment for a particular APEX.

 *

 * @hide

 */

@SystemApi

public class ApexContext {

    private static final String APEX_DATA = "apexdata";

    /**

     * Returns an ApexContext instance for the APEX with the provided {@code apexModuleName}.

     *

     * <p>To preserve the safety and integrity of APEX modules, you must only obtain the ApexContext

     * for your specific APEX, and you <em>must never</em> attempt to obtain an ApexContext for

     * another APEX.  Any coordination between APEXs must be performed through well-defined

     * interfaces; attempting to directly read or write raw files belonging to another APEX will

     * violate the hermetic storage requirements placed upon each module.

     */

    @NonNull

    public static ApexContext getApexContext(@NonNull String apexModuleName) {

        Objects.requireNonNull(apexModuleName, "apexModuleName cannot be null");

        //TODO(b/141148175): Check that apexModuleName is an actual APEX name

        return new ApexContext(apexModuleName);

    }

    private final String mApexModuleName;

    private ApexContext(String apexModuleName) {

        mApexModuleName = apexModuleName;

    }

    /**

     * Returns the data directory for the APEX in device-encrypted, non-user-specific storage.

     *

     * <p>This directory is automatically created by the system for installed APEXes, and its

     * contents will be rolled back if the APEX is rolled back.

     */

    @NonNull

    public File getDeviceProtectedDataDir() {

        return Environment.buildPath(

                Environment.getDataMiscDirectory(), APEX_DATA, mApexModuleName);

    }

    /**

     * Returns the data directory for the APEX in device-encrypted, user-specific storage for the

     * specified {@code user}.

     *

     * <p>This directory is automatically created by the system for each user and for each installed

     * APEX, and its contents will be rolled back if the APEX is rolled back.

     */

    @NonNull

    public File getDeviceProtectedDataDirForUser(@NonNull UserHandle user) {

        return Environment.buildPath(

                Environment.getDataMiscDeDirectory(user.getIdentifier()), APEX_DATA,

                mApexModuleName);

    }

    /**

     * Returns the data directory for the APEX in credential-encrypted, user-specific storage for

     * the specified {@code user}.

     *

     * <p>This directory is automatically created by the system for each user and for each installed

     * APEX, and its contents will be rolled back if the APEX is rolled back.

     */

    @NonNull

    public File getCredentialProtectedDataDirForUser(@NonNull UserHandle user) {

        return Environment.buildPath(

                Environment.getDataMiscCeDirectory(user.getIdentifier()), APEX_DATA,

                mApexModuleName);

    }

}

/*

 * Copyright (C) 2020 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 android.content;

import static org.junit.Assert.assertEquals;

import android.os.UserHandle;

import androidx.test.filters.SmallTest;

import androidx.test.runner.AndroidJUnit4;

import org.junit.Test;

import org.junit.runner.RunWith;

@SmallTest

@RunWith(AndroidJUnit4.class)

public class ApexContextTest {

    @Test

    public void dataDirectoryPathsAreAsExpected() {

        ApexContext apexContext = ApexContext.getApexContext("my.apex");

        assertEquals("/data/misc/apexdata/my.apex",

                apexContext.getDeviceProtectedDataDir().getAbsolutePath());

        assertEquals("/data/misc_de/5/apexdata/my.apex",

                apexContext.getDeviceProtectedDataDirForUser(UserHandle.of(5)).getAbsolutePath());

        assertEquals("/data/misc_ce/16/apexdata/my.apex",

                apexContext.getCredentialProtectedDataDirForUser(

                        UserHandle.of(16)).getAbsolutePath());

    }

}