[CrashRecovery] Adding helper methods

/*

 * Copyright (C) 2024 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.server.crashrecovery;

import android.annotation.AnyThread;

import android.annotation.NonNull;

import android.annotation.Nullable;

import android.content.Context;

import android.content.pm.PackageInfo;

import android.content.pm.PackageManager;

import android.content.pm.VersionedPackage;

import android.net.ConnectivityModuleConnector;

import android.text.TextUtils;

import android.util.Slog;

import com.android.server.PackageWatchdog;

import com.android.server.pm.ApexManager;

import java.util.Collections;

import java.util.List;

/**

 * Provides helper methods for the CrashRecovery APEX

 *

 * @hide

 */

public final class CrashRecoveryHelper {

    private static final String TAG = "CrashRecoveryHelper";

    private final ApexManager mApexManager;

    private final Context mContext;

    private final ConnectivityModuleConnector mConnectivityModuleConnector;

    /** @hide */

    public CrashRecoveryHelper(@NonNull Context context) {

        mContext = context;

        mApexManager = ApexManager.getInstance();

        mConnectivityModuleConnector = ConnectivityModuleConnector.getInstance();

    }

    /**

     * Returns true if the package name is the name of a module.

     * If the package is an APK inside an APEX then it will use the parent's APEX package name

     * do determine if it is a module or not.

     * @hide

     */

    @AnyThread

    public boolean isModule(@NonNull String packageName) {

        String apexPackageName =

                mApexManager.getActiveApexPackageNameContainingPackage(packageName);

        if (apexPackageName != null) {

            packageName = apexPackageName;

        }

        PackageManager pm = mContext.getPackageManager();

        try {

            return pm.getModuleInfo(packageName, 0) != null;

        } catch (PackageManager.NameNotFoundException ignore) {

            return false;

        }

    }

    /**

     * Register health listeners for explicit package failures.

     * Currently only registering for Connectivity Module health.

     * @hide

     */

    public void registerConnectivityModuleHealthListener(@NonNull int failureReason) {

        // register listener for ConnectivityModule

        mConnectivityModuleConnector.registerHealthListener(

                packageName -> {

                final VersionedPackage pkg = getVersionedPackage(packageName);

                if (pkg == null) {

                    Slog.wtf(TAG, "NetworkStack failed but could not find its package");

                    return;

                }

                final List<VersionedPackage> pkgList = Collections.singletonList(pkg);

                PackageWatchdog.getInstance(mContext).onPackageFailure(pkgList, failureReason);

            });

    }

    @Nullable

    private VersionedPackage getVersionedPackage(String packageName) {

        final PackageManager pm = mContext.getPackageManager();

        if (pm == null || TextUtils.isEmpty(packageName)) {

            return null;

        }

        try {

            final long versionCode = getPackageInfo(packageName).getLongVersionCode();

            return new VersionedPackage(packageName, versionCode);

        } catch (PackageManager.NameNotFoundException e) {

            return null;

        }

    }

    /**

     * Gets PackageInfo for the given package. Matches any user and apex.

     *

     * @throws PackageManager.NameNotFoundException if no such package is installed.

     */

    private PackageInfo getPackageInfo(String packageName)

            throws PackageManager.NameNotFoundException {

        PackageManager pm = mContext.getPackageManager();

        try {

            // The MATCH_ANY_USER flag doesn't mix well with the MATCH_APEX

            // flag, so make two separate attempts to get the package info.

            // We don't need both flags at the same time because we assume

            // apex files are always installed for all users.

            return pm.getPackageInfo(packageName, PackageManager.MATCH_ANY_USER);

        } catch (PackageManager.NameNotFoundException e) {

            return pm.getPackageInfo(packageName, PackageManager.MATCH_APEX);

        }

    }

}

ancr@google.com

harshitmahajan@google.com

robertogil@google.com