1 /**
2  * Copyright (C) 2022 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.server.broadcastradio;
18 
19 import android.app.ActivityManager;
20 import android.os.Binder;
21 import android.os.UserHandle;
22 
23 /**
24  * Controller to handle users in {@link com.android.server.broadcastradio.BroadcastRadioService}
25  */
26 public final class RadioServiceUserController {
27 
RadioServiceUserController()28     private RadioServiceUserController() {
29         throw new UnsupportedOperationException(
30                 "RadioServiceUserController class is noninstantiable");
31     }
32 
33     /**
34      * Check if the user calling the method in Broadcast Radio Service is the current user or the
35      * system user.
36      *
37      * @return {@code true} if the user calling this method is the current user of system user,
38      * {@code false} otherwise.
39      */
isCurrentOrSystemUser()40     public static boolean isCurrentOrSystemUser() {
41         int callingUser = Binder.getCallingUserHandle().getIdentifier();
42         return callingUser == getCurrentUser() || callingUser == UserHandle.USER_SYSTEM;
43     }
44 
45     /**
46      * Get current foreground user for Broadcast Radio Service
47      *
48      * @return foreground user id.
49      */
getCurrentUser()50     public static int getCurrentUser() {
51         int userId = UserHandle.USER_NULL;
52         final long identity = Binder.clearCallingIdentity();
53         try {
54             userId = ActivityManager.getCurrentUser();
55         } catch (RuntimeException e) {
56             // Activity manager not running, nothing we can do assume user 0.
57         } finally {
58             Binder.restoreCallingIdentity(identity);
59         }
60         return userId;
61     }
62 }
63