1 /*
2  * Copyright (C) 2023 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  *      https://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.packageinstaller.common;
18 
19 import android.content.BroadcastReceiver;
20 import android.content.Context;
21 import android.content.Intent;
22 import android.os.SystemClock;
23 import android.util.Log;
24 
25 import androidx.annotation.NonNull;
26 
27 import java.io.File;
28 import java.io.IOException;
29 
30 /**
31  * Manages files of the package installer and resets state during boot.
32  */
33 public class TemporaryFileManager extends BroadcastReceiver {
34     private static final String LOG_TAG = TemporaryFileManager.class.getSimpleName();
35 
36     /**
37      * Create a new file to hold a staged file.
38      *
39      * @param context The context of the caller
40      *
41      * @return A new file
42      */
43     @NonNull
getStagedFile(@onNull Context context)44     public static File getStagedFile(@NonNull Context context) throws IOException {
45         return File.createTempFile("package", ".apk", context.getNoBackupFilesDir());
46     }
47 
48     /**
49      * Get the file used to store the results of installs.
50      *
51      * @param context The context of the caller
52      *
53      * @return the file used to store the results of installs
54      */
55     @NonNull
getInstallStateFile(@onNull Context context)56     public static File getInstallStateFile(@NonNull Context context) {
57         return new File(context.getNoBackupFilesDir(), "install_results.xml");
58     }
59 
60     /**
61      * Get the file used to store the results of uninstalls.
62      *
63      * @param context The context of the caller
64      *
65      * @return the file used to store the results of uninstalls
66      */
67     @NonNull
getUninstallStateFile(@onNull Context context)68     public static File getUninstallStateFile(@NonNull Context context) {
69         return new File(context.getNoBackupFilesDir(), "uninstall_results.xml");
70     }
71 
72     @Override
onReceive(Context context, Intent intent)73     public void onReceive(Context context, Intent intent) {
74         long systemBootTime = System.currentTimeMillis() - SystemClock.elapsedRealtime();
75 
76         File[] filesOnBoot = context.getNoBackupFilesDir().listFiles();
77 
78         if (filesOnBoot == null) {
79             return;
80         }
81 
82         for (int i = 0; i < filesOnBoot.length; i++) {
83             File fileOnBoot = filesOnBoot[i];
84 
85             if (systemBootTime > fileOnBoot.lastModified()) {
86                 boolean wasDeleted = fileOnBoot.delete();
87                 if (!wasDeleted) {
88                     Log.w(LOG_TAG, "Could not delete " + fileOnBoot.getName() + " onBoot");
89                 }
90             } else {
91                 Log.w(LOG_TAG, fileOnBoot.getName() + " was created before onBoot broadcast was "
92                         + "received");
93             }
94         }
95     }
96 }
97