1 /*
2  * Copyright (C) 2018 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.settingslib.license;
18 
19 import android.content.Context;
20 import android.util.Log;
21 
22 import com.android.settingslib.R;
23 import com.android.settingslib.utils.AsyncLoaderCompat;
24 
25 import java.io.File;
26 import java.util.ArrayList;
27 import java.util.List;
28 
29 /**
30  * LicenseHtmlLoader is a loader which loads a license html file from default license xml files.
31  */
32 public class LicenseHtmlLoaderCompat extends AsyncLoaderCompat<File> {
33     private static final String TAG = "LicenseHtmlLoaderCompat";
34 
35     static final String[] DEFAULT_LICENSE_XML_PATHS = {
36             "/system/etc/NOTICE.xml.gz",
37             "/vendor/etc/NOTICE.xml.gz",
38             "/odm/etc/NOTICE.xml.gz",
39             "/oem/etc/NOTICE.xml.gz",
40             "/product/etc/NOTICE.xml.gz",
41             "/system_ext/etc/NOTICE.xml.gz",
42             "/vendor_dlkm/etc/NOTICE.xml.gz",
43             "/odm_dlkm/etc/NOTICE.xml.gz",
44     };
45     static final String NOTICE_HTML_FILE_NAME = "NOTICE.html";
46 
47     private final Context mContext;
48 
LicenseHtmlLoaderCompat(Context context)49     public LicenseHtmlLoaderCompat(Context context) {
50         super(context);
51         mContext = context;
52     }
53 
54     @Override
loadInBackground()55     public File loadInBackground() {
56         return generateHtmlFromDefaultXmlFiles();
57     }
58 
59     @Override
onDiscardResult(File f)60     protected void onDiscardResult(File f) {
61     }
62 
generateHtmlFromDefaultXmlFiles()63     private File generateHtmlFromDefaultXmlFiles() {
64         final List<File> xmlFiles = getVaildXmlFiles();
65         if (xmlFiles.isEmpty()) {
66             Log.e(TAG, "No notice file exists.");
67             return null;
68         }
69 
70         File cachedHtmlFile = getCachedHtmlFile(mContext);
71         if (!isCachedHtmlFileOutdated(xmlFiles, cachedHtmlFile)
72                 || generateHtmlFile(mContext, xmlFiles, cachedHtmlFile)) {
73             return cachedHtmlFile;
74         }
75 
76         return null;
77     }
78 
getVaildXmlFiles()79     private List<File> getVaildXmlFiles() {
80         final List<File> xmlFiles = new ArrayList();
81         for (final String xmlPath : DEFAULT_LICENSE_XML_PATHS) {
82             File file = new File(xmlPath);
83             if (file.exists() && file.length() != 0) {
84                 xmlFiles.add(file);
85             }
86         }
87         return xmlFiles;
88     }
89 
getCachedHtmlFile(Context context)90     private File getCachedHtmlFile(Context context) {
91         return new File(context.getCacheDir(), NOTICE_HTML_FILE_NAME);
92     }
93 
isCachedHtmlFileOutdated(List<File> xmlFiles, File cachedHtmlFile)94     private boolean isCachedHtmlFileOutdated(List<File> xmlFiles, File cachedHtmlFile) {
95         boolean outdated = true;
96         if (cachedHtmlFile.exists() && cachedHtmlFile.length() != 0) {
97             outdated = false;
98             for (File file : xmlFiles) {
99                 if (cachedHtmlFile.lastModified() < file.lastModified()) {
100                     outdated = true;
101                     break;
102                 }
103             }
104         }
105         return outdated;
106     }
107 
generateHtmlFile(Context context, List<File> xmlFiles, File htmlFile)108     private boolean generateHtmlFile(Context context, List<File> xmlFiles, File htmlFile) {
109         return LicenseHtmlGeneratorFromXml.generateHtml(xmlFiles, htmlFile,
110                 context.getString(R.string.notice_header));
111     }
112 }
113