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 android.signature.cts.api;
18 
19 import android.os.Debug;
20 import android.signature.cts.ClassProvider;
21 import android.signature.cts.DexField;
22 import android.signature.cts.DexMethod;
23 import android.signature.cts.DexMember;
24 import dalvik.system.BaseDexClassLoader;
25 
26 import java.io.File;
27 import java.io.FileInputStream;
28 import java.io.FileOutputStream;
29 import java.io.InputStream;
30 import java.io.OutputStream;
31 import java.util.Arrays;
32 import java.util.stream.Stream;
33 
34 @SuppressWarnings("deprecation")
35 public class BootClassPathClassesProvider extends ClassProvider {
36     private static boolean sJvmtiAttached = false;
37 
38     @Override
getAllClasses()39     public Stream<Class<?>> getAllClasses() {
40         maybeAttachJvmtiAgent();
41         return Arrays.stream(getClassloaderDescriptors(Object.class.getClassLoader()))
42                 .map(descriptor -> {
43                     String classname = descriptor.replace('/', '.');
44                     // omit L and ; at the front and at the end
45                     return classname.substring(1, classname.length() - 1);
46                 })
47                 .map(classname -> {
48                     try {
49                         return getClass(classname);
50                     } catch (ClassNotFoundException e) {
51                         throw new RuntimeException("Cannot load " + classname, e);
52                     }
53                 });
54     }
55 
56     @Override
getAllMembers(Class<?> klass)57     public Stream<DexMember> getAllMembers(Class<?> klass) {
58         maybeAttachJvmtiAgent();
59 
60         String[][] field_infos = getClassMemberNamesAndTypes(klass, /* fields */ true);
61         String[][] method_infos = getClassMemberNamesAndTypes(klass, /* fields */ false);
62         if (field_infos.length != 2 || field_infos[0].length != field_infos[1].length ||
63             method_infos.length != 2 || method_infos[0].length != method_infos[1].length) {
64           throw new RuntimeException("Invalid result from getClassMemberNamesAndTypes");
65         }
66 
67         String klass_desc = "L" + klass.getName().replace('.', '/') + ";";
68         DexMember[] members = new DexMember[field_infos[0].length + method_infos[0].length];
69         for (int i = 0; i < field_infos[0].length; i++) {
70             members[i] = new DexField(klass_desc, field_infos[0][i], field_infos[1][i], null);
71         }
72         for (int i = 0; i < method_infos[0].length; i++) {
73             members[i + field_infos[0].length] =
74                 new DexMethod(klass_desc, method_infos[0][i], method_infos[1][i], null);
75         }
76         return Arrays.stream(members);
77     }
78 
maybeAttachJvmtiAgent()79     private static void maybeAttachJvmtiAgent() {
80       if (!sJvmtiAttached) {
81           try {
82               Debug.attachJvmtiAgent(copyAgentToFile("classdescriptors").getAbsolutePath(), null,
83                       BootClassPathClassesProvider.class.getClassLoader());
84               sJvmtiAttached = true;
85               initialize();
86           } catch (Exception e) {
87               throw new RuntimeException("Error while attaching JVMTI agent", e);
88           }
89       }
90     }
91 
copyAgentToFile(String lib)92     private static File copyAgentToFile(String lib) throws Exception {
93         ClassLoader cl = BootClassPathClassesProvider.class.getClassLoader();
94 
95         File copiedAgent = File.createTempFile("agent", ".so");
96         try (InputStream is = new FileInputStream(
97                 ((BaseDexClassLoader) cl).findLibrary(lib))) {
98             try (OutputStream os = new FileOutputStream(copiedAgent)) {
99                 byte[] buffer = new byte[64 * 1024];
100 
101                 while (true) {
102                     int numRead = is.read(buffer);
103                     if (numRead == -1) {
104                         break;
105                     }
106                     os.write(buffer, 0, numRead);
107                 }
108             }
109         }
110         return copiedAgent;
111     }
112 
initialize()113     private static native void initialize();
114 
getClassloaderDescriptors(ClassLoader loader)115     private static native String[] getClassloaderDescriptors(ClassLoader loader);
getClassMemberNamesAndTypes(Class<?> klass, boolean getFields)116     private static native String[][] getClassMemberNamesAndTypes(Class<?> klass, boolean getFields);
117 }
118