1 /*
2  * Copyright (C) 2019 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 import art.Redefinition;
18 import java.lang.invoke.*;
19 import java.lang.reflect.Field;
20 import java.util.Base64;
21 
22 public class Main {
23   public static final class Transform {
24     static {
25     }
26 
27     public static Object foo = null;
28   }
29 
30   /* Base64 encoded dex bytes for:
31    *
32    * public static final class Transform {
33    *   static {}
34    *   public static Object bar = null;
35    *   public static Object foo = null;
36    * }
37    */
38   public static final byte[] DEX_BYTES =
39       Base64.getDecoder()
40           .decode(
41               "ZGV4CjAzNQCjkRjcSr1RJO8FnnCjHV/8h6keJP/+P3WQAwAAcAAAAHhWNBIAAAAAAAAAANgCAAAQ"
42                   + "AAAAcAAAAAYAAACwAAAAAQAAAMgAAAACAAAA1AAAAAMAAADkAAAAAQAAAPwAAAB0AgAAHAEAAFwB"
43                   + "AABmAQAAbgEAAIABAACIAQAArAEAAMwBAADgAQAA6wEAAPYBAAD5AQAABgIAAAsCAAAQAgAAFgIA"
44                   + "AB0CAAACAAAAAwAAAAQAAAAFAAAABgAAAAkAAAAJAAAABQAAAAAAAAAAAAQACwAAAAAABAAMAAAA"
45                   + "AAAAAAAAAAAAAAAAAQAAAAQAAAABAAAAAAAAABEAAAAEAAAAAAAAAAcAAADIAgAApAIAAAAAAAAB"
46                   + "AAAAAAAAAFABAAAGAAAAEgBpAAAAaQABAA4AAQABAAEAAABVAQAABAAAAHAQAgAAAA4ABwAOPAAF"
47                   + "AA4AAAAACDxjbGluaXQ+AAY8aW5pdD4AEExNYWluJFRyYW5zZm9ybTsABkxNYWluOwAiTGRhbHZp"
48                   + "ay9hbm5vdGF0aW9uL0VuY2xvc2luZ0NsYXNzOwAeTGRhbHZpay9hbm5vdGF0aW9uL0lubmVyQ2xh"
49                   + "c3M7ABJMamF2YS9sYW5nL09iamVjdDsACU1haW4uamF2YQAJVHJhbnNmb3JtAAFWAAthY2Nlc3NG"
50                   + "bGFncwADYmFyAANmb28ABG5hbWUABXZhbHVlAHZ+fkQ4eyJjb21waWxhdGlvbi1tb2RlIjoiZGVi"
51                   + "dWciLCJtaW4tYXBpIjoxLCJzaGEtMSI6IjI4YmNlZjUwYWM4NTk3Y2YyMmU4OTJiMWJjM2EzYjky"
52                   + "Yjc0ZTcwZTkiLCJ2ZXJzaW9uIjoiMS42LjMyLWRldiJ9AAICAQ4YAQIDAgoEGQ0XCAIAAgAACQEJ"
53                   + "AIiABJwCAYGABLgCAAAAAAIAAACVAgAAmwIAALwCAAAAAAAAAAAAAAAAAAAPAAAAAAAAAAEAAAAA"
54                   + "AAAAAQAAABAAAABwAAAAAgAAAAYAAACwAAAAAwAAAAEAAADIAAAABAAAAAIAAADUAAAABQAAAAMA"
55                   + "AADkAAAABgAAAAEAAAD8AAAAASAAAAIAAAAcAQAAAyAAAAIAAABQAQAAAiAAABAAAABcAQAABCAA"
56                   + "AAIAAACVAgAAACAAAAEAAACkAgAAAxAAAAIAAAC4AgAABiAAAAEAAADIAgAAABAAAAEAAADYAgAA");
57 
main(String[] args)58   public static void main(String[] args) throws Exception, Throwable {
59     System.loadLibrary(args[0]);
60     Field f = Transform.class.getDeclaredField("foo");
61     Transform.foo = "THIS IS A FOO VALUE";
62     System.out.println("Foo value is " + f.get(null));
63     final int max_depth = 10;
64     Object[] results = new Object[max_depth];
65     Runnable res =
66         () -> {
67           Redefinition.doCommonStructuralClassRedefinition(Transform.class, DEX_BYTES);
68         };
69     for (int i = 0; i < max_depth; i++) {
70       final Runnable next = res;
71       final int id = i;
72       res =
73           () -> {
74             try {
75               results[id] = NativeFieldScopeCheck(f, next).invokeExact();
76             } catch (Throwable t) {
77               throw new Error("Failed!", t);
78             }
79           };
80     }
81     res.run();
82     for (int i = 0; i < max_depth; i++) {
83       System.out.println("Result at depth " + i + ": " + results[i]);
84     }
85   }
86 
87   // Hold the field as a ArtField, run the 'test' function, turn the ArtField into a MethodHandle
88   // directly and return that.
NativeFieldScopeCheck(Field in, Runnable test)89   public static native MethodHandle NativeFieldScopeCheck(Field in, Runnable test);
90 }
91