NativeMethodPrefixAgent.java revision 12973:2e63fa2efdb1 
1/*
2 * Copyright (c) 2005, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24/**
25 * @test
26 * @bug 6263319
27 * @summary test setNativeMethodPrefix
28 * @author Robert Field, Sun Microsystems
29 *
30 * @modules java.base/jdk.internal.org.objectweb.asm
31 *          java.management
32 *          java.instrument
33 * @run shell/timeout=240 MakeJAR2.sh NativeMethodPrefixAgent NativeMethodPrefixApp 'Can-Retransform-Classes: true' 'Can-Set-Native-Method-Prefix: true'
34 * @run main/othervm -javaagent:NativeMethodPrefixAgent.jar NativeMethodPrefixApp
35 */
36
37import java.lang.instrument.*;
38import java.security.ProtectionDomain;
39import java.io.*;
40
41import asmlib.*;
42
43class NativeMethodPrefixAgent {
44
45    static ClassFileTransformer t0, t1, t2;
46    static Instrumentation inst;
47
48    static class Tr implements ClassFileTransformer {
49        final String trname;
50        final int transformId;
51
52        Tr(int transformId) {
53            this.trname = "tr" + transformId;
54            this.transformId = transformId;
55        }
56
57        public byte[]
58        transform(
59            ClassLoader loader,
60            String className,
61            Class<?> classBeingRedefined,
62            ProtectionDomain    protectionDomain,
63            byte[] classfileBuffer) {
64            boolean redef = classBeingRedefined != null;
65            System.out.println(trname + ": " +
66                               (redef? "Retransforming " : "Loading ") + className);
67            if (className != null) {
68                try {
69                    byte[] newcf = Instrumentor.instrFor(classfileBuffer)
70                                   .addNativeMethodTrackingInjection(
71                                        "wrapped_" + trname + "_",
72                                        (h)->{
73                                            h.push(h.getName());
74                                            h.push(transformId);
75                                            h.invokeStatic("bootreporter/StringIdCallbackReporter", "tracker", "(Ljava/lang/String;I)V", false);
76                                        })
77                                   .apply();
78                    /*** debugging ...
79                    if (newcf != null) {
80                        String fname = trname + (redef?"_redef" : "") + "/" + className;
81                        System.err.println("dumping to: " + fname);
82                        write_buffer(fname + "_before.class", classfileBuffer);
83                        write_buffer(fname + "_instr.class", newcf);
84                    }
85                    ***/
86
87                    return redef? null : newcf;
88                } catch (Throwable ex) {
89                    System.err.println("ERROR: Injection failure: " + ex);
90                    ex.printStackTrace();
91                    System.err.println("Returning bad class file, to cause test failure");
92                    return new byte[0];
93                }
94            }
95            return null;
96        }
97
98    }
99
100    // for debugging
101    static void write_buffer(String fname, byte[]buffer) {
102        try {
103            File f = new File(fname);
104            if (!f.getParentFile().exists()) {
105                f.getParentFile().mkdirs();
106            }
107            try (FileOutputStream outStream = new FileOutputStream(f)) {
108                outStream.write(buffer, 0, buffer.length);
109            }
110        } catch (IOException ex) {
111            System.err.println("EXCEPTION in write_buffer: " + ex);
112        }
113    }
114
115    public static void
116    premain (String agentArgs, Instrumentation instArg)
117        throws IOException, IllegalClassFormatException,
118        ClassNotFoundException, UnmodifiableClassException {
119        inst = instArg;
120        System.out.println("Premain");
121
122        t1 = new Tr(1);
123        t2 = new Tr(2);
124        t0 = new Tr(0);
125        inst.addTransformer(t1, true);
126        inst.addTransformer(t2, false);
127        inst.addTransformer(t0, true);
128        instArg.setNativeMethodPrefix(t0, "wrapped_tr0_");
129        instArg.setNativeMethodPrefix(t1, "wrapped_tr1_");
130        instArg.setNativeMethodPrefix(t2, "wrapped_tr2_");
131
132        // warm up: cause load of transformer classes before used during class load
133        instArg.retransformClasses(Runtime.class);
134    }
135}
136