1 /*
2 * Copyright (c) 2018, 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 /*
26 * @test
27 * @summary Tests how CDS works when critical library classes are replaced with JVMTI ClassFileLoadHook
28 * @library /test/lib
29 * @requires vm.cds
30 * @build sun.hotspot.WhiteBox
31 * @run driver ClassFileInstaller -jar whitebox.jar sun.hotspot.WhiteBox
32 * @run main/othervm/native ReplaceCriticalClasses
33 */
34
35 import java.util.regex.Matcher;
36 import java.util.regex.Pattern;
37 import jdk.test.lib.cds.CDSTestUtils;
38 import jdk.test.lib.cds.CDSOptions;
39 import jdk.test.lib.process.OutputAnalyzer;
40 import sun.hotspot.WhiteBox;
41
42 public class ReplaceCriticalClasses {
43 public static void main(String args[]) throws Throwable {
44 if (args.length == 0) {
45 launchChildProcesses();
46 } else if (args.length == 3 && args[0].equals("child")) {
47 Class klass = Class.forName(args[2].replace("/", "."));
48 if (args[1].equals("-shared")) {
49 testInChild(true, klass);
50 } else if (args[1].equals("-notshared")) {
51 testInChild(false, klass);
52 } else {
53 throw new RuntimeException("Unknown child exec option " + args[1]);
54 }
55 return;
56 } else {
57 throw new RuntimeException("Usage: @run main/othervm/native ReplaceCriticalClasses");
58 }
59 }
60
61 static void launchChildProcesses() throws Throwable {
62 String tests[] = {
63 // CDS should be disabled -- these critical classes will be replaced
64 // because JvmtiExport::early_class_hook_env() is true.
65 "-early -notshared java/lang/Object",
66 "-early -notshared java/lang/String",
67 "-early -notshared java/lang/Cloneable",
68 "-early -notshared java/io/Serializable",
69
70 // CDS should not be disabled -- these critical classes cannot be replaced because JvmtiExport::early_class_hook_env() is false.
71 "java/lang/Object",
72 "java/lang/String",
73 "java/lang/Cloneable",
74 "java/io/Serializable",
75
76 // Try to replace classes that are used by the archived subgraph graphs.
77 "-subgraph java/util/ArrayList",
78 "-subgraph java/lang/module/ResolvedModule",
79
80 // Replace classes that are loaded after JVMTI_PHASE_PRIMORDIAL. It's OK to replace such
81 // classes even when CDS is enabled. Nothing bad should happen.
82 "-notshared jdk/internal/vm/PostVMInitHook",
83 "-notshared java/util/Locale",
84 "-notshared sun/util/locale/BaseLocale",
85 "-notshared java/lang/Readable",
86 };
87
88 int n = 0;
89 for (String s : tests) {
90 System.out.println("Test case[" + (n++) + "] = \"" + s + "\"");
91 String args[] = s.split("\\s+"); // split by space character
92 launchChild(args);
93 }
94 }
95
96 static void launchChild(String args[]) throws Throwable {
97 if (args.length < 1) {
98 throw new RuntimeException("Invalid test case. Should be <-early> <-subgraph> <-notshared> klassName");
99 }
100 String klassName = null;
101 String early = "";
102 boolean subgraph = false;
103 String shared = "-shared";
104
105 for (int i=0; i<args.length-1; i++) {
106 String opt = args[i];
107 if (opt.equals("-early")) {
108 early = "-early,";
109 } else if (opt.equals("-subgraph")) {
110 subgraph = true;
111 } else if (opt.equals("-notshared")) {
112 shared = opt;
113 } else {
114 throw new RuntimeException("Unknown option: " + opt);
115 }
116 }
117 klassName = args[args.length-1];
118 Class.forName(klassName.replace("/", ".")); // make sure it's a valid class
119
120 // We will pass an option like "-agentlib:SimpleClassFileLoadHook=java/util/Locale,XXX,XXX".
121 // The SimpleClassFileLoadHook agent would attempt to hook the java/util/Locale class
122 // but leave the class file bytes unchanged (it replaces all bytes "XXX" with "XXX", i.e.,
123 // a no-op). JVMTI doesn't check the class file bytes returned by the agent, so as long
124 // as the agent returns a buffer, it will not load the class from CDS, and will instead
125 // load the class by parsing the buffer.
126 //
127 // Note that for safety we don't change the contents of the class file bytes. If in the
128 // future JVMTI starts checking the contents of the class file bytes, this test would need
129 // to be updated. (You'd see the test case with java/util/Locale staring to fail).
130 String agent = "-agentlib:SimpleClassFileLoadHook=" + early + klassName + ",XXX,XXX";
131
132 CDSOptions opts = new CDSOptions();
133 opts.setXShareMode("auto")
134 .addSuffix("-showversion")
135 .addSuffix("-Xlog:cds")
136 .addSuffix("-XX:+UnlockDiagnosticVMOptions")
137 .addSuffix(agent)
138 .addSuffix("-XX:+WhiteBoxAPI")
139 .addSuffix("-Xbootclasspath/a:" + ClassFileInstaller.getJarPath("whitebox.jar"));
140
141 if (subgraph) {
142 opts.addSuffix("-Xlog:cds+heap");
143 opts.addSuffix("-Xlog:class+load");
144 }
145
146 opts.addSuffix("ReplaceCriticalClasses")
147 .addSuffix("child")
148 .addSuffix(shared)
149 .addSuffix(klassName)
150 .setUseSystemArchive(true)
151 .setUseVersion(false);
152
153 final boolean expectDisable = !early.equals("");
154 final boolean checkSubgraph = subgraph;
155 CDSTestUtils.run(opts).assertNormalExit(out -> {
156 if (expectDisable) {
157 out.shouldContain("UseSharedSpaces: CDS is disabled because early JVMTI ClassFileLoadHook is in use.");
158 System.out.println("CDS disabled as expected");
159 }
160 if (checkSubgraph && false) {
161 // As of 2018/10/21 the classes in the archived subgraphs won't be
162 // replaced because all archived subgraphs were loaded in JVMTI_PHASE_PRIMORDIAL.
163 //
164 // This is the first class to be loaded after JVMTI has exited JVMTI_PHASE_PRIMORDIAL.
165 // Make sure no subgraphs are loaded afterwards.
166 //
167 // Can't use out.shouldNotMatch() because that doesn't match across multiple lines.
168 String firstNonPrimordialClass = "jdk.jfr.internal.EventWriter";
169 String regexp = firstNonPrimordialClass + ".*initialize_from_archived_subgraph";
170 Pattern regex = Pattern.compile(regexp, Pattern.DOTALL);
171 Matcher matcher = regex.matcher(out.getStdout());
172 if (matcher.find()) {
173 out.reportDiagnosticSummary();
174 throw new RuntimeException("'" + regexp
175 + "' found in stdout: '" + matcher.group() + "' \n");
176 }
177 }
178 });
179 }
180
181 static void testInChild(boolean shouldBeShared, Class klass) {
182 WhiteBox wb = WhiteBox.getWhiteBox();
183
184 if (shouldBeShared && !wb.isSharedClass(klass)) {
185 throw new RuntimeException(klass + " should be shared but but actually is not.");
186 }
187 if (!shouldBeShared && wb.isSharedClass(klass)) {
188 throw new RuntimeException(klass + " should not be shared but actually is.");
189 }
190 System.out.println("wb.isSharedClass(klass): " + wb.isSharedClass(klass) + " == " + shouldBeShared);
191
192 String strings[] = {
193 // interned strings from j.l.Object
194 "@",
195 "nanosecond timeout value out of range",
196 "timeoutMillis value is negative",
197
198 // interned strings from j.l.Integer
199 "0",
200 "0X",
201 "0x",
202 "int"
203 };
204
205 // Make sure the interned string table is same
206 for (String s : strings) {
207 String i = s.intern();
208 if (s != i) {
209 throw new RuntimeException("Interned string mismatch: \"" + s + "\" @ " + System.identityHashCode(s) +
210 " vs \"" + i + "\" @ " + System.identityHashCode(i));
211 }
212 }
213 // We have tried to use ClassFileLoadHook to replace critical library classes (which may
214 // may not have succeeded, depending on whether the agent has requested
215 // can_generate_all_class_hook_events/can_generate_early_class_hook_events capabilities).
216 //
217 // In any case, the JVM should have started properly (perhaps with CDS disabled) and
218 // the above operations should succeed.
219 System.out.println("If I can come to here without crashing, things should be OK");
220 }
221 }