1 /*
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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 jdk.test.whitebox.WhiteBox
31 * @run driver jdk.test.lib.helpers.ClassFileInstaller -jar whitebox.jar jdk.test.whitebox.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 jdk.test.lib.helpers.ClassFileInstaller;
41 import jdk.test.whitebox.WhiteBox;
42
43 public class ReplaceCriticalClasses {
44 public static void main(String args[]) throws Throwable {
45 ReplaceCriticalClasses rcc = new ReplaceCriticalClasses();
46 rcc.process(args);
47 }
48
49 public void process(String args[]) throws Throwable {
50 if (args.length == 0) {
51 // Add an extra class to provoke JDK-8262376. This will be ignored if this class doesn't exist
52 // in the JDK that's being tested (e.g., if the "jdk.localedata" module is somehow missing).
53 String extraClasses[] = {"sun/util/resources/cldr/provider/CLDRLocaleDataMetaInfo"};
54
55 // Dump the shared archive in case it was not generated during the JDK build.
56 // Put the archive at separate file to avoid clashes with concurrent tests.
57 CDSOptions opts = new CDSOptions()
58 .setClassList(extraClasses)
59 .setArchiveName(ReplaceCriticalClasses.class.getName() + ".jsa");
60 CDSTestUtils.createArchiveAndCheck(opts);
61
62 launchChildProcesses(getTests());
63 } else if (args.length == 3 && args[0].equals("child")) {
64 Class klass = Class.forName(args[2].replace("/", "."));
65 if (args[1].equals("-shared")) {
66 testInChild(true, klass);
67 } else if (args[1].equals("-notshared")) {
68 testInChild(false, klass);
69 } else {
70 throw new RuntimeException("Unknown child exec option " + args[1]);
71 }
72 return;
73 } else {
74 throw new RuntimeException("Usage: @run main/othervm/native ReplaceCriticalClasses");
75 }
76 }
77
78 public String[] getTests() {
79 String tests[] = {
80 // CDS should be disabled -- these critical classes will be replaced
81 // because JvmtiExport::early_class_hook_env() is true.
82 "-early -notshared java/lang/Object",
83 "-early -notshared java/lang/String",
84 "-early -notshared java/lang/Cloneable",
85 "-early -notshared java/io/Serializable",
86 "-early -notshared java/lang/Module",
87 "-early -notshared java/lang/ModuleLayer",
88
89 // CDS should not be disabled -- these critical classes cannot be replaced because
90 // JvmtiExport::early_class_hook_env() is false.
91 "java/lang/Object",
92 "java/lang/String",
93 "java/lang/Cloneable",
94 "java/io/Serializable",
95 "java/lang/Module",
96 "java/lang/ModuleLayer",
97
98 // Replace classes that are loaded after JVMTI_PHASE_PRIMORDIAL. It's OK to replace
99 // such
100 // classes even when CDS is enabled. Nothing bad should happen.
101 "-notshared java/util/Calendar",
102 };
103 return tests;
104 }
105
106 static void launchChildProcesses(String tests[]) throws Throwable {
107 int n = 0;
108 for (String s : tests) {
109 System.out.println("Test case[" + (n++) + "] = \"" + s + "\"");
110 String args[] = s.split("\\s+"); // split by space character
111 launchChild(args);
112 }
113 }
114
115 static void launchChild(String args[]) throws Throwable {
116 if (args.length < 1) {
117 throw new RuntimeException("Invalid test case. Should be <-early> <-subgraph> <-notshared> <-nowhitebox> klassName subgraphKlass");
118 }
119 String klassName = null;
120 String subgraphKlass = null;
121 String early = "";
122 boolean subgraph = false;
123 boolean whitebox = true;
124 String shared = "-shared";
125
126 for (int i=0; i<args.length-1; i++) {
127 String opt = args[i];
128 if (opt.equals("-early")) {
129 early = "-early,";
130 } else if (opt.equals("-subgraph")) {
131 subgraph = true;
132 } else if (opt.equals("-nowhitebox")) {
133 whitebox = false;
134 } else if (opt.equals("-notshared")) {
135 shared = opt;
136 } else {
137 if (!subgraph) {
138 throw new RuntimeException("Unknown option: " + opt);
139 }
140 }
141 }
142 if (subgraph) {
143 klassName = args[args.length-2];
144 subgraphKlass = args[args.length-1];
145 } else {
146 klassName = args[args.length-1];
147 }
148 Class.forName(klassName.replace("/", ".")); // make sure it's a valid class
149 final String subgraphInit = "initialize_from_archived_subgraph " + subgraphKlass;
150
151 // We will pass an option like "-agentlib:SimpleClassFileLoadHook=java/util/Calendar,XXX,XXX".
152 // The SimpleClassFileLoadHook agent would attempt to hook the java/util/Calendar class
153 // but leave the class file bytes unchanged (it replaces all bytes "XXX" with "XXX", i.e.,
154 // a no-op). JVMTI doesn't check the class file bytes returned by the agent, so as long
155 // as the agent returns a buffer, it will not load the class from CDS, and will instead
156 // load the class by parsing the buffer.
157 //
158 // Note that for safety we don't change the contents of the class file bytes. If in the
159 // future JVMTI starts checking the contents of the class file bytes, this test would need
160 // to be updated. (You'd see the test case with java/util/Calendar staring to fail).
161 String agent = "-agentlib:SimpleClassFileLoadHook=" + early + klassName + ",XXX,XXX";
162
163 CDSOptions opts = (new CDSOptions())
164 .setXShareMode("auto")
165 .setArchiveName(ReplaceCriticalClasses.class.getName() + ".jsa")
166 .setUseVersion(false)
167 .addSuffix("-showversion",
168 "-Xlog:aot",
169 "-Xlog:cds",
170 "-XX:+UnlockDiagnosticVMOptions",
171 agent);
172 if (whitebox) {
173 opts.addSuffix("-XX:+WhiteBoxAPI",
174 "-Xbootclasspath/a:" + ClassFileInstaller.getJarPath("whitebox.jar"));
175 }
176 opts.addSuffix("-Xlog:aot,aot+heap,cds");
177 opts.addSuffix("ReplaceCriticalClasses",
178 "child",
179 shared,
180 klassName);
181
182 final boolean expectDisable = !early.equals("");
183 final boolean checkSubgraph = subgraph;
184 final boolean expectShared = shared.equals("-shared");
185 CDSTestUtils.run(opts).assertNormalExit(out -> {
186 if (expectDisable) {
187 out.shouldContain("CDS is disabled because early JVMTI ClassFileLoadHook is in use.");
188 System.out.println("CDS disabled as expected");
189 }
190 if (checkSubgraph) {
191 if (expectShared) {
192 if (!out.getOutput().contains("Unable to map at required address in java heap")) {
193 out.shouldContain(subgraphInit);
194 // If the subgraph is successfully initialized, the specified shared class must not be rewritten.
195 out.shouldNotContain("Rewriting done.");
196 }
197 } else {
198 out.shouldNotContain(subgraphInit);
199 }
200 }
201 });
202 }
203
204 static void testInChild(boolean shouldBeShared, Class klass) {
205 try {
206 WhiteBox wb = WhiteBox.getWhiteBox();
207
208 if (shouldBeShared && !wb.isSharedClass(klass)) {
209 throw new RuntimeException(klass + " should be shared but but actually is not.");
210 }
211 if (!shouldBeShared && wb.isSharedClass(klass)) {
212 throw new RuntimeException(klass + " should not be shared but actually is.");
213 }
214 System.out.println("wb.isSharedClass(" + klass + "): " + wb.isSharedClass(klass) + " == " + shouldBeShared);
215 } catch (UnsatisfiedLinkError e) {
216 System.out.println("WhiteBox is disabled -- because test has -nowhitebox");
217 }
218
219 String strings[] = {
220 // interned strings from j.l.Object
221 "@",
222 "nanosecond timeout value out of range",
223 "timeoutMillis value is negative",
224
225 // interned strings from j.l.Integer
226 "0",
227 "0X",
228 "0x",
229 "int"
230 };
231
232 // Make sure the interned string table is same
233 for (String s : strings) {
234 String i = s.intern();
235 if (s != i) {
236 throw new RuntimeException("Interned string mismatch: \"" + s + "\" @ " + System.identityHashCode(s) +
237 " vs \"" + i + "\" @ " + System.identityHashCode(i));
238 }
239 }
240 // We have tried to use ClassFileLoadHook to replace critical library classes (which may
241 // may not have succeeded, depending on whether the agent has requested
242 // can_generate_all_class_hook_events/can_generate_early_class_hook_events capabilities).
243 //
244 // In any case, the JVM should have started properly (perhaps with CDS disabled) and
245 // the above operations should succeed.
246 System.out.println("If I can come to here without crashing, things should be OK");
247 }
248 }