1 /*
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  7  * published by the Free Software Foundation.
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 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).
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 18  *
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 20  * or visit www.oracle.com if you need additional information or have any
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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/Locale",
102             "-notshared sun/util/locale/BaseLocale",
103         };
104         return tests;
105     }
106 
107     static void launchChildProcesses(String tests[]) throws Throwable {
108         int n = 0;
109         for (String s : tests) {
110             System.out.println("Test case[" + (n++) + "] = \"" + s + "\"");
111             String args[] = s.split("\\s+"); // split by space character
112             launchChild(args);
113         }
114     }
115 
116     static void launchChild(String args[]) throws Throwable {
117         if (args.length < 1) {
118             throw new RuntimeException("Invalid test case. Should be <-early> <-subgraph> <-notshared> <-nowhitebox> klassName subgraphKlass");
119         }
120         String klassName = null;
121         String subgraphKlass = null;
122         String early = "";
123         boolean subgraph = false;
124         boolean whitebox = true;
125         String shared = "-shared";
126 
127         for (int i=0; i<args.length-1; i++) {
128             String opt = args[i];
129             if (opt.equals("-early")) {
130                 early = "-early,";
131             } else if (opt.equals("-subgraph")) {
132                 subgraph = true;
133             } else if (opt.equals("-nowhitebox")) {
134                 whitebox = false;
135             } else if (opt.equals("-notshared")) {
136                 shared = opt;
137             } else {
138               if (!subgraph) {
139                 throw new RuntimeException("Unknown option: " + opt);
140               }
141             }
142         }
143         if (subgraph) {
144           klassName = args[args.length-2];
145           subgraphKlass = args[args.length-1];
146         } else {
147           klassName = args[args.length-1];
148         }
149         Class.forName(klassName.replace("/", ".")); // make sure it's a valid class
150         final String subgraphInit = "initialize_from_archived_subgraph " + subgraphKlass;
151 
152         // We will pass an option like "-agentlib:SimpleClassFileLoadHook=java/util/Locale,XXX,XXX".
153         // The SimpleClassFileLoadHook agent would attempt to hook the java/util/Locale class
154         // but leave the class file bytes unchanged (it replaces all bytes "XXX" with "XXX", i.e.,
155         // a no-op). JVMTI doesn't check the class file bytes returned by the agent, so as long
156         // as the agent returns a buffer, it will not load the class from CDS, and will instead
157         // load the class by parsing the buffer.
158         //
159         // Note that for safety we don't change the contents of the class file bytes. If in the
160         // future JVMTI starts checking the contents of the class file bytes, this test would need
161         // to be updated. (You'd see the test case with java/util/Locale staring to fail).
162         String agent = "-agentlib:SimpleClassFileLoadHook=" + early + klassName + ",XXX,XXX";
163 
164         CDSOptions opts = (new CDSOptions())
165             .setXShareMode("auto")
166             .setArchiveName(ReplaceCriticalClasses.class.getName() + ".jsa")
167             .setUseVersion(false)
168             .addSuffix("-showversion",
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:cds,cds+heap");
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 }