1 /* 2 * Copyright (c) 2018, 2020, 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 ReplaceCriticalClasses rcc = new ReplaceCriticalClasses(); 45 rcc.process(args); 46 } 47 48 public void process(String args[]) throws Throwable { 49 if (args.length == 0) { 50 // Dump the shared archive in case it was not generated during the JDK build. 51 // Put the archive at separate file to avoid clashes with concurrent tests. 52 CDSOptions opts = new CDSOptions() 53 .setXShareMode("dump") 54 .setArchiveName(ReplaceCriticalClasses.class.getName() + ".jsa") 55 .setUseVersion(false) 56 .addSuffix("-showversion") 57 .addSuffix("-Xlog:cds"); 58 CDSTestUtils.run(opts).assertNormalExit(""); 59 60 launchChildProcesses(getTests()); 61 } else if (args.length == 3 && args[0].equals("child")) { 62 Class klass = Class.forName(args[2].replace("/", ".")); 63 if (args[1].equals("-shared")) { 64 testInChild(true, klass); 65 } else if (args[1].equals("-notshared")) { 66 testInChild(false, klass); 67 } else { 68 throw new RuntimeException("Unknown child exec option " + args[1]); 69 } 70 return; 71 } else { 72 throw new RuntimeException("Usage: @run main/othervm/native ReplaceCriticalClasses"); 73 } 74 } 75 76 public String[] getTests() { 77 String tests[] = { 78 // CDS should be disabled -- these critical classes will be replaced 79 // because JvmtiExport::early_class_hook_env() is true. 80 "-early -notshared java/lang/Object", 81 "-early -notshared java/lang/String", 82 "-early -notshared java/lang/Cloneable", 83 "-early -notshared java/io/Serializable", 84 "-early -notshared java/lang/Module", 85 "-early -notshared java/lang/ModuleLayer", 86 87 // CDS should not be disabled -- these critical classes cannot be replaced because 88 // JvmtiExport::early_class_hook_env() is false. 89 "java/lang/Object", 90 "java/lang/String", 91 "java/lang/Cloneable", 92 "java/io/Serializable", 93 "java/lang/Module", 94 "java/lang/ModuleLayer", 95 96 // Replace classes that are loaded after JVMTI_PHASE_PRIMORDIAL. It's OK to replace 97 // such 98 // classes even when CDS is enabled. Nothing bad should happen. 99 "-notshared java/util/Locale", 100 "-notshared sun/util/locale/BaseLocale", 101 "-notshared java/lang/Readable", 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/Locale,XXX,XXX". 152 // The SimpleClassFileLoadHook agent would attempt to hook the java/util/Locale 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/Locale 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:cds", 169 "-XX:+UnlockDiagnosticVMOptions", 170 agent); 171 if (whitebox) { 172 opts.addSuffix("-XX:+WhiteBoxAPI", 173 "-Xbootclasspath/a:" + ClassFileInstaller.getJarPath("whitebox.jar")); 174 } 175 opts.addSuffix("-Xlog:cds,cds+heap"); 176 opts.addSuffix("ReplaceCriticalClasses", 177 "child", 178 shared, 179 klassName); 180 181 final boolean expectDisable = !early.equals(""); 182 final boolean checkSubgraph = subgraph; 183 final boolean expectShared = shared.equals("-shared"); 184 CDSTestUtils.run(opts).assertNormalExit(out -> { 185 if (expectDisable) { 186 out.shouldContain("UseSharedSpaces: CDS is disabled because early JVMTI ClassFileLoadHook is in use."); 187 System.out.println("CDS disabled as expected"); 188 } 189 if (checkSubgraph) { 190 if (expectShared) { 191 if (!out.getOutput().contains("UseSharedSpaces: Unable to map at required address in java heap")) { 192 out.shouldContain(subgraphInit); 193 // If the subgraph is successfully initialized, the specified shared class must not be rewritten. 194 out.shouldNotContain("Rewriting done."); 195 } 196 } else { 197 out.shouldNotContain(subgraphInit); 198 } 199 } 200 }); 201 } 202 203 static void testInChild(boolean shouldBeShared, Class klass) { 204 try { 205 WhiteBox wb = WhiteBox.getWhiteBox(); 206 207 if (shouldBeShared && !wb.isSharedClass(klass)) { 208 throw new RuntimeException(klass + " should be shared but but actually is not."); 209 } 210 if (!shouldBeShared && wb.isSharedClass(klass)) { 211 throw new RuntimeException(klass + " should not be shared but actually is."); 212 } 213 System.out.println("wb.isSharedClass(" + klass + "): " + wb.isSharedClass(klass) + " == " + shouldBeShared); 214 } catch (UnsatisfiedLinkError e) { 215 System.out.println("WhiteBox is disabled -- because test has -nowhitebox"); 216 } 217 218 String strings[] = { 219 // interned strings from j.l.Object 220 "@", 221 "nanosecond timeout value out of range", 222 "timeoutMillis value is negative", 223 224 // interned strings from j.l.Integer 225 "0", 226 "0X", 227 "0x", 228 "int" 229 }; 230 231 // Make sure the interned string table is same 232 for (String s : strings) { 233 String i = s.intern(); 234 if (s != i) { 235 throw new RuntimeException("Interned string mismatch: \"" + s + "\" @ " + System.identityHashCode(s) + 236 " vs \"" + i + "\" @ " + System.identityHashCode(i)); 237 } 238 } 239 // We have tried to use ClassFileLoadHook to replace critical library classes (which may 240 // may not have succeeded, depending on whether the agent has requested 241 // can_generate_all_class_hook_events/can_generate_early_class_hook_events capabilities). 242 // 243 // In any case, the JVM should have started properly (perhaps with CDS disabled) and 244 // the above operations should succeed. 245 System.out.println("If I can come to here without crashing, things should be OK"); 246 } 247 }