jdk-sandbox: comparison test/hotspot/jtreg/runtime/appcds/jvmti/InstrumentationTest.java

equal deleted inserted replaced

-:dc66ada06693
+:f98f158c1db8
 /*
-* Copyright (c) 2014, 2017, Oracle and/or its affiliates. All rights reserved.
+* Copyright (c) 2014, 2019, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 * @summary Exercise the java.lang.instrument.Instrumentation APIs on classes archived
 *          using CDS/AppCDSv1/AppCDSv2.
 * @library /test/lib /test/hotspot/jtreg/runtime/appcds /test/hotspot/jtreg/runtime/appcds/test-classes
 * @requires vm.cds
 * @requires vm.flavor != "minimal"
-* @modules java.base/jdk.internal.misc
-*          jdk.jartool/sun.tools.jar
-*          java.management
 * @build sun.hotspot.WhiteBox
 *        InstrumentationApp
 *        InstrumentationClassFileTransformer
 *        InstrumentationRegisterClassFileTransformer
 * @run main/othervm InstrumentationTest
 // Note: TestCommon is from /test/hotspot/jtreg/runtime/appcds/TestCommon.java
 // Note: Util       is from /test/hotspot/jtreg/runtime/appcds/test-classes/TestCommon.java
 import com.sun.tools.attach.VirtualMachine;
-import com.sun.tools.attach.VirtualMachineDescriptor;
 import java.io.File;
-import java.io.FileOutputStream;
+import java.io.FileInputStream;
-import java.util.List;
+import java.util.Scanner;
 import jdk.test.lib.Asserts;
 import jdk.test.lib.cds.CDSOptions;
 import jdk.test.lib.process.OutputAnalyzer;
 import jdk.test.lib.process.ProcessTools;
 static AgentAttachThread doAttach(boolean attachAgent, String flagFile, String agentJar) throws Throwable {
 if (!attachAgent) {
 return null;
 }
-// We use the flagFile to prevent the child process to make progress, until we have
+// Hand-shake protocol with the child process
-// attached to it.
+// [1] Parent process (this process) launches child process (InstrumentationApp)
+//     and then waits until child process writes its pid into the flagFile.
+// [2] Child process process starts up, writes its pid into the flagFile,
+//     and waits for the flagFile to be deleted.
+// [3] When parent process gets the pid, it attaches to the child process
+//     (if we attempt to attach to a process too early, the SIGQUIT
+//     may cause the child to die) and deletes the flagFile.
+// [4] Child process resumes execution.
 File f = new File(flagFile);
-try (FileOutputStream o = new FileOutputStream(f)) {
+f.delete();
-o.write(1);
+if (f.exists()) {
-}
+throw new RuntimeException("Flag file should not exist: " + f);
-if (!f.exists()) {
-throw new RuntimeException("Failed to create " + f);
 }
 // At this point, the child process is not yet launched. Note that
 // TestCommon.exec() and OutputAnalyzer.OutputAnalyzer() both block
 // until the child process has finished.
 //
-// So, we will launch a AgentAttachThread which will poll the system
+// So, we will launch a AgentAttachThread which will poll the flagFile
-// until the child process is launched, and then do the attachment.
+// until the child process is launched.
-// The child process is uniquely identified by having flagFile in its
-// command-line -- see AgentAttachThread.getPid().
 AgentAttachThread t = new AgentAttachThread(flagFile, agentJar);
 t.start();
 return t;
 }
 while (true) {
 // Keep polling until the child process has been launched. If for some
 // reason the child process fails to launch, this test will be terminated
 // by JTREG's time-out mechanism.
 Thread.sleep(100);
-List<VirtualMachineDescriptor> vmds = VirtualMachine.list();
+File f = new File(flagFile);
-for (VirtualMachineDescriptor vmd : vmds) {
+if (f.exists() && f.length() > 100) {
-if (vmd.displayName().contains(flagFile) && vmd.displayName().contains("InstrumentationApp")) {
+try (FileInputStream in = new FileInputStream(f)) {
-// We use flagFile (which has the PID of this process) as a unique identifier
+Scanner scanner = new Scanner(in);
-// to ident the child process, which we want to attach to.
+return Long.toString(scanner.nextLong());
-System.out.println("Process found: " + vmd.id() + " " + vmd.displayName());
+} catch (Throwable t) {
-return vmd.id();
+// This may happen on Windows if the child process has not
+// fully closed the output stream to the flagFile
+System.out.println("Ignored: " + t);
+t.printStackTrace(System.out);
+continue;
 }
 }
 }
 }
 public void run() {
 try {
 String pid = getPid(flagFile);
+System.out.println("child pid = " + pid);
 VirtualMachine vm = VirtualMachine.attach(pid);
 System.out.println(agentJar);
 vm.loadAgent(agentJar);
 } catch (Throwable t) {
 t.printStackTrace();

changeset 54297	f98f158c1db8
parent 52125	28375a1de254