Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright (c) 2013, 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.

  *

  * This code is distributed in the hope that it will be useful, but WITHOUT

  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

  * version 2 for more details (a copy is included in the LICENSE file that

  * accompanied this code).

  *

  * You should have received a copy of the GNU General Public License version

  * 2 along with this work; if not, write to the Free Software Foundation,

  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

  *

  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

  * or visit www.oracle.com if you need additional information or have any

  * questions.

  */

 /*

  * @test

  * @bug 7162400

  * @key regression

  * @summary Regression test for attach issue where stale pid files in /tmp lead to connection issues

  * @library /testlibrary

  * @build com.oracle.java.testlibrary.* AttachWithStalePidFileTarget

  * @run main AttachWithStalePidFile

  */

 import com.oracle.java.testlibrary.*;

 import com.sun.tools.attach.VirtualMachine;

 import sun.tools.attach.HotSpotVirtualMachine;

 import java.lang.reflect.Field;

 import java.nio.file.*;

 import java.nio.file.attribute.*;

 import java.io.*;

 public class AttachWithStalePidFile {

   public static void main(String... args) throws Exception {

     // this test is only valid on non-Windows platforms

     if(Platform.isWindows()) {

       System.out.println("This test is only valid on non-Windows platforms.");

       return;

     }

     // Since there might be stale pid-files owned by different

     // users on the system we may need to retry the test in case we

     // are unable to remove the existing file.

     int retries = 5;

     while(!runTest() && --retries > 0);

     if(retries == 0) {

       throw new RuntimeException("Test failed after 5 retries. " +

         "Remove any /tmp/.java_pid* files and retry.");

     }

   }

   public static boolean runTest() throws Exception {

     ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(

       "-XX:+UnlockDiagnosticVMOptions", "-XX:+PauseAtStartup", "AttachWithStalePidFileTarget");

     Process target = pb.start();

     Path pidFile = null;

     try {

       int pid = getUnixProcessId(target);

       // create the stale .java_pid file. use hard-coded /tmp path as in th VM

       pidFile = createJavaPidFile(pid);

       if(pidFile == null) {

         return false;

       }

       // wait for vm.paused file to be created and delete it once we find it.

       waitForAndResumeVM(pid);

       // unfortunately there's no reliable way to know the VM is ready to receive the

       // attach request so we have to do an arbitrary sleep.

       Thread.sleep(5000);

       HotSpotVirtualMachine vm = (HotSpotVirtualMachine)VirtualMachine.attach(((Integer)pid).toString());

       BufferedReader remoteDataReader = new BufferedReader(new InputStreamReader(vm.remoteDataDump()));

       String line = null;

       while((line = remoteDataReader.readLine()) != null);

       vm.detach();

       return true;

     }

     finally {

       target.destroy();

       target.waitFor();

       if(pidFile != null && Files.exists(pidFile)) {

         Files.delete(pidFile);

       }

     }

   }

   private static Path createJavaPidFile(int pid) throws Exception {

     Path pidFile = Paths.get("/tmp/.java_pid" + pid);

     if(Files.exists(pidFile)) {

       try {

         Files.delete(pidFile);

       }

       catch(FileSystemException e) {

         if(e.getReason().equals("Operation not permitted")) {

           System.out.println("Unable to remove exisiting stale PID file" + pidFile);

           return null;

         }

         throw e;

       }

     }

     return Files.createFile(pidFile,

       PosixFilePermissions.asFileAttribute(PosixFilePermissions.fromString("rw-------")));

   }

   private static void waitForAndResumeVM(int pid) throws Exception {

     Path pauseFile = Paths.get("vm.paused." + pid);

     int retries = 60;

     while(!Files.exists(pauseFile) && --retries > 0) {

       Thread.sleep(1000);

     }

     if(retries == 0) {

       throw new RuntimeException("Timeout waiting for VM to start. " +

         "vm.paused file not created within 60 seconds.");

     }

     Files.delete(pauseFile);

   }

   private static int getUnixProcessId(Process unixProcess) throws Exception {

     Field pidField = unixProcess.getClass().getDeclaredField("pid");

     pidField.setAccessible(true);

     return (Integer)pidField.get(unixProcess);

   }

 }