1 /* 2 * Copyright (c) 2013, 2016, 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 * @test 26 * @bug 7162400 27 * @key regression 28 * @summary Regression test for attach issue where stale pid files in /tmp lead to connection issues 29 * @modules java.base/jdk.internal.misc:open 30 * @modules java.base/java.lang:open 31 * @modules jdk.attach/sun.tools.attach 32 * @library /test/lib 33 * @run main AttachWithStalePidFile 34 */ 35 36 import jdk.test.lib.Platform; 37 import jdk.test.lib.process.ProcessTools; 38 import com.sun.tools.attach.VirtualMachine; 39 import sun.tools.attach.HotSpotVirtualMachine; 40 import java.lang.reflect.Field; 41 import java.nio.file.*; 42 import java.nio.file.attribute.*; 43 import java.io.*; 44 45 public class AttachWithStalePidFile { main(String... args)46 public static void main(String... args) throws Exception { 47 48 // this test is only valid on non-Windows platforms 49 if(Platform.isWindows()) { 50 System.out.println("This test is only valid on non-Windows platforms."); 51 return; 52 } 53 54 // Since there might be stale pid-files owned by different 55 // users on the system we may need to retry the test in case we 56 // are unable to remove the existing file. 57 int retries = 5; 58 while(!runTest() && --retries > 0); 59 60 if(retries == 0) { 61 throw new RuntimeException("Test failed after 5 retries. " + 62 "Remove any /tmp/.java_pid* files and retry."); 63 } 64 } 65 runTest()66 public static boolean runTest() throws Exception { 67 ProcessBuilder pb = ProcessTools.createJavaProcessBuilder( 68 "-XX:+UnlockDiagnosticVMOptions", "-XX:+PauseAtStartup", "AttachWithStalePidFileTarget"); 69 Process target = pb.start(); 70 Path pidFile = null; 71 72 try { 73 int pid = getUnixProcessId(target); 74 75 // create the stale .java_pid file. use hard-coded /tmp path as in th VM 76 pidFile = createJavaPidFile(pid); 77 if(pidFile == null) { 78 return false; 79 } 80 81 // wait for vm.paused file to be created and delete it once we find it. 82 waitForAndResumeVM(pid); 83 84 waitForTargetReady(target); 85 86 HotSpotVirtualMachine vm = (HotSpotVirtualMachine)VirtualMachine.attach(((Integer)pid).toString()); 87 BufferedReader remoteDataReader = new BufferedReader(new InputStreamReader(vm.remoteDataDump())); 88 String line = null; 89 while((line = remoteDataReader.readLine()) != null); 90 91 vm.detach(); 92 return true; 93 } 94 finally { 95 target.destroy(); 96 target.waitFor(); 97 98 if(pidFile != null && Files.exists(pidFile)) { 99 Files.delete(pidFile); 100 } 101 } 102 } 103 waitForTargetReady(Process target)104 private static void waitForTargetReady(Process target) throws IOException { 105 BufferedReader br = new BufferedReader(new InputStreamReader(target.getInputStream())); 106 String line = br.readLine(); 107 // wait for the ready message having been printed or EOF (line == null) 108 while (line != null && !line.equals(AttachWithStalePidFileTarget.READY_MSG)) { 109 line = br.readLine(); 110 } 111 // target VM ready 112 } 113 createJavaPidFile(int pid)114 private static Path createJavaPidFile(int pid) throws Exception { 115 Path pidFile = Paths.get("/tmp/.java_pid" + pid); 116 if(Files.exists(pidFile)) { 117 try { 118 Files.delete(pidFile); 119 } 120 catch(FileSystemException e) { 121 if(e.getReason().matches("Operation not permitted|Not owner")) { 122 System.out.println("Unable to remove exisiting stale PID file" + pidFile); 123 System.out.println("==================================================="); 124 e.printStackTrace(System.out); 125 return null; 126 } 127 throw e; 128 } 129 } 130 return Files.createFile(pidFile, 131 PosixFilePermissions.asFileAttribute(PosixFilePermissions.fromString("rw-------"))); 132 } 133 waitForAndResumeVM(int pid)134 private static void waitForAndResumeVM(int pid) throws Exception { 135 Path pauseFile = Paths.get("vm.paused." + pid); 136 int retries = 60; 137 while(!Files.exists(pauseFile) && --retries > 0) { 138 Thread.sleep(1000); 139 } 140 if(retries == 0) { 141 throw new RuntimeException("Timeout waiting for VM to start. " + 142 "vm.paused file not created within 60 seconds."); 143 } 144 Files.delete(pauseFile); 145 } 146 getUnixProcessId(Process unixProcess)147 private static int getUnixProcessId(Process unixProcess) throws Exception { 148 Field pidField = unixProcess.getClass().getDeclaredField("pid"); 149 pidField.setAccessible(true); 150 return (Integer)pidField.get(unixProcess); 151 } 152 } 153