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 import static java.lang.Long.parseLong; 25 import static java.lang.System.getProperty; 26 import static java.nio.file.Files.readAllBytes; 27 import static java.util.Arrays.stream; 28 import static java.util.stream.Collectors.joining; 29 import static java.util.stream.Collectors.toList; 30 import static jdk.test.lib.process.ProcessTools.createJavaProcessBuilder; 31 import static jdk.test.lib.Platform.isWindows; 32 import jdk.test.lib.Utils; 33 import jtreg.SkippedException; 34 35 import java.io.BufferedReader; 36 import java.io.File; 37 import java.io.FileNotFoundException; 38 import java.io.FileOutputStream; 39 import java.io.IOException; 40 import java.io.InputStreamReader; 41 import java.util.Collection; 42 import java.util.Optional; 43 import java.util.stream.Stream; 44 45 /* 46 * @test TestInheritFD 47 * @bug 8176717 8176809 8222500 48 * @summary a new process should not inherit open file descriptors 49 * @comment On Aix lsof requires root privileges. 50 * @requires os.family != "aix" 51 * @library /test/lib 52 * @modules java.base/jdk.internal.misc 53 * java.management 54 * @run driver TestInheritFD 55 */ 56 57 /** 58 * Test that HotSpot does not leak logging file descriptors. 59 * 60 * This test is performed in three steps. The first VM starts a second VM with 61 * gc logging enabled. The second VM starts a third VM and redirects the third 62 * VMs output to the first VM, it then exits and hopefully closes its log file. 63 * 64 * The third VM waits for the second to exit and close its log file. After that, 65 * the third VM tries to rename the log file of the second VM. If it succeeds in 66 * doing so it means that the third VM did not inherit the open log file 67 * (windows can not rename opened files easily) 68 * 69 * The third VM communicates the success to rename the file by printing "CLOSED 70 * FD". The first VM checks that the string was printed by the third VM. 71 * 72 * On unix like systems "lsof" is used. 73 */ 74 75 public class TestInheritFD { 76 77 public static final String LEAKS_FD = "VM RESULT => LEAKS FD"; 78 public static final String RETAINS_FD = "VM RESULT => RETAINS FD"; 79 public static final String EXIT = "VM RESULT => VM EXIT"; 80 public static final String LOG_SUFFIX = ".strangelogsuffixthatcanbecheckedfor"; 81 82 // first VM 83 public static void main(String[] args) throws Exception { 84 String logPath = Utils.createTempFile("logging", LOG_SUFFIX).toFile().getName(); 85 File commFile = Utils.createTempFile("communication", ".txt").toFile(); 86 87 if (!isWindows() && !lsofCommand().isPresent()) { 88 throw new SkippedException("Could not find lsof like command"); 89 } 90 91 ProcessBuilder pb = createJavaProcessBuilder( 92 "-Xlog:gc:\"" + logPath + "\"", 93 "-Dtest.jdk=" + getProperty("test.jdk"), 94 VMStartedWithLogging.class.getName(), 95 logPath); 96 97 pb.redirectOutput(commFile); // use temp file to communicate between processes 98 pb.start(); 99 100 String out = ""; 101 do { 102 out = new String(readAllBytes(commFile.toPath())); 103 Thread.sleep(100); 104 System.out.println("SLEEP 100 millis"); 105 } while (!out.contains(EXIT)); 106 107 System.out.println(out); 108 if (out.contains(RETAINS_FD)) { 109 System.out.println("Log file was not inherited by third VM"); 110 } else { 111 throw new RuntimeException("could not match: " + RETAINS_FD); 112 } 113 } 114 115 static class VMStartedWithLogging { 116 // second VM 117 public static void main(String[] args) throws IOException, InterruptedException { 118 ProcessBuilder pb = createJavaProcessBuilder( 119 "-Dtest.jdk=" + getProperty("test.jdk"), 120 VMShouldNotInheritFileDescriptors.class.getName(), 121 args[0], 122 "" + ProcessHandle.current().pid()); 123 pb.inheritIO(); // in future, redirect information from third VM to first VM 124 pb.start(); 125 126 if (!isWindows()) { 127 System.out.println("(Second VM) Open file descriptors:\n" + outputContainingFilenames().stream().collect(joining("\n"))); 128 } 129 } 130 } 131 132 static class VMShouldNotInheritFileDescriptors { 133 // third VM 134 public static void main(String[] args) throws InterruptedException { 135 try { 136 File logFile = new File(args[0]); 137 long parentPid = parseLong(args[1]); 138 fakeLeakyJVM(false); // for debugging of test case 139 140 if (isWindows()) { 141 windows(logFile, parentPid); 142 } else { 143 Collection<String> output = outputContainingFilenames(); 144 System.out.println("(Third VM) Open file descriptors:\n" + output.stream().collect(joining("\n"))); 145 System.out.println(findOpenLogFile(output) ? LEAKS_FD : RETAINS_FD); 146 } 147 } catch (Exception e) { 148 System.out.println(e.toString()); 149 } finally { 150 System.out.println(EXIT); 151 } 152 } 153 } 154 155 // for debugging of test case 156 @SuppressWarnings("resource") 157 static void fakeLeakyJVM(boolean fake) { 158 if (fake) { 159 try { 160 new FileOutputStream("fakeLeakyJVM" + LOG_SUFFIX, false); 161 } catch (FileNotFoundException e) { 162 } 163 } 164 } 165 166 static Stream<String> run(String... args){ 167 try { 168 return new BufferedReader(new InputStreamReader(new ProcessBuilder(args).start().getInputStream())).lines(); 169 } catch (IOException e) { 170 throw new RuntimeException(e); 171 } 172 } 173 174 static Optional<String[]> lsofCommandCache = stream(new String[][]{ 175 {"/usr/bin/lsof", "-p"}, 176 {"/usr/sbin/lsof", "-p"}, 177 {"/bin/lsof", "-p"}, 178 {"/sbin/lsof", "-p"}, 179 {"/usr/local/bin/lsof", "-p"}}) 180 .filter(args -> new File(args[0]).exists()) 181 .findFirst(); 182 183 static Optional<String[]> lsofCommand() { 184 return lsofCommandCache; 185 } 186 187 static Collection<String> outputContainingFilenames() { 188 long pid = ProcessHandle.current().pid(); 189 190 String[] command = lsofCommand().orElseThrow(() -> new RuntimeException("lsof like command not found")); 191 System.out.println("using command: " + command[0] + " " + command[1]); 192 return run(command[0], command[1], "" + pid).collect(toList()); 193 } 194 195 static boolean findOpenLogFile(Collection<String> fileNames) { 196 return fileNames.stream() 197 .filter(fileName -> fileName.contains(LOG_SUFFIX)) 198 .findAny() 199 .isPresent(); 200 } 201 202 static void windows(File f, long parentPid) throws InterruptedException { 203 System.out.println("waiting for pid: " + parentPid); 204 ProcessHandle.of(parentPid).ifPresent(handle -> handle.onExit().join()); 205 System.out.println("trying to rename file to the same name: " + f); 206 System.out.println(f.renameTo(f) ? RETAINS_FD : LEAKS_FD); // this parts communicates a closed file descriptor by printing "VM RESULT => RETAINS FD" 207 } 208 } 209