test/lib/jdk/test/lib/util/FileUtils.java

rev 50699 : 8202292: java/io/FileOutputStream/UnreferencedFOSClosesFd.java fails with "raw fd count wrong"

*** 1,7 ****
  /*
!  * Copyright (c) 2017, 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.
--- 1,7 ----
  /*
!  * Copyright (c) 2017, 2018, 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.
*** 24,45 ****
  package jdk.test.lib.util;
  
  import jdk.test.lib.Platform;
  
  import java.io.IOException;
  import java.nio.file.DirectoryNotEmptyException;
  import java.nio.file.FileVisitResult;
  import java.nio.file.Files;
  import java.nio.file.NoSuchFileException;
  import java.nio.file.Path;
  import java.nio.file.SimpleFileVisitor;
  import java.nio.file.attribute.BasicFileAttributes;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.concurrent.TimeUnit;
  
- 
  /**
   * Common library for various test file utility functions.
   */
  public final class FileUtils {
      private static final boolean IS_WINDOWS = Platform.isWindows();
--- 24,53 ----
  package jdk.test.lib.util;
  
  import jdk.test.lib.Platform;
  
  import java.io.IOException;
+ import java.io.PrintStream;
+ import java.io.UncheckedIOException;
+ import java.lang.ProcessBuilder.Redirect;
  import java.nio.file.DirectoryNotEmptyException;
  import java.nio.file.FileVisitResult;
  import java.nio.file.Files;
  import java.nio.file.NoSuchFileException;
  import java.nio.file.Path;
+ import java.nio.file.Paths;
  import java.nio.file.SimpleFileVisitor;
  import java.nio.file.attribute.BasicFileAttributes;
+ import java.time.Instant;
+ import java.time.Duration;
  import java.util.ArrayList;
+ import java.util.ArrayDeque;
+ import java.util.HashSet;
  import java.util.List;
+ import java.util.Optional;
  import java.util.concurrent.TimeUnit;
  
  /**
   * Common library for various test file utility functions.
   */
  public final class FileUtils {
      private static final boolean IS_WINDOWS = Platform.isWindows();
*** 225,230 ****
--- 233,276 ----
                  areFileSystemsAccessible = false;
              }
          }
          return areFileSystemsAccessible;
      }
+ 
+     /**
+      * List the open file descriptors (if supported by the 'lsof' command).
+      * @param ps a printStream to send the output to
+      * @throws UncheckedIOException if an error occurs
+      */
+     public static void listFileDescriptors(PrintStream ps) {
+         List<String> lsofDirs = List.of("/usr/bin", "/usr/sbin");
+         Optional<Path> lsof = lsofDirs.stream()
+                 .map(s -> Paths.get(s, "lsof"))
+                 .filter(f -> Files.isExecutable(f))
+                 .findFirst();
+         lsof.ifPresent(exe -> {
+             try {
+                 ps.printf("Open File Descriptors:%n");
+                 long pid = ProcessHandle.current().pid();
+                 ProcessBuilder pb = new ProcessBuilder(exe.toString(), "-p", Integer.toString((int) pid));
+                 pb.redirectErrorStream(true);   // combine stderr and stdout
+                 pb.redirectOutput(Redirect.PIPE);
+ 
+                 Process p = pb.start();
+                 Instant start = Instant.now();
+                 p.getInputStream().transferTo(ps);
+ 
+                 try {
+                     int timeout = 10;
+                     if (!p.waitFor(timeout, TimeUnit.SECONDS)) {
+                         System.out.printf("waitFor timed out: %d%n", timeout);
+                     }
+                 } catch (InterruptedException ie) {
+                     throw new IOException("interrupted", ie);
+                 }
+                 ps.println();
+             } catch (IOException ioe) {
+                 throw new UncheckedIOException("error listing file descriptors", ioe);
+             }
+         });
+     }
  }