1 /*

     2  * Copyright (c) 2017, 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 package jdk.testlibrary;

    25 

    26 import java.io.IOException;

    27 import java.nio.file.DirectoryNotEmptyException;

    28 import java.nio.file.FileVisitResult;

    29 import java.nio.file.Files;

    30 import java.nio.file.NoSuchFileException;

    31 import java.nio.file.Path;

    32 import java.nio.file.SimpleFileVisitor;

    33 import java.nio.file.attribute.BasicFileAttributes;

    34 import java.util.ArrayList;

    35 import java.util.List;

    36 import java.util.concurrent.TimeUnit;

    37 

    38 

    39 /**

    40  * Common library for various test file utility functions.

    41  */

    42 public final class FileUtils {

    43 

    44     private static final boolean isWindows =

    45                             System.getProperty("os.name").startsWith("Windows");

    46     private static final int RETRY_DELETE_MILLIS = isWindows ? 500 : 0;

    47     private static final int MAX_RETRY_DELETE_TIMES = isWindows ? 15 : 0;

    48 

    49     /**

    50      * Deletes a file, retrying if necessary.

    51      *

    52      * @param path  the file to delete

    53      *

    54      * @throws NoSuchFileException

    55      *         if the file does not exist (optional specific exception)

    56      * @throws DirectoryNotEmptyException

    57      *         if the file is a directory and could not otherwise be deleted

    58      *         because the directory is not empty (optional specific exception)

    59      * @throws IOException

    60      *         if an I/O error occurs

    61      */

    62     public static void deleteFileWithRetry(Path path)

    63         throws IOException

    64     {

    65         try {

    66             deleteFileWithRetry0(path);

    67         } catch (InterruptedException x) {

    68             throw new IOException("Interrupted while deleting.", x);

    69         }

    70     }

    71 

    72     /**

    73      * Deletes a file, retrying if necessary.

    74      * No exception thrown if file doesn't exist.

    75      *

    76      * @param path  the file to delete

    77      *

    78      * @throws NoSuchFileException

    79      *         if the file does not exist (optional specific exception)

    80      * @throws DirectoryNotEmptyException

    81      *         if the file is a directory and could not otherwise be deleted

    82      *         because the directory is not empty (optional specific exception)

    83      * @throws IOException

    84      *         if an I/O error occurs

    85      */

    86     public static void deleteFileIfExistsWithRetry(Path path)

    87         throws IOException

    88     {

    89         try {

    90             if(Files.exists(path))

    91                 deleteFileWithRetry0(path);

    92         } catch (InterruptedException x) {

    93             throw new IOException("Interrupted while deleting.", x);

    94         }

    95     }

    96 

    97     private static void deleteFileWithRetry0(Path path)

    98         throws IOException, InterruptedException

    99     {

   100         int times = 0;

   101         IOException ioe = null;

   102         while (true) {

   103             try {

   104                 Files.delete(path);

   105                 while (Files.exists(path)) {

   106                     times++;

   107                     if (times > MAX_RETRY_DELETE_TIMES)

   108                         throw new IOException("File still exists after " + times + " waits.");

   109                     Thread.sleep(RETRY_DELETE_MILLIS);

   110                 }

   111                 break;

   112             } catch (NoSuchFileException | DirectoryNotEmptyException x) {

   113                 throw x;

   114             } catch (IOException x) {

   115                 // Backoff/retry in case another process is accessing the file

   116                 times++;

   117                 if (ioe == null)

   118                     ioe = x;

   119                 else

   120                     ioe.addSuppressed(x);

   121 

   122                 if (times > MAX_RETRY_DELETE_TIMES)

   123                     throw ioe;

   124                 Thread.sleep(RETRY_DELETE_MILLIS);

   125             }

   126         }

   127     }

   128 

   129     /**

   130      * Deletes a directory and its subdirectories, retrying if necessary.

   131      *

   132      * @param dir  the directory to delete

   133      *

   134      * @throws  IOException

   135      *          If an I/O error occurs. Any such exceptions are caught

   136      *          internally. If only one is caught, then it is re-thrown.

   137      *          If more than one exception is caught, then the second and

   138      *          following exceptions are added as suppressed exceptions of the

   139      *          first one caught, which is then re-thrown.

   140      */

   141     public static void deleteFileTreeWithRetry(Path dir)

   142          throws IOException

   143     {

   144         IOException ioe = null;

   145         final List<IOException> excs = deleteFileTreeUnchecked(dir);

   146         if (!excs.isEmpty()) {

   147             ioe = excs.remove(0);

   148             for (IOException x : excs)

   149                 ioe.addSuppressed(x);

   150         }

   151         if (ioe != null)

   152             throw ioe;

   153     }

   154 

   155     public static List<IOException> deleteFileTreeUnchecked(Path dir) {

   156         final List<IOException> excs = new ArrayList<>();

   157         try {

   158             java.nio.file.Files.walkFileTree(dir, new SimpleFileVisitor<Path>() {

   159                 @Override

   160                 public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) {

   161                     try {

   162                         deleteFileWithRetry0(file);

   163                     } catch (IOException x) {

   164                         excs.add(x);

   165                     } catch (InterruptedException x) {

   166                         excs.add(new IOException("Interrupted while deleting.", x));

   167                         return FileVisitResult.TERMINATE;

   168                     }

   169                     return FileVisitResult.CONTINUE;

   170                 }

   171                 @Override

   172                 public FileVisitResult postVisitDirectory(Path dir, IOException exc) {

   173                     try {

   174                         deleteFileWithRetry0(dir);

   175                     } catch (IOException x) {

   176                         excs.add(x);

   177                     } catch (InterruptedException x) {

   178                         excs.add(new IOException("Interrupted while deleting.", x));

   179                         return FileVisitResult.TERMINATE;

   180                     }

   181                     return FileVisitResult.CONTINUE;

   182                 }

   183                 @Override

   184                 public FileVisitResult visitFileFailed(Path file, IOException exc) {

   185                     excs.add(exc);

   186                     return FileVisitResult.CONTINUE;

   187                 }

   188             });

   189         } catch (IOException x) {

   190             excs.add(x);

   191         }

   192         return excs;

   193     }

   194 

   195     /**

   196      * Checks whether all file systems are accessible. This is performed

   197      * by checking free disk space on all mounted file systems via a

   198      * separate, spawned process. File systems are considered to be

   199      * accessible if this process completes successfully before a given

   200      * fixed duration has elapsed.

   201      *

   202      * @implNote On Unix this executes the {@code df} command in a separate

   203      * process and on Windows always returns {@code true}.

   204      */

   205     public static boolean areFileSystemsAccessible() throws IOException {

   206         boolean areFileSystemsAccessible = true;

   207         if (!isWindows) {

   208             // try to check whether 'df' hangs

   209             System.out.println("\n--- df output ---");

   210             System.out.flush();

   211             Process proc = new ProcessBuilder("df").inheritIO().start();

   212             try {

   213                 proc.waitFor(90, TimeUnit.SECONDS);

   214             } catch (InterruptedException ignored) {

   215             }

   216             try {

   217                 int exitValue = proc.exitValue();

   218                 if (exitValue != 0) {

   219                     System.err.printf("df process exited with %d != 0%n",

   220                         exitValue);

   221                     areFileSystemsAccessible = false;

   222                 }

   223             } catch (IllegalThreadStateException ignored) {

   224                 System.err.println("df command apparently hung");

   225                 areFileSystemsAccessible = false;

   226             }

   227         }

   228         return areFileSystemsAccessible;

   229     }

   230 }