1 /*
2 * Copyright (C) 2009, Google Inc. and others
3 *
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Distribution License v. 1.0 which is available at
6 * https://www.eclipse.org/org/documents/edl-v10.php.
7 *
8 * SPDX-License-Identifier: BSD-3-Clause
9 */
10
11 package org.eclipse.jgit.internal.storage.file;
12
13 import java.io.File;
14 import java.io.IOException;
15
16 import org.eclipse.jgit.lib.Constants;
17 import org.eclipse.jgit.util.FS;
18 import org.eclipse.jgit.util.FileUtils;
19
20 /**
21 * Keeps track of a {@link org.eclipse.jgit.internal.storage.file.PackFile}'s
22 * associated <code>.keep</code> file.
23 */
24 public class PackLock {
25 private final File keepFile;
26
27 /**
28 * Create a new lock for a pack file.
29 *
30 * @param packFile
31 * location of the <code>pack-*.pack</code> file.
32 * @param fs
33 * the filesystem abstraction used by the repository.
34 */
35 public PackLock(File packFile, FS fs) {
36 final File p = packFile.getParentFile();
37 final String n = packFile.getName();
38 keepFile = new File(p, n.substring(0, n.length() - 5) + ".keep"); //$NON-NLS-1$
39 }
40
41 /**
42 * Create the <code>pack-*.keep</code> file, with the given message.
43 *
44 * @param msg
45 * message to store in the file.
46 * @return true if the keep file was successfully written; false otherwise.
47 * @throws java.io.IOException
48 * the keep file could not be written.
49 */
50 public boolean lock(String msg) throws IOException {
51 if (msg == null)
52 return false;
53 if (!msg.endsWith("\n")) //$NON-NLS-1$
54 msg += "\n"; //$NON-NLS-1$
55 final LockFileernal/storage/file/LockFile.html#LockFile">LockFile lf = new LockFile(keepFile);
56 if (!lf.lock())
57 return false;
58 lf.write(Constants.encode(msg));
59 return lf.commit();
60 }
61
62 /**
63 * Remove the <code>.keep</code> file that holds this pack in place.
64 *
65 * @throws java.io.IOException
66 * if deletion of .keep file failed
67 */
68 public void unlock() throws IOException {
69 FileUtils.delete(keepFile);
70 }
71 }