1 /*
2 * Copyright (C) 2016, Google Inc.
3 * and other copyright owners as documented in the project's IP log.
4 *
5 * This program and the accompanying materials are made available
6 * under the terms of the Eclipse Distribution License v1.0 which
7 * accompanies this distribution, is reproduced below, and is
8 * available at http://www.eclipse.org/org/documents/edl-v10.php
9 *
10 * All rights reserved.
11 *
12 * Redistribution and use in source and binary forms, with or
13 * without modification, are permitted provided that the following
14 * conditions are met:
15 *
16 * - Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 *
19 * - Redistributions in binary form must reproduce the above
20 * copyright notice, this list of conditions and the following
21 * disclaimer in the documentation and/or other materials provided
22 * with the distribution.
23 *
24 * - Neither the name of the Eclipse Foundation, Inc. nor the
25 * names of its contributors may be used to endorse or promote
26 * products derived from this software without specific prior
27 * written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
30 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
31 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
34 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
35 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
36 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
37 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
38 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
40 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
41 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
42 */
43
44 package org.eclipse.jgit.internal.storage.reftree;
45
46 import org.eclipse.jgit.lib.RefDatabase;
47
48 /** Magic reference name logic for RefTrees. */
49 public class RefTreeNames {
50 /**
51 * Suffix used on a {@link RefTreeDatabase#getTxnNamespace()} for user data.
52 * <p>
53 * A {@link RefTreeDatabase}'s namespace may include a subspace (e.g.
54 * {@code "refs/txn/stage/"}) containing commit objects from the usual user
55 * portion of the repository (e.g. {@code "refs/heads/"}). These should be
56 * packed by the garbage collector alongside other user content rather than
57 * with the RefTree.
58 */
59 private static final String STAGE = "stage/"; //$NON-NLS-1$
60
61 /**
62 * Determine if the reference is likely to be a RefTree.
63 *
64 * @param refdb
65 * database instance.
66 * @param ref
67 * reference name.
68 * @return {@code true} if the reference is a RefTree.
69 */
70 public static boolean isRefTree(RefDatabase refdb, String ref) {
71 if (refdb instanceof RefTreeDatabase) {
72 RefTreeDatabase b = (RefTreeDatabase) refdb;
73 if (ref.equals(b.getTxnCommitted())) {
74 return true;
75 }
76
77 String namespace = b.getTxnNamespace();
78 if (namespace != null
79 && ref.startsWith(namespace)
80 && !ref.startsWith(namespace + STAGE)) {
81 return true;
82 }
83 }
84 return false;
85 }
86
87 private RefTreeNames() {
88 }
89 }