1 /*
2 * Copyright (C) 2017, 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.reftable;
45
46 class ReftableConstants {
47 static final byte[] FILE_HEADER_MAGIC = { 'R', 'E', 'F', 'T' };
48 static final byte VERSION_1 = (byte) 1;
49
50 static final int FILE_HEADER_LEN = 24;
51 static final int FILE_FOOTER_LEN = 68;
52
53 static final byte FILE_BLOCK_TYPE = 'R';
54 static final byte REF_BLOCK_TYPE = 'r';
55 static final byte OBJ_BLOCK_TYPE = 'o';
56 static final byte LOG_BLOCK_TYPE = 'g';
57 static final byte INDEX_BLOCK_TYPE = 'i';
58
59 static final int VALUE_NONE = 0x0;
60 static final int VALUE_1ID = 0x1;
61 static final int VALUE_2ID = 0x2;
62 static final int VALUE_SYMREF = 0x3;
63 static final int VALUE_TYPE_MASK = 0x7;
64
65 static final int LOG_NONE = 0x0;
66 static final int LOG_DATA = 0x1;
67
68 static final int MAX_BLOCK_SIZE = (1 << 24) - 1;
69 static final int MAX_RESTARTS = 65535;
70
71 static boolean isFileHeaderMagic(byte[] buf, int o, int n) {
72 return (n - o) >= FILE_HEADER_MAGIC.length
73 && buf[o + 0] == FILE_HEADER_MAGIC[0]
74 && buf[o + 1] == FILE_HEADER_MAGIC[1]
75 && buf[o + 2] == FILE_HEADER_MAGIC[2]
76 && buf[o + 3] == FILE_HEADER_MAGIC[3];
77 }
78
79 static long reverseUpdateIndex(long time) {
80 return 0xffffffffffffffffL - time;
81 }
82
83 private ReftableConstants() {
84 }
85 }