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1   /*
2    * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
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.file;
45  
46  import java.io.IOException;
47  import java.io.OutputStream;
48  
49  import org.eclipse.jgit.transport.PackedObjectInfo;
50  import org.eclipse.jgit.util.NB;
51  
52  /**
53   * Creates the version 2 pack table of contents files.
54   *
55   * @see PackIndexWriter
56   * @see PackIndexV2
57   */
58  class PackIndexWriterV2 extends PackIndexWriter {
59  	private static final int MAX_OFFSET_32 = 0x7fffffff;
60  	private static final int IS_OFFSET_64 = 0x80000000;
61  
62  	PackIndexWriterV2(final OutputStream dst) {
63  		super(dst);
64  	}
65  
66  	/** {@inheritDoc} */
67  	@Override
68  	protected void writeImpl() throws IOException {
69  		writeTOC(2);
70  		writeFanOutTable();
71  		writeObjectNames();
72  		writeCRCs();
73  		writeOffset32();
74  		writeOffset64();
75  		writeChecksumFooter();
76  	}
77  
78  	private void writeObjectNames() throws IOException {
79  		for (PackedObjectInfo oe : entries)
80  			oe.copyRawTo(out);
81  	}
82  
83  	private void writeCRCs() throws IOException {
84  		for (PackedObjectInfo oe : entries) {
85  			NB.encodeInt32(tmp, 0, oe.getCRC());
86  			out.write(tmp, 0, 4);
87  		}
88  	}
89  
90  	private void writeOffset32() throws IOException {
91  		int o64 = 0;
92  		for (PackedObjectInfo oe : entries) {
93  			final long o = oe.getOffset();
94  			if (o <= MAX_OFFSET_32)
95  				NB.encodeInt32(tmp, 0, (int) o);
96  			else
97  				NB.encodeInt32(tmp, 0, IS_OFFSET_64 | o64++);
98  			out.write(tmp, 0, 4);
99  		}
100 	}
101 
102 	private void writeOffset64() throws IOException {
103 		for (PackedObjectInfo oe : entries) {
104 			final long o = oe.getOffset();
105 			if (MAX_OFFSET_32 < o) {
106 				NB.encodeInt64(tmp, 0, o);
107 				out.write(tmp, 0, 8);
108 			}
109 		}
110 	}
111 }