1 /*
2 * Copyright (C) 2012, Robin Rosenberg
3 * Copyright (C) 2010, 2013 Marc Strapetz <marc.strapetz@syntevo.com>
4 * and other copyright owners as documented in the project's IP log.
5 *
6 * This program and the accompanying materials are made available
7 * under the terms of the Eclipse Distribution License v1.0 which
8 * accompanies this distribution, is reproduced below, and is
9 * available at http://www.eclipse.org/org/documents/edl-v10.php
10 *
11 * All rights reserved.
12 *
13 * Redistribution and use in source and binary forms, with or
14 * without modification, are permitted provided that the following
15 * conditions are met:
16 *
17 * - Redistributions of source code must retain the above copyright
18 * notice, this list of conditions and the following disclaimer.
19 *
20 * - Redistributions in binary form must reproduce the above
21 * copyright notice, this list of conditions and the following
22 * disclaimer in the documentation and/or other materials provided
23 * with the distribution.
24 *
25 * - Neither the name of the Eclipse Foundation, Inc. nor the
26 * names of its contributors may be used to endorse or promote
27 * products derived from this software without specific prior
28 * written permission.
29 *
30 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
31 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
32 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
33 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
34 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
35 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
36 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
37 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
38 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
39 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
41 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
42 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
43 */
44
45 package org.eclipse.jgit.util.io;
46
47 import java.io.IOException;
48 import java.io.InputStream;
49
50 import org.eclipse.jgit.diff.RawText;
51
52 /**
53 * An InputStream that expands LF to CRLF.
54 *
55 * Existing CRLF are not expanded to CRCRLF, but retained as is.
56 *
57 * Optionally, a binary check on the first 8000 bytes is performed and in case
58 * of binary files, canonicalization is turned off (for the complete file).
59 */
60 public class AutoCRLFInputStream extends InputStream {
61
62 static final int BUFFER_SIZE = 8096;
63
64 private final byte[] single = new byte[1];
65
66 private final byte[] buf = new byte[BUFFER_SIZE];
67
68 private final InputStream in;
69
70 private int cnt;
71
72 private int ptr;
73
74 private boolean isBinary;
75
76 private boolean detectBinary;
77
78 private byte last;
79
80 /**
81 * Creates a new InputStream, wrapping the specified stream
82 *
83 * @param in
84 * raw input stream
85 * @param detectBinary
86 * whether binaries should be detected
87 * @since 2.0
88 */
89 public AutoCRLFInputStream(InputStream in, boolean detectBinary) {
90 this.in = in;
91 this.detectBinary = detectBinary;
92 }
93
94 /** {@inheritDoc} */
95 @Override
96 public int read() throws IOException {
97 final int read = read(single, 0, 1);
98 return read == 1 ? single[0] & 0xff : -1;
99 }
100
101 /** {@inheritDoc} */
102 @Override
103 public int read(byte[] bs, int off, int len) throws IOException {
104 if (len == 0)
105 return 0;
106
107 if (cnt == -1)
108 return -1;
109
110 int i = off;
111 final int end = off + len;
112
113 while (i < end) {
114 if (ptr == cnt && !fillBuffer())
115 break;
116
117 byte b = buf[ptr++];
118 if (isBinary || b != '\n') {
119 // Logic for binary files ends here
120 bs[i++] = last = b;
121 continue;
122 }
123
124 if (b == '\n') {
125 if (last == '\r') {
126 bs[i++] = last = b;
127 continue;
128 }
129 bs[i++] = last = '\r';
130 ptr--;
131 } else
132 bs[i++] = last = b;
133 }
134 int n = i == off ? -1 : i - off;
135 if (n > 0)
136 last = bs[i - 1];
137 return n;
138 }
139
140 /** {@inheritDoc} */
141 @Override
142 public void close() throws IOException {
143 in.close();
144 }
145
146 private boolean fillBuffer() throws IOException {
147 cnt = in.read(buf, 0, buf.length);
148 if (cnt < 1)
149 return false;
150 if (detectBinary) {
151 isBinary = RawText.isBinary(buf, cnt);
152 detectBinary = false;
153 }
154 ptr = 0;
155 return true;
156 }
157 }