xref: /freebsd/usr.bin/gzip/unbzip2.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
1 /*	$NetBSD: unbzip2.c,v 1.14 2017/08/04 07:27:08 mrg Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-2-Clause
5  *
6  * Copyright (c) 2006 The NetBSD Foundation, Inc.
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to The NetBSD Foundation
10  * by Simon Burge.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
23  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
25  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 /* This file is #included by gzip.c */
35 
36 static off_t
37 unbzip2(int in, int out, char *pre, size_t prelen, off_t *bytes_in)
38 {
39 	int		ret, end_of_file, cold = 0;
40 	off_t		bytes_out = 0;
41 	bz_stream	bzs;
42 	static char	*inbuf, *outbuf;
43 
44 	if (inbuf == NULL)
45 		inbuf = malloc(BUFLEN);
46 	if (outbuf == NULL)
47 		outbuf = malloc(BUFLEN);
48 	if (inbuf == NULL || outbuf == NULL)
49 	        maybe_err("malloc");
50 
51 	bzs.bzalloc = NULL;
52 	bzs.bzfree = NULL;
53 	bzs.opaque = NULL;
54 
55 	end_of_file = 0;
56 	ret = BZ2_bzDecompressInit(&bzs, 0, 0);
57 	if (ret != BZ_OK)
58 	        maybe_errx("bzip2 init");
59 
60 	/* Prepend. */
61 	bzs.avail_in = prelen;
62 	bzs.next_in = pre;
63 
64 	if (bytes_in)
65 		*bytes_in = prelen;
66 
67 	while (ret == BZ_OK) {
68 		check_siginfo();
69 	        if (bzs.avail_in == 0 && !end_of_file) {
70 			ssize_t	n;
71 
72 	                n = read(in, inbuf, BUFLEN);
73 	                if (n < 0)
74 	                        maybe_err("read");
75 	                if (n == 0)
76 	                        end_of_file = 1;
77 			infile_newdata(n);
78 	                bzs.next_in = inbuf;
79 	                bzs.avail_in = n;
80 			if (bytes_in)
81 				*bytes_in += n;
82 	        }
83 
84 	        bzs.next_out = outbuf;
85 	        bzs.avail_out = BUFLEN;
86 	        ret = BZ2_bzDecompress(&bzs);
87 
88 	        switch (ret) {
89 	        case BZ_STREAM_END:
90 	        case BZ_OK:
91 	                if (ret == BZ_OK && end_of_file) {
92 				/*
93 				 * If we hit this after a stream end, consider
94 				 * it as the end of the whole file and don't
95 				 * bail out.
96 				 */
97 				if (cold == 1)
98 					ret = BZ_STREAM_END;
99 				else
100 					maybe_errx("truncated file");
101 			}
102 			cold = 0;
103 	                if (!tflag && bzs.avail_out != BUFLEN) {
104 				ssize_t	n;
105 
106 	                        n = write(out, outbuf, BUFLEN - bzs.avail_out);
107 	                        if (n < 0)
108 	                                maybe_err("write");
109 	                	bytes_out += n;
110 	                }
111 			if (ret == BZ_STREAM_END && !end_of_file) {
112 				if (BZ2_bzDecompressEnd(&bzs) != BZ_OK ||
113 				    BZ2_bzDecompressInit(&bzs, 0, 0) != BZ_OK)
114 					maybe_errx("bzip2 re-init");
115 				cold = 1;
116 				ret = BZ_OK;
117 			}
118 			break;
119 
120 	        case BZ_DATA_ERROR:
121 	                maybe_warnx("bzip2 data integrity error");
122 			break;
123 
124 	        case BZ_DATA_ERROR_MAGIC:
125 	                maybe_warnx("bzip2 magic number error");
126 			break;
127 
128 	        case BZ_MEM_ERROR:
129 	                maybe_warnx("bzip2 out of memory");
130 			break;
131 
132 		default:
133 			maybe_warnx("unknown bzip2 error: %d", ret);
134 			break;
135 	        }
136 	}
137 
138 	if (ret != BZ_STREAM_END || BZ2_bzDecompressEnd(&bzs) != BZ_OK)
139 	        return (-1);
140 
141 	return (bytes_out);
142 }
143 
144