xref: /freebsd/usr.bin/gzip/unbzip2.c (revision f4b37ed0f8b307b1f3f0f630ca725d68f1dff30d)
1 /*	$NetBSD: unbzip2.c,v 1.13 2009/12/05 03:23:37 mrg Exp $	*/
2 
3 /*-
4  * Copyright (c) 2006 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Simon Burge.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  *
31  * $FreeBSD$
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 	        if (bzs.avail_in == 0 && !end_of_file) {
69 			ssize_t	n;
70 
71 	                n = read(in, inbuf, BUFLEN);
72 	                if (n < 0)
73 	                        maybe_err("read");
74 	                if (n == 0)
75 	                        end_of_file = 1;
76 	                bzs.next_in = inbuf;
77 	                bzs.avail_in = n;
78 			if (bytes_in)
79 				*bytes_in += n;
80 	        }
81 
82 	        bzs.next_out = outbuf;
83 	        bzs.avail_out = BUFLEN;
84 	        ret = BZ2_bzDecompress(&bzs);
85 
86 	        switch (ret) {
87 	        case BZ_STREAM_END:
88 	        case BZ_OK:
89 	                if (ret == BZ_OK && end_of_file) {
90 				/*
91 				 * If we hit this after a stream end, consider
92 				 * it as the end of the whole file and don't
93 				 * bail out.
94 				 */
95 				if (cold == 1)
96 					ret = BZ_STREAM_END;
97 				else
98 					maybe_errx("truncated file");
99 			}
100 			cold = 0;
101 	                if (!tflag && bzs.avail_out != BUFLEN) {
102 				ssize_t	n;
103 
104 	                        n = write(out, outbuf, BUFLEN - bzs.avail_out);
105 	                        if (n < 0)
106 	                                maybe_err("write");
107 	                	bytes_out += n;
108 	                }
109 			if (ret == BZ_STREAM_END && !end_of_file) {
110 				if (BZ2_bzDecompressEnd(&bzs) != BZ_OK ||
111 				    BZ2_bzDecompressInit(&bzs, 0, 0) != BZ_OK)
112 					maybe_errx("bzip2 re-init");
113 				cold = 1;
114 				ret = BZ_OK;
115 			}
116 			break;
117 
118 	        case BZ_DATA_ERROR:
119 	                maybe_warnx("bzip2 data integrity error");
120 			break;
121 
122 	        case BZ_DATA_ERROR_MAGIC:
123 	                maybe_warnx("bzip2 magic number error");
124 			break;
125 
126 	        case BZ_MEM_ERROR:
127 	                maybe_warnx("bzip2 out of memory");
128 			break;
129 
130 		default:
131 			maybe_warnx("unknown bzip2 error: %d", ret);
132 			break;
133 	        }
134 	}
135 
136 	if (ret != BZ_STREAM_END || BZ2_bzDecompressEnd(&bzs) != BZ_OK)
137 	        return (-1);
138 
139 	return (bytes_out);
140 }
141 
142