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: src/usr.bin/gzip/unbzip2.c,v 1.5 2010/04/07 22:54:53 delphij Exp $
32 */
33
34/* This file is #included by gzip.c */
35
36static off_t
37unbzip2(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