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
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		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