unbzip2.c revision 1.4 
1/*	$NetBSD: unbzip2.c,v 1.4 2004/04/25 16:20:33 mrg Exp $	*/
2
3/* This file is #included by gzip.c */
4
5static off_t
6unbzip2(int in, int out, char *pre, size_t prelen, off_t *bytes_in)
7{
8	int		ret, end_of_file;
9	size_t		n;
10	off_t		bytes_out = 0;
11	bz_stream	bzs;
12	static char	*inbuf, *outbuf;
13
14	if (inbuf == NULL && (inbuf = malloc(BUFLEN)) == NULL)
15	        maybe_err(1, "malloc");
16	if (outbuf == NULL && (outbuf = malloc(BUFLEN)) == NULL)
17	        maybe_err(1, "malloc");
18
19	bzs.bzalloc = NULL;
20	bzs.bzfree = NULL;
21	bzs.opaque = NULL;
22
23	end_of_file = 0;
24	ret = BZ2_bzDecompressInit(&bzs, 0, 0);
25	if (ret != BZ_OK)
26	        maybe_errx(1, "bzip2 init");
27
28	/* Prepend. */
29	bzs.avail_in = prelen;
30	bzs.next_in = pre;
31
32	if (bytes_in)
33		*bytes_in = prelen;
34
35	while (ret != BZ_STREAM_END) {
36	        if (bzs.avail_in == 0 && !end_of_file) {
37	                n = read(in, inbuf, BUFLEN);
38	                if (n < 0)
39	                        maybe_err(1, "read");
40	                if (n == 0)
41	                        end_of_file = 1;
42	                bzs.next_in = inbuf;
43	                bzs.avail_in = n;
44			if (bytes_in)
45				*bytes_in += n;
46	        }
47
48	        bzs.next_out = outbuf;
49	        bzs.avail_out = BUFLEN;
50	        ret = BZ2_bzDecompress(&bzs);
51
52	        switch (ret) {
53	        case BZ_STREAM_END:
54	        case BZ_OK:
55	                if (ret == BZ_OK && end_of_file)
56	                        maybe_err(1, "read");
57	                if (!tflag) {
58	                        n = write(out, outbuf, BUFLEN - bzs.avail_out);
59	                        if (n < 0)
60	                                maybe_err(1, "write");
61	                }
62	                bytes_out += n;
63	                break;
64
65	        case BZ_DATA_ERROR:
66	                maybe_errx(1, "bzip2 data integrity error");
67	        case BZ_DATA_ERROR_MAGIC:
68	                maybe_errx(1, "bzip2 magic number error");
69	        case BZ_MEM_ERROR:
70	                maybe_errx(1, "bzip2 out of memory");
71	        }
72	}
73
74	if (BZ2_bzDecompressEnd(&bzs) != BZ_OK)
75	        return (0);
76
77	return (bytes_out);
78}
79