1/*	$OpenBSD: dc.c,v 1.11 2009/10/27 23:59:37 deraadt Exp $	*/
2
3/*
4 * Copyright (c) 2003, Otto Moerbeek <otto@drijf.net>
5 * Copyright (c) 2009, Gabor Kovesdan <gabor@FreeBSD.org>
6 *
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 */
19
20#include <sys/cdefs.h>
21#include <sys/stat.h>
22
23#include <capsicum_helpers.h>
24#include <ctype.h>
25#include <err.h>
26#include <errno.h>
27#include <fcntl.h>
28#include <getopt.h>
29#include <stdio.h>
30#include <stdlib.h>
31#include <string.h>
32#include <unistd.h>
33
34#include "extern.h"
35
36#define	DC_VER		"1.3-FreeBSD"
37
38static void		 usage(void);
39
40extern char		*__progname;
41
42static struct source	 src;
43
44static const struct option long_options[] =
45{
46	{"expression",		required_argument,	NULL,	'e'},
47	{"file",		required_argument,	NULL,	'f'},
48	{"help",		no_argument,		NULL,	'h'},
49	{"version",		no_argument,		NULL,	'V'}
50};
51
52static void
53usage(void)
54{
55	fprintf(stderr, "usage: %s [-hVx] [-e expression] [file]\n",
56	    __progname);
57	exit(1);
58}
59
60static void
61procfd(int fd, char *fname) {
62	struct stat st;
63	FILE *file;
64
65	file = fdopen(fd, "r");
66	if (file == NULL)
67		err(1, "cannot open file %s", fname);
68	if (fstat(fileno(file), &st) == -1)
69		err(1, "%s", fname);
70	if (S_ISDIR(st.st_mode)) {
71		errno = EISDIR;
72		err(1, "%s", fname);
73	}
74	src_setstream(&src, file);
75	reset_bmachine(&src);
76	eval();
77	fclose(file);
78}
79
80int
81main(int argc, char *argv[])
82{
83	int ch, fd;
84	bool extended_regs = false, preproc_done = false;
85
86	/* accept and ignore a single dash to be 4.4BSD dc(1) compatible */
87	while ((ch = getopt_long(argc, argv, "e:f:hVx", long_options, NULL)) != -1) {
88		switch (ch) {
89		case 'e':
90			if (!preproc_done)
91				init_bmachine(extended_regs);
92			src_setstring(&src, optarg);
93			reset_bmachine(&src);
94			eval();
95			preproc_done = true;
96			break;
97		case 'f':
98			if (!preproc_done)
99				init_bmachine(extended_regs);
100			fd = open(optarg, O_RDONLY);
101			if (fd < 0)
102				err(1, "cannot open file %s", optarg);
103			procfd(fd, optarg);
104			preproc_done = true;
105			break;
106		case 'x':
107			extended_regs = true;
108			break;
109		case 'V':
110			fprintf(stderr, "%s (BSD bc) %s\n", __progname, DC_VER);
111			exit(0);
112			break;
113		case '-':
114			break;
115		case 'h':
116			/* FALLTHROUGH */
117		default:
118			usage();
119		}
120	}
121	argc -= optind;
122	argv += optind;
123
124	if (!preproc_done)
125		init_bmachine(extended_regs);
126	(void)setvbuf(stdout, NULL, _IOLBF, 0);
127	(void)setvbuf(stderr, NULL, _IOLBF, 0);
128
129	if (argc > 1)
130		usage();
131	if (argc == 1) {
132		fd = open(argv[0], O_RDONLY);
133		if (fd < 0)
134			err(1, "cannot open file %s", argv[0]);
135
136		if (caph_limit_stream(fd, CAPH_READ) < 0 ||
137		    caph_limit_stdio() < 0 ||
138		    caph_enter() < 0)
139			err(1, "capsicum");
140
141		procfd(fd, argv[0]);
142		preproc_done = true;
143	}
144	if (preproc_done)
145		return (0);
146
147	if (caph_limit_stdio() < 0 || caph_enter())
148		err(1, "capsicum");
149	src_setstream(&src, stdin);
150	reset_bmachine(&src);
151	eval();
152
153	return (0);
154}
155