1/*-
2 * Copyright (c) 1991, 1993, 1994
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#if 0
31#ifndef lint
32static char const copyright[] =
33"@(#) Copyright (c) 1991, 1993, 1994\n\
34	The Regents of the University of California.  All rights reserved.\n";
35#endif /* not lint */
36
37#ifndef lint
38static char sccsid[] = "@(#)pwd.c	8.3 (Berkeley) 4/1/94";
39#endif /* not lint */
40#endif
41#include <sys/cdefs.h>
42__FBSDID("$FreeBSD$");
43
44#include <sys/param.h>
45#include <sys/stat.h>
46#include <sys/types.h>
47
48#include <err.h>
49#include <errno.h>
50#include <stdio.h>
51#include <stdlib.h>
52#include <unistd.h>
53
54static char *getcwd_logical(void);
55void usage(void);
56
57int
58main(int argc, char *argv[])
59{
60	int physical;
61	int ch;
62	char *p;
63
64	physical = 1;
65	while ((ch = getopt(argc, argv, "LP")) != -1)
66		switch (ch) {
67		case 'L':
68			physical = 0;
69			break;
70		case 'P':
71			physical = 1;
72			break;
73		case '?':
74		default:
75			usage();
76		}
77	argc -= optind;
78	argv += optind;
79
80	if (argc != 0)
81		usage();
82
83	/*
84	 * If we're trying to find the logical current directory and that
85	 * fails, behave as if -P was specified.
86	 */
87	if ((!physical && (p = getcwd_logical()) != NULL) ||
88	    (p = getcwd(NULL, 0)) != NULL)
89		printf("%s\n", p);
90	else
91		err(1, ".");
92
93	exit(0);
94}
95
96void
97usage(void)
98{
99
100	(void)fprintf(stderr, "usage: pwd [-L | -P]\n");
101  	exit(1);
102}
103
104static char *
105getcwd_logical(void)
106{
107	struct stat lg, phy;
108	char *pwd;
109
110	/*
111	 * Check that $PWD is an absolute logical pathname referring to
112	 * the current working directory.
113	 */
114	if ((pwd = getenv("PWD")) != NULL && *pwd == '/') {
115		if (stat(pwd, &lg) == -1 || stat(".", &phy) == -1)
116			return (NULL);
117		if (lg.st_dev == phy.st_dev && lg.st_ino == phy.st_ino)
118			return (pwd);
119	}
120
121	errno = ENOENT;
122	return (NULL);
123}
124