NetBSD/bin/pwd/pwd.c

144 lines
3.7 KiB
C

/* $NetBSD: pwd.c,v 1.21 2008/07/20 00:52:40 lukem Exp $ */
/*
* Copyright (c) 1991, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1991, 1993, 1994\
The Regents of the University of California. All rights reserved.");
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)pwd.c 8.3 (Berkeley) 4/1/94";
#else
__RCSID("$NetBSD: pwd.c,v 1.21 2008/07/20 00:52:40 lukem Exp $");
#endif
#endif /* not lint */
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <err.h>
#include <errno.h>
#include <locale.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
static char *getcwd_logical(void);
static void usage(void);
/*
* Note that EEE Std 1003.1, 2003 requires that the default be -L.
* This is inconsistent with the historic behaviour of everything
* except the ksh builtin.
* To avoid breaking scripts the default has been kept as -P.
* (Some scripts run /bin/pwd in order to get 'pwd -P'.)
*/
int
main(int argc, char *argv[])
{
int ch, lFlag;
const char *p;
setprogname(argv[0]);
(void)setlocale(LC_ALL, "");
lFlag = 0;
while ((ch = getopt(argc, argv, "LP")) != -1) {
switch (ch) {
case 'L':
lFlag = 1;
break;
case 'P':
lFlag = 0;
break;
case '?':
default:
usage();
}
}
argc -= optind;
argv += optind;
if (argc != 0)
usage();
if (lFlag)
p = getcwd_logical();
else
p = NULL;
if (p == NULL)
p = getcwd(NULL, 0);
if (p == NULL)
err(EXIT_FAILURE, NULL);
(void)printf("%s\n", p);
exit(EXIT_SUCCESS);
/* NOTREACHED */
}
static char *
getcwd_logical(void)
{
char *pwd;
struct stat s_pwd, s_dot;
/* Check $PWD -- if it's right, it's fast. */
pwd = getenv("PWD");
if (pwd == NULL)
return NULL;
if (pwd[0] != '/')
return NULL;
if (strstr(pwd, "/./") != NULL)
return NULL;
if (strstr(pwd, "/../") != NULL)
return NULL;
if (stat(pwd, &s_pwd) == -1 || stat(".", &s_dot) == -1)
return NULL;
if (s_pwd.st_dev != s_dot.st_dev || s_pwd.st_ino != s_dot.st_ino)
return NULL;
return pwd;
}
static void
usage(void)
{
(void)fprintf(stderr, "usage: %s [-LP]\n", getprogname());
exit(EXIT_FAILURE);
/* NOTREACHED */
}