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/* $OpenBSD: pwd.c,v 1.12 2014/05/28 06:55:58 guenther Exp $ */
/* $NetBSD: pwd.c,v 1.22 2011/08/29 14:51:19 joerg 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/stat.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
extern char *__progname;
static char *getcwd_logical(void);
__dead static void usage(void);
int
main(int argc, char *argv[])
{
int ch, lFlag = 0;
const char *p;
while ((ch = getopt(argc, argv, "LP")) != -1) {
switch (ch) {
case 'L':
lFlag = 1;
break;
case 'P':
lFlag = 0;
break;
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);
puts(p);
exit(EXIT_SUCCESS);
}
static char *
getcwd_logical(void)
{
char *pwd, *p;
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;
/* check for . or .. components, including trailing ones */
for (p = pwd; *p != '\0'; p++)
if (p[0] == '/' && p[1] == '.') {
if (p[2] == '.')
p++;
if (p[2] == '\0' || p[2] == '/')
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)
{
fprintf(stderr, "usage: %s [-LP]\n", __progname);
exit(EXIT_FAILURE);
}
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