pwd/pwd.c

   1 /*      $NetBSD: pwd.c,v 1.10 1998/07/28 05:31:26 mycroft Exp $ */
   2
   3 /*
   4  * Copyright (c) 1991, 1993, 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *      This product includes software developed by the University of
  18  *      California, Berkeley and its contributors.
  19  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include <sys/cdefs.h>
  37 #ifndef lint
  38 __COPYRIGHT("@(#) Copyright (c) 1991, 1993, 1994\n\
  39         The Regents of the University of California.  All rights reserved.\n");
  40 #endif /* not lint */
  41
  42 #ifndef lint
  43 #if 0
  44 static char sccsid[] = "@(#)pwd.c       8.3 (Berkeley) 4/1/94";
  45 #else
  46 __RCSID("$NetBSD: pwd.c,v 1.10 1998/07/28 05:31:26 mycroft Exp $");
  47 #endif
  48 #endif /* not lint */
  49
  50 #include <err.h>
  51 #include <stdio.h>
  52 #include <stdlib.h>
  53 #include <unistd.h>
  54 #include <sys/param.h>
  55 #include <sys/stat.h>
  56 #include <errno.h>
  57 #include <string.h>
  58
  59 char *getcwd_logical __P((char *, size_t));
  60 void  usage __P((void));
  61 int   main __P((int, char *[]));
  62
  63 #ifdef __APPLE__
  64 char
  65 *getcwd_physical(pt, size)
  66         char *pt;
  67         size_t size;
  68 {
  69         unsetenv("PWD");
  70         return getcwd(pt, size);
  71 }
  72 #define getcwd getcwd_physical
  73 #endif
  74
  75 int
  76 main(argc, argv)
  77         int argc;
  78         char *argv[];
  79 {
  80         int ch;
  81         int lFlag=0;
  82         char *p = NULL;
  83
  84         while ((ch = getopt(argc, argv, "LP")) != -1)
  85                 switch (ch) {
  86                 case 'L':
  87                         lFlag=1;
  88                         break;
  89                 case 'P':
  90                         lFlag=0;
  91                         break;
  92                 case '?':
  93                 default:
  94                         usage();
  95                 }
  96         argc -= optind;
  97         argv += optind;
  98
  99         if (argc != 0)
 100                 usage();
 101
 102         if (lFlag)
 103                 p = getcwd_logical(NULL, 0);
 104         else
 105                 p = getcwd(NULL, 0);
 106
 107         if (p == NULL) err(1, "%s", "");
 108
 109         (void)printf("%s\n", p);
 110
 111         exit(0);
 112         /* NOTREACHED */
 113 }
 114
 115 char *
 116 getcwd_logical(pt, size)
 117         char *pt;
 118         size_t size;
 119 {
 120         char *pwd;
 121         size_t pwdlen;
 122         dev_t dev;
 123         ino_t ino;
 124         struct stat s;
 125
 126         /* Check $PWD -- if it's right, it's fast. */
 127         if ((pwd = getenv("PWD")) != NULL && pwd[0] == '/' && stat(pwd, &s) != -1) {
 128                 dev = s.st_dev;
 129                 ino = s.st_ino;
 130                 if (stat(".", &s) != -1 && dev == s.st_dev && ino == s.st_ino) {
 131                         pwdlen = strlen(pwd);
 132                         if (pt) {
 133                                 if (!size) {
 134                                         errno = EINVAL;
 135                                         return (NULL);
 136                                 }
 137                                 if (pwdlen + 1 > size) {
 138                                         errno = ERANGE;
 139                                         return (NULL);
 140                                 }
 141                         } else if ((pt = malloc(pwdlen + 1)) == NULL) {
 142                                 errno = ENOMEM;
 143                                 return (NULL);
 144                         }
 145                         memmove(pt, pwd, pwdlen);
 146                         pt[pwdlen] = '\0';
 147                         return (pt);
 148                 }
 149         }
 150
 151         return (NULL);
 152 }
 153
 154 void
 155 usage()
 156 {
 157         (void)fprintf(stderr, "usage: pwd [-LP]\n");
 158         exit(1);
 159         /* NOTREACHED */
 160 }