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 * 3. 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 * @(#)pwd.c 8.3 (Berkeley) 4/1/94 30 * $FreeBSD: head/bin/pwd/pwd.c 141578 2005-02-09 17:37:39Z ru $ 31 */ 32 33 #include <sys/param.h> 34 #include <sys/stat.h> 35 #include <sys/types.h> 36 37 #include <err.h> 38 #include <errno.h> 39 #include <stdio.h> 40 #include <stdlib.h> 41 #include <unistd.h> 42 43 static char *getcwd_logical(void); 44 void usage(void); 45 46 int 47 main(int argc, char *argv[]) 48 { 49 int physical; 50 int ch; 51 char *p; 52 53 physical = 1; 54 while ((ch = getopt(argc, argv, "LP")) != -1) 55 switch (ch) { 56 case 'L': 57 physical = 0; 58 break; 59 case 'P': 60 physical = 1; 61 break; 62 case '?': 63 default: 64 usage(); 65 } 66 argc -= optind; 67 argv += optind; 68 69 if (argc != 0) 70 usage(); 71 72 /* 73 * If we're trying to find the logical current directory and that 74 * fails, behave as if -P was specified. 75 */ 76 if ((!physical && (p = getcwd_logical()) != NULL) || 77 (p = getcwd(NULL, 0)) != NULL) 78 printf("%s\n", p); 79 else 80 err(1, "."); 81 82 exit(0); 83 } 84 85 void 86 usage(void) 87 { 88 89 (void)fprintf(stderr, "usage: pwd [-L | -P]\n"); 90 exit(1); 91 } 92 93 static char * 94 getcwd_logical(void) 95 { 96 struct stat logic, phy; 97 char *pwd; 98 99 /* 100 * Check that $PWD is an absolute logical pathname referring to 101 * the current working directory. 102 */ 103 if ((pwd = getenv("PWD")) != NULL && *pwd == '/') { 104 if (stat(pwd, &logic) == -1 || stat(".", &phy) == -1) 105 return (NULL); 106 if (logic.st_dev == phy.st_dev && logic.st_ino == phy.st_ino) 107 return (pwd); 108 } 109 110 errno = ENOENT; 111 return (NULL); 112 } 113