1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 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. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #if 0 33 #ifndef lint 34 static char const copyright[] = 35 "@(#) Copyright (c) 1991, 1993, 1994\n\ 36 The Regents of the University of California. All rights reserved.\n"; 37 #endif /* not lint */ 38 39 #ifndef lint 40 static char sccsid[] = "@(#)pwd.c 8.3 (Berkeley) 4/1/94"; 41 #endif /* not lint */ 42 #endif 43 #include <sys/cdefs.h> 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 54 static char *getcwd_logical(void); 55 void usage(void); 56 57 int 58 main(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 96 void __dead2 97 usage(void) 98 { 99 100 (void)fprintf(stderr, "usage: pwd [-L | -P]\n"); 101 exit(1); 102 } 103 104 static char * 105 getcwd_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