1 /* $NetBSD: pwd.c,v 1.22 2011/08/29 14:51:19 joerg 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. 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 #include <sys/cdefs.h> 33 #ifndef lint 34 __COPYRIGHT("@(#) Copyright (c) 1991, 1993, 1994\ 35 The Regents of the University of California. All rights reserved."); 36 #endif /* not lint */ 37 38 #ifndef lint 39 #if 0 40 static char sccsid[] = "@(#)pwd.c 8.3 (Berkeley) 4/1/94"; 41 #else 42 __RCSID("$NetBSD: pwd.c,v 1.22 2011/08/29 14:51:19 joerg Exp $"); 43 #endif 44 #endif /* not lint */ 45 46 #include <sys/param.h> 47 #include <sys/stat.h> 48 #include <sys/types.h> 49 50 #include <err.h> 51 #include <errno.h> 52 #include <locale.h> 53 #include <stdio.h> 54 #include <stdlib.h> 55 #include <string.h> 56 #include <unistd.h> 57 58 static char *getcwd_logical(void); 59 __dead static void usage(void); 60 61 /* 62 * Note that EEE Std 1003.1, 2003 requires that the default be -L. 63 * This is inconsistent with the historic behaviour of everything 64 * except the ksh builtin. 65 * To avoid breaking scripts the default has been kept as -P. 66 * (Some scripts run /bin/pwd in order to get 'pwd -P'.) 67 */ 68 69 int 70 main(int argc, char *argv[]) 71 { 72 int ch, lFlag; 73 const char *p; 74 75 setprogname(argv[0]); 76 (void)setlocale(LC_ALL, ""); 77 78 lFlag = 0; 79 while ((ch = getopt(argc, argv, "LP")) != -1) { 80 switch (ch) { 81 case 'L': 82 lFlag = 1; 83 break; 84 case 'P': 85 lFlag = 0; 86 break; 87 case '?': 88 default: 89 usage(); 90 } 91 } 92 argc -= optind; 93 argv += optind; 94 95 if (argc != 0) 96 usage(); 97 98 if (lFlag) 99 p = getcwd_logical(); 100 else 101 p = NULL; 102 if (p == NULL) 103 p = getcwd(NULL, 0); 104 105 if (p == NULL) 106 err(EXIT_FAILURE, NULL); 107 108 (void)printf("%s\n", p); 109 110 exit(EXIT_SUCCESS); 111 /* NOTREACHED */ 112 } 113 114 static char * 115 getcwd_logical(void) 116 { 117 char *pwd; 118 struct stat s_pwd, s_dot; 119 120 /* Check $PWD -- if it's right, it's fast. */ 121 pwd = getenv("PWD"); 122 if (pwd == NULL) 123 return NULL; 124 if (pwd[0] != '/') 125 return NULL; 126 if (strstr(pwd, "/./") != NULL) 127 return NULL; 128 if (strstr(pwd, "/../") != NULL) 129 return NULL; 130 if (stat(pwd, &s_pwd) == -1 || stat(".", &s_dot) == -1) 131 return NULL; 132 if (s_pwd.st_dev != s_dot.st_dev || s_pwd.st_ino != s_dot.st_ino) 133 return NULL; 134 return pwd; 135 } 136 137 static void 138 usage(void) 139 { 140 (void)fprintf(stderr, "usage: %s [-LP]\n", getprogname()); 141 exit(EXIT_FAILURE); 142 /* NOTREACHED */ 143 } 144