1 /* $NetBSD: dirname.c,v 1.14 2018/09/27 00:45:34 kre Exp $ */ 2 3 /*- 4 * Copyright (c) 1997, 2002 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Klaus Klein and Jason R. Thorpe. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #ifdef HAVE_CONFIG_H 33 # include <config.h> 34 #endif 35 #ifndef HAVE_DIRNAME 36 37 #include <sys/cdefs.h> 38 #if defined(LIBC_SCCS) && !defined(lint) 39 __RCSID("$NetBSD: dirname.c,v 1.14 2018/09/27 00:45:34 kre Exp $"); 40 #endif /* !LIBC_SCCS && !lint */ 41 42 #include <sys/param.h> 43 #ifdef HAVE_LIBGEN_H 44 #include <libgen.h> 45 #endif 46 #ifdef HAVE_LIMITS_H 47 #include <limits.h> 48 #endif 49 #ifdef HAVE_STRING_H 50 #include <string.h> 51 #endif 52 #ifndef PATH_MAX 53 # define PATH_MAX 1024 54 #endif 55 #ifndef MIN 56 # define MIN(a, b) ((a < b) ? a : b) 57 #endif 58 59 60 static size_t 61 xdirname_r(const char *path, char *buf, size_t buflen) 62 { 63 const char *endp; 64 size_t len; 65 66 /* 67 * If `path' is a null pointer or points to an empty string, 68 * return a pointer to the string ".". 69 */ 70 if (path == NULL || *path == '\0') { 71 path = "."; 72 len = 1; 73 goto out; 74 } 75 76 /* Strip trailing slashes, if any. */ 77 endp = path + strlen(path) - 1; 78 while (endp != path && *endp == '/') 79 endp--; 80 81 /* Find the start of the dir */ 82 while (endp > path && *endp != '/') 83 endp--; 84 85 if (endp == path) { 86 path = *endp == '/' ? "/" : "."; 87 len = 1; 88 goto out; 89 } 90 91 do 92 endp--; 93 while (endp > path && *endp == '/'); 94 95 len = endp - path + 1; 96 out: 97 if (buf != NULL && buflen != 0) { 98 buflen = MIN(len, buflen - 1); 99 if (buf != path) 100 memcpy(buf, path, buflen); 101 buf[buflen] = '\0'; 102 } 103 return len; 104 } 105 106 char * 107 dirname(char *path) 108 { 109 static char result[PATH_MAX]; 110 (void)xdirname_r(path, result, sizeof(result)); 111 return result; 112 } 113 114 #ifdef MAIN 115 #include <stdlib.h> 116 #include <stdio.h> 117 118 int 119 main(int argc, char *argv[]) 120 { 121 printf("%s\n", dirname(argv[1])); 122 exit(0); 123 } 124 #endif 125 #endif 126