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 "namespace.h" 43 #include <sys/param.h> 44 #ifdef HAVE_LIBGEN_H 45 #include <libgen.h> 46 #endif 47 #ifdef HAVE_LIMITS_H 48 #include <limits.h> 49 #endif 50 #ifdef HAVE_STRING_H 51 #include <string.h> 52 #endif 53 #ifndef PATH_MAX 54 # define PATH_MAX 1024 55 #endif 56 #ifndef MIN 57 # define MIN(a, b) ((a < b) ? a : b) 58 #endif 59 60 61 static size_t 62 xdirname_r(const char *path, char *buf, size_t buflen) 63 { 64 const char *endp; 65 size_t len; 66 67 /* 68 * If `path' is a null pointer or points to an empty string, 69 * return a pointer to the string ".". 70 */ 71 if (path == NULL || *path == '\0') { 72 path = "."; 73 len = 1; 74 goto out; 75 } 76 77 /* Strip trailing slashes, if any. */ 78 endp = path + strlen(path) - 1; 79 while (endp != path && *endp == '/') 80 endp--; 81 82 /* Find the start of the dir */ 83 while (endp > path && *endp != '/') 84 endp--; 85 86 if (endp == path) { 87 path = *endp == '/' ? "/" : "."; 88 len = 1; 89 goto out; 90 } 91 92 do 93 endp--; 94 while (endp > path && *endp == '/'); 95 96 len = endp - path + 1; 97 out: 98 if (buf != NULL && buflen != 0) { 99 buflen = MIN(len, buflen - 1); 100 if (buf != path) 101 memcpy(buf, path, buflen); 102 buf[buflen] = '\0'; 103 } 104 return len; 105 } 106 107 char * 108 dirname(char *path) 109 { 110 static char result[PATH_MAX]; 111 (void)xdirname_r(path, result, sizeof(result)); 112 return result; 113 } 114 115 #ifdef MAIN 116 #include <stdlib.h> 117 #include <stdio.h> 118 119 int 120 main(int argc, char *argv[]) 121 { 122 printf("%s\n", dirname(argv[1])); 123 exit(0); 124 } 125 #endif 126 #endif 127