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
xdirname_r(const char * path,char * buf,size_t buflen)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 *
dirname(char * path)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
main(int argc,char * argv[])119 main(int argc, char *argv[])
120 {
121 printf("%s\n", dirname(argv[1]));
122 exit(0);
123 }
124 #endif
125 #endif
126