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
61static size_t
62xdirname_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;
97out:
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
107char *
108dirname(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
119int
120main(int argc, char *argv[])
121{
122	printf("%s\n", dirname(argv[1]));
123	exit(0);
124}
125#endif
126#endif
127