1/* Return basename of given pathname according to the weird XPG specification.
2 Copyright (C) 1997-2021 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <https://www.gnu.org/licenses/>. */
19
20#include <string.h>
21#include <libgen.h>
22
23
24char *
25__xpg_basename (char *filename)
26{
27 char *p;
28
29 if (filename == NULL || filename[0] == '\0')
30 /* We return a pointer to a static string containing ".". */
31 p = (char *) ".";
32 else
33 {
34 p = strrchr (filename, '/');
35
36 if (p == NULL)
37 /* There is no slash in the filename. Return the whole string. */
38 p = filename;
39 else
40 {
41 if (p[1] == '\0')
42 {
43 /* We must remove trailing '/'. */
44 while (p > filename && p[-1] == '/')
45 --p;
46
47 /* Now we can be in two situations:
48 a) the string only contains '/' characters, so we return
49 '/'
50 b) p points past the last component, but we have to remove
51 the trailing slash. */
52 if (p > filename)
53 {
54 *p-- = '\0';
55 while (p > filename && p[-1] != '/')
56 --p;
57 }
58 else
59 /* The last slash we already found is the right position
60 to return. */
61 while (p[1] != '\0')
62 ++p;
63 }
64 else
65 /* Go to the first character of the name. */
66 ++p;
67 }
68 }
69
70 return p;
71}
72