Update.
[glibc.git] / stdlib / xpg_basename.c
blob0e36807165762c33662797837c66d57f64c1ea4c
1 /* Return basename of given pathname according to the weird XPG specification.
2 Copyright (C) 1997, 1999 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Library General Public License as
8 published by the Free Software Foundation; either version 2 of the
9 License, or (at your option) any later version.
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 Library General Public License for more details.
16 You should have received a copy of the GNU Library General Public
17 License along with the GNU C Library; see the file COPYING.LIB. If not,
18 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
21 #include <string.h>
22 #include <libgen.h>
25 char *
26 __xpg_basename (char *filename)
28 char *p;
30 if (filename == NULL || filename[0] == '\0')
31 /* We return a pointer to a static string containing ".". */
32 p = (char *) ".";
33 else
35 p = strrchr (filename, '/');
37 if (p == NULL)
38 /* There is no slash in the filename. Return the whole string. */
39 p = filename;
40 else
42 if (p[1] == '\0')
44 /* We must remove trailing '/'. */
45 while (p > filename && p[-1] == '/')
46 --p;
48 /* Now we can be in two situations:
49 a) the string only contains '/' characters, so we return
50 '/'
51 b) p points past the last component, but we have to remove
52 the trailing slash. */
53 if (p > filename)
55 *p-- = '\0';
56 while (p > filename && p[-1] != '/')
57 --p;
59 else
60 /* The last slash we already found is the right position
61 to return. */
62 while (p[1] != '\0')
63 ++p;
65 else
66 /* Go to the first character of the name. */
67 ++p;
71 return p;