xref: /netbsd-src/external/gpl2/gettext/dist/gettext-runtime/gnulib-lib/basename.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /* Return the name-within-directory of a file name.
2    Copyright (C) 1996-1999, 2000-2002, 2004, 2006 Free Software Foundation, Inc.
3 
4    NOTE: The canonical source of this file is maintained with the GNU C Library.
5    Bugs can be reported to bug-glibc@gnu.org.
6 
7    This program is free software; you can redistribute it and/or modify it
8    under the terms of the GNU General Public License as published by the
9    Free Software Foundation; either version 2, or (at your option) any
10    later version.
11 
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with this program; if not, write to the Free Software
19    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
20    USA.  */
21 
22 #include <config.h>
23 
24 /* Specification.  */
25 #include "basename.h"
26 
27 #if !(__GLIBC__ >= 2)
28 
29 #include <stdio.h>
30 #include <assert.h>
31 
32 #if defined _WIN32 || defined __WIN32__ || defined __CYGWIN__ || defined __EMX__ || defined __DJGPP__
33   /* Win32, Cygwin, OS/2, DOS */
34 # define HAS_DEVICE(P) \
35     ((((P)[0] >= 'A' && (P)[0] <= 'Z') || ((P)[0] >= 'a' && (P)[0] <= 'z')) \
36      && (P)[1] == ':')
37 # define FILE_SYSTEM_PREFIX_LEN(P) (HAS_DEVICE (P) ? 2 : 0)
38 # define ISSLASH(C) ((C) == '/' || (C) == '\\')
39 #endif
40 
41 #ifndef FILE_SYSTEM_PREFIX_LEN
42 # define FILE_SYSTEM_PREFIX_LEN(Filename) 0
43 #endif
44 
45 #ifndef ISSLASH
46 # define ISSLASH(C) ((C) == '/')
47 #endif
48 
49 #ifndef _LIBC
50 /* We cannot generally use the name `basename' since XPG defines an unusable
51    variant of the function but we cannot use it.  */
52 # undef basename
53 # define basename gnu_basename
54 #endif
55 
56 /* In general, we can't use the builtin `basename' function if available,
57    since it has different meanings in different environments.
58    In some environments the builtin `basename' modifies its argument.
59    If NAME is all slashes, be sure to return `/'.  */
60 
61 char *
basename(char const * name)62 basename (char const *name)
63 {
64   char const *base = name += FILE_SYSTEM_PREFIX_LEN (name);
65   int all_slashes = 1;
66   char const *p;
67 
68   for (p = name; *p; p++)
69     {
70       if (ISSLASH (*p))
71 	base = p + 1;
72       else
73 	all_slashes = 0;
74     }
75 
76   /* If NAME is all slashes, arrange to return `/'.  */
77   if (*base == '\0' && ISSLASH (*name) && all_slashes)
78     --base;
79 
80   /* Make sure the last byte is not a slash.  */
81   assert (all_slashes || !ISSLASH (*(p - 1)));
82 
83   return (char *) base;
84 }
85 
86 #endif
87