lib/basename.c

   1 /* basename.c -- return the last element in a path
   2    Copyright (C) 1990, 1998, 1999 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software Foundation,
  16    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 #if HAVE_CONFIG_H
  19 # include <config.h>
  20 #endif
  21
  22 #ifndef FILESYSTEM_PREFIX_LEN
  23 # define FILESYSTEM_PREFIX_LEN(Filename) 0
  24 #endif
  25
  26 #ifndef PARAMS
  27 # if defined PROTOTYPES || (defined __STDC__ && __STDC__)
  28 #  define PARAMS(Args) Args
  29 # else
  30 #  define PARAMS(Args) ()
  31 # endif
  32 #endif
  33
  34 #ifndef ISSLASH
  35 # define ISSLASH(C) ((C) == '/')
  36 #endif
  37
  38 char *base_name PARAMS ((char const *name));
  39
  40 /* In general, we can't use the builtin `basename' function if available,
  41    since it has different meanings in different environments.
  42    In some environments the builtin `basename' modifies its argument.
  43    If NAME is all slashes, be sure to return `/'.  */
  44
  45 char *
  46 base_name (char const *name)
  47 {
  48   char const *base = name += FILESYSTEM_PREFIX_LEN (name);
  49   int all_slashes = 1;
  50   char const *p;
  51
  52   for (p = name; *p; p++)
  53     {
  54       if (ISSLASH (*p))
  55         base = p + 1;
  56       else
  57         all_slashes = 0;
  58     }
  59
  60   /* If NAME is all slashes, arrange to return `/'.  */
  61   if (*base == '\0' && ISSLASH (*name) && all_slashes)
  62     --base;
  63
  64   return (char *) base;
  65 }