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      1 /* dirname.c -- return all but the last element in a file name
      2 
      3    Copyright (C) 1990, 1998, 2000, 2001, 2003, 2004, 2005 Free Software
      4    Foundation, Inc.
      5 
      6    This program is free software; you can redistribute it and/or modify
      7    it under the terms of the GNU General Public License as published by
      8    the Free Software Foundation; either version 2, or (at your option)
      9    any later version.
     10 
     11    This program 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
     14    GNU General Public License for more details.
     15 
     16    You should have received a copy of the GNU General Public License
     17    along with this program; if not, write to the Free Software Foundation,
     18    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
     19 
     20 #ifdef HAVE_CONFIG_H
     21 # include <config.h>
     22 #endif
     23 
     24 #include "dirname.h"
     25 
     26 #include <string.h>
     27 #include "xalloc.h"
     28 
     29 /* Return the length of `dirname (FILE)', or zero if FILE is
     30    in the working directory.  Works properly even if
     31    there are trailing slashes (by effectively ignoring them).  */
     32 size_t
     33 dir_len (char const *file)
     34 {
     35   size_t prefix_length = FILE_SYSTEM_PREFIX_LEN (file);
     36   size_t length;
     37 
     38   /* Strip the basename and any redundant slashes before it.  */
     39   for (length = base_name (file) - file;  prefix_length < length;  length--)
     40     if (! ISSLASH (file[length - 1]))
     41       return length;
     42 
     43   /* But don't strip the only slash from "/".  */
     44   return prefix_length + ISSLASH (file[prefix_length]);
     45 }
     46 
     47 /* Return the leading directories part of FILE,
     48    allocated with xmalloc.
     49    Works properly even if there are trailing slashes
     50    (by effectively ignoring them).  */
     51 
     52 char *
     53 dir_name (char const *file)
     54 {
     55   size_t length = dir_len (file);
     56   bool append_dot = (length == FILE_SYSTEM_PREFIX_LEN (file));
     57   char *dir = xmalloc (length + append_dot + 1);
     58   memcpy (dir, file, length);
     59   if (append_dot)
     60     dir[length++] = '.';
     61   dir[length] = 0;
     62   return dir;
     63 }
     64 
     65 #ifdef TEST_DIRNAME
     66 /*
     67 
     68 Run the test like this (expect no output):
     69   gcc -DHAVE_CONFIG_H -DTEST_DIRNAME -I.. -O -Wall \
     70      basename.c dirname.c xmalloc.c error.c
     71   sed -n '/^BEGIN-DATA$/,/^END-DATA$/p' dirname.c|grep -v DATA|./a.out
     72 
     73 If it's been built on a DOS or Windows platforms, run another test like
     74 this (again, expect no output):
     75   sed -n '/^BEGIN-DOS-DATA$/,/^END-DOS-DATA$/p' dirname.c|grep -v DATA|./a.out
     76 
     77 BEGIN-DATA
     78 foo//// .
     79 bar/foo//// bar
     80 foo/ .
     81 / /
     82 . .
     83 a .
     84 END-DATA
     85 
     86 BEGIN-DOS-DATA
     87 c:///// c:/
     88 c:/ c:/
     89 c:/. c:/
     90 c:foo c:.
     91 c:foo/bar c:foo
     92 END-DOS-DATA
     93 
     94 */
     95 
     96 # define MAX_BUFF_LEN 1024
     97 # include <stdio.h>
     98 
     99 char *program_name;
    100 
    101 int
    102 main (int argc, char *argv[])
    103 {
    104   char buff[MAX_BUFF_LEN + 1];
    105 
    106   program_name = argv[0];
    107 
    108   buff[MAX_BUFF_LEN] = 0;
    109   while (fgets (buff, MAX_BUFF_LEN, stdin) && buff[0])
    110     {
    111       char file[MAX_BUFF_LEN];
    112       char expected_result[MAX_BUFF_LEN];
    113       char const *result;
    114       sscanf (buff, "%s %s", file, expected_result);
    115       result = dir_name (file);
    116       if (strcmp (result, expected_result))
    117 	printf ("%s: got %s, expected %s\n", file, result, expected_result);
    118     }
    119   return 0;
    120 }
    121 #endif
    122