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).  */
32size_t
33dir_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
52char *
53dir_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
68Run 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
73If it's been built on a DOS or Windows platforms, run another test like
74this (again, expect no output):
75  sed -n '/^BEGIN-DOS-DATA$/,/^END-DOS-DATA$/p' dirname.c|grep -v DATA|./a.out
76
77BEGIN-DATA
78foo//// .
79bar/foo//// bar
80foo/ .
81/ /
82. .
83a .
84END-DATA
85
86BEGIN-DOS-DATA
87c:///// c:/
88c:/ c:/
89c:/. c:/
90c:foo c:.
91c:foo/bar c:foo
92END-DOS-DATA
93
94*/
95
96# define MAX_BUFF_LEN 1024
97# include <stdio.h>
98
99char *program_name;
100
101int
102main (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