xref: /netbsd-src/external/gpl2/xcvs/dist/lib/dirname.c (revision 5a6c14c844c4c665da5632061aebde7bb2cb5766)
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 #include <sys/cdefs.h>
20 __RCSID("$NetBSD: dirname.c,v 1.2 2016/05/17 14:00:09 christos Exp $");
21 
22 
23 #ifdef HAVE_CONFIG_H
24 # include <config.h>
25 #endif
26 
27 #include "dirname.h"
28 
29 #include <string.h>
30 #include "xalloc.h"
31 
32 /* Return the length of `dirname (FILE)', or zero if FILE is
33    in the working directory.  Works properly even if
34    there are trailing slashes (by effectively ignoring them).  */
35 size_t
dir_len(char const * file)36 dir_len (char const *file)
37 {
38   size_t prefix_length = FILE_SYSTEM_PREFIX_LEN (file);
39   size_t length;
40 
41   /* Strip the basename and any redundant slashes before it.  */
42   for (length = base_name (file) - file;  prefix_length < length;  length--)
43     if (! ISSLASH (file[length - 1]))
44       return length;
45 
46   /* But don't strip the only slash from "/".  */
47   return prefix_length + ISSLASH (file[prefix_length]);
48 }
49 
50 /* Return the leading directories part of FILE,
51    allocated with xmalloc.
52    Works properly even if there are trailing slashes
53    (by effectively ignoring them).  */
54 
55 char *
dir_name(char const * file)56 dir_name (char const *file)
57 {
58   size_t length = dir_len (file);
59   bool append_dot = (length == FILE_SYSTEM_PREFIX_LEN (file));
60   char *dir = xmalloc (length + append_dot + 1);
61   memcpy (dir, file, length);
62   if (append_dot)
63     dir[length++] = '.';
64   dir[length] = 0;
65   return dir;
66 }
67 
68 #ifdef TEST_DIRNAME
69 /*
70 
71 Run the test like this (expect no output):
72   gcc -DHAVE_CONFIG_H -DTEST_DIRNAME -I.. -O -Wall \
73      basename.c dirname.c xmalloc.c error.c
74   sed -n '/^BEGIN-DATA$/,/^END-DATA$/p' dirname.c|grep -v DATA|./a.out
75 
76 If it's been built on a DOS or Windows platforms, run another test like
77 this (again, expect no output):
78   sed -n '/^BEGIN-DOS-DATA$/,/^END-DOS-DATA$/p' dirname.c|grep -v DATA|./a.out
79 
80 BEGIN-DATA
81 foo//// .
82 bar/foo//// bar
83 foo/ .
84 / /
85 . .
86 a .
87 END-DATA
88 
89 BEGIN-DOS-DATA
90 c:///// c:/
91 c:/ c:/
92 c:/. c:/
93 c:foo c:.
94 c:foo/bar c:foo
95 END-DOS-DATA
96 
97 */
98 
99 # define MAX_BUFF_LEN 1024
100 # include <stdio.h>
101 
102 char *program_name;
103 
104 int
main(int argc,char * argv[])105 main (int argc, char *argv[])
106 {
107   char buff[MAX_BUFF_LEN + 1];
108 
109   program_name = argv[0];
110 
111   buff[MAX_BUFF_LEN] = 0;
112   while (fgets (buff, MAX_BUFF_LEN, stdin) && buff[0])
113     {
114       char file[MAX_BUFF_LEN];
115       char expected_result[MAX_BUFF_LEN];
116       char const *result;
117       sscanf (buff, "%s %s", file, expected_result);
118       result = dir_name (file);
119       if (strcmp (result, expected_result))
120 	printf ("%s: got %s, expected %s\n", file, result, expected_result);
121     }
122   return 0;
123 }
124 #endif
125