1/* Work around a bug of lstat on some systems
2
3   Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free
4   Software 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 3 of the License, or
9   (at your option) 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, see <http://www.gnu.org/licenses/>.  */
18
19/* written by Jim Meyering */
20
21#include <config.h>
22
23/* The specification of these functions is in sys_stat.h.  But we cannot
24   include this include file here, because on some systems, a
25   "#define lstat lstat64" is being used, and sys_stat.h deletes this
26   definition.  */
27
28#include <sys/types.h>
29#include <sys/stat.h>
30#include <string.h>
31#include <errno.h>
32
33/* lstat works differently on Linux and Solaris systems.  POSIX (see
34   `pathname resolution' in the glossary) requires that programs like
35   `ls' take into consideration the fact that FILE has a trailing slash
36   when FILE is a symbolic link.  On Linux and Solaris 10 systems, the
37   lstat function already has the desired semantics (in treating
38   `lstat ("symlink/", sbuf)' just like `lstat ("symlink/.", sbuf)',
39   but on Solaris 9 and earlier it does not.
40
41   If FILE has a trailing slash and specifies a symbolic link,
42   then use stat() to get more info on the referent of FILE.
43   If the referent is a non-directory, then set errno to ENOTDIR
44   and return -1.  Otherwise, return stat's result.  */
45
46int
47rpl_lstat (const char *file, struct stat *sbuf)
48{
49  size_t len;
50  int lstat_result = lstat (file, sbuf);
51
52  if (lstat_result != 0 || !S_ISLNK (sbuf->st_mode))
53    return lstat_result;
54
55  len = strlen (file);
56  if (len == 0 || file[len - 1] != '/')
57    return 0;
58
59  /* FILE refers to a symbolic link and the name ends with a slash.
60     Call stat() to get info about the link's referent.  */
61
62  /* If stat fails, then we do the same.  */
63  if (stat (file, sbuf) != 0)
64    return -1;
65
66  /* If FILE references a directory, return 0.  */
67  if (S_ISDIR (sbuf->st_mode))
68    return 0;
69
70  /* Here, we know stat succeeded and FILE references a non-directory.
71     But it was specified via a name including a trailing slash.
72     Fail with errno set to ENOTDIR to indicate the contradiction.  */
73  errno = ENOTDIR;
74  return -1;
75}
76