1/* Work around platform bugs in stat.
2   Copyright (C) 2009-2012 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 3 of the License, or
7   (at your option) 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, see <http://www.gnu.org/licenses/>.  */
16
17/* written by Eric Blake */
18
19/* If the user's config.h happens to include <sys/stat.h>, let it include only
20   the system's <sys/stat.h> here, so that orig_stat doesn't recurse to
21   rpl_stat.  */
22#define __need_system_sys_stat_h
23#include <config.h>
24
25/* Get the original definition of stat.  It might be defined as a macro.  */
26#include <sys/types.h>
27#include <sys/stat.h>
28#undef __need_system_sys_stat_h
29
30#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
31# if _GL_WINDOWS_64_BIT_ST_SIZE
32#  undef stat /* avoid warning on mingw64 with _FILE_OFFSET_BITS=64 */
33#  define stat _stati64
34#  define REPLACE_FUNC_STAT_DIR 1
35#  undef REPLACE_FUNC_STAT_FILE
36# elif REPLACE_FUNC_STAT_FILE
37/* mingw64 has a broken stat() function, based on _stat(), in libmingwex.a.
38   Bypass it.  */
39#  define stat _stat
40#  define REPLACE_FUNC_STAT_DIR 1
41#  undef REPLACE_FUNC_STAT_FILE
42# endif
43#endif
44
45static int
46orig_stat (const char *filename, struct stat *buf)
47{
48  return stat (filename, buf);
49}
50
51/* Specification.  */
52/* Write "sys/stat.h" here, not <sys/stat.h>, otherwise OSF/1 5.1 DTK cc
53   eliminates this include because of the preliminary #include <sys/stat.h>
54   above.  */
55#include "sys/stat.h"
56
57#include <errno.h>
58#include <limits.h>
59#include <stdbool.h>
60#include <string.h>
61#include "dosname.h"
62#include "verify.h"
63
64#if REPLACE_FUNC_STAT_DIR
65# include "pathmax.h"
66  /* The only known systems where REPLACE_FUNC_STAT_DIR is needed also
67     have a constant PATH_MAX.  */
68# ifndef PATH_MAX
69#  error "Please port this replacement to your platform"
70# endif
71#endif
72
73/* Store information about NAME into ST.  Work around bugs with
74   trailing slashes.  Mingw has other bugs (such as st_ino always
75   being 0 on success) which this wrapper does not work around.  But
76   at least this implementation provides the ability to emulate fchdir
77   correctly.  */
78
79int
80rpl_stat (char const *name, struct stat *st)
81{
82  int result = orig_stat (name, st);
83#if REPLACE_FUNC_STAT_FILE
84  /* Solaris 9 mistakenly succeeds when given a non-directory with a
85     trailing slash.  */
86  if (result == 0 && !S_ISDIR (st->st_mode))
87    {
88      size_t len = strlen (name);
89      if (ISSLASH (name[len - 1]))
90        {
91          errno = ENOTDIR;
92          return -1;
93        }
94    }
95#endif /* REPLACE_FUNC_STAT_FILE */
96#if REPLACE_FUNC_STAT_DIR
97
98  if (result == -1 && errno == ENOENT)
99    {
100      /* Due to mingw's oddities, there are some directories (like
101         c:\) where stat() only succeeds with a trailing slash, and
102         other directories (like c:\windows) where stat() only
103         succeeds without a trailing slash.  But we want the two to be
104         synonymous, since chdir() manages either style.  Likewise, Mingw also
105         reports ENOENT for names longer than PATH_MAX, when we want
106         ENAMETOOLONG, and for stat("file/"), when we want ENOTDIR.
107         Fortunately, mingw PATH_MAX is small enough for stack
108         allocation.  */
109      char fixed_name[PATH_MAX + 1] = {0};
110      size_t len = strlen (name);
111      bool check_dir = false;
112      verify (PATH_MAX <= 4096);
113      if (PATH_MAX <= len)
114        errno = ENAMETOOLONG;
115      else if (len)
116        {
117          strcpy (fixed_name, name);
118          if (ISSLASH (fixed_name[len - 1]))
119            {
120              check_dir = true;
121              while (len && ISSLASH (fixed_name[len - 1]))
122                fixed_name[--len] = '\0';
123              if (!len)
124                fixed_name[0] = '/';
125            }
126          else
127            fixed_name[len++] = '/';
128          result = orig_stat (fixed_name, st);
129          if (result == 0 && check_dir && !S_ISDIR (st->st_mode))
130            {
131              result = -1;
132              errno = ENOTDIR;
133            }
134        }
135    }
136#endif /* REPLACE_FUNC_STAT_DIR */
137  return result;
138}
139