*-map tests: Fix compilation error.
[gnulib.git] / lib / fstatat.c
blob515b569399190311ce1d298eda75000d9764e3fd
1 /* Work around an fstatat bug on Solaris 9.
3 Copyright (C) 2006, 2009-2019 Free Software Foundation, Inc.
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <https://www.gnu.org/licenses/>. */
18 /* Written by Paul Eggert and Jim Meyering. */
20 /* If the user's config.h happens to include <sys/stat.h>, let it include only
21 the system's <sys/stat.h> here, so that orig_fstatat doesn't recurse to
22 rpl_fstatat. */
23 #define __need_system_sys_stat_h
24 #include <config.h>
26 /* Get the original definition of fstatat. It might be defined as a macro. */
27 #include <sys/types.h>
28 #include <sys/stat.h>
29 #undef __need_system_sys_stat_h
31 #if HAVE_FSTATAT && HAVE_WORKING_FSTATAT_ZERO_FLAG
32 static int
33 orig_fstatat (int fd, char const *filename, struct stat *buf, int flags)
35 return fstatat (fd, filename, buf, flags);
37 #endif
39 /* Write "sys/stat.h" here, not <sys/stat.h>, otherwise OSF/1 5.1 DTK cc
40 eliminates this include because of the preliminary #include <sys/stat.h>
41 above. */
42 #include "sys/stat.h"
44 #include "stat-time.h"
46 #include <errno.h>
47 #include <fcntl.h>
48 #include <string.h>
50 #if HAVE_FSTATAT && HAVE_WORKING_FSTATAT_ZERO_FLAG
52 # ifndef LSTAT_FOLLOWS_SLASHED_SYMLINK
53 # define LSTAT_FOLLOWS_SLASHED_SYMLINK 0
54 # endif
56 static int
57 normal_fstatat (int fd, char const *file, struct stat *st, int flag)
59 return stat_time_normalize (orig_fstatat (fd, file, st, flag), st);
62 /* fstatat should always follow symbolic links that end in /, but on
63 Solaris 9 it doesn't if AT_SYMLINK_NOFOLLOW is specified.
64 Likewise, trailing slash on a non-directory should be an error.
65 These are the same problems that lstat.c and stat.c address, so
66 solve it in a similar way.
68 AIX 7.1 fstatat (AT_FDCWD, ..., 0) always fails, which is a bug.
69 Work around this bug if FSTATAT_AT_FDCWD_0_BROKEN is nonzero. */
71 int
72 rpl_fstatat (int fd, char const *file, struct stat *st, int flag)
74 int result = normal_fstatat (fd, file, st, flag);
75 size_t len;
77 if (LSTAT_FOLLOWS_SLASHED_SYMLINK || result != 0)
78 return result;
79 len = strlen (file);
80 if (flag & AT_SYMLINK_NOFOLLOW)
82 /* Fix lstat behavior. */
83 if (file[len - 1] != '/' || S_ISDIR (st->st_mode))
84 return 0;
85 if (!S_ISLNK (st->st_mode))
87 errno = ENOTDIR;
88 return -1;
90 result = normal_fstatat (fd, file, st, flag & ~AT_SYMLINK_NOFOLLOW);
92 /* Fix stat behavior. */
93 if (result == 0 && !S_ISDIR (st->st_mode) && file[len - 1] == '/')
95 errno = ENOTDIR;
96 return -1;
98 return result;
101 #else /* ! (HAVE_FSTATAT && HAVE_WORKING_FSTATAT_ZERO_FLAG) */
103 /* On mingw, the gnulib <sys/stat.h> defines 'stat' as a function-like
104 macro; but using it in AT_FUNC_F2 causes compilation failure
105 because the preprocessor sees a use of a macro that requires two
106 arguments but is only given one. Hence, we need an inline
107 forwarder to get past the preprocessor. */
108 static int
109 stat_func (char const *name, struct stat *st)
111 return stat (name, st);
114 /* Likewise, if there is no native 'lstat', then the gnulib
115 <sys/stat.h> defined it as stat, which also needs adjustment. */
116 # if !HAVE_LSTAT
117 # undef lstat
118 # define lstat stat_func
119 # endif
121 /* Replacement for Solaris' function by the same name.
122 <https://www.google.com/search?q=fstatat+site:docs.oracle.com>
123 First, try to simulate it via l?stat ("/proc/self/fd/FD/FILE").
124 Failing that, simulate it via save_cwd/fchdir/(stat|lstat)/restore_cwd.
125 If either the save_cwd or the restore_cwd fails (relatively unlikely),
126 then give a diagnostic and exit nonzero.
127 Otherwise, this function works just like Solaris' fstatat. */
129 # define AT_FUNC_NAME fstatat
130 # define AT_FUNC_F1 lstat
131 # define AT_FUNC_F2 stat_func
132 # define AT_FUNC_USE_F1_COND AT_SYMLINK_NOFOLLOW
133 # define AT_FUNC_POST_FILE_PARAM_DECLS , struct stat *st, int flag
134 # define AT_FUNC_POST_FILE_ARGS , st
135 # include "at-func.c"
136 # undef AT_FUNC_NAME
137 # undef AT_FUNC_F1
138 # undef AT_FUNC_F2
139 # undef AT_FUNC_USE_F1_COND
140 # undef AT_FUNC_POST_FILE_PARAM_DECLS
141 # undef AT_FUNC_POST_FILE_ARGS
143 #endif /* !HAVE_FSTATAT */