1 /* Copyright (C) 2005-2022 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library 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 GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <dirent.h>
19 #include <errno.h>
20 #include <fcntl.h>
21 #include <stddef.h>
22 #include <sys/stat.h>
23 
24 #include <not-cancel.h>
25 
26 
27 DIR *
__fdopendir(int fd)28 __fdopendir (int fd)
29 {
30   struct __stat64_t64 statbuf;
31 
32   if (__glibc_unlikely (__fstat64_time64 (fd, &statbuf) < 0))
33     return NULL;
34   if (__glibc_unlikely (! S_ISDIR (statbuf.st_mode)))
35     {
36       __set_errno (ENOTDIR);
37       return NULL;
38     }
39 
40   /* Make sure the descriptor allows for reading.  */
41   int flags = __fcntl64_nocancel (fd, F_GETFL);
42   if (__glibc_unlikely (flags == -1))
43     return NULL;
44   if (__glibc_unlikely ((flags & O_ACCMODE) == O_WRONLY))
45     {
46       __set_errno (EINVAL);
47       return NULL;
48     }
49 
50   return __alloc_dir (fd, false, flags, &statbuf);
51 }
52 weak_alias (__fdopendir, fdopendir)
53