55 lines
1.7 KiB
C
55 lines
1.7 KiB
C
/* Open a directory relative to another directory.
|
|
|
|
Copyright 2006-2022 Free Software Foundation, Inc.
|
|
|
|
This program is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation, either version 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <https://www.gnu.org/licenses/>.
|
|
|
|
Written by Jim Meyering and Paul Eggert. */
|
|
|
|
#include <config.h>
|
|
|
|
#include <opendirat.h>
|
|
|
|
#include <errno.h>
|
|
#include <fcntl--.h>
|
|
#include <unistd.h>
|
|
|
|
/* Relative to DIR_FD, open the directory DIR, passing EXTRA_FLAGS to
|
|
the underlying openat call. On success, store into *PNEW_FD the
|
|
underlying file descriptor of the newly opened directory and return
|
|
the directory stream. On failure, return NULL and set errno.
|
|
|
|
On success, *PNEW_FD is at least 3, so this is a "safer" function. */
|
|
|
|
DIR *
|
|
opendirat (int dir_fd, char const *dir, int extra_flags, int *pnew_fd)
|
|
{
|
|
int open_flags = (O_RDONLY | O_CLOEXEC | O_DIRECTORY | O_NOCTTY
|
|
| O_NONBLOCK | extra_flags);
|
|
int new_fd = openat (dir_fd, dir, open_flags);
|
|
|
|
if (new_fd < 0)
|
|
return NULL;
|
|
DIR *dirp = fdopendir (new_fd);
|
|
if (dirp)
|
|
*pnew_fd = new_fd;
|
|
else
|
|
{
|
|
int fdopendir_errno = errno;
|
|
close (new_fd);
|
|
errno = fdopendir_errno;
|
|
}
|
|
return dirp;
|
|
}
|