cosmopolitan/libc/calls/fstatat.c

50 lines
2.7 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ 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; version 2 of the License. │
│ │
│ 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, write to the Free Software │
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
│ 02110-1301 USA │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/calls/internal.h"
#include "libc/errno.h"
#include "libc/sysv/consts/at.h"
/**
* Performs stat() w/ features for threaded apps.
*
* @param dirfd can be AT_FDCWD or an open directory descriptor, and is
* ignored if pathname is absolute
* @param flags can have AT_{EMPTY_PATH,NO_AUTOMOUNT,SYMLINK_NOFOLLOW}
* @return 0 on success, or -1 w/ errno
* @asyncsignalsafe
*/
int fstatat(int dirfd, const char *pathname, struct stat *st, uint32_t flags) {
int olderr = errno;
int rc = fstatat$sysv(dirfd, pathname, st, flags);
if (rc != -1) {
stat2linux(st);
} else if (errno == ENOSYS && dirfd == AT_FDCWD) {
if (!flags) {
errno = olderr;
rc = stat(pathname, st);
} else if (flags == AT_SYMLINK_NOFOLLOW) {
errno = olderr;
rc = lstat(pathname, st);
}
}
return rc;
}