sudo/lib/util/openat.c

64 lines
1.6 KiB
C

/*
* SPDX-License-Identifier: ISC
*
* Copyright (c) 2015, 2019-2020 Todd C. Miller <Todd.Miller@sudo.ws>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/*
* This is an open source non-commercial project. Dear PVS-Studio, please check it.
* PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
*/
#include <config.h>
#include <fcntl.h>
#include <unistd.h>
#include <sudo_compat.h>
#ifndef HAVE_OPENAT
int
sudo_openat(int dfd, const char *path, int flags, mode_t mode)
{
int fd, odfd;
if (dfd == AT_FDCWD)
return open(path, flags, mode);
/* Save cwd */
if ((odfd = open(".", O_RDONLY)) == -1)
return -1;
if (fchdir(dfd) == -1) {
close(odfd);
return -1;
}
fd = open(path, flags, mode);
/* Restore cwd */
if (fchdir(odfd) == -1) {
/* Should not happen */
if (fd != -1) {
close(fd);
fd = -1;
}
}
close(odfd);
return fd;
}
#endif /* HAVE_OPENAT */