1 /* Id */
2
3 /*
4 * Copyright (c) 2013 Nicholas Marriott <nicm@users.sourceforge.net>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
15 * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
16 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19 #include <errno.h>
20 #include <fcntl.h>
21 #include <stdarg.h>
22 #include <unistd.h>
23
24 #include "tmux.h"
25
26 int
openat(int fd,const char * path,int flags,...)27 openat(int fd, const char *path, int flags, ...)
28 {
29 mode_t mode;
30 va_list ap;
31 int dotfd, retval, saved_errno;
32
33 if (flags & O_CREAT) {
34 va_start(ap, flags);
35 mode = va_arg(ap, mode_t);
36 va_end(ap);
37 } else
38 mode = 0;
39
40 dotfd = -1;
41 if (fd != AT_FDCWD) {
42 dotfd = open(".", O_RDONLY);
43 if (dotfd == -1)
44 return (-1);
45 if (fchdir(fd) != 0)
46 return (-1);
47 }
48
49 retval = open(path, flags, mode);
50
51 if (dotfd != -1) {
52 if (fchdir(dotfd) != 0) {
53 saved_errno = errno;
54 close(retval);
55 close(dotfd);
56 errno = saved_errno;
57 return (-1);
58 }
59 close(dotfd);
60 }
61
62 return (retval);
63 }
64