xref: /freebsd/contrib/openbsm/bin/auditdistd/openat.h (revision 7661de35d15f582ab33e3bd6b8d909601557e436)
1 /*-
2  * Copyright (c) 2012 The FreeBSD Foundation
3  * All rights reserved.
4  *
5  * This software was developed by Pawel Jakub Dawidek under sponsorship from
6  * the FreeBSD Foundation.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $P4: //depot/projects/trustedbsd/openbsm/bin/auditdistd/openat.h#1 $
30  */
31 
32 #ifndef	_OPENAT_H_
33 #define	_OPENAT_H_
34 
35 #include <fcntl.h>
36 #include <stdarg.h>
37 #include <unistd.h>
38 
39 static int
40 openat(int fd, const char *path, int flags, ...)
41 {
42 	int cfd, ffd, error;
43 
44 	cfd = open(".", O_RDONLY | O_DIRECTORY);
45 	if (cfd == -1)
46 		return (-1);
47 
48 	if (fchdir(fd) == -1) {
49 		error = errno;
50 		(void)close(cfd);
51 		errno = error;
52 		return (-1);
53 	}
54 
55 	if ((flags & O_CREAT) != 0) {
56 		va_list ap;
57 		int mode;
58 
59 		va_start(ap, flags);
60 		mode = va_arg(ap, int);
61 		va_end(ap);
62 
63 		ffd = open(path, flags, mode);
64 	} else {
65 		ffd = open(path, flags);
66 	}
67 
68 	error = errno;
69 	(void)fchdir(cfd);
70 	(void)close(cfd);
71 	errno = error;
72 	return (ffd);
73 }
74 
75 #endif	/* !_OPENAT_H_ */
76