xref: /freebsd/lib/libc/gen/dup3.c (revision 49b49cda41feabe3439f7318e8bf40e3896c7bf4)
1 /*-
2  * Copyright (c) 2012 Jukka A. Ukkonen
3  * All rights reserved.
4  *
5  * This software was developed by Jukka Ukkonen for FreeBSD.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include "namespace.h"
33 #include <unistd.h>
34 #include <fcntl.h>
35 #include <errno.h>
36 #include "un-namespace.h"
37 
38 int __dup3(int, int, int);
39 
40 int
41 __dup3(int oldfd, int newfd, int flags)
42 {
43 	int how;
44 
45 	if (oldfd == newfd) {
46 		errno = EINVAL;
47 		return (-1);
48 	}
49 
50 	if (flags & ~O_CLOEXEC) {
51 		errno = EINVAL;
52 		return (-1);
53 	}
54 
55 	how = (flags & O_CLOEXEC) ? F_DUP2FD_CLOEXEC : F_DUP2FD;
56 
57 	return (_fcntl(oldfd, how, newfd));
58 }
59 
60 __weak_reference(__dup3, dup3);
61 __weak_reference(__dup3, _dup3);
62