xref: /netbsd/lib/libc/gen/usleep.c (revision 90275da6)
1 /*	$NetBSD: usleep.c,v 1.20 2012/06/25 22:32:44 abs Exp $	*/
2 
3 /*-
4  * Copyright (c) 1997 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by J.T. Conklin.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 __RCSID("$NetBSD: usleep.c,v 1.20 2012/06/25 22:32:44 abs Exp $");
35 #endif /* LIBC_SCCS and not lint */
36 
37 #include "namespace.h"
38 #include <errno.h>
39 #include <time.h>
40 #include <unistd.h>
41 
42 #ifdef __weak_alias
__weak_alias(usleep,_usleep)43 __weak_alias(usleep,_usleep)
44 #endif
45 
46 int
47 usleep(useconds_t useconds)
48 {
49 	struct timespec ts;
50 
51 	if (useconds == 0)
52 		return (0);
53 
54 	if (useconds >= 1000000) {
55 		errno = EINVAL;
56 		return (-1);
57 	}
58 
59 	ts.tv_sec  = 0;
60 	ts.tv_nsec = useconds * 1000;
61 
62 	nanosleep(&ts, NULL);
63 
64 	return (0);
65 }
66