xref: /freebsd/lib/libc/gen/sleep.c (revision 59c8e88e72633afbc47a4ace0d2170d00d51f7dc)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
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  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include "namespace.h"
33 #include <errno.h>
34 #include <limits.h>
35 #include <time.h>
36 #include <unistd.h>
37 #include "un-namespace.h"
38 
39 #include "libc_private.h"
40 
41 unsigned int __sleep(unsigned int);
42 
43 unsigned int
44 __sleep(unsigned int seconds)
45 {
46 	struct timespec time_to_sleep;
47 	struct timespec time_remaining;
48 
49 	/*
50 	 * Avoid overflow when `seconds' is huge.  This assumes that
51 	 * the maximum value for a time_t is >= INT_MAX.
52 	 */
53 	if (seconds > INT_MAX)
54 		return (seconds - INT_MAX + __sleep(INT_MAX));
55 
56 	time_to_sleep.tv_sec = seconds;
57 	time_to_sleep.tv_nsec = 0;
58 	if (((int (*)(const struct timespec *, struct timespec *))
59 	    (*__libsys_interposing_slot(INTERPOS_nanosleep)))(
60 	    &time_to_sleep, &time_remaining) != -1)
61 		return (0);
62 	if (errno != EINTR)
63 		return (seconds);		/* best guess */
64 	return (time_remaining.tv_sec +
65 	    (time_remaining.tv_nsec != 0)); /* round up */
66 }
67 
68 __weak_reference(__sleep, sleep);
69 __weak_reference(__sleep, _sleep);
70