1/*
2 * Copyright (c) 2014 Spectra Logic Corporation
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions, and the following disclaimer,
10 *    without modification.
11 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
12 *    substantially similar to the "NO WARRANTY" disclaimer below
13 *    ("Disclaimer") and any redistribution must be conditioned upon
14 *    including a substantially similar Disclaimer requirement for further
15 *    binary redistribution.
16 *
17 * NO WARRANTY
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
26 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
27 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGES.
29 *
30 * Authors: Alan Somers         (Spectra Logic Corporation)
31 *
32 * $FreeBSD: stable/11/tests/sys/net/randsleep.c 329874 2018-02-23 18:18:42Z asomers $
33 */
34
35#include <errno.h>
36#include <stdio.h>
37#include <stdlib.h>
38#include <unistd.h>
39
40#define RANDOM_MAX ((1<<31) - 1)
41
42int main(int argc, char** argv){
43	useconds_t max_usecs, usecs;
44	double frac;
45
46	if (argc != 2) {
47		printf("Usage: randsleep <max_microseconds>\n");
48		exit(2);
49	}
50
51	errno = 0;
52	max_usecs = (useconds_t)strtol(argv[1], NULL, 0);
53	if (errno != 0) {
54		perror("strtol");
55		exit(1);
56	}
57	srandomdev();
58	frac = (double)random() / (double)RANDOM_MAX;
59	usecs = (useconds_t)((double)max_usecs * frac);
60	usleep(usecs);
61
62	return (0);
63}
64