xref: /haiku/src/libs/compat/freebsd_network/fbsd_time.c (revision 9760dcae2038d47442f4658c2575844c6cf92c40)
1  /*-
2   * Copyright (c) 1982, 1986, 1989, 1993
3   *	The Regents of the University of California.  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   * 2. Redistributions in binary form must reproduce the above copyright
11   *    notice, this list of conditions and the following disclaimer in the
12   *    documentation and/or other materials provided with the distribution.
13   * 4. Neither the name of the University nor the names of its contributors
14   *    may be used to endorse or promote products derived from this software
15   *    without specific prior written permission.
16   *
17   * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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   *	@(#)kern_time.c	8.1 (Berkeley) 6/10/93
30   */
31  #include <sys/kernel.h>
32  #include <sys/time.h>
33  
34  int
35  ppsratecheck(struct timeval *lasttime, int *curpps, int maxpps)
36  {
37  	int now;
38  
39  	/*
40  	 * Reset the last time and counter if this is the first call
41  	 * or more than a second has passed since the last update of
42  	 * lasttime.
43  	 */
44  	now = ticks;
45  	if (lasttime->tv_sec == 0 || (u_int)(now - lasttime->tv_sec) >= hz) {
46  		lasttime->tv_sec = now;
47  		*curpps = 1;
48  		return (maxpps != 0);
49  	} else {
50  		(*curpps)++;		/* NB: ignore potential overflow */
51  		return (maxpps < 0 || *curpps < maxpps);
52  	}
53  }
54