usr.sbin/dntpd/convert.c

   1 /*
   2  * Copyright (c) 2005 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   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  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/usr.sbin/dntpd/convert.c,v 1.4 2005/04/25 17:42:49 dillon Exp $
  35  */
  36
  37 #include "defs.h"
  38
  39 void
  40 l_fixedpt_to_tv(struct l_fixedpt *fixed, struct timeval *tvp)
  41 {
  42     tvp->tv_sec = fixed->int_partl - JAN_1970;
  43     tvp->tv_usec = (long)((double)fixed->fractionl * 1000000.0 / UINT_MAX);
  44 }
  45
  46 /*
  47  * Subtract usec from tvp, storing the result in tvp.
  48  */
  49 void
  50 tv_subtract_micro(struct timeval *tvp, long usec)
  51 {
  52     if (usec < 0) {
  53         tv_add_micro(tvp, -usec);
  54     } else {
  55         tvp->tv_usec -= usec;
  56         if (tvp->tv_usec < 0) {
  57             tvp->tv_sec -= (-tvp->tv_usec + 999999) / 1000000;
  58             tvp->tv_usec = 1000000 - (-tvp->tv_usec % 1000000);
  59         }
  60     }
  61 }
  62
  63 /*
  64  * Add usec to tvp, storing the result in tvp.
  65  */
  66 void
  67 tv_add_micro(struct timeval *tvp, long usec)
  68 {
  69     if (usec < 0) {
  70         tv_subtract_micro(tvp, -usec);
  71     } else {
  72         tvp->tv_usec += usec;
  73         if (tvp->tv_usec >= 1000000) {
  74             tvp->tv_sec += tvp->tv_usec / 1000000;
  75             tvp->tv_usec = tvp->tv_usec % 1000000;
  76         }
  77     }
  78 }
  79
  80 /*
  81  * Add the fp offset to tvp.
  82  */
  83 void
  84 tv_add_offset(struct timeval *tvp, double offset)
  85 {
  86     tvp->tv_sec += (long)offset;
  87     offset -= (double)(long)offset; /* e.g. -1.3 - (-1) = -0.3 */
  88     tv_add_micro(tvp, (int)(offset * 1000000.0));
  89 }
  90
  91 /*
  92  * Return the time differential in microseconds.
  93  */
  94 double
  95 tv_delta_double(struct timeval *tv1, struct timeval *tv2)
  96 {
  97     double usec;
  98
  99     usec = (double)(tv2->tv_sec - tv1->tv_sec) +
 100                 (double)(tv2->tv_usec - tv1->tv_usec) / 1000000.0;
 101     return(usec);
 102 }
 103
 104 void
 105 tv_to_ts(struct timeval *tv, struct timespec *ts)
 106 {
 107     ts->tv_sec = tv->tv_sec;
 108     ts->tv_nsec = tv->tv_usec * 1000;
 109 }
 110
 111 void
 112 ts_to_tv(struct timespec *ts, struct timeval *tv)
 113 {
 114     tv->tv_sec = ts->tv_sec;
 115     tv->tv_usec = ts->tv_nsec / 1000;
 116 }
 117