nsprpub/pr/src/misc/prinrval.c

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 /*
   7  * file:            prinrval.c
   8  * description:     implementation for the kernel interval timing functions
   9  */
  10
  11 #include "primpl.h"
  12
  13 /*
  14  *-----------------------------------------------------------------------
  15  *
  16  * _PR_InitClock --
  17  *
  18  *
  19  *-----------------------------------------------------------------------
  20  */
  21
  22 void _PR_InitClock(void)
  23 {
  24     _PR_MD_INTERVAL_INIT();
  25 #ifdef DEBUG
  26     {
  27         PRIntervalTime ticksPerSec = PR_TicksPerSecond();
  28
  29         PR_ASSERT(ticksPerSec >= PR_INTERVAL_MIN);
  30         PR_ASSERT(ticksPerSec <= PR_INTERVAL_MAX);
  31     }
  32 #endif /* DEBUG */
  33 }
  34
  35 PR_IMPLEMENT(PRIntervalTime) PR_IntervalNow(void)
  36 {
  37     if (!_pr_initialized) {
  38         _PR_ImplicitInitialization();
  39     }
  40     return _PR_MD_GET_INTERVAL();
  41 }  /* PR_IntervalNow */
  42
  43 PR_EXTERN(PRUint32) PR_TicksPerSecond(void)
  44 {
  45     if (!_pr_initialized) {
  46         _PR_ImplicitInitialization();
  47     }
  48     return _PR_MD_INTERVAL_PER_SEC();
  49 }  /* PR_TicksPerSecond */
  50
  51 PR_IMPLEMENT(PRIntervalTime) PR_SecondsToInterval(PRUint32 seconds)
  52 {
  53     return seconds * PR_TicksPerSecond();
  54 }  /* PR_SecondsToInterval */
  55
  56 PR_IMPLEMENT(PRIntervalTime) PR_MillisecondsToInterval(PRUint32 milli)
  57 {
  58     PRIntervalTime ticks;
  59     PRUint64 tock, tps, msecPerSec, rounding;
  60     LL_UI2L(tock, milli);
  61     LL_I2L(msecPerSec, PR_MSEC_PER_SEC);
  62     LL_I2L(rounding, (PR_MSEC_PER_SEC >> 1));
  63     LL_I2L(tps, PR_TicksPerSecond());
  64     LL_MUL(tock, tock, tps);
  65     LL_ADD(tock, tock, rounding);
  66     LL_DIV(tock, tock, msecPerSec);
  67     LL_L2UI(ticks, tock);
  68     return ticks;
  69 }  /* PR_MillisecondsToInterval */
  70
  71 PR_IMPLEMENT(PRIntervalTime) PR_MicrosecondsToInterval(PRUint32 micro)
  72 {
  73     PRIntervalTime ticks;
  74     PRUint64 tock, tps, usecPerSec, rounding;
  75     LL_UI2L(tock, micro);
  76     LL_I2L(usecPerSec, PR_USEC_PER_SEC);
  77     LL_I2L(rounding, (PR_USEC_PER_SEC >> 1));
  78     LL_I2L(tps, PR_TicksPerSecond());
  79     LL_MUL(tock, tock, tps);
  80     LL_ADD(tock, tock, rounding);
  81     LL_DIV(tock, tock, usecPerSec);
  82     LL_L2UI(ticks, tock);
  83     return ticks;
  84 }  /* PR_MicrosecondsToInterval */
  85
  86 PR_IMPLEMENT(PRUint32) PR_IntervalToSeconds(PRIntervalTime ticks)
  87 {
  88     return ticks / PR_TicksPerSecond();
  89 }  /* PR_IntervalToSeconds */
  90
  91 PR_IMPLEMENT(PRUint32) PR_IntervalToMilliseconds(PRIntervalTime ticks)
  92 {
  93     PRUint32 milli;
  94     PRUint64 tock, tps, msecPerSec, rounding;
  95     LL_UI2L(tock, ticks);
  96     LL_I2L(msecPerSec, PR_MSEC_PER_SEC);
  97     LL_I2L(tps, PR_TicksPerSecond());
  98     LL_USHR(rounding, tps, 1);
  99     LL_MUL(tock, tock, msecPerSec);
 100     LL_ADD(tock, tock, rounding);
 101     LL_DIV(tock, tock, tps);
 102     LL_L2UI(milli, tock);
 103     return milli;
 104 }  /* PR_IntervalToMilliseconds */
 105
 106 PR_IMPLEMENT(PRUint32) PR_IntervalToMicroseconds(PRIntervalTime ticks)
 107 {
 108     PRUint32 micro;
 109     PRUint64 tock, tps, usecPerSec, rounding;
 110     LL_UI2L(tock, ticks);
 111     LL_I2L(usecPerSec, PR_USEC_PER_SEC);
 112     LL_I2L(tps, PR_TicksPerSecond());
 113     LL_USHR(rounding, tps, 1);
 114     LL_MUL(tock, tock, usecPerSec);
 115     LL_ADD(tock, tock, rounding);
 116     LL_DIV(tock, tock, tps);
 117     LL_L2UI(micro, tock);
 118     return micro;
 119 }  /* PR_IntervalToMicroseconds */
 120
 121 /* prinrval.c */
 122