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   _PR_MD_INTERVAL_INIT();
  24 #ifdef DEBUG
  25   {
  26     PRIntervalTime ticksPerSec = PR_TicksPerSecond();
  27
  28     PR_ASSERT(ticksPerSec >= PR_INTERVAL_MIN);
  29     PR_ASSERT(ticksPerSec <= PR_INTERVAL_MAX);
  30   }
  31 #endif /* DEBUG */
  32 }
  33
  34 PR_IMPLEMENT(PRIntervalTime) PR_IntervalNow(void) {
  35   if (!_pr_initialized) {
  36     _PR_ImplicitInitialization();
  37   }
  38   return _PR_MD_GET_INTERVAL();
  39 } /* PR_IntervalNow */
  40
  41 PR_EXTERN(PRUint32) PR_TicksPerSecond(void) {
  42   if (!_pr_initialized) {
  43     _PR_ImplicitInitialization();
  44   }
  45   return _PR_MD_INTERVAL_PER_SEC();
  46 } /* PR_TicksPerSecond */
  47
  48 PR_IMPLEMENT(PRIntervalTime) PR_SecondsToInterval(PRUint32 seconds) {
  49   return seconds * PR_TicksPerSecond();
  50 } /* PR_SecondsToInterval */
  51
  52 PR_IMPLEMENT(PRIntervalTime) PR_MillisecondsToInterval(PRUint32 milli) {
  53   PRIntervalTime ticks;
  54   PRUint64 tock, tps, msecPerSec, rounding;
  55   LL_UI2L(tock, milli);
  56   LL_I2L(msecPerSec, PR_MSEC_PER_SEC);
  57   LL_I2L(rounding, (PR_MSEC_PER_SEC >> 1));
  58   LL_I2L(tps, PR_TicksPerSecond());
  59   LL_MUL(tock, tock, tps);
  60   LL_ADD(tock, tock, rounding);
  61   LL_DIV(tock, tock, msecPerSec);
  62   LL_L2UI(ticks, tock);
  63   return ticks;
  64 } /* PR_MillisecondsToInterval */
  65
  66 PR_IMPLEMENT(PRIntervalTime) PR_MicrosecondsToInterval(PRUint32 micro) {
  67   PRIntervalTime ticks;
  68   PRUint64 tock, tps, usecPerSec, rounding;
  69   LL_UI2L(tock, micro);
  70   LL_I2L(usecPerSec, PR_USEC_PER_SEC);
  71   LL_I2L(rounding, (PR_USEC_PER_SEC >> 1));
  72   LL_I2L(tps, PR_TicksPerSecond());
  73   LL_MUL(tock, tock, tps);
  74   LL_ADD(tock, tock, rounding);
  75   LL_DIV(tock, tock, usecPerSec);
  76   LL_L2UI(ticks, tock);
  77   return ticks;
  78 } /* PR_MicrosecondsToInterval */
  79
  80 PR_IMPLEMENT(PRUint32) PR_IntervalToSeconds(PRIntervalTime ticks) {
  81   return ticks / PR_TicksPerSecond();
  82 } /* PR_IntervalToSeconds */
  83
  84 PR_IMPLEMENT(PRUint32) PR_IntervalToMilliseconds(PRIntervalTime ticks) {
  85   PRUint32 milli;
  86   PRUint64 tock, tps, msecPerSec, rounding;
  87   LL_UI2L(tock, ticks);
  88   LL_I2L(msecPerSec, PR_MSEC_PER_SEC);
  89   LL_I2L(tps, PR_TicksPerSecond());
  90   LL_USHR(rounding, tps, 1);
  91   LL_MUL(tock, tock, msecPerSec);
  92   LL_ADD(tock, tock, rounding);
  93   LL_DIV(tock, tock, tps);
  94   LL_L2UI(milli, tock);
  95   return milli;
  96 } /* PR_IntervalToMilliseconds */
  97
  98 PR_IMPLEMENT(PRUint32) PR_IntervalToMicroseconds(PRIntervalTime ticks) {
  99   PRUint32 micro;
 100   PRUint64 tock, tps, usecPerSec, rounding;
 101   LL_UI2L(tock, ticks);
 102   LL_I2L(usecPerSec, PR_USEC_PER_SEC);
 103   LL_I2L(tps, PR_TicksPerSecond());
 104   LL_USHR(rounding, tps, 1);
 105   LL_MUL(tock, tock, usecPerSec);
 106   LL_ADD(tock, tock, rounding);
 107   LL_DIV(tock, tock, tps);
 108   LL_L2UI(micro, tock);
 109   return micro;
 110 } /* PR_IntervalToMicroseconds */
 111
 112 /* prinrval.c */