darwin/MKGetTimeBaseInfo.c

   1 /*
   2  * Copyright (c) 2007 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 #include <mach/kern_return.h>
  25 #include <mach/mach_time.h>
  26 #include <stdint.h>
  27
  28 extern void spin_lock(int *);
  29 extern void spin_unlock(int *);
  30
  31 /* deprecated function stub */
  32 kern_return_t
  33 MKGetTimeBaseInfo(
  34     uint32_t *minAbsoluteTimeDelta,
  35     uint32_t *theAbsoluteTimeToNanosecondNumerator,
  36     uint32_t *theAbsoluteTimeToNanosecondDenominator,
  37     uint32_t *theProcessorToAbsoluteTimeNumerator,
  38     uint32_t *theProcessorToAbsoluteTimeDenominator
  39 ) {
  40     static struct mach_timebase_info mti = {0};
  41     static int MKGetTimeBaseInfo_spin_lock = 0;
  42
  43     if(mti.numer == 0) {
  44         kern_return_t err;
  45         spin_lock(&MKGetTimeBaseInfo_spin_lock);
  46         err = mach_timebase_info(&mti);
  47         spin_unlock(&MKGetTimeBaseInfo_spin_lock);
  48         if(err != KERN_SUCCESS)
  49             return err;
  50     }
  51     if(theAbsoluteTimeToNanosecondNumerator)
  52         *theAbsoluteTimeToNanosecondNumerator = mti.numer;
  53     if(theAbsoluteTimeToNanosecondDenominator)
  54         *theAbsoluteTimeToNanosecondDenominator = mti.denom;
  55     if(minAbsoluteTimeDelta)
  56         *minAbsoluteTimeDelta = 1;
  57     if(theProcessorToAbsoluteTimeNumerator)
  58         *theProcessorToAbsoluteTimeNumerator = 1;
  59     if(theProcessorToAbsoluteTimeDenominator)
  60         *theProcessorToAbsoluteTimeDenominator = 1;
  61     return KERN_SUCCESS;
  62 }