PublicUtility/CAHostTimeBase.cpp
/* |
File: CAHostTimeBase.cpp |
Abstract: CAHostTimeBase.h |
Version: 1.01 |
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*/ |
//============================================================================= |
// Includes |
//============================================================================= |
#include "CAHostTimeBase.h" |
Float64 CAHostTimeBase::sFrequency = 0; |
Float64 CAHostTimeBase::sInverseFrequency = 0; |
UInt32 CAHostTimeBase::sMinDelta = 0; |
UInt32 CAHostTimeBase::sToNanosNumerator = 0; |
UInt32 CAHostTimeBase::sToNanosDenominator = 0; |
UInt32 CAHostTimeBase::sFromNanosNumerator = 0; |
UInt32 CAHostTimeBase::sFromNanosDenominator = 0; |
bool CAHostTimeBase::sUseMicroseconds = false; |
bool CAHostTimeBase::sIsInited = false; |
#if Track_Host_TimeBase |
UInt64 CAHostTimeBase::sLastTime = 0; |
#endif |
//============================================================================= |
// CAHostTimeBase |
// |
// This class provides platform independent access to the host's time base. |
//============================================================================= |
void CAHostTimeBase::Initialize() |
{ |
// get the info about Absolute time |
#if TARGET_OS_MAC |
struct mach_timebase_info theTimeBaseInfo; |
mach_timebase_info(&theTimeBaseInfo); |
sMinDelta = 1; |
sToNanosNumerator = theTimeBaseInfo.numer; |
sToNanosDenominator = theTimeBaseInfo.denom; |
sFromNanosNumerator = sToNanosDenominator; |
sFromNanosDenominator = sToNanosNumerator; |
// the frequency of that clock is: (sToNanosDenominator / sToNanosNumerator) * 10^9 |
sFrequency = static_cast<Float64>(sToNanosDenominator) / static_cast<Float64>(sToNanosNumerator); |
sFrequency *= 1000000000.0; |
#elif TARGET_OS_WIN32 |
LARGE_INTEGER theFrequency; |
QueryPerformanceFrequency(&theFrequency); |
sMinDelta = 1; |
sToNanosNumerator = 1000000000ULL; |
sToNanosDenominator = *((UInt64*)&theFrequency); |
sFromNanosNumerator = sToNanosDenominator; |
sFromNanosDenominator = sToNanosNumerator; |
sFrequency = static_cast<Float64>(*((UInt64*)&theFrequency)); |
#endif |
sInverseFrequency = 1.0 / sFrequency; |
#if Log_Host_Time_Base_Parameters |
DebugMessage( "Host Time Base Parameters"); |
DebugMessageN1(" Minimum Delta: %lu", sMinDelta); |
DebugMessageN1(" Frequency: %f", sFrequency); |
DebugMessageN1(" To Nanos Numerator: %lu", sToNanosNumerator); |
DebugMessageN1(" To Nanos Denominator: %lu", sToNanosDenominator); |
DebugMessageN1(" From Nanos Numerator: %lu", sFromNanosNumerator); |
DebugMessageN1(" From Nanos Denominator: %lu", sFromNanosDenominator); |
#endif |
sIsInited = true; |
} |
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