hrtimer.h

#ifndef CRYPTOPP_HRTIMER_H
#define CRYPTOPP_HRTIMER_H

#include "config.h"

NAMESPACE_BEGIN(CryptoPP)

#ifdef WORD64_AVAILABLE
        typedef word64 TimerWord;
#else
        typedef word32 TimerWord;
#endif

//! _
class TimerBase
{
public:
        enum Unit {SECONDS = 0, MILLISECONDS, MICROSECONDS, NANOSECONDS};
        TimerBase(Unit unit, bool stuckAtZero)  : m_timerUnit(unit), m_stuckAtZero(stuckAtZero), m_started(false) {}

        virtual TimerWord GetCurrentTimerValue() =0;    // GetCurrentTime is a macro in MSVC 6.0
        virtual TimerWord TicksPerSecond() =0;  // this is not the resolution, just a conversion factor into seconds

        void StartTimer();
        double ElapsedTimeAsDouble();
        unsigned long ElapsedTime();

private:
        double ConvertTo(TimerWord t, Unit unit);

        Unit m_timerUnit;       // HPUX workaround: m_unit is a system macro on HPUX
        bool m_stuckAtZero, m_started;
        TimerWord m_start, m_last;
};

//! measure CPU time spent executing instructions of this thread (if supported by OS)
/*! /note This only works correctly on Windows NT or later. On Unix it reports process time, and others wall clock time.
*/
class ThreadUserTimer : public TimerBase
{
public:
        ThreadUserTimer(Unit unit = TimerBase::SECONDS, bool stuckAtZero = false)       : TimerBase(unit, stuckAtZero) {}
        TimerWord GetCurrentTimerValue();
        TimerWord TicksPerSecond();
};

#ifdef HIGHRES_TIMER_AVAILABLE

//! high resolution timer
class Timer : public TimerBase
{
public:
        Timer(Unit unit = TimerBase::SECONDS, bool stuckAtZero = false) : TimerBase(unit, stuckAtZero) {}
        TimerWord GetCurrentTimerValue();
        TimerWord TicksPerSecond();
};

#endif  // HIGHRES_TIMER_AVAILABLE

NAMESPACE_END

#endif

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