libgfasitarautils/src/sucycletimer.cpp

#include <errno.h>
#include "sucycletimer.h"

/////////////////////////////////////////////////////////////////////////////

CCycleTimer::CCycleTimer(unsigned int nMaxCycleIntervalMilliSec1, unsigned int nMaxCycleIntervalMilliSec2, unsigned int nMaxCycleIntervalMilliSec3) :	m_nMaxCycleNanoSec1(nMaxCycleIntervalMilliSec1 * _NSEC_PER_MSEC),
																																						m_nMaxCycleNanoSec2(nMaxCycleIntervalMilliSec2 * _NSEC_PER_MSEC),
																																						m_nMaxCycleNanoSec3(nMaxCycleIntervalMilliSec3 * _NSEC_PER_MSEC)
{
	memset(&m_ts, 0, sizeof(m_ts));
	::clock_getres(CLOCK_MONOTONIC, &m_res);
}

CCycleTimer::CCycleTimer(const struct timespec *pts1, const struct timespec *pts2, const struct timespec *pts3) :	m_nMaxCycleNanoSec1(pts1 ? Timespec2NanoSec(*pts1) : 0),
																													m_nMaxCycleNanoSec2(pts2 ? Timespec2NanoSec(*pts2) : 0),
																													m_nMaxCycleNanoSec3(pts3 ? Timespec2NanoSec(*pts3) : 0)
{
	memset(&m_ts, 0, sizeof(m_ts));
	::clock_getres(CLOCK_MONOTONIC, &m_res);
}

CCycleTimer::~CCycleTimer(void)
{
}

/////////////////////////////////////////////////////////////////////////////

cy_time_t CCycleTimer::GetNanoTick(struct timespec *pts)
{
	struct timespec ts;
	struct timespec &rts = pts ? *pts : ts;
	::clock_gettime(CLOCK_MONOTONIC, &rts);
	return Timespec2NanoSec(rts);
}

cy_time_t CCycleTimer::GetNanoSecElapsed(const struct timespec *ptsComparand) const
{
	struct timespec ts;

	if(!ptsComparand)
	{
		::clock_gettime(CLOCK_MONOTONIC, &ts);
		ptsComparand = &ts;
	}

	return TimespecDiffNanoSec(*ptsComparand, m_ts);
}

int CCycleTimer::Sleep(const cy_time_t &rnMaxCycleNanoSec, bool bResumeOnIntr) const
{
	cy_time_t nIntv;
	struct timespec ts, rem;

	::clock_gettime(CLOCK_MONOTONIC, &ts);

	if((nIntv = rnMaxCycleNanoSec - GetNanoSecElapsed(&ts)) > 0)
	{
		int nRet;
		NanoSec2Timespec(nIntv, ts);

		if((nRet = ::clock_nanosleep(CLOCK_MONOTONIC, 0, &ts, &rem)))
		{
			if(bResumeOnIntr)
			{
				while(nRet == EINTR)
				{
					nRet = ::clock_nanosleep(CLOCK_MONOTONIC, 0, &rem, &rem);
				}
			}
		}

		return nRet;
	}

	return 0;
}

void CCycleTimer::TimespecAddSubNanoSec(struct timespec &rts, cy_time_t nNanoSec)
{
	cy_time_t n = Timespec2NanoSec(rts) + nNanoSec;
	NanoSec2Timespec(n, rts);
}