// hrtimer.cpp - originally written and placed in the public domain by Wei Dai



#include "pch.h"

#include "hrtimer.h"

#include "misc.h"



#include <stddef.h>		// for NULL

#include <time.h>



#if defined(CRYPTOPP_WIN32_AVAILABLE)

#define WIN32_LEAN_AND_MEAN

#include <windows.h>

# if ((WINVER >= 0x0602 /*_WIN32_WINNT_WIN8*/) || (_WIN32_WINNT >= 0x0602 /*_WIN32_WINNT_WIN8*/))

# include <processthreadsapi.h>

# if defined(WINAPI_FAMILY)

#  if (WINAPI_FAMILY_PARTITION(WINAPI_FAMILY_PHONE_APP))

#   include <profileapi.h>

#  endif

# endif

#endif

#endif



#if defined(CRYPTOPP_UNIX_AVAILABLE)

#include <sys/time.h>

#include <sys/times.h>

#include <unistd.h>

#endif



#include "trap.h"



NAMESPACE_BEGIN(CryptoPP)



#if defined(CRYPTOPP_WIN32_AVAILABLE)

static TimerWord InitializePerformanceCounterFrequency()

{

	LARGE_INTEGER freq = {0,0};

	if (!QueryPerformanceFrequency(&freq))

		throw Exception(Exception::OTHER_ERROR, "Timer: QueryPerformanceFrequency failed with error " + IntToString(GetLastError()));

	return freq.QuadPart;

}



inline TimerWord PerformanceCounterFrequency()

{

	static const word64 freq = InitializePerformanceCounterFrequency();

	return freq;

}

#endif



#ifndef CRYPTOPP_IMPORTS



double TimerBase::ConvertTo(TimerWord t, Unit unit)

{

	static unsigned long unitsPerSecondTable[] = {1, 1000, 1000*1000, 1000*1000*1000};



	// When 'unit' is an enum 'Unit', a Clang warning is generated.

	CRYPTOPP_ASSERT(static_cast<unsigned int>(unit) < COUNTOF(unitsPerSecondTable));

	return static_cast<double>(t) * unitsPerSecondTable[unit] / TicksPerSecond();

}



void TimerBase::StartTimer()

{

	m_last = m_start = GetCurrentTimerValue();

	m_started = true;

}



double TimerBase::ElapsedTimeAsDouble()

{

	if (m_stuckAtZero)

		return 0;



	if (m_started)

	{

		TimerWord now = GetCurrentTimerValue();

		if (m_last < now)	// protect against OS bugs where time goes backwards

			m_last = now;

		return ConvertTo(m_last - m_start, m_timerUnit);

	}



	StartTimer();

	return 0;

}



unsigned long TimerBase::ElapsedTime()

{

	double elapsed = ElapsedTimeAsDouble();

	CRYPTOPP_ASSERT(elapsed <= (double)ULONG_MAX);

	return (unsigned long)elapsed;

}



TimerWord Timer::GetCurrentTimerValue()

{

#if defined(CRYPTOPP_WIN32_AVAILABLE)

	// Use the first union member to avoid an uninitialized warning

	LARGE_INTEGER now = {0,0};

	if (!QueryPerformanceCounter(&now))

		throw Exception(Exception::OTHER_ERROR, "Timer: QueryPerformanceCounter failed with error " + IntToString(GetLastError()));

	return now.QuadPart;

#elif defined(CRYPTOPP_UNIX_AVAILABLE)

	timeval now;

	gettimeofday(&now, NULLPTR);

	return (TimerWord)now.tv_sec * 1000000 + now.tv_usec;

#else

	// clock_t now;

	return clock();

#endif

}



TimerWord Timer::TicksPerSecond()

{

#if defined(CRYPTOPP_WIN32_AVAILABLE)

	return PerformanceCounterFrequency();

#elif defined(CRYPTOPP_UNIX_AVAILABLE)

	return 1000000;

#else

	return CLOCKS_PER_SEC;

#endif

}



#endif	// #ifndef CRYPTOPP_IMPORTS



TimerWord ThreadUserTimer::GetCurrentTimerValue()

{

#if defined(CRYPTOPP_WIN32_AVAILABLE) && defined(THREAD_TIMER_AVAILABLE)

	static bool getCurrentThreadImplemented = true;

	if (getCurrentThreadImplemented)

	{

		FILETIME now, ignored;

		if (!GetThreadTimes(GetCurrentThread(), &ignored, &ignored, &ignored, &now))

		{

			const DWORD lastError = GetLastError();

			if (lastError == ERROR_CALL_NOT_IMPLEMENTED)

			{

				getCurrentThreadImplemented = false;

				goto GetCurrentThreadNotImplemented;

			}

			throw Exception(Exception::OTHER_ERROR, "ThreadUserTimer: GetThreadTimes failed with error " + IntToString(lastError));

		}

		return now.dwLowDateTime + ((TimerWord)now.dwHighDateTime << 32);

	}

GetCurrentThreadNotImplemented:

	return (TimerWord)clock() * (10*1000*1000 / CLOCKS_PER_SEC);

#elif defined(CRYPTOPP_WIN32_AVAILABLE) && !defined(THREAD_TIMER_AVAILABLE)

	LARGE_INTEGER now;

	if (!QueryPerformanceCounter(&now))

	{

		const DWORD lastError = GetLastError();

		throw Exception(Exception::OTHER_ERROR, "ThreadUserTimer: QueryPerformanceCounter failed with error " + IntToString(lastError));

	}

	return now.QuadPart;

#elif defined(CRYPTOPP_UNIX_AVAILABLE)

	tms now;

	times(&now);

	return now.tms_utime;

#else

	return clock();

#endif

}



TimerWord ThreadUserTimer::TicksPerSecond()

{

#if defined(CRYPTOPP_WIN32_AVAILABLE) && defined(THREAD_TIMER_AVAILABLE)

	return 10*1000*1000;

#elif defined(CRYPTOPP_WIN32_AVAILABLE) && !defined(THREAD_TIMER_AVAILABLE)

	static const TimerWord ticksPerSecond = PerformanceCounterFrequency();

	return ticksPerSecond;

#elif defined(CRYPTOPP_UNIX_AVAILABLE)

	static const long ticksPerSecond = sysconf(_SC_CLK_TCK);

	return ticksPerSecond;

#else

	return CLOCKS_PER_SEC;

#endif

}



NAMESPACE_END