/****************************************************************************
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** Public License version 3.0 as published by the Free Software Foundation
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****************************************************************************/

#include "qelapsedtimer.h"
#include "qpair.h"
#include <e32std.h>
#include <sys/time.h>
#include <hal.h>

QT_BEGIN_NAMESPACE

// return quint64 to avoid sign-extension
static quint64 getMicrosecondFromTick()
{
    static TInt nanokernel_tick_period;
    if (!nanokernel_tick_period)
        HAL::Get(HAL::ENanoTickPeriod, nanokernel_tick_period);

    static quint32 highdword = 0;
    static quint32 lastval = 0;
    quint32 val = User::NTickCount();
    if (val < lastval)
        ++highdword;
    lastval = val;

    return nanokernel_tick_period * (val | (quint64(highdword) << 32));
}

static quint64 getMillisecondFromTick()
{
    return getMicrosecondFromTick() / 1000;
}

timeval qt_gettime()
{
    timeval tv;
    quint64 now = getMicrosecondFromTick();
    tv.tv_sec = now / 1000000;
    tv.tv_usec = now % 1000000;

    return tv;
}

QElapsedTimer::ClockType QElapsedTimer::clockType()
{
    return TickCounter;
}

bool QElapsedTimer::isMonotonic()
{
    return true;
}

void QElapsedTimer::start()
{
    t1 = getMillisecondFromTick();
    t2 = 0;
}

qint64 QElapsedTimer::restart()
{
    qint64 oldt1 = t1;
    t1 = getMillisecondFromTick();
    t2 = 0;
    return t1 - oldt1;
}

qint64 QElapsedTimer::elapsed() const
{
    return getMillisecondFromTick() - t1;
}

qint64 QElapsedTimer::msecsSinceReference() const
{
    return t1;
}

qint64 QElapsedTimer::msecsTo(const QElapsedTimer &other) const
{
    return other.t1 - t1;
}

qint64 QElapsedTimer::secsTo(const QElapsedTimer &other) const
{
    return msecsTo(other) / 1000;
}

bool operator<(const QElapsedTimer &v1, const QElapsedTimer &v2)
{
    return (v1.t1 - v2.t1) < 0;
}

QT_END_NAMESPACE