libcruft-util/time.cpp

131 lines
3.4 KiB
C++

/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* Copyright 2010-2016 Danny Robson <danny@nerdcruft.net>
*/
#include "time.hpp"
#include "log.hpp"
#include <chrono>
using util::delta_clock;
///////////////////////////////////////////////////////////////////////////////
static const uint64_t SECOND = 1'000'000'000UL;
static const uint64_t MILLISECOND = 1'000'000UL;
///////////////////////////////////////////////////////////////////////////////
uintmax_t
util::nanoseconds (void)
{
return std::chrono::duration_cast<
std::chrono::duration<uintmax_t, std::nano>
> (
std::chrono::high_resolution_clock::now ().time_since_epoch ()
).count ();
}
///////////////////////////////////////////////////////////////////////////////
delta_clock::delta_clock ():
time { util::nanoseconds (), util::nanoseconds () }
{ ; }
//-----------------------------------------------------------------------------
std::chrono::nanoseconds
delta_clock::dt (void)
{
time.prev = time.curr;
time.curr = nanoseconds ();
return std::chrono::nanoseconds (time.curr - time.prev);
}
///////////////////////////////////////////////////////////////////////////////
util::period_query::period_query (float seconds)
{
m_time.start = nanoseconds ();
m_time.period = static_cast<uint64_t> (seconds * SECOND);
}
//-----------------------------------------------------------------------------
bool
util::period_query::poll (void)
{
uint64_t now = nanoseconds ();
uint64_t diff = now - m_time.start;
if (diff < m_time.period)
return false;
m_time.start += diff % m_time.period;
return true;
}
///////////////////////////////////////////////////////////////////////////////
util::rate_limiter::rate_limiter (unsigned rate):
m_last (nanoseconds ()),
m_target (SECOND / rate)
{ ; }
//-----------------------------------------------------------------------------
void
util::rate_limiter::poll (void)
{
uint64_t now = nanoseconds ();
uint64_t total = now - m_last;
if (total < m_target)
sleep (m_target - total);
m_last = now;
}
///////////////////////////////////////////////////////////////////////////////
util::polled_duration::polled_duration (std::string name, uint64_t interval):
m_name (name),
m_interval (interval),
m_next (nanoseconds () + interval)
{ ; }
//-----------------------------------------------------------------------------
void
util::polled_duration::start (void)
{
m_last = nanoseconds ();
}
//-----------------------------------------------------------------------------
void
util::polled_duration::stop (void) {
uint64_t now = nanoseconds ();
uint64_t dt = now - m_last;
m_series.add (dt / MILLISECOND);
if (m_next < now) {
LOG_DEBUG ("timing: '%s'. %s", m_name, m_series);
m_series.reset ();
m_next = now + m_interval;
}
}