<?php
namespace React\EventLoop\Timer;
use React\EventLoop\TimerInterface;
/**
* A scheduler implementation that can hold multiple timer instances
*
* This class should only be used internally, see TimerInterface instead.
*
* @see TimerInterface
* @internal
*/
final class Timers
{
private $time;
private $timers = array();
private $schedule = array();
private $sorted = true;
private $useHighResolution;
public function __construct()
{
// prefer high-resolution timer, available as of PHP 7.3+
$this->useHighResolution = \function_exists('hrtime');
}
public function updateTime()
{
return $this->time = $this->useHighResolution ? \hrtime(true) * 1e-9 : \microtime(true);
}
public function getTime()
{
return $this->time ?: $this->updateTime();
}
public function add(TimerInterface $timer)
{
$id = \spl_object_hash($timer);
$this->timers[$id] = $timer;
$this->schedule[$id] = $timer->getInterval() + $this->updateTime();
$this->sorted = false;
}
public function contains(TimerInterface $timer)
{
return isset($this->timers[\spl_object_hash($timer)]);
}
public function cancel(TimerInterface $timer)
{
$id = \spl_object_hash($timer);
unset($this->timers[$id], $this->schedule[$id]);
}
public function getFirst()
{
// ensure timers are sorted to simply accessing next (first) one
if (!$this->sorted) {
$this->sorted = true;
\asort($this->schedule);
}
return \reset($this->schedule);
}
public function isEmpty()
{
return \count($this->timers) === 0;
}
public function tick()
{
// hot path: skip timers if nothing is scheduled
if (!$this->schedule) {
return;
}
// ensure timers are sorted so we can execute in order
if (!$this->sorted) {
$this->sorted = true;
\asort($this->schedule);
}
$time = $this->updateTime();
foreach ($this->schedule as $id => $scheduled) {
// schedule is ordered, so loop until first timer that is not scheduled for execution now
if ($scheduled >= $time) {
break;
}
// skip any timers that are removed while we process the current schedule
if (!isset($this->schedule[$id]) || $this->schedule[$id] !== $scheduled) {
continue;
}
$timer = $this->timers[$id];
\call_user_func($timer->getCallback(), $timer);
// re-schedule if this is a periodic timer and it has not been cancelled explicitly already
if ($timer->isPeriodic() && isset($this->timers[$id])) {
$this->schedule[$id] = $timer->getInterval() + $time;
$this->sorted = false;
} else {
unset($this->timers[$id], $this->schedule[$id]);
}
}
}
}