jsloop.php

<?php

$timers = [];
$futureTicks = [];

function setTimeout($callback, $delay)
{
    global $timers;
    $delay = $delay === 0 ? 1 : $delay;
    $timers[] = [
        'type' => 'timeout',
        'time' => hrtime(true) + ($delay * 1000000),
        'callback' => $callback,
        'happend' => false
    ];
    return array_key_last($timers);
}

function setInterval($callback, $delay)
{
    global $timers;
    $delay = $delay === 0 ? 1 : $delay;
    $timers[] = [
        'type' => 'interval',
        'delay' => ($delay * 1000000),
        'time' => hrtime(true) + ($delay * 1000000),
        'callback' => $callback,
        'happend' => false // never change
    ];
    return array_key_last($timers);
}


function setImmediate($callback)
{
    global $futureTicks;
    $futureTicks[] = [
        'callback' => $callback
    ];
}

function clearTimeout($id)
{
    global $timers;
    unset($timers[$id]);
}

function clearInterval($id)
{
    global $timers;
    unset($timers[$id]);
}

// **** USAGE **** 

function exactDelay()
{
    $id = setTimeout(function () use (&$id) {
        exactDelay();
        echo 'exact' . PHP_EOL;
        clearTimeout($id);
    }, 0);
}

setImmediate(function () {
    echo 'immediate' . PHP_EOL;
});

$timeout1 = setTimeout(function () {
    echo 'timeout' . PHP_EOL;
}, 3000);

$interval1 = setInterval(function () {
    echo 'interval' . PHP_EOL;
}, 2000);

setTimeout(function () use ($interval1) {
    clearInterval($interval1);
}, 8100);

exactDelay();

while (true) {
    $currentTime = hrtime(true);
    $delayNextLoop = null;
    foreach ($timers as $key => &$timer) {
        if ($timer['happend'] === false) {
            if ($delayNextLoop === null) {
                $delayNextLoop = $timer['time'] - $currentTime < 0 ? 0 : $timer['time'] - $currentTime;
            }
            $delayNextLoop = ($timer['time'] - $currentTime) < $delayNextLoop ? (($timer['time'] - $currentTime) < 0 ? 0 : $timer['time'] - $currentTime) : $delayNextLoop;
        }

        if ($timer['time'] <= hrtime(true) && $timer['happend'] === false) {
            switch ($timer['type']) {
                case 'interval':
                    $timer['time'] = hrtime(true) + $timer['delay'];
                    call_user_func($timer['callback']);
                    break;
                case 'timeout':
                    $timer['happend'] = true;
                    call_user_func($timer['callback']);
                    break;
            }
        }
    }

    foreach ($futureTicks as $key => &$future) {
        call_user_func($future['callback']);
        unset($futureTicks[$key]);
    }

    $second = $delayNextLoop > 999999999 ? (round($delayNextLoop / 1000000000) == 0 ? 1 : round($delayNextLoop / 1000000000)) : 0;
    $nanoSecond = $delayNextLoop > 999999999 ? 0 : $delayNextLoop;
    time_nanosleep($second, $nanoSecond);
}