<?php
namespace React\Promise\Timer;
use React\Promise\CancellablePromiseInterface;
use React\EventLoop\LoopInterface;
use React\Promise\PromiseInterface;
use React\Promise\Promise;
function timeout(PromiseInterface $promise, $time, LoopInterface $loop)
{
// cancelling this promise will only try to cancel the input promise,
// thus leaving responsibility to the input promise.
$canceller = null;
if ($promise instanceof CancellablePromiseInterface) {
// pass promise by reference to clean reference after cancellation handler
// has been invoked once in order to avoid garbage references in call stack.
$canceller = function () use (&$promise) {
$promise->cancel();
$promise = null;
};
}
return new Promise(function ($resolve, $reject) use ($loop, $time, $promise) {
$timer = null;
$promise = $promise->then(function ($v) use (&$timer, $loop, $resolve) {
if ($timer) {
$loop->cancelTimer($timer);
}
$timer = false;
$resolve($v);
}, function ($v) use (&$timer, $loop, $reject) {
if ($timer) {
$loop->cancelTimer($timer);
}
$timer = false;
$reject($v);
});
// promise already resolved => no need to start timer
if ($timer === false) {
return;
}
// start timeout timer which will cancel the input promise
$timer = $loop->addTimer($time, function () use ($time, &$promise, $reject) {
$reject(new TimeoutException($time, 'Timed out after ' . $time . ' seconds'));
// try to invoke cancellation handler of input promise and then clean
// reference in order to avoid garbage references in call stack.
if ($promise instanceof CancellablePromiseInterface) {
$promise->cancel();
}
$promise = null;
});
}, $canceller);
}
function resolve($time, LoopInterface $loop)
{
return new Promise(function ($resolve) use ($loop, $time, &$timer) {
// resolve the promise when the timer fires in $time seconds
$timer = $loop->addTimer($time, function () use ($time, $resolve) {
$resolve($time);
});
}, function () use (&$timer, $loop) {
// cancelling this promise will cancel the timer, clean the reference
// in order to avoid garbage references in call stack and then reject.
$loop->cancelTimer($timer);
$timer = null;
throw new \RuntimeException('Timer cancelled');
});
}
function reject($time, LoopInterface $loop)
{
return resolve($time, $loop)->then(function ($time) {
throw new TimeoutException($time, 'Timer expired after ' . $time . ' seconds');
});
}
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