Queue::wait

public function wait(?Http\Promise $targetPromise = null): array
{
	$processedPromises = [];

	if (empty($this->promises))
	{
		return $processedPromises;
	}

	do
	{
		$fetchBody = true;

		try
		{
			$status = curl_multi_exec($this->handle, $active);
		}
		catch (SkipBodyException $e)
		{
			$fetchBody = false;
		}

		$info = curl_multi_info_read($this->handle);

		if ($info !== false)
		{
			$promiseId = spl_object_hash($info['handle']);

			$promise = $this->promises[$promiseId];
			$handler = $promise->getHandler();

			if (!$fetchBody)
			{
				// we don't want a body, just fulfil a promise with response headers
				$promise->fulfill($handler->getResponse());
			}
			elseif ($info['result'] === CURLE_OK)
			{
				$response = $handler->getResponse();

				if ($handler->getDebugLevel() & HttpDebug::RESPONSE_BODY)
				{
					$handler->log($response->getBody(), HttpDebug::RESPONSE_BODY);
				}

				// need to ajust the response headers (PSR-18)
				$response->adjustHeaders();

				$promise->fulfill($response);
			}
			else
			{
				$error = curl_error($info['handle']);

				$promise->reject(new Http\NetworkException($promise->getRequest(), $error));

				if ($logger = $handler->getLogger())
				{
					$logger->error($error);
				}
			}

			// job done, the promise is fullfilled or rejected
			$processedPromises[] = $promise;

			$this->delete($promiseId);

			if ($targetPromise && $promiseId === $targetPromise->getId())
			{
				// we were waiting for the specific promise
				return $processedPromises;
			}
		}
	}
	while ($status === CURLM_CALL_MULTI_PERFORM || $active);

	return $processedPromises;
}