Hprose\Swoole\Socket\Transporter::setReceiveEvent PHP Method

    public function setReceiveEvent($conn)
    {
        $bytes = '';
        $headerLength = 4;
        $dataLength = -1;
        $id = null;
        $conn->on('receive', function ($conn, $chunk) use(&$bytes, &$headerLength, &$dataLength, &$id) {
            $bytes .= $chunk;
            while (true) {
                $length = strlen($bytes);
                if ($dataLength < 0 && $length >= $headerLength) {
                    list(, $dataLength) = unpack('N', substr($bytes, 0, 4));
                    if (($dataLength & 0x80000000) !== 0) {
                        $dataLength &= 0x7fffffff;
                        $headerLength = 8;
                    }
                }
                if ($headerLength === 8 && $id === null && $length >= $headerLength) {
                    list(, $id) = unpack('N', substr($bytes, 4, 4));
                }
                if ($dataLength >= 0 && $length - $headerLength >= $dataLength) {
                    $onreceive = $conn->onreceive;
                    $onreceive($conn, substr($bytes, $headerLength, $dataLength), $id);
                    $bytes = substr($bytes, $headerLength + $dataLength);
                    $id = null;
                    $headerLength = 4;
                    $dataLength = -1;
                } else {
                    break;
                }
            }
        });
    }