3 * An UDP connection listener
5 * @author Roland Haeder <webmaster@ship-simu.org>
7 * @copyright Copyright (c) 2007, 2008 Roland Haeder, 2009, 2010 Hub Developer Team
8 * @license GNU GPL 3.0 or any newer version
9 * @link http://www.ship-simu.org
11 * This program is free software: you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation, either version 3 of the License, or
14 * (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program. If not, see <http://www.gnu.org/licenses/>.
24 class UdpListener extends BaseListener implements Listenable {
26 * Protected constructor
30 protected function __construct () {
31 // Call parent constructor
32 parent::__construct(__CLASS__);
36 * Creates an instance of this class
38 * @param $nodeInstance A NodeHelper instance
39 * @return $listenerInstance An instance a prepared listener class
41 public final static function createUdpListener (NodeHelper $nodeInstance) {
43 $listenerInstance = new UdpListener();
45 // Set the application instance
46 $listenerInstance->setNodeInstance($nodeInstance);
48 // Set the protocol to UDP
49 $listenerInstance->setProtocol('udp');
51 // Return the prepared instance
52 return $listenerInstance;
56 * Initializes the listener by setting up the required socket server
59 * @throws InvalidSocketException Thrown if the socket is invalid or an
61 * @todo stream_socket_server() was declared slow by some user comments.
62 * @todo Please rewrite it to socket_create() and its brothers.
64 public function initListener() {
65 // Try to open a UDP socket
66 $socket = stream_socket_server('udp://' . $this->getListenAddress() . ':' . $this->getListenPort(), $errno, $errstr, STREAM_SERVER_BIND);
68 // Is the socket a valid resource or do we have any error?
69 if ((!is_resource($socket)) || ($errno > 0)) {
70 // Then throw an InvalidSocketException
71 throw new InvalidSocketException(array($this, gettype($socket), $errno, $errstr), BaseListener::EXCEPTION_INVALID_SOCKET);
74 // Now, we want non-blocking mode
75 $this->debugOutput('LISTENER: Setting non-blocking mode.');
76 if (!stream_set_blocking($socket, false)) {
77 // Get socket error code for verification
78 $socketError = socket_last_error($socket);
81 $errorMessage = socket_strerror($socketError);
83 // Shutdown this socket
84 $this->shutdownSocket($socket);
87 throw new InvalidSocketException(array($this, gettype($socket), $socketError, $errorMessage), BaseListener::EXCEPTION_INVALID_SOCKET);
90 // Remember the socket in our class
91 $this->registerServerSocketResource($socket);
94 $this->debugOutput('LISTENER: UDP listener now ready on IP ' . $this->getListenAddress() . ', port ' . $this->getListenPort() . ' for service.');
98 * "Listens" for incoming network packages
103 public function doListen() {
104 // Read a package and determine the client
105 $pkt = trim(stream_socket_recvfrom($this->getSocketResource(), 1500, 0, $peer));
107 // Zero sized packages/peer names are usual in non-blocking mode
108 if ((empty($pkt)) || (trim($peer) == '')) {
114 $this->debugOutput('LISTENER: Handling UDP package with size ' . strlen($pkt) . ' from peer ' . $peer);