/**
* Workaround for the problem encountered in certains JDKs that a thread listening on a socket
* cannot be interrupted. Therefore we just send a dummy datagram packet so that the thread 'wakes
* up' and realizes it has to terminate. Should be removed when all JDKs support
* Thread.interrupt() on reads. Uses sock t send dummy packet, so this socket has to be still
* alive.
*
* @param dest The destination host. Will be local host if null
* @param port The destination port
*/
void sendDummyPacket(InetAddress dest, int port) {
DatagramPacket packet;
byte[] buf = {0};
if (dest == null) {
try {
dest = InetAddress.getLocalHost();
} catch (Exception e) {
}
}
if (Trace.debug) {
Trace.info("UDP.sendDummyPacket()", "sending packet to " + dest + ":" + port);
}
if (sock == null || dest == null) {
Trace.warn(
"UDP.sendDummyPacket()", "sock was null or dest was null, cannot send dummy packet");
return;
}
packet = new DatagramPacket(buf, buf.length, dest, port);
try {
sock.send(packet);
} catch (Throwable e) {
Trace.error(
"UDP.sendDummyPacket()",
"exception sending dummy packet to " + dest + ":" + port + ": " + e);
}
}
/**
* Create UDP sender and receiver sockets. Currently there are 2 sockets (sending and receiving).
* This is due to Linux's non-BSD compatibility in the JDK port (see DESIGN).
*/
void createSockets() throws Exception {
InetAddress tmp_addr = null;
// bind_addr not set, try to assign one by default. This is needed on Windows
// changed by bela Feb 12 2003: by default multicast sockets will be bound to all network
// interfaces
// CHANGED *BACK* by bela March 13 2003: binding to all interfaces did not result in a correct
// local_addr. As a matter of fact, comparison between e.g. 0.0.0.0:1234 (on hostA) and
// 0.0.0.0:1.2.3.4 (on hostB) would fail !
if (bind_addr == null) {
InetAddress[] interfaces =
InetAddress.getAllByName(InetAddress.getLocalHost().getHostAddress());
if (interfaces != null && interfaces.length > 0) bind_addr = interfaces[0];
}
if (bind_addr == null) bind_addr = InetAddress.getLocalHost();
if (bind_addr != null && Trace.trace) {
Trace.info(
"UDP.createSockets()",
"unicast sockets will use interface " + bind_addr.getHostAddress());
// 2. Create socket for receiving unicast UDP packets. The address and port
// of this socket will be our local address (local_addr)
// 27-6-2003 bgooren, find available port in range (start_port, start_port+port_range)
}
int rcv_port = bind_port, max_port = bind_port + port_range;
while (rcv_port <= max_port) {
try {
sock = new DatagramSocket(rcv_port, bind_addr);
break;
} catch (SocketException bind_ex) { // Cannot listen on this port
rcv_port++;
} catch (SecurityException sec_ex) { // Not allowed to list on this port
rcv_port++;
}
// Cannot listen at all, throw an Exception
if (rcv_port == max_port + 1) { // +1 due to the increment above
throw new Exception(
"UDP.createSockets(): cannot list on any port in range "
+ bind_port
+ "-"
+ (bind_port + port_range));
}
}
// ucast_recv_sock=new DatagramSocket(bind_port, bind_addr);
if (sock == null) {
throw new Exception("UDP.createSocket(): sock is null");
}
local_addr = new IpAddress(sock.getLocalAddress(), sock.getLocalPort());
if (additional_data != null) {
local_addr.setAdditionalData(additional_data);
// 3. Create socket for receiving IP multicast packets
}
if (ip_mcast) {
mcast_sock = new MulticastSocket(mcast_port);
mcast_sock.setTimeToLive(ip_ttl);
if (bind_addr != null) {
mcast_sock.setInterface(bind_addr);
}
tmp_addr = InetAddress.getByName(mcast_addr_name);
mcast_addr = new IpAddress(tmp_addr, mcast_port);
mcast_sock.joinGroup(tmp_addr);
}
setBufferSizes();
if (Trace.trace) {
Trace.info("UDP.createSockets()", "socket information:\n" + dumpSocketInfo());
}
}
/**
* Setup the Protocol instance acording to the configuration string The following properties are
* being read by the UDP protocol param mcast_addr - the multicast address to use default is
* 224.0.0.200 param mcast_port - (int) the port that the multicast is sent on default is 7500
* param ip_mcast - (boolean) flag whether to use IP multicast - default is true param ip_ttl -
* Set the default time-to-live for multicast packets sent out on this socket. default is 32
*
* @return true if no other properties are left. false if the properties still have data in them,
* ie , properties are left over and not handled by the protocol stack
*/
public boolean setProperties(Properties props) {
String str, tmp;
tmp = System.getProperty("UDP.bind_addr");
if (tmp != null) {
str = tmp;
} else {
str = props.getProperty("bind_addr");
}
if (str != null) {
try {
bind_addr = InetAddress.getByName(str);
} catch (UnknownHostException unknown) {
Trace.fatal("UDP.setProperties()", "(bind_addr): host " + str + " not known");
return false;
}
props.remove("bind_addr");
}
str = props.getProperty("bind_port");
if (str != null) {
bind_port = new Integer(str).intValue();
props.remove("bind_port");
}
str = props.getProperty("start_port");
if (str != null) {
bind_port = new Integer(str).intValue();
props.remove("start_port");
}
str = props.getProperty("port_range");
if (str != null) {
port_range = new Integer(str).intValue();
props.remove("port_range");
}
str = props.getProperty("mcast_addr");
if (str != null) {
mcast_addr_name = new String(str);
props.remove("mcast_addr");
}
str = props.getProperty("mcast_port");
if (str != null) {
mcast_port = new Integer(str).intValue();
props.remove("mcast_port");
}
str = props.getProperty("ip_mcast");
if (str != null) {
ip_mcast = new Boolean(str).booleanValue();
props.remove("ip_mcast");
}
str = props.getProperty("ip_ttl");
if (str != null) {
ip_ttl = new Integer(str).intValue();
props.remove("ip_ttl");
}
str = props.getProperty("mcast_send_buf_size");
if (str != null) {
mcast_send_buf_size = Integer.parseInt(str);
props.remove("mcast_send_buf_size");
}
str = props.getProperty("mcast_recv_buf_size");
if (str != null) {
mcast_recv_buf_size = Integer.parseInt(str);
props.remove("mcast_recv_buf_size");
}
str = props.getProperty("ucast_send_buf_size");
if (str != null) {
ucast_send_buf_size = Integer.parseInt(str);
props.remove("ucast_send_buf_size");
}
str = props.getProperty("ucast_recv_buf_size");
if (str != null) {
ucast_recv_buf_size = Integer.parseInt(str);
props.remove("ucast_recv_buf_size");
}
str = props.getProperty("loopback");
if (str != null) {
loopback = new Boolean(str).booleanValue();
props.remove("loopback");
}
// this is deprecated, just left for compatibility (use use_incoming_packet_handler)
str = props.getProperty("use_packet_handler");
if (str != null) {
use_incoming_packet_handler = new Boolean(str).booleanValue();
props.remove("use_packet_handler");
Trace.warn(
"UDP.setProperties()",
"'use_packet_handler' is deprecated; use 'use_incoming_packet_handler' instead");
}
str = props.getProperty("use_incoming_packet_handler");
if (str != null) {
use_incoming_packet_handler = new Boolean(str).booleanValue();
props.remove("use_incoming_packet_handler");
}
str = props.getProperty("use_outgoing_packet_handler");
if (str != null) {
use_outgoing_packet_handler = new Boolean(str).booleanValue();
props.remove("use_outgoing_packet_handler");
}
str = props.getProperty("max_bundle_size");
if (str != null) {
int bundle_size = Integer.parseInt(str);
if (bundle_size > max_bundle_size) {
Trace.error(
"UDP.setProperties()",
"max_bundle_size ("
+ bundle_size
+ ") is greater than largest UDP fragmentation size ("
+ max_bundle_size
+ ")");
return false;
}
if (bundle_size <= 0) {
Trace.error("UDP.setProperties()", "max_bundle_size (" + bundle_size + ") is <= 0");
return false;
}
max_bundle_size = bundle_size;
props.remove("max_bundle_size");
}
str = props.getProperty("max_bundle_timeout");
if (str != null) {
max_bundle_timeout = Long.parseLong(str);
if (max_bundle_timeout <= 0) {
Trace.error(
"UDP.setProperties()", "max_bundle_timeout of " + max_bundle_timeout + " is invalid");
return false;
}
props.remove("max_bundle_timeout");
}
str = props.getProperty("enable_bundling");
if (str != null) {
enable_bundling = new Boolean(str).booleanValue();
props.remove("enable_bundling");
}
if (props.size() > 0) {
System.err.println("UDP.setProperties(): the following properties are not recognized:");
props.list(System.out);
return false;
}
if (enable_bundling) {
if (use_outgoing_packet_handler == false) {
Trace.warn(
"UDP.setProperties()",
"enable_bundling is true; setting use_outgoing_packet_handler=true");
}
use_outgoing_packet_handler = true;
}
return true;
}