/**
* Processes a packet read from either the multicast or unicast socket. Needs to be synchronized
* because mcast or unicast socket reads can be concurrent
*/
void handleIncomingUdpPacket(byte[] data) {
ByteArrayInputStream inp_stream;
ObjectInputStream inp;
Message msg = null;
List l; // used if bundling is enabled
try {
// skip the first n bytes (default: 4), this is the version info
inp_stream = new ByteArrayInputStream(data, VERSION_LENGTH, data.length - VERSION_LENGTH);
inp = new ObjectInputStream(inp_stream);
if (enable_bundling) {
l = new List();
l.readExternal(inp);
for (Enumeration en = l.elements(); en.hasMoreElements(); ) {
msg = (Message) en.nextElement();
try {
handleMessage(msg);
} catch (Throwable t) {
Trace.error("UDP.handleIncomingUdpPacket()", "failure: " + t.toString());
}
}
} else {
msg = new Message();
msg.readExternal(inp);
handleMessage(msg);
}
} catch (Throwable e) {
Trace.error("UDP.handleIncomingUdpPacket()", "exception=" + Trace.getStackTrace(e));
}
}
/**
* 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);
}
}
public void run() {
Event evt;
while (evt_thread != null && event_queue != null) {
try {
evt = (Event) event_queue.remove();
switch (evt.getType()) {
case Event.SUSPECT:
impl.suspect((Address) evt.getArg());
break;
case Event.MERGE:
impl.merge((Vector) evt.getArg());
break;
default:
Trace.error(
"GMS.run()",
"event handler thread encountered event of type "
+ Event.type2String(evt.getType())
+ ": not handled by me !");
break;
}
} catch (QueueClosedException closed) {
break;
} catch (Exception ex) {
Trace.warn("GMS.run()", "exception=" + ex);
}
}
}
/**
* <b>Callback</b>. Called by superclass when event may be handled.
*
* <p><b>Do not use <code>PassDown</code> in this method as the event is passed down by default by
* the superclass after this method returns !</b>
*
* @return boolean Defaults to true. If false, event will not be passed down the stack.
*/
public boolean handleDownEvent(Event evt) {
switch (evt.getType()) {
case Event.CONNECT:
passDown(evt);
try {
group_addr = (String) evt.getArg();
} catch (ClassCastException cce) {
Trace.error(
"GMS.handleDownEvent(CONNECT)",
"group address must " + "be a string (group name) to make sense");
}
impl.join(local_addr);
passUp(new Event(Event.CONNECT_OK));
startEventHandlerThread();
return false; // don't pass down: was already passed down
case Event.DISCONNECT:
impl.leave((Address) evt.getArg());
passUp(new Event(Event.DISCONNECT_OK));
stopEventHandlerThread();
initState();
return true; // pass down
}
return impl.handleDownEvent(evt);
}
void handleMessage(Message msg) {
Event evt;
UdpHeader hdr;
// discard my own multicast loopback copy
if (loopback) {
Address dst = msg.getDest();
Address src = msg.getSrc();
if (dst != null && dst.isMulticastAddress() && src != null && local_addr.equals(src)) {
if (Trace.debug) {
Trace.info("UDP.handleMessage()", "discarded own loopback multicast packet");
}
return;
}
}
evt = new Event(Event.MSG, msg);
if (Trace.debug) {
Trace.info("UDP.handleMessage()", "message is " + msg + ", headers are " + msg.getHeaders());
/* Because Protocol.up() is never called by this bottommost layer, we call up() directly in the observer.
* This allows e.g. PerfObserver to get the time of reception of a message */
}
if (observer != null) {
observer.up(evt, up_queue.size());
}
hdr = (UdpHeader) msg.removeHeader(name);
if (hdr != null) {
/* Discard all messages destined for a channel with a different name */
String ch_name = null;
if (hdr.group_addr != null) {
ch_name = hdr.group_addr;
// Discard if message's group name is not the same as our group name unless the
// message is a diagnosis message (special group name DIAG_GROUP)
}
if (ch_name != null
&& group_addr != null
&& !group_addr.equals(ch_name)
&& !ch_name.equals(Util.DIAG_GROUP)) {
if (Trace.trace) {
Trace.warn(
"UDP.handleMessage()",
"discarded message from different group ("
+ ch_name
+ "). Sender was "
+ msg.getSrc());
}
return;
}
} else {
Trace.error("UDP.handleMessage()", "message does not have a UDP header");
}
passUp(evt);
}
/** Send a message to the address specified in msg.dest */
private void sendUnicastMessage(Message msg) {
IpAddress dest;
Message copy;
Object hdr;
Event evt;
dest = (IpAddress) msg.getDest(); // guaranteed not to be null
if (!(dest instanceof IpAddress)) {
Trace.error("TCP.sendUnicastMessage()", "destination address is not of type IpAddress !");
return;
}
setSourceAddress(msg);
/* Don't send if destination is local address. Instead, switch dst and src and put in up_queue */
if (loopback && local_addr != null && dest != null && dest.equals(local_addr)) {
copy = msg.copy();
hdr = copy.getHeader(getName());
if (hdr != null && hdr instanceof TcpHeader) copy.removeHeader(getName());
copy.setSrc(local_addr);
copy.setDest(local_addr);
evt = new Event(Event.MSG, copy);
/* Because Protocol.up() is never called by this bottommost layer, we call up() directly in the observer.
This allows e.g. PerfObserver to get the time of reception of a message */
if (observer != null) observer.up(evt, up_queue.size());
passUp(evt);
return;
}
if (Trace.trace)
Trace.info(
"TCP.sendUnicastMessage()",
"dest=" + msg.getDest() + ", hdrs:\n" + msg.printObjectHeaders());
try {
if (skip_suspected_members) {
if (suspected_mbrs.contains(dest)) {
if (Trace.trace)
Trace.info(
"TCP.sendUnicastMessage()",
"will not send unicast message to " + dest + " as it is currently suspected");
return;
}
}
ct.send(msg);
} catch (SocketException e) {
if (members.contains(dest)) {
if (!suspected_mbrs.contains(dest)) {
suspected_mbrs.add(dest);
passUp(new Event(Event.SUSPECT, dest));
}
}
}
}
void handleDiagnosticProbe(InetAddress sender, int port) {
try {
byte[] diag_rsp = getDiagResponse().getBytes();
DatagramPacket rsp = new DatagramPacket(diag_rsp, 0, diag_rsp.length, sender, port);
if (Trace.trace) {
Trace.info(
"UDP.handleDiagnosticProbe()", "sending diag response to " + sender + ":" + port);
}
sock.send(rsp);
} catch (Throwable t) {
Trace.error(
"UDP.handleDiagnosticProbe()",
"failed sending diag rsp to " + sender + ":" + port + ", exception=" + t);
}
}
void bundleAndSend() {
Map.Entry entry;
IpAddress dest;
ObjectOutputStream out;
InetAddress addr;
int port;
byte[] data;
List l;
if (Trace.trace) {
Trace.info(
"UDP.BundlingOutgoingPacketHandler.bundleAndSend()",
"\nsending msgs:\n" + dumpMessages(msgs));
}
synchronized (msgs) {
stopTimer();
if (msgs.size() == 0) {
return;
}
for (Iterator it = msgs.entrySet().iterator(); it.hasNext(); ) {
entry = (Map.Entry) it.next();
dest = (IpAddress) entry.getKey();
addr = dest.getIpAddress();
port = dest.getPort();
l = (List) entry.getValue();
try {
out_stream.reset();
// BufferedOutputStream bos=new BufferedOutputStream(out_stream);
out_stream.write(Version.version_id, 0, Version.version_id.length); // write the version
// bos.write(Version.version_id, 0, Version.version_id.length); // write the version
out = new ObjectOutputStream(out_stream);
// out=new ObjectOutputStream(bos);
l.writeExternal(out);
out.close(); // needed if out buffers its output to out_stream
data = out_stream.toByteArray();
doSend(data, addr, port);
} catch (IOException e) {
Trace.error(
"UDP.BundlingOutgoingPacketHandle.bundleAndSend()",
"exception sending msg (to dest=" + dest + "): " + e);
}
}
msgs.clear();
}
}
public void run() {
Message msg;
while (outgoing_queue != null && outgoing_packet_handler != null) {
try {
msg = (Message) outgoing_queue.remove();
handleMessage(msg);
} catch (QueueClosedException closed_ex) {
if (Trace.trace) {
Trace.info("UDP.OutgoingPacketHandler.run()", "packet_handler thread terminating");
}
break;
} catch (Throwable t) {
Trace.error(
"UDP.OutgoingPacketHandler.run()",
"exception sending packet: " + Util.printStackTrace(t));
}
msg = null; // let's give the poor garbage collector a hand...
}
}
/**
* Caller by the layer above this layer. Usually we just put this Message into the send queue and
* let one or more worker threads handle it. A worker thread then removes the Message from the
* send queue, performs a conversion and adds the modified Message to the send queue of the layer
* below it, by calling Down).
*/
public void down(Event evt) {
Message msg;
Object dest_addr;
if (evt.getType() != Event.MSG) { // unless it is a message handle it and respond
handleDownEvent(evt);
return;
}
// ****************** profiling ******************
/*if(num_msgs == 0) {
start=System.currentTimeMillis();
num_msgs++;
}
else if(num_msgs >= 1000) {
stop=System.currentTimeMillis();
long total_time=stop-start;
double msgs_per_msec=num_msgs / (double)total_time;
if(Trace.trace)
Trace.info("UDP.down.profile()",
"total_time=" + total_time + ", msgs/ms=" + msgs_per_msec);
num_msgs=0;
}
else {
num_msgs++;
}*/
// ****************** profiling ******************
msg = (Message) evt.getArg();
if (udp_hdr != null && udp_hdr.group_addr != null) {
// added patch by Roland Kurmann (March 20 2003)
msg.putHeader(name, udp_hdr);
}
dest_addr = msg.getDest();
// Because we don't call Protocol.passDown(), we notify the observer directly (e.g.
// PerfObserver).
// This way, we still have performance numbers for UDP
if (observer != null) {
observer.passDown(evt);
}
if (dest_addr == null) { // 'null' means send to all group members
if (ip_mcast) {
if (mcast_addr == null) {
Trace.error(
"UDP.down()",
"dest address of message is null, and "
+ "sending to default address fails as mcast_addr is null, too !"
+ " Discarding message "
+ Util.printEvent(evt));
return;
}
// if we want to use IP multicast, then set the destination of the message
msg.setDest(mcast_addr);
} else {
// sends a separate UDP message to each address
sendMultipleUdpMessages(msg, members);
return;
}
}
try {
sendUdpMessage(msg);
} catch (Exception e) {
Trace.error("UDP.down()", "exception=" + e + ", msg=" + msg + ", mcast_addr=" + mcast_addr);
}
}
/**
* 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;
}
public void run() {
DatagramPacket packet;
byte receive_buf[] = new byte[65535];
int len;
byte[] tmp, data;
// moved out of loop to avoid excessive object creations (bela March 8 2001)
packet = new DatagramPacket(receive_buf, receive_buf.length);
while (mcast_receiver != null && mcast_sock != null) {
try {
packet.setData(receive_buf, 0, receive_buf.length);
mcast_sock.receive(packet);
len = packet.getLength();
data = packet.getData();
if (len == 1 && data[0] == 0) {
if (Trace.debug) {
Trace.info("UDP.run()", "received dummy packet");
}
continue;
}
if (len == 4) { // received a diagnostics probe
if (data[0] == 'd' && data[1] == 'i' && data[2] == 'a' && data[3] == 'g') {
handleDiagnosticProbe(packet.getAddress(), packet.getPort());
continue;
}
}
if (Trace.debug) {
Trace.info(
"UDP.receive()",
"received (mcast) "
+ packet.getLength()
+ " bytes from "
+ packet.getAddress()
+ ":"
+ packet.getPort()
+ " (size="
+ len
+ " bytes)");
}
if (len > receive_buf.length) {
Trace.error(
"UDP.run()",
"size of the received packet ("
+ len
+ ") is bigger than "
+ "allocated buffer ("
+ receive_buf.length
+ "): will not be able to handle packet. "
+ "Use the FRAG protocol and make its frag_size lower than "
+ receive_buf.length);
}
if (Version.compareTo(data) == false) {
Trace.warn(
"UDP.run()",
"packet from "
+ packet.getAddress()
+ ":"
+ packet.getPort()
+ " has different version ("
+ Version.printVersionId(data, Version.version_id.length)
+ ") from ours ("
+ Version.printVersionId(Version.version_id)
+ "). This may cause problems");
}
if (use_incoming_packet_handler) {
tmp = new byte[len];
System.arraycopy(data, 0, tmp, 0, len);
incoming_queue.add(tmp);
} else {
handleIncomingUdpPacket(data);
}
} catch (SocketException sock_ex) {
if (Trace.trace) {
Trace.info("UDP.run()", "multicast socket is closed, exception=" + sock_ex);
}
break;
} catch (InterruptedIOException io_ex) { // thread was interrupted
; // go back to top of loop, where we will terminate loop
} catch (Throwable ex) {
Trace.error("UDP.run()", "exception=" + ex + ", stack trace=" + Util.printStackTrace(ex));
Util.sleep(300); // so we don't get into 100% cpu spinning (should NEVER happen !)
}
}
if (Trace.trace) {
Trace.info("UDP.run()", "multicast thread terminated");
}
}
/**
* Assigns the new ltime. Installs view and view_id. Changes role to coordinator if necessary.
* Sends VIEW_CHANGE event up and down the stack.
*/
public void installView(ViewId new_view, Vector mbrs) {
Object coord;
int rc;
synchronized (view_mutex) { // serialize access to views
ltime = Math.max(new_view.getId(), ltime); // compute Lamport logical time
if (Trace.trace) Trace.info("GMS.installView()", "received view change, vid=" + new_view);
/* Check for self-inclusion: if I'm not part of the new membership, I just discard it.
This ensures that messages sent in view V1 are only received by members of V1 */
if (checkSelfInclusion(mbrs) == false) {
if (Trace.trace)
Trace.warn("GMS.installView()", "I'm not member of " + mbrs + ", discarding");
return;
}
if (view_id == null) {
if (new_view == null) {
Trace.error("GMS.installView()", "view_id and new_view are null !");
return;
} else { // view_id is null, new_view not: just install new_view (we're still a client)
view_id = (ViewId) new_view.clone();
}
} else {
if (new_view == null) { // this should never happen though !
Trace.error("GMS.installView()", "new_view is null !");
return;
} else { // both view_id and new_view are not null
rc = new_view.compareTo(view_id); // rc should always be a positive number
if (rc <= 0) { // don't accept view id lower than our own
if (Trace.trace) {
Trace.warn(
"GMS.installView()",
"received view <= current view; discarding it ! "
+ "(view_id: "
+ view_id
+ ", new_view: "
+ new_view
+ ")");
}
return;
} else { // the check for vid equality was okay, assign new_view to view_id
if (new_view.getCoordAddress() != null) {
view_id = new ViewId(new_view.getCoordAddress(), new_view.getId());
} else {
view_id = new ViewId(view_id.getCoordAddress(), new_view.getId());
}
}
}
}
if (mbrs != null && mbrs.size() > 0) members.set(mbrs);
// Send VIEW_CHANGE event up and down the stack:
Event view_event = new Event(Event.VIEW_CHANGE, makeView(members.getMembers()));
passDown(view_event); // needed e.g. by failure detector or UDP
passUp(view_event);
coord = determineCoordinator();
if (coord != null
&& coord.equals(local_addr)
&& !(coord.equals(new_view.getCoordAddress()))) {
becomeCoordinator();
}
}
}
