/**
* An event is to be sent down the stack. The layer may want to examine its type and perform some
* action on it, depending on the event's type. If the event is a message MSG, then the layer may
* need to add a header to it (or do nothing at all) before sending it down the stack using <code>
* PassDown</code>. In case of a GET_ADDRESS event (which tries to retrieve the stack's address
* from one of the bottom layers), the layer may need to send a new response event back up the
* stack using <code>up_prot.up()</code>. The PING protocol is interested in several different
* down events, Event.FIND_INITIAL_MBRS - sent by the GMS layer and expecting a GET_MBRS_OK
* Event.TMP_VIEW and Event.VIEW_CHANGE - a view change event Event.BECOME_SERVER - called after
* client has joined and is fully working group member Event.CONNECT, Event.DISCONNECT.
*/
@SuppressWarnings("unchecked")
public Object down(Event evt) {
switch (evt.getType()) {
case Event.FIND_INITIAL_MBRS: // sent by GMS layer
case Event.FIND_ALL_VIEWS:
// sends the GET_MBRS_REQ to all members, waits 'timeout' ms or until 'num_initial_members'
// have been retrieved
long start = System.currentTimeMillis();
boolean find_all_views = evt.getType() == Event.FIND_ALL_VIEWS;
Promise<JoinRsp> promise = (Promise<JoinRsp>) evt.getArg();
List<PingData> rsps = find_all_views ? findAllViews(promise) : findInitialMembers(promise);
long diff = System.currentTimeMillis() - start;
if (log.isTraceEnabled())
log.trace("discovery took " + diff + " ms: responses: " + Util.printPingData(rsps));
return rsps;
case Event.TMP_VIEW:
case Event.VIEW_CHANGE:
List<Address> tmp;
view = (View) evt.getArg();
if ((tmp = view.getMembers()) != null) {
synchronized (members) {
members.clear();
members.addAll(tmp);
}
}
current_coord = !members.isEmpty() ? members.get(0) : null;
is_coord = current_coord != null && local_addr != null && current_coord.equals(local_addr);
return down_prot.down(evt);
case Event.BECOME_SERVER: // called after client has joined and is fully working group member
down_prot.down(evt);
is_server = true;
return null;
case Event.SET_LOCAL_ADDRESS:
local_addr = (Address) evt.getArg();
return down_prot.down(evt);
case Event.CONNECT:
case Event.CONNECT_WITH_STATE_TRANSFER:
case Event.CONNECT_USE_FLUSH:
case Event.CONNECT_WITH_STATE_TRANSFER_USE_FLUSH:
is_leaving = false;
group_addr = (String) evt.getArg();
Object ret = down_prot.down(evt);
handleConnect();
return ret;
case Event.DISCONNECT:
is_leaving = true;
handleDisconnect();
return down_prot.down(evt);
default:
return down_prot.down(evt); // Pass on to the layer below us
}
}
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);
}
}
}
public Object up(Event evt) {
if (evt.getType() == Event.SET_LOCAL_ADDRESS) {
localAddress = evt.getArg();
if (discard_dialog != null) discard_dialog.setTitle("Discard dialog (" + localAddress + ")");
}
return up_prot.up(evt);
}
public Object up(Event evt) {
switch (evt.getType()) {
case Event.MSG:
Message msg = (Message) evt.getArg();
DaisyHeader hdr = (DaisyHeader) msg.getHeader(getId());
if (hdr == null) break;
// 1. forward the message to the next in line if ttl > 0
short ttl = hdr.getTTL();
if (log.isTraceEnabled())
log.trace(local_addr + ": received message from " + msg.getSrc() + " with ttl=" + ttl);
if (--ttl > 0) {
Message copy = msg.copy(true);
copy.setDest(next);
copy.putHeader(getId(), new DaisyHeader(ttl));
msgs_forwarded++;
if (log.isTraceEnabled())
log.trace(local_addr + ": forwarding message to " + next + " with ttl=" + ttl);
down_prot.down(new Event(Event.MSG, copy));
}
// 2. Pass up
msg.setDest(null);
break;
}
return up_prot.up(evt);
}
/**
* Fragment a packet if larger than frag_size (add a header). Otherwise just pass down. Only add a
* header if fragmentation is needed !
*/
public Object down(Event evt) {
switch (evt.getType()) {
case Event.MSG:
Message msg = (Message) evt.getArg();
long size = msg.getLength();
num_sent_msgs.incrementAndGet();
if (size > frag_size) {
if (log.isTraceEnabled()) {
log.trace(
new StringBuilder("message's buffer size is ")
.append(size)
.append(", will fragment ")
.append("(frag_size=")
.append(frag_size)
.append(')'));
}
fragment(msg); // Fragment and pass down
return null;
}
break;
case Event.VIEW_CHANGE:
handleViewChange((View) evt.getArg());
break;
case Event.CONFIG:
Object ret = down_prot.down(evt);
if (log.isDebugEnabled()) log.debug("received CONFIG event: " + evt.getArg());
handleConfigEvent((Map<String, Object>) evt.getArg());
return ret;
}
return down_prot.down(evt); // Pass on to the layer below us
}
public Object down(Event evt) {
if (drop_next && evt.getType() == Event.MSG) {
drop_next = false;
return null;
}
return super.down(evt);
}
public Object down(Event evt) {
if (evt.getType() == Event.MSG) {
Message msg = (Message) evt.getArg();
if (msg.getLength() > 0) {
try {
Long payload = msg.getObject();
if (payload != null) {
if (payload == seqno) {
synchronized (this) {
if (num_discards < 3) {
num_discards++;
return null;
}
}
}
if (payload == duplicate) { // inject a duplicate message
super.down(
evt); // pass it down, will passed down a second time by the default
// down_prot.down(evt)
}
}
} catch (Throwable t) {;
}
}
}
return down_prot.down(evt);
}
/**
* <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);
}
// Priority handling, otherwise GMS.down(DISCONNECT) would block !
// Similar to FLUSH protocol
public void receiveDownEvent(Event evt) {
if (evt.getType() == Event.BLOCK_OK) {
passDown(evt);
return;
}
super.receiveDownEvent(evt);
}
public Object up(Event evt) {
switch (evt.getType()) {
case Event.MSG:
Message msg = (Message) evt.getArg();
ForkHeader hdr = (ForkHeader) msg.getHeader(id);
if (hdr == null) break;
if (hdr.fork_stack_id == null)
throw new IllegalArgumentException("header has a null fork_stack_id");
Protocol bottom_prot = get(hdr.fork_stack_id);
return bottom_prot != null
? bottom_prot.up(evt)
: this.unknownForkHandler.handleUnknownForkStack(msg, hdr.fork_stack_id);
case Event.VIEW_CHANGE:
for (Protocol bottom : fork_stacks.values()) bottom.up(evt);
break;
case Event.STATE_TRANSFER_OUTPUTSTREAM:
if (!process_state_events) break;
getStateFromMainAndForkChannels(evt);
return null;
case Event.STATE_TRANSFER_INPUTSTREAM:
if (!process_state_events) break;
setStateInMainAndForkChannels((InputStream) evt.getArg());
return null;
}
return up_prot.up(evt);
}
/**
* If event is a message, if it is fragmented, re-assemble fragments into big message and pass up
* the stack.
*/
public Object up(Event evt) {
switch (evt.getType()) {
case Event.MSG:
Message msg = (Message) evt.getArg();
FragHeader hdr = (FragHeader) msg.getHeader(this.id);
if (hdr != null) { // needs to be defragmented
unfragment(msg, hdr); // Unfragment and possibly pass up
return null;
} else {
num_received_msgs.incrementAndGet();
}
break;
case Event.VIEW_CHANGE:
handleViewChange((View) evt.getArg());
break;
case Event.CONFIG:
Object ret = up_prot.up(evt);
if (log.isDebugEnabled()) log.debug("received CONFIG event: " + evt.getArg());
handleConfigEvent((Map<String, Object>) evt.getArg());
return ret;
}
return up_prot.up(evt); // Pass up to the layer above us by default
}
public Object up(Event evt) {
switch (evt.getType()) {
case Event.MSG:
Message msg = (Message) evt.getArg();
LockingHeader hdr = (LockingHeader) msg.getHeader(id);
if (hdr == null) break;
Request req = (Request) msg.getObject();
if (log.isTraceEnabled())
log.trace("[" + local_addr + "] <-- [" + msg.getSrc() + "] " + req);
switch (req.type) {
case GRANT_LOCK:
case RELEASE_LOCK:
handleLockRequest(req);
break;
case LOCK_GRANTED:
handleLockGrantedResponse(req.lock_name, req.owner, msg.getSrc());
break;
case LOCK_DENIED:
handleLockDeniedResponse(req.lock_name, req.owner);
break;
case CREATE_LOCK:
handleCreateLockRequest(req.lock_name, req.owner);
break;
case DELETE_LOCK:
handleDeleteLockRequest(req.lock_name);
break;
case COND_SIG:
case COND_SIG_ALL:
handleSignalRequest(req);
break;
case LOCK_AWAIT:
handleAwaitRequest(req.lock_name, req.owner);
handleLockRequest(req);
break;
case DELETE_LOCK_AWAIT:
handleDeleteAwaitRequest(req.lock_name, req.owner);
break;
case SIG_RET:
handleSignalResponse(req.lock_name, req.owner);
break;
case CREATE_AWAITER:
handleCreateAwaitingRequest(req.lock_name, req.owner);
break;
case DELETE_AWAITER:
handleDeleteAwaitingRequest(req.lock_name, req.owner);
break;
default:
log.error("Request of type " + req.type + " not known");
break;
}
return null;
case Event.VIEW_CHANGE:
handleView((View) evt.getArg());
break;
}
return up_prot.up(evt);
}
public Object down(Event evt) {
if (channel != null) {
if (evt.getType() == Event.MSG && !(channel.isConnected() || channel.isConnecting()))
throw new IllegalStateException("channel is not connected");
return channel.down(evt);
}
return null;
}
public Object up(Event evt) {
switch (evt.getType()) {
case Event.VIEW_CHANGE:
handleView(evt.getArg());
break;
}
return up_prot.up(evt);
}
public Object down(Event evt) {
switch (evt.getType()) {
case Event.SET_LOCAL_ADDRESS:
local_addr = (Address) evt.getArg();
break;
}
return down_prot.down(evt);
}
@SuppressWarnings("unchecked")
public Object up(Event evt) {
if (evt.getType() == Event.CONFIG) {
if (bind_addr == null) {
Map<String, Object> config = (Map<String, Object>) evt.getArg();
bind_addr = (InetAddress) config.get("bind_addr");
}
return up_prot.up(evt);
}
return super.up(evt);
}
public Object up(Event evt) {
switch (evt.getType()) {
case Event.MSG:
Message msg = (Message) evt.getArg();
// Do something with the event, e.g. extract the message and remove a header.
// Optionally pass up
break;
}
return up_prot.up(evt); // Pass up to the layer above us
}
public Object down(Event evt) {
switch (evt.getType()) {
case Event.TMP_VIEW:
case Event.VIEW_CHANGE:
handleViewChange((View) evt.getArg());
break;
case Event.GET_STATE:
Address target;
StateTransferInfo info = (StateTransferInfo) evt.getArg();
if (info.target == null) {
target = determineCoordinator();
} else {
target = info.target;
if (target.equals(local_addr)) {
log.error("%s: cannot fetch state from myself", local_addr);
target = null;
}
}
if (target == null) {
log.debug("%s: first member (no state)", local_addr);
up_prot.up(new Event(Event.GET_STATE_OK, new StateTransferInfo()));
} else {
Message state_req =
new Message(target)
.putHeader(this.id, new StateHeader(StateHeader.STATE_REQ))
.setFlag(Message.Flag.DONT_BUNDLE, Message.Flag.OOB, Message.Flag.SKIP_BARRIER);
log.debug("%s: asking %s for state", local_addr, target);
// suspend sending and handling of message garbage collection gossip messages,
// fixes bugs #943480 and #938584). Wake up when state has been received
/*if(log.isDebugEnabled())
log.debug("passing down a SUSPEND_STABLE event");
down_prot.down(new Event(Event.SUSPEND_STABLE, new Long(info.timeout)));*/
waiting_for_state_response = true;
start = System.currentTimeMillis();
down_prot.down(new Event(Event.MSG, state_req));
}
return null; // don't pass down any further !
case Event.CONFIG:
Map<String, Object> config = (Map<String, Object>) evt.getArg();
if (config != null && config.containsKey("flush_supported")) {
flushProtocolInStack = true;
}
break;
case Event.SET_LOCAL_ADDRESS:
local_addr = (Address) evt.getArg();
break;
}
return down_prot.down(evt); // pass on to the layer below us
}
/**
* An event is to be sent down the stack. The layer may want to examine its type and perform some
* action on it, depending on the event's type. If the event is a message MSG, then the layer may
* need to add a header to it (or do nothing at all) before sending it down the stack using <code>
* down_prot.down()</code>. In case of a GET_ADDRESS event (which tries to retrieve the stack's
* address from one of the bottom layers), the layer may need to send a new response event back up
* the stack using <code>up_prot.up()</code>.
*/
public Object down(Event evt) {
GMS.GmsHeader hdr = getGMSHeader(evt);
if (hdr != null && needsAuthentication(hdr)) {
// we found a join request message - now add an AUTH Header
Message msg = (Message) evt.getArg();
AuthHeader authHeader = new AuthHeader(this.auth_token);
msg.putHeader(this.id, authHeader);
}
if (evt.getType() == Event.SET_LOCAL_ADDRESS) local_addr = (Address) evt.getArg();
return down_prot.down(evt);
}
public Object up(Event evt) {
switch (evt.getType()) {
case Event.MSG:
Message msg = (Message) evt.getArg();
NakAckHeader2 hdr = (NakAckHeader2) msg.getHeader(ID);
if (hdr != null && hdr.getType() == NakAckHeader2.MSG) {
long seqno = hdr.getSeqno();
msgs.add(seqno);
System.out.println("-- received message #" + seqno + " from " + msg.getSrc());
}
break;
}
return null;
}
/**
* handle the UP event.
*
* @param evt - the event being send from the stack
*/
public void up(Event evt) {
passUp(evt);
switch (evt.getType()) {
case Event.CONFIG:
passUp(evt);
if (Trace.trace) {
Trace.info("UDP.up()", "received CONFIG event: " + evt.getArg());
}
handleConfigEvent((HashMap) evt.getArg());
return;
}
passUp(evt);
}
public Object down(Event evt) {
switch (evt.getType()) {
case Event.MSG:
Message msg = (Message) evt.getArg();
NakAckHeader2 hdr = (NakAckHeader2) msg.getHeader(ID);
if (hdr == null) break;
if (hdr.getType() == NakAckHeader2.XMIT_REQ) {
SeqnoList seqnos = (SeqnoList) msg.getObject();
System.out.println("-- XMIT-REQ: request retransmission for " + seqnos);
for (Long seqno : seqnos) xmit_requests.add(seqno);
}
break;
}
return null;
}
public Object down(Event evt) {
Object retval = super.down(evt);
switch (evt.getType()) {
case Event.VIEW_CHANGE:
for (Address logical_addr : members) {
PhysicalAddress physical_addr =
(PhysicalAddress) down_prot.down(new Event(Event.GET_PHYSICAL_ADDRESS, logical_addr));
if (physical_addr != null && !initial_hosts.contains(physical_addr)) {
dynamic_hosts.addIfAbsent(physical_addr);
}
}
break;
}
return retval;
}
/**
* <b>Callback</b>. Called by superclass when event may be handled.
*
* <p><b>Do not use <code>PassUp</code> in this method as the event is passed up by default by the
* superclass after this method returns !</b>
*
* @return boolean Defaults to true. If false, event will not be passed up the stack.
*/
public boolean handleUpEvent(Event evt) {
switch (evt.getType()) {
case Event.CONNECT_OK: // sent by someone else, but WE are responsible for sending this !
case Event.DISCONNECT_OK: // dito (e.g. sent by UDP layer)
return false;
case Event.SET_LOCAL_ADDRESS:
local_addr = (Address) evt.getArg();
if (print_local_addr) {
System.out.println(
"\n-------------------------------------------------------\n"
+ "2.1GMS: address is "
+ local_addr
+ "\n-------------------------------------------------------");
}
return true; // pass up
case Event.SUSPECT:
try {
event_queue.add(evt);
} catch (Exception e) {
}
return true; // pass up
case Event.MERGE:
try {
event_queue.add(evt);
} catch (Exception e) {
}
return false; // don't pass up
case Event.FLUSH_OK:
synchronized (flush_mutex) {
flush_rsp = (FlushRsp) evt.getArg();
flush_mutex.notify();
}
return false; // don't pass up
case Event.REBROADCAST_MSGS_OK:
synchronized (rebroadcast_mutex) {
rebroadcast_mutex.notify();
}
return false; // don't pass up
}
return impl.handleUpEvent(evt);
}
public Object down(final Event evt) {
switch (evt.getType()) {
case Event.MSG:
final Message msg = (Message) evt.getArg();
if (msg.getDest() != null) break; // only process multicast messages
if (next == null) // view hasn't been received yet, use the normal transport
break;
// we need to copy the message, as we cannot do a msg.setSrc(next): the next retransmission
// would use 'next' as destination !
Message copy = msg.copy(true);
short hdr_ttl = (short) (loopback ? view_size - 1 : view_size);
DaisyHeader hdr = new DaisyHeader(hdr_ttl);
copy.setDest(next);
copy.putHeader(getId(), hdr);
msgs_sent++;
if (loopback) {
if (log.isTraceEnabled())
log.trace(new StringBuilder("looping back message ").append(msg));
if (msg.getSrc() == null) msg.setSrc(local_addr);
Executor pool = msg.isFlagSet(Message.Flag.OOB) ? oob_pool : default_pool;
pool.execute(() -> up_prot.up(evt));
}
return down_prot.down(new Event(Event.MSG, copy));
case Event.VIEW_CHANGE:
handleView((View) evt.getArg());
break;
case Event.TMP_VIEW:
view_size = ((View) evt.getArg()).size();
break;
case Event.SET_LOCAL_ADDRESS:
local_addr = (Address) evt.getArg();
break;
}
return down_prot.down(evt);
}
public Object down(Event evt) {
switch (evt.getType()) {
case Event.MSG:
Message msg = (Message) evt.getArg();
if (msg.getLength() == 0 && !encrypt_entire_message) break;
try {
if (queue_down) {
log.trace("queueing down message as no session key established: %s", msg);
downMessageQueue.put(msg); // queue messages if we are waiting for a new key
} else {
// make sure the down queue is drained first to keep ordering
if (!suppliedKey) drainDownQueue();
encryptAndSend(msg);
}
} catch (Exception e) {
log.warn("unable to send message down", e);
}
return null;
case Event.VIEW_CHANGE:
View view = (View) evt.getArg();
log.debug("new view: " + view);
if (!suppliedKey) handleViewChange(view, false);
break;
case Event.SET_LOCAL_ADDRESS:
local_addr = (Address) evt.getArg();
log.debug("set local address to %s", local_addr);
break;
case Event.TMP_VIEW:
view = (View) evt.getArg();
if (!suppliedKey) {
// if a tmp_view then we are trying to become coordinator so
// make us keyserver
handleViewChange(view, true);
}
break;
}
return down_prot.down(evt);
}
/**
* An event was received from the layer below. Usually the current layer will want to examine the
* event type and - depending on its type - perform some computation (e.g. removing headers from a
* MSG event type, or updating the internal membership list when receiving a VIEW_CHANGE event).
* Finally the event is either a) discarded, or b) an event is sent down the stack using <code>
* down_prot.down()</code> or c) the event (or another event) is sent up the stack using <code>
* up_prot.up()</code>.
*/
public Object up(Event evt) {
switch (evt.getType()) {
case Event.MSG:
Message msg = (Message) evt.getArg();
// If we have a join or merge request --> authenticate, else pass up
GMS.GmsHeader gms_hdr = getGMSHeader(evt);
if (gms_hdr != null && needsAuthentication(gms_hdr)) {
AuthHeader auth_hdr = (AuthHeader) msg.getHeader(id);
if (auth_hdr == null)
throw new IllegalStateException("found GMS join or merge request but no AUTH header");
if (!handleAuthHeader(gms_hdr, auth_hdr, msg)) // authentication failed
return null; // don't pass up
}
break;
}
if (!callUpHandlers(evt)) return null;
return up_prot.up(evt);
}
public Object up(Event evt) {
Message msg;
Address dst, src;
Unicast2Header hdr;
switch (evt.getType()) {
case Event.MSG:
msg = (Message) evt.getArg();
dst = msg.getDest();
if (dst == null || msg.isFlagSet(Message.NO_RELIABILITY)) // only handle unicast messages
break; // pass up
// changed from removeHeader(): we cannot remove the header because if we do loopback=true
// at the
// transport level, we will not have the header on retransmit ! (bela Aug 22 2006)
hdr = (Unicast2Header) msg.getHeader(this.id);
if (hdr == null) break;
src = msg.getSrc();
switch (hdr.type) {
case Unicast2Header.DATA: // received regular message
handleDataReceived(src, hdr.seqno, hdr.conn_id, hdr.first, msg, evt);
return null; // we pass the deliverable message up in handleDataReceived()
case Unicast2Header.XMIT_REQ: // received ACK for previously sent message
handleXmitRequest(src, hdr.seqno, hdr.high_seqno);
break;
case Unicast2Header.SEND_FIRST_SEQNO:
handleResendingOfFirstMessage(src, hdr.seqno);
break;
case Unicast2Header.STABLE:
stable(msg.getSrc(), hdr.conn_id, hdr.seqno, hdr.high_seqno);
break;
default:
log.error("UnicastHeader type " + hdr.type + " not known !");
break;
}
return null;
}
return up_prot.up(evt); // Pass up to the layer above us
}
public Object down(Event evt) {
switch (evt.getType()) {
case Event.TMP_VIEW:
case Event.VIEW_CHANGE:
List<Address> new_members = ((View) evt.getArg()).getMembers();
synchronized (members) {
members.clear();
if (new_members != null && !new_members.isEmpty()) members.addAll(new_members);
}
return down_prot.down(evt);
case Event.MSG:
Message msg = (Message) evt.getArg();
// Do something with the event, e.g. add a header to the message
// Optionally pass down
break;
}
return down_prot.down(evt); // Pass on to the layer below us
}
/**
* If event is a message, if it is fragmented, re-assemble fragments into big message and pass up
* the stack.
*/
public Object up(Event evt) {
switch (evt.getType()) {
case Event.MSG:
Message msg = (Message) evt.getArg();
FragHeader hdr = (FragHeader) msg.getHeader(this.id);
if (hdr != null) { // needs to be defragmented
Message assembled_msg = unfragment(msg, hdr);
if (assembled_msg != null) up_prot.up(new Event(Event.MSG, assembled_msg));
return null;
} else {
num_received_msgs++;
}
break;
case Event.VIEW_CHANGE:
handleViewChange((View) evt.getArg());
break;
}
return up_prot.up(evt); // Pass up to the layer above us by default
}