/**
* a DatagramChannel has data ready - process all the pending packets, whether its for a
* rdpserversocket or rdpconnection.
*/
void processActiveChannel(DatagramChannel dc) throws ClosedChannelException {
RDPPacket packet;
int count = 0;
// read in the packet
try {
Set<RDPConnection> needsAckConnections = new HashSet<RDPConnection>();
while ((packet = RDPServer.receivePacket(dc)) != null) {
if (Log.loggingNet)
Log.net(
"RDPServer.processActiveChannel: Starting iteration with count of "
+ count
+ " packets");
// see if there is a connection already for this packet
InetAddress remoteAddr = packet.getInetAddress();
int remotePort = packet.getPort();
int localPort = dc.socket().getLocalPort();
ConnectionInfo conInfo = new ConnectionInfo(remoteAddr, remotePort, localPort);
RDPConnection con = RDPServer.getConnection(dc, conInfo);
if (con != null) {
if (Log.loggingNet)
Log.net("RDPServer.processActiveChannel: found an existing connection: " + con);
count++;
if (processExistingConnection(con, packet)) needsAckConnections.add(con);
// Prevent this from blocking getActiveChannels by
// putting an upper bound on the number of packets
// processed
if (count >= 20) break;
continue;
} else {
Log.net("RDPServer.processActiveChannel: did not find an existing connection");
}
// there is no connection,
// see if there is a socket listening for new connection
RDPServerSocket rdpSocket = RDPServer.getRDPSocket(dc);
if (rdpSocket != null) {
count++;
processNewConnection(rdpSocket, packet);
return;
}
return;
}
// Finally, send out the acks
for (RDPConnection con : needsAckConnections) {
RDPPacket replyPacket = new RDPPacket(con);
con.sendPacketImmediate(replyPacket, false);
}
} catch (ClosedChannelException ex) {
Log.error("RDPServer.processActiveChannel: ClosedChannel " + dc.socket());
throw ex;
} finally {
if (Log.loggingNet)
Log.net("RDPServer.processActiveChannel: Returning after processing " + count + " packets");
}
}
/**
* removes this connection from the connections map the datagram channel still sticks around in
* case it needs to be reused
*/
static void removeConnection(RDPConnection con) {
lock.lock();
try {
if (Log.loggingNet) Log.net("RDPServer.removeConnection: removing con " + con);
con.setState(RDPConnection.CLOSED);
DatagramChannel dc = con.getDatagramChannel();
// first we get the set of connections attached to the given dc
Map<ConnectionInfo, RDPConnection> dcConMap = allConMap.get(dc);
if (dcConMap == null) {
throw new MVRuntimeException("RDPServer.removeConnection: cannot find dc");
}
int localPort = con.getLocalPort();
int remotePort = con.getRemotePort();
InetAddress remoteAddr = con.getRemoteAddr();
ConnectionInfo conInfo = new ConnectionInfo(remoteAddr, remotePort, localPort);
Object rv = dcConMap.remove(conInfo);
if (rv == null) {
throw new MVRuntimeException("RDPServer.removeConnection: could not find the connection");
}
// close the datagramchannel if needed
// conditions: no other connections on this datagramchannel
// no socket listening on this datagramchannel
if (dcConMap.isEmpty()) {
Log.net("RDPServer.removeConnection: no other connections for this datagramchannel (port)");
// there are no more connections on this datagram channel
// check if there is a serversocket listening
if (getRDPSocket(dc) == null) {
Log.net("RDPServer.removeConnection: no socket listening on this port - closing");
// no socket either, close the datagramchannel
dc.socket().close();
channelMap.remove(localPort);
Log.net("RDPServer.removeConnection: closed and removed datagramchannel/socket");
} else {
Log.net("RDPServer.removeConnection: there is a socket listening on this port");
}
} else {
Log.net("RDPServer.removeConnection: there are other connections on this port");
}
} finally {
lock.unlock();
}
}
/** rdpserversocket wants to bind on a local port */
static DatagramChannel bind(Integer port, int receiveBufferSize)
throws java.net.BindException, java.io.IOException, java.net.SocketException {
lock.lock();
try {
// see if there is an existing datagramchannel bound to this port
DatagramChannel dc = channelMap.get(port);
if (dc != null) {
throw new java.net.BindException("RDPServer.bind: port is already used");
}
// make a new datagram channel
dc = DatagramChannel.open();
dc.configureBlocking(false);
dc.socket().setReceiveBufferSize(receiveBufferSize);
if (port == null) {
if (Log.loggingNet) Log.net("RDPServer.bind: binding to a random system port");
dc.socket().bind(null);
} else {
if (Log.loggingNet) Log.net("RDPServer.bind: binding to port " + port);
dc.socket().bind(new InetSocketAddress(port));
}
int resultingPort = dc.socket().getLocalPort();
if (Log.loggingNet) Log.net("RDPServer.bind: resulting port=" + resultingPort);
// add the channel to the channel map
channelMap.put(resultingPort, dc);
if (Log.loggingNet) Log.net("RDPServer.bind: added dc to channel map");
// add the channel to the newChannelsSet
// we want to register this channel with the selector
// but the selector thread needs to do that,
// so place it in this set, and wake up the selector
newChannelSet.add(dc);
if (Log.loggingNet) Log.net("RDPServer.bind: added dc to newChannelSet");
// in case the rdpserver was waiting while it had no sockets,
// signal it
channelMapNotEmpty.signal();
Log.net("RDPServer.bind: signalled channel map not empty condition");
// wakeup the selector -
// it needs to register the new channel with itself
selector.wakeup();
if (Log.loggingNet) Log.net("RDPServer.bind: woke up selector");
return dc;
} finally {
lock.unlock();
}
}
/** make sure the packet as the remote address and remote port set */
static void sendPacket(DatagramChannel dc, RDPPacket packet) {
sendMeter.add();
// allocate a buffer
int bufSize = 100 + (packet.numEacks() * 4);
if (packet.getData() != null) {
bufSize += packet.getData().length;
sendDataMeter.add();
}
MVByteBuffer buf = new MVByteBuffer(bufSize);
packet.toByteBuffer(buf); // function flips the buffer
int remotePort = packet.getPort();
InetAddress remoteAddr = packet.getInetAddress();
if ((remotePort < 0) || (remoteAddr == null)) {
throw new MVRuntimeException("RDPServer.sendPacket: remotePort or addr is null");
}
try {
int bytes = dc.send(buf.getNioBuf(), new InetSocketAddress(remoteAddr, remotePort));
if (bytes == 0) {
Log.error("RDPServer.sendPacket: could not send packet, size=" + bufSize);
}
if (Log.loggingNet)
Log.net(
"RDPServer.sendPacket: remoteAddr="
+ remoteAddr
+ ", remotePort="
+ remotePort
+ ", numbytes sent="
+ bytes);
} catch (java.io.IOException e) {
Log.exception(
"RDPServer.sendPacket: remoteAddr="
+ remoteAddr
+ ", remotePort="
+ remotePort
+ ", got exception",
e);
throw new MVRuntimeException("RDPServer.sendPacket", e);
}
}
/** reads in an rdp packet from the datagram channel - blocking call */
static RDPPacket receivePacket(DatagramChannel dc) throws ClosedChannelException {
try {
if (dc == null) {
throw new MVRuntimeException("RDPServer.receivePacket: datagramChannel is null");
}
// get a packet from the reader
staticMVBuff.rewind();
InetSocketAddress addr = (InetSocketAddress) dc.receive(staticMVBuff.getNioBuf());
if (addr == null) {
return null;
}
RDPPacket packet = new RDPPacket();
packet.setPort(addr.getPort());
packet.setInetAddress(addr.getAddress());
packet.parse(staticMVBuff);
return packet;
} catch (ClosedChannelException ex) {
throw ex;
} catch (Exception e) {
throw new MVRuntimeException("error", e);
}
}
/** returns a list of rdpserversockets */
Set<DatagramChannel> getActiveChannels() throws InterruptedException, java.io.IOException {
lock.lock();
try {
while (channelMap.isEmpty()) {
channelMapNotEmpty.await();
}
} finally {
lock.unlock();
}
Set<SelectionKey> readyKeys = null;
do {
lock.lock();
try {
if (!newChannelSet.isEmpty()) {
if (Log.loggingNet) Log.net("RDPServer.getActiveChannels: newChannelSet is not null");
Iterator<DatagramChannel> iter = newChannelSet.iterator();
while (iter.hasNext()) {
DatagramChannel newDC = iter.next();
iter.remove();
newDC.register(selector, SelectionKey.OP_READ);
}
}
} finally {
lock.unlock();
}
int numReady = selector.select(); // this is a blocking call - thread safe
selectCalls++;
if (numReady == 0) {
if (Log.loggingNet) Log.net("RDPServer.getActiveChannels: selector returned 0");
continue;
}
readyKeys = selector.selectedKeys();
if (Log.loggingNet)
Log.net(
"RDPServer.getActiveChannels: called select - # of ready keys = "
+ readyKeys.size()
+ " == "
+ numReady);
} while (readyKeys == null || readyKeys.isEmpty());
lock.lock();
try {
// get a datagramchannel that is ready
Set<DatagramChannel> activeChannels = new HashSet<DatagramChannel>();
Iterator<SelectionKey> iter = readyKeys.iterator();
while (iter.hasNext()) {
SelectionKey key = iter.next();
if (Log.loggingNet)
Log.net(
"RDPServer.getActiveChannels: matched selectionkey: "
+ key
+ ", isAcceptable="
+ key.isAcceptable()
+ ", isReadable="
+ key.isReadable()
+ ", isValid="
+ key.isValid()
+ ", isWritable="
+ key.isWritable());
iter.remove(); // remove from the selected key list
if (!key.isReadable() || !key.isValid()) {
Log.error(
"RDPServer.getActiveChannels: Throwing exception: RDPServer: not readable or invalid");
throw new MVRuntimeException("RDPServer: not readable or invalid");
}
DatagramChannel dc = (DatagramChannel) key.channel();
activeChannels.add(dc);
}
if (Log.loggingNet)
Log.net(
"RDPServer.getActiveChannels: returning " + activeChannels.size() + " active channels");
return activeChannels;
} finally {
lock.unlock();
}
}