src/jlibrtp/RTCPReceiverThread.java
changeset 13 e684f11070d5
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jlibrtp/RTCPReceiverThread.java	Sat Mar 14 22:15:41 2009 +0100
@@ -0,0 +1,369 @@
+/**
+ * Java RTP Library (jlibrtp)
+ * Copyright (C) 2006 Arne Kepp
+ * 
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+package jlibrtp;
+
+import java.io.IOException;
+import java.net.DatagramPacket;
+import java.net.InetSocketAddress;
+import java.util.Enumeration;
+import java.util.Iterator;
+
+/**
+ * This thread hangs on the RTCP socket and waits for new packets
+ * 
+ * @author Arne Kepp
+ *
+ */
+public class RTCPReceiverThread extends Thread {
+	/** Parent RTP Session */
+	private RTPSession rtpSession = null;
+	/** Parent RTCP Session */
+	private RTCPSession rtcpSession = null;
+	
+	/**
+	 * Constructor for new thread
+	 * @param rtcpSession parent RTCP session
+	 * @param rtpSession parent RTP session
+	 */
+	RTCPReceiverThread(RTCPSession rtcpSession, RTPSession rtpSession) {
+		this.rtpSession = rtpSession;
+		this.rtcpSession = rtcpSession;
+		
+		if(RTPSession.rtpDebugLevel > 1) {
+			System.out.println("<-> RTCPReceiverThread created");
+		} 
+
+	}
+	
+	/**
+	 * Find out whether a participant with this SSRC is known.
+	 * 
+	 * If the user is unknown, and the system is operating in unicast mode,
+	 * try to match the ip-address of the sender to the ip address of a
+	 * previously unmatched target
+	 * 
+	 * @param ssrc the SSRC of the participant
+	 * @param packet the packet that notified us
+	 * @return the relevant participant, possibly newly created
+	 */
+	private Participant findParticipant(long ssrc, DatagramPacket packet) {
+		Participant p = rtpSession.partDb.getParticipant(ssrc);
+		if(p == null) {
+			Enumeration<Participant> enu = rtpSession.partDb.getParticipants();
+			while(enu.hasMoreElements()) {
+				Participant tmp = (Participant) enu.nextElement();
+				if(tmp.ssrc < 0 && 
+						(tmp.rtcpAddress.getAddress().equals(packet.getAddress())
+						|| tmp.rtpAddress.getAddress().equals(packet.getAddress()))) {
+					
+					// Best guess
+					System.out.println("RTCPReceiverThread: Got an unexpected packet from SSRC:" 
+							+ ssrc  + " @" + packet.getAddress().toString() + ", WAS able to match it." );
+					
+					tmp.ssrc = ssrc;
+					return tmp;
+				}
+			}
+			// Create an unknown sender
+			System.out.println("RTCPReceiverThread: Got an unexpected packet from SSRC:" 
+					+ ssrc  + " @" + packet.getAddress().toString() + ", was NOT able to match it." );
+			p = new Participant((InetSocketAddress) null, (InetSocketAddress) packet.getSocketAddress(), ssrc);
+			rtpSession.partDb.addParticipant(2,p);
+		}
+		return p;
+	}
+	
+	
+	/**
+	 * Parse a received UDP packet
+	 * 
+	 * Perform the header checks and extract the RTCP packets in it
+	 * 
+	 * @param packet the packet to be parsed
+	 * @return -1 if there was a problem, 0 if successfully parsed
+	 */
+	private int parsePacket(DatagramPacket packet) {
+
+		if(packet.getLength() % 4 != 0) {
+			if(RTPSession.rtcpDebugLevel > 2) {
+				System.out.println("RTCPReceiverThread.parsePacket got packet that had length " + packet.getLength());
+			}
+			return -1;
+		} else {
+			byte[] rawPkt = packet.getData();
+
+			// Parse the received compound RTCP (?) packet
+			CompRtcpPkt compPkt = new CompRtcpPkt(rawPkt, packet.getLength(), 
+					(InetSocketAddress) packet.getSocketAddress(), rtpSession);
+
+			if(this.rtpSession.debugAppIntf != null) {
+				String intfStr; 
+
+				if(rtpSession.mcSession) {
+					intfStr = this.rtcpSession.rtcpMCSock.getLocalSocketAddress().toString();
+				} else {
+					intfStr = this.rtpSession.rtpSock.getLocalSocketAddress().toString();
+				}
+
+				if( compPkt.problem == 0) {
+					String str = new String("Received compound RTCP packet of size " + packet.getLength() + 
+							" from " + packet.getSocketAddress().toString() + " via " + intfStr
+							+ " containing " + compPkt.rtcpPkts.size() + " packets" );
+
+					this.rtpSession.debugAppIntf.packetReceived(1, 
+							(InetSocketAddress) packet.getSocketAddress(), str);
+				} else {
+					String str = new String("Received invalid RTCP packet of size " + packet.getLength() + 
+							" from " + packet.getSocketAddress().toString() + " via " +  intfStr
+							+ ": " + this.debugErrorString(compPkt.problem) );
+
+					this.rtpSession.debugAppIntf.packetReceived(-2, 
+							(InetSocketAddress) packet.getSocketAddress(), str);
+				}
+			}
+			
+			if(RTPSession.rtcpDebugLevel > 5) {
+				Iterator<RtcpPkt> iter = compPkt.rtcpPkts.iterator();
+				String str = " ";
+				while(iter.hasNext()) {
+					RtcpPkt aPkt = iter.next();
+					str += (aPkt.getClass().toString() + ":"+aPkt.itemCount+ ", ");
+				}
+				System.out.println("<-> RTCPReceiverThread.parsePacket() from " + packet.getSocketAddress().toString() + str);
+			}
+			
+
+			//Loop over the information
+			Iterator iter = compPkt.rtcpPkts.iterator();
+
+			long curTime = System.currentTimeMillis();
+
+			while(iter.hasNext()) {
+				RtcpPkt aPkt = (RtcpPkt) iter.next();
+
+				// Our own packets should already have been filtered out.
+				if(aPkt.ssrc == rtpSession.ssrc) {
+					System.out.println("RTCPReceiverThread() received RTCP packet" 
+							+ " with conflicting SSRC from " + packet.getSocketAddress().toString());
+					rtpSession.resolveSsrcConflict();
+					return -1;
+				}
+
+				/**        Receiver Reports        **/
+				if(	aPkt.getClass() == RtcpPktRR.class) {
+					RtcpPktRR rrPkt = (RtcpPktRR) aPkt;
+
+					Participant p = findParticipant(rrPkt.ssrc, packet);
+					p.lastRtcpPkt = curTime;
+
+					if(rtpSession.rtcpAppIntf != null) {
+						rtpSession.rtcpAppIntf.RRPktReceived(rrPkt.ssrc, rrPkt.reporteeSsrc, 
+								rrPkt.lossFraction, rrPkt.lostPktCount, rrPkt.extHighSeqRecv,
+								rrPkt.interArvJitter, rrPkt.timeStampLSR, rrPkt.delaySR);
+					}
+
+					/**        Sender Reports        **/
+				} else if(aPkt.getClass() == RtcpPktSR.class) {
+					RtcpPktSR srPkt = (RtcpPktSR) aPkt;
+
+					Participant p = findParticipant(srPkt.ssrc, packet);
+					p.lastRtcpPkt = curTime;
+
+					if(p != null) {
+
+						if(p.ntpGradient < 0 && p.lastNtpTs1 > -1) {
+							//Calculate gradient NTP vs RTP
+							long newTime = StaticProcs.undoNtpMess(srPkt.ntpTs1, srPkt.ntpTs2);
+							p.ntpGradient = ((double) (newTime - p.ntpOffset))/((double) srPkt.rtpTs - p.lastSRRtpTs);
+							if(RTPSession.rtcpDebugLevel > 4) {
+								System.out.println("RTCPReceiverThread calculated NTP vs RTP gradient: " + Double.toString(p.ntpGradient));
+							}
+						} else {
+							// Calculate sum of ntpTs1 and ntpTs2 in milliseconds
+							p.ntpOffset = StaticProcs.undoNtpMess(srPkt.ntpTs1, srPkt.ntpTs2);
+							p.lastNtpTs1 = srPkt.ntpTs1;
+							p.lastNtpTs2 = srPkt.ntpTs2;
+							p.lastSRRtpTs = srPkt.rtpTs;
+						}
+
+						// For the next RR
+						p.timeReceivedLSR = curTime;
+						p.setTimeStampLSR(srPkt.ntpTs1,srPkt.ntpTs2);
+
+					}
+
+
+					if(rtpSession.rtcpAppIntf != null) {
+						if(srPkt.rReports != null) {
+							rtpSession.rtcpAppIntf.SRPktReceived(srPkt.ssrc, srPkt.ntpTs1, srPkt.ntpTs2, 
+									srPkt.rtpTs, srPkt.sendersPktCount, srPkt.sendersPktCount,
+									srPkt.rReports.reporteeSsrc, srPkt.rReports.lossFraction, srPkt.rReports.lostPktCount,
+									srPkt.rReports.extHighSeqRecv, srPkt.rReports.interArvJitter, srPkt.rReports.timeStampLSR,
+									srPkt.rReports.delaySR);
+						} else {
+							rtpSession.rtcpAppIntf.SRPktReceived(srPkt.ssrc, srPkt.ntpTs1, srPkt.ntpTs2, 
+									srPkt.rtpTs, srPkt.sendersPktCount, srPkt.sendersPktCount,
+									null, null, null,
+									null, null, null,
+									null);
+						}
+					}
+
+					/**        Source Descriptions       **/
+				} else if(aPkt.getClass() == RtcpPktSDES.class) {
+					RtcpPktSDES sdesPkt = (RtcpPktSDES) aPkt;				
+
+					// The the participant database is updated
+					// when the SDES packet is reconstructed by CompRtcpPkt	
+					if(rtpSession.rtcpAppIntf != null) {
+						rtpSession.rtcpAppIntf.SDESPktReceived(sdesPkt.participants);
+					}
+
+					/**        Bye Packets       **/
+				} else if(aPkt.getClass() == RtcpPktBYE.class) {
+					RtcpPktBYE byePkt = (RtcpPktBYE) aPkt;
+
+					long time = System.currentTimeMillis();
+					Participant[] partArray = new Participant[byePkt.ssrcArray.length];
+
+					for(int i=0; i<byePkt.ssrcArray.length; i++) {
+						partArray[i] = rtpSession.partDb.getParticipant(byePkt.ssrcArray[i]);
+						if(partArray[i] != null)
+							partArray[i].timestampBYE = time;
+					}
+
+					if(rtpSession.rtcpAppIntf != null) {
+						rtpSession.rtcpAppIntf.BYEPktReceived(partArray, new String(byePkt.reason));
+					}
+					
+					/**        Application specific Packets       **/
+				} else if(aPkt.getClass() == RtcpPktAPP.class) {
+					RtcpPktAPP appPkt = (RtcpPktAPP) aPkt;
+
+					Participant part = findParticipant(appPkt.ssrc, packet);
+					
+					if(rtpSession.rtcpAppIntf != null) {
+						rtpSession.rtcpAppIntf.APPPktReceived(part, appPkt.itemCount, appPkt.pktName, appPkt.pktData);
+					}
+			}
+
+
+
+			}
+		}
+		return 0;
+	}
+	
+	/**
+	 * Returns a legible message when an error occurs
+	 * 
+	 * @param errorCode the internal error code, commonly negative of packet type
+	 * @return a string that is hopefully somewhat informative
+	 */
+	private String debugErrorString(int errorCode) {
+		String aStr = "";
+		switch(errorCode) {
+			case -1: aStr = "The first packet was not of type SR or RR."; break;
+			case -2: aStr = "The padding bit was set for the first packet."; break;
+			case -200: aStr = " Error parsing Sender Report packet."; break;
+			case -201: aStr = " Error parsing Receiver Report packet."; break;
+			case -202: aStr = " Error parsing SDES packet"; break;
+			case -203: aStr = " Error parsing BYE packet."; break;
+			case -204: aStr = " Error parsing Application specific packet."; break;
+			case -205: aStr = " Error parsing RTP Feedback packet."; break;
+			case -206: aStr = " Error parsing Payload-Specific Feedback packet."; break;
+		default:
+			aStr = "Unknown error code " + errorCode + ".";
+		}
+		
+		return aStr;
+	}
+
+	/**
+	 * Start the RTCP receiver thread.
+	 * 
+	 * It will
+	 * 1) run when it receives a packet 
+	 * 2) parse the packet
+	 * 3) call any relevant callback functions, update database
+	 * 4) block until the next one arrives.
+	 */
+	public void run() {
+		if(RTPSession.rtcpDebugLevel > 1) {
+			if(rtpSession.mcSession) {
+				System.out.println("-> RTCPReceiverThread.run() starting on MC " + rtcpSession.rtcpMCSock.getLocalPort() );
+			} else {
+				System.out.println("-> RTCPReceiverThread.run() starting on " + rtcpSession.rtcpSock.getLocalPort() );
+			}
+		}
+
+		while(!rtpSession.endSession) {
+			
+			if(RTPSession.rtcpDebugLevel > 4) {
+				if(rtpSession.mcSession) {
+					System.out.println("-> RTCPReceiverThread.run() waiting for packet on MC " + rtcpSession.rtcpMCSock.getLocalPort() );
+				} else {
+					System.out.println("-> RTCPReceiverThread.run() waiting for packet on " + rtcpSession.rtcpSock.getLocalPort() );
+				}
+			}
+
+			// Prepare a packet
+			byte[] rawPkt = new byte[1500];
+			DatagramPacket packet = new DatagramPacket(rawPkt, rawPkt.length);
+
+			// Wait for it to arrive
+			if(! rtpSession.mcSession) {
+				//Unicast
+				try {
+					rtcpSession.rtcpSock.receive(packet);
+				} catch (IOException e) {
+					if(!rtpSession.endSession) {
+						e.printStackTrace();
+					} else {
+						continue;
+					}
+				}
+			} else {
+				//Multicast
+				try {
+					rtcpSession.rtcpMCSock.receive(packet);
+				} catch (IOException e) {
+					if(!rtpSession.endSession) {
+						e.printStackTrace();
+					} else {
+						continue;
+					}
+				}
+			}
+			
+			// Check whether this is one of our own
+			if( (rtpSession.mcSession && ! packet.getSocketAddress().equals(rtcpSession.rtcpMCSock) )
+					|| ! packet.getSocketAddress().equals(rtcpSession.rtcpSock) ) {
+				//System.out.println("Packet received from: " + packet.getSocketAddress().toString());
+				parsePacket(packet);
+				//rtpSession.partDb.debugPrint();
+			}			
+		}
+		
+		if(RTPSession.rtcpDebugLevel > 1) {
+			System.out.println("<-> RTCPReceiverThread terminating");
+		}
+	}
+
+}