1 files changed, 166 insertions, 0 deletions
diff --git a/src/IvyWatcher.java b/src/IvyWatcher.java
new file mode 100755
index 0000000..21311e9
--- /dev/null
+++ b/src/IvyWatcher.java
@@ -0,0 +1,166 @@
+/*
+*
+* IvyWatcher : gestion des messages UDP pour annoncer les arrivées 
+*
+*/
+package fr.dgac.ivy ;
+
+import java.lang.Thread;
+import java.net.*;
+import java.io.*;
+import java.util.StringTokenizer;
+import gnu.regexp.*;
+import java.util.Vector;
+public class IvyWatcher extends Thread {
+  Ivy  bus; /* master bus controler */
+  DatagramSocket broadcast; /* supervision socket */
+  private Vector domainaddrList;
+  private static boolean debug = (System.getProperty("IVY_DEBUG")!=null);
+  
+  public void close() {
+    broadcast.close();
+  }
+  private void sendBroadcast( String data, String net ) throws IvyException
+  {
+	DatagramPacket packet;
+	// transformation en forme de broadcast w.x.y.z en w.x.y.255
+	try {
+		// simple trick to expend to 255 thank's Alex
+	net += ".255.255.255";
+	RE exp = new RE( "^(\\d+\\.\\d+\\.\\d+\\.\\d+).*");
+	net = exp.substitute( net , "$1" );
+	} catch ( REException e ){
+		throw new IvyException("Bad broascat addr");
+	}
+	// broadcast sur l'adresse iadr
+    try {
+	  InetAddress iaddr = InetAddress.getByName(net);
+	  domainaddrList.addElement( iaddr );
+	  packet = new DatagramPacket(
+		      data.getBytes(),
+		      data.length(),
+		      iaddr,
+		      broadcast.getLocalPort() );
+      broadcast.send( packet );
+    } catch ( UnknownHostException e ) {
+      throw new IvyException("Broadcast sur réseau inconnu " + e );
+    } catch ( IOException e ) {
+      throw new IvyException("broadcast send erreur " + e );
+    }
+  }
+  public void sendStart(String domain) throws IvyException {
+	String domainaddr;
+	// parse Domain to get port number
+	int port;
+	  int sep_index = domain.lastIndexOf( ":" );
+	  if ( sep_index == -1 )
+		{
+		  port = bus.DEFAULT_PORT;
+		  domainaddr = domain;
+		}
+	  else 
+	  { 
+		  port = Integer.parseInt( domain.substring( sep_index +1 ));
+		  domainaddr = domain.substring(0,sep_index);
+	  }
+	// create the UDP socket
+	try {
+      broadcast = new MulticastSocket(port );
+    } catch ( IOException e ) {
+      throw new IvyException("IvyWatcher erreur I/O" + e );
+    }
+	// start UDP receiver
+    start();
+	// send hello world on UDP sockets
+	String hello = "3 "+bus.getApplicationPort()+"\n";
+	StringTokenizer st = new StringTokenizer(domainaddr," \t:,");
+    while  ( st.hasMoreTokens()) {
+    sendBroadcast( hello, st.nextToken() );
+	}
+  }
+  
+  IvyWatcher(Ivy bus) throws IvyException {
+    this.bus = bus;
+    domainaddrList = new Vector();
+  }
+  
+  public void run() {
+    DatagramPacket packet;
+    byte buf[] = new byte[256];
+    int port;
+    int version;
+    /**/
+    traceDebug("IvyWatcher waiting for Broadcast");
+    while( bus.ivyRunning() )
+	{
+    try {
+	    /* receive antoher application port */
+        packet = new DatagramPacket(buf, 256);
+        broadcast.receive( packet );
+        String msg = new String(packet.getData()) ;
+		InetAddress remotehost = packet.getAddress();
+        traceDebug("BUSWATCHER Receive Broadcast from:"+
+				   remotehost.getHostName()+
+				   ":"+packet.getPort()
+				   +"'"+msg+"'");
+		//  check if remoteaddr is in our broadcast domain list
+		if ( !isInDomain( remotehost ) )
+			continue;
+        StringTokenizer st = new StringTokenizer(msg);
+        if  ( ! st.hasMoreTokens()) {
+          System.err.println("Bad format "+msg);
+          continue;
+        }
+        version  = Integer.parseInt( st.nextToken() );
+        if  ( ! st.hasMoreTokens()) {
+          System.err.println("Bad format "+msg);
+          continue;
+        }
+        port = Integer.parseInt( st.nextToken() );
+		// TODO: More checking  here host port domain etc....
+        if ( (bus.getApplicationPort() == port) )
+		{
+			continue;
+		}
+        traceDebug("BUSWATCHER Broadcast de "
+	    +packet.getAddress().getHostName()+":"+packet.getPort()+" port "+port);
+          /* connect to the application */
+          try {
+            Socket socket = new Socket( remotehost, port );
+            bus.addClient( socket );
+          } catch ( UnknownHostException e ) {
+            System.err.println("Unkonwn host "+remotehost);
+          } catch ( IOException e) {
+            System.err.println("can't connect to "+remotehost+" port "+port);
+          }
+	
+    } catch (  IOException e ) {
+		// TODO: comment distinger la fin normale de 'erreur
+      /* fermeture de la socket arret normal */
+      traceDebug("Error IvyWatcher exception:  "  +  e.getMessage());
+    }
+	}// end while
+  }
+  
+  private void traceDebug(String s){
+    if (debug) System.out.println("-->ivywatcher<-- "+s);
+  }
+  private boolean isInDomain( InetAddress host ){
+	  byte rem_addr[] = host.getAddress();
+	  for ( int i = 0 ; i < domainaddrList.size(); i++ )
+	  {
+		  byte addr[] = ((InetAddress)domainaddrList.elementAt(i)).getAddress();
+		  int j ;
+		  for (  j = 0 ; j < 4 ; j++  )
+			  if ( (addr[j] != -1) && (addr[j] != rem_addr[j]) ) break;
+		  if ( j == 4 ) 
+			{
+			  traceDebug( "host " + host + " is in domain\n" );
+			  return true;
+		    }
+	  }
+	  traceDebug( "host " + host + " Not in domain\n" );
+	  return false;
+  }
+}
+