--- loncom/lond	2003/09/15 10:03:52	1.143
+++ loncom/lond	2003/09/23 11:23:31	1.147
@@ -2,7 +2,7 @@
 # The LearningOnline Network
 # lond "LON Daemon" Server (port "LOND" 5663)
 #
-# $Id: lond,v 1.143 2003/09/15 10:03:52 foxr Exp $
+# $Id: lond,v 1.147 2003/09/23 11:23:31 foxr Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -60,6 +60,25 @@
 # 09/08/2003 Ron Fox:  Told lond to take care of change logging so we
 #      don't have to remember it:
 # $Log: lond,v $
+# Revision 1.147  2003/09/23 11:23:31  foxr
+# Comlplete implementation of reinit functionality.  Must still implement
+# the actual initialization functionality, but the process can now
+# receive the request and either invoke the appropriate internal function or
+# signal the correct lonc.
+#
+# Revision 1.146  2003/09/16 10:28:14  foxr
+# ReinitProcess - decode the process selector and produce the associated pid
+# filename.  Note: While it is possible to test that valid process selectors are
+# handled properly I am not able to test that invalid process selectors produce
+# the appropriate error as lonManage also blocks the use of invalid process selectors.
+#
+# Revision 1.145  2003/09/16 10:13:20  foxr
+# Added ReinitProcess function to oversee the parsing and processing of the
+# reinit:<process> client request.
+#
+# Revision 1.144  2003/09/16 09:47:01  foxr
+# Added skeletal support for SIGUSR2 (update hosts.tab)
+#
 # Revision 1.143  2003/09/15 10:03:52  foxr
 # Completed and tested code for pushfile.
 #
@@ -97,7 +116,7 @@ my $DEBUG = 0;		       # Non zero to ena
 my $status='';
 my $lastlog='';
 
-my $VERSION='$Revision: 1.143 $'; #' stupid emacs
+my $VERSION='$Revision: 1.147 $'; #' stupid emacs
 my $remoteVERSION;
 my $currenthostid;
 my $currentdomainid;
@@ -335,7 +354,7 @@ sub PushFile {
 
     if(!InstallFile($tablefile, $contents)) {
 	&logthis('<font color="red"> Pushfile: unable to install '
-		 .$tablefile." $! </font>");
+	 .$tablefile." $! </font>");
 	return "error:$!";
     }
     else {
@@ -350,6 +369,53 @@ sub PushFile {
     return "ok";
 
 }
+
+#
+#  Called to re-init either lonc or lond.
+#
+#  Parameters:
+#    request   - The full request by the client.  This is of the form
+#                reinit:<process>  
+#                where <process> is allowed to be either of 
+#                lonc or lond
+#
+#  Returns:
+#     The string to be sent back to the client either:
+#   ok         - Everything worked just fine.
+#   error:why  - There was a failure and why describes the reason.
+#
+#
+sub ReinitProcess {
+    my $request = shift;
+
+
+    # separate the request (reinit) from the process identifier and
+    # validate it producing the name of the .pid file for the process.
+    #
+    #
+    my ($junk, $process) = split(":", $request);
+    my $processpidfile = $perlvar{'lonDaemons'}.'/logs/';
+    if($process eq 'lonc') {
+	$processpidfile = $processpidfile."lonc.pid";
+	if (!open(PIDFILE, "< $processpidfile")) {
+	    return "error:Open failed for $processpidfile";
+	}
+	my $loncpid = <PIDFILE>;
+	close(PIDFILE);
+	logthis('<font color="red"> Reinitializing lonc pid='.$loncpid
+		."</font>");
+	kill("USR2", $loncpid);
+    } elsif ($process eq 'lond') {
+	logthis('<font color="red"> Reinitializing self (lond) </font>');
+	&UpdateHosts;			# Lond is us!!
+    } else {
+	&logthis('<font color="yellow" Invalid reinit request for '.$process
+		 ."</font>");
+	return "error:Invalid process identifier $process";
+    }
+    return 'ok';
+}
+
 #
 #  Convert an error return code from lcpasswd to a string value.
 #
@@ -485,6 +551,20 @@ sub HUPSMAN {                      # sig
     exec("$execdir/lond");         # here we go again
 }
 
+#
+#   Called in response to a USR2 signal.
+#   - Reread hosts.tab
+#   - All children connected to hosts that were removed from hosts.tab
+#     are killed via SIGINT
+#   - All children connected to previously existing hosts are sent SIGUSR1
+#   - Our internal hosts hash is updated to reflect the new contents of
+#     hosts.tab causing connections from hosts added to hosts.tab to
+#     now be honored.
+#
+sub UpdateHosts {
+    logthis('<font color="blue"> Updating connections </font>');
+}
+
 sub checkchildren {
     &initnewstatus();
     &logstatus();
@@ -727,7 +807,7 @@ $SIG{CHLD} = \&REAPER;
 $SIG{INT}  = $SIG{TERM} = \&HUNTSMAN;
 $SIG{HUP}  = \&HUPSMAN;
 $SIG{USR1} = \&checkchildren;
-
+$SIG{USR2} = \&UpdateHosts;
 
 
 # --------------------------------------------------------------
@@ -936,7 +1016,9 @@ sub make_new_child {
 		       if ($wasenc == 1) {
 			   my $cert = GetCertificate($userinput);
 			   if(ValidManager($cert)) {
-			       print $client "ok\n";
+			       chomp($userinput);
+			       my $reply = ReinitProcess($userinput);
+			       print $client  "$reply\n";
 			   } else {
 			       print $client "refused\n";
 			   }
@@ -2501,6 +2583,17 @@ each connection is logged.
 
 =item *
 
+SIGUSR2
+
+Parent Signal assignment:
+    $SIG{USR2} = \&UpdateHosts
+
+Child signal assignment:
+    NONE
+
+
+=item *
+
 SIGCHLD
 
 Parent signal assignment: