Diff for /loncom/loncnew between versions 1.7 and 1.64

version 1.7, 2003/06/03 01:59:39 version 1.64, 2004/10/05 10:10:31
Line 7 Line 7
 # Copyright Michigan State University Board of Trustees  # Copyright Michigan State University Board of Trustees
 #  #
 # This file is part of the LearningOnline Network with CAPA (LON-CAPA).  # This file is part of the LearningOnline Network with CAPA (LON-CAPA).
 #  ## LON-CAPA is free software; you can redistribute it and/or modify
 # LON-CAPA is free software; you can redistribute it and/or modify  
 # it under the terms of the GNU General Public License as published by  # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation; either version 2 of the License, or  # the Free Software Foundation; either version 2 of the License, or
 # (at your option) any later version.  # (at your option) any later version.
Line 27 Line 26
 # http://www.lon-capa.org/  # http://www.lon-capa.org/
 #  #
 #  #
 # new lonc handles n requestors spread out bver m connections to londs.  # new lonc handles n request out bver m connections to londs.
 # This module is based on the Event class.  # This module is based on the Event class.
 #   Development iterations:  #   Development iterations:
 #    - Setup basic event loop.   (done)  #    - Setup basic event loop.   (done)
Line 36 Line 35
 #    - Add ability to create/negotiate lond connections (done).  #    - Add ability to create/negotiate lond connections (done).
 #    - Add general logic for dispatching requests and timeouts. (done).  #    - Add general logic for dispatching requests and timeouts. (done).
 #    - Add support for the lonc/lond requests.          (done).  #    - Add support for the lonc/lond requests.          (done).
 #    - Add logging/status monitoring.  #    - Add logging/status monitoring.                    (done)
 #    - Add Signal handling - HUP restarts. USR1 status report.  #    - Add Signal handling - HUP restarts. USR1 status report. (done)
 #    - Add Configuration file I/O                       (done).  #    - Add Configuration file I/O                       (done).
 #    - Add Pending request processing on startup.  #    - Add management/status request interface.         (done)
 #    - Add management/status request interface.  #    - Add deferred request capability.                  (done)
 #    - Add deferred request capability.  #    - Detect transmission timeouts.                     (done)
 #  
   
 # Change log:  
 #    $Log$  
 #    Revision 1.7  2003/06/03 01:59:39  foxr  
 #    complete coding to support deferred transactions.  
 #  
 #  #
   
   use strict;
 use lib "/home/httpd/lib/perl/";  use lib "/home/httpd/lib/perl/";
 use lib "/home/foxr/newloncapa/types";  
 use Event qw(:DEFAULT );  use Event qw(:DEFAULT );
 use POSIX qw(:signal_h);  use POSIX qw(:signal_h);
   use POSIX;
 use IO::Socket;  use IO::Socket;
 use IO::Socket::INET;  use IO::Socket::INET;
 use IO::Socket::UNIX;  use IO::Socket::UNIX;
   use IO::File;
 use IO::Handle;  use IO::Handle;
 use Socket;  use Socket;
 use Crypt::IDEA;  use Crypt::IDEA;
Line 68  use LONCAPA::LondTransaction; Line 62  use LONCAPA::LondTransaction;
 use LONCAPA::Configuration;  use LONCAPA::Configuration;
 use LONCAPA::HashIterator;  use LONCAPA::HashIterator;
   
 print "Loncnew starting\n";  
   
 #  
 #   Disable all signals we might receive from outside for now.  
 #  
 $SIG{QUIT}  = IGNORE;  
 $SIG{HUP}   = IGNORE;  
 $SIG{USR1}  = IGNORE;  
 $SIG{INT}   = IGNORE;  
 $SIG{CHLD}  = IGNORE;  
 $SIG{__DIE__}  = IGNORE;  
   
   
 # Read the httpd configuration file to get perl variables  # Read the httpd configuration file to get perl variables
 # normally set in apache modules:  # normally set in apache modules:
Line 91  my %perlvar    = %{$perlvarref}; Line 73  my %perlvar    = %{$perlvarref};
 #  parent and shared variables.  #  parent and shared variables.
   
 my %ChildHash; # by pid -> host.  my %ChildHash; # by pid -> host.
   my %HostToPid; # By host -> pid.
   my %HostHash; # by loncapaname -> IP.
   my %listening_to; # Socket->host table for who the parent
                                   # is listening to.
   my %parent_dispatchers;         # host-> listener watcher events. 
   
   my $MaxConnectionCount = 10; # Will get from config later.
 my $MaxConnectionCount = 5; # Will get from config later.  
 my $ClientConnection = 0; # Uniquifier for client events.  my $ClientConnection = 0; # Uniquifier for client events.
   
 my $DebugLevel = 5;  my $DebugLevel = 0;
 my $IdleTimeout= 3600; # Wait an hour before pruning connections.  my $NextDebugLevel= 2; # So Sigint can toggle this.
   my $IdleTimeout= 600; # Wait 10 minutes before pruning connections.
   
   my $LogTransactions = 0; # When True, all transactions/replies get logged.
   
 #  #
 #  The variables below are only used by the child processes.  #  The variables below are only used by the child processes.
 #  #
 my $RemoteHost; # Name of host child is talking to.  my $RemoteHost; # Name of host child is talking to.
 my $UnixSocketDir= "/home/httpd/sockets";   my $UnixSocketDir= $perlvar{'lonSockDir'};
 my $IdleConnections = Stack->new(); # Set of idle connections  my $IdleConnections = Stack->new(); # Set of idle connections
 my %ActiveConnections; # Connections to the remote lond.  my %ActiveConnections; # Connections to the remote lond.
 my %ActiveTransactions; # LondTransactions in flight.  my %ActiveTransactions; # LondTransactions in flight.
 my %ActiveClients; # Serial numbers of active clients by socket.  my %ActiveClients; # Serial numbers of active clients by socket.
 my $WorkQueue       = Queue->new(); # Queue of pending transactions.  my $WorkQueue       = Queue->new(); # Queue of pending transactions.
 #  my $ClientQueue     = Queue->new(); # Queue of clients causing xactinos.  
 my $ConnectionCount = 0;  my $ConnectionCount = 0;
 my $IdleSeconds     = 0; # Number of seconds idle.  my $IdleSeconds     = 0; # Number of seconds idle.
   my $Status          = ""; # Current status string.
   my $RecentLogEntry  = "";
   my $ConnectionRetries=2; # Number of connection retries allowed.
   my $ConnectionRetriesLeft=2; # Number of connection retries remaining.
   my $LondVersion     = "unknown"; # Version of lond we talk with.
   my $KeyMode         = "";       # e.g. ssl, local, insecure from last connect.
   my $LondConnecting  = 0;       # True when a connection is being built.
   
   
   # DO NOT SET THE NEXT VARIABLE TO NON ZERO!!!!!!!!!!!!!!!
   
   my $DieWhenIdle     = 0; # When true children die when trimmed -> 0.
   my $I_am_child      = 0; # True if this is the child process.
   
   #
   #   The hash below gives the HTML format for log messages
   #   given a severity.
   #    
   my %LogFormats;
   
   $LogFormats{"CRITICAL"} = "<font color='red'>CRITICAL: %s</font>";
   $LogFormats{"SUCCESS"}  = "<font color='green'>SUCCESS: %s</font>";
   $LogFormats{"INFO"}     = "<font color='yellow'>INFO: %s</font>";
   $LogFormats{"WARNING"}  = "<font color='blue'>WARNING: %s</font>";
   $LogFormats{"DEFAULT"}  = " %s ";
   
   
   #  UpdateStatus;
   #    Update the idle status display to show how many connections
   #    are left, retries and other stuff.
   #
   sub UpdateStatus {
       if ($ConnectionRetriesLeft > 0) {
    ShowStatus(GetServerHost()." Connection count: ".$ConnectionCount
      ." Retries remaining: ".$ConnectionRetriesLeft
      ." ($KeyMode)");
       } else {
    ShowStatus(GetServerHost()." >> DEAD <<");
       }
   }
   
 #  
 #   This disconnected socket makes posible a bit more regular  
 #   code when processing delayed requests:  
 #  
 my $NullSocket = IO::Socket->new();  
   
 #  =pod
   
   =head2 LogPerm
   
   Makes an entry into the permanent log file.
   
   =cut
   sub LogPerm {
       my $message=shift;
       my $execdir=$perlvar{'lonDaemons'};
       my $now=time;
       my $local=localtime($now);
       my $fh=IO::File->new(">>$execdir/logs/lonnet.perm.log");
       print $fh "$now:$message:$local\n";
   }
   
   =pod
   
   =head2 Log
   
   Logs a message to the log file.
   Parameters:
   
   =item severity
   
   One of CRITICAL, WARNING, INFO, SUCCESS used to select the
   format string used to format the message.  if the severity is
   not a defined severity the Default format string is used.
   
   =item message
   
   The base message.  In addtion to the format string, the message
   will be appended to a string containing the name of our remote
   host and the time will be formatted into the message.
   
   =cut
   
   sub Log {
   
       my ($severity, $message) = @_;
   
       if(!$LogFormats{$severity}) {
    $severity = "DEFAULT";
       }
   
       my $format = $LogFormats{$severity};
       
       #  Put the window dressing in in front of the message format:
   
       my $now   = time;
       my $local = localtime($now);
       my $finalformat = "$local ($$) [$RemoteHost] [$Status] ";
       my $finalformat = $finalformat.$format."\n";
   
       # open the file and put the result.
   
       my $execdir = $perlvar{'lonDaemons'};
       my $fh      = IO::File->new(">>$execdir/logs/lonc.log");
       my $msg = sprintf($finalformat, $message);
       $RecentLogEntry = $msg;
       print $fh $msg;
       
       
   }
   
   
 =pod  =pod
   
Line 130  Returns the name of the host that a sock Line 217  Returns the name of the host that a sock
 =cut  =cut
   
 sub GetPeername {  sub GetPeername {
     my $connection = shift;  
     my $AdrFamily  = shift;  
       my ($connection, $AdrFamily) = @_;
   
     my $peer       = $connection->peername();      my $peer       = $connection->peername();
     my $peerport;      my $peerport;
     my $peerip;      my $peerip;
     if($AdrFamily == AF_INET) {      if($AdrFamily == AF_INET) {
  ($peerport, $peerip) = sockaddr_in($peer);   ($peerport, $peerip) = sockaddr_in($peer);
  my $peername    = gethostbyaddr($iaddr, $AdrFamily);   my $peername    = gethostbyaddr($peerip, $AdrFamily);
  return $peername;   return $peername;
     } elsif ($AdrFamily == AF_UNIX) {      } elsif ($AdrFamily == AF_UNIX) {
  my $peerfile;   my $peerfile;
Line 145  sub GetPeername { Line 234  sub GetPeername {
  return $peerfile;   return $peerfile;
     }      }
 }  }
 #----------------------------- Timer management ------------------------  
 =pod  =pod
   
 =head2 Debug  =head2 Debug
Line 155  Invoked to issue a debug message. Line 243  Invoked to issue a debug message.
 =cut  =cut
   
 sub Debug {  sub Debug {
     my $level   = shift;  
     my $message = shift;      my ($level, $message) = @_;
   
     if ($level <= $DebugLevel) {      if ($level <= $DebugLevel) {
  print $message." host = ".$RemoteHost."\n";   Log("INFO", "-Debug- $message host = $RemoteHost");
     }      }
 }  }
   
 sub SocketDump {  sub SocketDump {
     my $level = shift;  
     my $socket= shift;      my ($level, $socket) = @_;
   
     if($level <= $DebugLevel) {      if($level <= $DebugLevel) {
  $socket->Dump();   $socket->Dump(-1); # Ensure it will get dumped.
     }      }
 }  }
   
Line 175  sub SocketDump { Line 265  sub SocketDump {
 =head2 ShowStatus  =head2 ShowStatus
   
  Place some text as our pid status.   Place some text as our pid status.
    and as what we return in a SIGUSR1
   
 =cut  =cut
 sub ShowStatus {  sub ShowStatus {
     my $status = shift;      my $state = shift;
     $0 =  "lonc: ".$status;      my $now = time;
       my $local = localtime($now);
       $Status   = $local.": ".$state;
       $0='lonc: '.$state.' '.$local;
   }
   
   =pod
   
   =head 2 SocketTimeout
   
       Called when an action on the socket times out.  The socket is 
      destroyed and any active transaction is failed.
   
   
   =cut
   sub SocketTimeout {
       my $Socket = shift;
       Log("WARNING", "A socket timeout was detected");
       Debug(5, " SocketTimeout called: ");
       $Socket->Dump(0);
       if(exists($ActiveTransactions{$Socket})) {
    FailTransaction($ActiveTransactions{$Socket});
       }
       KillSocket($Socket); # A transaction timeout also counts as
                                   # a connection failure:
       $ConnectionRetriesLeft--;
       if($ConnectionRetriesLeft <= 0) {
    Log("CRITICAL", "Host marked DEAD: ".GetServerHost());
    $LondConnecting = 0;
       }
   
 }  }
   #
   #   This function should be called by the child in all cases where it must
   #   exit.  If the child process is running with the DieWhenIdle turned on
   #   it must create a lock file for the AF_UNIX socket in order to prevent
   #   connection requests from lonnet in the time between process exit
   #   and the parent picking up the listen again.
   # Parameters:
   #     exit_code           - Exit status value, however see the next parameter.
   #     message             - If this optional parameter is supplied, the exit
   #                           is via a die with this message.
   #
   sub child_exit {
       my ($exit_code, $message) = @_;
   
       # Regardless of how we exit, we may need to do the lock thing:
   
       if($DieWhenIdle) {
    #
    #  Create a lock file since there will be a time window
    #  between our exit and the parent's picking up the listen
    #  during which no listens will be done on the
    #  lonnet client socket.
    #
    my $lock_file = GetLoncSocketPath().".lock";
    open(LOCK,">$lock_file");
    print LOCK "Contents not important";
    close(LOCK);
   
    exit(0);
       }
       #  Now figure out how we exit:
   
       if($message) {
    die $message;
       } else {
    exit($exit_code);
       }
   }
   #----------------------------- Timer management ------------------------
   
 =pod  =pod
   
Line 192  Invoked  each timer tick. Line 352  Invoked  each timer tick.
   
   
 sub Tick {  sub Tick {
       my ($Event)       = @_;
       my $clock_watcher = $Event->w;
   
     my $client;      my $client;
     ShowStatus(GetServerHost()." Connection count: ".$ConnectionCount);      UpdateStatus();
     Debug(6, "Tick");  
     Debug(6, "    Current connection count: ".$ConnectionCount);  
     foreach $client (keys %ActiveClients) {  
  Debug(7, "    Have client:  with id: ".$ActiveClients{$client});  
     }  
     # Is it time to prune connection count:      # Is it time to prune connection count:
   
   
Line 206  sub Tick { Line 365  sub Tick {
        ($WorkQueue->Count() == 0)) { # Idle connections and nothing to do?         ($WorkQueue->Count() == 0)) { # Idle connections and nothing to do?
  $IdleSeconds++;   $IdleSeconds++;
  if($IdleSeconds > $IdleTimeout) { # Prune a connection...   if($IdleSeconds > $IdleTimeout) { # Prune a connection...
     $Socket = $IdleConnections->pop();      my $Socket = $IdleConnections->pop();
     KillSocket($Socket);      KillSocket($Socket);
       $IdleSeconds = 0; # Otherwise all connections get trimmed to fast.
       UpdateStatus();
       if(($ConnectionCount == 0) && $DieWhenIdle) {
    &child_exit(0);
   
       }
  }   }
     } else {      } else {
  $IdleSeconds = 0; # Reset idle count if not idle.   $IdleSeconds = 0; # Reset idle count if not idle.
     }      }
       #
       #  For each inflight transaction, tick down its timeout counter.
       #
   
       foreach my $item (keys %ActiveConnections) {
    my $State = $ActiveConnections{$item}->data->GetState();
    if ($State ne 'Idle') {
       Debug(5,"Ticking Socket $State $item");
       $ActiveConnections{$item}->data->Tick();
    }
       }
     # Do we have work in the queue, but no connections to service them?      # Do we have work in the queue, but no connections to service them?
     # If so, try to make some new connections to get things going again.      # If so, try to make some new connections to get things going again.
     #      #
           #   Note this code is dead now...
       #
     my $Requests = $WorkQueue->Count();      my $Requests = $WorkQueue->Count();
     if (($ConnectionCount == 0)  && ($Requests > 0)) {      if (($ConnectionCount == 0)  && ($Requests > 0) && (!$LondConnecting)) { 
  my $Connections = ($Requests <= $MaxConnectionCount) ?   if ($ConnectionRetriesLeft > 0) {
                            $Requests : $MaxConnectionCount;      Debug(5,"Work but no connections, Make a new one");
  Debug(1,"Work but no connections, starting ".$Connections." of them");      my $success;
  for ($i =0; $i < $Connections; $i++) {      $success    = &MakeLondConnection;
     MakeLondConnection();      if($success == 0) { # All connections failed:
    Debug(5,"Work in queue failed to make any connectiouns\n");
    EmptyQueue(); # Fail pending transactions with con_lost.
    CloseAllLondConnections(); # Should all be closed but....
       }
    } else {
       $LondConnecting = 0;
       ShowStatus(GetServerHost()." >>> DEAD!!! <<<");
       Debug(5,"Work in queue, but gave up on connections..flushing\n");
       EmptyQueue(); # Connections can't be established.
       CloseAllLondConnections(); # Should all already be closed but...
  }   }
                 
     }      }
       if ($ConnectionCount == 0) {
    $KeyMode = ""; 
    $clock_watcher->cancel();
       }
 }  }
   
 =pod  =pod
Line 247  Trigger disconnections of idle sockets. Line 437  Trigger disconnections of idle sockets.
   
 sub SetupTimer {  sub SetupTimer {
     Debug(6, "SetupTimer");      Debug(6, "SetupTimer");
     Event->timer(interval => 1, debug => 1, cb => \&Tick );      Event->timer(interval => 1, cb => \&Tick );
 }  }
   
 =pod  =pod
Line 267  long enough, it will be shut down and re Line 457  long enough, it will be shut down and re
   
 sub ServerToIdle {  sub ServerToIdle {
     my $Socket   = shift; # Get the socket.      my $Socket   = shift; # Get the socket.
       $KeyMode = $Socket->{AuthenticationMode};
     delete($ActiveTransactions{$Socket}); # Server has no transaction      delete($ActiveTransactions{$Socket}); # Server has no transaction
   
     &Debug(6, "Server to idle");      &Debug(5, "Server to idle");
   
     #  If there's work to do, start the transaction:      #  If there's work to do, start the transaction:
   
     $reqdata = $WorkQueue->dequeue(); # This is a LondTransaction      my $reqdata = $WorkQueue->dequeue(); # This is a LondTransaction
     unless($reqdata eq undef)  {      if ($reqdata ne undef)  {
  Debug(9, "Queue gave request data: ".$reqdata->getRequest());   Debug(5, "Queue gave request data: ".$reqdata->getRequest());
  &StartRequest($Socket,  $reqdata);   &StartRequest($Socket,  $reqdata);
   
     } else {      } else {
   
     #  There's no work waiting, so push the server to idle list.      #  There's no work waiting, so push the server to idle list.
  &Debug(8, "No new work requests, server connection going idle");   &Debug(5, "No new work requests, server connection going idle");
  $IdleConnections->push($Socket);   $IdleConnections->push($Socket);
     }      }
 }  }
Line 326  sub ClientWritable { Line 518  sub ClientWritable {
  # request.   # request.
   
  &Debug(9,"Send result is ".$result." Defined: ".defined($result));   &Debug(9,"Send result is ".$result." Defined: ".defined($result));
  if(defined($result)) {   if($result ne undef) {
     &Debug(9, "send result was defined");      &Debug(9, "send result was defined");
     if($result == length($Data)) { # Entire string sent.      if($result == length($Data)) { # Entire string sent.
  &Debug(9, "ClientWritable data all written");   &Debug(9, "ClientWritable data all written");
Line 344  sub ClientWritable { Line 536  sub ClientWritable {
   
     } else { # Partial string sent.      } else { # Partial string sent.
  $Watcher->data(substr($Data, $result));   $Watcher->data(substr($Data, $result));
    if($result == 0) {    # client hung up on us!!
       # Log("INFO", "lonc pipe client hung up on us!");
       $Watcher->cancel;
       $Socket->shutdown(2);
       $Socket->close();
    }
     }      }
           
  } else { # Error of some sort...   } else { # Error of some sort...
Line 391  The transaction that is being completed. Line 589  The transaction that is being completed.
 =cut  =cut
   
 sub CompleteTransaction {  sub CompleteTransaction {
     &Debug(6,"Complete transaction");      &Debug(5,"Complete transaction");
     my $Socket = shift;  
     my $Transaction = shift;      my ($Socket, $Transaction) = @_;
   
     if (!$Transaction->isDeferred()) { # Normal transaction      if (!$Transaction->isDeferred()) { # Normal transaction
  my $data   = $Socket->GetReply(); # Data to send.   my $data   = $Socket->GetReply(); # Data to send.
    if($LogTransactions) {
       Log("SUCCESS", "Reply from lond: '$data'");
    }
  StartClientReply($Transaction, $data);   StartClientReply($Transaction, $data);
     } else { # Delete deferred transaction file.      } else { # Delete deferred transaction file.
    Log("SUCCESS", "A delayed transaction was completed");
    LogPerm("S:$Transaction->getClient() :".$Transaction->getRequest());
  unlink $Transaction->getFile();   unlink $Transaction->getFile();
     }      }
 }  }
   
 =pod  =pod
   
 =head1 StartClientReply  =head1 StartClientReply
   
    Initiates a reply to a client where the reply data is a parameter.     Initiates a reply to a client where the reply data is a parameter.
Line 418  sub CompleteTransaction { Line 623  sub CompleteTransaction {
     The data to send to apached client.      The data to send to apached client.
   
 =cut  =cut
   
 sub StartClientReply {  sub StartClientReply {
     my $Transaction   = shift;  
     my $data     = shift;      my ($Transaction, $data) = @_;
   
     my $Client   = $Transaction->getClient();      my $Client   = $Transaction->getClient();
   
     &Debug(8," Reply was: ".$data);      &Debug(8," Reply was: ".$data);
     my $Serial         = $ActiveClients{$Client};      my $Serial         = $ActiveClients{$Client};
     my $desc           = sprintf("Connection to lonc client %d",      my $desc           = sprintf("Connection to lonc client %d",
   
  $Serial);   $Serial);
     Event->io(fd       => $Client,      Event->io(fd       => $Client,
       poll     => "w",        poll     => "w",
Line 435  sub StartClientReply { Line 640  sub StartClientReply {
       cb       => \&ClientWritable,        cb       => \&ClientWritable,
       data     => $data);        data     => $data);
 }  }
   
 =pod  =pod
   
 =head2 FailTransaction  =head2 FailTransaction
   
   Finishes a transaction with failure because the associated lond socket    Finishes a transaction with failure because the associated lond socket
Line 445  sub StartClientReply { Line 652  sub StartClientReply {
   - The transaction is 'live' in which case we initiate the sending    - The transaction is 'live' in which case we initiate the sending
     of "con_lost" to the client.      of "con_lost" to the client.
   
 Deleting the transaction means killing it from the   Deleting the transaction means killing it from the %ActiveTransactions hash.
 %ActiveTransactions hash.  
   
 Parameters:  Parameters:
   
Line 454  Parameters: Line 660  Parameters:
     
    The LondTransaction we are failing.     The LondTransaction we are failing.
     
   
 =cut  =cut
   
 sub FailTransaction {  sub FailTransaction {
     my $transaction = shift;      my $transaction = shift;
     my $Lond        = $transaction->getServer();      
     if (!$client->isDeferred()) { # If the transaction is deferred we'll get to it.      #  If the socket is dead, that's already logged.
  my $client  = $transcation->getClient();  
  StartClientReply($client, "con_lost");      if ($ConnectionRetriesLeft > 0) {
    Log("WARNING", "Failing transaction "
       .$transaction->getRequest());
       }
       Debug(1, "Failing transaction: ".$transaction->getRequest());
       if (!$transaction->isDeferred()) { # If the transaction is deferred we'll get to it.
    my $client  = $transaction->getClient();
    Debug(1," Replying con_lost to ".$transaction->getRequest());
    StartClientReply($transaction, "con_lost\n");
     }      }
 # not needed, done elsewhere if active.  
 #    delete $ActiveTransactions{$Lond};  
   
 }  }
   
Line 476  sub FailTransaction { Line 689  sub FailTransaction {
   
 =cut  =cut
 sub EmptyQueue {  sub EmptyQueue {
       $ConnectionRetriesLeft--; # Counts as connection failure too.
     while($WorkQueue->Count()) {      while($WorkQueue->Count()) {
  my $request = $Workqueue->dequeue(); # This is a transaction   my $request = $WorkQueue->dequeue(); # This is a transaction
  FailTransaction($request);   FailTransaction($request);
     }      }
 }  }
   
 =pod  =pod
   
   =head2 CloseAllLondConnections
   
   Close all connections open on lond prior to exit e.g.
   
   =cut
   sub CloseAllLondConnections {
       foreach my $Socket (keys %ActiveConnections) {
         if(exists($ActiveTransactions{$Socket})) {
    FailTransaction($ActiveTransactions{$Socket});
         }
         KillSocket($Socket);
       }
   }
   =cut
   
   =pod
   
 =head2 KillSocket  =head2 KillSocket
     
 Destroys a socket.  This function can be called either when a socket  Destroys a socket.  This function can be called either when a socket
Line 507  nonzero if we are allowed to create a ne Line 738  nonzero if we are allowed to create a ne
 sub KillSocket {  sub KillSocket {
     my $Socket = shift;      my $Socket = shift;
   
       Log("WARNING", "Shutting down a socket");
       $Socket->Shutdown();
   
     #  If the socket came from the active connection set,      #  If the socket came from the active connection set,
     #  delete its transaction... note that FailTransaction should      #  delete its transaction... note that FailTransaction should
     #  already have been called!!!      #  already have been called!!!
Line 518  sub KillSocket { Line 752  sub KillSocket {
     }      }
     if(exists($ActiveConnections{$Socket})) {      if(exists($ActiveConnections{$Socket})) {
  delete($ActiveConnections{$Socket});   delete($ActiveConnections{$Socket});
    $ConnectionCount--;
    if ($ConnectionCount < 0) { $ConnectionCount = 0; }
     }      }
     $ConnectionCount--;  
   
     #  If the connection count has gone to zero and there is work in the      #  If the connection count has gone to zero and there is work in the
     #  work queue, the work all gets failed with con_lost.      #  work queue, the work all gets failed with con_lost.
     #      #
     if($ConnectionCount == 0) {      if($ConnectionCount == 0) {
  EmptyQueue;   EmptyQueue();
    CloseAllLondConnections; # Should all already be closed but...
     }      }
 }  }
   
Line 551  The connection must echo the challenge b Line 786  The connection must echo the challenge b
 The challenge has been replied to.  The we are receiveing the   The challenge has been replied to.  The we are receiveing the 
 'ok' from the partner.  'ok' from the partner.
   
   =head3  State=ReadingVersionString
   
   We have requested the lond version and are reading the
   version back.  Upon completion, we'll store the version away
   for future use(?).
   
   =head3 State=HostSet
   
   We have selected the domain name of our peer (multhomed hosts)
   and are getting the reply (presumably ok) back.
   
 =head3 State=RequestingKey  =head3 State=RequestingKey
   
 The ok has been received and we need to send the request for  The ok has been received and we need to send the request for
Line 588  transaction is in progress, the socket a Line 834  transaction is in progress, the socket a
 =cut  =cut
   
 sub LondReadable {  sub LondReadable {
   
     my $Event      = shift;      my $Event      = shift;
     my $Watcher    = $Event->w;      my $Watcher    = $Event->w;
     my $Socket     = $Watcher->data;      my $Socket     = $Watcher->data;
     my $client     = undef;      my $client     = undef;
   
       &Debug(6,"LondReadable called state = ".$Socket->GetState());
   
   
     my $State = $Socket->GetState(); # All action depends on the state.      my $State = $Socket->GetState(); # All action depends on the state.
   
     &Debug(6,"LondReadable called state = ".$State);  
     SocketDump(6, $Socket);      SocketDump(6, $Socket);
       my $status = $Socket->Readable();
   
       &Debug(2, "Socket->Readable returned: $status");
   
     if($Socket->Readable() != 0) {      if($status != 0) {
  # bad return from socket read. Currently this means that   # bad return from socket read. Currently this means that
  # The socket has become disconnected. We fail the transaction.   # The socket has become disconnected. We fail the transaction.
   
    Log("WARNING",
       "Lond connection lost.");
  if(exists($ActiveTransactions{$Socket})) {   if(exists($ActiveTransactions{$Socket})) {
     Debug(3,"Lond connection lost failing transaction");  
     FailTransaction($ActiveTransactions{$Socket});      FailTransaction($ActiveTransactions{$Socket});
    } else {
       #  Socket is connecting and failed... need to mark
       #  no longer connecting.
      
       $LondConnecting = 0;
  }   }
  $Watcher->cancel();   $Watcher->cancel();
  KillSocket($Socket);   KillSocket($Socket);
    $ConnectionRetriesLeft--;       # Counts as connection failure
  return;   return;
     }      }
     SocketDump(6,$Socket);      SocketDump(6,$Socket);
Line 616  sub LondReadable { Line 874  sub LondReadable {
     $State = $Socket->GetState(); # Update in case of transition.      $State = $Socket->GetState(); # Update in case of transition.
     &Debug(6, "After read, state is ".$State);      &Debug(6, "After read, state is ".$State);
   
    if($State eq "Initialized") {      if($State eq "Initialized") {
   
   
     } elsif ($State eq "ChallengeReceived") {      } elsif ($State eq "ChallengeReceived") {
  #  The challenge must be echoed back;  The state machine   #  The challenge must be echoed back;  The state machine
  # in the connection takes care of setting that up.  Just   # in the connection takes care of setting that up.  Just
  # need to transition to writable:   # need to transition to writable:
   
  $Watcher->poll("w");  
  $Watcher->cb(\&LondWritable);   $Watcher->cb(\&LondWritable);
    $Watcher->poll("w");
   
     } elsif ($State eq "ChallengeReplied") {      } elsif ($State eq "ChallengeReplied") {
   
       } elsif ($State eq "RequestingVersion") {
    # Need to ask for the version... that is writiability:
   
    $Watcher->cb(\&LondWritable);
    $Watcher->poll("w");
   
       } elsif ($State eq "ReadingVersionString") {
    # Read the rest of the version string... 
       } elsif ($State eq "SetHost") {
    # Need to request the actual domain get set...
   
    $Watcher->cb(\&LondWritable);
    $Watcher->poll("w");
       } elsif ($State eq "HostSet") {
    # Reading the 'ok' from the peer.
   
     } elsif ($State eq "RequestingKey") {      } elsif ($State eq "RequestingKey") {
  #  The ok was received.  Now we need to request the key   #  The ok was received.  Now we need to request the key
  #  That requires us to be writable:   #  That requires us to be writable:
   
  $Watcher->poll("w");  
  $Watcher->cb(\&LondWritable);   $Watcher->cb(\&LondWritable);
    $Watcher->poll("w");
   
     } elsif ($State eq "ReceivingKey") {      } elsif ($State eq "ReceivingKey") {
   
     } elsif ($State eq "Idle") {      } elsif ($State eq "Idle") {
      
    # This is as good a spot as any to get the peer version
    # string:
      
    if($LondVersion eq "unknown") {
       $LondVersion = $Socket->PeerVersion();
       Log("INFO", "Connected to lond version: $LondVersion");
    }
  # If necessary, complete a transaction and then go into the   # If necessary, complete a transaction and then go into the
  # idle queue.   # idle queue.
    #  Note that a trasition to idle indicates a live lond
    # on the other end so reset the connection retries.
    #
    $ConnectionRetriesLeft = $ConnectionRetries; # success resets the count
    $Watcher->cancel();
  if(exists($ActiveTransactions{$Socket})) {   if(exists($ActiveTransactions{$Socket})) {
     Debug(8,"Completing transaction!!");      Debug(5,"Completing transaction!!");
     CompleteTransaction($Socket,       CompleteTransaction($Socket, 
  $ActiveTransactions{$Socket});   $ActiveTransactions{$Socket});
    } else {
       Log("SUCCESS", "Connection ".$ConnectionCount." to "
    .$RemoteHost." now ready for action");
  }   }
  $Watcher->cancel();  
  ServerToIdle($Socket); # Next work unit or idle.   ServerToIdle($Socket); # Next work unit or idle.
   
    #
    $LondConnecting = 0; # Best spot I can think of for this.
    # 
   
     } elsif ($State eq "SendingRequest") {      } elsif ($State eq "SendingRequest") {
  #  We need to be writable for this and probably don't belong   #  We need to be writable for this and probably don't belong
Line 662  sub LondReadable { Line 954  sub LondReadable {
   
   
     } else {      } else {
  # Invalid state.   # Invalid state.
  Debug(4, "Invalid state in LondReadable");   Debug(4, "Invalid state in LondReadable");
     }      }
 }  }
Line 731  is the socket on which to return a reply Line 1023  is the socket on which to return a reply
 sub LondWritable {  sub LondWritable {
     my $Event   = shift;      my $Event   = shift;
     my $Watcher = $Event->w;      my $Watcher = $Event->w;
     my @data    = $Watcher->data;      my $Socket  = $Watcher->data;
     Debug(6,"LondWritable State = ".$State." data has ".@data." elts.\n");      my $State   = $Socket->GetState();
   
     my $Socket  = $data; # I know there's at least a socket.      Debug(6,"LondWritable State = ".$State."\n");
   
    
     #  Figure out what to do depending on the state of the socket:      #  Figure out what to do depending on the state of the socket:
           
   
     my $State   = $Socket->GetState();  
   
   
     SocketDump(6,$Socket);      SocketDump(6,$Socket);
   
     if      ($State eq "Connected")         {      #  If the socket is writable, we must always write.
       # Only by writing will we undergo state transitions.
       # Old logic wrote in state specific code below, however
       # That forces us at least through another invocation of
       # this function after writability is possible again.
       # This logic also factors out common code for handling
       # write failures... in all cases, write failures 
       # Kill the socket.
       #  This logic makes the branches of the >big< if below
       # so that the writing states are actually NO-OPs.
   
       if ($Socket->Writable() != 0) {
    #  The write resulted in an error.
    # We'll treat this as if the socket got disconnected:
    Log("WARNING", "Connection to ".$RemoteHost.
       " has been disconnected");
    if(exists($ActiveTransactions{$Socket})) {
       FailTransaction($ActiveTransactions{$Socket});
    } else {
       #  In the process of conneting, so need to turn that off.
       
       $LondConnecting = 0;
    }
    $Watcher->cancel();
    KillSocket($Socket);
    return;
       }
   
  if ($Socket->Writable() != 0) {  
     #  The write resulted in an error.  
     # We'll treat this as if the socket got disconnected:  
   
     $Watcher->cancel();  
     KillSocket($Socket);  
     return;  
  }  
  #  "init" is being sent...  
   
       if      ($State eq "Connected")         {
   
    #  "init" is being sent...
    
     } elsif ($State eq "Initialized")       {      } elsif ($State eq "Initialized")       {
   
  # Now that init was sent, we switch    # Now that init was sent, we switch 
  # to watching for readability:   # to watching for readability:
   
  $Watcher->poll("r");  
  $Watcher->cb(\&LondReadable);   $Watcher->cb(\&LondReadable);
    $Watcher->poll("r");
   
     } elsif ($State eq "ChallengeReceived") {      } elsif ($State eq "ChallengeReceived") {
  # We received the challenge, now we    # We received the challenge, now we 
  # are echoing it back. This is a no-op,   # are echoing it back. This is a no-op,
  # we're waiting for the state to change   # we're waiting for the state to change
   
  if($Socket->Writable() != 0) {  
   
     $Watcher->cancel();  
     KillSocket($Socket);  
     return;  
  }  
   
     } elsif ($State eq "ChallengeReplied")  {      } elsif ($State eq "ChallengeReplied")  {
  # The echo was sent back, so we switch   # The echo was sent back, so we switch
  # to watching readability.   # to watching readability.
   
    $Watcher->cb(\&LondReadable);
    $Watcher->poll("r");
       } elsif ($State eq "RequestingVersion") {
    # Sending the peer a version request...
   
       } elsif ($State eq "ReadingVersionString") {
    # Transition to read since we have sent the
    # version command and now just need to read the
    # version string from the peer:
         
    $Watcher->cb(\&LondReadable);
  $Watcher->poll("r");   $Watcher->poll("r");
         
       } elsif ($State eq "SetHost") {
    #  Setting the remote domain...
   
       } elsif ($State eq "HostSet") {
    # Back to readable to get the ok.
         
  $Watcher->cb(\&LondReadable);   $Watcher->cb(\&LondReadable);
    $Watcher->poll("r");
         
   
     } elsif ($State eq "RequestingKey")     {      } elsif ($State eq "RequestingKey")     {
  # At this time we're requesting the key.   # At this time we're requesting the key.
  # again, this is essentially a no-op.   # again, this is essentially a no-op.
  # we'll write the next chunk until the  
  # state changes.  
   
  if($Socket->Writable() != 0) {  
     # Write resulted in an error.  
   
     $Watcher->cancel();  
     KillSocket($Socket);  
     return;  
   
  }  
     } elsif ($State eq "ReceivingKey")      {      } elsif ($State eq "ReceivingKey")      {
  # Now we need to wait for the key   # Now we need to wait for the key
  # to come back from the peer:   # to come back from the peer:
   
  $Watcher->poll("r");  
  $Watcher->cb(\&LondReadable);   $Watcher->cb(\&LondReadable);
    $Watcher->poll("r");
   
     } elsif ($State eq "SendingRequest")    {      } elsif ($State eq "SendingRequest")    {
    
  # At this time we are sending a request to the   # At this time we are sending a request to the
  # peer... write the next chunk:   # peer... write the next chunk:
   
  if($Socket->Writable() != 0) {  
   
     if(exists($ActiveTransactions{$Socket})) {  
  Debug(3, "Lond connection lost, failing transactions");  
  FailTransaction($ActiveTransactions{$Socket});  
     }  
     $Watcher->cancel();  
     KillSocket($Socket);  
     return;  
       
  }  
   
     } elsif ($State eq "ReceivingReply")    {      } elsif ($State eq "ReceivingReply")    {
  # The send has completed.  Wait for the   # The send has completed.  Wait for the
  # data to come in for a reply.   # data to come in for a reply.
  Debug(8,"Writable sent request/receiving reply");   Debug(8,"Writable sent request/receiving reply");
  $Watcher->poll("r");  
  $Watcher->cb(\&LondReadable);   $Watcher->cb(\&LondReadable);
    $Watcher->poll("r");
   
     } else {      } else {
  #  Control only passes here on an error:    #  Control only passes here on an error: 
Line 842  sub LondWritable { Line 1148  sub LondWritable {
           
 =cut  =cut
 sub QueueDelayed {  sub QueueDelayed {
       Debug(3,"QueueDelayed called");
   
     my $path = "$perlvar{'lonSockDir'}/delayed";      my $path = "$perlvar{'lonSockDir'}/delayed";
   
       Debug(4, "Delayed path: ".$path);
     opendir(DIRHANDLE, $path);      opendir(DIRHANDLE, $path);
     @alldelayed = grep /\.$RemoteHost$/, readdir DIRHANDLE;      
       my @alldelayed = grep /\.$RemoteHost$/, readdir DIRHANDLE;
     closedir(DIRHANDLE);      closedir(DIRHANDLE);
     my $dfname;      my $dfname;
     my $reqfile      my $reqfile;
     foreach $reqfile (sort @alldelayed) {      foreach $dfname (sort  @alldelayed) {
  $reqfile = $path/$reqfile;   $reqfile = "$path/$dfname";
    Debug(4, "queueing ".$reqfile);
  my $Handle = IO::File->new($reqfile);   my $Handle = IO::File->new($reqfile);
  my $cmd    = <$Handle>;   my $cmd    = <$Handle>;
  chomp($cmd);   chomp $cmd; # There may or may not be a newline...
    $cmd = $cmd."\n"; # now for sure there's exactly one newline.
  my $Transaction = LondTransaction->new($cmd);   my $Transaction = LondTransaction->new($cmd);
  $Transaction->SetDeferred($reqfile);   $Transaction->SetDeferred($reqfile);
  QueueTransaction($Transaction);   QueueTransaction($Transaction);
Line 879  sub MakeLondConnection { Line 1192  sub MakeLondConnection {
     my $Connection = LondConnection->new(&GetServerHost(),      my $Connection = LondConnection->new(&GetServerHost(),
  &GetServerPort());   &GetServerPort());
   
     if($Connection == undef) { # Needs to be more robust later.      if($Connection eq undef) { # Needs to be more robust later.
  Debug(0,"Failed to make a connection with lond.");   Log("CRITICAL","Failed to make a connection with lond.");
    $ConnectionRetriesLeft--;
    return 0; # Failure.
     }  else {      }  else {
   
  # The connection needs to have writability    # The connection needs to have writability 
  # monitored in order to send the init sequence   # monitored in order to send the init sequence
  # that starts the whole authentication/key   # that starts the whole authentication/key
  # exchange underway.   # exchange underway.
  #   #
  my $Socket = $Connection->GetSocket();   my $Socket = $Connection->GetSocket();
  if($Socket == undef) {   if($Socket eq undef) {
     die "did not get a socket from the connection";      &child_exit(-1, "did not get a socket from the connection");
  } else {   } else {
     &Debug(9,"MakeLondConnection got socket: ".$Socket);      &Debug(9,"MakeLondConnection got socket: ".$Socket);
  }   }
   
    $Connection->SetTimeoutCallback(\&SocketTimeout);
  $event = Event->io(fd       => $Socket,  
    my $event = Event->io(fd       => $Socket,
    poll     => 'w',     poll     => 'w',
    cb       => \&LondWritable,     cb       => \&LondWritable,
    data     => \$Connection,     data     => $Connection,
    desc => 'Connection to lond server');     desc => 'Connection to lond server');
  $ActiveConnections{$Connection} = $event;   $ActiveConnections{$Connection} = $event;
    if ($ConnectionCount == 0) {
       &SetupTimer; # Need to handle timeouts with connections...
    }
  $ConnectionCount++;   $ConnectionCount++;
    Debug(4, "Connection count = ".$ConnectionCount);
  if($ConnectionCount == 1) { # First Connection:   if($ConnectionCount == 1) { # First Connection:
     QueueDelayed;      QueueDelayed;
  }   }
    Log("SUCESS", "Created connection ".$ConnectionCount
       ." to host ".GetServerHost());
    $LondConnecting = 1; # Connection in progress.
    return 1; # Return success.
     }      }
           
 }  }
Line 936  The text of the request to send. Line 1260  The text of the request to send.
 =cut  =cut
   
 sub StartRequest {  sub StartRequest {
     my $Lond     = shift;  
     my $Request  = shift; # This is a LondTransaction.      my ($Lond, $Request) = @_;
           
     Debug(6, "StartRequest: ".$Request->getRequest());      Debug(6, "StartRequest: ".$Request->getRequest());
   
Line 947  sub StartRequest { Line 1271  sub StartRequest {
     $ActiveTransactions{$Lond} = $Request;      $ActiveTransactions{$Lond} = $Request;
   
     $Lond->InitiateTransaction($Request->getRequest());      $Lond->InitiateTransaction($Request->getRequest());
     $event = Event->io(fd      => $Lond->GetSocket(),      my $event = Event->io(fd      => $Socket,
        poll    => "w",         poll    => "w",
        cb      => \&LondWritable,         cb      => \&LondWritable,
        data    => $Lond,         data    => $Lond,
Line 986  sub QueueTransaction { Line 1310  sub QueueTransaction {
   
     my $LondSocket    = $IdleConnections->pop();      my $LondSocket    = $IdleConnections->pop();
     if(!defined $LondSocket) { # Need to queue request.      if(!defined $LondSocket) { # Need to queue request.
  Debug(8,"Must queue...");   Debug(5,"Must queue...");
  $WorkQueue->enqueue($requestData);   $WorkQueue->enqueue($requestData);
  if($ConnectionCount < $MaxConnectionCount) {   Debug(5, "Queue Transaction startnew $ConnectionCount $LondConnecting");
     Debug(4,"Starting additional lond connection");   if(($ConnectionCount < $MaxConnectionCount)   && (! $LondConnecting)) {
     MakeLondConnection();  
       if($ConnectionRetriesLeft > 0) {
    Debug(5,"Starting additional lond connection");
    if(&MakeLondConnection() == 0) {
       EmptyQueue(); # Fail transactions, can't make connection.
       CloseAllLondConnections; # Should all be closed but...
    }
       } else {
    ShowStatus(GetServerHost()." >>> DEAD !!!! <<<");
    $LondConnecting = 0;
    EmptyQueue(); # It's worse than that ... he's dead Jim.
    CloseAllLondConnections; # Should all be closed but..
       }
  }   }
     } else { # Can start the request:      } else { # Can start the request:
  Debug(8,"Can start...");   Debug(8,"Can start...");
Line 1003  sub QueueTransaction { Line 1339  sub QueueTransaction {
 =pod  =pod
   
 =head2 ClientRequest  =head2 ClientRequest
   
 Callback that is called when data can be read from the UNIX domain  Callback that is called when data can be read from the UNIX domain
 socket connecting us with an apache server process.  socket connecting us with an apache server process.
   
Line 1022  sub ClientRequest { Line 1357  sub ClientRequest {
     my $rv = $socket->recv($thisread, POSIX::BUFSIZ, 0);      my $rv = $socket->recv($thisread, POSIX::BUFSIZ, 0);
     Debug(8, "rcv:  data length = ".length($thisread)      Debug(8, "rcv:  data length = ".length($thisread)
   ." read =".$thisread);    ." read =".$thisread);
     unless (defined $rv && length($thisread)) {      unless (defined $rv  && length($thisread)) {
  # Likely eof on socket.   # Likely eof on socket.
  Debug(5,"Client Socket closed on lonc for ".$RemoteHost);   Debug(5,"Client Socket closed on lonc for ".$RemoteHost);
  close($socket);   close($socket);
  $watcher->cancel();   $watcher->cancel();
  delete($ActiveClients{$socket});   delete($ActiveClients{$socket});
    return;
     }      }
     Debug(8,"Data: ".$data." this read: ".$thisread);      Debug(8,"Data: ".$data." this read: ".$thisread);
     $data = $data.$thisread; # Append new data.      $data = $data.$thisread; # Append new data.
     $watcher->data($data);      $watcher->data($data);
     if($data =~ /(.*\n)/) { # Request entirely read.      if($data =~ /\n$/) { # Request entirely read.
    if($data eq "close_connection_exit\n") {
       Log("CRITICAL",
    "Request Close Connection ... exiting");
       CloseAllLondConnections();
       exit;
    }
  Debug(8, "Complete transaction received: ".$data);   Debug(8, "Complete transaction received: ".$data);
  my $Transaction = new LondTransaction->new($data);   if($LogTransactions) {
       Log("SUCCESS", "Transaction: '$data'"); # Transaction has \n.
    }
    my $Transaction = LondTransaction->new($data);
  $Transaction->SetClient($socket);   $Transaction->SetClient($socket);
  QueueTransaction($Transaction);   QueueTransaction($Transaction);
  $watcher->cancel(); # Done looking for input data.   $watcher->cancel(); # Done looking for input data.
Line 1042  sub ClientRequest { Line 1387  sub ClientRequest {
   
 }  }
   
   #
   #     Accept a connection request for a client (lonc child) and
   #    start up an event watcher to keep an eye on input from that 
   #    Event.  This can be called both from NewClient and from
   #    ChildProcess if we are started in DieWhenIdle mode.
   # Parameters:
   #    $socket       - The listener socket.
   # Returns:
   #   NONE
   # Side Effects:
   #    An event is made to watch the accepted connection.
   #    Active clients hash is updated to reflect the new connection.
   #    The client connection count is incremented.
   #
   sub accept_client {
       my ($socket) = @_;
   
       Debug(8, "Entering accept for lonc UNIX socket\n");
       my $connection = $socket->accept(); # Accept the client connection.
       Debug(8,"Connection request accepted from "
     .GetPeername($connection, AF_UNIX));
   
   
       my $description = sprintf("Connection to lonc client %d",
         $ClientConnection);
       Debug(9, "Creating event named: ".$description);
       Event->io(cb      => \&ClientRequest,
         poll    => 'r',
         desc    => $description,
         data    => "",
         fd      => $connection);
       $ActiveClients{$connection} = $ClientConnection;
       $ClientConnection++;
   }
   
 =pod  =pod
   
Line 1060  sub NewClient { Line 1439  sub NewClient {
     my $event      = shift; # Get the event parameters.      my $event      = shift; # Get the event parameters.
     my $watcher    = $event->w;       my $watcher    = $event->w; 
     my $socket     = $watcher->fd; # Get the event' socket.      my $socket     = $watcher->fd; # Get the event' socket.
     my $connection = $socket->accept(); # Accept the client connection.  
     Debug(8,"Connection request accepted from "  
   .GetPeername($connection, AF_UNIX));  
   
       &accept_client($socket);
     my $description = sprintf("Connection to lonc client %d",  
       $ClientConnection);  
     Debug(9, "Creating event named: ".$description);  
     Event->io(cb      => \&ClientRequest,  
       poll    => 'r',  
       desc    => $description,  
       data    => "",  
       fd      => $connection);  
     $ActiveClients{$connection} = $ClientConnection;  
     $ClientConnection++;  
 }  }
   
 =pod  =pod
Line 1084  sub NewClient { Line 1450  sub NewClient {
 Returns the name of the UNIX socket on which to listen for client  Returns the name of the UNIX socket on which to listen for client
 connections.  connections.
   
   =head2 Parameters:
   
       host (optional)  - Name of the host socket to return.. defaults to
                          the return from GetServerHost().
   
 =cut  =cut
   
 sub GetLoncSocketPath {  sub GetLoncSocketPath {
     return $UnixSocketDir."/".GetServerHost();  
       my $host = GetServerHost(); # Default host.
       if (@_) {
    ($host)  = @_; # Override if supplied.
       }
       return $UnixSocketDir."/".$host;
 }  }
   
 =pod  =pod
Line 1124  connection.  The event handler establish Line 1500  connection.  The event handler establish
 (creating a communcations channel), that int turn will establish  (creating a communcations channel), that int turn will establish
 another event handler to subess requests.  another event handler to subess requests.
   
   =head2  Parameters:
   
      host (optional)   Name of the host to set up a unix socket to.
   
 =cut  =cut
   
 sub SetupLoncListener {  sub SetupLoncListener {
   
       my $host       = GetServerHost(); # Default host.
       if (@_) {
    ($host)    = @_ # Override host with parameter.
       }
   
     my $socket;      my $socket;
     my $SocketName = GetLoncSocketPath();      my $SocketName = GetLoncSocketPath($host);
     unlink($SocketName);      unlink($SocketName);
     unless ($socket =IO::Socket::UNIX->new(Local  => $SocketName,      unless ($socket =IO::Socket::UNIX->new(Local  => $SocketName,
     Listen => 10,       Listen => 250, 
     Type   => SOCK_STREAM)) {      Type   => SOCK_STREAM)) {
  die "Failed to create a lonc listner socket";   if($I_am_child) {
       &child_exit(-1, "Failed to create a lonc listener socket");
    } else {
       die "Failed to create a lonc listner socket";
    }
     }      }
     Event->io(cb     => \&NewClient,      return $socket;
       poll   => 'r',  }
       desc   => 'Lonc listener Unix Socket',  
       fd     => $socket);  #
   #   Toggle transaction logging.
   #  Implicit inputs:  
   #     LogTransactions
   #  Implicit Outputs:
   #     LogTransactions
   sub ToggleTransactionLogging {
       print STDERR "Toggle transaction logging...\n";
       if(!$LogTransactions) {
    $LogTransactions = 1;
       } else {
    $LogTransactions = 0;
       }
   
   
       Log("SUCCESS", "Toggled transaction logging: $LogTransactions \n");
   }
   
   =pod 
   
   =head2 ChildStatus
    
   Child USR1 signal handler to report the most recent status
   into the status file.
   
   We also use this to reset the retries count in order to allow the
   client to retry connections with a previously dead server.
   =cut
   
   sub ChildStatus {
       my $event = shift;
       my $watcher = $event->w;
   
       Debug(2, "Reporting child status because : ".$watcher->data);
       my $docdir = $perlvar{'lonDocRoot'};
       my $fh = IO::File->new(">>$docdir/lon-status/loncstatus.txt");
       print $fh $$."\t".$RemoteHost."\t".$Status."\t".
    $RecentLogEntry."\n";
       #
       #  Write out information about each of the connections:
       #
       if ($DebugLevel > 2) {
    print $fh "Active connection statuses: \n";
    my $i = 1;
    print STDERR  "================================= Socket Status Dump:\n";
    foreach my $item (keys %ActiveConnections) {
       my $Socket = $ActiveConnections{$item}->data;
       my $state  = $Socket->GetState();
       print $fh "Connection $i State: $state\n";
       print STDERR "---------------------- Connection $i \n";
       $Socket->Dump(-1); # Ensure it gets dumped..
       $i++;
    }
       }
       $ConnectionRetriesLeft = $ConnectionRetries;
 }  }
   
 =pod  =pod
   
   =head2 SignalledToDeath
   
   Called in response to a signal that causes a chid process to die.
   
   =cut
   
   
   sub SignalledToDeath {
       my $event  = shift;
       my $watcher= $event->w;
   
       Debug(2,"Signalled to death! via ".$watcher->data);
       my ($signal) = $watcher->data;
       chomp($signal);
       Log("CRITICAL", "Abnormal exit.  Child $$ for $RemoteHost "
    ."died through "."\"$signal\"");
       LogPerm("F:lonc: $$ on $RemoteHost signalled to death: "
       ."\"$signal\"");
       exit 0;
   
   }
   
   =head2 ToggleDebug
   
   This sub toggles trace debugging on and off.
   
   =cut
   
   sub ToggleDebug {
       my $Current    = $DebugLevel;
          $DebugLevel = $NextDebugLevel;
          $NextDebugLevel = $Current;
   
       Log("SUCCESS", "New debugging level for $RemoteHost now $DebugLevel");
   
   }
   
 =head2 ChildProcess  =head2 ChildProcess
   
 This sub implements a child process for a single lonc daemon.  This sub implements a child process for a single lonc daemon.
   Optional parameter:
      $socket  - if provided, this is a socket already open for listen
                 on the client socket. Otherwise, a new listen is set up.
   
 =cut  =cut
   
 sub ChildProcess {  sub ChildProcess {
       #  If we are in DieWhenIdle mode, we've inherited all the
       #  events of our parent and those have to be cancelled or else
       #  all holy bloody chaos will result.. trust me, I already made
       #  >that< mistake.
   
       my $host = GetServerHost();
       foreach my $listener (keys %parent_dispatchers) {
    my $watcher = $parent_dispatchers{$listener};
    my $s       = $watcher->fd;
    if ($listener ne $host) { # Close everyone but me.
       Debug(5, "Closing listen socket for $listener");
       $s->close();
    }
    Debug(5, "Killing watcher for $listener");
   
     print "Loncnew\n";   $watcher->cancel();
    undef         $parent_dispatchers{$listener};
   
     # For now turn off signals.      }
           $I_am_child    = 1; # Seems like in spite of it all I may still getting
     $SIG{QUIT}  = IGNORE;                                  # parent event dispatches.. flag I'm a child.
     $SIG{HUP}   = IGNORE;  
     $SIG{USR1}  = IGNORE;  
     $SIG{INT}   = IGNORE;  
     $SIG{CHLD}  = IGNORE;  
     $SIG{__DIE__}  = IGNORE;  
   
     SetupTimer();  
           #
     SetupLoncListener();      #  Signals must be handled by the Event framework...
       #
   
       Event->signal(signal   => "QUIT",
     cb       => \&SignalledToDeath,
     data     => "QUIT");
       Event->signal(signal   => "HUP",
     cb       => \&ChildStatus,
     data     => "HUP");
       Event->signal(signal   => "USR1",
     cb       => \&ChildStatus,
     data     => "USR1");
       Event->signal(signal   => "USR2",
     cb       => \&ToggleTransactionLogging);
       Event->signal(signal   => "INT",
     cb       => \&ToggleDebug,
     data     => "INT");
   
       #  Figure out if we got passed a socket or need to open one to listen for
       #  client requests.
   
       my ($socket) = @_;
       if (!$socket) {
   
    $socket =  SetupLoncListener();
       }
       #  Establish an event to listen for client connection requests.
   
   
       Event->io(cb   => \&NewClient,
         poll => 'r',
         desc => 'Lonc Listener Unix Socket',
         fd   => $socket);
           
     $Event::Debuglevel = $DebugLevel;      $Event::Debuglevel = $DebugLevel;
           
Line 1173  sub ChildProcess { Line 1698  sub ChildProcess {
   
 # Setup the initial server connection:  # Setup the initial server connection:
           
     &MakeLondConnection();       # &MakeLondConnection(); // let first work request do it.
   
     if($ConnectionCount == 0) {      #  If We are in diwhenidle, need to accept the connection since the
  Debug(1,"Could not make initial connection..\n");      #  event may  not fire.
  Debug(1,"Will retry when there's work to do\n");  
       if ($DieWhenIdle) {
    &accept_client($socket);
     }      }
   
     Debug(9,"Entering event loop");      Debug(9,"Entering event loop");
     my $ret = Event::loop(); #  Start the main event loop.      my $ret = Event::loop(); #  Start the main event loop.
           
           
     die "Main event loop exited!!!";      &child_exit (-1,"Main event loop exited!!!");
 }  }
   
 #  Create a new child for host passed in:  #  Create a new child for host passed in:
   
 sub CreateChild {  sub CreateChild {
     my $host = shift;      my ($host, $socket) = @_;
   
       my $sigset = POSIX::SigSet->new(SIGINT);
       sigprocmask(SIG_BLOCK, $sigset);
     $RemoteHost = $host;      $RemoteHost = $host;
     Debug(3, "Forking off child for ".$RemoteHost);      Log("CRITICAL", "Forking server for ".$host);
     sleep(5);      my $pid          = fork;
     $pid          = fork;  
     if($pid) { # Parent      if($pid) { # Parent
  $ChildHash{$pid} = $RemoteHost;   $RemoteHost = "Parent";
    $ChildHash{$pid} = $host;
    $HostToPid{$host}= $pid;
    sigprocmask(SIG_UNBLOCK, $sigset);
   
     } else { # child.      } else { # child.
  ShowStatus("Connected to ".$RemoteHost);   ShowStatus("Connected to ".$RemoteHost);
  ChildProcess;   $SIG{INT} = 'DEFAULT';
    sigprocmask(SIG_UNBLOCK, $sigset);
    if(defined $socket) {
       &ChildProcess($socket);
    } else {
       ChildProcess; # Does not return.
    }
       }
   }
   
   # parent_client_connection:
   #    Event handler that processes client connections for the parent process.
   #    This sub is called when the parent is listening on a socket and
   #    a connection request arrives.  We must:
   #     Start a child process to accept the connection request.
   #     Kill our listen on the socket.
   # Parameter:
   #    event       - The event object that was created to monitor this socket.
   #                  event->w->fd is the socket.
   # Returns:
   #    NONE
   #
   sub parent_client_connection {
       if ($I_am_child) {
    #  Should not get here, but seem to anyway:
    &Debug(5," Child caught parent client connection event!!");
    my ($event) = @_;
    my $watcher = $event->w;
    $watcher->cancel(); # Try to kill it off again!!
       } else {
    &Debug(9, "parent_client_connection");
    my ($event)   = @_;
    my $watcher   = $event->w;
    my $socket    = $watcher->fd;
   
    # Lookup the host associated with this socket:
   
    my $host = $listening_to{$socket};
   
    # Start the child:
   
   
   
    &Debug(9,"Creating child for $host (parent_client_connection)");
    &CreateChild($host, $socket);
   
    # Clean up the listen since now the child takes over until it exits.
   
    $watcher->cancel(); # Nolonger listening to this event
    delete($listening_to{$socket});
    delete($parent_dispatchers{$host});
    $socket->close();
       }
   }
   
   # parent_listen:
   #    Opens a socket and starts a listen for the parent process on a client UNIX
   #    domain socket.
   #
   #    This involves:
   #       Creating a socket for listen.
   #       Removing any socket lock file
   #       Adding an event handler for this socket becoming readable
   #         To the parent's event dispatcher.
   # Parameters:
   #    loncapa_host    - LonCAPA cluster name of the host represented by the client
   #                      socket.
   # Returns:
   #    NONE
   #
   sub parent_listen {
       my ($loncapa_host) = @_;
       Debug(5, "parent_listen: $loncapa_host");
   
       my $socket    = &SetupLoncListener($loncapa_host);
       $listening_to{$socket} = $loncapa_host;
       if (!$socket) {
    die "Unable to create a listen socket for $loncapa_host";
       }
       
       my $lock_file = &GetLoncSocketPath($loncapa_host).".lock";
       unlink($lock_file); # No problem if it doesn't exist yet [startup e.g.]
   
       my $watcher = Event->io(cb    => \&parent_client_connection,
         poll  => 'r',
         desc  => "Parent listener unix socket ($loncapa_host)",
         fd    => $socket);
       $parent_dispatchers{$loncapa_host} = $watcher;
   
   }
   
   
   # listen_on_all_unix_sockets:
   #    This sub initiates a listen on all unix domain lonc client sockets.
   #    This will be called in the case where we are trimming idle processes.
   #    When idle processes are trimmed, loncnew starts up with no children,
   #    and only spawns off children when a connection request occurs on the
   #    client unix socket.  The spawned child continues to run until it has
   #    been idle a while at which point it eventually exits and once more
   #    the parent picks up the listen.
   #
   #  Parameters:
   #      NONE
   #  Implicit Inputs:
   #    The configuration file that has been read in by LondConnection.
   #  Returns:
   #     NONE
   #
   sub listen_on_all_unix_sockets {
       Debug(5, "listen_on_all_unix_sockets");
       my $host_iterator      =   &LondConnection::GetHostIterator();
       while (!$host_iterator->end()) {
    my $host_entry_ref =   $host_iterator->get();
    my $host_name      = $host_entry_ref->[0];
    Debug(9, "Listen for $host_name");
    &parent_listen($host_name);
    $host_iterator->next();
       }
   }
   
   #   server_died is called whenever a child process exits.
   #   Since this is dispatched via a signal, we must process all
   #   dead children until there are no more left.  The action
   #   is to:
   #      - Remove the child from the bookeeping hashes
   #      - Re-establish a listen on the unix domain socket associated
   #        with that host.
   # Parameters:
   #    The event, but we don't actually care about it.
   sub server_died {
       &Debug(9, "server_died called...");
       
       while(1) { # Loop until waitpid nowait fails.
    my $pid = waitpid(-1, WNOHANG);
    if($pid <= 0) {
       return; # Nothing left to wait for.
    }
    # need the host to restart:
   
    my $host = $ChildHash{$pid};
    if($host) { # It's for real...
       &Debug(9, "Caught sigchild for $host");
       delete($ChildHash{$pid});
       delete($HostToPid{$host});
       &parent_listen($host);
   
    } else {
       &Debug(5, "Caught sigchild for pid not in hosts hash: $pid");
    }
     }      }
   
 }  }
   
 #  #
 #  Parent process logic pass 1:  #  Parent process logic pass 1:
 #   For each entry in the hosts table, we will  #   For each entry in the hosts table, we will
Line 1220  sub CreateChild { Line 1903  sub CreateChild {
   
   
   
 ShowStatus("Parent writing pid file:");  
 $execdir = $perlvar{'lonDaemons'};  
 open (PIDSAVE, ">$execdir/logs/lonc.pid");  
 print PIDSAVE "$$\n";  
 close(PIDSAVE);  
   
 ShowStatus("Forming new session");  ShowStatus("Forming new session");
 my $childpid = fork;  my $childpid = fork;
Line 1232  if ($childpid != 0) { Line 1911  if ($childpid != 0) {
     sleep 4; # Give child a chacne to break to      sleep 4; # Give child a chacne to break to
     exit 0; # a new sesion.      exit 0; # a new sesion.
 }  }
   #
   #   Write my pid into the pid file so I can be located
   #
   
   ShowStatus("Parent writing pid file:");
   my $execdir = $perlvar{'lonDaemons'};
   open (PIDSAVE, ">$execdir/logs/lonc.pid");
   print PIDSAVE "$$\n";
   close(PIDSAVE);
   
   
   
 if (POSIX::setsid() < 0) {  if (POSIX::setsid() < 0) {
     print "Could not create new session\n";      print "Could not create new session\n";
Line 1240  if (POSIX::setsid() < 0) { Line 1930  if (POSIX::setsid() < 0) {
   
 ShowStatus("Forking node servers");  ShowStatus("Forking node servers");
   
   Log("CRITICAL", "--------------- Starting children ---------------");
   
   LondConnection::ReadConfig;               # Read standard config files.
 my $HostIterator = LondConnection::GetHostIterator;  my $HostIterator = LondConnection::GetHostIterator;
 while (! $HostIterator->end()) {  
   
     $hostentryref = $HostIterator->get();  if ($DieWhenIdle) {
     CreateChild($hostentryref->[0]);      $RemoteHost = "[parent]";
     $HostIterator->next();      &listen_on_all_unix_sockets();
   } else {
       
       while (! $HostIterator->end()) {
   
    my $hostentryref = $HostIterator->get();
    CreateChild($hostentryref->[0]);
    $HostHash{$hostentryref->[0]} = $hostentryref->[4];
    $HostIterator->next();
       }
 }  }
   
   $RemoteHost = "Parent Server";
   
 # Maintain the population:  # Maintain the population:
   
 ShowStatus("Parent keeping the flock");  ShowStatus("Parent keeping the flock");
   
 while(1) {  
     $deadchild = wait();  if ($DieWhenIdle) {
     if(exists $ChildHash{$deadchild}) { # need to restart.      # We need to setup a SIGChild event to handle the exit (natural or otherwise)
  $deadhost = $ChildHash{$deadchild};      # of the children.
  delete($ChildHash{$deadchild});  
  Debug(4,"Lost child pid= ".$deadchild.      Event->signal(cb       => \&server_died,
       "Connected to host ".$deadhost);     desc     => "Child exit handler",
  CreateChild($deadhost);     signal   => "CHLD");
   
   
       $Event::DebugLevel = $DebugLevel;
       Debug(9, "Parent entering event loop");
       my $ret = Event::loop();
       die "Main Event loop exited: $ret";
   
   
   } else {
       #
       #   Set up parent signals:
       #
       
       $SIG{INT}  = \&Terminate;
       $SIG{TERM} = \&Terminate; 
       $SIG{HUP}  = \&Restart;
       $SIG{USR1} = \&CheckKids; 
       $SIG{USR2} = \&UpdateKids; # LonManage update request.
       
       while(1) {
    my $deadchild = wait();
    if(exists $ChildHash{$deadchild}) { # need to restart.
       my $deadhost = $ChildHash{$deadchild};
       delete($HostToPid{$deadhost});
       delete($ChildHash{$deadchild});
       Log("WARNING","Lost child pid= ".$deadchild.
    "Connected to host ".$deadhost);
       Log("INFO", "Restarting child procesing ".$deadhost);
       CreateChild($deadhost);
    }
       }
   }
   
   
   =pod
   
   =head1 CheckKids
   
     Since kids do not die as easily in this implementation
   as the previous one, there  is no need to restart the
   dead ones (all dead kids get restarted when they die!!)
   The only thing this function does is to pass USR1 to the
   kids so that they report their status.
   
   =cut
   
   sub CheckKids {
       Debug(2, "Checking status of children");
       my $docdir = $perlvar{'lonDocRoot'};
       my $fh = IO::File->new(">$docdir/lon-status/loncstatus.txt");
       my $now=time;
       my $local=localtime($now);
       print $fh "LONC status $local - parent $$ \n\n";
       foreach my $pid (keys %ChildHash) {
    Debug(2, "Sending USR1 -> $pid");
    kill 'USR1' => $pid; # Tell Child to report status.
    sleep 1; # Wait so file doesn't intermix.
       }
   }
   
   =pod
   
   =head1  UpdateKids
   
   parent's SIGUSR2 handler.  This handler:
   
   =item
   
   Rereads the hosts file.
   
   =item
    
   Kills off (via sigint) children for hosts that have disappeared.
   
   =item
   
   QUITs  children for hosts that already exist (this just forces a status display
   and resets the connection retry count for that host.
   
   =item
   
   Starts new children for hosts that have been added to the hosts.tab file since
   the start of the master program and maintains them.
   
   =cut
   
   sub UpdateKids {
   
       Log("INFO", "Updating connections via SIGUSR2");
   
       #  Just in case we need to kill our own lonc, we wait a few seconds to
       #  give it a chance to receive and relay lond's response to the 
       #  re-init command.
       #
   
       sleep(2); # Wait a couple of seconds.
   
       my %hosts;                   # Indexed by loncapa hostname, value=ip.
       
       # Need to re-read  the host table:
       
       
       LondConnection::ReadConfig();
       my $I = LondConnection::GetHostIterator;
       while (! $I->end()) {
    my $item = $I->get();
    $hosts{$item->[0]} = $item->[4];
    $I->next();
     }      }
   
       #  The logic below is written for clarity not for efficiency.
       #  Since I anticipate that this function is only rarely called, that's
       #  appropriate.  There are certainly ways to combine the loops below,
       #  and anyone wishing to obscure the logic is welcome to go for it.
       #  Note that we don't re-direct sigchild.  Instead we do what's needed
       #  to the data structures that keep track of children to ensure that
       #  when sigchild is honored, no new child is born.
       #
   
       #  For each existing child; if it's host doesn't exist, kill the child.
   
       foreach my $child (keys %ChildHash) {
    my $oldhost = $ChildHash{$child};
    if (!(exists $hosts{$oldhost})) {
       Log("CRITICAL", "Killing child for $oldhost  host no longer exists");
       delete $ChildHash{$child};
       delete $HostToPid{$oldhost};
       kill 'QUIT' => $child;
    }
       }
       # For each remaining existing child; if it's host's ip has changed,
       # Restart the child on the new IP.
   
       foreach my $child (keys %ChildHash) {
    my $oldhost = $ChildHash{$child};
    my $oldip   = $HostHash{$oldhost};
    if ($hosts{$oldhost} ne $oldip) {
   
       # kill the old child.
   
       Log("CRITICAL", "Killing child for $oldhost host ip has changed...");
       delete $ChildHash{$child};
       delete $HostToPid{$oldhost};
       kill 'QUIT' => $child;
   
       # Do the book-keeping needed to start a new child on the
       # new ip.
   
       $HostHash{$oldhost} = $hosts{$oldhost};
       CreateChild($oldhost);
    }
       }
       # Finally, for each new host, not in the host hash, create a
       # enter the host and create a new child.
       # Force a status display of any existing process.
   
       foreach my $host (keys %hosts) {
    if(!(exists $HostHash{$host})) {
       Log("INFO", "New host $host discovered in hosts.tab...");
       $HostHash{$host} = $hosts{$host};
       CreateChild($host);
    } else {
       kill 'HUP' => $HostToPid{$host};    # status display.
    }
       }
   }
   
   
   =pod
   
   =head1 Restart
   
   Signal handler for HUP... all children are killed and
   we self restart.  This is an el-cheapo way to re read
   the config file.
   
   =cut
   
   sub Restart {
       &KillThemAll; # First kill all the children.
       Log("CRITICAL", "Restarting");
       my $execdir = $perlvar{'lonDaemons'};
       unlink("$execdir/logs/lonc.pid");
       exec("$execdir/loncnew");
 }  }
   
   =pod
   
   =head1 KillThemAll
   
   Signal handler that kills all children by sending them a 
   SIGHUP.  Responds to sigint and sigterm.
   
   =cut
   
   sub KillThemAll {
       Debug(2, "Kill them all!!");
       local($SIG{CHLD}) = 'IGNORE';      # Our children >will< die.
       foreach my $pid (keys %ChildHash) {
    my $serving = $ChildHash{$pid};
    ShowStatus("Nicely Killing lonc for $serving pid = $pid");
    Log("CRITICAL", "Nicely Killing lonc for $serving pid = $pid");
    kill 'QUIT' => $pid;
       }
   
   
   }
   
   
   #
   #  Kill all children via KILL.  Just in case the
   #  first shot didn't get them.
   
   sub really_kill_them_all_dammit
   {
       Debug(2, "Kill them all Dammit");
       local($SIG{CHLD} = 'IGNORE'); # In case some purist reenabled them.
       foreach my $pid (keys %ChildHash) {
    my $serving = $ChildHash{$pid};
    &ShowStatus("Nastily killing lonc for $serving pid = $pid");
    Log("CRITICAL", "Nastily killing lonc for $serving pid = $pid");
    kill 'KILL' => $pid;
    delete($ChildHash{$pid});
    my $execdir = $perlvar{'lonDaemons'};
    unlink("$execdir/logs/lonc.pid");
       }
   }
   =pod
   
   =head1 Terminate
    
   Terminate the system.
   
   =cut
   
   sub Terminate {
       &Log("CRITICAL", "Asked to kill children.. first be nice...");
       &KillThemAll;
       #
       #  By now they really should all be dead.. but just in case 
       #  send them all SIGKILL's after a bit of waiting:
   
       sleep(4);
       &Log("CRITICAL", "Now kill children nasty");
       &really_kill_them_all_dammit;
       Log("CRITICAL","Master process exiting");
       exit 0;
   
   }
   =pod
   
 =head1 Theory  =head1 Theory
   
 The event class is used to build this as a single process with an  The event class is used to build this as a single process with an

Removed from v.1.7  
changed lines
  Added in v.1.64


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