--- loncom/loncnew 2004/01/05 09:29:36 1.38 +++ loncom/loncnew 2004/09/29 10:37:35 1.61 @@ -2,7 +2,7 @@ # The LearningOnline Network with CAPA # lonc maintains the connections to remote computers # -# $Id: loncnew,v 1.38 2004/01/05 09:29:36 foxr Exp $ +# $Id: loncnew,v 1.61 2004/09/29 10:37:35 foxr Exp $ # # Copyright Michigan State University Board of Trustees # @@ -63,11 +63,6 @@ use LONCAPA::Configuration; use LONCAPA::HashIterator; -# -# Disable all signals we might receive from outside for now. -# - - # Read the httpd configuration file to get perl variables # normally set in apache modules: @@ -87,7 +82,9 @@ my $ClientConnection = 0; # Uniquifier f my $DebugLevel = 0; my $NextDebugLevel= 2; # So Sigint can toggle this. -my $IdleTimeout= 3600; # Wait an hour before pruning connections. +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. @@ -105,6 +102,14 @@ my $Status = ""; # Current stat 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. # # The hash below gives the HTML format for log messages @@ -112,13 +117,27 @@ my $ConnectionRetriesLeft=2; # Number of # my %LogFormats; -$LogFormats{"CRITICAL"} = "CRITICAL: %s"; -$LogFormats{"SUCCESS"} = "SUCCESS: %s"; -$LogFormats{"INFO"} = "INFO: %s"; -$LogFormats{"WARNING"} = "WARNING: %s"; +$LogFormats{"CRITICAL"} = "CRITICAL: %s"; +$LogFormats{"SUCCESS"} = "SUCCESS: %s"; +$LogFormats{"INFO"} = "INFO: %s"; +$LogFormats{"WARNING"} = "WARNING: %s"; $LogFormats{"DEFAULT"} = " %s "; +# UpdateStatus; +# Update the idle status display to show how many connections +# are left, retries and other stuff. +# +sub UpdateStatus { + if ($ConnectionRetriesLeft > 0) { + ShowStatus(GetServerHost()." Connection count: ".$ConnectionCount + ." Retries remaining: ".$ConnectionRetriesLeft + ." ($KeyMode)"); + } else { + ShowStatus(GetServerHost()." >> DEAD <<"); + } +} + =pod @@ -158,9 +177,9 @@ host and the time will be formatted into =cut sub Log { - my $severity = shift; - my $message = shift; - + + my ($severity, $message) = @_; + if(!$LogFormats{$severity}) { $severity = "DEFAULT"; } @@ -195,8 +214,10 @@ Returns the name of the host that a sock =cut sub GetPeername { - my $connection = shift; - my $AdrFamily = shift; + + + my ($connection, $AdrFamily) = @_; + my $peer = $connection->peername(); my $peerport; my $peerip; @@ -219,18 +240,20 @@ Invoked to issue a debug message. =cut sub Debug { - my $level = shift; - my $message = shift; + + my ($level, $message) = @_; + if ($level <= $DebugLevel) { Log("INFO", "-Debug- $message host = $RemoteHost"); } } sub SocketDump { - my $level = shift; - my $socket= shift; + + my ($level, $socket) = @_; + if($level <= $DebugLevel) { - $socket->Dump(); + $socket->Dump(-1); # Ensure it will get dumped. } } @@ -262,11 +285,19 @@ sub ShowStatus { sub SocketTimeout { my $Socket = shift; Log("WARNING", "A socket timeout was detected"); - Debug(0, " SocketTimeout called: "); - $Socket->Dump(); + 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()); + $LondConnecting = 0; + } + } #----------------------------- Timer management ------------------------ @@ -280,13 +311,12 @@ Invoked each timer tick. sub Tick { + my ($Event) = @_; + my $clock_watcher = $Event->w; + my $client; - if($ConnectionRetriesLeft > 0) { - ShowStatus(GetServerHost()." Connection count: ".$ConnectionCount - ." Retries remaining: ".$ConnectionRetriesLeft); - } else { - ShowStatus(GetServerHost()." >> DEAD <<"); - } + UpdateStatus(); + # Is it time to prune connection count: @@ -296,6 +326,22 @@ sub Tick { if($IdleSeconds > $IdleTimeout) { # Prune a connection... my $Socket = $IdleConnections->pop(); KillSocket($Socket); + $IdleSeconds = 0; # Otherwise all connections get trimmed to fast. + UpdateStatus(); + if(($ConnectionCount == 0) && $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); + } } } else { $IdleSeconds = 0; # Reset idle count if not idle. @@ -314,28 +360,32 @@ sub Tick { # 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. # - + # Note this code is dead now... + # my $Requests = $WorkQueue->Count(); - if (($ConnectionCount == 0) && ($Requests > 0)) { + if (($ConnectionCount == 0) && ($Requests > 0) && (!$LondConnecting)) { if ($ConnectionRetriesLeft > 0) { - my $Connections = ($Requests <= $MaxConnectionCount) ? - $Requests : $MaxConnectionCount; - Debug(5,"Work but no connections, start ".$Connections." of them"); - my $successCount = 0; - for (my $i =0; $i < $Connections; $i++) { - $successCount += MakeLondConnection(); - } - if($successCount == 0) { # All connections failed: + Debug(5,"Work but no connections, Make a new one"); + my $success; + $success = &MakeLondConnection; + if($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 @@ -376,6 +426,7 @@ long enough, it will be shut down and re sub ServerToIdle { my $Socket = shift; # Get the socket. + $KeyMode = $Socket->{AuthenticationMode}; delete($ActiveTransactions{$Socket}); # Server has no transaction &Debug(5, "Server to idle"); @@ -455,7 +506,7 @@ sub ClientWritable { } else { # Partial string sent. $Watcher->data(substr($Data, $result)); if($result == 0) { # client hung up on us!! - Log("INFO", "lonc pipe client hung up on us!"); + # Log("INFO", "lonc pipe client hung up on us!"); $Watcher->cancel; $Socket->shutdown(2); $Socket->close(); @@ -508,11 +559,14 @@ The transaction that is being completed. sub CompleteTransaction { &Debug(5,"Complete transaction"); - my $Socket = shift; - my $Transaction = shift; + + my ($Socket, $Transaction) = @_; if (!$Transaction->isDeferred()) { # Normal transaction my $data = $Socket->GetReply(); # Data to send. + if($LogTransactions) { + Log("SUCCESS", "Reply from lond: '$data'"); + } StartClientReply($Transaction, $data); } else { # Delete deferred transaction file. Log("SUCCESS", "A delayed transaction was completed"); @@ -520,7 +574,9 @@ sub CompleteTransaction { unlink $Transaction->getFile(); } } + =pod + =head1 StartClientReply Initiates a reply to a client where the reply data is a parameter. @@ -536,10 +592,10 @@ sub CompleteTransaction { The data to send to apached client. =cut + sub StartClientReply { - my $Transaction = shift; - my $data = shift; + my ($Transaction, $data) = @_; my $Client = $Transaction->getClient(); @@ -553,7 +609,9 @@ sub StartClientReply { cb => \&ClientWritable, data => $data); } + =pod + =head2 FailTransaction Finishes a transaction with failure because the associated lond socket @@ -563,8 +621,7 @@ sub StartClientReply { - The transaction is 'live' in which case we initiate the sending of "con_lost" to the client. -Deleting the transaction means killing it from the -%ActiveTransactions hash. +Deleting the transaction means killing it from the %ActiveTransactions hash. Parameters: @@ -572,20 +629,24 @@ Parameters: The LondTransaction we are failing. + =cut sub FailTransaction { my $transaction = shift; - Log("WARNING", "Failing transaction ".$transaction->getRequest()); + + # If the socket is dead, that's already logged. + + 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($transaction, "con_lost\n"); } - if($ConnectionRetriesLeft <= 0) { - Log("CRITICAL", "Host marked dead: ".GetServerHost()); - } } @@ -613,7 +674,10 @@ Close all connections open on lond prior =cut sub CloseAllLondConnections { foreach my $Socket (keys %ActiveConnections) { - KillSocket($Socket); + if(exists($ActiveTransactions{$Socket})) { + FailTransaction($ActiveTransactions{$Socket}); + } + KillSocket($Socket); } } =cut @@ -665,6 +729,7 @@ sub KillSocket { # if($ConnectionCount == 0) { EmptyQueue(); + CloseAllLondConnections; # Should all already be closed but... } } @@ -690,6 +755,17 @@ The connection must echo the challenge b The challenge has been replied to. The we are receiveing the '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 The ok has been received and we need to send the request for @@ -744,13 +820,18 @@ sub LondReadable { &Debug(2, "Socket->Readable returned: $status"); if($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. Log("WARNING", "Lond connection lost."); if(exists($ActiveTransactions{$Socket})) { FailTransaction($ActiveTransactions{$Socket}); + } else { + # Socket is connecting and failed... need to mark + # no longer connecting. + + $LondConnecting = 0; } $Watcher->cancel(); KillSocket($Socket); @@ -762,19 +843,34 @@ sub LondReadable { $State = $Socket->GetState(); # Update in case of transition. &Debug(6, "After read, state is ".$State); - if($State eq "Initialized") { + if($State eq "Initialized") { } elsif ($State eq "ChallengeReceived") { # The challenge must be echoed back; The state machine # in the connection takes care of setting that up. Just # need to transition to writable: - + $Watcher->cb(\&LondWritable); $Watcher->poll("w"); } elsif ($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 ($State eq "RequestingKey") { # The ok was received. Now we need to request the key @@ -786,6 +882,14 @@ sub LondReadable { } elsif ($State eq "ReceivingKey") { } 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: $LondVersion"); + } # If necessary, complete a transaction and then go into the # idle queue. # Note that a trasition to idle indicates a live lond @@ -802,6 +906,10 @@ sub LondReadable { .$RemoteHost." now ready for action"); } ServerToIdle($Socket); # Next work unit or idle. + + # + $LondConnecting = 0; # Best spot I can think of for this. + # } elsif ($State eq "SendingRequest") { # We need to be writable for this and probably don't belong @@ -815,7 +923,7 @@ sub LondReadable { } else { - # Invalid state. + # Invalid state. Debug(4, "Invalid state in LondReadable"); } } @@ -897,21 +1005,40 @@ sub LondWritable { SocketDump(6,$Socket); - if ($State eq "Connected") { - - 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 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}); - $Watcher->cancel(); - KillSocket($Socket); - return; + } else { + # In the process of conneting, so need to turn that off. + + $LondConnecting = 0; } - # "init" is being sent... + $Watcher->cancel(); + KillSocket($Socket); + return; + } - + + + if ($State eq "Connected") { + + # "init" is being sent... + } elsif ($State eq "Initialized") { # Now that init was sent, we switch @@ -919,40 +1046,43 @@ sub LondWritable { $Watcher->cb(\&LondReadable); $Watcher->poll("r"); - + } elsif ($State eq "ChallengeReceived") { # We received the challenge, now we # are echoing it back. This is a no-op, # we're waiting for the state to change - if($Socket->Writable() != 0) { - - $Watcher->cancel(); - KillSocket($Socket); - return; - } - } elsif ($State eq "ChallengeReplied") { # The echo was sent back, so we switch # 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); + $Watcher->poll("r"); + + } elsif ($State eq "SetHost") { + # Setting the remote domain... + + } elsif ($State eq "HostSet") { + # Back to readable to get the ok. + + $Watcher->cb(\&LondReadable); + $Watcher->poll("r"); + } elsif ($State eq "RequestingKey") { # At this time we're requesting the key. # 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") { # Now we need to wait for the key # to come back from the peer: @@ -961,20 +1091,10 @@ sub LondWritable { $Watcher->poll("r"); } elsif ($State eq "SendingRequest") { + # At this time we are sending a request to the # 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") { # The send has completed. Wait for the @@ -1067,7 +1187,9 @@ sub MakeLondConnection { data => $Connection, desc => 'Connection to lond server'); $ActiveConnections{$Connection} = $event; - + if ($ConnectionCount == 0) { + &SetupTimer; # Need to handle timeouts with connections... + } $ConnectionCount++; Debug(4, "Connection count = ".$ConnectionCount); if($ConnectionCount == 1) { # First Connection: @@ -1075,6 +1197,7 @@ sub MakeLondConnection { } Log("SUCESS", "Created connection ".$ConnectionCount ." to host ".GetServerHost()); + $LondConnecting = 1; # Connection in progress. return 1; # Return success. } @@ -1106,8 +1229,8 @@ The text of the request to send. =cut sub StartRequest { - my $Lond = shift; - my $Request = shift; # This is a LondTransaction. + + my ($Lond, $Request) = @_; Debug(6, "StartRequest: ".$Request->getRequest()); @@ -1158,15 +1281,20 @@ sub QueueTransaction { if(!defined $LondSocket) { # Need to queue request. Debug(5,"Must queue..."); $WorkQueue->enqueue($requestData); - if($ConnectionCount < $MaxConnectionCount) { + Debug(5, "Queue Transaction startnew $ConnectionCount $LondConnecting"); + if(($ConnectionCount < $MaxConnectionCount) && (! $LondConnecting)) { + if($ConnectionRetriesLeft > 0) { Debug(5,"Starting additional lond connection"); - if(MakeLondConnection() == 0) { + if(&MakeLondConnection() == 0) { EmptyQueue(); # Fail transactions, can't make connection. + CloseAllLondConnections; # Should all be closed but... } } else { ShowStatus(GetServerHost()." >>> DEAD !!!! <<<"); + $LondConnecting = 0; EmptyQueue(); # It's worse than that ... he's dead Jim. + CloseAllLondConnections; # Should all be closed but.. } } } else { # Can start the request: @@ -1209,7 +1337,7 @@ sub ClientRequest { Debug(8,"Data: ".$data." this read: ".$thisread); $data = $data.$thisread; # Append new 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"); @@ -1217,6 +1345,9 @@ sub ClientRequest { exit; } Debug(8, "Complete transaction received: ".$data); + if($LogTransactions) { + Log("SUCCESS", "Transaction: '$data'"); # Transaction has \n. + } my $Transaction = LondTransaction->new($data); $Transaction->SetClient($socket); QueueTransaction($Transaction); @@ -1267,10 +1398,20 @@ sub NewClient { Returns the name of the UNIX socket on which to listen for client connections. +=head2 Parameters: + + host (optional) - Name of the host socket to return.. defaults to + the return from GetServerHost(). + =cut sub GetLoncSocketPath { - return $UnixSocketDir."/".GetServerHost(); + + my $host = GetServerHost(); # Default host. + if (@_) { + ($host) = @_; # Override if supplied. + } + return $UnixSocketDir."/".$host; } =pod @@ -1307,22 +1448,46 @@ connection. The event handler establish (creating a communcations channel), that int turn will establish another event handler to subess requests. +=head2 Parameters: + + host (optional) Name of the host to set up a unix socket to. + =cut sub SetupLoncListener { + my $host = GetServerHost(); # Default host. + if (@_) { + ($host) = @_ # Override host with parameter. + } + my $socket; - my $SocketName = GetLoncSocketPath(); + my $SocketName = GetLoncSocketPath($host); unlink($SocketName); unless ($socket =IO::Socket::UNIX->new(Local => $SocketName, - Listen => 10, + Listen => 250, Type => SOCK_STREAM)) { die "Failed to create a lonc listner socket"; } - Event->io(cb => \&NewClient, - poll => 'r', - desc => 'Lonc listener Unix Socket', - fd => $socket); + return $socket; +} + +# +# Toggle transaction logging. +# Implicit inputs: +# LogTransactions +# Implicit Outputs: +# LogTransactions +sub ToggleTransactionLogging { + print STDERR "Toggle transaction logging...\n"; + if(!$LogTransactions) { + $LogTransactions = 1; + } else { + $LogTransactions = 0; + } + + + Log("SUCCESS", "Toggled transaction logging: $LogTransactions \n"); } =pod @@ -1335,6 +1500,7 @@ 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; @@ -1347,16 +1513,18 @@ sub ChildStatus { # # Write out information about each of the connections: # - 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(); - $i++; + if ($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; } @@ -1403,6 +1571,9 @@ sub ToggleDebug { =head2 ChildProcess This sub implements a child process for a single lonc daemon. +Optional parameter: + $socket - if provided, this is a socket already open for listen + on the client socket. Otherwise, a new listen is set up. =cut @@ -1411,7 +1582,7 @@ sub ChildProcess { # # Signals must be handled by the Event framework... -# + # Event->signal(signal => "QUIT", cb => \&SignalledToDeath, @@ -1422,13 +1593,22 @@ sub ChildProcess { Event->signal(signal => "USR1", cb => \&ChildStatus, data => "USR1"); + Event->signal(signal => "USR2", + cb => \&ToggleTransactionLogging); Event->signal(signal => "INT", cb => \&ToggleDebug, data => "INT"); - SetupTimer(); - SetupLoncListener(); + my ($socket) = @_; + if (!$socket) { + + $socket = SetupLoncListener(); + } + Event->io(cb => \&NewClient, + poll => 'r', + desc => 'Lonc Listener Unix Socket', + fd => $socket); $Event::Debuglevel = $DebugLevel; @@ -1436,7 +1616,7 @@ sub ChildProcess { # Setup the initial server connection: - # &MakeLondConnection(); // let first work requirest do it. + # &MakeLondConnection(); // let first work requirest do it. Debug(9,"Entering event loop"); @@ -1449,9 +1629,10 @@ sub ChildProcess { # Create a new child for host passed in: sub CreateChild { + my $host = shift; + my $sigset = POSIX::SigSet->new(SIGINT); sigprocmask(SIG_BLOCK, $sigset); - my $host = shift; $RemoteHost = $host; Log("CRITICAL", "Forking server for ".$host); my $pid = fork; @@ -1467,8 +1648,89 @@ sub CreateChild { sigprocmask(SIG_UNBLOCK, $sigset); ChildProcess; # Does not return. } +} +# parent_client_connection: +# Event handler that processes client connections for the parent process. +# This sub is called when the parent is listening on a socket and +# a connection request arrives. We must: +# Start a child process to accept the connection request. +# Kill our listen on the socket. +# Setup an event to handle the child process exit. (SIGCHLD). +# Parameter: +# event - The event object that was created to monitor this socket. +# event->w->fd is the socket. +# Returns: +# NONE +# +sub parent_client_connection { + die "DieWhenIdle processing not completely operational yet"; + +} + +# parent_listen: +# Opens a socket and starts a listen for the parent process on a client UNIX +# domain socket. +# +# This involves: +# Creating a socket for listen. +# Removing any socket lock file +# Adding an event handler for this socket becoming readable +# To the parent's event dispatcher. +# Parameters: +# loncapa_host - LonCAPA cluster name of the host represented by the client +# socket. +# Returns: +# NONE +# +sub parent_listen { + my ($loncapa_host) = @_; + Debug(5, "parent_listen: $loncapa_host"); + + my $socket = &SetupLoncListener($loncapa_host); + if (!$socket) { + die "Unable to create a listen socket for $loncapa_host"; + } + + my $lock_file = &GetLoncSocketPath().".lock"; + unlink($lock_file); # No problem if it doesn't exist yet [startup e.g.] + + Event->io(cb => &parent_client_connection, + poll => 'r', + desc => 'Parent listener unix socket', + fd => $socket); + +} + + +# 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(); + } } + # # Parent process logic pass 1: # For each entry in the hosts table, we will @@ -1518,44 +1780,61 @@ Log("CRITICAL", "--------------- Startin LondConnection::ReadConfig; # Read standard config files. my $HostIterator = LondConnection::GetHostIterator; -while (! $HostIterator->end()) { - my $hostentryref = $HostIterator->get(); - CreateChild($hostentryref->[0]); - $HostHash{$hostentryref->[0]} = $hostentryref->[4]; - $HostIterator->next(); +if ($DieWhenIdle) { + $RemoteHost = "[parent]"; + &listen_on_all_unix_sockets(); +} else { + + while (! $HostIterator->end()) { + + my $hostentryref = $HostIterator->get(); + CreateChild($hostentryref->[0]); + $HostHash{$hostentryref->[0]} = $hostentryref->[4]; + $HostIterator->next(); + } } + $RemoteHost = "Parent Server"; # Maintain the population: ShowStatus("Parent keeping the flock"); -# -# Set up parent signals: -# -$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); +if ($DieWhenIdle) { + $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 @@ -1722,17 +2001,33 @@ sub KillThemAll { local($SIG{CHLD}) = 'IGNORE'; # Our children >will< die. foreach my $pid (keys %ChildHash) { my $serving = $ChildHash{$pid}; - Debug(2, "Killing lonc for $serving pid = $pid"); - ShowStatus("Killing lonc for $serving pid = $pid"); - Log("CRITICAL", "Killing lonc for $serving pid = $pid"); + ShowStatus("Nicely Killing lonc for $serving pid = $pid"); + Log("CRITICAL", "Nicely Killing lonc for $serving pid = $pid"); kill 'QUIT' => $pid; - delete($ChildHash{$pid}); } - my $execdir = $perlvar{'lonDaemons'}; - unlink("$execdir/logs/lonc.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 @@ -1742,7 +2037,15 @@ Terminate the system. =cut sub Terminate { - KillThemAll; + &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;