--- loncom/loncnew 2006/07/19 19:56:26 1.75
+++ loncom/loncnew 2007/03/28 21:44:05 1.82
@@ -2,7 +2,7 @@
# The LearningOnline Network with CAPA
# lonc maintains the connections to remote computers
#
-# $Id: loncnew,v 1.75 2006/07/19 19:56:26 albertel Exp $
+# $Id: loncnew,v 1.82 2007/03/28 21:44:05 albertel Exp $
#
# Copyright Michigan State University Board of Trustees
#
@@ -60,7 +60,6 @@ use LONCAPA::Stack;
use LONCAPA::LondConnection;
use LONCAPA::LondTransaction;
use LONCAPA::Configuration;
-use LONCAPA::HashIterator;
use Fcntl qw(:flock);
@@ -74,8 +73,6 @@ my %perlvar = %{$perlvarref};
# parent and shared variables.
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.
@@ -96,6 +93,8 @@ my $executable = $0; # Get the full
# The variables below are only used by the child processes.
#
my $RemoteHost; # Name of host child is talking to.
+my $RemoteHostId; # default lonid of host child is talking to.
+my @all_host_ids;
my $UnixSocketDir= $perlvar{'lonSockDir'};
my $IdleConnections = Stack->new(); # Set of idle connections
my %ActiveConnections; # Connections to the remote lond.
@@ -114,7 +113,6 @@ my $LondConnecting = 0; # True wh
-my $DieWhenIdle = 1; # When true children die when trimmed -> 0.
my $I_am_child = 0; # True if this is the child process.
#
@@ -198,7 +196,7 @@ sub Log {
my $now = time;
my $local = localtime($now);
my $finalformat = "$local ($$) [$RemoteHost] [$Status] ";
- my $finalformat = $finalformat.$format."\n";
+ $finalformat = $finalformat.$format."\n";
# open the file and put the result.
@@ -308,12 +306,13 @@ sub SocketTimeout {
}
}
+
#
# 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.
+# exit. The child process 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
@@ -324,24 +323,20 @@ sub child_exit {
# 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:
+ #
+ # 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);
+ unlink(&GetLoncSocketPath());
- if($message) {
- die $message;
+ if ($message) {
+ die($message);
} else {
exit($exit_code);
}
@@ -375,7 +370,7 @@ sub Tick {
KillSocket($Socket);
$IdleSeconds = 0; # Otherwise all connections get trimmed to fast.
UpdateStatus();
- if(($ConnectionCount == 0) && $DieWhenIdle) {
+ if(($ConnectionCount == 0)) {
&child_exit(0);
}
@@ -1153,10 +1148,12 @@ sub LondWritable {
}
}
+
=pod
=cut
+
sub QueueDelayed {
Debug(3,"QueueDelayed called");
@@ -1165,16 +1162,7 @@ sub QueueDelayed {
Debug(4, "Delayed path: ".$path);
opendir(DIRHANDLE, $path);
- my @all_host_ids;
- my $host_iterator = &LondConnection::GetHostIterator();
- while (!$host_iterator->end()) {
- my ($host_id,$host_name) = @{$host_iterator->get()}[0,3];
- if ($host_name eq $RemoteHost) {
- push(@all_host_ids, $host_id);
- }
- $host_iterator->next();
- }
- my $host_id_re = '(?:'.join('|',@all_host_ids).')';
+ my $host_id_re = '(?:'.join('|',map {quotemeta($_)} (@all_host_ids)).')';
my @alldelayed = grep(/\.$host_id_re$/, readdir(DIRHANDLE));
closedir(DIRHANDLE);
foreach my $dfname (sort(@alldelayed)) {
@@ -1209,7 +1197,8 @@ sub MakeLondConnection {
.GetServerPort());
my $Connection = LondConnection->new(&GetServerHost(),
- &GetServerPort());
+ &GetServerPort(),
+ &GetHostId());
if($Connection eq undef) { # Needs to be more robust later.
Log("CRITICAL","Failed to make a connection with lond.");
@@ -1217,6 +1206,7 @@ sub MakeLondConnection {
return 0; # Failure.
} else {
+ $LondConnecting = 1; # Connection in progress.
# The connection needs to have writability
# monitored in order to send the init sequence
# that starts the whole authentication/key
@@ -1247,7 +1237,6 @@ sub MakeLondConnection {
}
Log("SUCESS", "Created connection ".$ConnectionCount
." to host ".GetServerHost());
- $LondConnecting = 1; # Connection in progress.
return 1; # Return success.
}
@@ -1410,7 +1399,7 @@ 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.
+# ChildProcess.
# Parameters:
# $socket - The listener socket.
# Returns:
@@ -1499,6 +1488,18 @@ sub GetServerHost {
=pod
+=head2 GetServerId
+
+Returns the hostid whose lond we talk with.
+
+=cut
+
+sub GetHostId {
+ return $RemoteHostId; # Setup by the fork.
+}
+
+=pod
+
=head2 GetServerPort
Returns the lond port number.
@@ -1526,15 +1527,14 @@ another event handler to subess requests
=cut
sub SetupLoncListener {
+ my ($host,$SocketName) = @_;
+ if (!$host) { $host = &GetServerHost(); }
+ if (!$SocketName) { $SocketName = &GetLoncSocketPath($host); }
- my $host = GetServerHost(); # Default host.
- if (@_) {
- ($host) = @_ # Override host with parameter.
- }
- my $socket;
- my $SocketName = GetLoncSocketPath($host);
unlink($SocketName);
+
+ my $socket;
unless ($socket =IO::Socket::UNIX->new(Local => $SocketName,
Listen => 250,
Type => SOCK_STREAM)) {
@@ -1663,7 +1663,7 @@ Optional parameter:
=cut
sub ChildProcess {
- # If we are in DieWhenIdle mode, we've inherited all the
+ # 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.
@@ -1731,7 +1731,7 @@ sub ChildProcess {
desc => 'Lonc Listener Unix Socket',
fd => $socket);
- $Event::Debuglevel = $DebugLevel;
+ $Event::DebugLevel = $DebugLevel;
Debug(9, "Making initial lond connection for ".$RemoteHost);
@@ -1739,12 +1739,9 @@ sub ChildProcess {
# &MakeLondConnection(); // let first work request do it.
- # If We are in diwhenidle, need to accept the connection since the
- # event may not fire.
+ # need to accept the connection since the event may not fire.
- if ($DieWhenIdle) {
- &accept_client($socket);
- }
+ &accept_client($socket);
Debug(9,"Entering event loop");
my $ret = Event::loop(); # Start the main event loop.
@@ -1756,7 +1753,7 @@ sub ChildProcess {
# Create a new child for host passed in:
sub CreateChild {
- my ($host, $socket) = @_;
+ my ($host, $hostid) = @_;
my $sigset = POSIX::SigSet->new(SIGINT);
sigprocmask(SIG_BLOCK, $sigset);
@@ -1766,18 +1763,14 @@ sub CreateChild {
if($pid) { # Parent
$RemoteHost = "Parent";
$ChildHash{$pid} = $host;
- $HostToPid{$host}= $pid;
sigprocmask(SIG_UNBLOCK, $sigset);
-
+ undef(@all_host_ids);
} else { # child.
+ $RemoteHostId = $hostid;
ShowStatus("Connected to ".$RemoteHost);
$SIG{INT} = 'DEFAULT';
sigprocmask(SIG_UNBLOCK, $sigset);
- if(defined $socket) {
- &ChildProcess($socket);
- } else {
- ChildProcess; # Does not return.
- }
+ &ChildProcess(); # Does not return.
}
}
@@ -1805,27 +1798,48 @@ sub 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();
+ my $connection = $socket->accept(); # Accept the client connection.
+ Event->io(cb => \&get_remote_hostname,
+ poll => 'r',
+ data => "",
+ fd => $connection);
}
}
+sub get_remote_hostname {
+ my ($event) = @_;
+ my $watcher = $event->w;
+ my $socket = $watcher->fd;
+
+ my $thisread;
+ my $rv = $socket->recv($thisread, POSIX::BUFSIZ, 0);
+ Debug(8, "rcv: data length = ".length($thisread)." read =".$thisread);
+ if (!defined($rv) || length($thisread) == 0) {
+ # Likely eof on socket.
+ Debug(5,"Client Socket closed on lonc for p_c_c");
+ close($socket);
+ $watcher->cancel();
+ return;
+ }
+
+ my $data = $watcher->data().$thisread;
+ $watcher->data($data);
+ if($data =~ /\n$/) { # Request entirely read.
+ chomp($data);
+ } else {
+ return;
+ }
+
+ &Debug(5,"Creating child for $data (parent_client_connection)");
+ (my $hostname,my $lonid,@all_host_ids) = split(':',$data);
+ &CreateChild($hostname,$lonid);
+
+ # Clean up the listen since now the child takes over until it exits.
+ $watcher->cancel(); # Nolonger listening to this event
+ $socket->send("done\n");
+ $socket->close();
+}
+
# parent_listen:
# Opens a socket and starts a listen for the parent process on a client UNIX
# domain socket.
@@ -1845,23 +1859,43 @@ sub parent_listen {
my ($loncapa_host) = @_;
Debug(5, "parent_listen: $loncapa_host");
- my $socket = &SetupLoncListener($loncapa_host);
+ my ($socket,$file);
+ if (!$loncapa_host) {
+ $loncapa_host = 'common_parent';
+ $file = $perlvar{'lonSockCreate'};
+ } else {
+ $file = &GetLoncSocketPath($loncapa_host);
+ }
+ $socket = &SetupLoncListener($loncapa_host,$file);
+
$listening_to{$socket} = $loncapa_host;
if (!$socket) {
die "Unable to create a listen socket for $loncapa_host";
}
- my $lock_file = &GetLoncSocketPath($loncapa_host).".lock";
+ my $lock_file = $file.".lock";
unlink($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);
+ my $watcher =
+ Event->io(cb => \&parent_client_connection,
+ poll => 'r',
+ desc => "Parent listener unix socket ($loncapa_host)",
+ data => "",
+ fd => $socket);
$parent_dispatchers{$loncapa_host} = $watcher;
}
+sub parent_clean_up {
+ my ($loncapa_host) = @_;
+ Debug(5, "parent_clean_up: $loncapa_host");
+
+ my $socket_file = &GetLoncSocketPath($loncapa_host);
+ unlink($socket_file); # No problem if it doesn't exist yet [startup e.g.]
+ my $lock_file = $socket_file.".lock";
+ unlink($lock_file); # No problem if it doesn't exist yet [startup e.g.]
+}
+
# listen_on_all_unix_sockets:
# This sub initiates a listen on all unix domain lonc client sockets.
@@ -1891,6 +1925,11 @@ sub listen_on_all_unix_sockets {
}
}
+sub listen_on_common_socket {
+ Debug(5, "listen_on_common_socket");
+ &parent_listen();
+}
+
# 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
@@ -1914,8 +1953,7 @@ sub server_died {
if($host) { # It's for real...
&Debug(9, "Caught sigchild for $host");
delete($ChildHash{$pid});
- delete($HostToPid{$host});
- &parent_listen($host);
+ &parent_clean_up($host);
} else {
&Debug(5, "Caught sigchild for pid not in hosts hash: $pid");
@@ -1972,21 +2010,9 @@ ShowStatus("Forking node servers");
Log("CRITICAL", "--------------- Starting children ---------------");
LondConnection::ReadConfig; # Read standard config files.
-my $HostIterator = LondConnection::GetHostIterator;
-if ($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]";
+&listen_on_common_socket();
$RemoteHost = "Parent Server";
@@ -1995,68 +2021,38 @@ $RemoteHost = "Parent Server";
ShowStatus("Parent keeping the flock");
-if ($DieWhenIdle) {
- # We need to setup a SIGChild event to handle the exit (natural or otherwise)
- # of the children.
-
- Event->signal(cb => \&server_died,
- desc => "Child exit handler",
- signal => "CHLD");
-
-
- # Set up all the other signals we set up. We'll vector them off to the
- # same subs as we would for DieWhenIdle false and, if necessary, conditionalize
- # the code there.
-
- $parent_handlers{INT} = Event->signal(cb => \&Terminate,
- desc => "Parent INT handler",
- signal => "INT");
- $parent_handlers{TERM} = Event->signal(cb => \&Terminate,
- desc => "Parent TERM handler",
- signal => "TERM");
- $parent_handlers{HUP} = Event->signal(cb => \&Restart,
- desc => "Parent HUP handler.",
- signal => "HUP");
- $parent_handlers{USR1} = Event->signal(cb => \&CheckKids,
- desc => "Parent USR1 handler",
- signal => "USR1");
- $parent_handlers{USR2} = Event->signal(cb => \&UpdateKids,
- desc => "Parent USR2 handler.",
- signal => "USR2");
-
- # Start procdesing events.
-
- $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);
- }
- }
-}
+# We need to setup a SIGChild event to handle the exit (natural or otherwise)
+# of the children.
+Event->signal(cb => \&server_died,
+ desc => "Child exit handler",
+ signal => "CHLD");
+
+
+# Set up all the other signals we set up.
+
+$parent_handlers{INT} = Event->signal(cb => \&Terminate,
+ desc => "Parent INT handler",
+ signal => "INT");
+$parent_handlers{TERM} = Event->signal(cb => \&Terminate,
+ desc => "Parent TERM handler",
+ signal => "TERM");
+$parent_handlers{HUP} = Event->signal(cb => \&KillThemAll,
+ desc => "Parent HUP handler.",
+ signal => "HUP");
+$parent_handlers{USR1} = Event->signal(cb => \&CheckKids,
+ desc => "Parent USR1 handler",
+ signal => "USR1");
+$parent_handlers{USR2} = Event->signal(cb => \&UpdateKids,
+ desc => "Parent USR2 handler.",
+ signal => "USR2");
+
+# Start procdesing events.
+
+$Event::DebugLevel = $DebugLevel;
+Debug(9, "Parent entering event loop");
+my $ret = Event::loop();
+die "Main Event loop exited: $ret";
=pod
@@ -2124,8 +2120,7 @@ sub UpdateKids {
# The down side is transactions that are in flight will get timed out
# (lost unless they are critical).
- &Restart();
-
+ &KillThemAll();
}
@@ -2165,8 +2160,6 @@ sub KillThemAll {
Log("CRITICAL", "Nicely Killing lonc for $serving pid = $pid");
kill 'QUIT' => $pid;
}
-
-
}
@@ -2211,6 +2204,14 @@ sub Terminate {
exit 0;
}
+
+sub my_hostname {
+ use Sys::Hostname;
+ my $name = &hostname();
+ &Debug(9,"Name is $name");
+ return $name;
+}
+
=pod
=head1 Theory