[BACK]Return to loncnew CVS log [TXT] [DIR] Up to [LON-CAPA] / loncom

Diff for /loncom/loncnew between versions 1.87 and 1.99

version 1.87, 2007/06/18 22:49:52 version 1.99, 2011/06/17 16:36:29
Line 26 Line 26
 # http://www.lon-capa.org/  # http://www.lon-capa.org/
 #  #
 #  #
 # new lonc handles n request out bver m connections to londs.  # new lonc handles n request out over 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 85  my $ClientConnection = 0; # Uniquifier f Line 85  my $ClientConnection = 0; # Uniquifier f
   
 my $DebugLevel = 0;  my $DebugLevel = 0;
 my $NextDebugLevel= 2; # So Sigint can toggle this.  my $NextDebugLevel= 2; # So Sigint can toggle this.
 my $IdleTimeout= 600; # Wait 10 minutes before pruning connections.  my $IdleTimeout= 5*60; # Seconds to wait prior to pruning connections.
   
 my $LogTransactions = 0; # When True, all transactions/replies get logged.  my $LogTransactions = 0; # When True, all transactions/replies get logged.
 my $executable      = $0; # Get the full path to me.  my $executable      = $0; # Get the full path to me.
Line 349  sub child_exit { Line 349  sub child_exit {
   
 =head2 Tick  =head2 Tick
   
 Invoked  each timer tick.  Invoked each timer tick.
   
 =cut  =cut
   
Line 441  Trigger disconnections of idle sockets. Line 441  Trigger disconnections of idle sockets.
   
 sub SetupTimer {  sub SetupTimer {
     Debug(6, "SetupTimer");      Debug(6, "SetupTimer");
     Event->timer(interval => 1, cb => \&Tick );      Event->timer(interval => 1, cb => \&Tick,
    hard => 1);
 }  }
   
 =pod  =pod
Line 487  sub ServerToIdle { Line 488  sub ServerToIdle {
   
 Event callback for when a client socket is writable.  Event callback for when a client socket is writable.
   
 This callback is established when a transaction reponse is  This callback is established when a transaction response is
 avaiable from lond.  The response is forwarded to the unix socket  available from lond.  The response is forwarded to the unix socket
 as it becomes writable in this sub.  as it becomes writable in this sub.
   
 Parameters:  Parameters:
Line 558  sub ClientWritable { Line 559  sub ClientWritable {
     if($errno == POSIX::EWOULDBLOCK   ||      if($errno == POSIX::EWOULDBLOCK   ||
        $errno == POSIX::EAGAIN        ||         $errno == POSIX::EAGAIN        ||
        $errno == POSIX::EINTR) {         $errno == POSIX::EINTR) {
  # No action taken?   # No action taken...the socket will be writable firing the event again
    # which will result in a retry of the write.
     } else { # Unanticipated errno.      } else { # Unanticipated errno.
  &Debug(5,"ClientWritable error or peer shutdown".$RemoteHost);   &Debug(5,"ClientWritable error or peer shutdown".$RemoteHost);
  $Watcher->cancel; # Stop the watcher.   $Watcher->cancel; # Stop the watcher.
Line 587  Parameters: Line 589  Parameters:
   
 =item Socket  =item Socket
   
 Socket on which the lond transaction occured.  This is a  Socket on which the lond transaction occurred.  This is a
 LondConnection. The data received is in the TransactionReply member.  LondConnection. The data received are in the TransactionReply member.
   
 =item Transaction  =item Transaction
   
Line 628  sub CompleteTransaction { Line 630  sub CompleteTransaction {
   
 =item data  =item data
   
     The data to send to apached client.      The data to send to apache client.
   
 =cut  =cut
   
Line 741  Parameters: Line 743  Parameters:
   
 =item Restart  =item Restart
   
 nonzero if we are allowed to create a new connection.  non-zero if we are allowed to create a new connection.
   
 =cut  =cut
   
Line 761  sub KillSocket { Line 763  sub KillSocket {
  delete ($ActiveTransactions{$Socket});   delete ($ActiveTransactions{$Socket});
     }      }
     if(exists($ActiveConnections{$Socket})) {      if(exists($ActiveConnections{$Socket})) {
    $ActiveConnections{$Socket}->cancel;
  delete($ActiveConnections{$Socket});   delete($ActiveConnections{$Socket});
  $ConnectionCount--;   $ConnectionCount--;
  if ($ConnectionCount < 0) { $ConnectionCount = 0; }   if ($ConnectionCount < 0) { $ConnectionCount = 0; }
Line 769  sub KillSocket { Line 772  sub KillSocket {
     #  work queue, the work all gets failed with con_lost.      #  work queue, the work all gets failed with con_lost.
     #      #
     if($ConnectionCount == 0) {      if($ConnectionCount == 0) {
    $LondConnecting = 0; # No connections so also not connecting.
  EmptyQueue();   EmptyQueue();
  CloseAllLondConnections; # Should all already be closed but...   CloseAllLondConnections; # Should all already be closed but...
     }      }
       UpdateStatus();
 }  }
   
 =pod  =pod
Line 783  is readable.  The action is state depend Line 788  is readable.  The action is state depend
   
 =head3 State=Initialized  =head3 State=Initialized
   
 We''re waiting for the challenge, this is a no-op until the  We're waiting for the challenge, this is a no-op until the
 state changes.  state changes.
   
 =head3 State=Challenged   =head3 State=Challenged 
Line 793  The connection must echo the challenge b Line 798  The connection must echo the challenge b
   
 =head3 State=ChallengeReplied  =head3 State=ChallengeReplied
   
 The challenge has been replied to.  The we are receiveing the   The challenge has been replied to.  Then we are receiving the 
 'ok' from the partner.  'ok' from the partner.
   
 =head3  State=ReadingVersionString  =head3  State=ReadingVersionString
Line 819  The the key has been requested, now we a Line 824  The the key has been requested, now we a
 =head3 State=Idle   =head3 State=Idle 
   
 The encryption key has been negotiated or we have finished   The encryption key has been negotiated or we have finished 
 reading data from the a transaction.   If the callback data has  reading data from the a transaction.   If the callback data have
 a client as well as the socket iformation, then we are   a client as well as the socket information, then we are 
 doing a transaction and the data received is relayed to the client  doing a transaction and the data received are relayed to the client
 before the socket is put on the idle list.  before the socket is put on the idle list.
   
 =head3 State=SendingRequest  =head3 State=SendingRequest
Line 838  to readable to receive the reply. Line 843  to readable to receive the reply.
 The parameter to this function are:  The parameter to this function are:
   
 The event. Implicit in this is the watcher and its data.  The data   The event. Implicit in this is the watcher and its data.  The data 
 contains at least the lond connection object and, if a   contain at least the lond connection object and, if a 
 transaction is in progress, the socket attached to the local client.  transaction is in progress, the socket attached to the local client.
   
 =cut  =cut
Line 943  sub LondReadable { Line 948  sub LondReadable {
     CompleteTransaction($Socket,       CompleteTransaction($Socket, 
  $ActiveTransactions{$Socket});   $ActiveTransactions{$Socket});
  } else {   } else {
     Log("SUCCESS", "Connection ".$ConnectionCount." to "      my $count = $Socket->GetClientData();
       Log("SUCCESS", "Connection ".$count." to "
  .$RemoteHost." now ready for action");   .$RemoteHost." now ready for action");
  }   }
  ServerToIdle($Socket); # Next work unit or idle.   ServerToIdle($Socket); # Next work unit or idle.
Line 980  event.  The action taken is very state d Line 986  event.  The action taken is very state d
 =head3 State = Connected   =head3 State = Connected 
   
 The connection is in the process of sending the 'init' hailing to the  The connection is in the process of sending the 'init' hailing to the
 lond on the remote end.  The connection object''s Writable member is  lond on the remote end.  The connection object's Writable member is
 called.  On error, ConnectionError is called to destroy the connection  called.  On error, ConnectionError is called to destroy the connection
 and remove it from the ActiveConnections hash  and remove it from the ActiveConnections hash
   
Line 1191  sub QueueDelayed { Line 1197  sub QueueDelayed {
 =head2 MakeLondConnection  =head2 MakeLondConnection
   
 Create a new lond connection object, and start it towards its initial  Create a new lond connection object, and start it towards its initial
 idleness.  Once idle, it becomes elligible to receive transactions  idleness.  Once idle, it becomes eligible to receive transactions
 from the work queue.  If the work queue is not empty when the  from the work queue.  If the work queue is not empty when the
 connection is completed and becomes idle, it will dequeue an entry and  connection is completed and becomes idle, it will dequeue an entry and
 start off on it.  start off on it.
Line 1206  sub MakeLondConnection { Line 1212  sub MakeLondConnection {
  &GetServerPort(),   &GetServerPort(),
  &GetHostId());   &GetHostId());
   
     if($Connection eq undef) { # Needs to be more robust later.      if($Connection eq undef) {
  Log("CRITICAL","Failed to make a connection with lond.");   Log("CRITICAL","Failed to make a connection with lond.");
  $ConnectionRetriesLeft--;   $ConnectionRetriesLeft--;
  return 0; # Failure.   return 0; # Failure.
Line 1237  sub MakeLondConnection { Line 1243  sub MakeLondConnection {
     &SetupTimer; # Need to handle timeouts with connections...      &SetupTimer; # Need to handle timeouts with connections...
  }   }
  $ConnectionCount++;   $ConnectionCount++;
    $Connection->SetClientData($ConnectionCount);
  Debug(4, "Connection count = ".$ConnectionCount);   Debug(4, "Connection count = ".$ConnectionCount);
  if($ConnectionCount == 1) { # First Connection:   if($ConnectionCount == 1) { # First Connection:
     QueueDelayed;      QueueDelayed;
  }   }
  Log("SUCESS", "Created connection ".$ConnectionCount   Log("SUCCESS", "Created connection ".$ConnectionCount
     ." to host ".GetServerHost());      ." to host ".GetServerHost());
  return 1; # Return success.   return 1; # Return success.
     }      }
Line 1262  reply. Line 1269  reply.
   
 =item $Client  =item $Client
   
 Connection to the client that is making this request We got the  Connection to the client that is making this request. We got the
 request from this socket, and when the request has been relayed to  request from this socket, and when the request has been relayed to
 lond and we get a reply back from lond it will get sent to this  lond and we get a reply back from lond it will get sent to this
 socket.  socket.
Line 1348  sub QueueTransaction { Line 1355  sub QueueTransaction {
     }      }
 }  }
   
 #-------------------------- Lonc UNIX socket handling ---------------------  #-------------------------- Lonc UNIX socket handling -------------------
   
 =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 1452  sub accept_client { Line 1459  sub accept_client {
 Callback that is called when a connection is received on the unix  Callback that is called when a connection is received on the unix
 socket for a new client of lonc.  The callback is parameterized by the  socket for a new client of lonc.  The callback is parameterized by the
 event.. which is a-priori assumed to be an io event, and therefore has  event.. which is a-priori assumed to be an io event, and therefore has
 an fd member that is the Listener socket.  We Accept the connection  an fd member that is the Listener socket.  We accept the connection
 and register a new event on the readability of that socket:  and register a new event on the readability of that socket:
   
 =cut  =cut
Line 1532  sub GetServerPort { Line 1539  sub GetServerPort {
 Setup a lonc listener event.  The event is called when the socket  Setup a lonc listener event.  The event is called when the socket
 becomes readable.. that corresponds to the receipt of a new  becomes readable.. that corresponds to the receipt of a new
 connection.  The event handler established will accept the connection  connection.  The event handler established will accept the connection
 (creating a communcations channel), that int turn will establish  (creating a communications channel), that in turn will establish
 another event handler to subess requests.  another event handler to subess requests.
   
 =head2  Parameters:  =head2  Parameters:
Line 1672  sub ToggleDebug { Line 1679  sub ToggleDebug {
   
 This sub implements a child process for a single lonc daemon.  This sub implements a child process for a single lonc daemon.
 Optional parameter:  Optional parameter:
    $socket  - if provided, this is a socket already open for listen     $socket  - if provided, this is a socket already open for listening
               on the client socket. Otherwise, a new listen is set up.                on the client socket. Otherwise, a new listener is set up.
   
 =cut  =cut
   
Line 1730  sub ChildProcess { Line 1737  sub ChildProcess {
   cb       => \&ToggleDebug,    cb       => \&ToggleDebug,
   data     => "INT");    data     => "INT");
   
       # Block the pipe signal we'll get when the socket disconnects.  We detect 
       # socket disconnection via send/receive failures. On disconnect, the
       # socket becomes readable .. which will force the disconnect detection.
   
       my $set = POSIX::SigSet->new(SIGPIPE);
       sigprocmask(SIG_BLOCK, $set);
   
     #  Figure out if we got passed a socket or need to open one to listen for      #  Figure out if we got passed a socket or need to open one to listen for
     #  client requests.      #  client requests.
   
Line 1773  sub CreateChild { Line 1787  sub CreateChild {
     my $sigset = POSIX::SigSet->new(SIGINT);      my $sigset = POSIX::SigSet->new(SIGINT);
     sigprocmask(SIG_BLOCK, $sigset);      sigprocmask(SIG_BLOCK, $sigset);
     $RemoteHost = $host;      $RemoteHost = $host;
       ShowStatus('Parent keeping the flock'); # Update time in status message.
     Log("CRITICAL", "Forking server for ".$host);      Log("CRITICAL", "Forking server for ".$host);
     my $pid          = fork;      my $pid          = fork;
     if($pid) { # Parent      if($pid) { # Parent
Line 2065  die "Main Event loop exited: $ret"; Line 2080  die "Main Event loop exited: $ret";
 =head1 CheckKids  =head1 CheckKids
   
   Since kids do not die as easily in this implementation    Since kids do not die as easily in this implementation
 as the previous one, there  is no need to restart the  as the previous one, there is no need to restart the
 dead ones (all dead kids get restarted when they die!!)  dead ones (all dead kids get restarted when they die!!)
 The only thing this function does is to pass USR1 to the  The only thing this function does is to pass USR1 to the
 kids so that they report their status.  kids so that they report their status.
Line 2135  sub UpdateKids { Line 2150  sub UpdateKids {
 =head1 Restart  =head1 Restart
   
 Signal handler for HUP... all children are killed and  Signal handler for HUP... all children are killed and
 we self restart.  This is an el-cheapo way to re read  we self restart.  This is an el-cheapo way to re-read
 the config file.  the config file.
   
 =cut  =cut
Line 2265  A hash of lond connections that have no Line 2280  A hash of lond connections that have no
 can be closed if they are idle for a long enough time.  can be closed if they are idle for a long enough time.
   
 =cut  =cut
   
   =pod
   
   =head1 Log messages
   
   The following is a list of log messages that can appear in the 
   lonc.log file.  Each log file has a severity and a message.
   
   =over 2
   
   =item Warning  A socket timeout was detected
   
   If there are pending transactions in the socket's queue,
   they are failed (saved if critical).  If the connection
   retry count gets exceeded by this, the
   remote host is marked as dead.
   Called when timeouts occurred during the connection and
   connection dialog with a remote host.
   
   =item Critical Host makred DEAD <hostname>   
   
   The numer of retry counts for contacting a host was
   exceeded. The host is marked dead an no 
   further attempts will be made by that child.
   
   =item Info lonc pipe client hung up on us     
   
   Write to the client pipe indicated no data transferred
   Socket to remote host is shut down.  Reply to the client 
   is discarded.  Note: This is commented out in &ClientWriteable
   
   =item Success  Reply from lond: <data>   
   
   Can be enabled for debugging by setting LogTransactions to nonzero.
   Indicates a successful transaction with lond, <data> is the data received
   from the remote lond.
   
   =item Success A delayed transaction was completed  
   
   A transaction that must be reliable was executed and completed
   as lonc restarted.  This is followed by a mesage of the form
   
     S: client-name : request
   
   =item WARNING  Failing transaction <cmd>:<subcmd>  
   
   Transaction failed on a socket, but the failure retry count for the remote
   node has not yet been exhausted (the node is not yet marked dead).
   cmd is the command, subcmd is the subcommand.  This results from a con_lost
   when communicating with lond.
   
   =item WARNING Shutting down a socket     
   
   Called when a socket is being closed to lond.  This is emitted both when 
   idle pruning is being done and when the socket has been disconnected by the remote.
   
   =item WARNING Lond connection lost.
   
   Called when a read from lond's socket failed indicating lond has closed the 
   connection or died.  This should be followed by one or more
   
    "WARNING Failing transaction..." msgs for each in-flight or queued transaction.
   
   =item INFO Connected to lond version:  <version> 
   
   When connection negotiation is complete, the lond version is requested and logged here.
   
   =item SUCCESS Connection n to host now ready for action
   
   Emitted when connection has been completed with lond. n is then number of 
   concurrent connections and host, the host to which the connection has just
   been established.
   
   =item WARNING Connection to host has been disconnected
   
   Write to a lond resulted in failure status.  Connection to lond is dropped.
   
   =item SUCCESS Created connection n to host host 
   
   Initial connection request to host..(before negotiation).
   
   =item CRITICAL Request Close Connection ... exiting
   
   Client has sent "close_connection_exit"   The loncnew server is exiting.
   
   =item INFO Resetting Connection Retries 
   
   Client has sent "reset_retries" The lond connection retries are reset to zero for the
   corresponding lond.
   
   =item SUCCESS Transaction <data>
   
   Only emitted if the global variable $LogTransactions was set to true.
   A client has requested a lond transaction <data> is the contents of the request.
   
   =item SUCCESS Toggled transaction logging <LogTransactions>
                                       
   The state of the $LogTransactions global has been toggled, and its current value
   (after being toggled) is displayed.  When non zero additional logging of transactions
   is enabled for debugging purposes.  Transaction logging is toggled on receipt of a USR2
   signal.
   
   =item CRITICAL Abnormal exit. Child <pid> for <host> died thorugh signal.
   
   QUIT signal received.  lonc child process is exiting.
   
   =item SUCCESS New debugging level for <RemoteHost> now <DebugLevel>
                                       
   Debugging toggled for the host loncnew is talking with.
   Currently debugging is a level based scheme with higher number 
   conveying more information.  The daemon starts out at
   DebugLevel 0 and can toggle back and forth between that and
   DebugLevel 2  These are controlled by
   the global variables $DebugLevel and $NextDebugLevel
   The debug level can go up to 9.
   SIGINT toggles the debug level.  The higher the debug level the 
   more debugging information is spewed.  See the Debug
   sub in loncnew.
   
   =item CRITICAL Forking server for host  
   
   A child is being created to service requests for the specified host.
   
   
   =item WARNING Request for a second child on hostname
                                       
   Somehow loncnew was asked to start a second child on a host that already had a child
   servicing it.  This request is not honored, but themessage is emitted.  This could happen
   due to a race condition.  When a client attempts to contact loncnew for a new host, a child
   is forked off to handle the requests for that server.  The parent then backs off the Unix
   domain socket leaving it for the child to service all requests.  If in the time between
   creating the child, and backing off, a new connection request comes in to the unix domain
   socket, this could trigger (unlikely but remotely possible),.
   
   =item CRITICAL ------ Starting Children ----
   
   This message should probably be changed to "Entering event loop"  as the loncnew only starts
   children as needed.  This message is emitted as new events are established and
   the event processing loop is entered.
   
   =item INFO Updating connections via SIGUSR2
                                       
   SIGUSR2 received. The original code would kill all clients, re-read the host file,
   then restart children for each host.  Now that children are started on demand, this
   just kills all child processes and lets requests start them as needed again.
   
   
   =item CRITICAL Restarting
   
   SigHUP received.  all the children are killed and the script exec's itself to start again.
   
   =item CRITICAL Nicely killing lonc for host pid = <pid>
   
   Attempting to kill the child that is serving the specified host (pid given) cleanly via
   SIGQUIT.  The child should handle that, clean up nicely and exit.
   
   =item CRITICAL Nastily killing lonc for host pid = <pid>
   
   The child specified did not die when requested via SIGQUIT.  Therefore it is killed
   via SIGKILL.
   
   =item CRITICAL Asked to kill children.. first be nice..
   
   In the parent's INT handler.  INT kills the child processes.  This inidicate loncnew
   is about to attempt to kill all known children via SIGQUIT.  This message should be followed 
   by one "Nicely killing" message for each extant child.
   
   =item CRITICAL Now kill children nasty 
   
   In the parent's INT handler. remaining children are about to be killed via
   SIGKILL. Should be followed by a Nastily killing... for each lonc child that 
   refused to die.
   
   =item CRITICAL Master process exiting
   
   In the parent's INT handler. just prior to the exit 0 call.
   
   =back
   
   =cut
Removed from v.1.87  
changed lines
  Added in v.1.99

FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>