--- loncom/lonmaxima 2006/03/08 22:30:11 1.16
+++ loncom/lonmaxima 2008/02/14 14:09:43 1.37
@@ -3,7 +3,7 @@
# The LearningOnline Network with CAPA
# Connect to MAXIMA CAS
#
-# $Id: lonmaxima,v 1.16 2006/03/08 22:30:11 www Exp $
+# $Id: lonmaxima,v 1.37 2008/02/14 14:09:43 bisitz Exp $
#
# Copyright Michigan State University Board of Trustees
#
@@ -31,7 +31,6 @@
#
use Expect;
-use IPC::Open3;
use IO::Select;
use IO::Socket;
use IO::File;
@@ -44,7 +43,8 @@ use strict;
# global variables
my $PREFORK = 5; # number of children to maintain
-my $MAX_CLIENTS_PER_CHILD = 5; # number of clients each child should process
+my $MAX_CLIENTS_PER_CHILD = 50; # number of clients each child should process
+my $extra_children = 0;
my %children = (); # keys are current child process IDs
my $children = 0; # current number of children
my $status; # string for current status
@@ -52,6 +52,7 @@ my $pidfile; #
my $port; # path to UNIX socket file
my %perlvar; # configuration file info
my $lastlog; # last string that was logged
+
use vars qw($PREFORK $MAX_CLIENTS_PER_CHILD %children $children $status
$pidfile $port %perlvar $lastlog);
@@ -60,8 +61,13 @@ sub REAPER { # ta
# and MAXIMA processes
$SIG{CHLD} = \&REAPER;
my $pid = wait;
- $children--;
- delete($children{$pid});
+ if (exists($children{$pid})) {
+ $children--;
+ delete($children{$pid});
+ if ($extra_children) {
+ $extra_children--;
+ }
+ }
}
sub HUNTSMAN { # signal handler for SIGINT
@@ -126,6 +132,12 @@ sub catchexception {
}
+sub child_announce_death {
+ $SIG{USR1} = \&child_announce_death;
+ if ($extra_children < $PREFORK*10) {
+ $extra_children++;
+ }
+}
# ---------------------------------------------------------------- Main program
# -------------------------------- Set signal handlers to record abnormal exits
@@ -133,6 +145,7 @@ sub catchexception {
$SIG{'QUIT'}=\&catchexception;
$SIG{__DIE__}=\&catchexception;
+$SIG{USR1} = \&child_announce_death;
# ---------------------------------- Read loncapa_apache.conf and loncapa.conf
&status("Read loncapa.conf and loncapa_apache.conf");
@@ -212,7 +225,7 @@ for (1 .. $PREFORK) {
while (1) {
&status('Parent process, sleeping');
sleep; # wait for a signal (i.e., child's death)
- for (my $i = $children; $i < $PREFORK; $i++) {
+ for (my $i = $children; $i < $PREFORK+$extra_children; $i++) {
&status('Parent process, starting child');
&make_new_child($server); # top up the child pool
}
@@ -237,29 +250,58 @@ sub make_new_child {
return;
} else {
# Child can *not* return from this subroutine.
- $SIG{INT} = 'DEFAULT'; # make SIGINT kill us as it did before
+
+ my $ppid = getppid();
# unblock signals
sigprocmask(SIG_UNBLOCK, $sigset)
or die("Can't unblock SIGINT for fork: $!\n");
+ &logthis('New process started');
+
my $command=Expect->spawn('maxima');
- $command->log_stdout(0);
+ # soft/hard_close can take awhile and we really
+ # don't care we just want it gone
+ $SIG{INT} = sub {
+ my $pid = $command->pid();
+ kill('KILL'=>$pid);
+ exit;
+ };
- &getmaximaoutput($command);
+ $command->log_stdout(0);
+ #$command->log_file("$execdir/logs/lonmaxima.session.log");
for (my $i=0; $i < $MAX_CLIENTS_PER_CHILD; $i++) {
- &status('Accepting connections');
- my $client = $server->accept() or last;
- while (my $cmd=<$client>) {
- &status('Processing command');
- print $command &unescape($cmd).";\n";
- print $client &escape(&getmaximaoutput($command))."\n";
- }
+ &status('Accepting connections');
+ my $client = $server->accept() or last;
+ &sync($command);
+ print $command ("display2d:false;kill(all);\n");
+ &getmaximaoutput($command,2);
+ &sync($command);
+ my $syntaxerr = 0;
+ while (my $cmd=<$client>) {
+ &status('Processing command');
+ print $command &unescape($cmd);
+ my ($reply,$syntaxerr) = &getmaximaoutput($command,1);
+ print $client &escape($reply)."\n";
+ if ($syntaxerr) {
+ last;
+ } elsif ($reply=~/^Error\:/) {
+ &logthis('Died through '.$reply);
+ kill('USR1' => $ppid);
+ $client->close();
+ $command->hard_close();
+ exit;
+ }
+ &sync($command);
+ &status('Waiting for commands');
+ }
}
+ kill('USR1' => $ppid);
+ print $command ("quit();\n");
# tidy up gracefully and finish
-
+ sleep(15);
$command->soft_close();
# this exit is VERY important, otherwise the child will become
@@ -269,20 +311,73 @@ sub make_new_child {
}
}
+{
+ my $counter;
+ sub sync {
+ my ($command)=@_;
+ $counter++;
+ my $expect=$counter.time;
+ print $command "$expect;\n";
+ while (1) {
+ my $output=&getmaximaoutput($command,1);
+ if (($output=~/\Q$expect\E/) || ($output=~/^Error\:/)) {
+ return;
+ }
+ }
+ }
+}
+
sub getmaximaoutput {
- my ($command)=@_;
- my (undef,undef,undef,$output)=$command->expect(20, -re => '\(\%i\d+\)');
+ my ($command,$numcheck)=@_;
+ my $regexp = '\(\%i\d+\)';
+ my $syntaxerr=0;
+ if ($numcheck) {
+ if ($numcheck eq 2) {
+ # command was the killall so should get a full reset on
+ # command numbers
+ $regexp = '(\(\%i(1)\)|Incorrect syntax\:)';
+ } elsif ($command->match() =~ /\(\%i(\d+)\)/) {
+ my $nextmatch = $1+1;
+ $regexp = '(\(\%i'.$nextmatch.'\)|Incorrect syntax\:)';
+ }
+ }
+ my $timeout = 20;
+ my (undef,$error,$matched,$output) =
+ $command->expect($timeout, -re => $regexp);
+
+ if ($numcheck && $matched eq 'Incorrect syntax:') {
+ $syntaxerr = 1;
+ if (wantarray) {
+ return ($matched,$syntaxerr);
+ } else {
+ return $matched;
+ }
+ }
+ if ($error) {
+ return 'Error: '.$error;
+ }
+ $output =~ s/\r+//g; # Remove Windows-style linebreaks
my $foundoutput=0;
+ my $found_label=0;
my $realoutput='';
foreach my $line (split(/\n/,$output)) {
if ($line=~/\;/) { $foundoutput=1; next; }
if (!$foundoutput) { next; }
- my ($label)=($line=~s/^(\(\%o\d+\))//);
- if ($label) {
- $label=~s/\S/ /g;
- $line=$label.$line;
+ if ($line=~/^Incorrect syntax:/) { $syntaxerr = 1; next; }
+ if ($line=~ /^(\(\%o\d+\))(.+)$/){
+ my $label = $1;
+ $line = $2;
+ $label =~s/\S/ /g;
+ $line=$label.$line;
+ $found_label=1;
}
- $realoutput.=$line."\n";
+ if ($found_label) {
+ $realoutput.=$line."\n";
+ }
+ }
+ if (wantarray) {
+ return ($realoutput,$syntaxerr);
+ } else {
+ return $realoutput;
}
- return $realoutput;
}
500 Internal Server Error
Internal Server Error
The server encountered an internal error or
misconfiguration and was unable to complete
your request.
Please contact the server administrator at
root@localhost to inform them of the time this error occurred,
and the actions you performed just before this error.
More information about this error may be available
in the server error log.