--- loncom/lonmaxima	2006/03/03 23:31:06	1.4
+++ loncom/lonmaxima	2006/03/03 23:41:38	1.5
@@ -3,7 +3,7 @@
 # The LearningOnline Network with CAPA
 # Connect to MAXIMA CAS
 #
-# $Id: lonmaxima,v 1.4 2006/03/03 23:31:06 albertel Exp $
+# $Id: lonmaxima,v 1.5 2006/03/03 23:41:38 albertel Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -48,11 +48,13 @@ my $MAX_CLIENTS_PER_CHILD  = 5;        #
 my %children               = ();       # keys are current child process IDs
 my $children               = 0;        # current number of children
 my $status;                            # string for current status
+my $pidfile;                           # file containg parent process pid
+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
-	    $cmd_in $cmd_out $cmd_err $pidfile $port %perlvar $lastlog
-	    $currenthostid $client $server $cmd
-	    );
+	    $pidfile $port %perlvar $lastlog);
  
 sub maximareply {
     my ($cmd) = @_;
@@ -61,11 +63,13 @@ sub maximareply {
     my $exitstatus='';
 
     unless ($cmd=~/\;\n$/) { $cmd.=";\n"; }
+
+    my ($cmd_in, $cmd_out, $cmd_err);
     my $pid = open3($cmd_in, $cmd_out, $cmd_err, 'maxima');
     $children{$pid} = 1;
     
     print $cmd_in $cmd;
-    close $cmd_in;
+    close($cmd_in);
 
     &status("Command sent");
 
@@ -79,15 +83,15 @@ sub maximareply {
 	    } else {
 		my $line = scalar <$cmd_out>;
                 if ($line=~/^(\(\%o|\s)/) {
-                   $line=~s/^\(.*\)/     /; 
-                   $reply.=$line; 
-	       }
+		    $line=~s/^\(.*\)/     /; 
+		    $reply.=$line; 
+		}
 	    }
 	    $selector->remove($fh) if eof($fh);
 	}
     }
-    close $cmd_out;
-    close $cmd_err;
+    close($cmd_out);
+    close($cmd_err);
     &status("Command processed");
     return ($reply,$error,$exitstatus);
 }
@@ -156,12 +160,12 @@ sub catchexception {
     $SIG{QUIT}='DEFAULT';
     $SIG{__DIE__}='DEFAULT';
     chomp($signal);
-    &logthis("<font color=red>CRITICAL: "
-     ."ABNORMAL EXIT. Child $$ died through "
-     ."\"$signal\"</font>");
+    &logthis("<font color=\"red\">CRITICAL: "
+	     ."ABNORMAL EXIT. Child $$ died through "
+	     ."\"$signal\"</font>");
     die("Signal abend");
 }
- 
+
 
 
 # ---------------------------------------------------------------- Main program
@@ -178,11 +182,11 @@ $SIG{__DIE__}=\&catchexception;
 # ----------------------------- Make sure this process is running from user=www
 my $wwwid=getpwnam('www');
 if ($wwwid!=$<) {
-   my $emailto="$perlvar{'lonAdmEMail'},$perlvar{'lonSysEMail'}";
-   my $subj="LON: $currenthostid User ID mismatch";
-   system("echo 'User ID mismatch.  lonmaxima must be run as user www.' |\
+    my $emailto="$perlvar{'lonAdmEMail'},$perlvar{'lonSysEMail'}";
+    my $subj="LON: User ID mismatch";
+    system("echo 'User ID mismatch.  lonmaxima must be run as user www.' |\
  mailto $emailto -s '$subj' > /dev/null");
-   exit 1;
+    exit 1;
 }
  
 # --------------------------------------------- Check if other instance running
@@ -190,11 +194,12 @@ if ($wwwid!=$<) {
 $pidfile="$perlvar{'lonDaemons'}/logs/lonmaxima.pid";
  
 if (-e $pidfile) {
-   my $lfh=IO::File->new("$pidfile");
-   my $pide=<$lfh>;
-   chomp($pide);
-   if (kill 0 => $pide) { die "already running"; }
+    my $lfh=IO::File->new("$pidfile");
+    my $pide=<$lfh>;
+    chomp($pide);
+    if (kill 0 => $pide) { die "already running"; }
 }
+
 # ------------------------------------------------------- Listen to UNIX socket
 &status("Opening socket");
  
@@ -203,6 +208,7 @@ $port = "$perlvar{'lonSockDir'}/maximaso
 unlink($port);
  
 
+my $server;
 unless (
   $server = IO::Socket::UNIX->new(Local  => $port,
                                   Type   => SOCK_STREAM,
@@ -228,7 +234,7 @@ POSIX::setsid() or die "Can't start new
 # ------------------------------------------------------- Write our PID on disk
  
 my $execdir=$perlvar{'lonDaemons'};
-open (PIDSAVE,">$execdir/logs/lonmaxima.pid");
+open(PIDSAVE,">$execdir/logs/lonmaxima.pid");
 print PIDSAVE "$$\n";
 close(PIDSAVE);
 &logthis("<font color='red'>CRITICAL: ---------- Starting ----------</font>");
@@ -240,7 +246,7 @@ close(PIDSAVE);
      
 # Fork off our children.
 for (1 .. $PREFORK) {
-    &make_new_child();
+    &make_new_child($server);
 }
  
 # Install signal handlers.
@@ -253,11 +259,12 @@ while (1) {
     sleep;                          # wait for a signal (i.e., child's death)
     for (my $i = $children; $i < $PREFORK; $i++) {
         &status('Parent process, starting child');
-        &make_new_child();           # top up the child pool
+        &make_new_child($server);           # top up the child pool
     }
 }
                                                                                 
 sub make_new_child {
+    my ($server) = @_;
 
     # block signal for fork
     my $sigset = POSIX::SigSet->new(SIGINT);
@@ -281,7 +288,7 @@ sub make_new_child {
         sigprocmask(SIG_UNBLOCK, $sigset)
             or die "Can't unblock SIGINT for fork: $!\n";
 
-	&process_requests();
+	&process_requests($server);
 
         # tidy up gracefully and finish
 
@@ -293,11 +300,12 @@ sub make_new_child {
 }
 
 sub process_requests {
+    my ($server) = @_;
     # handle connections until we've reached $MAX_CLIENTS_PER_CHILD
     for (my $i=0; $i < $MAX_CLIENTS_PER_CHILD; $i++) {
 	&status('Accepting connections');     
-	$client = $server->accept( )     or last;
-	while ($cmd=<$client>) {
+	my $client = $server->accept()     or last;
+	while (my $cmd=<$client>) {
 	    &status('Processing command');
 	    print $client &escape((&maximareply(&unescape($cmd)))[0])."\n";
 	}