--- loncom/interface/printout.pl	2007/10/11 22:49:49	1.128
+++ loncom/interface/printout.pl	2008/03/11 01:48:57	1.132
@@ -1,7 +1,7 @@
 #!/usr/bin/perl
 # CGI-script to run LaTeX, dvips, ps2ps, ps2pdf etc.
 #
-# $Id: printout.pl,v 1.128 2007/10/11 22:49:49 albertel Exp $
+# $Id: printout.pl,v 1.132 2008/03/11 01:48:57 www Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -43,6 +43,7 @@ use LONCAPA::Configuration;
 
 use strict;
 
+my $busy_wait_timeout = 30; 
 
 #   Determine if a user is operating as a student for this course/domain.
 #Parameters:
@@ -205,7 +206,7 @@ $env{'request.noversionuri'} = '/cgi-bin
       close $temporary_file;  
       my $noteps;
       my %prog_state;
-      if ($advanced_role) { %prog_state=&Apache::lonhtmlcommon::Create_PrgWin('','Coverting Images to EPS','Picture Conversion Status',$#content_of_file,'inline','80');  }
+      if ($advanced_role) { %prog_state=&Apache::lonhtmlcommon::Create_PrgWin('','Converting Images to EPS','Picture Conversion Status',$#content_of_file,'inline','80');  }
       print('<br />');
       foreach my $not_eps (@content_of_file) {
 	  chomp($not_eps);
@@ -376,17 +377,17 @@ foreach $texfile (@texfile) {
       my $name_file = $2;
       my $path_file = $1.'/';
       chdir $path_file;
-      my $dvi_file= $name_file; $dvi_file =~ s/\.tex/$name_range\.dvi/;
+      my $dvi_file= $name_file; $dvi_file =~ s/\.tex$/\.dvi/;
       &busy_wait_command("latex $name_file 1>/dev/null 2>/dev/null",
 			 "for $status_statement now LaTeXing file",
-			 \%prog_state,$dvi_file);
+			 \%prog_state,$dvi_file, $busy_wait_timeout);
       if ($tableofcontents eq 'yes') {
       &busy_wait_command("latex $name_file 1>/dev/null 2>/dev/null",
 			 "for $status_statement First LaTeX of file for table of contents",
-			 \%prog_state,$dvi_file);
+			 \%prog_state,$dvi_file, $busy_wait_timeout);
       &busy_wait_command("latex $name_file 1>/dev/null 2>/dev/null",
 			 "for $status_statement Second LaTeX of file for table of contents",
-			 \%prog_state,$dvi_file);
+			 \%prog_state,$dvi_file,$busy_wait_timeout);
       } #to create table of contents
       my $idxname=$name_file;
       $idxname=~s/\.tex$/\.idx/;
@@ -396,7 +397,7 @@ foreach $texfile (@texfile) {
 			     \%prog_state,$idxname);
 	  &busy_wait_command("latex $name_file 1>/dev/null 2>/dev/null",
 			     "for $status_statement now LaTeXing file for index section",
-			     \%prog_state,$dvi_file);
+			     \%prog_state,$dvi_file, $busy_wait_timeout);
       } #to create index
       #Do we have a latex error in the log file?
       my $logfilename = $texfile; $logfilename =~ s/\.tex$/\.log/;
@@ -448,7 +449,7 @@ foreach $texfile (@texfile) {
               $logfilename=~s{^\Q$perlvar{'lonPrtDir'}\E}{/prtspool};
 	      print "<a href=\"$logfilename\">Your log file </a></big></b>";
 	      print "\n";
-              #link tooriginal LaTeX file (included according Michael Hamlin desire)
+              #link to original LaTeX file
 	      my $tex_temporary_file=IO::File->new($texfile) || die "Couldn't open tex file $texfile for reading: $!\n";
 	      my @tex_content_of_file = <$tex_temporary_file>;
 	      close $tex_temporary_file; 
@@ -512,14 +513,14 @@ foreach $texfile (@texfile) {
 	      #
 	      &busy_wait_command("latex $latex_file 1>/dev/null 2>/dev/null",
 				 "for $status_statement first latex to repaginate",
-				 \%prog_state, $name_file);
+				 \%prog_state, $name_file,$busy_wait_timeout);
 	      if ($tableofcontents eq 'yes') {
 		  &busy_wait_command("latex $latex_file 1>/dev/null 2>/dev/null",
 				     "for $status_statement second latex to repaginate",
-				     \%prog_state, $name_file);
+				     \%prog_state, $name_file,$busy_wait_timeout);
 		  &busy_wait_command("latex $latex_file 1>/dev/null 2>/dev/null",
 				     "for $status_statement third latex to repaginate",
-				     \%prog_state, $name_file);
+				     \%prog_state, $name_file,$busy_wait_timeout);
 	      }
 	      if ($tableofindex eq 'yes') {
 		  my $idxname = $latex_file;
@@ -529,7 +530,7 @@ foreach $texfile (@texfile) {
 				     \%prog_state, $idxname);
 		  &busy_wait_command("latex $latex_file 1>/dev/null 2>/dev/null",
 				     "for $status_statement now Recreting index (latex)",
-				     \%prog_state, $dvi_file);
+				     \%prog_state, $dvi_file,$busy_wait_timeout);
 
 	      }
 	      &busy_wait_command("$comma $name_file 1>/dev/null 2>/dev/null",
@@ -619,7 +620,7 @@ foreach $texfile (@texfile) {
               $logfilename=~s{^\Q$perlvar{'lonPrtDir'}\E}{/prtspool};
 	      print "<a href=\"$logfilename\">Your log file </a></big></b>";
 	      print "\n";
-	      #link tooriginal LaTeX file (included according Michael Hamlin desire)
+	      #link to original LaTeX file
 	      my $tex_temporary_file=IO::File->new($texfile) || die "Couldn't open tex file $texfile for reading: $!\n";
 	      my @tex_content_of_file = <$tex_temporary_file>;
 	      close $tex_temporary_file; 
@@ -685,14 +686,14 @@ foreach $texfile (@texfile) {
 	      &repaginate($new_name_file, $latex_file,  $numberofcolumns);
 	      &busy_wait_command("latex $latex_file 1>/dev/null 2>/dev/null",
 				 "for $status_statement first latex to repaginate",
-				 \%prog_state, $name_file);
+				 \%prog_state, $name_file, $busy_wait_timeout);
 	      if ($tableofcontents eq 'yes') {
 		  &busy_wait_command("latex $latex_file 1>/dev/null 2>/dev/null",
 				     "for $status_statement second latex to repaginate",
-				     \%prog_state, $name_file);
+				     \%prog_state, $name_file,  $busy_wait_timeout);
 		  &busy_wait_command("latex $latex_file 1>/dev/null 2>/dev/null",
 				     "for $status_statement third latex to repaginate",
-				     \%prog_state, $name_file);
+				     \%prog_state, $name_file, $busy_wait_timeout);
 	      }
 	      if ($tableofindex eq 'yes') {
 		  my $idxname = $latex_file;
@@ -702,7 +703,7 @@ foreach $texfile (@texfile) {
 				     \%prog_state, $idxname);
 		  &busy_wait_command("latex $latex_file 1>/dev/null 2>/dev/null",
 				     "for $status_statement now Recreting index (latex)",
-				     \%prog_state, $dvi_file);
+				     \%prog_state, $dvi_file, $busy_wait_timeout);
 	      }
 	      &busy_wait_command("$comma $name_file 1>/dev/null 2>/dev/null",
 				 "for $status_statement dvips to repaginate",
@@ -794,9 +795,17 @@ my $done;
 sub REAPER {
     $done=1;
 }
-
+#
+#  Execute a command updating the status window as the command's
+#  output file builds up (at intervals of a second).
+#
+#   If the timeout argument defined, then if that many seconds
+#   elapses without an increase in the size of the output file,
+#   the command will be killed (this deals with the case when
+#   latex crawls into an infinite loop).
+#
 sub busy_wait_command {
-    my ($command,$message,$progress_win,$output_file)=@_;
+    my ($command,$message,$progress_win,$output_file, $timeout)=@_;
     
     $SIG{CHLD} = \&REAPER;
     $done=0;
@@ -804,12 +813,30 @@ sub busy_wait_command {
     if ($advanced_role) {
 	&Apache::lonhtmlcommon::Update_PrgWin('',$progress_win,$message);
     }
+    my $last_size      = 0;
+    my $unchanged_time = 0;
     while(!$done) {
 	sleep 1;
 	my $extra_msg;
 	if ($output_file) {
 	    my $size=(stat($output_file))[7];
 	    $extra_msg=", $size bytes generated";
+	    if ($size == $last_size) {
+		$unchanged_time++;
+		if ($timeout && ($unchanged_time > $timeout)) {
+		    print "<h1>Operation timed out!</h1>\n";
+		    print "<p>Executing $command, the output file $output_file did not grow\n";
+		    print "after $timeout seconds.  This <em>may</em> indicate $command\n";
+		    print "is in an infinite loop.\n";
+		    print "See if printing fewer copies helps.  Please contact LON-CAPA\n";
+		    print "support about this in any event.";
+		    print "</p>";
+		    kill(9, $pid); # Reaper will do the rest...I hope there's errors in the log.
+		}
+	    } else {
+		$last_size      = $size;
+		$unchanged_time = 0;
+	    }
 	}
 	if ($advanced_role) {
 	    &Apache::lonhtmlcommon::Update_PrgWin('',$progress_win,