--- loncom/cgi/barcode.png	2001/08/15 14:03:15	1.2
+++ loncom/cgi/barcode.png	2001/12/11 19:32:03	1.5
@@ -1,11 +1,37 @@
 #!/usr/bin/perl
 
 # The LearningOnline Network with CAPA
+# barcode.gif - A CGI script that dynamically outputs a barcode.
+#
+# $Id: barcode.png,v 1.5 2001/12/11 19:32:03 harris41 Exp $
+#
+# Copyright Michigan State University Board of Trustees
+#
+# This file is part of the LearningOnline Network with CAPA (LON-CAPA).
+#
+# LON-CAPA is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# LON-CAPA is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with LON-CAPA; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+#
+# /home/httpd/html/adm/gpl.txt
+#
+# http://www.lon-capa.org/
+#
 # Scott Harrison
 # YEAR=2001
-# 8/15
-
-# A CGI script that dynamically outputs a barcode.
+# 8/15,9/28,12/11
+#
+###
 
 # I'm using format=Code39.
 # The valid formats are
@@ -32,12 +58,19 @@ Content-type: image/gif
 
 END
 
+unless(defined($ENV{'form.encode'}) and length($ENV{'form.encode'})) {
+    $ENV{'form.encode'}='***ERROR***UNDEFINED***';
+}
+
 my $oGdBar=GD::Barcode::Code39->new($ENV{'form.encode'});
-warn($GD::Barcode::errStr);
+if ($GD::Barcode::errStr or !defined($oGdBar)) {
+    warn($GD::Barcode::errStr);
+    $oGdBar=GD::Barcode::Code39->new('***ERROR***INVALID***');
+}
 my $bindata=$oGdBar->plot->png; # create barcode image
 undef $oGdBar;
 binmode(STDOUT);
-open OUT,"|pngtopnm|ppmtogif"; # convert into a gif image
+open OUT,"|pngtopnm|ppmtogif 2>/dev/null"; # convert into gif image
 print OUT $bindata; # output image
 $|=1; # be sure to flush before closing
 close OUT;