# The GS package contains a wrapper scripts to call the Ghostscript
# program from within perl.
#

package GS;

# define these locations
$tmpdir = '/tmp';
$gsbin = '/usr/local/bin/gs';

# PS2PDF - 
# usage:  $PDFdata = GS::PS2PDF($PSdata);
# given a scalar containing postscript data, 
# return a scalar containing PDF data.
# returns nothing ("") on failure

sub PS2PDF {
   my $ps = shift;
   my $pdf = "";
   my $infile = "$tmpdir/$$.ps";
   my $outfile = "$tmpdir/$$.pdf";

   # first we try to write a file containing the PDF data
   if (open(PS,">$infile")) {
      print PS $ps;
      close(PS);
   } else {
      return("");
   }

   # then run ghostscript
   my $command = "$gsbin -q -dNOPAUSE -dBATCH -sDEVICE=pdfwrite "
               . "-sOutputFile=$outfile -c save pop -f $infile "
               . "> /dev/null 2>&1";
   if (system($command)) {  # non-zero means execution failed
      unlink $infile, $outfile;
      return "";
   }

   # then read in results
   if (open(PDF,$outfile)) {
      my $buf;
      while (read PDF, $buf, 10240) { $pdf .= $buf; }
      close(PDF);
   } else {
      unlink $infile, $outfile;
      return "";
   }

   # remove temp files and return
   unlink $infile, $outfile;
   return $pdf;
}

1;