#!/home/shishir/perl5.001m/perl5 require "common.pl"; use GD; $webmaster = "shishir\@bu\.edu"; $document_root = "/home/shishir/httpd_1.4.2/public"; &read_data_file (*slices, *slices_color, *slices_message); $no_slices = &remove_empty_slices(); if ($no_slices == -1) { &no_data (); } else { $nongraphic_browsers = 'Lynx|CERN-LineMode'; $client_browser = $ENV{'HTTP_USER_AGENT'}; if ($client_browser =~ /$nongraphic_browsers/) { &text_results (); } else { &draw_pie (); } } exit(0); sub no_data { print "Content-type: text/html", "\n\n"; print < Results

No Results Available

Sorry, no one has participated in this survey up to this point. As a result, there is no data avilable. Try back later.

End_of_Message } sub draw_pie { local ( $legend_rect_size, $legend_rect, $max_length, $max_height, $pie_indent, $pie_length, $pie_height, $radius, @origin, $legend_indent, $legend_rect_to_text, $deg_to_rad, $image, $white, $black, $red, $yellow, $green, $blue, $orange, $percent, $loop, $degrees, $x, $y, $legend_x, $legend_y, $legend_rect_y, $text, $message); $legend_rect_size = 10; $legend_rect = $legend_rect_size * 2; $max_length = 450; if ($no_slices > 8) { $max_height = 200 + ( ($no_slices - 8) * $legend_rect ); } else { $max_height = 200; } $pie_indent = 10; $pie_length = $pie_height = 200; $radius = $pie_height / 2; @origin = ($radius + $pie_indent, $max_height / 2); $legend_indent = $pie_length + 40; $legend_rect_to_text = 25; $deg_to_rad = (atan2 (1, 1) * 4) / 180; $image = new GD::Image ($max_length, $max_height); $white = $image->colorAllocate (255, 255, 255); $black = $image->colorAllocate(0, 0, 0); $red = $image->colorAllocate (255, 0, 0); $yellow = $image->colorAllocate (255, 255, 0); $green = $image->colorAllocate(0, 255, 0); $blue = $image->colorAllocate(0, 0, 255); $orange = $image->colorAllocate(255, 165, 0); grep ($_ = eval("\$$_"), @slices_color); $image->arc (@origin, $pie_length, $pie_height, 0, 360, $black); $percent = 0; for ($loop=0; $loop <= $no_slices; $loop++) { $percent += $slices[$loop]; $degrees = int ($percent * 360) * $deg_to_rad; $image->line ( $origin[0], $origin[1], $origin[0] + ($radius * cos ($degrees)), $origin[1] + ($radius * sin ($degrees)), $slices_color[$loop] ); } $percent = 0; for ($loop=0; $loop <= $no_slices; $loop++) { $percent += $slices[$loop]; $degrees = int (($percent * 360) - 1) * $deg_to_rad; $x = $origin[0] + ( ($radius - 10) * cos ($degrees) ); $y = $origin[1] + ( ($radius - 10) * sin ($degrees) ); $image->fill ($x, $y, $slices_color[$loop]); } $legend_x = $legend_indent; $legend_y = ( $max_height - ($no_slices * $legend_rect) - ($legend_rect * 0.75) ) / 2; for ($loop=0; $loop <= $no_slices; $loop++) { $legend_rect_y = $legend_y + ($loop * $legend_rect); $text = pack ("A18", $slices_message[$loop]); $message = sprintf ("%s (%4.2f%%)", $text, $slices[$loop] * 100); $image->filledRectangle ( $legend_x, $legend_rect_y, $legend_x + $legend_rect_size, $legend_rect_y + $legend_rect_size, $slices_color[$loop] ); $image->string ( gdSmallFont, $legend_x + $legend_rect_to_text, $legend_rect_y, $message, $black ); } $image->transparent($white); $| = 1; print "Content-type: image/gif", "\n\n"; print $image->gif; } sub text_results { local ($text, $message, $loop); print "Content-type: text/html", "\n\n"; print < Results

Results

End_of_Results

    for ($loop=0; $loop <= $no_slices; $loop++) {
        $text = pack ("A18", $slices_message[$loop]);
        $message = sprintf ("%s (%4.2f%%)", $text, 
                            $slices[$loop] * 100);

        print $message, "\n";
    }

    print "

", "\n"; print "", "\n"; } sub read_data_file { local (*slices, *slices_color, *slices_message) = @_; local (@line, $total_votes, $poll_file, $loop, $exclusive_lock, $unlock); $exclusive_lock = 2; $unlock = 8; if ($ENV{'PATH_INFO'}) { $poll_file = $document_root . $ENV{'PATH_INFO'}; } else { &return_error (500, "Poll Data File Error", "A poll data file has to be specified."); } if ( open (POLL, "<" . $poll_file) ) { flock (POLL, $exclusive_lock); for ($loop=0; $loop < 3; $loop++) { $line[$loop] = ; $line[$loop] =~ s/\n$//; } @slices_message = split ("::", $line[0]); @slices = split ("::", $line[1]); @slices_color = split ("::", $line[2]); flock (POLL, $unlock); close (POLL); $total_votes = 0; for ($loop=0; $loop <= $#slices; $loop++) { $total_votes += $slices[$loop]; } if ($total_votes > 0) { grep ($_ = ($_ / $total_votes), @slices); } } else { &return_error (500, "Poll Data File Error", "Cannot read from the poll data file [$poll_file]."); } } sub remove_empty_slices { local ($loop) = 0; while (defined ($slices[$loop])) { if ($slices[$loop] <= 0.0) { splice(@slices, $loop, 1); splice(@slices_color, $loop, 1); splice(@slices_message, $loop, 1); } else { $loop++; } } return ($#slices); }