print header( -charset=>'utf8' );
my $article = param('select') || "Αρχική Σελίδα!";

my @files = glob "$ENV{'DOCUMENT_ROOT'}/data/text/*.txt";
my @menu_files = map m{([^/]+)\.txt}, @files;
Encode::from_to($_, 'ISO-8859-7', 'utf8') for @menu_files;

if ( param('select') )  {  #If user selected an item from the drop down menu

   $article = decode( 'utf8', $article );
   unless ( grep  /^\Q$_\E$/, @menu_files )  #Unless user selection doesn't match one of the valid filenames within @display_files
   {
......

##</code><code>##

print header( -charset=>'utf8' );
my $article = param('select') || "&#913;&#961;&#967;&#953;&#954;&#942; &#931;&#949;&#955;&#943;&#948;&#945;!";

my @files = glob "$ENV{'DOCUMENT_ROOT'}/data/text/*.txt";
my @menu_files = map m{([^/]+)\.txt}, @files;
Encode::from_to($_, 'ISO-8859-7', 'utf8') for @menu_files;


if ( param('select') )  {  #If user selected an item from the drop down menu
   
#No alternation to utf8 encoding or decoding is needed here....the returned value is consisted of utf8 flag and contains wide characters as the original

   unless ( grep  /^\Q$_\E$/, @menu_files )  #Unless user selection doesn't match one of the valid filenames within @display_files
   {
      if( param('select') =~ /\0/ )
      {
         $article = "*Null Byte Injection* attempted & logged!";
         print br() x 2, h1( {class=>'big'}, $article );
      }
      if( param('select') =~ /\/\.\./ )
      {  
         $article = "*Backwards Directory Traversal* attempted & logged!";
         print br() x 2, h1( {class=>'big'}, $article );
      }

      $select = $db->prepare( "UPDATE guestlog SET article=?, date=?, counter=counter+1 WHERE host=?" );
      $select->execute( $article, $date, $host );
      
      exit 0;
   }

   Encode::from_to($article, 'utf8', 'ISO-8859-7');  #Convert user selected filename to greek-iso so it can be opened

   open FILE, "<$ENV{'DOCUMENT_ROOT'}/data/text/$article.txt" or die $!;
      local $/;      
      $data = <FILE>;
   close FILE;
   
   Encode::from_to($article, 'ISO-8859-7', 'utf8');  #Convert user selected filename back to utf8 before inserting into db 

   $select = $db->prepare( "UPDATE guestlog SET article=?, date=?, counter=counter+1 WHERE host=?" );
   $select->execute( $article, $date, $host );
}
else {

##</code><code>##

for ($data) {  #Replace special chars like single & double quotes to its literally values
   s/\n/\\n/g;
   s/'/\\'/g;
   s/"/\"/g;
   tr/\cM//d;
}

##</code><code>##

print header( -charset=>'utf8' );
my $article = param('select') || "&#913;&#961;&#967;&#953;&#954;&#942; &#931;&#949;&#955;&#943;&#948;&#945;!";

my @files = glob "$ENV{'DOCUMENT_ROOT'}/data/text/*.txt";
my @menu_files = map m{([^/]+)\.txt}, @files;
Encode::from_to($_, 'ISO-8859-7', 'utf8') for @menu_files;

if ( param('select') )  {  #If user selected an item from the drop down menu

   $article = encode( 'utf8', $article );
   unless ( grep  /^\Q$_\E$/, @menu_files )  #Unless user selection doesn't match one of the valid filenames within @display_files
   {
......