<?php
if (!function_exists ( 'gzdecode' )) {
	function gzdecode($data){

	$flags = ord ( substr ( $data, 3, 1 ) );
	$headerlen = 10;
	$extralen = 0;
	$filenamelen = 0;
	if ($flags & 4) {
		$extralen = unpack ( 'v', substr ( $data, 10, 2 ) );
		$extralen = $extralen [1];
		$headerlen += 2 + $extralen;
	}
	if ($flags & 8) // Filename 
		$headerlen = strpos ( $data, chr ( 0 ), $headerlen ) + 1;
	if ($flags & 16) // Comment 
		$headerlen = strpos ( $data, chr ( 0 ), $headerlen ) + 1;
	if ($flags & 2) // CRC at end of file 
		$headerlen += 2;
	$unpacked = @gzinflate ( substr ( $data, $headerlen ) );
	if ($unpacked === FALSE)
		$unpacked = $data;
	return $unpacked;

	}
}

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