Defined (1)

The class is defined in the following location(s).

/wp-includes/SimplePie/gzdecode.php  

class SimplePie_gzdecode 
{ 
    /** 
     * Compressed data 
     * 
     * @access private 
     * @var string 
     * @see gzdecode::$data 
     */ 
    var $compressed_data; 
 
    /** 
     * Size of compressed data 
     * 
     * @access private 
     * @var int 
     */ 
    var $compressed_size; 
 
    /** 
     * Minimum size of a valid gzip string 
     * 
     * @access private 
     * @var int 
     */ 
    var $min_compressed_size = 18; 
 
    /** 
     * Current position of pointer 
     * 
     * @access private 
     * @var int 
     */ 
    var $position = 0; 
 
    /** 
     * Flags (FLG) 
     * 
     * @access private 
     * @var int 
     */ 
    var $flags; 
 
    /** 
     * Uncompressed data 
     * 
     * @access public 
     * @see gzdecode::$compressed_data 
     * @var string 
     */ 
    var $data; 
 
    /** 
     * Modified time 
     * 
     * @access public 
     * @var int 
     */ 
    var $MTIME; 
 
    /** 
     * Extra Flags 
     * 
     * @access public 
     * @var int 
     */ 
    var $XFL; 
 
    /** 
     * Operating System 
     * 
     * @access public 
     * @var int 
     */ 
    var $OS; 
 
    /** 
     * Subfield ID 1 
     * 
     * @access public 
     * @see gzdecode::$extra_field 
     * @see gzdecode::$SI2 
     * @var string 
     */ 
    var $SI1; 
 
    /** 
     * Subfield ID 2 
     * 
     * @access public 
     * @see gzdecode::$extra_field 
     * @see gzdecode::$SI1 
     * @var string 
     */ 
    var $SI2; 
 
    /** 
     * Extra field content 
     * 
     * @access public 
     * @see gzdecode::$SI1 
     * @see gzdecode::$SI2 
     * @var string 
     */ 
    var $extra_field; 
 
    /** 
     * Original filename 
     * 
     * @access public 
     * @var string 
     */ 
    var $filename; 
 
    /** 
     * Human readable comment 
     * 
     * @access public 
     * @var string 
     */ 
    var $comment; 
 
    /** 
     * Don't allow anything to be set 
     * 
     * @param string $name 
     * @param mixed $value 
     */ 
    public function __set($name, $value) 
    { 
        trigger_error("Cannot write property $name", E_USER_ERROR); 
    } 
 
    /** 
     * Set the compressed string and related properties 
     * 
     * @param string $data 
     */ 
    public function __construct($data) 
    { 
        $this->compressed_data = $data; 
        $this->compressed_size = strlen($data); 
    } 
 
    /** 
     * Decode the GZIP stream 
     * 
     * @return bool Successfulness 
     */ 
    public function parse() 
    { 
        if ($this->compressed_size >= $this->min_compressed_size) 
        { 
            // Check ID1, ID2, and CM 
            if (substr($this->compressed_data, 0, 3) !== "\x1F\x8B\x08") 
            { 
                return false; 
            } 
 
            // Get the FLG (FLaGs) 
            $this->flags = ord($this->compressed_data[3]); 
 
            // FLG bits above (1 << 4) are reserved 
            if ($this->flags > 0x1F) 
            { 
                return false; 
            } 
 
            // Advance the pointer after the above 
            $this->position += 4; 
 
            // MTIME 
            $mtime = substr($this->compressed_data, $this->position, 4); 
            // Reverse the string if we're on a big-endian arch because l is the only signed long and is machine endianness 
            if (current(unpack('S', "\x00\x01")) === 1) 
            { 
                $mtime = strrev($mtime); 
            } 
            $this->MTIME = current(unpack('l', $mtime)); 
            $this->position += 4; 
 
            // Get the XFL (eXtra FLags) 
            $this->XFL = ord($this->compressed_data[$this->position++]); 
 
            // Get the OS (Operating System) 
            $this->OS = ord($this->compressed_data[$this->position++]); 
 
            // Parse the FEXTRA 
            if ($this->flags & 4) 
            { 
                // Read subfield IDs 
                $this->SI1 = $this->compressed_data[$this->position++]; 
                $this->SI2 = $this->compressed_data[$this->position++]; 
 
                // SI2 set to zero is reserved for future use 
                if ($this->SI2 === "\x00") 
                { 
                    return false; 
                } 
 
                // Get the length of the extra field 
                $len = current(unpack('v', substr($this->compressed_data, $this->position, 2))); 
                $this->position += 2; 
 
                // Check the length of the string is still valid 
                $this->min_compressed_size += $len + 4; 
                if ($this->compressed_size >= $this->min_compressed_size) 
                { 
                    // Set the extra field to the given data 
                    $this->extra_field = substr($this->compressed_data, $this->position, $len); 
                    $this->position += $len; 
                } 
                else 
                { 
                    return false; 
                } 
            } 
 
            // Parse the FNAME 
            if ($this->flags & 8) 
            { 
                // Get the length of the filename 
                $len = strcspn($this->compressed_data, "\x00", $this->position); 
 
                // Check the length of the string is still valid 
                $this->min_compressed_size += $len + 1; 
                if ($this->compressed_size >= $this->min_compressed_size) 
                { 
                    // Set the original filename to the given string 
                    $this->filename = substr($this->compressed_data, $this->position, $len); 
                    $this->position += $len + 1; 
                } 
                else 
                { 
                    return false; 
                } 
            } 
 
            // Parse the FCOMMENT 
            if ($this->flags & 16) 
            { 
                // Get the length of the comment 
                $len = strcspn($this->compressed_data, "\x00", $this->position); 
 
                // Check the length of the string is still valid 
                $this->min_compressed_size += $len + 1; 
                if ($this->compressed_size >= $this->min_compressed_size) 
                { 
                    // Set the original comment to the given string 
                    $this->comment = substr($this->compressed_data, $this->position, $len); 
                    $this->position += $len + 1; 
                } 
                else 
                { 
                    return false; 
                } 
            } 
 
            // Parse the FHCRC 
            if ($this->flags & 2) 
            { 
                // Check the length of the string is still valid 
                $this->min_compressed_size += $len + 2; 
                if ($this->compressed_size >= $this->min_compressed_size) 
                { 
                    // Read the CRC 
                    $crc = current(unpack('v', substr($this->compressed_data, $this->position, 2))); 
 
                    // Check the CRC matches 
                    if ((crc32(substr($this->compressed_data, 0, $this->position)) & 0xFFFF) === $crc) 
                    { 
                        $this->position += 2; 
                    } 
                    else 
                    { 
                        return false; 
                    } 
                } 
                else 
                { 
                    return false; 
                } 
            } 
 
            // Decompress the actual data 
            if (($this->data = gzinflate(substr($this->compressed_data, $this->position, -8))) === false) 
            { 
                return false; 
            } 
            else 
            { 
                $this->position = $this->compressed_size - 8; 
            } 
 
            // Check CRC of data 
            $crc = current(unpack('V', substr($this->compressed_data, $this->position, 4))); 
            $this->position += 4; 
            /**if (extension_loaded('hash') && sprintf('%u', current(unpack('V', hash('crc32b', $this->data)))) !== sprintf('%u', $crc)) 
            { 
                return false; 
            }*/ 
 
            // Check ISIZE of data 
            $isize = current(unpack('V', substr($this->compressed_data, $this->position, 4))); 
            $this->position += 4; 
            if (sprintf('%u', strlen($this->data) & 0xFFFFFFFF) !== sprintf('%u', $isize)) 
            { 
                return false; 
            } 
 
            // Wow, against all odds, we've actually got a valid gzip string 
            return true; 
        } 
        else 
        { 
            return false; 
        } 
    } 
}