Remove `SslRef::compression`

        unsafe { ffi::SSL_pending(self.as_ptr()) as usize }

    }

    /// Returns the compression method currently in use.

    ///

    /// This corresponds to `SSL_get_current_compression`.

    pub fn compression(&self) -> Option<&str> {

        self._compression()

    }

    #[cfg(not(osslconf = "OPENSSL_NO_COMP"))]

    fn _compression(&self) -> Option<&str> {

        unsafe {

            let ptr = ffi::SSL_get_current_compression(self.as_ptr());

            if ptr == ptr::null() {

                return None;

            }

            let meth = ffi::SSL_COMP_get_name(ptr);

            Some(str::from_utf8(CStr::from_ptr(meth as *const _).to_bytes()).unwrap())

        }

    }

    #[cfg(osslconf = "OPENSSL_NO_COMP")]

    fn _compression(&self) -> Option<&str> {

        None

    }

    /// Returns the servername sent by the client via Server Name Indication (SNI).

    ///

    /// It is only useful on the server side.