pub type BER_MEMCALLOC_FN = Option<unsafe extern "C" fn(n: ber_len_t, size: ber_len_t, ctx: *mut c_void) -> *mut c_void>;
pub enum BER_MEMCALLOC_FN { None, Some(unsafe extern "C" fn(u64, u64, *mut c_void) -> *mut c_void), }
No value.
Some value of type T.
T