Function proto_tree_add_bytes_with_length 

pub unsafe extern "C" fn proto_tree_add_bytes_with_length(
    tree: *mut proto_tree,
    hfindex: c_int,
    tvb: *mut tvbuff_t,
    start: gint,
    length: gint,
    start_ptr: *const guint8,
    ptr_length: gint,
) -> *mut proto_item