pub unsafe extern "C" fn SSL_CTX_add_custom_ext(
ctx: *mut SSL_CTX,
ext_type: c_uint,
context: c_uint,
add_cb: SSL_custom_ext_add_cb_ex,
free_cb: SSL_custom_ext_free_cb_ex,
add_arg: *mut c_void,
parse_cb: SSL_custom_ext_parse_cb_ex,
parse_arg: *mut c_void,
) -> c_int