if {{ name }}.is_null() {
        set_last_error(1, "Null pointer passed for parameter '{{ name }}'");
        {{ fail_ret }}
    }
    // SAFETY: null check above guarantees {{ name }} is a valid pointer; string is valid UTF-8 from caller.
    let {{ rs_name }} = match unsafe { CStr::from_ptr({{ name }}) }.to_str() {
        Ok(s) => s.to_string(),
        Err(_) => {
            set_last_error(1, "Invalid UTF-8 in parameter '{{ name }}'");
            {{ fail_ret }}
        }
    };
