Function sioul_event_decide 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn sioul_event_decide(
    key: *const c_char,
) -> *mut c_char

decide, for Java (android/main.cpp); a panic answers null, and Java shows the words it was given with the list rather than nothing. Given back to sioul_string_free.

Safety

key is null, or a zero-terminated text valid for the call.