Function faulthandler_user_signal

crates/stdlib/src/faulthandler.rs:1053–1082

(signum: libc::c_int)

    #[cfg(unix)]
    extern "C" fn faulthandler_user_signal(signum: libc::c_int) {
        let save_errno = get_errno();

        let user = match user_signals::get_user_signal(signum as usize) {
            Some(u) if u.enabled => u,
            _ => return,
        };

        faulthandler_dump_traceback(user.fd, user.all_threads);

        if user.chain {
            // Restore the previous handler and re-raise
            unsafe {
                libc::sigaction(signum, &user.previous, core::ptr::null_mut());
            }
            set_errno(save_errno);
            unsafe {
                libc::raise(signum);
            }
            // Re-install our handler with the same flags as register()
            let save_errno2 = get_errno();
            unsafe {
                let mut action: libc::sigaction = core::mem::zeroed();
                action.sa_sigaction = faulthandler_user_signal as *const () as libc::sighandler_t;
                action.sa_flags = libc::SA_NODEFER;
                libc::sigaction(signum, &action, core::ptr::null_mut());
            }
            set_errno(save_errno2);
        }
    }

    #[cfg(unix)]
    fn check_signum(signum: i32, vm: &VirtualMachine) -> PyResult<()> {