signal_cb(EV_P_ ev_signal *w, int revents)
{
    if (revents & EV_SIGNAL) {
        switch (w->signum) {
        case SIGINT:
        case SIGTERM:
            ev_unloop(EV_A_ EVUNLOOP_ALL);
        }
    }
}

The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.