+/**
+ * Wait for multiple events
+ *
+ * On success return the offset in the \a evs vector of the Event that
+ * happened, -1 if the timeout expires.
+ *
+ * NOTE: timeout == 0 means no timeout.
+ */
+#if defined(CONFIG_KERN_SIGNALS) && CONFIG_KERN_SIGNALS
+INLINE int event_select(Event **evs, int n, ticks_t timeout)
+{
+ sigmask_t mask = (1 << n) - 1;
+ int i;
+
+ ASSERT(n <= SIG_USER_MAX);
+ for (i = 0; i < n; i++)
+ {
+ Event *e = evs[i];
+ /* Map each event to a distinct signal bit */
+ event_initSignal(e, proc_current(), 1 << i);
+ }
+ mask = timeout ? sig_waitTimeout(mask, timeout) : sig_wait(mask);
+ i = UINT8_LOG2(mask);
+
+ return i < n ? i : -1;
+}
+#else
+INLINE int event_select(Event **evs, int n, ticks_t timeout)
+{
+ ticks_t end = timer_clock() + timeout;
+ int i;
+
+ while (1)
+ {
+ for (i = 0; i < n; i++)
+ {
+ Event *e = evs[i];
+ if (ACCESS_SAFE(e->Ev.Gen.completed) == true)
+ {
+ e->Ev.Gen.completed = false;
+ MEMORY_BARRIER;
+ return i;
+ }
+ }
+ if (timeout && TIMER_AFTER(timer_clock(), end))
+ break;
+ cpu_relax();
+ }
+ return -1;
+}
+#endif
+
+