kernel: new event abstraction

kernel-src/include/event.h

@@ -0,0 +1,12 @@
+#ifndef _EVENT_H
+#define _EVENT_H
+
+#include <semaphore.h>
+typedef semaphore_t event_t;
+
+int event_wait(event_t *event, bool interruptible);
+void event_signal(event_t *event);
+
+#define EVENT_INIT(x) SEMAPHORE_INIT(x, 0);
+
+#endif

kernel-src/lib/event.c

@@ -0,0 +1,19 @@
+#include <event.h>
+
+// TODO while this works, it is built upon semaphores and might have some race conditions
+
+int event_wait(event_t *event, bool interruptible) {
+	int e = semaphore_wait(event, interruptible);
+	if (e)
+		return e;
+
+	if (semaphore_haswaiters(event))
+		semaphore_signal(event);
+
+	return 0;
+}
+
+void event_signal(event_t *event) {
+	if (semaphore_haswaiters(event))
+		semaphore_signal(event);
+}