start working on timer subsys

1 files changed, 47 insertions, 0 deletions

diff --git a/include/apos/timer.h b/include/apos/timer.h
new file mode 100644
index 0000000..ea5bd03
--- /dev/null
+++ b/include/apos/timer.h
@@ -0,0 +1,47 @@
+#ifndef APOS_TIMER_H
+#define APOS_TIMER_H
+
+#include <apos/types.h>
+
+typedef size_t ticks_t;
+/* whichever time unit we're dealing with */
+typedef size_t tunit_t;
+
+struct timer {
+	id_t tid;
+	id_t cid;
+
+	ticks_t ticks;
+};
+
+void init_timer();
+
+/* set up timer interrupt ticks from now */
+id_t new_rel_timer(id_t tid, ticks_t ticks);
+/* set up timer interrupt at ticks (from startup I suppose) */
+id_t new_abs_timer(id_t tid, ticks_t ticks);
+
+struct timer *newest_timer();
+struct timer *find_timer(id_t cid);
+void remove_timer(struct timer *);
+
+ticks_t nsecs_to_ticks(tunit_t nsecs);
+
+static inline ticks_t usecs_to_ticks(tunit_t usecs)
+{
+	return nsecs_to_ticks(usecs * 1000);
+}
+
+static inline ticks_t msecs_to_ticks(tunit_t msecs)
+{
+	return usecs_to_ticks(msecs * 1000);
+}
+
+/* TODO: likely not a problem on 64bit systems, not sure how to handle situation on
+ * 32bit */
+static inline ticks_t secs_to_ticks(tunit_t secs)
+{
+	return msecs_to_ticks(secs * 1000);
+}
+
+#endif /* APOS_TIMER_H */