Add event handlers (#1)

* Add rx event handlers

* Fix compile errors and add constness

* Pass sender id

* Change api interface

* Revert changes

* Add filter fifo

Src/mmr_can_events.c

@@ -0,0 +1,58 @@
+#include "mmr_can.h"
+#include "mmr_can_events.h"
+
+
+static const MmrCanEventList *_rxEvents = NULL;
+
+
+static void __handleCanRxInterrupt(CanHandle *hcan);
+static void __invokeAll(const MmrCanEventList *events, MmrCanEvent *event);
+static void __maybeInvoke(const MmrCanEventHandler handler, MmrCanEvent *event);
+
+
+void MMR_CAN_InitRxHandlers(const MmrCanEventList *rxEvents) {
+  _rxEvents = rxEvents;
+}
+
+
+static void __handleCanRxInterrupt(CanHandle *hcan) {
+  static CanRxHeader rxHeader = {};
+  static CanRxBuffer rxData = {};
+
+  HAL_CAN_GetRxMessage(hcan, MMR_CAN_RX_FIFO, &rxHeader, rxData);
+
+  MmrCanEvent event = {
+    .senderId = rxHeader.StdId,
+    .message = rxData,
+  };
+
+  __invokeAll(_rxEvents, &event);
+}
+
+static void __invokeAll(const MmrCanEventList *events, MmrCanEvent *event) {
+  if (!events) {
+    return;
+  }
+
+  short i;
+  for (i = 0; i < events->count; i++) {
+    __maybeInvoke(events->handlers[i], event);
+  }
+}
+
+static always_inline void __maybeInvoke(const MmrCanEventHandler handler, MmrCanEvent *event) {
+  if (handler) {
+    handler(event);
+  }
+}
+
+
+#if MMR_CAN_RX_FIFO == CAN_RX_FIFO0
+void HAL_CAN_RxFifo0MsgPendingCallback(CanHandle *hcan) {
+  __handleCanRxInterrupt(hcan);
+}
+#elif MMR_CAN_RX_FIFO == CAN_RX_FIFO1
+void HAL_CAN_RxFifo1MsgPendingCallback(CanHandle *hcan) {
+  __handleCanRxInterrupt(hcan);
+}
+#endif