canio: Run background tasks while waiting for message reception

Closes: adafruit#5004

Author: jepler

ports/atmel-samd/common-hal/canio/Listener.c

@@ -356,6 +356,11 @@ mp_obj_t common_hal_canio_listener_receive(canio_listener_obj_t *self) {
             if (supervisor_ticks_ms64() > deadline) {
                 return NULL;
             }
+            RUN_BACKGROUND_TASKS;
+            // Allow user to break out of a timeout with a KeyboardInterrupt.
+            if ( mp_hal_is_interrupted() ) {
+                return NULL;
+            }
         } while (!common_hal_canio_listener_in_waiting(self));
     }
     int index = self->hw->RXFS.bit.F0GI;

ports/stm/common-hal/canio/Listener.c

@@ -30,6 +30,8 @@
 #include "py/obj.h"
 #include "py/runtime.h"
 
+#include "lib/utils/interrupt_char.h"
+
 #include "common-hal/canio/__init__.h"
 #include "common-hal/canio/Listener.h"
 #include "shared-bindings/canio/Listener.h"
@@ -272,6 +274,11 @@ mp_obj_t common_hal_canio_listener_receive(canio_listener_obj_t *self) {
             if (supervisor_ticks_ms64() > deadline) {
                 return NULL;
             }
+            RUN_BACKGROUND_TASKS;
+            // Allow user to break out of a timeout with a KeyboardInterrupt.
+            if ( mp_hal_is_interrupted() ) {
+                return NULL;
+            }
         } while (!common_hal_canio_listener_in_waiting(self));
     }