pbio/sys/main: Fix shutdown animation sometimes not visible.

When shutting down due to Bluetooth getting stuck, we were not showing the shutdown animation because the shutdown request state was never set, and the program run state was not cleared.

This made it look like a full system crash, when it was still a clean shutdown.

Author: laurensvalk

CHANGELOG.md

@@ -26,6 +26,7 @@
 - Fixed internal rounding error that could could cause a Drive Base to be 1 mm
   off after driving 3 meters, depending on configuration parameters ([support#2500]).
 - Fixed Powered Up remote light getting the wrong color ([support#2497]).
+- Fix shutdown animation not visible when shutting down due to Bluetooth glitches.
 
 [support#1962]: https://github.com/pybricks/support/issues/1962
 [support#2468]: https://github.com/pybricks/support/issues/2468

lib/pbio/sys/core.c

@@ -87,6 +87,9 @@ void pbsys_init(void) {
 
 void pbsys_deinit(void) {
 
+    // Used by status indications during shutdown.
+    pbsys_status_set(PBIO_PYBRICKS_STATUS_SHUTDOWN_REQUEST);
+
     pbio_os_process_make_request(&pbsys_system_poll_process, PBIO_OS_PROCESS_REQUEST_TYPE_CANCEL);
 
     pbsys_storage_deinit();

lib/pbio/sys/main.c

@@ -112,11 +112,6 @@ void pbsys_main(void) {
 
         // Stop motors, user animations, user bluetooth activity, etc.
         err = pbio_main_stop_application_resources();
-        if (err != PBIO_SUCCESS) {
-            // If we couldn't get the system back in a normal state, proceed
-            // towards shutdown.
-            break;
-        }
 
         // Get system back in idle state.
         pbsys_status_clear(PBIO_PYBRICKS_STATUS_USER_PROGRAM_RUNNING);
@@ -129,6 +124,13 @@ void pbsys_main(void) {
         while (pbio_os_run_processes_once()) {
         }
 
+        if (err != PBIO_SUCCESS) {
+            // If we couldn't get the system back in a normal state after
+            // running a program, proceed towards shutdown. In practice, this
+            // only happens for rare Bluetooth glitches on some platforms.
+            break;
+        }
+
         // Finalize application now that system resources are safely closed.
         pbsys_main_run_program_cleanup();
     }