Track if any tasks are stil running and if not then panic

Kernel.cpp

@@ -113,12 +113,16 @@ void Kernel_tick()
   last_tick = millis();
 
   unsigned long next_tick_due = ULONG_MAX;
+  int running_tasks = 0;
+  int last_exit_code = 0;
   
   for (int i=0; i<MAX_TASKS; i++)
   {
     // If the task is initialized (non-zero PID) and is marked as running
     if (tasks[i].pid != 0 && tasks[i].running == true)
     {
+      // Make sure we found at least one active process, because if not we dead.
+      running_tasks++;
 
       // Check if this tick's duration will push us over the run interval and if so set the TICK signal
       if (tasks[i].run_accumulator + duration > tasks[i].run_interval)
@@ -149,19 +153,29 @@ void Kernel_tick()
           tasks[i].running = false;
           // Store the exit code
           tasks[i].exit_code = task_return;
+          // Actually it's not running...
+          running_tasks--;
+          last_exit_code = task_return;
         }
       }
       
 
       // Check each task to see if it's the one scheduled to run on the next closest tick, and track it
       // so we can put the processor to sleep until then.
-      if (tasks[i].run_interval - tasks[i].run_accumulator < next_tick_due)
+      if (tasks[i].running && tasks[i].run_interval - tasks[i].run_accumulator < next_tick_due)
       {
         next_tick_due = tasks[i].run_interval - tasks[i].run_accumulator;
       }
     }
   }
 
+  if (running_tasks == 0)
+  {
+    char panic_msg[255];
+    sprintf(panic_msg, "All processes exited! Last exit code: %d", last_exit_code);
+    Kernel_panic(panic_msg);
+  }
+
   // Put processor to sleep until the next scheduled run of a task
   // Leave the home button enabled to force a wake-up before then
   esp_sleep_enable_timer_wakeup(next_tick_due * 1000);