Make delay() and yield() overridable, and add pluggable loop_end()

Author: dok-net

cores/esp32/esp32-hal-misc.c

@@ -44,11 +44,13 @@ float temperatureRead()
     return (temprature_sens_read() - 32) / 1.8;
 }
 
-void yield()
+void __yield()
 {
     vPortYield();
 }
 
+void yield() __attribute__ ((weak, alias("__yield")));
+
 #if CONFIG_AUTOSTART_ARDUINO
 
 extern TaskHandle_t loopTaskHandle;
@@ -139,11 +141,13 @@ unsigned long IRAM_ATTR millis()
     return (unsigned long) (esp_timer_get_time() / 1000ULL);
 }
 
-void delay(uint32_t ms)
+void __delay(uint32_t ms)
 {
     vTaskDelay(ms / portTICK_PERIOD_MS);
 }
 
+void delay(uint32_t ms) __attribute__ ((weak, alias("__delay"))); 
+
 void IRAM_ATTR delayMicroseconds(uint32_t us)
 {
     uint32_t m = micros();

cores/esp32/main.cpp

@@ -9,6 +9,13 @@ TaskHandle_t loopTaskHandle = NULL;
 
 bool loopTaskWDTEnabled;
 
+extern "C" void __loop_end(void)
+{
+    /* do nothing by default */
+}
+
+extern "C" void loop_end(void) __attribute__((weak, alias("__loop_end")));
+
 void loopTask(void *pvParameters)
 {
     setup();
@@ -17,6 +24,7 @@ void loopTask(void *pvParameters)
             esp_task_wdt_reset();
         }
         loop();
+        loop_end();
     }
 }