io_pin_remap fixes for the Arduino Nano ESP32 (espressif#8489)

* io_pin_remap: fix tone() function mapping declaration

Since tone() can have either 2 or 3 parameters, pass any argument after the
first to the actual function implementation.

* io_pin_remap: add sanity checks to the core build

Building with BOARD_HAS_PIN_REMAP but without setting ARDUINO_CORE_BUILD
on core files is absolutely forbidden, as this would lead to multiple
pin remappings being silently applied on the same numbers.

Also advise the user when, on a board that has a custom pin mapping,
- the core is being built without pin mapping support, or
- the user explictly asked to use GPIO pin numbers.

cores/esp32/io_pin_remap.h

@@ -18,7 +18,7 @@ int8_t digitalPinFromGPIONumber(int8_t gpioPin);
 #define pulseInLong(pin, state, timeout)    pulseInLong(digitalPinToGPIONumber(pin), state, timeout)
 #define pulseIn(pin, state, timeout)        pulseIn(digitalPinToGPIONumber(pin), state, timeout)
 #define noTone(_pin)                        noTone(digitalPinToGPIONumber(_pin))
-#define tone(_pin, frequency, duration)     tone(digitalPinToGPIONumber(_pin), frequency, duration)
+#define tone(_pin, args...)                 tone(digitalPinToGPIONumber(_pin), args)
 
 // cores/esp32/esp32-hal.h
 #define analogGetChannel(pin)       analogGetChannel(digitalPinToGPIONumber(pin))

variants/arduino_nano_nora/io_pin_remap.cpp

@@ -1,4 +1,20 @@
-#ifndef BOARD_USES_HW_GPIO_NUMBERS
+#if defined(BOARD_HAS_PIN_REMAP) && !defined(ARDUINO_CORE_BUILD)
+// -DARDUINO_CORE_BUILD must be set for core files only, to avoid extra
+// remapping steps that would create all sorts of issues in the core.
+// Removing -DBOARD_HAS_PIN_REMAP at least does correctly restore the
+// use of GPIO numbers in the API.
+#error This build system is not supported. Please rebuild without BOARD_HAS_PIN_REMAP.
+#endif
+
+#if !defined(BOARD_HAS_PIN_REMAP)
+// This board uses pin mapping but the build system has disabled it
+#warning The build system forces the Arduino API to use GPIO numbers on a board that has custom pin mapping.
+#elif defined(BOARD_USES_HW_GPIO_NUMBERS)
+// The user has chosen to disable pin mappin.
+#warning The Arduino API will use GPIO numbers for this build.
+#endif
+
+#if defined(BOARD_HAS_PIN_REMAP) && !defined(BOARD_USES_HW_GPIO_NUMBERS)
 
 #include "Arduino.h"