[python] Rename micropython_port_should_interrupt to micropython_port_vm_hook_loop

python/port/helpers.cpp

@@ -4,15 +4,23 @@ extern "C" {
 #include "mphalport.h"
 }
 
-void micropython_port_should_interrupt() {
+void micropython_port_vm_hook_loop() {
+  /* This function is called very frequently by the MicroPython engine. We grab
+   * this opportunity to interrupt execution and/or refresh the display on
+   * platforms that need it. */
+
+  /* Doing too many things here slows down Python execution quite a lot. So we
+   * only do things once in a while and return as soon as possible otherwise. */
   static int c = 0;
   c++;
-  if (c%20000 != 0) {
+  if (c % 20000 != 0) {
     return;
   }
   c = 0;
+
+  /* Check if the user asked for an interruption from the keyboard */
   Ion::Keyboard::State scan = Ion::Keyboard::scan();
-  if (scan.keyDown((Ion::Keyboard::Key)mp_interrupt_char)) {
+  if (scan.keyDown(static_cast<Ion::Keyboard::Key>(mp_interrupt_char))) {
     mp_keyboard_interrupt();
   }
 }

python/port/helpers.h

@@ -5,9 +5,7 @@
 extern "C" {
 #endif
 
-/* should_interrupt effectively does something once every 20000 calls. It checks
- * if a key is down to raise an interruption flag. */
-void micropython_port_should_interrupt();
+void micropython_port_vm_hook_loop();
 
 #ifdef __cplusplus
 }

python/port/mpconfigport.h

@@ -90,7 +90,7 @@
 // (This scheme won't work if we want to mix Thumb and normal ARM code.)
 #define MICROPY_MAKE_POINTER_CALLABLE(p) (p)
 
-#define MICROPY_VM_HOOK_LOOP micropython_port_should_interrupt();
+#define MICROPY_VM_HOOK_LOOP micropython_port_vm_hook_loop();
 
 typedef intptr_t mp_int_t; // must be pointer size
 typedef uintptr_t mp_uint_t; // must be pointer size