From 5dfefb477a18aaeb1c0ea3fafc5bc68238b3e4d6 Mon Sep 17 00:00:00 2001
From: Romain Goyet <romain.goyet@numworks.com>
Date: Thu, 8 Nov 2018 13:29:49 +0100
Subject: [PATCH] [python] Rename micropython_port_should_interrupt to
 micropython_port_vm_hook_loop

---
 build/toolchain.emscripten.mak |  2 +-
 python/port/helpers.cpp        | 14 +++++++++++---
 python/port/helpers.h          |  4 +---
 python/port/mpconfigport.h     |  2 +-
 4 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/build/toolchain.emscripten.mak b/build/toolchain.emscripten.mak
index baabdca9b..7048b6d02 100644
--- a/build/toolchain.emscripten.mak
+++ b/build/toolchain.emscripten.mak
@@ -63,7 +63,7 @@ _do_load_from_lexer \
 _fun_bc_call \
 _fun_builtin_var_call \
 _main \
-_micropython_port_should_interrupt \
+_micropython_port_vm_hook_loop \
 _mp_builtin___import__ \
 _mp_builtin_input \
 _mp_call_function_0 \
diff --git a/python/port/helpers.cpp b/python/port/helpers.cpp
index cda2b53ca..ac0114b02 100644
--- a/python/port/helpers.cpp
+++ b/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();
   }
 }
diff --git a/python/port/helpers.h b/python/port/helpers.h
index b07c6de29..375256909 100644
--- a/python/port/helpers.h
+++ b/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
 }
diff --git a/python/port/mpconfigport.h b/python/port/mpconfigport.h
index 17794886b..109a0682c 100644
--- a/python/port/mpconfigport.h
+++ b/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