SDL: N3DS: Refactor joystick module to avoid globals.

SDL Commits
1 
From 86a8714feab1a93be67da1eae8a406f9e158bf0f Mon Sep 17 00:00:00 2001
From: Pierre Wendling <[EMAIL REDACTED]>
Date: Tue, 20 Sep 2022 23:04:20 -0400
Subject: [PATCH] N3DS: Refactor joystick module to avoid globals.

---
 src/joystick/n3ds/SDL_sysjoystick.c | 114 +++++++++++++++-------------
 1 file changed, 62 insertions(+), 52 deletions(-)

diff --git a/src/joystick/n3ds/SDL_sysjoystick.c b/src/joystick/n3ds/SDL_sysjoystick.c
index 1b98462adcac..6525d51003e7 100644
--- a/src/joystick/n3ds/SDL_sysjoystick.c
+++ b/src/joystick/n3ds/SDL_sysjoystick.c
@@ -45,18 +45,10 @@
 */
 #define CORRECTION_FACTOR_Y -CORRECTION_FACTOR_X
 
-typedef struct N3DSJoystickState
-{
-    u32 kDown;
-    u32 kUp;
-    circlePosition circlePos;
-    circlePosition cStickPos;
-} N3DSJoystickState;
-
-SDL_FORCE_INLINE void UpdateAxis(SDL_Joystick *joystick, N3DSJoystickState *previous_state);
-SDL_FORCE_INLINE void UpdateButtons(SDL_Joystick *joystick, N3DSJoystickState *previous_state);
-
-static N3DSJoystickState current_state;
+SDL_FORCE_INLINE void UpdateN3DSPressedButtons(SDL_Joystick *joystick);
+SDL_FORCE_INLINE void UpdateN3DSReleasedButtons(SDL_Joystick *joystick);
+SDL_FORCE_INLINE void UpdateN3DSCircle(SDL_Joystick *joystick);
+SDL_FORCE_INLINE void UpdateN3DSCStick(SDL_Joystick *joystick);
 
 static int
 N3DS_JoystickInit(void)
@@ -110,64 +102,82 @@ N3DS_JoystickSetSensorsEnabled(SDL_Joystick *joystick, SDL_bool enabled)
 static void
 N3DS_JoystickUpdate(SDL_Joystick *joystick)
 {
-    N3DSJoystickState previous_state = current_state;
+    UpdateN3DSPressedButtons(joystick);
+    UpdateN3DSReleasedButtons(joystick);
+    UpdateN3DSCircle(joystick);
+    UpdateN3DSCStick(joystick);
+}
+
+SDL_FORCE_INLINE void
+UpdateN3DSPressedButtons(SDL_Joystick *joystick)
+{
+    static u32 previous_state = 0;
+    u32 updated_down;
+    u32 current_state = hidKeysDown();
+    updated_down = previous_state ^ current_state;
+    if (updated_down) {
+        for (Uint8 i = 0; i < joystick->nbuttons; i++) {
+            if (current_state & BIT(i) & updated_down) {
+                SDL_PrivateJoystickButton(joystick, i, SDL_PRESSED);
+            }
+        }
+    }
+    previous_state = current_state;
+}
 
-    UpdateAxis(joystick, &previous_state);
-    UpdateButtons(joystick, &previous_state);
+SDL_FORCE_INLINE void
+UpdateN3DSReleasedButtons(SDL_Joystick *joystick)
+{
+    static u32 previous_state = 0;
+    u32 updated_up;
+    u32 current_state = hidKeysUp();
+    updated_up = previous_state ^ current_state;
+    if (updated_up) {
+        for (Uint8 i = 0; i < joystick->nbuttons; i++) {
+            if (current_state & BIT(i) & updated_up) {
+                SDL_PrivateJoystickButton(joystick, i, SDL_RELEASED);
+            }
+        }
+    }
+    previous_state = current_state;
 }
 
 SDL_FORCE_INLINE void
-UpdateAxis(SDL_Joystick *joystick, N3DSJoystickState *previous_state)
+UpdateN3DSCircle(SDL_Joystick *joystick)
 {
-    hidCircleRead(&current_state.circlePos);
-    if (previous_state->circlePos.dx != current_state.circlePos.dx) {
+    static circlePosition previous_state = { 0, 0 };
+    circlePosition current_state;
+    hidCircleRead(&current_state);
+    if (previous_state.dx != current_state.dx) {
         SDL_PrivateJoystickAxis(joystick,
                                 0,
-                                current_state.circlePos.dx * CORRECTION_FACTOR_X);
+                                current_state.dx * CORRECTION_FACTOR_X);
     }
-    if (previous_state->circlePos.dy != current_state.circlePos.dy) {
+    if (previous_state.dy != current_state.dy) {
         SDL_PrivateJoystickAxis(joystick,
                                 1,
-                                current_state.circlePos.dy * CORRECTION_FACTOR_Y);
+                                current_state.dy * CORRECTION_FACTOR_Y);
     }
+    previous_state = current_state;
+}
 
-    hidCstickRead(&current_state.cStickPos);
-    if (previous_state->cStickPos.dx != current_state.cStickPos.dx) {
+SDL_FORCE_INLINE void
+UpdateN3DSCStick(SDL_Joystick *joystick)
+{
+    static circlePosition previous_state = { 0, 0 };
+    circlePosition current_state;
+    hidCstickRead(&current_state);
+    if (previous_state.dx != current_state.dx) {
         SDL_PrivateJoystickAxis(joystick,
                                 2,
-                                current_state.cStickPos.dx * CORRECTION_FACTOR_X);
+                                current_state.dx * CORRECTION_FACTOR_X);
     }
-    if (previous_state->cStickPos.dy != current_state.cStickPos.dy) {
+    if (previous_state.dy != current_state.dy) {
         SDL_PrivateJoystickAxis(joystick,
                                 3,
-                                current_state.cStickPos.dy * CORRECTION_FACTOR_Y);
-    }
-}
-
-SDL_FORCE_INLINE void
-UpdateButtons(SDL_Joystick *joystick, N3DSJoystickState *previous_state)
-{
-    u32 updated_down, updated_up;
-
-    current_state.kDown = hidKeysDown();
-    updated_down = previous_state->kDown ^ current_state.kDown;
-    if (updated_down) {
-        for (Uint8 i = 0; i < joystick->nbuttons; i++) {
-            if (current_state.kDown & BIT(i) & updated_down) {
-                SDL_PrivateJoystickButton(joystick, i, SDL_PRESSED);
-            }
-        }
-    }
-
-    current_state.kUp = hidKeysUp();
-    updated_up = previous_state->kUp ^ current_state.kUp;
-    if (updated_up) {
-        for (Uint8 i = 0; i < joystick->nbuttons; i++) {
-            if (current_state.kUp & BIT(i) & updated_up) {
-                SDL_PrivateJoystickButton(joystick, i, SDL_RELEASED);
-            }
-        }
+                                current_state.dy * CORRECTION_FACTOR_Y);
     }
+    previous_state = current_state;
 }
 
 static void