emscripten: Cleanup some wasm32/wasm64 ifdefs.

Fixes #14066.

(cherry picked from commit bb6ced6fc00c018ba418964f69458e222dd08a04)

src/SDL.c

@@ -328,9 +328,21 @@ bool SDL_InitSubSystem(SDL_InitFlags flags)
 
 #ifdef SDL_PLATFORM_EMSCRIPTEN
     MAIN_THREAD_EM_ASM({
+        // make sure this generic table to hang SDL-specific Javascript stuff is available at init time.
         if (typeof(Module['SDL3']) === 'undefined') {
             Module['SDL3'] = {};
         }
+
+        var SDL3 = Module['SDL3'];
+        #if defined(__wasm32__)
+        if (typeof(SDL3.JSVarToCPtr) === 'undefined') { SDL3.JSVarToCPtr = function(v) { return v; }; }
+        if (typeof(SDL3.CPtrToHeap32Index) === 'undefined') { SDL3.CPtrToHeap32Index = function(ptr) { return ptr >>> 2; }; }
+        #elif defined(__wasm64__)
+        if (typeof(SDL3.JSVarToCPtr) === 'undefined') { SDL3.JSVarToCPtr = function(v) { return BigInt(v); }; }
+        if (typeof(SDL3.CPtrToHeap32Index) === 'undefined') { SDL3.CPtrToHeap32Index = function(ptr) { return Number(ptr / 4n); }; }
+        #else
+        #error Please define your platform.
+        #endif
     });
 #endif
 

src/audio/emscripten/SDL_emscriptenaudio.c

@@ -41,13 +41,8 @@ static bool EMSCRIPTENAUDIO_PlayDevice(SDL_AudioDevice *device, const Uint8 *buf
     const int framelen = SDL_AUDIO_FRAMESIZE(device->spec);
     MAIN_THREAD_EM_ASM({
         /* Convert incoming buf pointer to a HEAPF32 offset. */
-        #ifdef __wasm64__
-        var buf = $0 / 4;
-        #else
-        var buf = $0 >>> 2;
-        #endif
-
         var SDL3 = Module['SDL3'];
+        var buf = SDL3.CPtrToHeap32Index($0);
         var numChannels = SDL3.audio_playback.currentPlaybackBuffer['numberOfChannels'];
         for (var c = 0; c < numChannels; ++c) {
             var channelData = SDL3.audio_playback.currentPlaybackBuffer['getChannelData'](c);

src/video/emscripten/SDL_emscriptenevents.c

@@ -974,11 +974,7 @@ static void Emscripten_prep_pointer_event_callbacks(void)
 
                 var ptr = _SDL_malloc($0);
                 if (ptr != 0) {
-                    #ifdef __wasm32__
-                    var idx = ptr >> 2;
-                    #elif __wasm64__
-                    var idx = Number(ptr / 4n);
-                    #endif
+                    var idx = SDL3.CPtrToHeap32Index(ptr);
                     HEAP32[idx++] = ptrtype;
                     HEAP32[idx++] = event.pointerId;
                     HEAP32[idx++] = (typeof(event.button) !== "undefined") ? event.button : -1;
@@ -1016,11 +1012,7 @@ static void Emscripten_set_pointer_event_callbacks(SDL_WindowData *data)
                 var d = SDL3.makePointerEventCStruct(rect.left, rect.top, event);
                 if (d != 0)
                 {
-                    #ifdef  __wasm32__
-                    _Emscripten_HandlePointerEnter(data, d);
-                    #elif __wasm64__
-                    _Emscripten_HandlePointerEnter(BigInt(data), d);
-                    #endif
+                    _Emscripten_HandlePointerEnter(SDL3.JSVarToCPtr(data), d);
                     _SDL_free(d);
                 }
             };
@@ -1029,11 +1021,7 @@ static void Emscripten_set_pointer_event_callbacks(SDL_WindowData *data)
                 var d = SDL3.makePointerEventCStruct(rect.left, rect.top, event);
                 if (d != 0)
                 {
-                    #ifdef __wasm32__
-                        _Emscripten_HandlePointerLeave(data, d);
-                    #elif __wasm64__
-                        _Emscripten_HandlePointerLeave(BigInt(data), d);
-                    #endif
+                    _Emscripten_HandlePointerLeave(SDL3.JSVarToCPtr(data), d);
                     _SDL_free(d);
                 }
             };
@@ -1042,11 +1030,7 @@ static void Emscripten_set_pointer_event_callbacks(SDL_WindowData *data)
                 var d = SDL3.makePointerEventCStruct(rect.left, rect.top, event);
                 if (d != 0)
                 {
-                    #ifdef __wasm32__
-                        _Emscripten_HandlePointerGeneric(data, d);
-                    #elif __wasm64__
-                        _Emscripten_HandlePointerGeneric(BigInt(data), d);
-                    #endif
+                    _Emscripten_HandlePointerGeneric(SDL3.JSVarToCPtr(data), d);
                     _SDL_free(d);
                 }
             };
@@ -1104,11 +1088,7 @@ static void Emscripten_set_global_mouseup_callback(SDL_VideoDevice *device)
                 var d = SDL3.makePointerEventCStruct(0, 0, event);
                 if (d != 0)
                 {
-                    #ifdef __wasm32__
-                    _Emscripten_HandleMouseButtonUpGlobal($0, d);
-                    #elif __wasm64__
-                    _Emscripten_HandleMouseButtonUpGlobal(BigInt($0), d);
-                    #endif
+                    _Emscripten_HandleMouseButtonUpGlobal(SDL3.JSVarToCPtr($0), d);
                     _SDL_free(d);
                 }
             };
@@ -1348,11 +1328,7 @@ void Emscripten_RegisterEventHandlers(SDL_WindowData *data)
                 // don't try to adjust the state on the actual lock key presses; the normal key handler will catch that and adjust.
                 if ((event.key != "CapsLock") && (event.key != "NumLock") && (event.key != "ScrollLock"))
                 {
-                    #ifdef __wasm32__
-                        _Emscripten_HandleLockKeysCheck(data, event.getModifierState("CapsLock"), event.getModifierState("NumLock"), event.getModifierState("ScrollLock"));
-                    #elif __wasm64__
-                        _Emscripten_HandleLockKeysCheck(BigInt(data), event.getModifierState("CapsLock"), event.getModifierState("NumLock"), event.getModifierState("ScrollLock"));
-                    #endif
+                    _Emscripten_HandleLockKeysCheck(Module['SDL3'].JSVarToCPtr(data), event.getModifierState("CapsLock"), event.getModifierState("NumLock"), event.getModifierState("ScrollLock"));
                 }
             };
             document.addEventListener("keydown", document.sdlEventHandlerLockKeysCheck);