[turbine] Cleanup type safety code for application data

src/olympic/turbine/include/turbine/context.hpp

@@ -39,20 +39,57 @@ inline ox::FileSystem *rom(Context &ctx) noexcept {
 
 struct WrapBase {
 	virtual ~WrapBase() = default;
+	virtual WrapBase *copyTo(ox::Span<char> s) noexcept = 0;
+	virtual operator bool() const noexcept = 0;
 };
 
 template<typename T>
 struct Wrap: public WrapBase {
 	T *data{};
+	Wrap(T *pData) noexcept: data(pData) {
+	}
+	WrapBase *copyTo(ox::Span<char> s) noexcept override {
+		oxAssert(s.size() >= sizeof(Wrap), "too small buffer");
+		return new(s.data()) Wrap{data};
+	}
+	operator bool() const noexcept override {
+		return data != nullptr;
+	}
 };
 
-void setApplicationDataRaw(Context &ctx, void *applicationData) noexcept;
+class WrapPtr {
+	private:
+		WrapBase *m_wrapPtr{};
+		ox::Array<char, sizeof(WrapBase) + sizeof(void*)> m_wrapData;
+	public:
+		template<typename T>
+		inline WrapPtr &operator=(T *ptr) noexcept {
+			m_wrapPtr = new(m_wrapData.data()) Wrap(ptr);
+			return *this;
+		}
+		inline WrapPtr &operator=(WrapBase &ptr) noexcept {
+			if (ptr) {
+				m_wrapPtr = ptr.copyTo(m_wrapData);
+			} else {
+				m_wrapPtr = nullptr;
+			}
+			return *this;
+		}
+		inline operator bool() const noexcept {
+			return m_wrapPtr && *m_wrapPtr;
+		}
+		[[nodiscard]]
+		inline WrapBase *getWrapBase() const noexcept {
+			return m_wrapPtr;
+		}
+};
+
+void setApplicationDataRaw(Context &ctx, WrapBase &applicationData) noexcept;
 
 template<typename T>
 void setApplicationData(Context &ctx, T *applicationData) noexcept {
-	Wrap<T> w;
-	w.data = applicationData;
-	setApplicationDataRaw(ctx, &w);
+	Wrap<T> w(applicationData);
+	setApplicationDataRaw(ctx, w);
 }
 
 [[nodiscard]]
@@ -61,13 +98,14 @@ WrapBase *applicationDataRaw(Context &ctx) noexcept;
 template<typename T>
 [[nodiscard]]
 T *applicationData(Context &ctx) noexcept {
+	auto const raw = applicationDataRaw(ctx);
 #ifdef OX_BARE_METAL
-	return static_cast<Wrap<T>*>(applicationDataRaw(ctx))->data;
+	auto const out = static_cast<Wrap<T>*>(raw);
 #else
-	auto const out = dynamic_cast<Wrap<T>*>(applicationDataRaw(ctx));
-	oxAssert(out, "Cast failed - wrong type");
-	return out->data;
+	auto const out = dynamic_cast<Wrap<T>*>(raw);
 #endif
+	oxAssert(out || !raw, "Cast failed - wrong type");
+	return out->data;
 }
 
 void setKeyEventHandler(Context &ctx, KeyEventHandler h) noexcept;

src/olympic/turbine/src/gba/context.cpp

@@ -18,20 +18,12 @@ keel::Context &keelCtx(Context &ctx) noexcept {
 	return ctx.keelCtx;
 }
 
-void setApplicationDataRaw(Context &ctx, void const*applicationData) noexcept {
-	if (applicationData) {
-		ctx.applicationData.emplace();
-		memcpy(&ctx.applicationData.value(), applicationData, sizeof(Wrap<void>));
-	} else {
-		ctx.applicationData.reset();
-	}
+void setApplicationDataRaw(Context &ctx, WrapBase &applicationData) noexcept {
+	ctx.applicationData = applicationData;
 }
 
 WrapBase *applicationDataRaw(Context &ctx) noexcept {
-	if (!ctx.applicationData) {
-		return nullptr;
-	}
-	return std::bit_cast<WrapBase*>(&*ctx.applicationData);
+	return ctx.applicationData.getWrapBase();
 }
 
 }

src/olympic/turbine/src/gba/context.hpp

@@ -17,7 +17,7 @@ class Context {
 		UpdateHandler updateHandler = [](Context&) -> int {return 0;};
 		keel::Context keelCtx;
 		KeyEventHandler keyEventHandler = nullptr;
-		ox::Optional<std::array<char, sizeof(WrapBase) + sizeof(uintptr_t)>> applicationData;
+		WrapPtr applicationData;
 
 		// GBA impl data /////////////////////////////////////////////////////////
 		bool running = true;

src/olympic/turbine/src/glfw/context.cpp

@@ -20,20 +20,12 @@ keel::Context &keelCtx(Context &ctx) noexcept {
 	return ctx.keelCtx;
 }
 
-void setApplicationDataRaw(Context &ctx, void *applicationData) noexcept {
-	if (applicationData) {
-		ctx.applicationData.emplace();
-		memcpy(&ctx.applicationData.value(), applicationData, sizeof(Wrap<void>));
-	} else {
-		ctx.applicationData.reset();
-	}
+void setApplicationDataRaw(Context &ctx, WrapBase &applicationData) noexcept {
+	ctx.applicationData = applicationData;
 }
 
 WrapBase *applicationDataRaw(Context &ctx) noexcept {
-	if (!ctx.applicationData) {
-		return nullptr;
-	}
-	return std::bit_cast<WrapBase*>(&*ctx.applicationData);
+	return ctx.applicationData.getWrapBase();
 }
 
 }

src/olympic/turbine/src/glfw/context.hpp

@@ -16,7 +16,7 @@ class Context {
 		UpdateHandler updateHandler = [](Context&) -> int {return 0;};
 		keel::Context keelCtx;
 		KeyEventHandler keyEventHandler = nullptr;
-		ox::Optional<std::array<char, sizeof(WrapBase) + sizeof(uintptr_t)>> applicationData;
+		WrapPtr applicationData;
 
 		// GLFW impl data ////////////////////////////////////////////////////////
 		int uninterruptedRefreshes = 3;