Merge pull request #49312 from RandomShaper/reference_to_ref_count

Rename `Reference` to `RefCounted`

1 files changed, 297 insertions, 0 deletions

diff --git a/core/object/ref_counted.h b/core/object/ref_counted.h
new file mode 100644
index 0000000000..3dd7cc456b
--- /dev/null
+++ b/core/object/ref_counted.h
@@ -0,0 +1,297 @@
+/*************************************************************************/
+/*  ref_counted.h                                                        */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef REF_COUNTED_H
+#define REF_COUNTED_H
+
+#include "core/object/class_db.h"
+#include "core/templates/safe_refcount.h"
+
+class RefCounted : public Object {
+	GDCLASS(RefCounted, Object);
+	SafeRefCount refcount;
+	SafeRefCount refcount_init;
+
+protected:
+	static void _bind_methods();
+
+public:
+	_FORCE_INLINE_ bool is_referenced() const { return refcount_init.get() != 1; }
+	bool init_ref();
+	bool reference(); // returns false if refcount is at zero and didn't get increased
+	bool unreference();
+	int reference_get_count() const;
+
+	RefCounted();
+	~RefCounted() {}
+};
+
+template <class T>
+class Ref {
+	T *reference = nullptr;
+
+	void ref(const Ref &p_from) {
+		if (p_from.reference == reference) {
+			return;
+		}
+
+		unref();
+
+		reference = p_from.reference;
+		if (reference) {
+			reference->reference();
+		}
+	}
+
+	void ref_pointer(T *p_ref) {
+		ERR_FAIL_COND(!p_ref);
+
+		if (p_ref->init_ref()) {
+			reference = p_ref;
+		}
+	}
+
+	//virtual RefCounted * get_reference() const { return reference; }
+public:
+	_FORCE_INLINE_ bool operator==(const T *p_ptr) const {
+		return reference == p_ptr;
+	}
+	_FORCE_INLINE_ bool operator!=(const T *p_ptr) const {
+		return reference != p_ptr;
+	}
+
+	_FORCE_INLINE_ bool operator<(const Ref<T> &p_r) const {
+		return reference < p_r.reference;
+	}
+	_FORCE_INLINE_ bool operator==(const Ref<T> &p_r) const {
+		return reference == p_r.reference;
+	}
+	_FORCE_INLINE_ bool operator!=(const Ref<T> &p_r) const {
+		return reference != p_r.reference;
+	}
+
+	_FORCE_INLINE_ T *operator->() {
+		return reference;
+	}
+
+	_FORCE_INLINE_ T *operator*() {
+		return reference;
+	}
+
+	_FORCE_INLINE_ const T *operator->() const {
+		return reference;
+	}
+
+	_FORCE_INLINE_ const T *ptr() const {
+		return reference;
+	}
+	_FORCE_INLINE_ T *ptr() {
+		return reference;
+	}
+
+	_FORCE_INLINE_ const T *operator*() const {
+		return reference;
+	}
+
+	operator Variant() const {
+		return Variant(reference);
+	}
+
+	void operator=(const Ref &p_from) {
+		ref(p_from);
+	}
+
+	template <class T_Other>
+	void operator=(const Ref<T_Other> &p_from) {
+		RefCounted *refb = const_cast<RefCounted *>(static_cast<const RefCounted *>(p_from.ptr()));
+		if (!refb) {
+			unref();
+			return;
+		}
+		Ref r;
+		r.reference = Object::cast_to<T>(refb);
+		ref(r);
+		r.reference = nullptr;
+	}
+
+	void operator=(const Variant &p_variant) {
+		Object *object = p_variant.get_validated_object();
+
+		if (object == reference) {
+			return;
+		}
+
+		unref();
+
+		if (!object) {
+			return;
+		}
+
+		T *r = Object::cast_to<T>(object);
+		if (r && r->reference()) {
+			reference = r;
+		}
+	}
+
+	template <class T_Other>
+	void reference_ptr(T_Other *p_ptr) {
+		if (reference == p_ptr) {
+			return;
+		}
+		unref();
+
+		T *r = Object::cast_to<T>(p_ptr);
+		if (r) {
+			ref_pointer(r);
+		}
+	}
+
+	Ref(const Ref &p_from) {
+		ref(p_from);
+	}
+
+	template <class T_Other>
+	Ref(const Ref<T_Other> &p_from) {
+		RefCounted *refb = const_cast<RefCounted *>(static_cast<const RefCounted *>(p_from.ptr()));
+		if (!refb) {
+			unref();
+			return;
+		}
+		Ref r;
+		r.reference = Object::cast_to<T>(refb);
+		ref(r);
+		r.reference = nullptr;
+	}
+
+	Ref(T *p_reference) {
+		if (p_reference) {
+			ref_pointer(p_reference);
+		}
+	}
+
+	Ref(const Variant &p_variant) {
+		Object *object = p_variant.get_validated_object();
+
+		if (!object) {
+			return;
+		}
+
+		T *r = Object::cast_to<T>(object);
+		if (r && r->reference()) {
+			reference = r;
+		}
+	}
+
+	inline bool is_valid() const { return reference != nullptr; }
+	inline bool is_null() const { return reference == nullptr; }
+
+	void unref() {
+		//TODO this should be moved to mutexes, since this engine does not really
+		// do a lot of referencing on references and stuff
+		// mutexes will avoid more crashes?
+
+		if (reference && reference->unreference()) {
+			memdelete(reference);
+		}
+		reference = nullptr;
+	}
+
+	void instance() {
+		ref(memnew(T));
+	}
+
+	Ref() {}
+
+	~Ref() {
+		unref();
+	}
+};
+
+typedef Ref<RefCounted> REF;
+
+class WeakRef : public RefCounted {
+	GDCLASS(WeakRef, RefCounted);
+
+	ObjectID ref;
+
+protected:
+	static void _bind_methods();
+
+public:
+	Variant get_ref() const;
+	void set_obj(Object *p_object);
+	void set_ref(const REF &p_ref);
+
+	WeakRef() {}
+};
+
+template <class T>
+struct PtrToArg<Ref<T>> {
+	_FORCE_INLINE_ static Ref<T> convert(const void *p_ptr) {
+		return Ref<T>(const_cast<T *>(reinterpret_cast<const T *>(p_ptr)));
+	}
+
+	_FORCE_INLINE_ static void encode(Ref<T> p_val, const void *p_ptr) {
+		*(Ref<RefCounted> *)p_ptr = p_val;
+	}
+};
+
+template <class T>
+struct PtrToArg<const Ref<T> &> {
+	_FORCE_INLINE_ static Ref<T> convert(const void *p_ptr) {
+		return Ref<T>((T *)p_ptr);
+	}
+};
+
+#ifdef DEBUG_METHODS_ENABLED
+
+template <class T>
+struct GetTypeInfo<Ref<T>> {
+	static const Variant::Type VARIANT_TYPE = Variant::OBJECT;
+	static const GodotTypeInfo::Metadata METADATA = GodotTypeInfo::METADATA_NONE;
+
+	static inline PropertyInfo get_class_info() {
+		return PropertyInfo(Variant::OBJECT, String(), PROPERTY_HINT_RESOURCE_TYPE, T::get_class_static());
+	}
+};
+
+template <class T>
+struct GetTypeInfo<const Ref<T> &> {
+	static const Variant::Type VARIANT_TYPE = Variant::OBJECT;
+	static const GodotTypeInfo::Metadata METADATA = GodotTypeInfo::METADATA_NONE;
+
+	static inline PropertyInfo get_class_info() {
+		return PropertyInfo(Variant::OBJECT, String(), PROPERTY_HINT_RESOURCE_TYPE, T::get_class_static());
+	}
+};
+
+#endif // DEBUG_METHODS_ENABLED
+
+#endif // REF_COUNTED_H