text: /*************************************************************************/
  /*  reference.cpp                                                        */
  /*************************************************************************/
  /*                       This file is part of:                           */
  /*                           GODOT ENGINE                                */
  /*                      https://godotengine.org                          */
  /*************************************************************************/
  /* Copyright (c) 2007-2019 Juan Linietsky, Ariel Manzur.                 */
  /* Copyright (c) 2014-2019 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.                */
  /*************************************************************************/
  #include "reference.h"
  #include "script_language.h"
  
  bool Reference::init_ref() {
  
  	if (refcount.ref()) {
  
  		// this may fail in the scenario of two threads assigning the pointer for the FIRST TIME
  		// at the same time, which is never likely to happen (would be crazy to do)
  		// so don't do it.
  
  		if (refcount_init.get() > 0) {
  			refcount_init.unref();
  			refcount.unref(); // first referencing is already 1, so compensate for the ref above
  		}
  
  		return true;
  	} else {
  
  		return false;
  	}
  }
  
  void Reference::_bind_methods() {
  
  	ObjectTypeDB::bind_method(_MD("init_ref"), &Reference::init_ref);
  	ObjectTypeDB::bind_method(_MD("reference"), &Reference::reference);
  	ObjectTypeDB::bind_method(_MD("unreference"), &Reference::unreference);
  }
  
  int Reference::reference_get_count() const {
  	return refcount.get();
  }
  
  void Reference::reference() {
  
  	refcount.ref();
  	if (get_script_instance()) {
  		get_script_instance()->refcount_incremented();
  	}
  }
  bool Reference::unreference() {
  
  	bool die = refcount.unref();
  
  	if (get_script_instance()) {
  		die = die && get_script_instance()->refcount_decremented();
  	}
  
  	return die;
  }
  
  Reference::Reference() {
  
  	refcount.init();
  	refcount_init.init();
  }
  
  Reference::~Reference() {
  }
  
  Variant WeakRef::get_ref() const {
  
  	if (ref == 0)
  		return Variant();
  
  	Object *obj = ObjectDB::get_instance(ref);
  	if (!obj)
  		return Variant();
  	Reference *r = obj->cast_to<Reference>();
  	if (r) {
  
  		return REF(r);
  	}
  
  	return obj;
  }
  
  void WeakRef::set_obj(Object *p_object) {
  	ref = p_object ? p_object->get_instance_ID() : 0;
  }
  
  void WeakRef::set_ref(const REF &p_ref) {
  
  	ref = p_ref.is_valid() ? p_ref->get_instance_ID() : 0;
  }
  
  WeakRef::WeakRef() {
  	ref = 0;
  }
  
  void WeakRef::_bind_methods() {
  
  	ObjectTypeDB::bind_method(_MD("get_ref:Object"), &WeakRef::get_ref);
  }
  #if 0
  
  Reference * RefBase::get_reference_from_ref(const RefBase &p_base) {
  
  	return p_base.get_reference();
  }
  void RefBase::ref_inc(Reference *p_reference) {
  
  	p_reference->refcount.ref();
  }
  bool RefBase::ref_dec(Reference *p_reference) {
  
  	bool ref = p_reference->refcount.unref();
  	return ref;
  }
  
  Reference *RefBase::first_ref(Reference *p_reference) {
  
  	if (p_reference->refcount.ref()) {
  
  		// this may fail in the scenario of two threads assigning the pointer for the FIRST TIME
  		// at the same time, which is never likely to happen (would be crazy to do)
  		// so don't do it.
  
  		if (p_reference->refcount_init.get()>0) {
  			p_reference->refcount_init.unref();
  			p_reference->refcount.unref(); // first referencing is already 1, so compensate for the ref above
  		}
  
  		return p_reference;
  	} else {
  
  		return 0;
  	}
  
  }
  char * RefBase::get_refptr_data(const RefPtr &p_refptr) const {
  
  	return p_refptr.data;
  }
  #endif
  