godot/core/self_list.h
Pedro J. Estébanez 64344e6d1d Fix object leaks caused by unfulfilled yields
Now the stack saved in a `GDScriptFunctionState` is cleared as soon as the `yield()` operation is known not to be resumed because either the script, the instance or both are deleted.

This clears problems like leaked objects by eliminating cases of circular references between `GDScriptFunctionState`s preventing them and the objects they refer to in their saved stacks from being released. As an example, this makes using `SceneTreeTimer` safer.

Furthermore, with this change it's now possible to print early warnings about `yield()`s to released script/instances, as now we know they won't be successfully resumed as the condition for that happens. However, this PR doesn't add such messages, to keep the observed behavior the same for the time being.

Also, now a backup of the function name in `GDScriptFunctionState` is used, since the script may not be valid by the time the function name is needed for the resume-after-yield error messages.
2020-05-05 17:53:47 +02:00

148 lines
4.2 KiB
C++

/*************************************************************************/
/* self_list.h */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2020 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 SELF_LIST_H
#define SELF_LIST_H
#include "core/error_macros.h"
#include "core/typedefs.h"
template <class T>
class SelfList {
public:
class List {
SelfList<T> *_first;
SelfList<T> *_last;
public:
void add(SelfList<T> *p_elem) {
ERR_FAIL_COND(p_elem->_root);
p_elem->_root = this;
p_elem->_next = _first;
p_elem->_prev = NULL;
if (_first) {
_first->_prev = p_elem;
} else {
_last = p_elem;
}
_first = p_elem;
}
void add_last(SelfList<T> *p_elem) {
ERR_FAIL_COND(p_elem->_root);
p_elem->_root = this;
p_elem->_next = NULL;
p_elem->_prev = _last;
if (_last) {
_last->_next = p_elem;
} else {
_first = p_elem;
}
_last = p_elem;
}
void remove(SelfList<T> *p_elem) {
ERR_FAIL_COND(p_elem->_root != this);
if (p_elem->_next) {
p_elem->_next->_prev = p_elem->_prev;
}
if (p_elem->_prev) {
p_elem->_prev->_next = p_elem->_next;
}
if (_first == p_elem) {
_first = p_elem->_next;
}
if (_last == p_elem) {
_last = p_elem->_prev;
}
p_elem->_next = NULL;
p_elem->_prev = NULL;
p_elem->_root = NULL;
}
_FORCE_INLINE_ SelfList<T> *first() { return _first; }
_FORCE_INLINE_ const SelfList<T> *first() const { return _first; }
_FORCE_INLINE_ List() {
_first = NULL;
_last = NULL;
}
_FORCE_INLINE_ ~List() { ERR_FAIL_COND(_first != NULL); }
};
private:
List *_root;
T *_self;
SelfList<T> *_next;
SelfList<T> *_prev;
public:
_FORCE_INLINE_ bool in_list() const { return _root; }
_FORCE_INLINE_ void remove_from_list() {
if (_root) _root->remove(this);
}
_FORCE_INLINE_ SelfList<T> *next() { return _next; }
_FORCE_INLINE_ SelfList<T> *prev() { return _prev; }
_FORCE_INLINE_ const SelfList<T> *next() const { return _next; }
_FORCE_INLINE_ const SelfList<T> *prev() const { return _prev; }
_FORCE_INLINE_ T *self() const { return _self; }
_FORCE_INLINE_ SelfList(T *p_self) {
_self = p_self;
_next = NULL;
_prev = NULL;
_root = NULL;
}
_FORCE_INLINE_ ~SelfList() {
if (_root)
_root->remove(this);
}
};
#endif // SELF_LIST_H