godot/core/ordered_hash_map.h
Rémi Verschelde a7f49ac9a1 Update copyright statements to 2020
Happy new year to the wonderful Godot community!

We're starting a new decade with a well-established, non-profit, free
and open source game engine, and tons of further improvements in the
pipeline from hundreds of contributors.

Godot will keep getting better, and we're looking forward to all the
games that the community will keep developing and releasing with it.
2020-01-01 11:16:22 +01:00

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8.5 KiB
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/*************************************************************************/
/* ordered_hash_map.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 ORDERED_HASH_MAP_H
#define ORDERED_HASH_MAP_H
#include "core/hash_map.h"
#include "core/list.h"
#include "core/pair.h"
/**
* A hash map which allows to iterate elements in insertion order.
* Insertion, lookup, deletion have O(1) complexity.
* The API aims to be consistent with Map rather than HashMap, because the
* former is more frequently used and is more coherent with the rest of the
* codebase.
* Deletion during iteration is safe and will preserve the order.
*/
template <class K, class V, class Hasher = HashMapHasherDefault, class Comparator = HashMapComparatorDefault<K>, uint8_t MIN_HASH_TABLE_POWER = 3, uint8_t RELATIONSHIP = 8>
class OrderedHashMap {
typedef List<Pair<const K *, V> > InternalList;
typedef HashMap<K, typename InternalList::Element *, Hasher, Comparator, MIN_HASH_TABLE_POWER, RELATIONSHIP> InternalMap;
InternalList list;
InternalMap map;
public:
class Element {
friend class OrderedHashMap<K, V, Hasher, Comparator, MIN_HASH_TABLE_POWER, RELATIONSHIP>;
typename InternalList::Element *list_element;
typename InternalList::Element *prev_element;
typename InternalList::Element *next_element;
Element(typename InternalList::Element *p_element) {
list_element = p_element;
if (list_element) {
next_element = list_element->next();
prev_element = list_element->prev();
}
}
public:
_FORCE_INLINE_ Element() :
list_element(NULL),
prev_element(NULL),
next_element(NULL) {
}
Element next() const {
return Element(next_element);
}
Element prev() const {
return Element(prev_element);
}
Element(const Element &other) :
list_element(other.list_element),
prev_element(other.prev_element),
next_element(other.next_element) {
}
Element &operator=(const Element &other) {
list_element = other.list_element;
next_element = other.next_element;
prev_element = other.prev_element;
return *this;
}
_FORCE_INLINE_ bool operator==(const Element &p_other) const {
return this->list_element == p_other.list_element;
}
_FORCE_INLINE_ bool operator!=(const Element &p_other) const {
return this->list_element != p_other.list_element;
}
operator bool() const {
return (list_element != NULL);
}
const K &key() const {
CRASH_COND(!list_element);
return *(list_element->get().first);
};
V &value() {
CRASH_COND(!list_element);
return list_element->get().second;
};
const V &value() const {
CRASH_COND(!list_element);
return list_element->get().second;
};
V &get() {
CRASH_COND(!list_element);
return list_element->get().second;
};
const V &get() const {
CRASH_COND(!list_element);
return list_element->get().second;
};
};
class ConstElement {
friend class OrderedHashMap<K, V, Hasher, Comparator, MIN_HASH_TABLE_POWER, RELATIONSHIP>;
const typename InternalList::Element *list_element;
ConstElement(const typename InternalList::Element *p_element) :
list_element(p_element) {
}
public:
_FORCE_INLINE_ ConstElement() :
list_element(NULL) {
}
ConstElement(const ConstElement &other) :
list_element(other.list_element) {
}
ConstElement &operator=(const ConstElement &other) {
list_element = other.list_element;
return *this;
}
ConstElement next() const {
return ConstElement(list_element ? list_element->next() : NULL);
}
ConstElement prev() const {
return ConstElement(list_element ? list_element->prev() : NULL);
}
_FORCE_INLINE_ bool operator==(const ConstElement &p_other) const {
return this->list_element == p_other.list_element;
}
_FORCE_INLINE_ bool operator!=(const ConstElement &p_other) const {
return this->list_element != p_other.list_element;
}
operator bool() const {
return (list_element != NULL);
}
const K &key() const {
CRASH_COND(!list_element);
return *(list_element->get().first);
};
const V &value() const {
CRASH_COND(!list_element);
return list_element->get().second;
};
const V &get() const {
CRASH_COND(!list_element);
return list_element->get().second;
};
};
ConstElement find(const K &p_key) const {
typename InternalList::Element *const *list_element = map.getptr(p_key);
if (list_element) {
return ConstElement(*list_element);
}
return ConstElement(NULL);
}
Element find(const K &p_key) {
typename InternalList::Element **list_element = map.getptr(p_key);
if (list_element) {
return Element(*list_element);
}
return Element(NULL);
}
Element insert(const K &p_key, const V &p_value) {
typename InternalList::Element **list_element = map.getptr(p_key);
if (list_element) {
(*list_element)->get().second = p_value;
return Element(*list_element);
}
typename InternalList::Element *new_element = list.push_back(Pair<const K *, V>(NULL, p_value));
typename InternalMap::Element *e = map.set(p_key, new_element);
new_element->get().first = &e->key();
return Element(new_element);
}
void erase(Element &p_element) {
map.erase(p_element.key());
list.erase(p_element.list_element);
p_element.list_element = NULL;
}
bool erase(const K &p_key) {
typename InternalList::Element **list_element = map.getptr(p_key);
if (list_element) {
list.erase(*list_element);
map.erase(p_key);
return true;
}
return false;
}
inline bool has(const K &p_key) const {
return map.has(p_key);
}
const V &operator[](const K &p_key) const {
ConstElement e = find(p_key);
CRASH_COND(!e);
return e.value();
}
V &operator[](const K &p_key) {
Element e = find(p_key);
if (!e) {
// consistent with Map behaviour
e = insert(p_key, V());
}
return e.value();
}
inline Element front() {
return Element(list.front());
}
inline Element back() {
return Element(list.back());
}
inline ConstElement front() const {
return ConstElement(list.front());
}
inline ConstElement back() const {
return ConstElement(list.back());
}
inline bool empty() const { return list.empty(); }
inline int size() const { return list.size(); }
const void *id() const {
return list.id();
}
void clear() {
map.clear();
list.clear();
}
private:
void _copy_from(const OrderedHashMap &p_map) {
for (ConstElement E = p_map.front(); E; E = E.next()) {
insert(E.key(), E.value());
}
}
public:
void operator=(const OrderedHashMap &p_map) {
_copy_from(p_map);
}
OrderedHashMap(const OrderedHashMap &p_map) {
_copy_from(p_map);
}
_FORCE_INLINE_ OrderedHashMap() {
}
};
#endif // ORDERED_HASH_MAP_H