godot/core/variant/dictionary.cpp
reduz 141c375581 Clean up Hash Functions
Clean up and do fixes to hash functions and newly introduced murmur3 hashes in #61934
* Clean up usage of murmur3
* Fixed usages of binary murmur3 on floats (this is invalid)
* Changed DJB2 to use xor (which seems to be better)
2022-06-20 12:54:19 +02:00

434 lines
12 KiB
C++

/*************************************************************************/
/* dictionary.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2022 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 "dictionary.h"
#include "core/templates/hash_map.h"
#include "core/templates/safe_refcount.h"
#include "core/variant/variant.h"
// required in this order by VariantInternal, do not remove this comment.
#include "core/object/class_db.h"
#include "core/object/object.h"
#include "core/variant/type_info.h"
#include "core/variant/variant_internal.h"
struct DictionaryPrivate {
SafeRefCount refcount;
Variant *read_only = nullptr; // If enabled, a pointer is used to a temporary value that is used to return read-only values.
HashMap<Variant, Variant, VariantHasher, VariantComparator> variant_map;
};
void Dictionary::get_key_list(List<Variant> *p_keys) const {
if (_p->variant_map.is_empty()) {
return;
}
for (const KeyValue<Variant, Variant> &E : _p->variant_map) {
p_keys->push_back(E.key);
}
}
Variant Dictionary::get_key_at_index(int p_index) const {
int index = 0;
for (const KeyValue<Variant, Variant> &E : _p->variant_map) {
if (index == p_index) {
return E.key;
}
index++;
}
return Variant();
}
Variant Dictionary::get_value_at_index(int p_index) const {
int index = 0;
for (const KeyValue<Variant, Variant> &E : _p->variant_map) {
if (index == p_index) {
return E.value;
}
index++;
}
return Variant();
}
Variant &Dictionary::operator[](const Variant &p_key) {
if (unlikely(_p->read_only)) {
if (p_key.get_type() == Variant::STRING_NAME) {
const StringName *sn = VariantInternal::get_string_name(&p_key);
*_p->read_only = _p->variant_map[sn->operator String()];
} else {
*_p->read_only = _p->variant_map[p_key];
}
return *_p->read_only;
} else {
if (p_key.get_type() == Variant::STRING_NAME) {
const StringName *sn = VariantInternal::get_string_name(&p_key);
return _p->variant_map[sn->operator String()];
} else {
return _p->variant_map[p_key];
}
}
}
const Variant &Dictionary::operator[](const Variant &p_key) const {
if (p_key.get_type() == Variant::STRING_NAME) {
const StringName *sn = VariantInternal::get_string_name(&p_key);
return _p->variant_map[sn->operator String()];
} else {
return _p->variant_map[p_key];
}
}
const Variant *Dictionary::getptr(const Variant &p_key) const {
HashMap<Variant, Variant, VariantHasher, VariantComparator>::ConstIterator E;
if (p_key.get_type() == Variant::STRING_NAME) {
const StringName *sn = VariantInternal::get_string_name(&p_key);
E = ((const HashMap<Variant, Variant, VariantHasher, VariantComparator> *)&_p->variant_map)->find(sn->operator String());
} else {
E = ((const HashMap<Variant, Variant, VariantHasher, VariantComparator> *)&_p->variant_map)->find(p_key);
}
if (!E) {
return nullptr;
}
return &E->value;
}
Variant *Dictionary::getptr(const Variant &p_key) {
HashMap<Variant, Variant, VariantHasher, VariantComparator>::Iterator E;
if (p_key.get_type() == Variant::STRING_NAME) {
const StringName *sn = VariantInternal::get_string_name(&p_key);
E = ((HashMap<Variant, Variant, VariantHasher, VariantComparator> *)&_p->variant_map)->find(sn->operator String());
} else {
E = ((HashMap<Variant, Variant, VariantHasher, VariantComparator> *)&_p->variant_map)->find(p_key);
}
if (!E) {
return nullptr;
}
if (unlikely(_p->read_only != nullptr)) {
*_p->read_only = E->value;
return _p->read_only;
} else {
return &E->value;
}
}
Variant Dictionary::get_valid(const Variant &p_key) const {
HashMap<Variant, Variant, VariantHasher, VariantComparator>::ConstIterator E;
if (p_key.get_type() == Variant::STRING_NAME) {
const StringName *sn = VariantInternal::get_string_name(&p_key);
E = ((const HashMap<Variant, Variant, VariantHasher, VariantComparator> *)&_p->variant_map)->find(sn->operator String());
} else {
E = ((const HashMap<Variant, Variant, VariantHasher, VariantComparator> *)&_p->variant_map)->find(p_key);
}
if (!E) {
return Variant();
}
return E->value;
}
Variant Dictionary::get(const Variant &p_key, const Variant &p_default) const {
const Variant *result = getptr(p_key);
if (!result) {
return p_default;
}
return *result;
}
int Dictionary::size() const {
return _p->variant_map.size();
}
bool Dictionary::is_empty() const {
return !_p->variant_map.size();
}
bool Dictionary::has(const Variant &p_key) const {
if (p_key.get_type() == Variant::STRING_NAME) {
const StringName *sn = VariantInternal::get_string_name(&p_key);
return _p->variant_map.has(sn->operator String());
} else {
return _p->variant_map.has(p_key);
}
}
bool Dictionary::has_all(const Array &p_keys) const {
for (int i = 0; i < p_keys.size(); i++) {
if (!has(p_keys[i])) {
return false;
}
}
return true;
}
bool Dictionary::erase(const Variant &p_key) {
ERR_FAIL_COND_V_MSG(_p->read_only, false, "Dictionary is in read-only state.");
if (p_key.get_type() == Variant::STRING_NAME) {
const StringName *sn = VariantInternal::get_string_name(&p_key);
return _p->variant_map.erase(sn->operator String());
} else {
return _p->variant_map.erase(p_key);
}
}
bool Dictionary::operator==(const Dictionary &p_dictionary) const {
return recursive_equal(p_dictionary, 0);
}
bool Dictionary::operator!=(const Dictionary &p_dictionary) const {
return !recursive_equal(p_dictionary, 0);
}
bool Dictionary::recursive_equal(const Dictionary &p_dictionary, int recursion_count) const {
// Cheap checks
if (_p == p_dictionary._p) {
return true;
}
if (_p->variant_map.size() != p_dictionary._p->variant_map.size()) {
return false;
}
// Heavy O(n) check
if (recursion_count > MAX_RECURSION) {
ERR_PRINT("Max recursion reached");
return true;
}
recursion_count++;
for (const KeyValue<Variant, Variant> &this_E : _p->variant_map) {
HashMap<Variant, Variant, VariantHasher, VariantComparator>::ConstIterator other_E = ((const HashMap<Variant, Variant, VariantHasher, VariantComparator> *)&p_dictionary._p->variant_map)->find(this_E.key);
if (!other_E || !this_E.value.hash_compare(other_E->value, recursion_count)) {
return false;
}
}
return true;
}
void Dictionary::_ref(const Dictionary &p_from) const {
if (unlikely(p_from._p->read_only != nullptr)) {
// If p_from is a read-only dictionary, just copy the contents to avoid further modification.
if (_p) {
_unref();
}
_p = memnew(DictionaryPrivate);
_p->refcount.init();
_p->variant_map = p_from._p->variant_map;
return;
}
//make a copy first (thread safe)
if (!p_from._p->refcount.ref()) {
return; // couldn't copy
}
//if this is the same, unreference the other one
if (p_from._p == _p) {
_p->refcount.unref();
return;
}
if (_p) {
_unref();
}
_p = p_from._p;
}
void Dictionary::clear() {
ERR_FAIL_COND_MSG(_p->read_only, "Dictionary is in read-only state.");
_p->variant_map.clear();
}
void Dictionary::merge(const Dictionary &p_dictionary, bool p_overwrite) {
for (const KeyValue<Variant, Variant> &E : p_dictionary._p->variant_map) {
if (p_overwrite || !has(E.key)) {
this->operator[](E.key) = E.value;
}
}
}
void Dictionary::_unref() const {
ERR_FAIL_COND(!_p);
if (_p->refcount.unref()) {
if (_p->read_only) {
memdelete(_p->read_only);
}
memdelete(_p);
}
_p = nullptr;
}
uint32_t Dictionary::hash() const {
return recursive_hash(0);
}
uint32_t Dictionary::recursive_hash(int recursion_count) const {
if (recursion_count > MAX_RECURSION) {
ERR_PRINT("Max recursion reached");
return 0;
}
uint32_t h = hash_murmur3_one_32(Variant::DICTIONARY);
recursion_count++;
for (const KeyValue<Variant, Variant> &E : _p->variant_map) {
h = hash_murmur3_one_32(E.key.recursive_hash(recursion_count), h);
h = hash_murmur3_one_32(E.value.recursive_hash(recursion_count), h);
}
return hash_fmix32(h);
}
Array Dictionary::keys() const {
Array varr;
if (_p->variant_map.is_empty()) {
return varr;
}
varr.resize(size());
int i = 0;
for (const KeyValue<Variant, Variant> &E : _p->variant_map) {
varr[i] = E.key;
i++;
}
return varr;
}
Array Dictionary::values() const {
Array varr;
if (_p->variant_map.is_empty()) {
return varr;
}
varr.resize(size());
int i = 0;
for (const KeyValue<Variant, Variant> &E : _p->variant_map) {
varr[i] = E.value;
i++;
}
return varr;
}
const Variant *Dictionary::next(const Variant *p_key) const {
if (p_key == nullptr) {
// caller wants to get the first element
if (_p->variant_map.begin()) {
return &_p->variant_map.begin()->key;
}
return nullptr;
}
HashMap<Variant, Variant, VariantHasher, VariantComparator>::Iterator E = _p->variant_map.find(*p_key);
if (!E) {
return nullptr;
}
++E;
if (E) {
return &E->key;
}
return nullptr;
}
Dictionary Dictionary::duplicate(bool p_deep) const {
return recursive_duplicate(p_deep, 0);
}
void Dictionary::set_read_only(bool p_enable) {
if (p_enable == bool(_p->read_only != nullptr)) {
return;
}
if (p_enable) {
_p->read_only = memnew(Variant);
} else {
memdelete(_p->read_only);
_p->read_only = nullptr;
}
}
bool Dictionary::is_read_only() const {
return _p->read_only != nullptr;
}
Dictionary Dictionary::recursive_duplicate(bool p_deep, int recursion_count) const {
Dictionary n;
if (recursion_count > MAX_RECURSION) {
ERR_PRINT("Max recursion reached");
return n;
}
if (p_deep) {
recursion_count++;
for (const KeyValue<Variant, Variant> &E : _p->variant_map) {
n[E.key.recursive_duplicate(true, recursion_count)] = E.value.recursive_duplicate(true, recursion_count);
}
} else {
for (const KeyValue<Variant, Variant> &E : _p->variant_map) {
n[E.key] = E.value;
}
}
return n;
}
void Dictionary::operator=(const Dictionary &p_dictionary) {
if (this == &p_dictionary) {
return;
}
_ref(p_dictionary);
}
const void *Dictionary::id() const {
return _p;
}
Dictionary::Dictionary(const Dictionary &p_from) {
_p = nullptr;
_ref(p_from);
}
Dictionary::Dictionary() {
_p = memnew(DictionaryPrivate);
_p->refcount.init();
}
Dictionary::~Dictionary() {
_unref();
}