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/*
* Copyright (C) 2005-2019 Apple Inc. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#pragma once
#include <initializer_list>
#include <wtf/Forward.h>
#include <wtf/HashTable.h>
#include <wtf/IteratorRange.h>
namespace WTF {
template<typename T> struct KeyValuePairKeyExtractor {
static const typename T::KeyType& extract(const T& p) { return p.key; }
};
template<typename KeyArg, typename MappedArg, typename HashArg, typename KeyTraitsArg, typename MappedTraitsArg>
class HashMap final {
WTF_MAKE_FAST_ALLOCATED;
private:
using KeyTraits = KeyTraitsArg;
using MappedTraits = MappedTraitsArg;
struct KeyValuePairTraits : KeyValuePairHashTraits<KeyTraits, MappedTraits> {
static constexpr bool hasIsEmptyValueFunction = true;
static bool isEmptyValue(const typename KeyValuePairHashTraits<KeyTraits, MappedTraits>::TraitType& value)
{
return isHashTraitsEmptyValue<KeyTraits>(value.key);
}
};
public:
using KeyType = typename KeyTraits::TraitType;
using MappedType = typename MappedTraits::TraitType;
using KeyValuePairType = typename KeyValuePairTraits::TraitType;
private:
using MappedPeekType = typename MappedTraits::PeekType;
using MappedTakeType = typename MappedTraits::TakeType;
using HashFunctions = HashArg;
using HashTableType = HashTable<KeyType, KeyValuePairType, KeyValuePairKeyExtractor<KeyValuePairType>, HashFunctions, KeyValuePairTraits, KeyTraits>;
class HashMapKeysProxy;
class HashMapValuesProxy;
using IdentityTranslatorType = typename HashTableType::IdentityTranslatorType;
public:
/*
* Since figuring out the entries of an iterator is confusing, here is a cheat sheet:
* const KeyType& key = iterator->key;
* ValueType& value = iterator->value;
*/
using iterator = HashTableIteratorAdapter<HashTableType, KeyValuePairType>;
using const_iterator = HashTableConstIteratorAdapter<HashTableType, KeyValuePairType>;
using KeysIteratorRange = SizedIteratorRange<HashMap, typename iterator::Keys>;
using KeysConstIteratorRange = SizedIteratorRange<HashMap, typename const_iterator::Keys>;
using ValuesIteratorRange = SizedIteratorRange<HashMap, typename iterator::Values>;
using ValuesConstIteratorRange = SizedIteratorRange<HashMap, typename const_iterator::Values>;
/*
* Since figuring out the entries of an AddResult is confusing, here is a cheat sheet:
* iterator iter = addResult.iterator;
* bool isNewEntry = addResult.isNewEntry;
*/
using AddResult = typename HashTableType::AddResult;
public:
HashMap()
{
}
HashMap(std::initializer_list<KeyValuePairType> initializerList)
{
for (const auto& keyValuePair : initializerList)
add(keyValuePair.key, keyValuePair.value);
}
void swap(HashMap&);
unsigned size() const;
unsigned capacity() const;
bool isEmpty() const;
void reserveInitialCapacity(unsigned keyCount) { m_impl.reserveInitialCapacity(keyCount); }
// iterators iterate over pairs of keys and values
iterator begin();
iterator end();
const_iterator begin() const;
const_iterator end() const;
iterator random() { return m_impl.random(); }
const_iterator random() const { return m_impl.random(); }
KeysIteratorRange keys() { return makeSizedIteratorRange(*this, begin().keys(), end().keys()); }
const KeysConstIteratorRange keys() const { return makeSizedIteratorRange(*this, begin().keys(), end().keys()); }
ValuesIteratorRange values() { return makeSizedIteratorRange(*this, begin().values(), end().values()); }
const ValuesConstIteratorRange values() const { return makeSizedIteratorRange(*this, begin().values(), end().values()); }
iterator find(const KeyType&);
const_iterator find(const KeyType&) const;
bool contains(const KeyType&) const;
MappedPeekType get(const KeyType&) const;
// Same as get(), but aggressively inlined.
MappedPeekType inlineGet(const KeyType&) const;
// Replaces the value but not the key if the key is already present.
// Return value includes both an iterator to the key location,
// and an isNewEntry boolean that's true if a new entry was added.
template<typename V> AddResult set(const KeyType&, V&&);
template<typename V> AddResult set(KeyType&&, V&&);
// Does nothing if the key is already present.
// Return value includes both an iterator to the key location,
// and an isNewEntry boolean that's true if a new entry was added.
template<typename V> AddResult add(const KeyType&, V&&);
template<typename V> AddResult add(KeyType&&, V&&);
// Same as add(), but aggressively inlined.
template<typename V> AddResult fastAdd(const KeyType&, V&&);
template<typename V> AddResult fastAdd(KeyType&&, V&&);
template<typename Functor> AddResult ensure(const KeyType&, Functor&&);
template<typename Functor> AddResult ensure(KeyType&&, Functor&&);
bool remove(const KeyType&);
bool remove(iterator);
template<typename Functor>
bool removeIf(Functor&&);
void clear();
MappedTakeType take(const KeyType&); // efficient combination of get with remove
// An alternate version of find() that finds the object by hashing and comparing
// with some other type, to avoid the cost of type conversion. HashTranslator
// must have the following function members:
// static unsigned hash(const T&);
// static bool equal(const ValueType&, const T&);
template<typename HashTranslator, typename T> iterator find(const T&);
template<typename HashTranslator, typename T> const_iterator find(const T&) const;
template<typename HashTranslator, typename T> bool contains(const T&) const;
template<typename HashTranslator, typename T> MappedPeekType get(const T&) const;
template<typename HashTranslator, typename T> MappedPeekType inlineGet(const T&) const;
// An alternate version of add() that finds the object by hashing and comparing
// with some other type, to avoid the cost of type conversion if the object is already
// in the table. HashTranslator must have the following function members:
// static unsigned hash(const T&);
// static bool equal(const ValueType&, const T&);
// static translate(ValueType&, const T&, unsigned hashCode);
template<typename HashTranslator, typename K, typename V> AddResult add(K&&, V&&);
// Overloads for smart pointer keys that take the raw pointer type as the parameter.
template<typename K = KeyType> typename std::enable_if<IsSmartPtr<K>::value, iterator>::type find(typename GetPtrHelper<K>::PtrType);
template<typename K = KeyType> typename std::enable_if<IsSmartPtr<K>::value, const_iterator>::type find(typename GetPtrHelper<K>::PtrType) const;
template<typename K = KeyType> typename std::enable_if<IsSmartPtr<K>::value, bool>::type contains(typename GetPtrHelper<K>::PtrType) const;
template<typename K = KeyType> typename std::enable_if<IsSmartPtr<K>::value, MappedPeekType>::type inlineGet(typename GetPtrHelper<K>::PtrType) const;
template<typename K = KeyType> typename std::enable_if<IsSmartPtr<K>::value, MappedPeekType>::type get(typename GetPtrHelper<K>::PtrType) const;
template<typename K = KeyType> typename std::enable_if<IsSmartPtr<K>::value, bool>::type remove(typename GetPtrHelper<K>::PtrType);
template<typename K = KeyType> typename std::enable_if<IsSmartPtr<K>::value, MappedTakeType>::type take(typename GetPtrHelper<K>::PtrType);
void checkConsistency() const;
static bool isValidKey(const KeyType&);
private:
template<typename K, typename V>
AddResult inlineSet(K&&, V&&);
template<typename K, typename V>
AddResult inlineAdd(K&&, V&&);
template<typename K, typename F>
AddResult inlineEnsure(K&&, F&&);
HashTableType m_impl;
};
template<typename ValueTraits, typename HashFunctions>
struct HashMapTranslator {
template<typename T> static unsigned hash(const T& key) { return HashFunctions::hash(key); }
template<typename T, typename U> static bool equal(const T& a, const U& b) { return HashFunctions::equal(a, b); }
template<typename T, typename U, typename V> static void translate(T& location, U&& key, V&& mapped)
{
ValueTraits::KeyTraits::assignToEmpty(location.key, std::forward<U>(key));
ValueTraits::ValueTraits::assignToEmpty(location.value, std::forward<V>(mapped));
}
};
template<typename ValueTraits, typename HashFunctions>
struct HashMapEnsureTranslator {
template<typename T> static unsigned hash(const T& key) { return HashFunctions::hash(key); }
template<typename T, typename U> static bool equal(const T& a, const U& b) { return HashFunctions::equal(a, b); }
template<typename T, typename U, typename Functor> static void translate(T& location, U&& key, Functor&& functor)
{
ValueTraits::KeyTraits::assignToEmpty(location.key, std::forward<U>(key));
ValueTraits::ValueTraits::assignToEmpty(location.value, functor());
}
};
template<typename ValueTraits, typename Translator>
struct HashMapTranslatorAdapter {
template<typename T> static unsigned hash(const T& key) { return Translator::hash(key); }
template<typename T, typename U> static bool equal(const T& a, const U& b) { return Translator::equal(a, b); }
template<typename T, typename U, typename V> static void translate(T& location, U&& key, V&& mapped, unsigned hashCode)
{
Translator::translate(location.key, key, hashCode);
location.value = std::forward<V>(mapped);
}
};
template<typename T, typename U, typename V, typename W, typename X>
inline void HashMap<T, U, V, W, X>::swap(HashMap& other)
{
m_impl.swap(other.m_impl);
}
template<typename T, typename U, typename V, typename W, typename X>
inline unsigned HashMap<T, U, V, W, X>::size() const
{
return m_impl.size();
}
template<typename T, typename U, typename V, typename W, typename X>
inline unsigned HashMap<T, U, V, W, X>::capacity() const
{
return m_impl.capacity();
}
template<typename T, typename U, typename V, typename W, typename X>
inline bool HashMap<T, U, V, W, X>::isEmpty() const
{
return m_impl.isEmpty();
}
template<typename T, typename U, typename V, typename W, typename X>
inline auto HashMap<T, U, V, W, X>::begin() -> iterator
{
return m_impl.begin();
}
template<typename T, typename U, typename V, typename W, typename X>
inline auto HashMap<T, U, V, W, X>::end() -> iterator
{
return m_impl.end();
}
template<typename T, typename U, typename V, typename W, typename X>
inline auto HashMap<T, U, V, W, X>::begin() const -> const_iterator
{
return m_impl.begin();
}
template<typename T, typename U, typename V, typename W, typename X>
inline auto HashMap<T, U, V, W, X>::end() const -> const_iterator
{
return m_impl.end();
}
template<typename T, typename U, typename V, typename W, typename X>
inline auto HashMap<T, U, V, W, X>::find(const KeyType& key) -> iterator
{
return m_impl.find(key);
}
template<typename T, typename U, typename V, typename W, typename X>
inline auto HashMap<T, U, V, W, X>::find(const KeyType& key) const -> const_iterator
{
return m_impl.find(key);
}
template<typename T, typename U, typename V, typename W, typename X>
inline bool HashMap<T, U, V, W, X>::contains(const KeyType& key) const
{
return m_impl.contains(key);
}
template<typename T, typename U, typename V, typename W, typename X>
template<typename HashTranslator, typename TYPE>
inline typename HashMap<T, U, V, W, X>::iterator
HashMap<T, U, V, W, X>::find(const TYPE& value)
{
return m_impl.template find<HashMapTranslatorAdapter<KeyValuePairTraits, HashTranslator>>(value);
}
template<typename T, typename U, typename V, typename W, typename X>
template<typename HashTranslator, typename TYPE>
inline typename HashMap<T, U, V, W, X>::const_iterator
HashMap<T, U, V, W, X>::find(const TYPE& value) const
{
return m_impl.template find<HashMapTranslatorAdapter<KeyValuePairTraits, HashTranslator>>(value);
}
template<typename T, typename U, typename V, typename W, typename X>
template<typename HashTranslator, typename TYPE>
auto HashMap<T, U, V, W, X>::get(const TYPE& value) const -> MappedPeekType
{
auto* entry = const_cast<HashTableType&>(m_impl).template lookup<HashMapTranslatorAdapter<KeyValuePairTraits, HashTranslator>>(value);
if (!entry)
return MappedTraits::peek(MappedTraits::emptyValue());
return MappedTraits::peek(entry->value);
}
template<typename T, typename U, typename V, typename W, typename X>
template<typename HashTranslator, typename TYPE>
auto HashMap<T, U, V, W, X>::inlineGet(const TYPE& value) const -> MappedPeekType
{
auto* entry = const_cast<HashTableType&>(m_impl).template inlineLookup<HashMapTranslatorAdapter<KeyValuePairTraits, HashTranslator>>(value);
if (!entry)
return MappedTraits::peek(MappedTraits::emptyValue());
return MappedTraits::peek(entry->value);
}
template<typename T, typename U, typename V, typename W, typename X>
template<typename HashTranslator, typename TYPE>
inline bool HashMap<T, U, V, W, X>::contains(const TYPE& value) const
{
return m_impl.template contains<HashMapTranslatorAdapter<KeyValuePairTraits, HashTranslator>>(value);
}
template<typename KeyArg, typename MappedArg, typename HashArg, typename KeyTraitsArg, typename MappedTraitsArg>
template<typename K, typename V>
auto HashMap<KeyArg, MappedArg, HashArg, KeyTraitsArg, MappedTraitsArg>::inlineSet(K&& key, V&& value) -> AddResult
{
AddResult result = inlineAdd(std::forward<K>(key), std::forward<V>(value));
if (!result.isNewEntry) {
// The inlineAdd call above found an existing hash table entry; we need to set the mapped value.
result.iterator->value = std::forward<V>(value);
}
return result;
}
template<typename KeyArg, typename MappedArg, typename HashArg, typename KeyTraitsArg, typename MappedTraitsArg>
template<typename K, typename V>
ALWAYS_INLINE auto HashMap<KeyArg, MappedArg, HashArg, KeyTraitsArg, MappedTraitsArg>::inlineAdd(K&& key, V&& value) -> AddResult
{
return m_impl.template add<HashMapTranslator<KeyValuePairTraits, HashFunctions>>(std::forward<K>(key), std::forward<V>(value));
}
template<typename KeyArg, typename MappedArg, typename HashArg, typename KeyTraitsArg, typename MappedTraitsArg>
template<typename K, typename F>
ALWAYS_INLINE auto HashMap<KeyArg, MappedArg, HashArg, KeyTraitsArg, MappedTraitsArg>::inlineEnsure(K&& key, F&& functor) -> AddResult
{
return m_impl.template add<HashMapEnsureTranslator<KeyValuePairTraits, HashFunctions>>(std::forward<K>(key), std::forward<F>(functor));
}
template<typename KeyArg, typename MappedArg, typename HashArg, typename KeyTraitsArg, typename MappedTraitsArg>
template<typename T>
auto HashMap<KeyArg, MappedArg, HashArg, KeyTraitsArg, MappedTraitsArg>::set(const KeyType& key, T&& mapped) -> AddResult
{
return inlineSet(key, std::forward<T>(mapped));
}
template<typename KeyArg, typename MappedArg, typename HashArg, typename KeyTraitsArg, typename MappedTraitsArg>
template<typename T>
auto HashMap<KeyArg, MappedArg, HashArg, KeyTraitsArg, MappedTraitsArg>::set(KeyType&& key, T&& mapped) -> AddResult
{
return inlineSet(WTFMove(key), std::forward<T>(mapped));
}
template<typename KeyArg, typename MappedArg, typename HashArg, typename KeyTraitsArg, typename MappedTraitsArg>
template<typename HashTranslator, typename K, typename V>
auto HashMap<KeyArg, MappedArg, HashArg, KeyTraitsArg, MappedTraitsArg>::add(K&& key, V&& value) -> AddResult
{
return m_impl.template addPassingHashCode<HashMapTranslatorAdapter<KeyValuePairTraits, HashTranslator>>(std::forward<K>(key), std::forward<V>(value));
}
template<typename KeyArg, typename MappedArg, typename HashArg, typename KeyTraitsArg, typename MappedTraitsArg>
template<typename T>
auto HashMap<KeyArg, MappedArg, HashArg, KeyTraitsArg, MappedTraitsArg>::add(const KeyType& key, T&& mapped) -> AddResult
{
return inlineAdd(key, std::forward<T>(mapped));
}
template<typename KeyArg, typename MappedArg, typename HashArg, typename KeyTraitsArg, typename MappedTraitsArg>
template<typename T>
auto HashMap<KeyArg, MappedArg, HashArg, KeyTraitsArg, MappedTraitsArg>::add(KeyType&& key, T&& mapped) -> AddResult
{
return inlineAdd(WTFMove(key), std::forward<T>(mapped));
}
template<typename KeyArg, typename MappedArg, typename HashArg, typename KeyTraitsArg, typename MappedTraitsArg>
template<typename T>
ALWAYS_INLINE auto HashMap<KeyArg, MappedArg, HashArg, KeyTraitsArg, MappedTraitsArg>::fastAdd(const KeyType& key, T&& mapped) -> AddResult
{
return inlineAdd(key, std::forward<T>(mapped));
}
template<typename KeyArg, typename MappedArg, typename HashArg, typename KeyTraitsArg, typename MappedTraitsArg>
template<typename T>
ALWAYS_INLINE auto HashMap<KeyArg, MappedArg, HashArg, KeyTraitsArg, MappedTraitsArg>::fastAdd(KeyType&& key, T&& mapped) -> AddResult
{
return inlineAdd(WTFMove(key), std::forward<T>(mapped));
}
template<typename KeyArg, typename MappedArg, typename HashArg, typename KeyTraitsArg, typename MappedTraitsArg>
template<typename Functor>
auto HashMap<KeyArg, MappedArg, HashArg, KeyTraitsArg, MappedTraitsArg>::ensure(const KeyType& key, Functor&& functor) -> AddResult
{
return inlineEnsure(key, std::forward<Functor>(functor));
}
template<typename KeyArg, typename MappedArg, typename HashArg, typename KeyTraitsArg, typename MappedTraitsArg>
template<typename Functor>
auto HashMap<KeyArg, MappedArg, HashArg, KeyTraitsArg, MappedTraitsArg>::ensure(KeyType&& key, Functor&& functor) -> AddResult
{
return inlineEnsure(std::forward<KeyType>(key), std::forward<Functor>(functor));
}
template<typename T, typename U, typename V, typename W, typename MappedTraits>
inline auto HashMap<T, U, V, W, MappedTraits>::get(const KeyType& key) const -> MappedPeekType
{
return get<IdentityTranslatorType>(key);
}
template<typename T, typename U, typename V, typename W, typename MappedTraits>
ALWAYS_INLINE auto HashMap<T, U, V, W, MappedTraits>::inlineGet(const KeyType& key) const -> MappedPeekType
{
KeyValuePairType* entry = const_cast<HashTableType&>(m_impl).template inlineLookup<IdentityTranslatorType>(key);
if (!entry)
return MappedTraits::peek(MappedTraits::emptyValue());
return MappedTraits::peek(entry->value);
}
template<typename T, typename U, typename V, typename W, typename X>
inline bool HashMap<T, U, V, W, X>::remove(iterator it)
{
if (it.m_impl == m_impl.end())
return false;
m_impl.internalCheckTableConsistency();
m_impl.removeWithoutEntryConsistencyCheck(it.m_impl);
return true;
}
template<typename T, typename U, typename V, typename W, typename X>
template<typename Functor>
inline bool HashMap<T, U, V, W, X>::removeIf(Functor&& functor)
{
return m_impl.removeIf(std::forward<Functor>(functor));
}
template<typename T, typename U, typename V, typename W, typename X>
inline bool HashMap<T, U, V, W, X>::remove(const KeyType& key)
{
return remove(find(key));
}
template<typename T, typename U, typename V, typename W, typename X>
inline void HashMap<T, U, V, W, X>::clear()
{
m_impl.clear();
}
template<typename T, typename U, typename V, typename W, typename MappedTraits>
auto HashMap<T, U, V, W, MappedTraits>::take(const KeyType& key) -> MappedTakeType
{
iterator it = find(key);
if (it == end())
return MappedTraits::take(MappedTraits::emptyValue());
auto value = MappedTraits::take(WTFMove(it->value));
remove(it);
return value;
}
template<typename T, typename U, typename V, typename W, typename X>
template<typename K>
inline auto HashMap<T, U, V, W, X>::find(typename GetPtrHelper<K>::PtrType key) -> typename std::enable_if<IsSmartPtr<K>::value, iterator>::type
{
return m_impl.template find<HashMapTranslator<KeyValuePairTraits, HashFunctions>>(key);
}
template<typename T, typename U, typename V, typename W, typename X>
template<typename K>
inline auto HashMap<T, U, V, W, X>::find(typename GetPtrHelper<K>::PtrType key) const -> typename std::enable_if<IsSmartPtr<K>::value, const_iterator>::type
{
return m_impl.template find<HashMapTranslator<KeyValuePairTraits, HashFunctions>>(key);
}
template<typename T, typename U, typename V, typename W, typename X>
template<typename K>
inline auto HashMap<T, U, V, W, X>::contains(typename GetPtrHelper<K>::PtrType key) const -> typename std::enable_if<IsSmartPtr<K>::value, bool>::type
{
return m_impl.template contains<HashMapTranslator<KeyValuePairTraits, HashFunctions>>(key);
}
template<typename T, typename U, typename V, typename W, typename X>
template<typename K>
inline auto HashMap<T, U, V, W, X>::inlineGet(typename GetPtrHelper<K>::PtrType key) const -> typename std::enable_if<IsSmartPtr<K>::value, MappedPeekType>::type
{
KeyValuePairType* entry = const_cast<HashTableType&>(m_impl).template inlineLookup<HashMapTranslator<KeyValuePairTraits, HashFunctions>>(key);
if (!entry)
return MappedTraits::peek(MappedTraits::emptyValue());
return MappedTraits::peek(entry->value);
}
template<typename T, typename U, typename V, typename W, typename X>
template<typename K>
auto HashMap<T, U, V, W, X>::get(typename GetPtrHelper<K>::PtrType key) const -> typename std::enable_if<IsSmartPtr<K>::value, MappedPeekType>::type
{
return inlineGet(key);
}
template<typename T, typename U, typename V, typename W, typename X>
template<typename K>
inline auto HashMap<T, U, V, W, X>::remove(typename GetPtrHelper<K>::PtrType key) -> typename std::enable_if<IsSmartPtr<K>::value, bool>::type
{
return remove(find(key));
}
template<typename T, typename U, typename V, typename W, typename X>
template<typename K>
inline auto HashMap<T, U, V, W, X>::take(typename GetPtrHelper<K>::PtrType key) -> typename std::enable_if<IsSmartPtr<K>::value, MappedTakeType>::type
{
iterator it = find(key);
if (it == end())
return MappedTraits::take(MappedTraits::emptyValue());
auto value = MappedTraits::take(WTFMove(it->value));
remove(it);
return value;
}
template<typename T, typename U, typename V, typename W, typename X>
inline void HashMap<T, U, V, W, X>::checkConsistency() const
{
m_impl.checkTableConsistency();
}
template<typename T, typename U, typename V, typename W, typename X>
inline bool HashMap<T, U, V, W, X>::isValidKey(const KeyType& key)
{
if (KeyTraits::isDeletedValue(key))
return false;
if (HashFunctions::safeToCompareToEmptyOrDeleted) {
if (key == KeyTraits::emptyValue())
return false;
} else {
if (isHashTraitsEmptyValue<KeyTraits>(key))
return false;
}
return true;
}
template<typename T, typename U, typename V, typename W, typename X>
bool operator==(const HashMap<T, U, V, W, X>& a, const HashMap<T, U, V, W, X>& b)
{
if (a.size() != b.size())
return false;
typedef typename HashMap<T, U, V, W, X>::const_iterator const_iterator;
const_iterator end = a.end();
const_iterator notFound = b.end();
for (const_iterator it = a.begin(); it != end; ++it) {
const_iterator bPos = b.find(it->key);
if (bPos == notFound || it->value != bPos->value)
return false;
}
return true;
}
template<typename T, typename U, typename V, typename W, typename X>
inline bool operator!=(const HashMap<T, U, V, W, X>& a, const HashMap<T, U, V, W, X>& b)
{
return !(a == b);
}
} // namespace WTF
using WTF::HashMap;