ladybird/AK/Vector.h
Jelle Raaijmakers 65a9eb1fdf AK: Simplify Vector::padded_capacity
We don't need to do `max(4, ...)` if the RHS always adds 4.
2023-06-13 13:08:14 +02:00

874 lines
24 KiB
C++

/*
* Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2021, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Assertions.h>
#include <AK/Error.h>
#include <AK/Find.h>
#include <AK/Forward.h>
#include <AK/Iterator.h>
#include <AK/Optional.h>
#include <AK/ReverseIterator.h>
#include <AK/Span.h>
#include <AK/StdLibExtras.h>
#include <AK/Traits.h>
#include <AK/TypedTransfer.h>
#include <AK/kmalloc.h>
#include <initializer_list>
namespace AK {
namespace Detail {
template<typename StorageType, bool>
struct CanBePlacedInsideVectorHelper;
template<typename StorageType>
struct CanBePlacedInsideVectorHelper<StorageType, true> {
template<typename U>
static constexpr bool value = requires(U && u) { StorageType { &u }; };
};
template<typename StorageType>
struct CanBePlacedInsideVectorHelper<StorageType, false> {
template<typename U>
static constexpr bool value = requires(U && u) { StorageType(forward<U>(u)); };
};
}
template<typename T, size_t inline_capacity>
requires(!IsRvalueReference<T>) class Vector {
private:
static constexpr bool contains_reference = IsLvalueReference<T>;
using StorageType = Conditional<contains_reference, RawPtr<RemoveReference<T>>, T>;
using VisibleType = RemoveReference<T>;
template<typename U>
static constexpr bool CanBePlacedInsideVector = Detail::CanBePlacedInsideVectorHelper<StorageType, contains_reference>::template value<U>;
public:
using ValueType = T;
Vector()
{
}
Vector(std::initializer_list<T> list)
requires(!IsLvalueReference<T>)
{
ensure_capacity(list.size());
for (auto& item : list)
unchecked_append(item);
}
Vector(Vector&& other)
: m_size(other.m_size)
, m_capacity(other.m_capacity)
, m_outline_buffer(other.m_outline_buffer)
{
if constexpr (inline_capacity > 0) {
if (!m_outline_buffer) {
TypedTransfer<T>::move(inline_buffer(), other.inline_buffer(), m_size);
TypedTransfer<T>::delete_(other.inline_buffer(), m_size);
}
}
other.m_outline_buffer = nullptr;
other.m_size = 0;
other.reset_capacity();
}
Vector(Vector const& other)
{
ensure_capacity(other.size());
TypedTransfer<StorageType>::copy(data(), other.data(), other.size());
m_size = other.size();
}
explicit Vector(ReadonlySpan<T> other)
requires(!IsLvalueReference<T>)
{
ensure_capacity(other.size());
TypedTransfer<StorageType>::copy(data(), other.data(), other.size());
m_size = other.size();
}
template<size_t other_inline_capacity>
Vector(Vector<T, other_inline_capacity> const& other)
{
ensure_capacity(other.size());
TypedTransfer<StorageType>::copy(data(), other.data(), other.size());
m_size = other.size();
}
~Vector()
{
clear();
}
Span<StorageType> span() { return { data(), size() }; }
ReadonlySpan<StorageType> span() const { return { data(), size() }; }
operator Span<StorageType>() { return span(); }
operator ReadonlySpan<StorageType>() const { return span(); }
bool is_empty() const { return size() == 0; }
ALWAYS_INLINE size_t size() const { return m_size; }
size_t capacity() const { return m_capacity; }
ALWAYS_INLINE StorageType* data()
{
if constexpr (inline_capacity > 0)
return m_outline_buffer ? m_outline_buffer : inline_buffer();
return m_outline_buffer;
}
ALWAYS_INLINE StorageType const* data() const
{
if constexpr (inline_capacity > 0)
return m_outline_buffer ? m_outline_buffer : inline_buffer();
return m_outline_buffer;
}
ALWAYS_INLINE VisibleType const& at(size_t i) const
{
VERIFY(i < m_size);
if constexpr (contains_reference)
return *data()[i];
else
return data()[i];
}
ALWAYS_INLINE VisibleType& at(size_t i)
{
VERIFY(i < m_size);
if constexpr (contains_reference)
return *data()[i];
else
return data()[i];
}
ALWAYS_INLINE VisibleType const& operator[](size_t i) const { return at(i); }
ALWAYS_INLINE VisibleType& operator[](size_t i) { return at(i); }
VisibleType const& first() const { return at(0); }
VisibleType& first() { return at(0); }
VisibleType const& last() const { return at(size() - 1); }
VisibleType& last() { return at(size() - 1); }
template<typename TUnaryPredicate>
Optional<VisibleType&> first_matching(TUnaryPredicate const& predicate)
requires(!contains_reference)
{
for (size_t i = 0; i < size(); ++i) {
if (predicate(at(i))) {
return at(i);
}
}
return {};
}
template<typename TUnaryPredicate>
Optional<VisibleType const&> first_matching(TUnaryPredicate const& predicate) const
requires(!contains_reference)
{
for (size_t i = 0; i < size(); ++i) {
if (predicate(at(i))) {
return Optional<VisibleType const&>(at(i));
}
}
return {};
}
template<typename TUnaryPredicate>
Optional<VisibleType&> last_matching(TUnaryPredicate const& predicate)
requires(!contains_reference)
{
for (ssize_t i = size() - 1; i >= 0; --i) {
if (predicate(at(i))) {
return at(i);
}
}
return {};
}
template<typename V>
bool operator==(V const& other) const
{
if (m_size != other.size())
return false;
return TypedTransfer<StorageType>::compare(data(), other.data(), size());
}
template<typename V>
bool contains_slow(V const& value) const
{
for (size_t i = 0; i < size(); ++i) {
if (Traits<VisibleType>::equals(at(i), value))
return true;
}
return false;
}
bool contains_in_range(VisibleType const& value, size_t const start, size_t const end) const
{
VERIFY(start <= end);
VERIFY(end < size());
for (size_t i = start; i <= end; ++i) {
if (Traits<VisibleType>::equals(at(i), value))
return true;
}
return false;
}
#ifndef KERNEL
template<typename U = T>
void insert(size_t index, U&& value)
requires(CanBePlacedInsideVector<U>)
{
MUST(try_insert<U>(index, forward<U>(value)));
}
template<typename TUnaryPredicate, typename U = T>
void insert_before_matching(U&& value, TUnaryPredicate const& predicate, size_t first_index = 0, size_t* inserted_index = nullptr)
requires(CanBePlacedInsideVector<U>)
{
MUST(try_insert_before_matching(forward<U>(value), predicate, first_index, inserted_index));
}
void extend(Vector&& other)
{
MUST(try_extend(move(other)));
}
void extend(Vector const& other)
{
MUST(try_extend(other));
}
#endif
ALWAYS_INLINE void append(T&& value)
{
if constexpr (contains_reference)
MUST(try_append(value));
else
MUST(try_append(move(value)));
}
ALWAYS_INLINE void append(T const& value)
requires(!contains_reference)
{
MUST(try_append(T(value)));
}
#ifndef KERNEL
void append(StorageType const* values, size_t count)
{
MUST(try_append(values, count));
}
#endif
template<typename U = T>
ALWAYS_INLINE void unchecked_append(U&& value)
requires(CanBePlacedInsideVector<U>)
{
VERIFY((size() + 1) <= capacity());
if constexpr (contains_reference)
new (slot(m_size)) StorageType(&value);
else
new (slot(m_size)) StorageType(forward<U>(value));
++m_size;
}
ALWAYS_INLINE void unchecked_append(StorageType const* values, size_t count)
{
if (count == 0)
return;
VERIFY((size() + count) <= capacity());
TypedTransfer<StorageType>::copy(slot(m_size), values, count);
m_size += count;
}
#ifndef KERNEL
template<class... Args>
void empend(Args&&... args)
requires(!contains_reference)
{
MUST(try_empend(forward<Args>(args)...));
}
template<typename U = T>
void prepend(U&& value)
requires(CanBePlacedInsideVector<U>)
{
MUST(try_insert(0, forward<U>(value)));
}
void prepend(Vector&& other)
{
MUST(try_prepend(move(other)));
}
void prepend(StorageType const* values, size_t count)
{
MUST(try_prepend(values, count));
}
#endif
// FIXME: What about assigning from a vector with lower inline capacity?
Vector& operator=(Vector&& other)
{
if (this != &other) {
clear();
m_size = other.m_size;
m_capacity = other.m_capacity;
m_outline_buffer = other.m_outline_buffer;
if constexpr (inline_capacity > 0) {
if (!m_outline_buffer) {
for (size_t i = 0; i < m_size; ++i) {
new (&inline_buffer()[i]) StorageType(move(other.inline_buffer()[i]));
other.inline_buffer()[i].~StorageType();
}
}
}
other.m_outline_buffer = nullptr;
other.m_size = 0;
other.reset_capacity();
}
return *this;
}
Vector& operator=(Vector const& other)
{
if (this != &other) {
clear();
ensure_capacity(other.size());
TypedTransfer<StorageType>::copy(data(), other.data(), other.size());
m_size = other.size();
}
return *this;
}
template<size_t other_inline_capacity>
Vector& operator=(Vector<T, other_inline_capacity> const& other)
{
clear();
ensure_capacity(other.size());
TypedTransfer<StorageType>::copy(data(), other.data(), other.size());
m_size = other.size();
return *this;
}
void clear()
{
clear_with_capacity();
if (m_outline_buffer) {
kfree_sized(m_outline_buffer, m_capacity * sizeof(StorageType));
m_outline_buffer = nullptr;
}
reset_capacity();
}
void clear_with_capacity()
{
for (size_t i = 0; i < m_size; ++i)
data()[i].~StorageType();
m_size = 0;
}
void remove(size_t index)
{
VERIFY(index < m_size);
if constexpr (Traits<StorageType>::is_trivial()) {
TypedTransfer<StorageType>::copy(slot(index), slot(index + 1), m_size - index - 1);
} else {
at(index).~StorageType();
for (size_t i = index + 1; i < m_size; ++i) {
new (slot(i - 1)) StorageType(move(at(i)));
at(i).~StorageType();
}
}
--m_size;
}
void remove(size_t index, size_t count)
{
if (count == 0)
return;
VERIFY(index + count > index);
VERIFY(index + count <= m_size);
if constexpr (Traits<StorageType>::is_trivial()) {
TypedTransfer<StorageType>::copy(slot(index), slot(index + count), m_size - index - count);
} else {
for (size_t i = index; i < index + count; i++)
at(i).~StorageType();
for (size_t i = index + count; i < m_size; ++i) {
new (slot(i - count)) StorageType(move(at(i)));
at(i).~StorageType();
}
}
m_size -= count;
}
template<typename TUnaryPredicate>
bool remove_first_matching(TUnaryPredicate const& predicate)
{
for (size_t i = 0; i < size(); ++i) {
if (predicate(at(i))) {
remove(i);
return true;
}
}
return false;
}
template<typename TUnaryPredicate>
bool remove_all_matching(TUnaryPredicate const& predicate)
{
bool something_was_removed = false;
for (size_t i = 0; i < size();) {
if (predicate(at(i))) {
remove(i);
something_was_removed = true;
} else {
++i;
}
}
return something_was_removed;
}
ALWAYS_INLINE T take_last()
{
VERIFY(!is_empty());
auto value = move(raw_last());
if constexpr (!contains_reference)
last().~T();
--m_size;
if constexpr (contains_reference)
return *value;
else
return value;
}
T take_first()
{
VERIFY(!is_empty());
auto value = move(raw_first());
remove(0);
if constexpr (contains_reference)
return *value;
else
return value;
}
T take(size_t index)
{
auto value = move(raw_at(index));
remove(index);
if constexpr (contains_reference)
return *value;
else
return value;
}
T unstable_take(size_t index)
{
VERIFY(index < m_size);
swap(raw_at(index), raw_at(m_size - 1));
return take_last();
}
template<typename U = T>
ErrorOr<void> try_insert(size_t index, U&& value)
requires(CanBePlacedInsideVector<U>)
{
if (index > size())
return Error::from_errno(EINVAL);
if (index == size())
return try_append(forward<U>(value));
TRY(try_grow_capacity(size() + 1));
++m_size;
if constexpr (Traits<StorageType>::is_trivial()) {
TypedTransfer<StorageType>::move(slot(index + 1), slot(index), m_size - index - 1);
} else {
for (size_t i = size() - 1; i > index; --i) {
new (slot(i)) StorageType(move(at(i - 1)));
at(i - 1).~StorageType();
}
}
if constexpr (contains_reference)
new (slot(index)) StorageType(&value);
else
new (slot(index)) StorageType(forward<U>(value));
return {};
}
template<typename TUnaryPredicate, typename U = T>
ErrorOr<void> try_insert_before_matching(U&& value, TUnaryPredicate const& predicate, size_t first_index = 0, size_t* inserted_index = nullptr)
requires(CanBePlacedInsideVector<U>)
{
for (size_t i = first_index; i < size(); ++i) {
if (predicate(at(i))) {
TRY(try_insert(i, forward<U>(value)));
if (inserted_index)
*inserted_index = i;
return {};
}
}
TRY(try_append(forward<U>(value)));
if (inserted_index)
*inserted_index = size() - 1;
return {};
}
ErrorOr<void> try_extend(Vector&& other)
{
if (is_empty() && capacity() <= other.capacity()) {
*this = move(other);
return {};
}
auto other_size = other.size();
Vector tmp = move(other);
TRY(try_grow_capacity(size() + other_size));
TypedTransfer<StorageType>::move(data() + m_size, tmp.data(), other_size);
m_size += other_size;
return {};
}
ErrorOr<void> try_extend(Vector const& other)
{
TRY(try_grow_capacity(size() + other.size()));
TypedTransfer<StorageType>::copy(data() + m_size, other.data(), other.size());
m_size += other.m_size;
return {};
}
ErrorOr<void> try_append(T&& value)
{
TRY(try_grow_capacity(size() + 1));
if constexpr (contains_reference)
new (slot(m_size)) StorageType(&value);
else
new (slot(m_size)) StorageType(move(value));
++m_size;
return {};
}
ErrorOr<void> try_append(T const& value)
requires(!contains_reference)
{
return try_append(T(value));
}
ErrorOr<void> try_append(StorageType const* values, size_t count)
{
if (count == 0)
return {};
TRY(try_grow_capacity(size() + count));
TypedTransfer<StorageType>::copy(slot(m_size), values, count);
m_size += count;
return {};
}
template<class... Args>
ErrorOr<void> try_empend(Args&&... args)
requires(!contains_reference)
{
TRY(try_grow_capacity(m_size + 1));
new (slot(m_size)) StorageType { forward<Args>(args)... };
++m_size;
return {};
}
template<typename U = T>
ErrorOr<void> try_prepend(U&& value)
requires(CanBePlacedInsideVector<U>)
{
return try_insert(0, forward<U>(value));
}
ErrorOr<void> try_prepend(Vector&& other)
{
if (other.is_empty())
return {};
if (is_empty()) {
*this = move(other);
return {};
}
auto other_size = other.size();
TRY(try_grow_capacity(size() + other_size));
for (size_t i = size() + other_size - 1; i >= other.size(); --i) {
new (slot(i)) StorageType(move(at(i - other_size)));
at(i - other_size).~StorageType();
}
Vector tmp = move(other);
TypedTransfer<StorageType>::move(slot(0), tmp.data(), tmp.size());
m_size += other_size;
return {};
}
ErrorOr<void> try_prepend(StorageType const* values, size_t count)
{
if (count == 0)
return {};
TRY(try_grow_capacity(size() + count));
TypedTransfer<StorageType>::move(slot(count), slot(0), m_size);
TypedTransfer<StorageType>::copy(slot(0), values, count);
m_size += count;
return {};
}
ErrorOr<void> try_grow_capacity(size_t needed_capacity)
{
if (m_capacity >= needed_capacity)
return {};
return try_ensure_capacity(padded_capacity(needed_capacity));
}
ErrorOr<void> try_ensure_capacity(size_t needed_capacity)
{
if (m_capacity >= needed_capacity)
return {};
size_t new_capacity = kmalloc_good_size(needed_capacity * sizeof(StorageType)) / sizeof(StorageType);
auto* new_buffer = static_cast<StorageType*>(kmalloc_array(new_capacity, sizeof(StorageType)));
if (new_buffer == nullptr)
return Error::from_errno(ENOMEM);
if constexpr (Traits<StorageType>::is_trivial()) {
TypedTransfer<StorageType>::copy(new_buffer, data(), m_size);
} else {
for (size_t i = 0; i < m_size; ++i) {
new (&new_buffer[i]) StorageType(move(at(i)));
at(i).~StorageType();
}
}
if (m_outline_buffer)
kfree_sized(m_outline_buffer, m_capacity * sizeof(StorageType));
m_outline_buffer = new_buffer;
m_capacity = new_capacity;
return {};
}
ErrorOr<void> try_resize(size_t new_size, bool keep_capacity = false)
requires(!contains_reference)
{
if (new_size <= size()) {
shrink(new_size, keep_capacity);
return {};
}
TRY(try_ensure_capacity(new_size));
for (size_t i = size(); i < new_size; ++i)
new (slot(i)) StorageType {};
m_size = new_size;
return {};
}
ErrorOr<void> try_resize_and_keep_capacity(size_t new_size)
requires(!contains_reference)
{
return try_resize(new_size, true);
}
void grow_capacity(size_t needed_capacity)
{
MUST(try_grow_capacity(needed_capacity));
}
void ensure_capacity(size_t needed_capacity)
{
MUST(try_ensure_capacity(needed_capacity));
}
void shrink(size_t new_size, bool keep_capacity = false)
{
VERIFY(new_size <= size());
if (new_size == size())
return;
if (new_size == 0) {
if (keep_capacity)
clear_with_capacity();
else
clear();
return;
}
for (size_t i = new_size; i < size(); ++i)
at(i).~StorageType();
m_size = new_size;
}
void resize(size_t new_size, bool keep_capacity = false)
requires(!contains_reference)
{
MUST(try_resize(new_size, keep_capacity));
}
void resize_and_keep_capacity(size_t new_size)
requires(!contains_reference)
{
MUST(try_resize_and_keep_capacity(new_size));
}
void shrink_to_fit()
{
if (size() == capacity())
return;
Vector new_vector;
new_vector.ensure_capacity(size());
for (auto& element : *this) {
new_vector.unchecked_append(move(element));
}
*this = move(new_vector);
}
using ConstIterator = SimpleIterator<Vector const, VisibleType const>;
using Iterator = SimpleIterator<Vector, VisibleType>;
using ReverseIterator = SimpleReverseIterator<Vector, VisibleType>;
using ReverseConstIterator = SimpleReverseIterator<Vector const, VisibleType const>;
ConstIterator begin() const { return ConstIterator::begin(*this); }
Iterator begin() { return Iterator::begin(*this); }
ReverseIterator rbegin() { return ReverseIterator::rbegin(*this); }
ReverseConstIterator rbegin() const { return ReverseConstIterator::rbegin(*this); }
ConstIterator end() const { return ConstIterator::end(*this); }
Iterator end() { return Iterator::end(*this); }
ReverseIterator rend() { return ReverseIterator::rend(*this); }
ReverseConstIterator rend() const { return ReverseConstIterator::rend(*this); }
ALWAYS_INLINE constexpr auto in_reverse()
{
return ReverseWrapper::in_reverse(*this);
}
ALWAYS_INLINE constexpr auto in_reverse() const
{
return ReverseWrapper::in_reverse(*this);
}
template<typename TUnaryPredicate>
ConstIterator find_if(TUnaryPredicate&& finder) const
{
return AK::find_if(begin(), end(), forward<TUnaryPredicate>(finder));
}
template<typename TUnaryPredicate>
Iterator find_if(TUnaryPredicate&& finder)
{
return AK::find_if(begin(), end(), forward<TUnaryPredicate>(finder));
}
ConstIterator find(VisibleType const& value) const
{
return AK::find(begin(), end(), value);
}
Iterator find(VisibleType const& value)
{
return AK::find(begin(), end(), value);
}
Optional<size_t> find_first_index(VisibleType const& value) const
{
if (auto const index = AK::find_index(begin(), end(), value);
index < size()) {
return index;
}
return {};
}
template<typename TUnaryPredicate>
Optional<size_t> find_first_index_if(TUnaryPredicate&& finder) const
{
auto maybe_result = AK::find_if(begin(), end(), finder);
if (maybe_result == end())
return {};
return maybe_result.index();
}
void reverse()
{
for (size_t i = 0; i < size() / 2; ++i)
AK::swap(at(i), at(size() - i - 1));
}
private:
void reset_capacity()
{
m_capacity = inline_capacity;
}
static size_t padded_capacity(size_t capacity)
{
return 4 + capacity + capacity / 4;
}
StorageType* slot(size_t i) { return &data()[i]; }
StorageType const* slot(size_t i) const { return &data()[i]; }
StorageType* inline_buffer()
{
static_assert(inline_capacity > 0);
return reinterpret_cast<StorageType*>(m_inline_buffer_storage);
}
StorageType const* inline_buffer() const
{
static_assert(inline_capacity > 0);
return reinterpret_cast<StorageType const*>(m_inline_buffer_storage);
}
StorageType& raw_last() { return raw_at(size() - 1); }
StorageType& raw_first() { return raw_at(0); }
StorageType& raw_at(size_t index) { return *slot(index); }
size_t m_size { 0 };
size_t m_capacity { inline_capacity };
static constexpr size_t storage_size()
{
if constexpr (inline_capacity == 0)
return 0;
else
return sizeof(StorageType) * inline_capacity;
}
static constexpr size_t storage_alignment()
{
if constexpr (inline_capacity == 0)
return 1;
else
return alignof(StorageType);
}
alignas(storage_alignment()) unsigned char m_inline_buffer_storage[storage_size()];
StorageType* m_outline_buffer { nullptr };
};
template<class... Args>
Vector(Args... args) -> Vector<CommonType<Args...>>;
}
#if USING_AK_GLOBALLY
using AK::Vector;
#endif