BLT/include/blt/std/memory.h

618 lines
19 KiB
C++

/*
* Created by Brett on 08/02/23.
* Licensed under GNU General Public License V3.0
* See LICENSE file for license detail
*/
#ifndef BLT_TESTS_MEMORY_H
#define BLT_TESTS_MEMORY_H
#include <blt/std/memory_util.h>
#include <initializer_list>
#include <iterator>
#include <cstring>
#include "queue.h"
#include "utility.h"
#include <blt/std/assert.h>
#include <cstdint>
#include <type_traits>
#include <utility>
#include <cstring>
namespace blt
{
template<typename T, bool = std::is_copy_constructible_v<T> || std::is_copy_assignable_v<T>>
class scoped_buffer;
/**
* Creates an encapsulation of a T array which will be automatically deleted when this object goes out of scope.
* This is a simple buffer meant to be used only inside of a function and not copied around.
* The internal buffer is allocated on the heap.
* The operator * has been overloaded to return the internal buffer.
* @tparam T type that is stored in buffer eg char
*/
template<typename T>
class scoped_buffer<T, true>
{
public:
using element_type = T;
using value_type = std::remove_cv_t<T>;
using pointer = T*;
using const_pointer = const T*;
using reference = T&;
using const_reference = const T&;
using iterator = ptr_iterator<T>;
using const_iterator = ptr_iterator<const T>;
using reverse_iterator = std::reverse_iterator<iterator>;
using const_reverse_iterator = std::reverse_iterator<const_iterator>;
private:
T* buffer_ = nullptr;
size_t size_;
public:
constexpr scoped_buffer(): buffer_(nullptr), size_(0)
{}
constexpr explicit scoped_buffer(size_t size): size_(size)
{
if (size > 0)
buffer_ = new T[size];
else
buffer_ = nullptr;
}
constexpr scoped_buffer(const scoped_buffer& copy)
{
if (copy.size() == 0)
{
buffer_ = nullptr;
size_ = 0;
return;
}
buffer_ = new T[copy.size()];
size_ = copy.size_;
if constexpr (std::is_trivially_copyable_v<T>)
{
std::memcpy(buffer_, copy.buffer_, copy.size() * sizeof(T));
} else
{
if constexpr (std::is_copy_constructible_v<T> && !std::is_copy_assignable_v<T>)
{
for (size_t i = 0; i < this->size_; i++)
buffer_[i] = T(copy[i]);
} else
for (size_t i = 0; i < this->size_; i++)
buffer_[i] = copy[i];
}
}
constexpr scoped_buffer& operator=(const scoped_buffer& copy)
{
if (&copy == this)
return *this;
if (copy.size() == 0)
{
buffer_ = nullptr;
size_ = 0;
return *this;
}
delete[] this->buffer_;
buffer_ = new T[copy.size()];
size_ = copy.size_;
if constexpr (std::is_trivially_copyable_v<T>)
{
std::memcpy(buffer_, copy.buffer_, copy.size() * sizeof(T));
} else
{
if constexpr (std::is_copy_constructible_v<T> && !std::is_copy_assignable_v<T>)
{
for (size_t i = 0; i < this->size_; i++)
buffer_[i] = T(copy[i]);
} else
for (size_t i = 0; i < this->size_; i++)
buffer_[i] = copy[i];
}
return *this;
}
constexpr scoped_buffer(scoped_buffer&& move) noexcept
{
delete[] buffer_;
buffer_ = move.buffer_;
size_ = move.size();
move.buffer_ = nullptr;
}
constexpr scoped_buffer& operator=(scoped_buffer&& moveAssignment) noexcept
{
delete[] buffer_;
buffer_ = moveAssignment.buffer_;
size_ = moveAssignment.size();
moveAssignment.buffer_ = nullptr;
return *this;
}
/**
* Resize the internal buffer. Nothing will occur if the sizes are equal.
* This function WILL NOT COPY ANY DATA. It is meant for use when creating a scoped buffer without size.
*/
constexpr void resize(size_t size)
{
if (size == 0)
return;
if (size == size_)
return;
delete[] buffer_;
buffer_ = new T[size];
size_ = size;
}
constexpr inline T& operator[](size_t index)
{
return buffer_[index];
}
constexpr inline const T& operator[](size_t index) const
{
return buffer_[index];
}
constexpr inline T* operator*()
{
return buffer_;
}
[[nodiscard]] constexpr inline size_t size() const
{
return size_;
}
constexpr inline T*& ptr()
{
return buffer_;
}
constexpr inline const T* const& ptr() const
{
return buffer_;
}
constexpr inline const T* const& data() const
{
return buffer_;
}
constexpr inline T*& data()
{
return buffer_;
}
constexpr iterator begin() noexcept
{
return iterator{data()};
}
constexpr iterator end() noexcept
{
return iterator{data() + size()};
}
constexpr const_iterator cbegin() const noexcept
{
return const_iterator{data()};
}
constexpr const_iterator cend() const noexcept
{
return const_iterator{data() + size()};
}
constexpr inline reverse_iterator rbegin() noexcept
{
return reverse_iterator{end()};
}
constexpr inline reverse_iterator rend() noexcept
{
return reverse_iterator{begin()};
}
constexpr inline const_iterator crbegin() const noexcept
{
return const_reverse_iterator{cend()};
}
constexpr inline reverse_iterator crend() const noexcept
{
return reverse_iterator{cbegin()};
}
~scoped_buffer()
{
delete[] buffer_;
}
};
template<typename T>
class scoped_buffer<T, false> : scoped_buffer<T, true>
{
using scoped_buffer<T, true>::scoped_buffer;
public:
scoped_buffer(const scoped_buffer& copy) = delete;
scoped_buffer operator=(scoped_buffer& copyAssignment) = delete;
};
// TODO: might already have a version of this somewhere!
template<typename T, bool = std::is_copy_constructible_v<T> || std::is_copy_assignable_v<T>>
class expanding_buffer;
template<typename T>
class expanding_buffer<T, true>
{
public:
using element_type = T;
using value_type = std::remove_cv_t<T>;
using pointer = T*;
using const_pointer = const T*;
using reference = T&;
using const_reference = const T&;
using iterator = ptr_iterator<T>;
using const_iterator = ptr_iterator<const T>;
using reverse_iterator = std::reverse_iterator<iterator>;
using const_reverse_iterator = std::reverse_iterator<const_iterator>;
private:
T* buffer_ = nullptr;
size_t size_ = 0;
public:
constexpr expanding_buffer(): buffer_(nullptr), size_(0)
{}
constexpr explicit expanding_buffer(size_t size): size_(size)
{
if (size > 0)
buffer_ = new T[size];
else
buffer_ = nullptr;
}
constexpr expanding_buffer(const expanding_buffer& copy)
{
if (copy.size() == 0)
{
buffer_ = nullptr;
size_ = 0;
return;
}
buffer_ = new T[copy.size()];
size_ = copy.size_;
if constexpr (std::is_trivially_copyable_v<T>)
{
std::memcpy(buffer_, copy.buffer_, copy.size() * sizeof(T));
} else
{
if constexpr (std::is_copy_constructible_v<T> && !std::is_copy_assignable_v<T>)
{
for (size_t i = 0; i < this->size_; i++)
buffer_[i] = T(copy[i]);
} else
for (size_t i = 0; i < this->size_; i++)
buffer_[i] = copy[i];
}
}
constexpr expanding_buffer& operator=(const expanding_buffer& copy)
{
if (&copy == this)
return *this;
if (copy.size() == 0)
{
buffer_ = nullptr;
size_ = 0;
return *this;
}
delete_this(buffer_, size());
buffer_ = new T[copy.size()];
size_ = copy.size_;
if constexpr (std::is_trivially_copyable_v<T>)
{
std::memcpy(buffer_, copy.buffer_, copy.size() * sizeof(T));
} else
{
if constexpr (std::is_copy_constructible_v<T> && !std::is_copy_assignable_v<T>)
{
for (size_t i = 0; i < this->size_; i++)
buffer_[i] = T(copy[i]);
} else
for (size_t i = 0; i < this->size_; i++)
buffer_[i] = copy[i];
}
return *this;
}
constexpr expanding_buffer(expanding_buffer&& move) noexcept
{
delete_this(buffer_, size());
buffer_ = move.buffer_;
size_ = move.size();
move.buffer_ = nullptr;
}
constexpr expanding_buffer& operator=(expanding_buffer&& moveAssignment) noexcept
{
delete_this(buffer_, size());
buffer_ = moveAssignment.buffer_;
size_ = moveAssignment.size();
moveAssignment.buffer_ = nullptr;
return *this;
}
/**
* Resize the internal buffer. Nothing will occur if the sizes are equal.
* This function WILL NOT COPY ANY DATA. It is meant for use when creating a scoped buffer without size.
*/
constexpr void resize(size_t size)
{
if (size == 0)
return;
if (size == size_)
return;
delete_this(buffer_, this->size());
buffer_ = new T[size];
size_ = size;
}
constexpr inline T& operator[](size_t index)
{
if (index >= size())
allocate_for(index);
return buffer_[index];
}
constexpr inline const T& operator[](size_t index) const
{
if (index >= size())
allocate_for(index);
return buffer_[index];
}
constexpr inline T* operator*()
{
return buffer_;
}
[[nodiscard]] constexpr inline size_t size() const
{
return size_;
}
constexpr inline T*& ptr()
{
return buffer_;
}
constexpr inline const T* const& ptr() const
{
return buffer_;
}
constexpr inline const T* const& data() const
{
return buffer_;
}
constexpr inline T*& data()
{
return buffer_;
}
constexpr iterator begin() noexcept
{
return iterator{data()};
}
constexpr iterator end() noexcept
{
return iterator{data() + size()};
}
constexpr const_iterator cbegin() const noexcept
{
return const_iterator{data()};
}
constexpr const_iterator cend() const noexcept
{
return const_iterator{data() + size()};
}
constexpr inline reverse_iterator rbegin() noexcept
{
return reverse_iterator{end()};
}
constexpr inline reverse_iterator rend() noexcept
{
return reverse_iterator{begin()};
}
constexpr inline const_iterator crbegin() const noexcept
{
return const_reverse_iterator{cend()};
}
constexpr inline reverse_iterator crend() const noexcept
{
return reverse_iterator{cbegin()};
}
~expanding_buffer()
{
delete_this(buffer_, size());
}
void expand(blt::size_t new_size)
{
T* new_buffer = new T[new_size];
if (buffer_ != nullptr)
{
if constexpr (std::is_trivially_copyable_v<T>)
{
std::memcpy(new_buffer, buffer_, size_ * sizeof(T));
} else
{
if constexpr (std::is_copy_constructible_v<T> && !std::is_move_constructible_v<T>)
{
for (size_t i = 0; i < size_; i++)
new_buffer[i] = T(buffer_[i]);
} else
for (size_t i = 0; i < size_; i++)
new_buffer[i] = std::move(buffer_[i]);
}
delete[] buffer_;
}
buffer_ = new_buffer;
size_ = new_size;
}
private:
void allocate_for(blt::size_t accessing_index)
{
accessing_index = std::max(size_, accessing_index);
accessing_index = blt::mem::next_byte_allocation(accessing_index);
expand(accessing_index);
}
inline void delete_this(T* buffer, blt::size_t)
{
// if constexpr (std::is_trivially_destructible_v<T>)
// return;
// if (buffer == nullptr)
// return;
// for (blt::size_t i = 0; i < size; i++)
// buffer[i]->~T();
// free(buffer);
delete[] buffer;
}
};
template<typename T>
class expanding_buffer<T, false> : expanding_buffer<T, true>
{
using expanding_buffer<T, true>::expanding_buffer;
public:
expanding_buffer(const expanding_buffer& copy) = delete;
expanding_buffer operator=(expanding_buffer& copyAssignment) = delete;
};
template<typename T>
struct nullptr_initializer
{
private:
T* m_ptr = nullptr;
public:
nullptr_initializer() = default;
explicit nullptr_initializer(T* ptr): m_ptr(ptr)
{}
nullptr_initializer(const nullptr_initializer<T>& ptr): m_ptr(ptr.m_ptr)
{}
nullptr_initializer(nullptr_initializer<T>&& ptr) noexcept: m_ptr(ptr.m_ptr)
{}
nullptr_initializer<T>& operator=(const nullptr_initializer<T>& ptr)
{
if (&ptr == this)
return *this;
this->m_ptr = ptr.m_ptr;
return *this;
}
nullptr_initializer<T>& operator=(nullptr_initializer<T>&& ptr) noexcept
{
if (&ptr == this)
return *this;
this->m_ptr = ptr.m_ptr;
return *this;
}
inline T* operator->()
{
return m_ptr;
}
~nullptr_initializer() = default;
};
/**
* Creates a hash-map like association between an enum key and any arbitrary value.
* The storage is backed by a contiguous array for faster access.
* @tparam K enum value
* @tparam V associated value
*/
template<typename K, typename V>
class enum_storage
{
private:
V* m_values;
size_t m_size = 0;
public:
enum_storage(std::initializer_list<std::pair<K, V>> init)
{
for (auto& i : init)
m_size = std::max((size_t) i.first, m_size);
m_values = new V[m_size];
for (auto& v : init)
m_values[(size_t) v.first] = v.second;
}
inline V& operator[](size_t index)
{
return m_values[index];
}
inline const V& operator[](size_t index) const
{
return m_values[index];
}
[[nodiscard]] inline size_t size() const
{
return m_size;
}
ptr_iterator<V> begin()
{
return ptr_iterator{m_values};
}
ptr_iterator<V> end()
{
return ptr_iterator{&m_values[m_size]};
}
~enum_storage()
{
delete[] m_values;
}
};
}
#endif //BLT_TESTS_MEMORY_H