diff options
Diffstat (limited to 'libs/kstd/include')
| -rw-r--r-- | libs/kstd/include/kstd/bits/os.hpp | 13 | ||||
| -rw-r--r-- | libs/kstd/include/kstd/vector.hpp | 596 |
2 files changed, 609 insertions, 0 deletions
diff --git a/libs/kstd/include/kstd/bits/os.hpp b/libs/kstd/include/kstd/bits/os.hpp new file mode 100644 index 0000000..0425b88 --- /dev/null +++ b/libs/kstd/include/kstd/bits/os.hpp @@ -0,0 +1,13 @@ +#ifndef KSTD_OS_HPP +#define KSTD_OS_HPP + +#include <source_location> +#include <string_view> + +namespace kstd::os +{ + [[noreturn]] + auto panic(std::string_view message, std::source_location = std::source_location::current()) -> void; +} + +#endif
\ No newline at end of file diff --git a/libs/kstd/include/kstd/vector.hpp b/libs/kstd/include/kstd/vector.hpp new file mode 100644 index 0000000..1009e81 --- /dev/null +++ b/libs/kstd/include/kstd/vector.hpp @@ -0,0 +1,596 @@ +#ifndef KSTD_VECTOR_HPP +#define KSTD_VECTOR_HPP + +#include "bits/os.hpp" + +#include <algorithm> + +namespace kstd +{ + /** + * @brief Custom vector implementation mirroring the std::vector to allow for the usage of STL functionality with our + * custom memory management. + * + * @tparam T Element the vector instance should contain. + */ + template<typename T> + struct vector + { + using value_type = T; ///< Type of the elements contained in the container. + using size_type = std::size_t; ///< Type of the size in the container. + using reference = value_type &; ///< Type of reference to the elements. + using const_reference = value_type const &; ///< Type of constant reference to the elements. + using pointer = value_type *; ///< Type of pointer to the elements. + using const_pointer = value_type const *; ///< Type of constant pointer to the elements. + + /** + * @brief Default Constructor. + */ + vector() = default; + + /** + * @brief Constructs data with the given amount of elements containg the given value or alterantively the default + * constructed value. + * + * @param n Amount of elements we want to create and set the given value for. + * @param initial Inital value of all elements in the underlying data array. + */ + explicit vector(size_type n, value_type initial = value_type{}) + : _size(n) + , _capacity(n) + , _data(new value_type[_capacity]{}) + { + std::ranges::fill(*this, initial); + } + + /** + * @brief Constructs data by copying all element from the given exclusive range. + * + * @tparam InputIterator Template that should have atleast input iterator characteristics. + * @param first Input iterator to the first element in the range we want to copy from. + * @param last Input iterator to one past the last element in the range we want to copy from. + */ + template<typename InputIterator> + explicit vector(InputIterator first, InputIterator last) + : _size(std::distance(first, last)) + , _capacity(std::distance(first, last)) + , _data(new value_type[_capacity]{}) + { + std::ranges::copy(first, last, _data); + } + + /** + * @brief Construct data by copying all elements from the initializer list. + * + * @param initalizer_list List we want to copy all elements from. + */ + explicit vector(std::initializer_list<value_type> initalizer_list) + : _size(initalizer_list.size()) + , _capacity(initalizer_list.size()) + , _data(new value_type[_capacity]{}) + { + std::ranges::copy(initalizer_list, _data); + } + + /** + * @brief Copy constructor. + * + * @note Allocates underlying data container with the same capacity as vector we are copying from and copies all + * elements from it. + * + * @param other Other instance of vector we want to copy the data from. + */ + vector(vector<value_type> const & other) + : _size(other._size) + , _capacity(other._capacity) + { + delete[] _data; + _data = new value_type[_capacity]{}; + std::ranges::copy(other, _data); + } + + /** + * @brief Copy assignment operator. + * + * @note Allocates underlying data container with the same capacity as vector we are copying from and copies all + * elements from it. + * + * @param other Other instance of vector we want to copy the data from. + * @return Newly created copy. + */ + [[gnu::section(".stl_text")]] + vector<value_type> & operator=(vector<value_type> const & other) + { + delete[] _data; + _size = other._size; + _capacity = other._capacity; + _data = new value_type[_capacity]{}; + std::ranges::copy(other, _data); + return *this; + } + + /** + * @brief Destructor. + */ + ~vector() { delete[] _data; } + + /** + * @brief Amount of elements currently contained in this vector, will fill up until we have reached the capacity. If + * that is the case the capacity is increased automatically. + * + * @return Current amount of elements. + */ + [[gnu::section(".stl_text")]] + auto size() const -> size_type + { + return _size; + } + + /** + * @brief Amount of space the vector currently has, can be different than the size, because we allocate more than we + * exactly require to decrease the amount of allocations and deallocation to improve speed. + * + * @return Current amount of space the vector has for elements. + */ + [[gnu::section(".stl_text")]] + auto capacity() const -> size_type + { + return _capacity; + } + + /** + * @brief Array indexing operator. Allowing to access element at the given index. + * + * @note Does not do any bounds checks use at() for that. + * + * @param index Index we want to access elements at. + * @return Reference to the underlying element. + */ + [[gnu::section(".stl_text")]] + auto operator[](size_type index) -> reference + { + return _data[index]; + } + + /** + * @brief Array indexing operator. Allowing to access element at the given index. + * + * @note Does not do any bounds checks use at() for that. + * + * @param index Index we want to access elements at. + * @return Reference to the underlying element. + */ + [[gnu::section(".stl_text")]] + auto operator[](size_type index) const -> const_reference + { + return _data[index]; + } + + /** + * @brief Array indexing operator. Allowing to access element at the given index. + * + * @note Ensures we do not access element outside of the bounds of the array, if we do further execution is halted. + * + * @param index Index we want to access elements at. + * @return Reference to the underlying element. + */ + [[gnu::section(".stl_text")]] + auto at(size_type index) -> reference + { + throw_if_out_of_range(index); + return this->operator[](index); + } + + /** + * @brief Array indexing operator. Allowing to access element at the given index. + * + * @note Ensures we do not access element outside of the bounds of the array, if we do further execution is halted. + * + * @param index Index we want to access elements at. + * @return Reference to the underlying element. + */ + [[gnu::section(".stl_text")]] + auto at(size_type index) const -> const_reference + { + throw_if_out_of_range(index); + return this->operator[](index); + } + + /** + * @brief Appends the given element value to the end of the container. The element is assigned through the + * assignment operator of the template type. The value is forwarded to the constructor as + * std::forward<U>(value), meaning it is either moved (rvalue) or copied (lvalue). + * + * @note If after the operation the new size() is greater than old capacity() a reallocation takes place, + * in which case all iterators (including the end() iterator) and all references to the elements are invalidated. + * Otherwise only the end() iterator is invalidated. Uses a forward reference for the actual value passed, which + * allows the template method to be used by both lvalue and rvalues and compile a different implementation. + * + * @param value The value of the element to append. + */ + template<class U> + [[gnu::section(".stl_text")]] + auto push_back(U && value) -> void + { + increase_capacity_if_full(); + _data[_size] = std::forward<U>(value); + (void)_size++; + } + + /** + * @brief Appends a new element to the end of the container. The element is constructed through a constructor of the + * template type. The arguments args... are forwarded to the constructor as std::forward<Args>(args).... + * + * If after the operation the new size() is greater than old capacity() a reallocation takes place, in which case + * all iterators (including the end() iterator) and all references to the elements are invalidated. Otherwise only + * the end() iterator is invalidated. Uses a forward reference for the actual value passed, which + * allows the template method to be used by both lvalue and rvalues and compile a different implementation. + * + * @tparam Args + * @param args Arguments to forward to the constructor of the element + * @return value_type& + */ + template<class... Args> + [[gnu::section(".stl_text")]] + auto emplace_back(Args &&... args) -> value_type & + { + increase_capacity_if_full(); + _data[_size] = value_type{std::forward<Args>(args)...}; + auto const index = _size++; + return _data[index]; + } + + /** + * @brief Removes the last element of the container. Calling pop_back on an empty container results in halting the + * further execution. Iterators and references to the last element are invalidated. The end() + * iterator is also invalidated. + */ + [[gnu::section(".stl_text")]] + auto pop_back() -> void + { + throw_if_empty(); + (void)_size--; + } + + /** + * @brief Returns an iterator to the first element of the vector. + * If the vector is empty, the returned iterator will be equal to end(). + * + * @return Iterator to the first element. + */ + [[gnu::section(".stl_text")]] + auto begin() noexcept -> pointer + { + return _data; + } + + /** + * @brief Returns an iterator to the first element of the vector. + * If the vector is empty, the returned iterator will be equal to end(). + * + * @return Iterator to the first element. + */ + [[gnu::section(".stl_text")]] + auto begin() const noexcept -> const_pointer + { + return _data; + } + + /** + * @brief Returns an iterator to the first element of the vector. + * If the vector is empty, the returned iterator will be equal to end(). + * + * @return Iterator to the first element. + */ + [[gnu::section(".stl_text")]] + auto cbegin() const noexcept -> const_pointer + { + return begin(); + } + + /** + * @brief Returns a reverse iterator to the first element of the reversed vector. It corresponds to the last element + * of the non-reversed vector. If the vector is empty, the returned iterator will be equal to rend(). + * + * @return Reverse iterator to the first element. + */ + [[gnu::section(".stl_text")]] + auto rbegin() noexcept -> pointer + { + return _data + _size - 1; + } + + /** + * @brief Returns a reverse iterator to the first element of the reversed vector. It corresponds to the last element + * of the non-reversed vector. If the vector is empty, the returned iterator will be equal to rend(). + * + * @return Reverse iterator to the first element. + */ + [[gnu::section(".stl_text")]] + auto rbegin() const noexcept -> const_pointer + { + return _data + _size - 1; + } + + /** + * @brief Returns a reverse iterator to the first element of the reversed vector. It corresponds to the last element + * of the non-reversed vector. If the vector is empty, the returned iterator will be equal to rend(). + * + * @return Reverse iterator to the first element. + */ + [[gnu::section(".stl_text")]] + auto crbegin() const noexcept -> const_pointer + { + return rbegin(); + } + + /** + * @brief Returns an iterator to the element following the last element of the vector. This element acts as a + * placeholder, attempting to access it results in undefined behavior. + * + * @return Iterator to the element following the last element. + */ + [[gnu::section(".stl_text")]] + auto end() noexcept -> pointer + { + return _data + _size; + } + + /** + * @brief Returns an iterator to the element following the last element of the vector. This element acts as a + * placeholder, attempting to access it results in undefined behavior. + * + * @return Iterator to the element following the last element. + */ + [[gnu::section(".stl_text")]] + auto end() const noexcept -> const_pointer + { + return _data + _size; + } + + /** + * @brief Returns an iterator to the element following the last element of the vector. This element acts as a + * placeholder, attempting to access it results in undefined behavior. + * + * @return Iterator to the element following the last element. + */ + [[gnu::section(".stl_text")]] + auto cend() const noexcept -> const_pointer + { + return end(); + } + + /** + * @brief Returns a reverse iterator to the element following the last element of the reversed vector. It + * corresponds to the element preceding the first element of the non-reversed vector. This element acts as a + * placeholder, attempting to access it results in undefined behavior. + * + * @return Reverse iterator to the element following the last element. + */ + [[gnu::section(".stl_text")]] + auto rend() noexcept -> pointer + { + return _data + size() - 1; + } + + /** + * @brief Returns a reverse iterator to the element following the last element of the reversed vector. It + * corresponds to the element preceding the first element of the non-reversed vector. This element acts as a + * placeholder, attempting to access it results in undefined behavior. + * + * @return Reverse iterator to the element following the last element. + */ + [[gnu::section(".stl_text")]] + auto rend() const noexcept -> const_pointer + { + return _data + size() - 1; + } + + /** + * @brief Returns a reverse iterator to the element following the last element of the reversed vector. It + * corresponds to the element preceding the first element of the non-reversed vector. This element acts as a + * placeholder, attempting to access it results in undefined behavior. + * + * @return Reverse iterator to the element following the last element. + */ + [[gnu::section(".stl_text")]] + auto crend() const noexcept -> const_pointer + { + return rbegin(); + } + + /** + * @brief Returns a pointer to the underlying array serving as element storage. The pointer is such that range + * [data(), data() + size()) is always a valid range, even if the container is empty (data() is not dereferenceable + * in that case). + * + * @return Pointer to the underlying element storage. For non-empty containers, the returned pointer compares equal + * to the address of the first element. + */ + [[gnu::section(".stl_text")]] + auto data() -> pointer + { + return _data; + } + + /** + * @brief Returns a pointer to the underlying array serving as element storage. The pointer is such that range + * [data(), data() + size()) is always a valid range, even if the container is empty (data() is not dereferenceable + * in that case). + * + * @return Pointer to the underlying element storage. For non-empty containers, the returned pointer compares equal + * to the address of the first element. + */ + [[gnu::section(".stl_text")]] + auto data() const -> const_pointer + { + return _data; + } + + /** + * @brief Returns a reference to the first element in the container. Calling front on an empty container causes + * undefined behavior. + * + * @return Reference to the first element. + */ + [[gnu::section(".stl_text")]] + auto front() -> reference + { + throw_if_empty(); + return *begin(); + } + + /** + * @brief Returns a reference to the first element in the container. Calling front on an empty container causes + * undefined behavior. + * + * @return Reference to the first element. + */ + [[gnu::section(".stl_text")]] + auto front() const -> const_reference + { + throw_if_empty(); + return *begin(); + } + + /** + * @brief Returns a reference to the last element in the container. Calling back on an empty container causes + * undefined behavior. + * + * @return Reference to the last element. + */ + [[gnu::section(".stl_text")]] + auto back() -> reference + { + throw_if_empty(); + return *rbegin(); + } + + /** + * @brief Returns a reference to the last element in the container. Calling back on an empty container causes + * undefined behavior. + * + * @return Reference to the last element. + */ + [[gnu::section(".stl_text")]] + auto back() const -> const_reference + { + throw_if_empty(); + return *rbegin(); + } + + /** + * @brief Increase the capacity of the vector (the total number of elements that the vector can hold without + * requiring reallocation) to a value that's greater or equal to new_cap. If new_cap is greater than the current + * capacity(), new storage is allocated, otherwise the function does nothing. + * + * reserve() does not change the size of the vector. + * + * If new_cap is greater than capacity(), all iterators (including the end() iterator) and all references to the + * elements are invalidated. Otherwise, no iterators or references are invalidated. + * + * After a call to reserve(), insertions will not trigger reallocation unless the insertion would make the size of + * the vector greater than the value of capacity(). + * + * @note Correctly using reserve() can prevent unnecessary reallocations, but inappropriate uses of reserve() (for + * instance, calling it before every push_back() call) may actually increase the number of reallocations (by causing + * the capacity to grow linearly rather than exponentially) and result in increased computational complexity and + * decreased performance. For example, a function that receives an arbitrary vector by reference and appends + * elements to it should usually not call reserve() on the vector, since it does not know of the vector's usage + * characteristics. + * + * When inserting a range, the range version of insert() is generally preferable as it preserves the correct + * capacity growth behavior, unlike reserve() followed by a series of push_back()s. + * + * reserve() cannot be used to reduce the capacity of the container; to that end shrink_to_fit() is provided. + * + * @param new_capacity New capacity of the vector, in number of elements + */ + [[gnu::section(".stl_text")]] + auto reserve(size_type new_capacity) -> void + { + if (new_capacity <= _capacity) + { + return; + } + + _capacity = new_capacity; + value_type * temp = new value_type[_capacity]{}; + std::ranges::copy(begin(), end(), temp); + delete[] _data; + _data = temp; + } + + /** + * @brief Requests the removal of unused capacity. Meaning it requests to reduce capacity() to size(). + * + * If reallocation occurs, all iterators (including the end() iterator) and all references to the elements are + * invalidated. If no reallocation occurs, no iterators or references are invalidated. + */ + [[gnu::section(".stl_text")]] + auto shrink_to_fit() -> void + { + if (_size == _capacity) + { + return; + } + + _capacity = _size; + value_type * temp = new value_type[_capacity]{}; + std::ranges::copy(begin(), end(), temp); + delete[] _data; + _data = temp; + } + + /** + * @brief Wheter there are currently any items this container or not. + * + * @return True if there are no elements, false if there are. + */ + [[gnu::section(".stl_text")]] + auto empty() const -> bool + { + return _size <= 0; + } + + private: + /** + * @brief Halts the execution of the application if the data container is currently empty. + */ + auto throw_if_empty() const -> void + { + if (empty()) + { + os::panic("[Vector] Attempted to access element of currently empty vector"); + } + } + + auto throw_if_out_of_range(size_type index) const -> void + { + if (index >= _size) + { + os::panic("[Vector] Attempted to read element at invalid index"); + } + } + + /** + * @brief Increases the internal capacity to 1 if it was previously 0 and to * 2 after that, meaning exponential + * growth. This is done to decrease the amount of single allocations done and because a power of 2 in memory size is + * normally perferable for the cache. + */ + auto increase_capacity_if_full() -> void + { + if (_size == _capacity) + { + reserve(_capacity == 0U ? 1U : _capacity * 2U); + } + } + + size_type _size = {}; ///< Amount of elements in the underlying data container + size_type _capacity = {}; ///< Amount of space for elements in the underlying data container + value_type * _data = {}; ///< Pointer to the first element in the underlying data container + }; + +} // namespace kstd + +#endif |