Add vector and option.

1 files changed, 620 insertions, 8 deletions

diff --git a/include/fud_vector.hpp b/include/fud_vector.hpp
index 56e1659..f90819a 100644
--- a/include/fud_vector.hpp
+++ b/include/fud_vector.hpp
@@ -19,42 +19,654 @@
 #define FUD_VECTOR_HPP
 
 #include "fud_allocator.hpp"
+#include "fud_assert.hpp"
+#include "fud_config.hpp"
+#include "fud_option.hpp"
 #include "fud_result.hpp"
+#include "fud_span.hpp"
 #include "fud_status.hpp"
 
 #include <cstddef>
+#include <functional>
+#include <new> // IWYU pragma: keep (placement new)
 
 namespace fud {
 
 template <typename T>
 class Vector {
+    static constexpr size_t ElementSize = sizeof(T);
+    static constexpr size_t Alignment = alignof(T);
+
   public:
-    static Result<Vector<T>, FudStatus> from(const Vector<T>& rhs);
+    constexpr Vector() noexcept = default;
+    constexpr Vector(const Vector<T>& rhs) = delete;
+    constexpr Vector(Vector<T>&& rhs) noexcept :
+        m_allocator(rhs.m_allocator), m_data(rhs.m_data), m_length{rhs.m_length}, m_capacity{rhs.m_capacity}
+    {
+        rhs.m_allocator = nullptr;
+        rhs.m_data = nullptr;
+        rhs.m_length = 0;
+        rhs.m_capacity = 0;
+    }
+
+    ~Vector() noexcept
+    {
+        static_cast<void>(cleanup());
+    }
+
+    Vector& operator=(const Vector<T>& rhs) = delete;
+
+    Vector& operator=(Vector<T>&& rhs) noexcept
+    {
+        cleanup();
+        m_allocator = rhs.m_allocator;
+        m_data = rhs.m_data;
+        m_length = rhs.m_length;
+        m_capacity = rhs.m_length;
+
+        rhs.m_allocataor = nullptr;
+        rhs.m_data = nullptr;
+        rhs.m_length = 0;
+        rhs.m_capacity = 0;
+    }
+
+    static Result<Vector<T>, FudStatus> withCapacity(size_t capacity, Allocator* allocator = &globalFudAllocator)
+    {
+        Vector<T> output{};
+        auto status = initializeWithCapacity(output, capacity, allocator);
+        if (status != FudStatus::Success) {
+            return status;
+        }
+        return output;
+    }
+
+    static FudStatus initializeWithCapacity(
+        Vector<T>& output,
+        size_t capacity,
+        Allocator* allocator = &globalFudAllocator)
+    {
+        if (output.m_data != nullptr) {
+            return FudStatus::AlreadyInitialized;
+        }
+
+        if (allocator == nullptr) {
+            return FudStatus::NullPointer;
+        }
+
+        if (capacity > SIZE_MAX / ElementSize) {
+            return FudStatus::ArgumentInvalid;
+        }
+
+        size_t requestedSize = capacity * ElementSize;
+        auto dataPtrResult = allocator->allocate(requestedSize, Alignment);
+        if (dataPtrResult.isError()) {
+            return dataPtrResult.getError();
+        }
+
+        output.m_allocator = allocator;
+        output.m_data = static_cast<T*>(dataPtrResult.getOkay());
+        output.m_length = 0;
+        output.m_capacity = capacity;
+        return FudStatus::Success;
+    }
+
+    static Result<Vector<T>, FudStatus> withSize(size_t count, Allocator* allocator = &globalFudAllocator)
+    {
+        Vector<T> output{};
+        auto status = initializeWithCapacity(output, count, allocator);
+        if (status != FudStatus::Success) {
+            return status;
+        }
+        return output;
+    }
+
+    static Result<Vector<T>, FudStatus> initializeWithSize(
+        Vector<T>& output,
+        size_t count,
+        Allocator* allocator = &globalFudAllocator)
+    {
+        if (output.m_data != nullptr) {
+            return FudStatus::AlreadyInitialized;
+        }
+
+        auto status = Vector::initializeWithCapacity(output, count, allocator);
+        if (status != FudStatus::Success) {
+            return status;
+        }
+
+        output.m_length = count;
+        for (size_t index = 0; index < count; ++index) {
+            const auto* ptr = new (output.m_data + index) T();
+            fudAssert(ptr != nullptr);
+        }
+        return output;
+    }
+
+    template <typename Builder>
+    static Result<Vector<T>, FudStatus> withSizeFallible(
+        size_t count,
+        Builder&& builder,
+        Allocator* allocator = &globalFudAllocator)
+    {
+        Vector<T> output{};
+        auto status = initializeWithSizeFallible(output, count, std::forward<Builder>(builder), allocator);
+        if (status != FudStatus::Success) {
+            return status;
+        }
+        return output;
+    }
+
+    template <typename Builder>
+    static Result<Vector<T>, FudStatus> initializeWithSizeFallible(
+        Vector<T>& output,
+        size_t count,
+        Builder&& builder,
+        Allocator* allocator = &globalFudAllocator)
+    {
+        using BuilderResult = decltype(std::forward<Builder>(builder)());
+        static_assert(std::is_same_v<BuilderResult, FudStatus>());
+
+        auto status = Vector::initializeWithCapacity(output, count, allocator);
+        if (status != FudStatus::Success) {
+            return status;
+        }
+
+        output.m_length = count;
+
+        for (size_t index = 0; index < count; ++index) {
+            auto builderResult{std::forward<Builder>(builder)(output.m_data[index])};
+            if (builderResult.isError()) {
+                return builderResult.takeError();
+            }
+        }
+
+        return output;
+    }
 
-    static Vector<T> move(Vector<T>&& rhs);
+    static Result<Vector<T>, FudStatus> from(const Vector<T>& rhs, Option<Allocator*> allocatorOption = NullOpt)
+    {
+        Allocator* allocator = nullptr;
+        if (allocatorOption.hasValue()) {
+            allocator = allocatorOption.value();
+            if (allocator == nullptr) {
+                return FudStatus::NullPointer;
+            }
+        } else {
+            allocator = rhs.allocator;
+            if (allocator == nullptr) {
+                return FudStatus::ArgumentInvalid;
+            }
+        }
+
+        fudAssert(rhs.m_length <= rhs.m_capacity);
+
+        auto spanResult = rhs.span();
+        if (spanResult.isError()) {
+            return spanResult.takeError();
+        }
+        Vector<T> output{};
+        auto status = Vector::initializeFromSpan(output, rhs.m_length, allocator);
+        if (status != FudStatus::Success) {
+            return status;
+        }
+        return output;
+    }
+
+    template <size_t Size>
+    static Result<Vector<T>, FudStatus> from(Span<const T, Size>& rhs, Allocator* allocator)
+    {
+        Vector<T> output{};
+        auto status = initializeFromSpan(output, rhs, allocator);
+        if (status != FudStatus::Success) {
+            return status;
+        }
+        return output;
+    }
+
+    template <size_t Size>
+    static FudStatus initializeFromSpan(Vector<T>& output, Span<const T, Size>& rhs, Allocator* allocator)
+    {
+        auto status = Vector::initializeWithCapacity(output, rhs.size(), allocator);
+        if (status != FudStatus::Success) {
+            return status;
+        }
+        output.m_length = rhs.m_length;
+        for (size_t index = 0; index < output.m_length; ++index) {
+            output.m_data[index] = rhs[index];
+        }
+    }
+
+    static Vector<T> move(Vector<T>&& rhs) noexcept
+    {
+        return Vector<T>{std::move(rhs)};
+    }
 
     FudStatus copy(const Vector<T>& rhs);
 
     FudStatus take(Vector<T>&& rhs);
 
-    [[nodiscard]] size_t size() const {
+    [[nodiscard]] size_t size() const
+    {
         return m_length;
     }
 
-    [[nodiscard]] size_t capacity() const {
+    [[nodiscard]] size_t capacity() const
+    {
         return m_capacity;
     }
 
-    FudStatus reserve();
+    Result<Span<const T>, FudStatus> span() const
+    {
+        if (m_data == nullptr) {
+            return FudStatus::ObjectInvalid;
+        }
+        return Span{m_data, m_length};
+    }
+
+    Result<Span<T>, FudStatus> span()
+    {
+        if (m_data == nullptr) {
+            return FudStatus::ObjectInvalid;
+        }
+        return Span{m_data, m_length};
+    }
+
+    Result<Span<const T>, FudStatus> span(size_t count) const
+    {
+        if (m_data == nullptr) {
+            return FudStatus::ObjectInvalid;
+        }
+        if (count > m_length) {
+            return FudStatus::ArgumentInvalid;
+        }
+        return Span{m_data, count};
+    }
+
+    Result<Span<T>, FudStatus> span(size_t count)
+    {
+        if (m_data == nullptr) {
+            return FudStatus::ObjectInvalid;
+        }
+        if (count > m_length) {
+            return FudStatus::ArgumentInvalid;
+        }
+        return Span{m_data, count};
+    }
+
+    Result<Span<const T>, FudStatus> span(size_t start, size_t count) const
+    {
+        if (m_data == nullptr) {
+            return FudStatus::ObjectInvalid;
+        }
+        if (SIZE_MAX - start < m_length || start + count > m_length) {
+            return FudStatus::ArgumentInvalid;
+        }
+        return Span{m_data + start, count};
+    }
+
+    Result<Span<T>, FudStatus> span(size_t start, size_t count)
+    {
+        if (m_data == nullptr) {
+            return FudStatus::ObjectInvalid;
+        }
+        if (SIZE_MAX - start < m_length || start + count > m_length) {
+            return FudStatus::ArgumentInvalid;
+        }
+        return Span{m_data + start, count};
+    }
+
+    FudStatus reserve(size_t count)
+    {
+        if (count <= m_capacity) {
+            return FudStatus::Success;
+        }
+
+        if (m_allocator == nullptr) {
+            return FudStatus::ObjectInvalid;
+        }
+
+        if (count > SIZE_MAX / ElementSize) {
+            return FudStatus::ArgumentInvalid;
+        }
+
+        size_t requestedSize = count * ElementSize;
+        auto dataPtrResult = m_allocator->allocate(requestedSize, Alignment);
+        if (dataPtrResult.isError()) {
+            return dataPtrResult.takeError();
+        }
+
+        auto* dataPtr = static_cast<T*>(dataPtrResult.takeOkay());
+        for (size_t index = 0; index < m_length; ++index) {
+            const auto* ptr = new (dataPtr + index) T(std::move(m_data[index]));
+            fudAssert(ptr != nullptr);
+            m_data[index].~T();
+        }
+
+        m_data = dataPtr;
+        m_capacity = count;
+
+        return FudStatus::Success;
+    }
+
+    FudStatus resize(size_t count)
+    {
+        if (count == m_length) {
+            return FudStatus::Success;
+        }
+
+        if (m_allocator == nullptr) {
+            return FudStatus::ObjectInvalid;
+        }
 
-    FudStatus resize();
+        if (count < m_length) {
+            for (size_t index = count; index < m_length; ++index) {
+                m_data[index].~T();
+            }
+            m_length = count;
+            return FudStatus::Success;
+        }
 
-    FudStatus clear();
+        auto reserveStatus = reserve(count);
+        if (reserveStatus != FudStatus::Success) {
+            return reserveStatus;
+        }
 
-    // FudResult at();
+        for (size_t index = m_length; index < count; ++index) {
+            const auto* ptr = new (m_data + index) T();
+            fudAssert(ptr != nullptr);
+        }
+
+        m_length = count;
+        return FudStatus::Success;
+    }
+
+    FudStatus clear()
+    {
+        if (m_allocator == nullptr || m_data == nullptr) {
+            return FudStatus::ObjectInvalid;
+        }
+        for (size_t index = 0; index < m_length; ++index) {
+            m_data[index].~T();
+        }
+        m_length = 0;
+        return FudStatus::Success;
+    }
+
+    Result<std::reference_wrapper<T>, FudStatus> get(size_t index)
+    {
+        if (m_data == nullptr) {
+            return FudStatus::ObjectInvalid;
+        }
+        if (index >= m_length) {
+            return FudStatus::IndexInvalid;
+        }
+        return std::ref(m_data[index]);
+    }
+
+    Result<const std::reference_wrapper<const T>, FudStatus> ref(size_t index) const
+    {
+        if (m_data == nullptr) {
+            return FudStatus::ObjectInvalid;
+        }
+        if (index >= m_length) {
+            return FudStatus::IndexInvalid;
+        }
+        return std::cref(m_data[index]);
+    }
+
+    constexpr Option<T&> front()
+    {
+        if (m_length > 0) {
+            fudAssert(m_data != nullptr);
+            return m_data[0];
+        }
+        return NullOpt;
+    }
+
+    constexpr Option<const T&> front() const
+    {
+        if (m_length > 0) {
+            fudAssert(m_data != nullptr);
+            return m_data[0];
+        }
+        return NullOpt;
+    }
+
+    constexpr Option<T&> back()
+    {
+        if (m_length > 0) {
+            fudAssert(m_data != nullptr);
+            return m_data[m_length - 1];
+        }
+        return NullOpt;
+    }
+
+    constexpr Option<const T&> back() const
+    {
+        if (m_length > 0) {
+            return m_data[m_length - 1];
+        }
+        return NullOpt;
+    }
+
+    constexpr T* data() noexcept
+    {
+        return m_data;
+    }
+
+    constexpr const T* data() const noexcept
+    {
+        return m_data;
+    }
+
+    constexpr T* begin() noexcept
+    {
+        return m_data;
+    }
+
+    constexpr const T* begin() const noexcept
+    {
+        return m_data;
+    }
+
+    constexpr T* end() noexcept
+    {
+        return m_data + m_length;
+    }
+
+    constexpr const T* end() const noexcept
+    {
+        return m_data + m_length;
+    }
+
+    constexpr T& operator[](size_t index)
+    {
+        if constexpr (fudBoundsChecking) {
+            fudAssert(m_data != nullptr);
+            fudAssert(index < m_length);
+        }
+        return m_data[index];
+    }
+
+    constexpr const T& operator[](size_t index) const
+    {
+        if constexpr (fudBoundsChecking) {
+            fudAssert(m_data != nullptr);
+            fudAssert(index < m_length);
+        }
+        return m_data[index];
+    }
+
+    FudStatus pushBack(const T& value)
+    {
+        if (m_length == m_capacity) {
+            auto status = grow();
+            if (status != FudStatus::Success) {
+                return status;
+            }
+        }
+        const auto* ptr = new (m_data + m_length) T(value);
+        fudAssert(ptr != nullptr);
+        m_length++;
+        return FudStatus::Success;
+    }
+
+    FudStatus pushBack(T&& value)
+    {
+        if (m_length == m_capacity) {
+            auto status = grow();
+            if (status != FudStatus::Success) {
+                return status;
+            }
+        }
+        const auto* ptr = new (m_data + m_length) T(std::move(value));
+        fudAssert(ptr != nullptr);
+        m_length++;
+        return FudStatus::Success;
+    }
+
+    Result<T, FudStatus> popBack()
+    {
+        if (m_data == nullptr) {
+            return FudStatus::ObjectInvalid;
+        }
+        if (m_length == 0) {
+            return FudStatus::Empty;
+        }
+        auto result{std::move(m_data[m_length - 1])};
+        m_length--;
+        m_data[m_length].~T();
+        return result;
+    }
+
+    FudStatus eraseBack()
+    {
+        if (m_data == nullptr) {
+            return FudStatus::ObjectInvalid;
+        }
+        if (m_length == 0) {
+            return FudStatus::Empty;
+        }
+        m_length--;
+        m_data[m_length].~T();
+        return FudStatus::Success;
+    }
+
+    FudStatus insert(size_t index, const T& value)
+    {
+        if (index > m_length) {
+            return FudStatus::IndexInvalid;
+        }
+        if (index == m_length) {
+            return pushBack(value);
+        }
+        if (m_length == m_capacity) {
+            auto status = grow();
+            if (status != FudStatus::Success) {
+                return status;
+            }
+        }
+
+        const auto* ptr = new (m_data + m_length) T(std::move(m_data[m_length - 1]));
+        fudAssert(ptr != nullptr);
+
+        for (size_t backIndex = m_length - 1; backIndex > index; --backIndex) {
+            m_data[backIndex] = std::move(m_data[backIndex - 1]);
+        }
+        m_data[index] = value;
+        m_length++;
+        return FudStatus::Success;
+    }
+
+    FudStatus insert(size_t index, T&& value)
+    {
+        if (index > m_length) {
+            return FudStatus::IndexInvalid;
+        }
+        if (index == m_length) {
+            return pushBack(std::move(value));
+        }
+        if (m_length == m_capacity) {
+            auto status = grow();
+            if (status != FudStatus::Success) {
+                return status;
+            }
+        }
+
+        const auto* ptr = new (m_data + m_length) T(std::move(m_data[m_length - 1]));
+        fudAssert(ptr != nullptr);
+
+        for (size_t backIndex = m_length - 1; backIndex > index; --backIndex) {
+            m_data[backIndex] = std::move(m_data[backIndex - 1]);
+        }
+        m_data[index] = std::move(value);
+        m_length++;
+        return FudStatus::Success;
+    }
+
+    FudStatus erase(size_t index)
+    {
+        if (index >= m_length) {
+            return FudStatus::IndexInvalid;
+        }
+
+        m_data[index].~T();
+        for (size_t fwdIndex = index; fwdIndex + 1 < m_length; fwdIndex++)
+        {
+            m_data[fwdIndex] = std::move(m_data[fwdIndex + 1]);
+        }
+        m_data[m_length - 1].~T();
+        m_length--;
+        return FudStatus::Success;
+    }
 
   private:
+    FudStatus grow()
+    {
+        // See https://github.com/facebook/folly/blob/main/folly/docs/FBVector.md
+        size_t additional = m_capacity < 2 ? 1 : m_capacity / 2;
+        if (SIZE_MAX - additional * ElementSize < m_capacity * ElementSize) {
+            additional = SIZE_MAX - m_capacity * ElementSize / 2;
+        }
+        while (additional > 0) {
+            auto reserveStatus = reserve(additional + m_capacity);
+            if (reserveStatus == FudStatus::Success) {
+                break;
+            }
+            if (reserveStatus == FudStatus::AllocFailure) {
+                additional /= 2;
+            } else {
+                return reserveStatus;
+            }
+        }
+
+        if (m_length == m_capacity) {
+            return FudStatus::AllocFailure;
+        }
+
+        return FudStatus::Success;
+    }
+
+    FudStatus cleanup() noexcept
+    {
+        auto status = clear();
+
+        if (m_data != nullptr && m_allocator != nullptr) {
+            auto deallocStatus = m_allocator->deallocate(m_data, m_capacity);
+            if (status == FudStatus::Success) {
+                status = deallocStatus;
+            }
+        }
+
+        m_allocator = nullptr;
+        m_data = nullptr;
+        m_length = 0;
+        m_capacity = 0;
+        return status;
+    }
+
     Allocator* m_allocator{&globalFudAllocator};
+    T* m_data{nullptr};
     size_t m_length{0};
     size_t m_capacity{0};
 };