ArrayReference.h   [plain text]

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#pragma once

#include <limits>
#include <wtf/Vector.h>

namespace IPC {

inline constexpr size_t arrayReferenceDynamicExtent = std::numeric_limits<size_t>::max();

template <typename T, size_t Extent = arrayReferenceDynamicExtent>
class ArrayReference;

template <typename T>
class ArrayReference<T, arrayReferenceDynamicExtent> {
public:
    ArrayReference() = default;

    ArrayReference(const T* data, size_t size)
        : m_data(data)
        , m_size(size)
    {
    }

    template <size_t inlineCapacity>
    ArrayReference(const Vector<T, inlineCapacity>& vector)
        : m_data(vector.data())
        , m_size(vector.size())
    {
    }

    bool isEmpty() const { return !m_size; }

    size_t size() const { return m_size; }
    const T* data() const
    {
        if (isEmpty())
            return nullptr;
        return m_data;
    }

    Vector<T> vector() const
    {
        Vector<T> result;
        result.append(m_data, m_size);

        return result;
    }

private:
    const T* m_data { nullptr };
    size_t m_size { 0 };
};

template <typename T, size_t Extent>
class ArrayReference {
public:
    ArrayReference() = default;

    ArrayReference(const T* data, size_t size)
        : m_data(data)
    {
        ASSERT_UNUSED(size, size == Extent);
    }

    template <size_t inlineCapacity>
    ArrayReference(const Vector<T, inlineCapacity>& vector)
        : m_data(vector.data())
    {
        ASSERT(vector.size() == Extent);
    }

    constexpr bool isEmpty() const { return !Extent; }

    constexpr size_t size() const { return Extent; }

    const T* data() const
    {
        if (isEmpty())
            return nullptr;
        return m_data;
    }

    Vector<T> vector() const
    {
        Vector<T> result;
        if (!isEmpty())
            result.append(m_data, Extent);
        return result;
    }

private:
    const T* m_data { nullptr };
};

template<typename T, size_t inlineCapacity>
ArrayReference(const WTF::Vector<T, inlineCapacity>&) -> ArrayReference<T>;

} // namespace IPC