allocated_ptr.hpp

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#ifndef MSTL_CORE_MEMORY_ALLOCATED_PTR_HPP__
#define MSTL_CORE_MEMORY_ALLOCATED_PTR_HPP__

 
#include "MSTL/core/memory/allocator_traits.hpp"
MSTL_BEGIN_NAMESPACE__


template <typename Alloc>
struct allocated_ptr {
    using pointer = typename allocator_traits<Alloc>::pointer;   
    using value_type = typename allocator_traits<Alloc>::value_type; 
 
private:
    Alloc* alloc_; 
    pointer ptr_;  
 
public:
    allocated_ptr(Alloc& alloc, pointer ptr) noexcept
    : alloc_(_MSTL addressof(alloc)), ptr_(ptr) {}

    template <typename Ptr, typename = enable_if_t<is_same_v<Ptr, value_type*>>>
    allocated_ptr(Alloc& alloc, Ptr ptr)
    : alloc_(_MSTL addressof(alloc)), ptr_(pointer_traits<pointer>::pointer_to(*ptr)) {}

    allocated_ptr(allocated_ptr&& guard) noexcept
    : alloc_(guard.alloc_), ptr_(guard.ptr_) {
        guard.ptr_ = nullptr;
    }

    ~allocated_ptr() {
        if (ptr_ != nullptr) {
          _MSTL allocator_traits<Alloc>::deallocate(*alloc_, ptr_, 1);
        }
    }

    allocated_ptr& operator =(nullptr_t null) noexcept {
        ptr_ = nullptr;
        return *this;
    }

    value_type* get() {
        return _MSTL to_address(ptr_);
    }
};

template <typename Alloc>
allocated_ptr<Alloc> allocate_guarded(Alloc& alloc) {
    return allocated_ptr<Alloc>{alloc, _MSTL allocator_traits<Alloc>::allocate(alloc, 1)};
}
 // AllocatedPtr
 
MSTL_END_NAMESPACE__
#endif // MSTL_CORE_MEMORY_ALLOCATED_PTR_HPP__