Class custom_allocator

tests/custom_allocator_tests.cpp:39–95

template <typename T>
class custom_allocator {
 public:
  using value_type = T;
  using pointer = T*;
  using const_pointer = const T*;
  using reference = T&;
  using const_reference = const T&;
  using size_type = std::size_t;
  using difference_type = std::ptrdiff_t;
  using propagate_on_container_move_assignment = std::true_type;

  template <typename U>
  struct rebind {
    using other = custom_allocator<U>;
  };

  custom_allocator() = default;
  custom_allocator(const custom_allocator&) = default;

  template <typename U>
  custom_allocator(const custom_allocator<U>&) {}

  pointer address(reference x) const noexcept { return &x; }

  const_pointer address(const_reference x) const noexcept { return &x; }

  pointer allocate(size_type n, const void* /*hint*/ = 0) {
    nb_custom_allocs++;

    pointer ptr = static_cast<pointer>(std::malloc(n * sizeof(T)));
    if (ptr == nullptr) {
#ifdef TSL_OH_NO_EXCEPTIONS
      std::abort();
#else
      throw std::bad_alloc();
#endif
    }

    return ptr;
  }

  void deallocate(T* p, size_type /*n*/) { std::free(p); }

  size_type max_size() const noexcept {
    return std::numeric_limits<size_type>::max() / sizeof(value_type);
  }

  template <typename U, typename... Args>
  void construct(U* p, Args&&... args) {
    ::new (static_cast<void*>(p)) U(std::forward<Args>(args)...);
  }

  template <typename U>
  void destroy(U* p) {
    p->~U();
  }
};