memwipe.h

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// Copyright (c) 2017-2022, The Monero Project
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// Parts of this file are originally copyright (c) 2012-2013 The Cryptonote developers
 
#pragma once
 
#ifdef __cplusplus
#include <array>
#include <cstddef>
 
extern "C" {
#endif
 
void *memwipe(void *src, size_t n);
 
#ifdef __cplusplus
}
#endif
 
#ifdef __cplusplus
namespace tools {

  template <class T>
  struct scrubbed : public T {
    using type = T;
 
    ~scrubbed() {
      scrub();
    }

    void scrub() {
      static_assert(std::is_pod<T>::value,
                    "T cannot be auto-scrubbed. T must be POD.");
      static_assert(std::is_trivially_destructible<T>::value,
                    "T cannot be auto-scrubbed. T must be trivially destructable.");
      memwipe(this, sizeof(T));
    }
  };
 
  template<typename T>
  T& unwrap(scrubbed<T>& src) { return src; }
 
  template<typename T>
  const T& unwrap(scrubbed<T> const& src) { return src; }
 
  template <class T, size_t N>
  using scrubbed_arr = scrubbed<std::array<T, N>>;
} // namespace tools
 
#endif // __cplusplus