text: // Copyright (c) 2009-2010 Satoshi Nakamoto
  // Copyright (c) 2009-2015 The Bitcoin Core developers
  // Copyright (c) 2019-2020 The Billiecoin Core developers
  // Distributed under the MIT software license, see the accompanying
  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  
  #ifndef BILLIECOIN_SUPPORT_ALLOCATORS_ZEROAFTERFREE_H
  #define BILLIECOIN_SUPPORT_ALLOCATORS_ZEROAFTERFREE_H
  
  #include "support/cleanse.h"
  
  #include <memory>
  #include <vector>
  
  template <typename T>
  struct zero_after_free_allocator : public std::allocator<T> {
      // MSVC8 default copy constructor is broken
      typedef std::allocator<T> base;
      typedef typename base::size_type size_type;
      typedef typename base::difference_type difference_type;
      typedef typename base::pointer pointer;
      typedef typename base::const_pointer const_pointer;
      typedef typename base::reference reference;
      typedef typename base::const_reference const_reference;
      typedef typename base::value_type value_type;
      zero_after_free_allocator() throw() {}
      zero_after_free_allocator(const zero_after_free_allocator& a) throw() : base(a) {}
      template <typename U>
      zero_after_free_allocator(const zero_after_free_allocator<U>& a) throw() : base(a)
      {
      }
      ~zero_after_free_allocator() throw() {}
      template <typename _Other>
      struct rebind {
          typedef zero_after_free_allocator<_Other> other;
      };
  
      void deallocate(T* p, std::size_t n)
      {
          if (p != NULL)
              memory_cleanse(p, sizeof(T) * n);
          std::allocator<T>::deallocate(p, n);
      }
  };
  
  // Byte-vector that clears its contents before deletion.
  typedef std::vector<char, zero_after_free_allocator<char> > CSerializeData;
  
  #endif // BILLIECOIN_SUPPORT_ALLOCATORS_ZEROAFTERFREE_H
  