text: // Copyright (c) 2018-2021, CUT coin
  // Copyright (c) 2014-2018, The Monero Project
  // 
  // All rights reserved.
  // 
  // Redistribution and use in source and binary forms, with or without modification, are
  // permitted provided that the following conditions are met:
  // 
  // 1. Redistributions of source code must retain the above copyright notice, this list of
  //    conditions and the following disclaimer.
  // 
  // 2. Redistributions in binary form must reproduce the above copyright notice, this list
  //    of conditions and the following disclaimer in the documentation and/or other
  //    materials provided with the distribution.
  // 
  // 3. Neither the name of the copyright holder nor the names of its contributors may be
  //    used to endorse or promote products derived from this software without specific
  //    prior written permission.
  // 
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
  // EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  // MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
  // THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  // PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
  // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  // 
  // Parts of this file are originally copyright (c) 2012-2013 The Cryptonote developers
  
  #pragma once
  
  #include <cstddef>
  #include <cstring>
  #include <functional>
  #include <sodium/crypto_verify_32.h>
  
  #define CRYPTO_MAKE_COMPARABLE(type) \
  namespace crypto { \
    inline bool operator==(const type &_v1, const type &_v2) { \
      return !memcmp(&_v1, &_v2, sizeof(_v1)); \
    } \
    inline bool operator!=(const type &_v1, const type &_v2) { \
      return !operator==(_v1, _v2); \
    } \
  }
  
  #define CRYPTO_MAKE_COMPARABLE_CONSTANT_TIME(type) \
  namespace crypto { \
    inline bool operator==(const type &_v1, const type &_v2) { \
      static_assert(sizeof(_v1) == 32, "constant time comparison is only implenmted for 32 bytes"); \
      return crypto_verify_32((const unsigned char*)&_v1, (const unsigned char*)&_v2) == 0; \
    } \
    inline bool operator!=(const type &_v1, const type &_v2) { \
      return !operator==(_v1, _v2); \
    } \
  }
  
  #define CRYPTO_DEFINE_HASH_FUNCTIONS(type) \
  namespace crypto { \
    static_assert(sizeof(std::size_t) <= sizeof(type), "Size of " #type " must be at least that of size_t"); \
    inline std::size_t hash_value(const type &_v) { \
      return reinterpret_cast<const std::size_t &>(_v); \
    } \
  } \
  namespace std { \
    template<> \
    struct hash<crypto::type> { \
      std::size_t operator()(const crypto::type &_v) const { \
        return reinterpret_cast<const std::size_t &>(_v); \
      } \
    }; \
  }
  
  #define CRYPTO_MAKE_HASHABLE(type) \
  CRYPTO_MAKE_COMPARABLE(type) \
  CRYPTO_DEFINE_HASH_FUNCTIONS(type)
  
  #define CRYPTO_MAKE_HASHABLE_CONSTANT_TIME(type) \
  CRYPTO_MAKE_COMPARABLE_CONSTANT_TIME(type) \
  CRYPTO_DEFINE_HASH_FUNCTIONS(type)
  
  