text: // Copyright (c) 2014-2022 The Bitcoin Core developers
  // Distributed under the MIT software license, see the accompanying
  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  
  #ifndef BITCOIN_CRYPTO_SHA512_H
  #define BITCOIN_CRYPTO_SHA512_H
  
  #include <stdint.h>
  #include <stdlib.h>
  
  /** A hasher class for SHA-512. */
  class CSHA512
  {
  private:
      uint64_t s[8];
      unsigned char buf[128];
      uint64_t bytes;
  
  public:
      static const size_t OUTPUT_SIZE = 64;
  
      CSHA512();
      CSHA512& Write(const unsigned char* data, size_t len);
      void Finalize(unsigned char hash[OUTPUT_SIZE]);
      CSHA512& Reset();
  };
  
  #endif // BITCOIN_CRYPTO_SHA512_H
  