text: // Copyright (c) 2014-2016 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 FABCOIN_CRYPTO_SHA256_H
  #define FABCOIN_CRYPTO_SHA256_H
  
  #include <stdint.h>
  #include <stdlib.h>
  #include <string>
  
  /** A hasher class for SHA-256. */
  class CSHA256
  {
  private:
      uint32_t s[8];
      unsigned char buf[64];
      uint64_t bytes;
  
  public:
      static const size_t OUTPUT_SIZE = 32;
  
      CSHA256();
      CSHA256& Write(const unsigned char* data, size_t len);
      void Finalize(unsigned char hash[OUTPUT_SIZE]);
      CSHA256& Reset();
  };
  
  /** Autodetect the best available SHA256 implementation.
   *  Returns the name of the implementation.
   */
  std::string SHA256AutoDetect();
  
  #endif // FABCOIN_CRYPTO_SHA256_H
  