1  // Copyright (c) 2009-present The Bitcoin Core developers
 2  // Distributed under the MIT software license, see the accompanying
 3  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 4  
 5  #ifndef BITCOIN_CRYPTO_HEX_BASE_H
 6  #define BITCOIN_CRYPTO_HEX_BASE_H
 7  
 8  #include <span.h>
 9  
10  #include <cstddef>
11  #include <cstdint>
12  #include <span>
13  #include <string>
14  
15  /**
16   * Convert a span of bytes to a lower-case hexadecimal string.
17   */
18  std::string HexStr(std::span<const uint8_t> s);
19  inline std::string HexStr(std::span<const char> s) { return HexStr(MakeUCharSpan(s)); }
20  inline std::string HexStr(std::span<const std::byte> s) { return HexStr(MakeUCharSpan(s)); }
21  
22  signed char HexDigit(char c);
23  
24  #endif // BITCOIN_CRYPTO_HEX_BASE_H