src/util/hex.h

   1 /*
   2 Minetest
   3 Copyright (C) 2013 Jonathan Neuschäfer <j.neuschaefer@gmx.net>
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU Lesser General Public License as published by
   7 the Free Software Foundation; either version 2.1 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU Lesser General Public License for more details.
  14
  15 You should have received a copy of the GNU Lesser General Public License along
  16 with this program; if not, write to the Free Software Foundation, Inc.,
  17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #pragma once
  21
  22 #include <string>
  23
  24 static const char hex_chars[] = "0123456789abcdef";
  25
  26 static inline std::string hex_encode(const char *data, unsigned int data_size)
  27 {
  28         std::string ret;
  29         ret.reserve(data_size * 2);
  30
  31         char buf2[3];
  32         buf2[2] = '\0';
  33
  34         for (unsigned int i = 0; i < data_size; i++) {
  35                 unsigned char c = (unsigned char)data[i];
  36                 buf2[0] = hex_chars[(c & 0xf0) >> 4];
  37                 buf2[1] = hex_chars[c & 0x0f];
  38                 ret.append(buf2);
  39         }
  40
  41         return ret;
  42 }
  43
  44 static inline std::string hex_encode(const std::string &data)
  45 {
  46         return hex_encode(data.c_str(), data.size());
  47 }
  48
  49 static inline bool hex_digit_decode(char hexdigit, unsigned char &value)
  50 {
  51         if (hexdigit >= '0' && hexdigit <= '9')
  52                 value = hexdigit - '0';
  53         else if (hexdigit >= 'A' && hexdigit <= 'F')
  54                 value = hexdigit - 'A' + 10;
  55         else if (hexdigit >= 'a' && hexdigit <= 'f')
  56                 value = hexdigit - 'a' + 10;
  57         else
  58                 return false;
  59         return true;
  60 }