src/util/strfnd.h

   1 /*
   2 Minetest
   3 Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
   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 template <typename T>
  25 class BasicStrfnd {
  26         typedef std::basic_string<T> String;
  27         String str;
  28         size_t pos;
  29 public:
  30         BasicStrfnd(const String &s) : str(s), pos(0) {}
  31         void start(const String &s) { str = s; pos = 0; }
  32         size_t where() { return pos; }
  33         void to(size_t i) { pos = i; }
  34         bool at_end() { return pos >= str.size(); }
  35         String what() { return str; }
  36
  37         String next(const String &sep)
  38         {
  39                 if (pos >= str.size())
  40                         return String();
  41
  42                 size_t n;
  43                 if (sep.empty() || (n = str.find(sep, pos)) == String::npos) {
  44                         n = str.size();
  45                 }
  46                 String ret = str.substr(pos, n - pos);
  47                 pos = n + sep.size();
  48                 return ret;
  49         }
  50
  51         // Returns substr up to the next occurence of sep that isn't escaped with esc ('\\')
  52         String next_esc(const String &sep, T esc=static_cast<T>('\\'))
  53         {
  54                 if (pos >= str.size())
  55                         return String();
  56
  57                 size_t n, old_p = pos;
  58                 do {
  59                         if (sep.empty() || (n = str.find(sep, pos)) == String::npos) {
  60                                 pos = n = str.size();
  61                                 break;
  62                         }
  63                         pos = n + sep.length();
  64                 } while (n > 0 && str[n - 1] == esc);
  65
  66                 return str.substr(old_p, n - old_p);
  67         }
  68
  69         void skip_over(const String &chars)
  70         {
  71                 size_t p = str.find_first_not_of(chars, pos);
  72                 if (p != String::npos)
  73                         pos = p;
  74         }
  75 };
  76
  77 typedef BasicStrfnd<char> Strfnd;
  78 typedef BasicStrfnd<wchar_t> WStrfnd;