src/metadata.cpp

   1 /*
   2 Minetest
   3 Copyright (C) 2010-2013 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 #include "metadata.h"
  21 #include "log.h"
  22
  23 /*
  24         Metadata
  25 */
  26
  27 void Metadata::clear()
  28 {
  29         m_stringvars.clear();
  30         m_modified = true;
  31 }
  32
  33 bool Metadata::empty() const
  34 {
  35         return m_stringvars.empty();
  36 }
  37
  38 size_t Metadata::size() const
  39 {
  40         return m_stringvars.size();
  41 }
  42
  43 bool Metadata::contains(const std::string &name) const
  44 {
  45         return m_stringvars.find(name) != m_stringvars.end();
  46 }
  47
  48 bool Metadata::operator==(const Metadata &other) const
  49 {
  50         if (size() != other.size())
  51                 return false;
  52
  53         for (const auto &sv : m_stringvars) {
  54                 if (!other.contains(sv.first) || other.getString(sv.first) != sv.second)
  55                         return false;
  56         }
  57
  58         return true;
  59 }
  60
  61 const std::string &Metadata::getString(const std::string &name, u16 recursion) const
  62 {
  63         StringMap::const_iterator it = m_stringvars.find(name);
  64         if (it == m_stringvars.end()) {
  65                 static const std::string empty_string = std::string("");
  66                 return empty_string;
  67         }
  68
  69         return resolveString(it->second, recursion);
  70 }
  71
  72 bool Metadata::getStringToRef(
  73                 const std::string &name, std::string &str, u16 recursion) const
  74 {
  75         StringMap::const_iterator it = m_stringvars.find(name);
  76         if (it == m_stringvars.end()) {
  77                 return false;
  78         }
  79
  80         str = resolveString(it->second, recursion);
  81         return true;
  82 }
  83
  84 /**
  85  * Sets var to name key in the metadata storage
  86  *
  87  * @param name
  88  * @param var
  89  * @return true if key-value pair is created or changed
  90  */
  91 bool Metadata::setString(const std::string &name, const std::string &var)
  92 {
  93         if (var.empty()) {
  94                 m_stringvars.erase(name);
  95                 return true;
  96         }
  97
  98         StringMap::iterator it = m_stringvars.find(name);
  99         if (it != m_stringvars.end() && it->second == var) {
 100                 return false;
 101         }
 102
 103         m_stringvars[name] = var;
 104         m_modified = true;
 105         return true;
 106 }
 107
 108 const std::string &Metadata::resolveString(const std::string &str, u16 recursion) const
 109 {
 110         if (recursion <= 1 && str.substr(0, 2) == "${" && str[str.length() - 1] == '}') {
 111                 return getString(str.substr(2, str.length() - 3), recursion + 1);
 112         }
 113
 114         return str;
 115 }