libs/ardour/ardour/configuration_variable.h

   1 /*
   2     Copyright (C) 2000-2007 Paul Davis
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18 */
  19
  20 #ifndef __ardour_configuration_variable_h__
  21 #define __ardour_configuration_variable_h__
  22
  23 #include <sstream>
  24 #include <ostream>
  25 #include <iostream>
  26
  27 #include <pbd/xml++.h>
  28
  29 namespace ARDOUR {
  30
  31 class ConfigVariableBase {
  32   public:
  33         enum Owner {
  34                 Default = 0x1,
  35                 System = 0x2,
  36                 Config = 0x4,
  37                 Session = 0x8,
  38                 Interface = 0x10
  39         };
  40
  41         ConfigVariableBase (std::string str) : _name (str), _owner (Default) {}
  42         virtual ~ConfigVariableBase() {}
  43
  44         std::string name() const { return _name; }
  45         Owner owner() const { return _owner; }
  46
  47         virtual void add_to_node (XMLNode& node) = 0;
  48         virtual bool set_from_node (const XMLNode& node, Owner owner) = 0;
  49
  50         void show_stored_value (const std::string&);
  51         static void set_show_stored_values (bool yn);
  52
  53   protected:
  54         std::string _name;
  55         Owner _owner;
  56         static bool show_stores;
  57
  58         void notify ();
  59         void miss ();
  60 };
  61
  62 template<class T>
  63 class ConfigVariable : public ConfigVariableBase
  64 {
  65   public:
  66         ConfigVariable (std::string str) : ConfigVariableBase (str) {}
  67         ConfigVariable (std::string str, T val) : ConfigVariableBase (str), value (val) {}
  68
  69         virtual bool set (T val, Owner owner = ARDOUR::ConfigVariableBase::Config) {
  70                 if (val == value) {
  71                         miss ();
  72                         return false;
  73                 }
  74                 value = val;
  75                 _owner = (ConfigVariableBase::Owner)(_owner |owner);
  76                 notify ();
  77                 return true;
  78         }
  79
  80         T get() const {
  81                 return value;
  82         }
  83
  84         void add_to_node (XMLNode& node) {
  85                 std::stringstream ss;
  86                 ss << value;
  87                 show_stored_value (ss.str());
  88                 XMLNode* child = new XMLNode ("Option");
  89                 child->add_property ("name", _name);
  90                 child->add_property ("value", ss.str());
  91                 node.add_child_nocopy (*child);
  92         }
  93
  94         bool set_from_node (const XMLNode& node, Owner owner) {
  95
  96                 if (node.name() == "Config") {
  97
  98                         /* ardour.rc */
  99
 100                         const XMLProperty* prop;
 101                         XMLNodeList nlist;
 102                         XMLNodeConstIterator niter;
 103                         XMLNode* child;
 104
 105                         nlist = node.children();
 106
 107                         for (niter = nlist.begin(); niter != nlist.end(); ++niter) {
 108
 109                                 child = *niter;
 110
 111                                 if (child->name() == "Option") {
 112                                         if ((prop = child->property ("name")) != 0) {
 113                                                 if (prop->value() == _name) {
 114                                                         if ((prop = child->property ("value")) != 0) {
 115                                                                 std::stringstream ss;
 116                                                                 ss << prop->value();
 117                                                                 ss >> value;
 118                                                                 _owner = (ConfigVariableBase::Owner)(_owner |owner);
 119                                                                 return true;
 120                                                         }
 121                                                 }
 122                                         }
 123                                 }
 124                         }
 125
 126                 } else if (node.name() == "Options") {
 127
 128                         /* session file */
 129
 130                         XMLNodeList olist;
 131                         XMLNodeConstIterator oiter;
 132                         XMLNode* option;
 133                         const XMLProperty* opt_prop;
 134
 135                         olist = node.children();
 136
 137                         for (oiter = olist.begin(); oiter != olist.end(); ++oiter) {
 138
 139                                 option = *oiter;
 140
 141                                 if (option->name() == _name) {
 142                                         if ((opt_prop = option->property ("val")) != 0) {
 143                                                 std::stringstream ss;
 144                                                 ss << opt_prop->value();
 145                                                 ss >> value;
 146                                                 _owner = (ConfigVariableBase::Owner)(_owner |owner);
 147                                                 return true;
 148                                         }
 149                                 }
 150                         }
 151                 }
 152
 153                 return false;
 154         }
 155
 156   protected:
 157         virtual T get_for_save() { return value; }
 158         T value;
 159 };
 160
 161 template<class T>
 162 class ConfigVariableWithMutation : public ConfigVariable<T>
 163 {
 164   public:
 165         ConfigVariableWithMutation (std::string name, T val, T (*m)(T))
 166                 : ConfigVariable<T> (name, val), mutator (m) {}
 167
 168         bool set (T val, ConfigVariableBase::Owner owner) {
 169                 if (unmutated_value != val) {
 170                         unmutated_value = val;
 171                         return ConfigVariable<T>::set (mutator (val), owner);
 172                 }
 173                 return false;
 174         }
 175
 176   protected:
 177         virtual T get_for_save() { return unmutated_value; }
 178         T unmutated_value;
 179         T (*mutator)(T);
 180 };
 181
 182 }
 183
 184 #endif /* __ardour_configuration_variable_h__ */