X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/59ba8415761f72b7ce056bb275aeaebb6a507156..0a98e0dd953ca1a907d77f3c4eabdce39e62c1e5:/src/xbt/config.cpp

diff --git a/src/xbt/config.cpp b/src/xbt/config.cpp
index 16c47dc636..f70eec1947 100644
--- a/src/xbt/config.cpp
+++ b/src/xbt/config.cpp
@@ -1,4 +1,4 @@
-/* Copyright (c) 2004-2018. The SimGrid Team. All rights reserved.     */
+/* Copyright (c) 2004-2019. The SimGrid Team. All rights reserved.     */
 
 /* This program is free software; you can redistribute it and/or modify it
  * under the terms of the license (GNU LGPL) which comes with this package. */
@@ -12,6 +12,7 @@
 
 #include <functional>
 #include <map>
+#include <memory>
 #include <stdexcept>
 #include <string>
 #include <string>
@@ -19,6 +20,7 @@
 #include <typeinfo>
 #include <vector>
 
+#include "simgrid/Exception.hpp"
 #include "simgrid/sg_config.hpp"
 #include "xbt/dynar.h"
 #include "xbt/log.h"
@@ -26,7 +28,6 @@
 #include "xbt/sysdep.h"
 #include <xbt/config.h>
 #include <xbt/config.hpp>
-#include <xbt/ex.hpp>
 
 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(xbt_cfg, xbt, "configuration support");
 
@@ -35,8 +36,6 @@ XBT_EXPORT_NO_IMPORT xbt_cfg_t simgrid_config = nullptr;
 namespace simgrid {
 namespace config {
 
-missing_key_error::~missing_key_error() = default;
-
 namespace {
 
 const char* true_values[] = {
@@ -46,7 +45,7 @@ const char* false_values[] = {
   "no", "off", "false", "0"
 };
 
-static bool parseBool(const char* value)
+static bool parse_bool(const char* value)
 {
   for (const char* const& true_value : true_values)
     if (std::strcmp(true_value, value) == 0)
@@ -57,7 +56,7 @@ static bool parseBool(const char* value)
   throw std::range_error("not a boolean");
 }
 
-static double parseDouble(const char* value)
+static double parse_double(const char* value)
 {
   char* end;
   errno = 0;
@@ -72,7 +71,7 @@ static double parseDouble(const char* value)
     return res;
 }
 
-static long int parseLong(const char* value)
+static long int parse_long(const char* value)
 {
   char* end;
   errno = 0;
@@ -100,7 +99,7 @@ public:
   static constexpr const char* type_name = "int";
   static inline double parse(const char* value)
   {
-    return parseLong(value);
+    return parse_long(value);
   }
 };
 template <> class ConfigType<double> {
@@ -108,7 +107,7 @@ public:
   static constexpr const char* type_name = "double";
   static inline double parse(const char* value)
   {
-    return parseDouble(value);
+    return parse_double(value);
   }
 };
 template <> class ConfigType<std::string> {
@@ -124,7 +123,7 @@ public:
   static constexpr const char* type_name = "boolean";
   static inline bool parse(const char* value)
   {
-    return parseBool(value);
+    return parse_bool(value);
   }
 };
 
@@ -145,36 +144,35 @@ public:
   /* Callback */
   xbt_cfg_cb_t old_callback = nullptr;
 
-  ConfigurationElement(const char* key, const char* desc) : key(key ? key : ""), desc(desc ? desc : "") {}
-  ConfigurationElement(const char* key, const char* desc, xbt_cfg_cb_t cb)
-    : key(key ? key : ""), desc(desc ? desc : ""), old_callback(cb) {}
+  ConfigurationElement(const std::string& key, const std::string& desc) : key(key), desc(desc) {}
+  ConfigurationElement(const std::string& key, const std::string& desc, xbt_cfg_cb_t cb)
+      : key(key), desc(desc), old_callback(cb)
+  {
+  }
 
-  virtual ~ConfigurationElement()=default;
+  virtual ~ConfigurationElement() = default;
 
-  virtual std::string getStringValue() = 0;
-  virtual void setStringValue(const char* value) = 0;
-  virtual const char* getTypeName() = 0;
+  virtual std::string get_string_value()           = 0;
+  virtual void set_string_value(const char* value) = 0;
+  virtual const char* get_type_name()              = 0;
 
-  template<class T>
-  T const& getValue() const
+  template <class T> T const& get_value() const
   {
-    return dynamic_cast<const TypedConfigurationElement<T>&>(*this).getValue();
+    return static_cast<const TypedConfigurationElement<T>&>(*this).get_value();
   }
-  template<class T>
-  void setValue(T value)
+  template <class T> void set_value(T value)
   {
-    dynamic_cast<TypedConfigurationElement<T>&>(*this).setValue(std::move(value));
+    static_cast<TypedConfigurationElement<T>&>(*this).set_value(std::move(value));
   }
-  template<class T>
-  void setDefaultValue(T value)
+  template <class T> void set_default_value(T value)
   {
-    dynamic_cast<TypedConfigurationElement<T>&>(*this).setDefaultValue(std::move(value));
+    static_cast<TypedConfigurationElement<T>&>(*this).set_default_value(std::move(value));
   }
-  void unsetDefault() { isdefault = false; }
-  bool isDefault() const { return isdefault; }
+  void unset_default() { isdefault = false; }
+  bool is_default() const { return isdefault; }
 
-  std::string const& getDescription() const { return desc; }
-  std::string const& getKey() const { return key; }
+  std::string const& get_description() const { return desc; }
+  std::string const& get_key() const { return key; }
 };
 
 // **** TypedConfigurationElement<T> ****
@@ -187,65 +185,63 @@ private:
   std::function<void(T&)> callback;
 
 public:
-  TypedConfigurationElement(const char* key, const char* desc, T value = T())
-    : ConfigurationElement(key, desc), content(std::move(value))
+  TypedConfigurationElement(const std::string& key, const std::string& desc, T value = T())
+      : ConfigurationElement(key, desc), content(std::move(value))
   {}
-  TypedConfigurationElement(const char* key, const char* desc, T value, xbt_cfg_cb_t cb)
+  TypedConfigurationElement(const std::string& key, const std::string& desc, T value, xbt_cfg_cb_t cb)
       : ConfigurationElement(key, desc, cb), content(std::move(value))
   {}
-  TypedConfigurationElement(const char* key, const char* desc, T value, std::function<void(T&)> callback)
+  TypedConfigurationElement(const std::string& key, const std::string& desc, T value, std::function<void(T&)> callback)
       : ConfigurationElement(key, desc), content(std::move(value)), callback(std::move(callback))
   {}
   ~TypedConfigurationElement() = default;
 
-  std::string getStringValue() override;
-  const char* getTypeName() override;
-  void setStringValue(const char* value) override;
+  std::string get_string_value() override;
+  const char* get_type_name() override;
+  void set_string_value(const char* value) override;
 
   void update()
   {
     if (old_callback)
-      this->old_callback(getKey().c_str());
+      this->old_callback(get_key().c_str());
     if (this->callback)
       this->callback(this->content);
   }
 
-  T const& getValue() const { return content; }
+  T const& get_value() const { return content; }
 
-  void setValue(T value)
+  void set_value(T value)
   {
     this->content = std::move(value);
     this->update();
+    this->unset_default();
   }
 
-  void setDefaultValue(T value)
+  void set_default_value(T value)
   {
-    if (this->isDefault()) {
+    if (this->is_default()) {
       this->content = std::move(value);
       this->update();
     } else {
       XBT_DEBUG("Do not override configuration variable '%s' with value '%s' because it was already set.",
-                getKey().c_str(), to_string(value).c_str());
+                get_key().c_str(), to_string(value).c_str());
     }
   }
 };
 
-template<class T>
-std::string TypedConfigurationElement<T>::getStringValue() // override
+template <class T> std::string TypedConfigurationElement<T>::get_string_value() // override
 {
   return to_string(content);
 }
 
-template<class T>
-void TypedConfigurationElement<T>::setStringValue(const char* value) // override
+template <class T> void TypedConfigurationElement<T>::set_string_value(const char* value) // override
 {
   this->content = ConfigType<T>::parse(value);
-  this->unsetDefault();
+  this->unset_default();
   this->update();
 }
 
-template<class T>
-const char* TypedConfigurationElement<T>::getTypeName() // override
+template <class T> const char* TypedConfigurationElement<T>::get_type_name() // override
 {
   return ConfigType<T>::type_name;
 }
@@ -257,81 +253,75 @@ const char* TypedConfigurationElement<T>::getTypeName() // override
 class Config {
 private:
   // name -> ConfigElement:
-  std::map<std::string, simgrid::config::ConfigurationElement*> options;
+  std::map<std::string, std::unique_ptr<ConfigurationElement>> options;
   // alias -> ConfigElement from options:
-  std::map<std::string, simgrid::config::ConfigurationElement*> aliases;
+  std::map<std::string, ConfigurationElement*> aliases;
   bool warn_for_aliases = true;
 
 public:
-  Config() = default;
-  ~Config();
+  Config();
 
   // No copy:
   Config(Config const&) = delete;
   Config& operator=(Config const&) = delete;
 
-  ConfigurationElement& operator[](const char* name);
-  template<class T>
-  TypedConfigurationElement<T>& getTyped(const char* name);
-  void alias(const char* realname, const char* aliasname);
+  ConfigurationElement& operator[](const std::string& name);
+  void alias(const std::string& realname, const std::string& aliasname);
 
-  template<class T, class... A>
-  simgrid::config::TypedConfigurationElement<T>*
-    registerOption(const char* name, A&&... a)
+  template <class T, class... A> TypedConfigurationElement<T>* register_option(const std::string& name, A&&... a)
   {
-    xbt_assert(options.find(name) == options.end(), "Refusing to register the config element '%s' twice.", name);
+    xbt_assert(options.find(name) == options.end(), "Refusing to register the config element '%s' twice.",
+               name.c_str());
     TypedConfigurationElement<T>* variable = new TypedConfigurationElement<T>(name, std::forward<A>(a)...);
-    XBT_DEBUG("Register cfg elm %s (%s) of type %s @%p in set %p)", name, variable->getDescription().c_str(),
-              variable->getTypeName(), variable, this);
-    options.insert({name, variable});
+    XBT_DEBUG("Register cfg elm %s (%s) of type %s @%p in set %p)", name.c_str(), variable->get_description().c_str(),
+              variable->get_type_name(), variable, this);
+    options[name].reset(variable);
     variable->update();
     return variable;
   }
 
   // Debug:
   void dump(const char *name, const char *indent);
-  void showAliases();
+  void show_aliases();
   void help();
 
 protected:
-  ConfigurationElement* getDictElement(const char* name);
+  ConfigurationElement* get_dict_element(const std::string& name);
 };
 
-Config::~Config()
+Config::Config()
 {
-  XBT_DEBUG("Frees cfg set %p", this);
-  for (auto const& elm : options)
-    delete elm.second;
+  atexit(&sg_config_finalize);
 }
 
-inline ConfigurationElement* Config::getDictElement(const char* name)
+inline ConfigurationElement* Config::get_dict_element(const std::string& name)
 {
   auto opt = options.find(name);
   if (opt != options.end()) {
-    return opt->second;
+    return opt->second.get();
   } else {
     auto als = aliases.find(name);
     if (als != aliases.end()) {
       ConfigurationElement* res = als->second;
       if (warn_for_aliases)
-        XBT_INFO("Option %s has been renamed to %s. Consider switching.", name, res->getKey().c_str());
+        XBT_INFO("Option %s has been renamed to %s. Consider switching.", name.c_str(), res->get_key().c_str());
       return res;
     } else {
-      throw simgrid::config::missing_key_error(std::string("Bad config key: ") + name);
+      throw std::out_of_range("Bad config key: " + name);
     }
   }
 }
 
-inline ConfigurationElement& Config::operator[](const char* name)
+inline ConfigurationElement& Config::operator[](const std::string& name)
 {
-  return *(getDictElement(name));
+  return *(get_dict_element(name));
 }
 
-void Config::alias(const char* realname, const char* aliasname)
+void Config::alias(const std::string& realname, const std::string& aliasname)
 {
-  xbt_assert(aliases.find(aliasname) == aliases.end(), "Alias '%s' already.", aliasname);
-  ConfigurationElement* element = this->getDictElement(realname);
-  xbt_assert(element, "Cannot define an alias to the non-existing option '%s'.", realname);
+  xbt_assert(aliases.find(aliasname) == aliases.end(), "Alias '%s' already.", aliasname.c_str());
+  ConfigurationElement* element = this->get_dict_element(realname);
+  xbt_assert(element, "Cannot define an alias to the non-existing option '%s'.", realname.c_str());
   this->aliases.insert({aliasname, element});
 }
 
@@ -342,164 +332,84 @@ void Config::alias(const char* realname, const char* aliasname)
  */
 void Config::dump(const char *name, const char *indent)
 {
+  XBT_LOG_DEFAULT_CATEGORY(xbt_help);
   if (name)
-    printf("%s>> Dumping of the config set '%s':\n", indent, name);
+    XBT_VERB("%s>> Dumping of the config set '%s':", indent, name);
 
   for (auto const& elm : options)
-    printf("%s  %s: ()%s) %s", indent, elm.first.c_str(), elm.second->getTypeName(),
-           elm.second->getStringValue().c_str());
+    XBT_VERB("%s  %s: ()%s) %s", indent, elm.first.c_str(), elm.second->get_type_name(),
+             elm.second->get_string_value().c_str());
 
   if (name)
-    printf("%s<< End of the config set '%s'\n", indent, name);
-  fflush(stdout);
+    XBT_VERB("%s<< End of the config set '%s'", indent, name);
 }
 
-/** @brief Displays the declared aliases and their description */
-void Config::showAliases()
+/** @brief Displays the declared aliases and their replacement */
+void Config::show_aliases()
 {
-  bool old_warn_for_aliases = false;
-  std::swap(warn_for_aliases, old_warn_for_aliases);
   for (auto const& elm : aliases)
-    printf("   %s: %s\n", elm.first.c_str(), (*this)[elm.first.c_str()].getDescription().c_str());
-  std::swap(warn_for_aliases, old_warn_for_aliases);
+    XBT_HELP("   %-40s %s", elm.first.c_str(), elm.second->get_key().c_str());
 }
 
 /** @brief Displays the declared options and their description */
 void Config::help()
 {
   for (auto const& elm : options) {
-    simgrid::config::ConfigurationElement* variable = this->options.at(elm.first);
-    printf("   %s: %s\n", elm.first.c_str(), variable->getDescription().c_str());
-    printf("       Type: %s; ", variable->getTypeName());
-    printf("Current value: %s\n", variable->getStringValue().c_str());
+    simgrid::config::ConfigurationElement* variable = elm.second.get();
+    XBT_HELP("   %s: %s", elm.first.c_str(), variable->get_description().c_str());
+    XBT_HELP("       Type: %s; Current value: %s", variable->get_type_name(), variable->get_string_value().c_str());
   }
 }
 
-// ***** getConfig *****
+// ***** set_default *****
 
-template <class T> XBT_PUBLIC T const& getConfig(const char* name)
+template <class T> XBT_PUBLIC void set_default(const char* name, T value)
 {
-  return (*simgrid_config)[name].getValue<T>();
+  (*simgrid_config)[name].set_default_value<T>(std::move(value));
 }
 
-template XBT_PUBLIC int const& getConfig<int>(const char* name);
-template XBT_PUBLIC double const& getConfig<double>(const char* name);
-template XBT_PUBLIC bool const& getConfig<bool>(const char* name);
-template XBT_PUBLIC std::string const& getConfig<std::string>(const char* name);
+template XBT_PUBLIC void set_default<int>(const char* name, int value);
+template XBT_PUBLIC void set_default<double>(const char* name, double value);
+template XBT_PUBLIC void set_default<bool>(const char* name, bool value);
+template XBT_PUBLIC void set_default<std::string>(const char* name, std::string value);
 
-// ***** alias *****
-
-void alias(const char* realname, const char* aliasname)
-{
-  simgrid_config->alias(realname, aliasname);
-}
-
-// ***** declareFlag *****
-
-template <class T>
-XBT_PUBLIC void declareFlag(const char* name, const char* description, T value, std::function<void(const T&)> callback)
+bool is_default(const char* name)
 {
-  if (simgrid_config == nullptr)
-    simgrid_config = xbt_cfg_new();
-  simgrid_config->registerOption<T>(
-    name, description, std::move(value), std::move(callback));
+  return (*simgrid_config)[name].is_default();
 }
 
-template XBT_PUBLIC void declareFlag(const char* name, const char* description, int value,
-                                     std::function<void(int const&)> callback);
-template XBT_PUBLIC void declareFlag(const char* name, const char* description, double value,
-                                     std::function<void(double const&)> callback);
-template XBT_PUBLIC void declareFlag(const char* name, const char* description, bool value,
-                                     std::function<void(bool const&)> callback);
-template XBT_PUBLIC void declareFlag(const char* name, const char* description, std::string value,
-                                     std::function<void(std::string const&)> callback);
-}
-}
-
-// ***** C bindings *****
+// ***** set_value *****
 
-xbt_cfg_t xbt_cfg_new()
+template <class T> XBT_PUBLIC void set_value(const char* name, T value)
 {
-  atexit(&sg_config_finalize);
-  return new simgrid::config::Config();
+  (*simgrid_config)[name].set_value<T>(std::move(value));
 }
-void xbt_cfg_free(xbt_cfg_t * cfg) { delete *cfg; }
 
-void xbt_cfg_dump(const char *name, const char *indent, xbt_cfg_t cfg)
-{
-  cfg->dump(name, indent);
-}
-
-/*----[ Registering stuff ]-----------------------------------------------*/
+template XBT_PUBLIC void set_value<int>(const char* name, int value);
+template XBT_PUBLIC void set_value<double>(const char* name, double value);
+template XBT_PUBLIC void set_value<bool>(const char* name, bool value);
+template XBT_PUBLIC void set_value<std::string>(const char* name, std::string value);
 
-void xbt_cfg_register_double(const char *name, double default_value,
-  xbt_cfg_cb_t cb_set, const char *desc)
+void set_as_string(const char* name, const std::string& value)
 {
-  if (simgrid_config == nullptr)
-    simgrid_config = xbt_cfg_new();
-  simgrid_config->registerOption<double>(name, desc, default_value, cb_set);
+  (*simgrid_config)[name].set_string_value(value.c_str());
 }
 
-void xbt_cfg_register_int(const char *name, int default_value,xbt_cfg_cb_t cb_set, const char *desc)
+void set_parse(const std::string& opt)
 {
-  if (simgrid_config == nullptr)
-    simgrid_config = xbt_cfg_new();
-  simgrid_config->registerOption<int>(name, desc, default_value, cb_set);
-}
-
-void xbt_cfg_register_string(const char *name, const char *default_value, xbt_cfg_cb_t cb_set, const char *desc)
-{
-  if (simgrid_config == nullptr)
-    simgrid_config = xbt_cfg_new();
-  simgrid_config->registerOption<std::string>(name, desc, default_value ? default_value : "", cb_set);
-}
-
-void xbt_cfg_register_boolean(const char *name, const char*default_value,xbt_cfg_cb_t cb_set, const char *desc)
-{
-  if (simgrid_config == nullptr)
-    simgrid_config = xbt_cfg_new();
-  simgrid_config->registerOption<bool>(name, desc, simgrid::config::parseBool(default_value), cb_set);
-}
-
-void xbt_cfg_register_alias(const char *realname, const char *aliasname)
-{
-  if (simgrid_config == nullptr)
-    simgrid_config = xbt_cfg_new();
-  simgrid_config->alias(realname, aliasname);
-}
-
-void xbt_cfg_aliases() { simgrid_config->showAliases(); }
-void xbt_cfg_help()    { simgrid_config->help(); }
-
-/*----[ Setting ]---------------------------------------------------------*/
-
-/** @brief Add values parsed from a string into a config set
- *
- * @param options a string containing the content to add to the config set. This is a '\\t',' ' or '\\n' or ','
- * separated list of variables. Each individual variable is like "[name]:[value]" where [name] is the name of an
- * already registered variable, and [value] conforms to the data type under which this variable was registered.
- *
- * @todo This is a crude manual parser, it should be a proper lexer.
- */
-void xbt_cfg_set_parse(const char *options)
-{
-  if (not options || not strlen(options)) { /* nothing to do */
-    return;
-  }
-
-  XBT_DEBUG("List to parse and set:'%s'", options);
-  std::string optionlist(options);
-  while (not optionlist.empty()) {
-    XBT_DEBUG("Still to parse and set: '%s'", optionlist.c_str());
+  std::string options(opt);
+  XBT_DEBUG("List to parse and set:'%s'", options.c_str());
+  while (not options.empty()) {
+    XBT_DEBUG("Still to parse and set: '%s'", options.c_str());
 
     // skip separators
-    size_t pos = optionlist.find_first_not_of(" \t\n,");
-    optionlist.erase(0, pos);
+    size_t pos = options.find_first_not_of(" \t\n,");
+    options.erase(0, pos);
     // find option
-    pos              = optionlist.find_first_of(" \t\n,");
-    std::string name = optionlist.substr(0, pos);
-    optionlist.erase(0, pos);
-    XBT_DEBUG("parse now:'%s'; parse later:'%s'", name.c_str(), optionlist.c_str());
+    pos              = options.find_first_of(" \t\n,");
+    std::string name = options.substr(0, pos);
+    options.erase(0, pos);
+    XBT_DEBUG("parse now:'%s'; parse later:'%s'", name.c_str(), options.c_str());
 
     if (name.empty())
       continue;
@@ -515,101 +425,69 @@ void xbt_cfg_set_parse(const char *options)
     if (name.compare(0, path.length(), path) != 0)
       XBT_INFO("Configuration change: Set '%s' to '%s'", name.c_str(), val.c_str());
 
-    try {
-      (*simgrid_config)[name.c_str()].setStringValue(val.c_str());
-    }
-    catch (simgrid::config::missing_key_error& e) {
-      goto on_missing_key;
-    }
-    catch (...) {
-      goto on_exception;
-    }
+    set_as_string(name.c_str(), val);
   }
-  return;
+}
 
-  /* Do not THROWF from a C++ exception catching context, or some cleanups will be missing */
-on_missing_key:
-  THROWF(not_found_error, 0, "Could not set variables %s", options);
-on_exception:
-  THROWF(unknown_error, 0, "Could not set variables %s", options);
+// ***** get_value *****
+
+template <class T> XBT_PUBLIC T const& get_value(const std::string& name)
+{
+  return (*simgrid_config)[name].get_value<T>();
 }
 
-// Horrible mess to translate C++ exceptions to C exceptions:
-// Exit from the catch block (and do the correct exception cleaning) before attempting to THROWF.
-#define TRANSLATE_EXCEPTIONS(...) \
-  catch(simgrid::config::missing_key_error& e) { THROWF(not_found_error, 0, __VA_ARGS__); abort(); } \
-  catch(...) { THROWF(not_found_error, 0, __VA_ARGS__); abort(); }
+template XBT_PUBLIC int const& get_value<int>(const std::string& name);
+template XBT_PUBLIC double const& get_value<double>(const std::string& name);
+template XBT_PUBLIC bool const& get_value<bool>(const std::string& name);
+template XBT_PUBLIC std::string const& get_value<std::string>(const std::string& name);
 
-/** @brief Set the value of a variable, using the string representation of that value
- *
- * @param key name of the variable to modify
- * @param value string representation of the value to set
- */
+// ***** alias *****
 
-void xbt_cfg_set_as_string(const char *key, const char *value)
+void alias(const char* realname, std::initializer_list<const char*> aliases)
 {
-  try {
-    (*simgrid_config)[key].setStringValue(value);
-    return;
-  }
-  TRANSLATE_EXCEPTIONS("Could not set variable %s as string %s", key, value);
+  for (auto const& aliasname : aliases)
+    simgrid_config->alias(realname, aliasname);
 }
 
-/** @brief Set an integer value to \a name within \a cfg if it wasn't changed yet
- *
- * This is useful to change the default value of a variable while allowing
- * users to override it with command line arguments
- */
-void xbt_cfg_setdefault_int(const char *key, int value)
+// ***** declare_flag *****
+
+template <class T>
+XBT_PUBLIC void declare_flag(const std::string& name, const std::string& description, T value,
+                             std::function<void(const T&)> callback)
 {
-  try {
-    (*simgrid_config)[key].setDefaultValue<int>(value);
-    return;
-  }
-  TRANSLATE_EXCEPTIONS("Could not set variable %s to default integer %i", key, value);
+  if (simgrid_config == nullptr)
+    simgrid_config = new simgrid::config::Config();
+  simgrid_config->register_option<T>(name, description, std::move(value), std::move(callback));
 }
 
-/** @brief Set an integer value to \a name within \a cfg if it wasn't changed yet
- *
- * This is useful to change the default value of a variable while allowing
- * users to override it with command line arguments
- */
-void xbt_cfg_setdefault_double(const char *key, double value)
+template XBT_PUBLIC void declare_flag(const std::string& name, const std::string& description, int value,
+                                      std::function<void(int const&)> callback);
+template XBT_PUBLIC void declare_flag(const std::string& name, const std::string& description, double value,
+                                      std::function<void(double const&)> callback);
+template XBT_PUBLIC void declare_flag(const std::string& name, const std::string& description, bool value,
+                                      std::function<void(bool const&)> callback);
+template XBT_PUBLIC void declare_flag(const std::string& name, const std::string& description, std::string value,
+                                      std::function<void(std::string const&)> callback);
+
+void finalize()
 {
-  try {
-    (*simgrid_config)[key].setDefaultValue<double>(value);
-    return;
-  }
-  TRANSLATE_EXCEPTIONS("Could not set variable %s to default double %f", key, value);
+  delete simgrid_config;
+  simgrid_config = nullptr;
 }
 
-/** @brief Set a string value to \a name within \a cfg if it wasn't changed yet
- *
- * This is useful to change the default value of a variable while allowing
- * users to override it with command line arguments
- */
-void xbt_cfg_setdefault_string(const char *key, const char *value)
+void show_aliases()
 {
-  try {
-    (*simgrid_config)[key].setDefaultValue<std::string>(value ? value : "");
-    return;
-  }
-  TRANSLATE_EXCEPTIONS("Could not set variable %s to default string %s", key, value);
+  simgrid_config->show_aliases();
 }
 
-/** @brief Set an boolean value to \a name within \a cfg if it wasn't changed yet
- *
- * This is useful to change the default value of a variable while allowing
- * users to override it with command line arguments
- */
-void xbt_cfg_setdefault_boolean(const char *key, const char *value)
+void help()
 {
-  try {
-    (*simgrid_config)[key].setDefaultValue<bool>(simgrid::config::parseBool(value));
-    return;
-  }
-  TRANSLATE_EXCEPTIONS("Could not set variable %s to default boolean %s", key, value);
+  simgrid_config->help();
 }
+}
+}
+
+/*----[ Setting ]---------------------------------------------------------*/
 
 /** @brief Set an integer value to \a name within \a cfg
  *
@@ -618,11 +496,7 @@ void xbt_cfg_setdefault_boolean(const char *key, const char *value)
  */
 void xbt_cfg_set_int(const char *key, int value)
 {
-  try {
-    (*simgrid_config)[key].setValue<int>(value);
-    return;
-  }
-  TRANSLATE_EXCEPTIONS("Could not set variable %s to integer %i", key, value);
+  (*simgrid_config)[key].set_value<int>(value);
 }
 
 /** @brief Set or add a double value to \a name within \a cfg
@@ -632,11 +506,7 @@ void xbt_cfg_set_int(const char *key, int value)
  */
 void xbt_cfg_set_double(const char *key, double value)
 {
-  try {
-    (*simgrid_config)[key].setValue<double>(value);
-    return;
-  }
-  TRANSLATE_EXCEPTIONS("Could not set variable %s to double %f", key, value);
+  (*simgrid_config)[key].set_value<double>(value);
 }
 
 /** @brief Set or add a string value to \a name within \a cfg
@@ -647,11 +517,7 @@ void xbt_cfg_set_double(const char *key, double value)
  */
 void xbt_cfg_set_string(const char* key, const char* value)
 {
-  try {
-    (*simgrid_config)[key].setValue<std::string>(value);
-    return;
-  }
-  TRANSLATE_EXCEPTIONS("Could not set variable %s to string %s", key, value);
+  (*simgrid_config)[key].set_value<std::string>(value);
 }
 
 /** @brief Set or add a boolean value to \a name within \a cfg
@@ -661,21 +527,7 @@ void xbt_cfg_set_string(const char* key, const char* value)
  */
 void xbt_cfg_set_boolean(const char *key, const char *value)
 {
-  try {
-    (*simgrid_config)[key].setValue<bool>(simgrid::config::parseBool(value));
-    return;
-  }
-  TRANSLATE_EXCEPTIONS("Could not set variable %s to boolean %s", key, value);
-}
-
-
-/* Say if the value is the default value */
-int xbt_cfg_is_default_value(const char *key)
-{
-  try {
-    return (*simgrid_config)[key].isDefault() ? 1 : 0;
-  }
-  TRANSLATE_EXCEPTIONS("Could not get variable %s", key);
+  (*simgrid_config)[key].set_value<bool>(simgrid::config::parse_bool(value));
 }
 
 /*----[ Getting ]---------------------------------------------------------*/
@@ -687,10 +539,7 @@ int xbt_cfg_is_default_value(const char *key)
  */
 int xbt_cfg_get_int(const char *key)
 {
-  try {
-    return (*simgrid_config)[key].getValue<int>();
-  }
-  TRANSLATE_EXCEPTIONS("Could not get variable %s", key);
+  return (*simgrid_config)[key].get_value<int>();
 }
 
 /** @brief Retrieve a double value of a variable (get a warning if not uniq)
@@ -701,28 +550,7 @@ int xbt_cfg_get_int(const char *key)
  */
 double xbt_cfg_get_double(const char *key)
 {
-  try {
-    return (*simgrid_config)[key].getValue<double>();
-  }
-  TRANSLATE_EXCEPTIONS("Could not get variable %s", key);
-}
-
-/** @brief Retrieve a string value of a variable (get a warning if not uniq)
- *
- * @param key the name of the variable
- *
- * Returns the first value from the config set under the given name.
- * If there is more than one value, it will issue a warning.
- * Returns nullptr if there is no value.
- *
- * \warning the returned value is the actual content of the config set
- */
-std::string xbt_cfg_get_string(const char* key)
-{
-  try {
-    return (*simgrid_config)[key].getValue<std::string>();
-  }
-  TRANSLATE_EXCEPTIONS("Could not get variable %s", key);
+  return (*simgrid_config)[key].get_value<double>();
 }
 
 /** @brief Retrieve a boolean value of a variable (get a warning if not uniq)
@@ -734,95 +562,5 @@ std::string xbt_cfg_get_string(const char* key)
  */
 int xbt_cfg_get_boolean(const char *key)
 {
-  try {
-    return (*simgrid_config)[key].getValue<bool>() ? 1 : 0;
-  }
-  TRANSLATE_EXCEPTIONS("Could not get variable %s", key);
-}
-
-#ifdef SIMGRID_TEST
-
-#include <string>
-
-#include "xbt.h"
-#include "xbt/ex.h"
-#include <xbt/ex.hpp>
-
-#include <xbt/config.hpp>
-
-XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(xbt_cfg);
-
-XBT_TEST_SUITE("config", "Configuration support");
-
-XBT_PUBLIC_DATA xbt_cfg_t simgrid_config;
-
-static void make_set()
-{
-  simgrid_config = nullptr;
-  xbt_log_threshold_set(&_XBT_LOGV(xbt_cfg), xbt_log_priority_critical);
-  xbt_cfg_register_int("speed", 0, nullptr, "");
-  xbt_cfg_register_string("peername", "", nullptr, "");
-  xbt_cfg_register_string("user", "", nullptr, "");
-}                               /* end_of_make_set */
-
-XBT_TEST_UNIT("memuse", test_config_memuse, "Alloc and free a config set")
-{
-  auto temp = simgrid_config;
-  make_set();
-  xbt_test_add("Alloc and free a config set");
-  xbt_cfg_set_parse("peername:veloce user:bidule");
-  xbt_cfg_free(&simgrid_config);
-  simgrid_config = temp;
+  return (*simgrid_config)[key].get_value<bool>() ? 1 : 0;
 }
-
-XBT_TEST_UNIT("use", test_config_use, "Data retrieving tests")
-{
-  auto temp = simgrid_config;
-  make_set();
-  xbt_test_add("Get a single value");
-  {
-    /* get_single_value */
-    xbt_cfg_set_parse("peername:toto:42 speed:42");
-    int ival = xbt_cfg_get_int("speed");
-    if (ival != 42)
-      xbt_test_fail("Speed value = %d, I expected 42", ival);
-  }
-
-  xbt_test_add("Access to a non-existant entry");
-  {
-    try {
-      xbt_cfg_set_parse("color:blue");
-    } catch(xbt_ex& e) {
-      if (e.category != not_found_error)
-        xbt_test_exception(e);
-    }
-  }
-  xbt_cfg_free(&simgrid_config);
-  simgrid_config = temp;
-}
-
-XBT_TEST_UNIT("c++flags", test_config_cxx_flags, "C++ flags")
-{
-  auto temp = simgrid_config;
-  make_set();
-  xbt_test_add("C++ declaration of flags");
-
-  simgrid::config::Flag<int> int_flag("int", "", 0);
-  simgrid::config::Flag<std::string> string_flag("string", "", "foo");
-  simgrid::config::Flag<double> double_flag("double", "", 0.32);
-  simgrid::config::Flag<bool> bool_flag1("bool1", "", false);
-  simgrid::config::Flag<bool> bool_flag2("bool2", "", true);
-
-  xbt_test_add("Parse values");
-  xbt_cfg_set_parse("int:42 string:bar double:8.0 bool1:true bool2:false");
-  xbt_test_assert(int_flag == 42, "Check int flag");
-  xbt_test_assert(string_flag == "bar", "Check string flag");
-  xbt_test_assert(double_flag == 8.0, "Check double flag");
-  xbt_test_assert(bool_flag1, "Check bool1 flag");
-  xbt_test_assert(not bool_flag2, "Check bool2 flag");
-
-  xbt_cfg_free(&simgrid_config);
-  simgrid_config = temp;
-}
-
-#endif                          /* SIMGRID_TEST */