CONFIGMAN: added defragmentation methods for one-plugin-at-a-time

One-plugin-at-a-time can have fragmentation caused by the ConfigManager if a game changes any configuration value. By reallocating and copying over the ConfigManager, we avoid this problem.

svn-id: r54243

base/main.cpp

@@ -408,6 +408,8 @@ extern "C" int scummvm_main(int argc, const char * const argv[]) {
 		#if defined(ONE_PLUGIN_AT_A_TIME) && defined(DYNAMIC_MODULES)
 			// do our best to prevent fragmentation by unloading as soon as we can
 			PluginManager::instance().unloadPluginsExcept(PLUGIN_TYPE_ENGINE, NULL, false);
+			// reallocate the config manager to get rid of any fragmentation
+			ConfMan.defragment();
 		#endif	
 			
 			// Did an error occur ?

common/config-manager.cpp

@@ -53,6 +53,27 @@ const char *ConfigManager::kKeymapperDomain = "keymapper";
 ConfigManager::ConfigManager() : _activeDomain(0) {
 }
 
+void ConfigManager::defragment() {
+	ConfigManager *newInstance = new ConfigManager();
+	newInstance->copyFrom(*_singleton);
+	delete _singleton;
+	_singleton = newInstance;
+}
+
+void ConfigManager::copyFrom(ConfigManager &source) {
+	_transientDomain = source._transientDomain;
+	_gameDomains = source._gameDomains;
+	_appDomain = source._appDomain;
+	_defaultsDomain = source._defaultsDomain;
+#ifdef ENABLE_KEYMAPPER
+	_keymapperDomain = source._keymapperDomain;
+#endif
+	_domainSaveOrder = source._domainSaveOrder;
+	_activeDomainName = source._activeDomainName;
+	_activeDomain = &_gameDomains[_activeDomainName];
+	_filename = source._filename;
+}
+
 
 void ConfigManager::loadDefaultConfigFile() {
 	// Open the default config file
@@ -596,7 +617,6 @@ bool ConfigManager::hasGameDomain(const String &domName) const {
 
 #pragma mark -
 
-
 void ConfigManager::Domain::setDomainComment(const String &comment) {
 	_domainComment = comment;
 }

common/config-manager.h

@@ -141,6 +141,9 @@ public:
 	const DomainMap &	getGameDomains() const { return _gameDomains; }
 	DomainMap &			getGameDomains() { return _gameDomains; }
 
+	static void			defragment();	// move in memory to reduce fragmentation
+	void 				copyFrom(ConfigManager &source);
+	
 private:
 	friend class Singleton<SingletonBaseType>;
 	ConfigManager();

common/singleton.h

@@ -39,8 +39,6 @@ private:
 	Singleton<T>(const Singleton<T> &);
 	Singleton<T> &operator=(const Singleton<T> &);
 
-	static T *_singleton;
-
 	/**
 	 * The default object factory used by the template class Singleton.
 	 * By specialising this template function, one can make a singleton use a
@@ -89,6 +87,8 @@ protected:
 #endif
 
 	typedef T	SingletonBaseType;
+	
+	static T *_singleton;
 };
 
 /**