ConfigUtility now supports recursion; is a Singleton

If you have "config.next" set, the config system will load that as another
config file. Higher config files have a higher precedence over subfiles
when conflicting keys are encountered.

* Added singleton.hpp, containing Singleton<T>
* ConfigUtility now inherits from Singleton
* Tweaked timer.*pp layouts

common/utilities/config_utility.cpp

@@ -26,11 +26,22 @@
 #include <stdexcept>
 
 void ConfigUtility::Load(std::string fname) {
-	//TODO: recursive rerouting?
+	//clear the stored configuration
+	configMap.clear();
+	//pass to the recursive method
+	configMap = Read(fname);
+}
+
+ConfigUtility::table_t ConfigUtility::Read(std::string fname) {
+	//read in and return this file's data
+	table_t retTable;
 	std::ifstream is(fname);
 
 	if (!is.is_open()) {
-		throw(std::runtime_error("Failed to open config file"));
+		std::string msg;
+		msg += "Failed to open a config file: ";
+		msg += fname;
+		throw(std::runtime_error(msg));
 	}
 
 	std::string key, val;
@@ -71,35 +82,48 @@ void ConfigUtility::Load(std::string fname) {
 		}
 
 		//save the pair
-		table[key] = val;
+		retTable[key] = val;
 	}
 
 	is.close();
+
+	//load in any subordinate config files
+	//TODO: Possibility of nesting config levels?
+	if (retTable.find("config.next") != retTable.end()) {
+		table_t subTable = Read(retTable["config.next"]);
+		retTable.insert(subTable.begin(), subTable.end());
+	}
+
+	return retTable;
 }
 
+//-------------------------
+//Convert to a type
+//-------------------------
+
 std::string& ConfigUtility::String(std::string s) {
-	return table[s];
+	return configMap[s];
 }
 
 int ConfigUtility::Integer(std::string s) {
-	std::map<std::string, std::string>::iterator it = table.find(s);
-	if (it == table.end()) {
+	table_t::iterator it = configMap.find(s);
+	if (it == configMap.end()) {
 		return 0;
 	}
 	return atoi(it->second.c_str());
 }
 
 double ConfigUtility::Double(std::string s) {
-	std::map<std::string, std::string>::iterator it = table.find(s);
-	if (it == table.end()) {
+	table_t::iterator it = configMap.find(s);
+	if (it == configMap.end()) {
 		return 0.0;
 	}
 	return atof(it->second.c_str());
 }
 
 bool ConfigUtility::Boolean(std::string s) {
-	std::map<std::string, std::string>::iterator it = table.find(s);
-	if (it == table.end()) {
+	table_t::iterator it = configMap.find(s);
+	if (it == configMap.end()) {
 		return false;
 	}
 	return it->second == "true";

common/utilities/config_utility.hpp

@@ -22,14 +22,13 @@
 #ifndef CONFIGUTILITY_HPP_
 #define CONFIGUTILITY_HPP_
 
+#include "singleton.hpp"
+
 #include <map>
 #include <string>
 
-class ConfigUtility {
+class ConfigUtility : public Singleton<ConfigUtility> {
 public:
-	ConfigUtility() = default;
-	ConfigUtility(std::string s) { Load(s); }
-
 	void Load(std::string fname);
 
 	//convert to a type
@@ -39,16 +38,21 @@ public:
 	bool Boolean(std::string);
 
 	//shorthand
-	inline std::string& operator[](std::string s) { return String(s); }
+	inline std::string& operator[](std::string s) { return configMap[s]; }
 	inline int Int(std::string s) { return Integer(s); }
 	inline bool Bool(std::string s) { return Boolean(s); }
 
-	//OO breaker
-	std::map<std::string, std::string>* GetMap() {
-		return &table;
-	}
 private:
-	std::map<std::string, std::string> table;
+	typedef std::map<std::string, std::string> table_t;
+
+	friend Singleton<ConfigUtility>;
+
+	ConfigUtility() = default;
+	~ConfigUtility() = default;
+
+	table_t Read(std::string fname);
+
+	table_t configMap;
 };
 
 #endif

common/utilities/singleton.hpp

@@ -0,0 +1,63 @@
+/* Copyright: (c) Kayne Ruse 2014
+ * 
+ * This software is provided 'as-is', without any express or implied
+ * warranty. In no event will the authors be held liable for any damages
+ * arising from the use of this software.
+ * 
+ * Permission is granted to anyone to use this software for any purpose,
+ * including commercial applications, and to alter it and redistribute it
+ * freely, subject to the following restrictions:
+ * 
+ * 1. The origin of this software must not be misrepresented; you must not
+ * claim that you wrote the original software. If you use this software
+ * in a product, an acknowledgment in the product documentation would be
+ * appreciated but is not required.
+ * 
+ * 2. Altered source versions must be plainly marked as such, and must not be
+ * misrepresented as being the original software.
+ * 
+ * 3. This notice may not be removed or altered from any source
+ * distribution.
+*/
+#ifndef SINGLETON_HPP_
+#define SINGLETON_HPP_
+
+#include <stdexcept>
+
+template<typename T>
+class Singleton {
+public:
+	static T& GetSingleton() {
+		if (!ptr) {
+			throw(std::logic_error("This singleton has not been created"));
+		}
+		return *ptr;
+	}
+	static void Create() {
+		if (ptr) {
+			throw(std::logic_error("This singleton has already been created"));
+		}
+		ptr = new T();
+	}
+	static void Delete() {
+		if (!ptr) {
+			throw(std::logic_error("A non-existant singleton cannot be deleted"));
+		}
+		delete ptr;
+		ptr = nullptr;
+	}
+
+protected:
+	Singleton() = default;
+	Singleton(Singleton const&) = default;
+	Singleton(Singleton&&) = default;
+	~Singleton() = default;
+
+private:
+	static T* ptr;
+};
+
+template<typename T>
+T* Singleton<T>::ptr = nullptr;
+
+#endif