Inject logger instead of using a singleton

src/logger.cpp

@@ -1,32 +1,35 @@
 #include <cstdio>
 #include "logger.hpp"
 
+void Log(std::string const & label, std::string const & message)
+{
+	std::printf("[%s] %s\n", label.c_str(), message.c_str());
+}
+
+void Logger::Success(const std::string & s)
+{
+	Log("SUCCESS", s);
+}
+
+void Logger::Error(const std::string & s)
+{
+	Log("ERROR", s);
+}
+
+void Logger::Info(const std::string & s)
+{
+	Log("INFO", s);
+}
+
+void Logger::Debug(const std::string & s)
+{
+	Log("DEBUG", s);
+}
+
 Logger::~Logger()
 {
 }
 
 Logger::Logger()
 {
-}
-
-void Logger::Success(const std::string & s)
-{
-	std::printf("[SUCCESS] %s\n", s.c_str());
-}
-
-void Logger::Error(const std::string & s)
-{
-	std::printf("[ERROR] %s\n", s.c_str());
-}
-
-void Logger::Info(const std::string & s)
-{
-	std::printf("[INFO] %s\n", s.c_str());
-}
-
-Logger & Logger::GetInstance()
-{
-	static Logger logger;
-
-	return logger;
 }