cpp_logger_assignment/Logger.hpp

#ifndef LOGGER_HPP
#define LOGGER_HPP


#include <sys/types.h>
#include <pwd.h>

#include <ctime>

#include <ostream>
#include <sstream>

#include "Singleton_DCLP.hpp"

class Logger : public Singleton_DCLP<Logger>
{
public:
	class Endl {};

	Logger() :
		m_os(nullptr),
		m_buffer(),
		m_print_time_stamp(false),
		m_print_user_name(false) {}

	void setStream(std::ostream* os) { m_os = os; }

	void setPrintTimeStamp(bool b = true) { m_print_time_stamp = b; }
	void setPrintUserName(bool b = true) { m_print_user_name = b; }

	template <class T>
	Logger &operator<<(const T &x) {
		m_buffer << x;
		return *this;
	}

	Logger& operator<<(const Logger::Endl& e) {
		decorate();
		*m_os << m_buffer.str();
		*m_os << std::endl;
		m_buffer.str("");
		return *this;
	}

private:
	void decorate()
	{
		if (m_print_time_stamp) {
			const std::time_t timenow = std::time(nullptr);
			std::string s(std::ctime(&timenow));
			s.pop_back(); // removing trailing \n
			*m_os << s << " ";
		}
		if (m_print_user_name) {
#ifdef linux
			const uid_t uid = getuid();
			const struct passwd* p = getpwuid(uid);
			*m_os << p->pw_name << " ";
#elif _win32
			*m_os << "n00b ";
#endif
		}
	}

	// ostreams are not copyable, hence storing a pointer only
	std::ostream* m_os;
	std::ostringstream m_buffer;
	bool m_print_time_stamp;
	bool m_print_user_name;
};

#define LOG *Logger::getInstance()
#define END Logger::Endl();

#endif // LOGGER_HPP