Add logging library

libs/log/CMakeLists.txt

@@ -0,0 +1,8 @@
+find_package(Threads)
+
+file(GLOB_RECURSE PSEMEK_LOG_HEADERS RELATIVE "${CMAKE_CURRENT_SOURCE_DIR}" "include/*.hpp")
+file(GLOB_RECURSE PSEMEK_LOG_SOURCES RELATIVE "${CMAKE_CURRENT_SOURCE_DIR}" "source/*.cpp")
+
+add_library(log ${PSEMEK_LOG_HEADERS} ${PSEMEK_LOG_SOURCES})
+target_include_directories(log PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/include")
+target_link_libraries(log PUBLIC ${CMAKE_THREAD_LIBS_INIT})

libs/log/include/psemek/log/level.hpp

@@ -0,0 +1,27 @@
+#pragma once
+
+namespace psemek::log
+{
+
+	enum class level
+	{
+		debug,
+		info,
+		warning,
+		error,
+	};
+
+	template <typename Stream>
+	Stream & operator << (Stream & s, level l)
+	{
+		switch (l)
+		{
+		case level::debug: return s << "debug";
+		case level::info: return s << "info";
+		case level::warning: return s << "warning";
+		case level::error: return s << "error";
+		default: return s << "(unknown)";
+		}
+	}
+
+}

libs/log/include/psemek/log/log.hpp

@@ -0,0 +1,47 @@
+#pragma once
+
+#include <psemek/log/level.hpp>
+
+#include <string>
+#include <thread>
+#include <sstream>
+
+namespace psemek::log
+{
+
+	void set_max_thread_name_length(int length);
+
+	void register_thread(std::string name);
+	void register_thread(std::thread::id id, std::string name);
+
+	void put_message(level l, std::string const & message);
+
+	struct log_stream
+	{
+		log_stream(level l)
+			: l_(l)
+		{}
+
+		~log_stream()
+		{
+			put_message(l_, os_.str());
+		}
+
+		template <typename T>
+		log_stream & operator << (T const & x)
+		{
+			os_ << x;
+			return *this;
+		}
+
+	private:
+		level l_;
+		std::ostringstream os_;
+	};
+
+	inline log_stream debug() { return {level::debug}; }
+	inline log_stream info() { return {level::info}; }
+	inline log_stream warning() { return {level::warning}; }
+	inline log_stream error() { return {level::error}; }
+
+}

libs/log/source/log.cpp

@@ -0,0 +1,78 @@
+#include <psemek/log/log.hpp>
+
+#include <chrono>
+#include <ctime>
+#include <iostream>
+#include <sstream>
+#include <iomanip>
+#include <mutex>
+#include <unordered_map>
+#include <thread>
+
+namespace psemek::log
+{
+
+	static int max_thread_name_length = 5;
+
+	void set_max_thread_name_length(int length)
+	{
+		max_thread_name_length = length;
+	}
+
+	static std::unordered_map<std::thread::id, std::string> thread_names;
+
+	void register_thread(std::string name)
+	{
+		register_thread(std::this_thread::get_id(), std::move(name));
+	}
+
+	void register_thread(std::thread::id id, std::string name)
+	{
+		auto it = thread_names.find(id);
+		if (it != thread_names.end())
+			throw std::runtime_error("Thread \"" + name + "\" already registered!");
+
+		if (name.size() > max_thread_name_length)
+			throw std::runtime_error("Thread \"" + name + "\" name is too long");
+
+		thread_names[id] = name;
+
+		put_message(level::info, "Thread \"" + name + "\" registered");
+	}
+
+	static ::tm safe_localtime(std::time_t const & time)
+	{
+		static std::mutex mutex;
+		std::lock_guard lock{mutex};
+		return *std::localtime(&time);
+	}
+
+	void put_message(level l, std::string const & message)
+	{
+		static std::string unknown_thread_name = "???";
+
+		using clock = std::chrono::system_clock;
+
+		auto const time = clock::to_time_t(clock::now());
+		auto const tm = safe_localtime(time);
+
+		auto const millis = std::chrono::duration_cast<std::chrono::milliseconds>(clock::now().time_since_epoch()).count() % 1000;
+
+		auto const id = std::this_thread::get_id();
+		auto const it = thread_names.find(id);
+
+		auto const & thread_name = (it == thread_names.end()) ? unknown_thread_name : it->second;
+
+		std::ostringstream os;
+		os
+			<< '[' << std::put_time(&tm, "%Y %b %d  %H:%M:%S.") << std::setw(3) << std::setfill('0') << millis << ']'
+			<< '[' << std::setw(max_thread_name_length) << std::setfill(' ') << thread_name << ']'
+			<< '[' << std::setw(7) << l << ']'
+			<< ' ' << message;
+
+		static std::mutex cout_mutex;
+		std::lock_guard lock{cout_mutex};
+		std::cout << os.str() << std::endl;
+	}
+
+}

todo.md

@@ -4,5 +4,4 @@
 * Implement pixmap font rendering
 * Create a simple generic primive painter
 * Design resources system
-* Design logging system
 * Design ui system