KlyLogger

A lightweight, color console and file logging library for C++.
一个支持彩色控制台输出和日志文件写入的轻量级 C++ 日志库.

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Platforms / 平台支持

• Windows (tested on Windows 7, Windows 10 and Windows 11)
• Linux (tested on Ubuntu and Kali)

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Usage / 使用示例

#include "KlyLogger.hpp"

int main() {
	// Initialize loggers / 初始化日志器
	KlyLogger logger; // Default logger / 默认日志器

	// Logging examples / 日志示例
	logger.info(L"Application started: {}", L"MyApp");

	std::string user = "Lucy";
	std::wstring action = L"logged in";
	logger.info("User {} {}", user, action); // Mixed string and wstring / string 与 wstring 混用

	logger.warn(L"Low memory warning: {} MB left", 100);
	logger.error(L"File not found: {}", "config.txt");
	logger.fatal(L"Unexpected crash!");

	// Minecraft-style colored output / Minecraft 风格彩色字符示例
	// Example: §c red, §a green, §e yellow, §b aqua, §f white, §5 purple
	KlyLogger("Colorful").info(L"§c红色 §a绿色 §e黄色 §b水蓝色 §f白色 §5紫色");

	return 0;
}

Key Features / 主要功能

• Thread-safe operations / 多线程安全操作
• Color-coded console output / 控制台彩色输出
• Supports logging to both console and file / 同时支持控制台和文件日志
• Default and named logger objects ready-to-use / 提供默认和自定义名称日志器, 开箱即用
• Easy-to-use API with std::format style formatting / 提供 std::format 风格的简单易用 API
• Supports Minecraft-style color codes in console output / 支持类似 Minecraft 的彩色字符输出
• Supports multiple log levels: info, warn, error, fatal / 支持多种日志等级：info, warn, error, fatal
• Supports mixed usage of std::string and std::wstring for logging / 支持 std::string 与 std::wstring 混合使用
• All log files are automatically stored under the logs folder located beside the executable, not in the working directory / 所有日志文件会自动保存到 程序所在位置 （非工作目录）下的 logs 文件夹中

  ⚠️ Note: Using std::string with non-ASCII characters is not recommended to avoid decoding issues.

  ⚠️ 注意：不建议在 std::string 中使用非 ASCII 字符, 避免解码出现乱码

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Configuration / 配置选项

You can control KlyLogger's behavior using the following preprocessor macros:
在引入 KlyLogger.hpp 之前定义以下预处理宏可调整 KlyLogger 的行为:

• KLY_LOGGER_OPTION_NO_LOG_FILE
  Disable log file output.
  禁用日志文件输出.

• KLY_LOGGER_DISABLE_EXTERN_RTL_GET_VERSION
  Prevent duplicate definition of RtlGetVersion (used internally by KlyLogger from ntdll.dll ).
  防止 RtlGetVersion 函数重复定义 (KlyLogger 内部使用该函数指向 ntdll.dll ).

• KLY_LOGGER_OPTION_NO_CACHE_FOR_OUTPUT_HANDLE
  Disable caching of output handles, useful for programs that dynamically change console handles.
  禁用输出句柄缓存, 适用于动态改变控制台句柄的程序.
  Example / 示例:

  #define KLY_LOGGER_OPTION_NO_CACHE_FOR_OUTPUT_HANDLE
  #include "KlyLogger.hpp"
  ...
  
  FreeConsole();
  AttachConsole(getParentProcessId());
  
  // If KLY_LOGGER_OPTION_NO_CACHE_FOR_OUTPUT_HANDLE is not defined,
  // logger output may not appear after reattaching the console.
  // 如果没有定义 KLY_LOGGER_OPTION_NO_CACHE_FOR_OUTPUT_HANDLE,
  // 那么在 attachConsoleToParent() 之后可能看不到日志输出.
  KlyLogger logger;
  logger.info(L"Console reattached successfully!");

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Inspiration / 灵感来源

The log output format of KlyLogger was inspired by PaperMC , a well-known Minecraft server project.
The color scheme and visual style were then customized to my own preference.
This project also marks my first step into modern C++ development.

KlyLogger 的日志输出格式灵感来自知名的 Minecraft 服务器项目 PaperMC , 并在此基础上根据个人喜好进行了颜色与视觉样式的改进.
同时, 这也是本人踏入现代化 C++ 开发的入门作品.

View the code on GitHub.