XLog - Modular C++ Logging System

A lightweight, decoupled logging framework for C++ applications that follows the Strategy and Factory design patterns. This system allows for flexible log formatting and multiple output destinations through a simple interface.

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## Features

• Multi-Level Logging: Supports four distinct log levels: DEBUG, INFO, ERROR, and FATAL.
• Flexible Output Targets:
  • Console Output: Standard output logging via LogConsoleOutput.
  • File Output: Persistent logging to disk via LogFileOutput with configurable file paths.
• Pluggable Formatting: Uses a dedicated LogFormat interface to transform raw log data into structured strings.
• Configuration Driven: Dynamically switches log types (console/file), file names, and priority levels using an external .conf file.
• Macro-Based API: Provides easy-to-use macros that automatically capture the calling file name and line number.
• Memory Management: The Logger class handles the lifecycle of its delegate formatters and outputters.

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## Core Architecture

The system is built on a composition-based design:

1. Logger: The core engine that manages log levels and delegates work to the formatter and outputter.
2. LogFormat (Interface): Defines how the log message, level, file, and line number are stringified.
3. LogOutput (Interface): Defines where the formatted string is sent.
4. LogFac (Factory): A singleton class that manages the global logger instance and handles initialization from configuration files.

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## Quick Start

1. Configuration (log.conf)

Define your settings in a simple key-value format:

log_type=file
log_file=log.txt
log_level=info

#include "log_fac.h"

int main() {
    // Initialize with config file
    LogFac::Instance().init("log.conf");

    // Log messages
    LOGINFO("Application started.");
    LOGDEBUG("This will only show if log_level is debug.");
    LOGERROR("An unexpected error occurred.");

    return 0;
}

Roadmap & Future Enhancements

XML Formatting Support: Implementation of an XMLLogFormat class to allow logs to be parsed easily by automated tools.

Asynchronous Logging: Adding a thread-safe queue to prevent logging operations from blocking the main application thread.

Log Rotation: Support for rolling log files based on file size or time intervals.

Colored Console Output: Enhancing the LogConsoleOutput to support ANSI color codes for different log levels.