🧠 NetProbe

NetProbe is a lightweight C++ networking playground for exploring sockets, multicast, TCP servers/clients, lock-free queues, custom memory pools, and multithreaded programming — all wrapped with a minimal logging and timing utility.

It’s designed to help you understand and experiment with the low-level building blocks behind distributed systems, trading infrastructure, and networked applications.

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📂 Directory Structure

./
└── src/
    ├── chat_client.cpp         # Simple TCP chat client
    ├── chat_server.cpp         # Broadcast chat server using epoll
    ├── lf_queue_example.cpp    # Lock-free queue producer-consumer demo
    ├── logging_example.cpp     # Logging utility showcase
    ├── mcast_publisher.cpp     # Multicast publisher sending random ticks
    ├── mcast_socket.cpp        # Multicast socket abstraction
    ├── mcast_subscriber.cpp    # Multicast subscriber that prints incoming ticks
    ├── mem_pool_example.cpp    # Memory pool allocator example
    ├── socket_example.cpp      # TCP server-client interaction example
    ├── tcp_server.cpp          # Epoll-based TCP server core
    ├── tcp_socket.cpp          # TCP socket abstraction
    └── thread_example.cpp      # Thread utility and example

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🚀 Getting Started

🛠️ Build

Make sure you have CMake ≥ 3.16 and a C++20 compiler.

mkdir build && cd build
cmake ..
make -j

This will generate all example executables inside build/src/.

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💬 Chat Example

1️⃣ Start the Chat Server

./chat_server

Logs to: chat_server.log

2️⃣ Start one or more Clients

./chat_client

Each client can send messages that are broadcast to all others.
Type /quit to exit.

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📡 Multicast Example

Start Subscriber

./mcast_subscriber

Start Publisher

./mcast_publisher

The publisher sends random ticks (e.g. TICK|AAPL|145.67) to a multicast group (239.192.1.1:5001), and all subscribers receive them in real-time.

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🧵 Threading & Concurrency

Lock-Free Queue

./lf_queue_example

Demonstrates a single-producer/single-consumer lock-free queue where one thread writes and another reads data asynchronously.

Memory Pool

./mem_pool_example

Custom memory pool that allocates and deallocates fixed-size objects efficiently, avoiding frequent heap allocations.

Thread Utilities

./thread_example

Demonstrates spawning and managing threads using the helper createAndStartThread().

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🧰 Logging Example

./logging_example

Logs various data types to logging_example.log using the custom Logger class:

logger.log("Logging a char:% an int:% and an unsigned:%\n", c, i, ul);

Each log entry is timestamped with nanosecond precision.

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⚙️ Socket Example

./socket_example

Spins up a local TCP server and multiple clients that exchange messages through the event loop.
Useful for understanding the flow of sendAndRecv(), non-blocking I/O, and epoll event handling.

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🧩 Core Components Overview

Component	Description
Logger	Lightweight file logger with formatted log support.
TCPSocket / TCPServer	Abstractions for non-blocking TCP communication using epoll.
McastSocket	Multicast socket layer for market data distribution / pub-sub systems.
LFQueue	Lock-free queue for high-performance producer-consumer workloads.
MemPool	Fixed-size memory allocator for deterministic allocations.
ThreadUtils	Helper utilities for spawning and managing named threads.

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🧠 Learnings & Focus Areas

• Non-blocking I/O with epoll
• TCP vs Multicast communication
• Lock-free concurrency primitives
• Efficient memory management
• Logging, tracing, and profiling for network systems
• Thread orchestration and data synchronization

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🪶 License

This project is licensed under the MIT License — feel free to use, modify, and share.

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✨ Author

Souvik Mukherjee
💼 Analyst SWE @ Zanskar Research
🚀 Building trading infrastructure, OMS/ORMS modules, and low-latency systems in C++
📫 LinkedIn