🧠 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.

---

📂 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

---

🚀 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/.

---

💬 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.

---

📡 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.

---

🧵 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().

---

🧰 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.

---

⚙️ 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.

---

🧩 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.

---

🧠 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

---

🪶 License

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

---

✨ Author

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