Ctrl + Z - Version Control System

Table of Contents

• Description
• Objective
• Features
• How to Use
• Project Structure
• Technologies Used
• Contributors
• Future Enhancements

---

Description

Ctrl + Z is a custom version control system developed as a final project for the Operating Systems course. It allows users to manage repositories, track versions, collaborate with others, and securely store code with encryption. The system is implemented in C and provides a command-line interface for all operations.

---

Objective

The main objectives of this project are:

• To provide basic version control functionalities (push, pull, versioning, etc.).
• To enable collaboration among multiple users with configurable access control.
• To offer a simple, educational alternative to mainstream VCS tools like Git.
• To demonstrate OS-level concepts such as file management, threading, and synchronization.

---

Features

• User Authentication: Register, login, and logout with secure credential management.
• Repository Management: Create, browse, and publish repositories.
• Versioning: Push new versions, pull any previous version, and revert to older versions.
• Collaboration: Add or remove collaborators with fine-grained access control.
• Stats & Diff: Compare two versions of a repository and view detailed file differences.
• Encryption: Secure files using an encryption/decryption algorithm.
• Threaded Operations: Uses multithreading for efficient repository browsing and file comparison.
• Configurable Access: Public/private repositories and collaborator management via config files.
• Command-Line Interface: Interactive menu-driven CLI for all operations.

---

How to Use

1. Build the Project

   gcc -o main main.c -lpthread

2. Run the Program

   ./main

3. Main Menu Options

   • Browse public repositories
   • Register as a new user
   • Login/Logout
   • Publish your own repository
   • Push/pull files (with versioning)
   • Add/remove collaborators

4. Versioning

   • Each push creates a new Version_N folder in the repository.
   • Commit messages and history are tracked in History.txt.
   • Pull any version to any folder, or revert to a previous state.

5. Collaboration

   • Only authors and collaborators (as listed in Config.txt) can push/pull private repositories.
   • Public repositories can be browsed and pulled by anyone.

6. Encryption

   • Use the encryption algorithm to encrypt/decrypt files as needed.

---

Project Structure

ctrl-z/
│
├── main.c            # Main CLI and logic
├── auth.c            # User authentication and registration
├── stats.c           # Version comparison and diff stats
├── utils.c           # Utility functions (file copy with encryption/decryption, etc.)
├── version.c         # Versioning logic (push, pull, revert)
│
├── Ascii.txt         # ASCII art for UI
├── README.md         # Project documentation
├── .gitignore        # Ignore compiled binaries
└── .vscode/          # VSCode settings

---

Technologies Used

• Language: C (C17 standard)
• Libraries: POSIX (pthread, dirent, stdio, stdlib, string, sys/stat, unistd)
• Build Tool: GCC
• Editor: Visual Studio Code

---

Contributors

• Abdul Rafay Mughal
• Abdullah Azhar Khan
• Muhammad Awais Shaikh
• Syed Muhammad Shubair Hyder

---

Future Enhancements

• Add a graphical user interface (GUI).
• Implement more advanced difference and merge tools.
• Add support for remote repositories and networking.
• Improve encryption options and security.
• Add automated tests and CI/CD integration.

---

PS: This project is for educational purposes and demonstrates core OS and version control concepts in C.