C++ Virtual File System

Overview

C++ Virtual File System is a C++ project that implements a virtual file system based on i-nodes. The system simulates common file and directory operations in an environment that closely mimics real-world file systems. It is designed with modularity and extensibility in mind, making it easy to manage files, directories, and additional advanced operations.

Features

• Virtual File System Simulation: Implements core file system functionalities using i-nodes.
• Basic Operations: Supports file copy (cp), move/rename (mv), and deletion (rm).
• Directory Management: Create (mkdir), remove (rmdir), list (ls), and navigate directories (cd, pwd).
• File Operations: View file contents (cat), display file/directory metadata (info), and execute command sequences (load).
• Import/Export: Transfer files between the virtual file system and the physical disk using incp and outcp.
• Formatting: Initialize or reformat the virtual file system with a specific size using format.
• Advanced Options: Additional support for hard links, symbolic links, file concatenation, and file shortening.

Requirements

• A modern C++ compiler (e.g., g++)
• Make utility
• Linux environment (or WSL on Windows)

Installation and Compilation

To compile the project, ensure that you have g++ and make installed. You can install them with the following command:

sudo apt-get install g++ make -y

Once the prerequisites are installed, navigate to the project directory and run:

make

This will compile the project using the target name SemestralWork defined in the Makefile.

Usage

After successful compilation, start the virtual file system with:

./SemestralWork [path_to_virtual_disk]

Replace [path_to_virtual_disk] with the path to the file that will serve as the virtual disk. If the specified file does not exist, it will be created automatically. Note that before performing any file operations, you must initialize the file system using the format command.

Then you will need to format you file system (for example, only 10 megabytes):

format 10M

Supported Commands

The virtual file system accepts both absolute and relative paths and provides the following commands:

• cp s1 s2
  Copy file s1 to location s2.

• mv s1 s2
  Move or rename file s1 to s2.

• rm s1
  Remove file s1.

• mkdir a1
  Create a new directory a1.

• rmdir a1
  Remove an empty directory a1.

• ls [directory]
  List the contents of the specified directory. If no directory is specified, the current directory is listed.

• cat s1
  Display the contents of file s1.

• cd a1
  Change the current directory to a1.

• pwd
  Display the current working directory.

• info s1 or info a1
  Display metadata (such as size, i-node number, and direct/indirect links) for the specified file or directory.

• incp s1 s2
  Import a file from the physical disk (s1) into the virtual file system at location s2.

• outcp s1 s2
  Export a file from the virtual file system (s1) to the physical disk at location s2.

• load s1
  Execute a series of commands from file s1 (one command per line).

• format [size]
  Format the virtual file system to the specified size. Any existing data will be overwritten or a new file will be created if it does not exist.

Use the help command within the system to list all available commands and their usage details.

Project Structure

• Utils: Contains helper functions for file operations and string manipulation.
• Constants: Defines global constants, command strings, and error messages.
• Inode: Manages the i-node structure representing files and directories.
• DirectoryItem & Directory: Handle individual directory entries and overall directory structures.
• Superblock: Stores essential metadata and layout information for the virtual file system.
• VirtualFileSystem: Implements the core logic and operations of the file system.
• CommandProcessor: Interprets and executes user commands.
• Main: Entry point for initializing the system and starting the command loop.

Additional Notes

• Ensure that the virtual disk file is properly formatted before use to prevent instability or data loss.
• Always exit the application using exit or quit to guarantee that all changes are correctly saved.
• The system supports advanced features like hard links and symbolic links, which behave similarly to their real-world counterparts.

License

MIT License

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Happy C++ coding and using this virtual file system!