GitS Shell (WIP)

A custom C++ Unix shell and REPL featuring a raw-mode terminal engine, dynamic multiline navigation, and integrated Git repository tracking.

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🏛️ Project Architecture & Modular Design

The codebase utilizes a clean, decoupled design pattern separating blueprints (.hpp) from logical implementations (.cpp). To prevent global symbol pollution, everything is encapsulated within the Shell:: namespace tree.

Component Module	Namespace	Core Responsibilities
BuiltIn	Shell::BuiltIn	Manages process state mutations like workspace switching (cd), hardware path queries (pwd), and history flushing.
Core	Shell::Core	Houses the centralized hash table command registry engine, tokenization pipelines, and external subsystem execution blocks (fork/execvp).
Terminal	Shell::Terminal	Controls low-level terminal TTY hardware flags (termios) for raw unbuffered keyboard ingestion, custom row-wrapping metrics, and signal parsing.
History	Shell::History	Handles disk persistence state management by reading and updating interactive operational log caches.

Directory Tree Overview

├── src/
│   ├── BuiltIn.hpp          # Blueprints for internal core commands (cd, pwd, clear)
│   ├── BuiltIn.cpp
│   ├── Core.hpp             # Pipeline structs, tokenization, and command routing engines
│   ├── Core.cpp             # Splitting logic for operators (| , > , < , >>)
│   ├── Terminal.hpp         # Unbuffered key parsing and raw terminal state toggles
│   ├── Terminal.cpp         # Custom TTY manipulation via termios zero-latch
│   ├── History.hpp          # Read/Write streams for persistent terminal operational logs
│   ├── History.cpp
│   └── main.cpp             # Global REPL loop execution block and raw mode manager
├── .gitignore               # Excludes binary footprints (gits) and build/ artifacts
├── Makefile                 # Automated build directives compilation matrix
└── README.md                # Project architecture overview and future roadmap

🛠️ Core Features

• Raw Mode Engine: Bypasses standard line buffering (ICANON) and automatic echoing (ECHO) via termios to intercept raw keystrokes (getchar()) in real-time.
• Smart Multiline Wrapping: Queries terminal columns dynamically via ioctl to keep the physical cursor synchronized with the internal input buffer during wraps.
• Surgical Ctrl+C Aborts: Overrides kernel signals to cleanly scrub only the active input lines using terminal escape codes (\33[K, \33[A) without altering scrollback history.
• Process Isolation: Spawns external binaries inside a safe, isolated fork() and execvp() pipeline, temporarily suspending raw mode during execution.
• Git Awareness: Automatically monitors directory paths for local .git footprints to attach real-time repository context tags to the prompt.

⚙️ Build & Run

Build the shell

make

Launch the shell

./gits