📚 Libft

A custom implementation of essential C standard library functions, developed as part of the 42 School curriculum. This project serves as a foundational toolkit for future C programming projects, providing a deep understanding of low-level memory management, string manipulation, and data structures.

---

📖 Overview

Libft is a personal recreation of commonly used functions from the standard C library (libc), along with additional utility functions. The goal is to build a reusable library that can be used across multiple projects.

This project focuses on:

• Rewriting standard C functions from scratch
• Understanding how fundamental operations work internally
• Building reliable, reusable code
• Learning proper memory management and debugging techniques

---

🧠 Learning Objectives

By completing this project, you will gain experience with:

• Low-level memory manipulation
• String handling and processing
• Pointer arithmetic
• Dynamic memory allocation (malloc, free)
• Linked list implementation
• Code modularity and reusability
• Writing clean and maintainable C code

---

📂 Project Structure

libft/
├── ft_*.c        # Core library functions
├── ft_*.h        # Header file(s)
├── Makefile      # Build system
└── README.md

The project typically includes:

• Part 1: Reimplementation of standard libc functions
• Part 2: Additional utility functions
• Bonus: Linked list manipulation functions

---

🔧 Core Functions

🔹 Memory Functions

• ft_memset
• ft_bzero
• ft_memcpy
• ft_memmove
• ft_memchr
• ft_memcmp

---

🔹 String Functions

• ft_strlen
• ft_strdup
• ft_strcpy / ft_strlcpy
• ft_strcat / ft_strlcat
• ft_strchr / ft_strrchr
• ft_strncmp
• ft_substr
• ft_strjoin
• ft_split
• ft_strtrim

---

🔹 Character Checks & Conversions

• ft_isalpha
• ft_isdigit
• ft_isalnum
• ft_isascii
• ft_isprint
• ft_toupper
• ft_tolower

---

🔹 Conversion Functions

• ft_atoi
• ft_itoa

---

🔹 Output Functions

• ft_putchar_fd
• ft_putstr_fd
• ft_putendl_fd
• ft_putnbr_fd

---

🌟 Bonus Part — Linked Lists

Implementation of a simple singly linked list structure:

typedef struct s_list
{
    void            *content;
    struct s_list   *next;
} t_list;

Linked List Functions

• ft_lstnew
• ft_lstadd_front
• ft_lstsize
• ft_lstlast
• ft_lstadd_back
• ft_lstdelone
• ft_lstclear
• ft_lstiter
• ft_lstmap

---

⚙️ Compilation & Usage

To build the library:

make

This will generate:

libft.a

Cleaning

make clean      # Remove object files
make fclean     # Remove object files + library
make re         # Rebuild everything

---

🚀 How to Use

1. Include the header in your project:

#include "libft.h"

2. Compile your program with the library:

gcc main.c libft.a -o program

---

🧪 Example

#include "libft.h"
#include <stdio.h>

int main(void)
{
    char *str = ft_strdup("Hello, Libft!");
    printf("%s\n", str);
    free(str);
    return 0;
}

---

📌 Requirements

• C compiler (example: GCC, clang)
• Make
• UNIX-based system (Linux/macOS recommended)

---

🎯 Key Concepts Covered

Category	Topics
Memory Management	Allocation, deallocation, raw memory ops
Strings	Manipulation, parsing, transformation
Data Structures	Linked lists
Low-Level C	Pointers, buffers, manual control
Code Design	Modularity and reusable libraries

---

🚀 Purpose of the Project

The Libft project is designed to:

• Build a strong foundation in C programming
• Understand how standard library functions work internally
• Create a reusable library for future projects
• Improve debugging and problem-solving skills

---

⚠️ Notes

• All functions are implemented from scratch (no direct use of libc equivalents)
• Pay close attention to memory leaks and edge cases
• Follow coding standards (e.g., 42 Norm if applicable)

---

🤝 Contributing

Contributions and improvements are welcome!

1. Fork the repository
2. Create a feature branch
3. Submit a pull request

---

📄 License

This project is for educational purposes. Refer to the repository for licensing details (if provided).

---

📚 Resources

To deepen your understanding:

• C standard library documentation
• Manual pages (man malloc, man strlen, etc.)
• Memory management guides
• Data structures and algorithms basics

---