42 C Projects

A collection of projects from the 42 school cursus, spanning the common core C curriculum and a handful of smaller mini-games and coding exercises. The common-core work covers the foundations expected of every 42 student: building a libc from scratch, parsing and graphics, Unix processes, shells, concurrency, and even raw assembly. The mini-games gather exam-style algorithm puzzles and interpreters. Almost everything is written in C and built on a hand-rolled libft.

Common Core

Project	Summary
Extended libft C library	My extended 42 libft, rebuilt from scratch plus a custom toolkit: buffer-tracking ft_malloc/ft_free/ft_realloc, get_next_line, and 2D-array helpers.
Per-call file line reader	Hands back one newline-terminated line per call from a file descriptor, with string helpers I wrote from scratch. The bonus juggles up to 256 fds at once via a static save[256][BUFFER_SIZE+1].
Custom printf with multiple outputs	My own take on printf, shipped as libftprintf.a. I pushed past the assignment with three entry points: ft_printf to stdout, ft_dprintf to any fd, and ft_sprintf returning a heap string.
Two-stack integer sorter	My take on the push_swap challenge: sorting integers across two stacks with a minimal restricted op set, using a cost-based greedy chunk sort that scores each element's cheapest rotation path. Ships with a bonus checker binary.
MiniLibX collect-and-exit tile game	A MiniLibX 2D tile game on grid maps from .ber files: grab every collectible, then head for the exit. I went past the subject with enemy monsters and a flood-fill validator that proves the level is solvable before launch.
Wolfenstein-style raycasting engine	My Wolfenstein-style raycasting engine in MiniLibX: it parses a .cub scene file and renders a real-time textured 3D maze with DDA ray-grid traversal. I love how paranoid the map parser is.
Arbitrary-length shell pipeline emulator	My take on the shell pipeline: each command in ./pipex infile cmd1 cmd2 outfile gets its own forked child wired with anonymous pipes, and I pushed past the mandatory two to chain any number of pipes.
AST tree-walking Bash clone	A from-scratch Bash clone I'm proud of: it lexes input, builds a weighted AST of pipes, &&, ||, and subshells, then tree-walks it, forking with pipe/dup2 while running built-ins in-process.
Improved operator-precedence Bash shell	My improved, more-powerful minishell: it lexes input, builds an operator-precedence AST for |, &&, ||, ; and subshells, then forks/execs with full redirection, heredoc, expansion, and nine built-ins.
Dining Philosophers concurrency simulation	My take on Dining Philosophers, built twice (threads + mutexes, then forked processes over POSIX semaphores), where the hard part is grabbing two forks without ever deadlocking before time_to_die.
x86-64 libc assembly library	My own libc routines hand-written in x86-64 NASM (libasm.a), down at the syscall/register level, including an atoi_base built from scratch with full base validation.
Tracking malloc/free garbage collector	A drop-in malloc/free replacement backed by a garbage collector: every ft_malloc becomes a node in a linked list, so one destroy_garbage() tears it all down at once.

Mini-Games

Project	Summary
Biggest-square map solver	My "Biggest Square" solver finds the largest obstacle-free square in an ASCII map, using a precomputed summed-area table for O(1) candidate checks.
Single-file Brainfuck interpreter	My exam-style Brainfuck interpreter in a single brainfuck.c: it runs all 7 ops over a 2048-byte tape and skips the jump table entirely, resolving loops by scanning for the matching bracket.
Recursive bracket-balance checker	I check whether every argument's (), [], {} are balanced and nested: no explicit stack, just a self-recursive function walking a shared index, with write() as my only allowed syscall.
LeetCode 79 Word Search solver	My take on LeetCode 79 "Word Search": a backtracking DFS over a 2D grid, with a twist I'm proud of. It counts the word's first vs last char and launches from the rarer endpoint, searching forwards or backwards.