Systems Programming Portfolio in C

A curated collection of production-quality systems-level C projects demonstrating:

• Robust design patterns
• Clean separation of concerns
• Strong emphasis on testing and correctness
• Idiomatic and safe C style suitable for professional development

These projects highlight my ability to design, implement, and test low-level systems software—skills critical for roles in OS development, embedded systems, and performance-critical libraries.

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Included Projects

1. Process Scheduler Simulator in C

• Discrete-event simulation engine for modeling CPU scheduling
• Implements 8 classic and preemptive scheduling algorithms (FCFS, LCFS, SJF, PSJF, SRPT, PLCFS, PS, FB)
• Modular design with clear separation between simulator core and scheduling policy implementations
• Custom generic linked list with user-defined comparison for priority queues
• Thorough unit tests for linked list and full simulation runs with trace files

File: process-scheduler-simulator/

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2. pthread Concurrency Primitives

• Go-style channel implementation in pure C with POSIX threads
• Blocking and non-blocking channels with FIFO fairness
• select-style API supporting multiplexed waits across channels
• Robust stress tests simulating ring-passing and realistic topologies
• Portable design using semaphores, mutexes, and condition variables with no busy-polling

File: pthread-concurrency/

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3. Custom Dynamic Memory Allocator

• Manual implementation of malloc, free, realloc, and calloc
• Segregated free lists for fast allocation by size class
• Coalescing adjacent free blocks to reduce fragmentation
• Block splitting for internal space efficiency
• Debugging support with heap consistency checker

File: custom-malloc-allocator/

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4. Pointer Manipulation in C

• Demonstrates low-level memory and pointer manipulation
• Emulated polymorphism using function pointers and virtual function tables
• Generic data structures: sorted linked lists and explicit-iterator binary search trees
• Thoroughly tested with 50+ unit tests covering edge cases, traversal correctness, and aggregation
• Production-quality C patterns for reusable, modular design

File: pointer-manipulation/

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Key Skills Demonstrated

• Systems-level C design with clean, idiomatic style
• Advanced concurrency and synchronization with pthreads
• Manual memory management with allocator strategies
• Emulation of OOP patterns in C (VFTs, polymorphism)
• Event-driven simulation modeling
• Generic data structure design and testing
• Strong emphasis on correctness, maintainability, and testing

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🛠️ Build & Test

Each project includes:

• Clean modular source structure
• Self-contained Makefile for build automation
• Unit tests and/or trace-based simulation verification

Purpose

This repository is designed to demonstrate real-world systems programming ability suitable for:

• Operating system internals
• Embedded or real-time systems
• Performance-critical C libraries
• Teaching and mentoring on professional C design patterns