HTTP Server from scratch written in c

This is a personal project that I started during the winter break, the goal is to learn more about linux, network, filesystem, etc..., and also learn c.

What?

This project is a lightweight HTTP/1.1 web server written in pure C. It is designed to handle multiple simultaneous client connections efficiently using a combination of non-blocking I/O, epoll, and multithreading.

Performance

You can check out more in detailed on how this server has been built and the performances (compared with nginx on the same machine) here: docs.pdf

Build

Requires:

• Linux or macOS
• GCC or Clang
• POSIX environment

Compile everything with gcc -O2 -g -fno-omit-frame-pointer -pthread src/**/*.c -Iinclude -lmagic -o my_server

By default the server listens on http://localhost:8080

Architecture Overview

The server is split into layers:

• OS
  • Read/Write raw bytes
• TCP
  • Accepts connections
• Buffer
  • Manage partial reads-write safely
• HTTP parser
  • Converts raw bytes into http_request_t
  • Parse request line
• Router
  • Decides how to handle requestlayer
  • Static file vs 404 (and later I hope, api)

Limitations

• no HTTPS
• No chunked transfer encoding
• no keep-alive (connection are closed after the response)
• Single threaded, blocking I/O

Possible improvements

• HTTP headers parsing
• POST request & body parsing
• keep-alive support
• epoll / non-blocking I/O
• thread pool
• Directory listing
• Basic api endpoints
• IPv6 support
• Security hardening (needed)