Can We Write a Web Application in C?

While it might seem unconventional to develop a web application using C, it is indeed possible. In this article, we'll explore the feasibility of writing web applications using C, highlighting existing libraries and modern approaches that make it viable.

Existing Solutions and Libraries

There are several libraries and frameworks available in C that make it possible to build both web servers and web applications. CTemplate by Google, for instance, is a highly fast templating library. Similarly, the SimpleWebServer is a powerful HTTP and HTTPS library that supports asynchronous operations.

Modern Web Development in C

For a more modern approach to web development, opting for Rust-based frameworks is highly recommended. Actix-Web is particularly notable for its performance and security features. The Yew library, when used for WebAssembly (WASM) front-ends, minimizes the need for JavaScript, making it an excellent choice for your web applications.

Actix, for instance, is one of the fastest web servers available, regardless of the programming language used. This is particularly relevant based on the TechEmpower Framework Benchmarks.

Complex Front-End Development in C

For more intricate frontend development, consider using the Godot Game Engine with some custom C extensions that are exported to HTML5. The glue logic, however, can be managed using Godot's scripting language, GDScript, which is very Python-like. This approach can be effective for developing rich frontend applications.

Browser Requirements and Challenges

Creating a web browser requires a deep understanding of various components. For C developers, some of the essential components include:

A JavaScript engine that runs WebAssembly and supports TypeScript wherever possible A rendering engine that handles layout, compositing, and painting to the screen An HTML parser that converts HTML into an Abstract Syntax Tree A Content Security Policy (CSP) system to ensure security

Developing these components from scratch in C can be a daunting task. Instead, studying the source code of popular browsers like Chromium, WebKit, and Firefox can provide valuable insights into how these components are implemented.

While it is possible to build a browser using C, it requires significant expertise and resources. I have written four browsers on my own since 2002, and the process involves understanding various widget sets and libraries. Here are some key points:

NCSA Mosaic and its variants provided the foundation for many modern widget sets, including those used in Internet Explorer and Edge. Chromium, Google Chrome, and other browsers use the WebKit API, a customized version of NCSA Mosaic's widget set. Mozilla Firefox uses the Gecko library, which has been customized over time.

Gecko, Wx, Qt, Tk, and GTK are known for their ability to render HTML and manage widgets. Among these, Tk has been particularly useful, as it has supported over 50 working browsers until around 2009. Projects like Mozilla and Chrome have successfully utilized these frameworks.

Challenges and Solutions

Building a browser in C involves complex tasks such as handling CSS and JavaScript after rendering. This process requires:

A master programmer skilled in regular expressions Proper HTML and CSS parsing Efficient methods for fetching and processing CSS, images, media, and JavaScript files Advanced rendering engines to combine HTML, CSS, and JavaScript effectively

While it is possible to build these components in C, it often requires a significant investment in time and resources. The process involves building comprehensive libraries to handle display and layout, as well as custom logic to handle CSS rules and JavaScript operations.

Conclusion: While developing a web application in C can be challenging, it is not impossible. Libraries like CTemplate, SimpleWebServer, and Actix-Web provide a strong foundation for building web applications in C. However, for more complex projects, considering modern frameworks like Rust and WebAssembly can significantly ease the development process.