Hydrogen - very composable c interfaces

In some Languages you have Mixins which help you to devide problems into generic interfaces and their implementations. This allows easier code reuse and less complex code as a project evolves. I never found this functionality for C so thats what this library is trying to provide.

Installation

This is a very smal library. Just put hydrogen.h in your inclusion path. Than add hydrogen.c to the compiled files.

Idea

By providing a generic interface mechanism this library tries to adress several goals:

• Improve code resuability.

• Reduce of code complexity.

• Simpler, smaller and less changing header files.

• More portable libraries.

  • since it’s written in ANSI C you should be able to port it nearly everywhere.

  • because the interfaces created with it can be very generic and isolated of the implementations you should be able to port denending libraries nearly everywhere.

It introduces the struct h_vfs which serves as a generic class. Than it lets you define interfaces as sets of functions that a class can implement. All functions implementing such an interface get a first argument h_vfs *self. Since all classes use the same type a class can implement an arbitrary number of different interfaces without conflict.

References

Hydrogen is highly inspired by libdill where I first saw this technique (in fakt it is mostly extracted from there). However it serves a different purpose as its intended use is a general pupose c library for creating c interfaces and has no connection to concorrency or networking.

The name

Hydrogen is a very simple element with only one electron. It’s very light and easly composable with other elements to form molecules. It’s possible to get very much energy out of it (think of the sun, fuel cells or H-bombs) but use it with care …​