libsigrokdecode (sometimes abbreviated as "srd") is a shared library written in C, which provides (streaming) protocol decoding functionality.
It is licensed under the terms of the GNU GPL, version 3 or later.
The protocol decoders are written in Python 3.
Getting the code
$ git clone git://sigrok.org/libsigrokdecode
You can also browse the source code via gitweb.
Building from source
Supported protocol decoders
The libsigrokdecode library ships with a collection of various protocol decoders out of the box (but you can write your own too, of course; see Protocol decoder HOWTO and Protocol decoder API for details).
See Protocol decoders for the list of currently supported ones (and others we might support in the future).