Draft: Persistent fuzzing example

[Teufelchen1]

Hi 🧇

This shows a low effort, cheap & dirty fuzzing harness for AFL++ in persistent mode.
It is based on the pretty-printer example. I removed the prints for speed-up. Additionally guards/limits were necessary to prevent hangs / stack overflows due to recursion.

Interesting settings to play with:

• Instead / inadditon of ASAN, try MSAN or UBSAN
• Instead of 1024 byte input limit, try more (needs beefy cpu / configuration to prevent AFL from collecting hangs)
• Change the max-depth limits of _parse_cbor and _parse_map

to compile:

cd tests/fuzz
AFL_USE_ASAN=1 afl-clang-fast main.c ../../src/*.c -I ../../include/

to fuzz"

afl-fuzz -i inputs/ -o findings/ -- ./a.out

(this draft is a result of my procrastination - I have no intentions of putting it in shape to make it merge'able)