Libcanard v0 dsdl_compiler .uavcan to .h

What is the command to generate .h for libcanard v0?

There is no DSDL compiler for Libcanard v0.

I found it in ardupilot.

If you are using DSDL types with @union, pay attention to a small bug in the compiler that I found. In Se below. I noticed this because the tag size was not calculated correctly…

Row 330:
t.union = len(t.fields).bit_length()

I needed to change to
t.union = (len(t.fields)-1).bit_length()

Row 341-344:

if t.request_union:
        t.request_union = len(t.request_fields).bit_length()
  if t.response_union:
       t.response_union = len(t.response_fields).bit_length()

I changed to

if t.request_union:
    t.request_union = (len(t.request_fields)-1).bit_length()
if t.response_union:
    t.response_union = (len(t.response_fields)-1).bit_length()

While we’re at it, there is far more than one bug in that compiler, which is why we pulled it from upstream wholesale.

What is the suggested way to do this nowadays?

It mostly depends on your objectives. What are you building and what are the requirements? What programming language you are using? Where the end product is going to be integrated to?