You are talking about dbc files, defining the binary layout per message on the bus? That is typically in the hands of the OEMs, not ECU vendors.

See for example https://github.com/commaai/opendbc

Quite old and for Wundows, but a lot of code showing how to use a lot of CAN interface boxes is at https://github.com/rbei-etas/busmaster/tree/master/Sources/B...