Try looking at equivalent drivers under Linux, where source may be better tested and have better coverage. This might also allow you to reflect on the complexity, and your ability to port, and the value of such code.
I suspect most of the printers you're apt to find are "Image Printers" which require significant host side resources to render data sent to the print head. So large image buffers, font tables, graphic primitives, etc.
Perhaps look for a "Character Printer", or something that can accept PCL or PostScript, or acts a dongle
https://developers.hp.com/hp-printer-command-languages-pcl
