This drops one dependency that we're not fully using anyway. Except for
the per-attribute validators that can be done in __post_init() we're not
using attrs for anything that dataclasses cannot do.
This is a bit convoluted because ei-scanner is named like that, so it
cannot be imported as python module. The solution for that is to
copy/rename it with meson to the builddir and run pytest in that. This
also allows us to set the path to the protocol XML file while we're at
it so we can use it as a fixture.
Actual tests are minimal for now, can be extended over time.
This protocol is wayland-like though it uses a slightly different
message format. The XML file uses the same structure, except for the
"fixed" type which is "float" here.
The scanner uses a jinja template to generate source and header files
for ei and eis which are now used instead of the protobuf-generated
objects. Note that the scanner is a minimal working version, some
features like enum value checks are not yet implemented.
Unlike wayland we do not need to generate the libwayland-like library,
we only need the wire protocol parser - some shortcuts can thus be taken.
To keep the changes simple, the protocol currently is a flat protocol
with only one interface and all messages copied over from the previous
ei.proto file. In future commits, this will be moved to the respective
interfaces instead.
Plain-text was useful for the initial implementation where the counterpart was
netcat but now that both parts are in place, protobuf is a much more
convenient system to handle a frequently-changing protocol.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
