Since commit 5567aefb, fixed modes haven't been automatically generated
for custom modes, so the output management implementation needs to be
able to handle them directly. To avoid polluting the mode list, only a
single custom mode can be listed at a time and will be removed when a
fixed mode is set.
Closes: https://gitlab.freedesktop.org/wlroots/wlroots/-/issues/3744
This allows the make/model/serial to be NULL when unset, and allows
them to be longer than the hardcoded array length.
This is a breaking change: compositors need to handle the new NULL
case, and we stop setting make/model to useless "headless" or
"wayland" strings.
The DRM backend adds custom modes to wlr_output.modes
Currently modes that are added after the first occurence of
wlr_output_configuration_head_v1 are not added to wlr_output_head.mode_resources.
The data of a head is only sent when it is enabled. While the head was disabled
data might have been changed. In this case clients were not informed about this
change. A later enable change that does not also update the other data must
still lead to the propagation of this data.
Since we do not know what other data was changed while the head was disabled
just send together with an enable change all current data.
Previously, if the current configuration contains an output X which is
destroyed, its head is automatically removed. If the compositor submits
the new configuration after X was removed, the current output
configuration is incorrectly detected to be the same as the previous
one, and no done event is sent. To prevent this, we can just keep track
of whether the current configuration is dirty, i.e whether we have sent
a done event for it.