Screen sharing in wlroots compositors

This is a guide on how to achieve screen sharing under any wlroots based compositor that runs on FreeBSD.

This does not apply to other wayland client implementations.

To get the portals working, we need to have dbus enabled. First of all, install dbus from either ports or binary repositories:

# pkg install dbus

Enable the service and start it

# service dbus enable
# service dbus start

Verify it is running correctly:

dbus-monitor

signal time=1644778417.267818 sender=org.freedesktop.DBus -> destination=:1.230 serial=2 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=NameAcquired
   string ":1.230"
signal time=1644778417.267897 sender=org.freedesktop.DBus -> destination=:1.230 serial=4 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=NameLost
   string ":1.230"

It's required to launch the respective compositor using a dbus session.

If it is started with an alias/command, it's enough to prepend

dbus-launch

to the exec command, like so:

dbus-launch wayfire

Otherwise, in case it is started via a Display Manager like ly or gdm, it's enough to edit the respective compositor's .desktop file under /usr/local/share/wayland-sessions/ :

vi /usr/local/share/wayland-sessions/wayfire.desktop

[Desktop Entry]
Name=Wayfire
Exec=dbus-launch wayfire
TryExec=wayfire
Icon=
Type=Application
DesktopNames=Wayfire

Installing pipewire is mandatory:

pkg install multimedia/pipewire

We require two xdg desktop portals, deskutils/xdg-desktop-portal and x11/xdg-desktop-portal-wlr.

xdg-desktop-portal is not available via the binary repositories at the time of this writing, so it is required to build it from the ports system.

# cd /usr/ports/multimedia/xdg-desktop-portal
# make install

Also as of the time of this writing, this port is marked as broken due to an unmatched feature in open(2). However, such feature is present in 13 STABLE.

xdg-desktop-portal-wlr is easily installable with pkg:

# pkg install xdg-desktop-portal-wlr

The following env vars ought to be present and correctly defined in order for screen sharing to work:

We need three processes running:

1.

pipewire -v

2.

/usr/local/libexec/xdg-desktop-portal -v -r

3.

/usr/local/libexec/xdg-desktop-portal-wlr -l DEBUG

It is possible to test if screen sharing is working under firefox by visiting the gUM test page; gUM Test Page.