Wayland: Difference between revisions

From Alpine Linux
m (Simplify XDG_RUNTIME_DIR code)
(→‎XDG_RUNTIME_DIR: normalise titles)
 
(10 intermediate revisions by 4 users not shown)
Line 1: Line 1:
[https://en.wikipedia.org/wiki/Wayland%20(protocol) Wayland] is a new display protocol that aims to replace X11.
[https://en.wikipedia.org/wiki/Wayland%20(protocol) Wayland] is a new display protocol that aims to replace [[Xorg|X11]]. Wayland requires a [[Seat manager|seat manager]] to work. 


Multiple compositor implementations exist, including [[Sway]], [https://en.wikipedia.org/wiki/Mutter%20(software) Mutter] ([[GNOME]]'s compositor) and [https://en.wikipedia.org/wiki/KWin Kwin] ([http://KDE KDE]'s compositor). [https://wiki.archlinux.org/title/Wayland#Compositors A more exhaustive list is available in the ArchWiki].
The {{ic|setup-wayland-base}} script installs and enables [[elogind]] as [[Seat manager|seat manager]] besides enabling [[Repositories#Community|community repository]] and [[eudev]].
 
== Compositors ==
 
Display servers that implement the Wayland display server protocol are also called Wayland compositors because they additionally perform the task of a compositing window manager.
 
Multiple compositor implementations exist, including [[Sway]], [https://en.wikipedia.org/wiki/Mutter%20(software) Mutter] ([[GNOME]]'s compositor) and [https://en.wikipedia.org/wiki/KWin Kwin] ([[KDE]]'s compositor). The following [[:Category:Compositor|compositors]] are available in Alpine Linux.  


== XDG_RUNTIME_DIR ==
== XDG_RUNTIME_DIR ==


As per the protocol spec, Wayland compositors require the <code>XDG_RUNTIME_DIR</code> variable to be set. There are a few ways to configure create a temporary runtime directory and export this variable:
As per the protocol spec, Wayland compositors require the <code>XDG_RUNTIME_DIR</code> variable to be set.  
 
=== With elogind ===
 
When using [[elogind]] as a seat manager, it exports <code>XDG_RUNTIME_DIR</code> and other XDG environment variables automatically for each session. No further configuration is required.
 
=== With pam_rundir ===
 
[https://github.com/jjk-jacky/pam_rundir pam_rundir] is a [[PAM]] module that provides the runtime directory variable. Installing the package {{pkg|pam-rundir}} takes care of dependencies and no further configuration is required.
 
{{Note| <code>XDG_RUNTIME_DIR</code> variable MUST be initialised before the Wayland compositor, and also before the D-Bus session instance is started in your startup script/file for both the methods listed below.}}
 
=== With mkrundir ===


* [[elogind]] can do this and also export other XDG environment variables automatically for each session.
[https://git.sr.ht/~whynothugo/mkrundir mkrundir] is an executable that can be used to initialise the runtime directory explicitly by each user. To use <code>mkrundir</Code>, install the package {{pkg|mkrundir}} available in [[Repositories#Testing|testing]] repository. In your shell init script (e.g.: {{Path|~/.profile}} include an entry as follows at the '''top''' of the file {{Cat|~.profile|...
* {{pkg|pam-rundir}} can handle this for logins. To use this [[PAM]] is required.
export XDG_RUNTIME_DIR{{=}}$(mkrundir)
* Setting it up manually ([[#Configuring_XDG_RUNTIME_DIR_manually|see below]]).
...}}


Note that this variable MUST be initialised before the Wayland compositor, and also before the D-Bus session instance is started.
As per [https://git.sr.ht/~whynothugo/mkrundir mkrundir] website, this might have issues inside containers, due to privilege escalation.


=== Configuring XDG_RUNTIME_DIR manually ===
=== Creating and exporting XDG_RUNTIME_DIR manually ===


Generally, care should be taken when configuring the <code>XDG_*</code> variables manually as this configuration may have errors or conflict with other utilities that do this automatically.
Generally, care should be taken when configuring the <code>XDG_*</code> variables manually as this configuration may have errors or conflict with other utilities that do this automatically. Use this only on a system that's not using [[elogind]] and other solutions outlined above cannot handle this.  


On a system that's not using elogind nor any pam module that handles this, the <code>XDG_RUNTIME_DIR</code> can be initialised manually. The easiest approach is by adding a snippet like this one to shell init scripts (e.g.: {{Path|~/.profile}}):
The <code>XDG_RUNTIME_DIR</code> can be initialised manually by adding below snippet to shell init scripts (e.g.: {{Path|~/.profile}}):


{{Cat|~/.profile|<nowiki>if [ -z "$XDG_RUNTIME_DIR" ]; then
{{Cat|~/.profile|<nowiki>if [ -z "$XDG_RUNTIME_DIR" ]; then
XDG_RUNTIME_DIR="/tmp/$(id -u)"
XDG_RUNTIME_DIR="/tmp/$(id -u)-runtime-dir"


mkdir -pm 0700 "$XDG_RUNTIME_DIR"
mkdir -pm 0700 "$XDG_RUNTIME_DIR"
Line 35: Line 53:
[[Category:Desktop]]
[[Category:Desktop]]
[[Category:Wayland]]
[[Category:Wayland]]
[[Category:Compositor]]

Latest revision as of 20:57, 4 June 2025

Wayland is a new display protocol that aims to replace X11. Wayland requires a seat manager to work.

The setup-wayland-base script installs and enables elogind as seat manager besides enabling community repository and eudev.

Compositors

Display servers that implement the Wayland display server protocol are also called Wayland compositors because they additionally perform the task of a compositing window manager.

Multiple compositor implementations exist, including Sway, Mutter (GNOME's compositor) and Kwin (KDE's compositor). The following compositors are available in Alpine Linux.

XDG_RUNTIME_DIR

As per the protocol spec, Wayland compositors require the XDG_RUNTIME_DIR variable to be set.

With elogind

When using elogind as a seat manager, it exports XDG_RUNTIME_DIR and other XDG environment variables automatically for each session. No further configuration is required.

With pam_rundir

pam_rundir is a PAM module that provides the runtime directory variable. Installing the package pam-rundir takes care of dependencies and no further configuration is required.

Note: XDG_RUNTIME_DIR variable MUST be initialised before the Wayland compositor, and also before the D-Bus session instance is started in your startup script/file for both the methods listed below.

With mkrundir

mkrundir is an executable that can be used to initialise the runtime directory explicitly by each user. To use mkrundir, install the package mkrundir available in testing repository. In your shell init script (e.g.: ~/.profile include an entry as follows at the top of the file

Contents of ~.profile

... export XDG_RUNTIME_DIR=$(mkrundir) ...

As per mkrundir website, this might have issues inside containers, due to privilege escalation.

Creating and exporting XDG_RUNTIME_DIR manually

Generally, care should be taken when configuring the XDG_* variables manually as this configuration may have errors or conflict with other utilities that do this automatically. Use this only on a system that's not using elogind and other solutions outlined above cannot handle this.

The XDG_RUNTIME_DIR can be initialised manually by adding below snippet to shell init scripts (e.g.: ~/.profile):

Contents of ~/.profile

if [ -z "$XDG_RUNTIME_DIR" ]; then XDG_RUNTIME_DIR="/tmp/$(id -u)-runtime-dir" mkdir -pm 0700 "$XDG_RUNTIME_DIR" export XDG_RUNTIME_DIR fi

See also