[bug#50563] [PATCH [0/2] gnu: GDM: Add Wayland support

[bug#50563] [PATCH [0/2] gnu: GDM: Add Wayland support

[Josselin Poiret]

Hi,

This patchset enables Wayland support for GDM: launching GDM itself on Wayland and launching Wayland sessions (the former requires the latter).
This is my first contribution, so do not hesitate to give any feedback (I also haven't setup `git send-email` yet so this is a manual mail).

1. Enables optional support for launching a Wayland GDM session.
2. Adds a wrapper for Wayland sessions in order to setup the environment, similar to the default `/etc/profile` or `xinitrc`.

Best,
Josselin Poiret

[bug#50563] [PATCH 1/2] gnu: Add Wayland support for GDM

[Josselin Poiret via Guix-patches via]

* Add the optional flag `wayland?` in `gdm-configuration` to launch GDM with
Wayland, enabling the use of Wayland sessions with GDM.

* Remove hardcoded Xwayland check in GDM.
* Add `XCURSOR_PATH` to GDM environment.
* Update the documentation.
---
 doc/guix.texi                                 | 33 ++++++++++++-------
 gnu/packages/gnome.scm                        |  3 +-
 .../gdm-remove-hardcoded-xwayland-path.patch  | 22 +++++++++++++
 gnu/services/xorg.scm                         | 14 +++++---
 4 files changed, 56 insertions(+), 16 deletions(-)
 create mode 100644 gnu/packages/patches/gdm-remove-hardcoded-xwayland-path.patch

diff --git a/doc/guix.texi b/doc/guix.texi
index 220499503d..93ea4a321f 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -18043,19 +18043,26 @@ example the @code{windowmaker} or @code{openbox} packages---preferably
 by adding it to the @code{packages} field of your operating system
 definition (@pxref{operating-system Reference, system-wide packages}).

+@anchor{wayland-gdm}
+GDM also supports Wayland: it can itself use Wayland instead of X11 for
+its user interface, and it can also start Wayland sessions.  The former is
+required for the latter, to enable, set @code{wayland?} to @code{#t} in
+@code{gdm-configuration}.
+
 @defvr {Scheme Variable} gdm-service-type
 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
 Desktop Manager} (GDM), a program that manages graphical display servers and
 handles graphical user logins.  Its value must be a @code{gdm-configuration}
 (see below).

-@cindex session types (X11)
-@cindex X11 session types
+@cindex session types
 GDM looks for @dfn{session types} described by the @file{.desktop} files in
-@file{/run/current-system/profile/share/xsessions} and allows users to choose
-a session from the log-in screen.  Packages such as @code{gnome}, @code{xfce},
-and @code{i3} provide @file{.desktop} files; adding them to the system-wide
-set of packages automatically makes them available at the log-in screen.
+@file{/run/current-system/profile/share/xsessions} (for X11 sessions) and
+@file{/run/current-system/profile/share/wayland-sessions} (for Wayland
+sessions) and allows users to choose a session from the log-in screen.
+Packages such as @code{gnome}, @code{xfce}, @code{i3} and @code{sway} provide
+@file{.desktop} files; adding them to the system-wide set of packages
+automatically makes them available at the log-in screen.

 In addition, @file{~/.xsession} files are honored.  When available,
 @file{~/.xsession} must be an executable that starts a window manager
@@ -18088,6 +18095,9 @@ File name of the @code{dbus-daemon} executable.

 @item @code{gdm} (default: @code{gdm})
 The GDM package to use.
+
+@item @code{wayland?} (default: @code{#f})
+When true, enables Wayland in GDM, necessary to use Wayland sessions.
 @end table
 @end deftp

@@ -19310,11 +19320,12 @@ expected.

 The desktop environments in Guix use the Xorg display server by
 default.  If you'd like to use the newer display server protocol
-called Wayland, you need to use the @code{sddm-service} instead of
-GDM as the graphical login manager.  You should then
-select the ``GNOME (Wayland)'' session in SDDM@.  Alternatively you can
-also try starting GNOME on Wayland manually from a TTY with the
-command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
+called Wayland, you need to enable Wayland support in GDM
+(@pxref{wayland-gdm}).  Another solution is to use the
+@code{sddm-service} instead of GDM as the graphical login manager.
+You should then select the ``GNOME (Wayland)'' session in SDDM@.
+Alternatively you can also try starting GNOME on Wayland manually from a
+TTY with the command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
 gnome-session``.  Currently only GNOME has support for Wayland.

 @defvr {Scheme Variable} gnome-desktop-service-type
diff --git a/gnu/packages/gnome.scm b/gnu/packages/gnome.scm
index 5a8bcdb8ce..2da0b3791f 100644
--- a/gnu/packages/gnome.scm
+++ b/gnu/packages/gnome.scm
@@ -8111,7 +8111,8 @@ library.")
               (sha256
                (base32
                 "1lyqvcwxhwxklbxn4xjswjzr6fhjix6h28mi9ypn34wdm9bzcpg8"))
-              (patches (search-patches "gdm-default-session.patch"))))
+              (patches (search-patches "gdm-default-session.patch"
+                                       "gdm-remove-hardcoded-xwayland-path.patch"))))
     (build-system glib-or-gtk-build-system)
     (arguments
      '(#:configure-flags
diff --git a/gnu/packages/patches/gdm-remove-hardcoded-xwayland-path.patch b/gnu/packages/patches/gdm-remove-hardcoded-xwayland-path.patch
new file mode 100644
index 0000000000..321a0e4b87
--- /dev/null
+++ b/gnu/packages/patches/gdm-remove-hardcoded-xwayland-path.patch
@@ -0,0 +1,22 @@
+Remove check for hardcoded Xwayland path in gdm.
+
+---
+ daemon/gdm-local-display-factory.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/daemon/gdm-local-display-factory.c b/daemon/gdm-local-display-factory.c
+index da1093bb..37355c06 100644
+--- a/daemon/gdm-local-display-factory.c
++++ b/daemon/gdm-local-display-factory.c
+@@ -203,7 +203,7 @@ gdm_local_display_factory_use_wayland (void)
+ #ifdef ENABLE_WAYLAND_SUPPORT
+         gboolean wayland_enabled = FALSE;
+         if (gdm_settings_direct_get_boolean (GDM_KEY_WAYLAND_ENABLE, &wayland_enabled)) {
+-                if (wayland_enabled && g_file_test ("/usr/bin/Xwayland", G_FILE_TEST_IS_EXECUTABLE) )
++                if (wayland_enabled)
+                         return TRUE;
+         }
+ #endif
+--
+2.33.0
+
diff --git a/gnu/services/xorg.scm b/gnu/services/xorg.scm
index d5c5316d3f..fe25168a58 100644
--- a/gnu/services/xorg.scm
+++ b/gnu/services/xorg.scm
@@ -883,7 +883,8 @@ the GNOME desktop environment.")
   (xorg-configuration gdm-configuration-xorg
                       (default (xorg-configuration)))
   (x-session gdm-configuration-x-session
-             (default (xinitrc))))
+             (default (xinitrc)))
+  (wayland? gdm-configuration-wayland? (default #f)))

 (define (gdm-configuration-file config)
   (mixed-text-file "gdm-custom.conf"
@@ -909,8 +910,9 @@ the GNOME desktop environment.")
                    ;; See also
                    ;; <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=39281>.
                    "InitialSetupEnable=false\n"
-                   ;; Enable me once X is working.
-                   "WaylandEnable=false\n"
+                   "WaylandEnable=" (if (gdm-configuration-wayland? config)
+                                        "true"
+                                        "false") "\n"
                    "\n"
                    "[debug]\n"
                    "Enable=" (if (gdm-configuration-debug? config)
@@ -976,7 +978,11 @@ the GNOME desktop environment.")
                                   ;; can depend on GNOME Shell directly.
                                   (cons #$gnome-shell
                                         '#$(gdm-configuration-gnome-shell-assets
-                                            config)))))))))
+                                            config)))))
+                           ;; Add XCURSOR_PATH so that mutter can find its cursors.
+                           ;; gdm doesn't login so doesn't source the corresponding
+                           ;; line in /etc/profile
+                           "XCURSOR_PATH=/run/current-system/profile/share/icons"))))
          (stop #~(make-kill-destructor))
          (respawn? #t))))

--
2.33.0

[bug#50563] [PATCH 2/2] gnu: gdm: Add Wayland session wrapper script.

[Josselin Poiret via Guix-patches via]

* Patch GDM to support launching a wrapper script for Wayland sessions.
* Add `wayland-session` in `gdm-configuration` to specify the wrapper to use.
* Add default wrapper that runs non-GDM sessions through a login shell (based
on the `xinitrc`).
* Update the documentation with those changes.
---
 doc/guix.texi                                 |  4 +++
 gnu/packages/gnome.scm                        |  3 +-
 ...gdm-wayland-session-wrapper-from-env.patch | 35 +++++++++++++++++++
 gnu/services/xorg.scm                         | 21 +++++++++--
 4 files changed, 60 insertions(+), 3 deletions(-)
 create mode 100644 gnu/packages/patches/gdm-wayland-session-wrapper-from-env.patch

diff --git a/doc/guix.texi b/doc/guix.texi
index 93ea4a321f..3e6157c8ab 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -18098,6 +18098,10 @@ The GDM package to use.

 @item @code{wayland?} (default: @code{#f})
 When true, enables Wayland in GDM, necessary to use Wayland sessions.
+
+@item @code{wayland-session} (default: @code{gdm-wayland-session-wrapper})
+The Wayland session wrapper to use, needed to setup the
+environment.
 @end table
 @end deftp

diff --git a/gnu/packages/gnome.scm b/gnu/packages/gnome.scm
index 2da0b3791f..36d58e4c42 100644
--- a/gnu/packages/gnome.scm
+++ b/gnu/packages/gnome.scm
@@ -8112,7 +8112,8 @@ library.")
                (base32
                 "1lyqvcwxhwxklbxn4xjswjzr6fhjix6h28mi9ypn34wdm9bzcpg8"))
               (patches (search-patches "gdm-default-session.patch"
-                                       "gdm-remove-hardcoded-xwayland-path.patch"))))
+                                       "gdm-remove-hardcoded-xwayland-path.patch"
+                                       "gdm-wayland-session-wrapper-from-env.patch"))))
     (build-system glib-or-gtk-build-system)
     (arguments
      '(#:configure-flags
diff --git a/gnu/packages/patches/gdm-wayland-session-wrapper-from-env.patch b/gnu/packages/patches/gdm-wayland-session-wrapper-from-env.patch
new file mode 100644
index 0000000000..ca1af557ef
--- /dev/null
+++ b/gnu/packages/patches/gdm-wayland-session-wrapper-from-env.patch
@@ -0,0 +1,35 @@
+Get wayland-session wrapper from environment
+
+---
+ daemon/gdm-session.c | 6 ++++--
+ 1 file changed, 4 insertions(+), 2 deletions(-)
+
+diff --git a/daemon/gdm-session.c b/daemon/gdm-session.c
+index 4e303e70..1deca4e9 100644
+--- a/daemon/gdm-session.c
++++ b/daemon/gdm-session.c
+@@ -2888,8 +2888,9 @@ gdm_session_start_session (GdmSession *self,
+                                                            allow_remote_connections? "--allow-remote-connections " : "",
+                                                            command);
+                         } else {
+-                                program = g_strdup_printf (LIBEXECDIR "/gdm-wayland-session %s\"%s\"",
++                                program = g_strdup_printf (LIBEXECDIR "/gdm-wayland-session %s\"%s %s\"",
+                                                            register_session ? "--register-session " : "",
++                                                           g_getenv ("GDM_WAYLAND_SESSION"),
+                                                            command);
+                         }
+                 } else if (run_xsession_script) {
+@@ -2906,8 +2907,9 @@ gdm_session_start_session (GdmSession *self,
+                                                            register_session ? "--register-session " : "",
+                                                            self->selected_program);
+                         } else {
+-                                program = g_strdup_printf (LIBEXECDIR "/gdm-wayland-session %s\"%s\"",
++                                program = g_strdup_printf (LIBEXECDIR "/gdm-wayland-session %s\"%s %s\"",
+                                                            register_session ? "--register-session " : "",
++                                                           g_getenv ("GDM_WAYLAND_SESSION"),
+                                                            self->selected_program);
+                         }
+                 } else {
+--
+2.33.0
+
diff --git a/gnu/services/xorg.scm b/gnu/services/xorg.scm
index fe25168a58..a9b2a1a1c6 100644
--- a/gnu/services/xorg.scm
+++ b/gnu/services/xorg.scm
@@ -869,6 +869,19 @@ the GNOME desktop environment.")
        (apply execl (string-append #$dbus "/bin/dbus-daemon")
               (program-arguments)))))

+;; Wrapper script for Wayland sessions, similar to Xsession.
+;; Used to setup the environment.
+(define gdm-wayland-session-wrapper
+  (program-file
+   "gdm-wayland-session-wrapper"
+   #~((let* ((user (getpw (getuid)))
+	    (name (passwd:name user))
+	    (shell (passwd:shell user))
+	    (args (cdr (command-line))))
+        (if (string=? name "gdm")
+	    (apply execl (cons (car args) args))
+	    (execl shell shell "--login" "-c" (string-join args)))))))
+
 (define-record-type* <gdm-configuration>
   gdm-configuration make-gdm-configuration
   gdm-configuration?
@@ -884,7 +897,8 @@ the GNOME desktop environment.")
                       (default (xorg-configuration)))
   (x-session gdm-configuration-x-session
              (default (xinitrc)))
-  (wayland? gdm-configuration-wayland? (default #f)))
+  (wayland? gdm-configuration-wayland? (default #f))
+  (wayland-session gdm-configuration-wayland-session (default gdm-wayland-session-wrapper)))

 (define (gdm-configuration-file config)
   (mixed-text-file "gdm-custom.conf"
@@ -982,7 +996,10 @@ the GNOME desktop environment.")
                            ;; Add XCURSOR_PATH so that mutter can find its cursors.
                            ;; gdm doesn't login so doesn't source the corresponding
                            ;; line in /etc/profile
-                           "XCURSOR_PATH=/run/current-system/profile/share/icons"))))
+                           "XCURSOR_PATH=/run/current-system/profile/share/icons"
+                           (string-append
+                            "GDM_WAYLAND_SESSION="
+                            #$(gdm-configuration-wayland-session config))))))
          (stop #~(make-kill-destructor))
          (respawn? #t))))

--
2.33.0

[bug#50563] [PATCH 1/2] gnu: Add Wayland support for GDM

[Josselin Poiret]

* Add the optional flag `wayland?` in `gdm-configuration` to launch GDM with
Wayland, enabling the use of Wayland sessions with GDM.

* Remove hardcoded Xwayland check in GDM.
* Add `XCURSOR_PATH` to GDM environment.
* Update the documentation.
---
 doc/guix.texi                                 | 33 ++++++++++++-------
 gnu/packages/gnome.scm                        |  3 +-
 .../gdm-remove-hardcoded-xwayland-path.patch  | 22 +++++++++++++
 gnu/services/xorg.scm                         | 14 +++++---
 4 files changed, 56 insertions(+), 16 deletions(-)
 create mode 100644 gnu/packages/patches/gdm-remove-hardcoded-xwayland-path.patch

diff --git a/doc/guix.texi b/doc/guix.texi
index 220499503d..93ea4a321f 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -18043,19 +18043,26 @@ example the @code{windowmaker} or @code{openbox} packages---preferably
 by adding it to the @code{packages} field of your operating system
 definition (@pxref{operating-system Reference, system-wide packages}).

+@anchor{wayland-gdm}
+GDM also supports Wayland: it can itself use Wayland instead of X11 for
+its user interface, and it can also start Wayland sessions.  The former is
+required for the latter, to enable, set @code{wayland?} to @code{#t} in
+@code{gdm-configuration}.
+
 @defvr {Scheme Variable} gdm-service-type
 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
 Desktop Manager} (GDM), a program that manages graphical display servers and
 handles graphical user logins.  Its value must be a @code{gdm-configuration}
 (see below).

-@cindex session types (X11)
-@cindex X11 session types
+@cindex session types
 GDM looks for @dfn{session types} described by the @file{.desktop} files in
-@file{/run/current-system/profile/share/xsessions} and allows users to choose
-a session from the log-in screen.  Packages such as @code{gnome}, @code{xfce},
-and @code{i3} provide @file{.desktop} files; adding them to the system-wide
-set of packages automatically makes them available at the log-in screen.
+@file{/run/current-system/profile/share/xsessions} (for X11 sessions) and
+@file{/run/current-system/profile/share/wayland-sessions} (for Wayland
+sessions) and allows users to choose a session from the log-in screen.
+Packages such as @code{gnome}, @code{xfce}, @code{i3} and @code{sway} provide
+@file{.desktop} files; adding them to the system-wide set of packages
+automatically makes them available at the log-in screen.

 In addition, @file{~/.xsession} files are honored.  When available,
 @file{~/.xsession} must be an executable that starts a window manager
@@ -18088,6 +18095,9 @@ File name of the @code{dbus-daemon} executable.

 @item @code{gdm} (default: @code{gdm})
 The GDM package to use.
+
+@item @code{wayland?} (default: @code{#f})
+When true, enables Wayland in GDM, necessary to use Wayland sessions.
 @end table
 @end deftp

@@ -19310,11 +19320,12 @@ expected.

 The desktop environments in Guix use the Xorg display server by
 default.  If you'd like to use the newer display server protocol
-called Wayland, you need to use the @code{sddm-service} instead of
-GDM as the graphical login manager.  You should then
-select the ``GNOME (Wayland)'' session in SDDM@.  Alternatively you can
-also try starting GNOME on Wayland manually from a TTY with the
-command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
+called Wayland, you need to enable Wayland support in GDM
+(@pxref{wayland-gdm}).  Another solution is to use the
+@code{sddm-service} instead of GDM as the graphical login manager.
+You should then select the ``GNOME (Wayland)'' session in SDDM@.
+Alternatively you can also try starting GNOME on Wayland manually from a
+TTY with the command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
 gnome-session``.  Currently only GNOME has support for Wayland.

 @defvr {Scheme Variable} gnome-desktop-service-type
diff --git a/gnu/packages/gnome.scm b/gnu/packages/gnome.scm
index 5a8bcdb8ce..2da0b3791f 100644
--- a/gnu/packages/gnome.scm
+++ b/gnu/packages/gnome.scm
@@ -8111,7 +8111,8 @@ library.")
               (sha256
                (base32
                 "1lyqvcwxhwxklbxn4xjswjzr6fhjix6h28mi9ypn34wdm9bzcpg8"))
-              (patches (search-patches "gdm-default-session.patch"))))
+              (patches (search-patches "gdm-default-session.patch"
+                                       "gdm-remove-hardcoded-xwayland-path.patch"))))
     (build-system glib-or-gtk-build-system)
     (arguments
      '(#:configure-flags
diff --git a/gnu/packages/patches/gdm-remove-hardcoded-xwayland-path.patch b/gnu/packages/patches/gdm-remove-hardcoded-xwayland-path.patch
new file mode 100644
index 0000000000..321a0e4b87
--- /dev/null
+++ b/gnu/packages/patches/gdm-remove-hardcoded-xwayland-path.patch
@@ -0,0 +1,22 @@
+Remove check for hardcoded Xwayland path in gdm.
+
+---
+ daemon/gdm-local-display-factory.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/daemon/gdm-local-display-factory.c b/daemon/gdm-local-display-factory.c
+index da1093bb..37355c06 100644
+--- a/daemon/gdm-local-display-factory.c
++++ b/daemon/gdm-local-display-factory.c
+@@ -203,7 +203,7 @@ gdm_local_display_factory_use_wayland (void)
+ #ifdef ENABLE_WAYLAND_SUPPORT
+         gboolean wayland_enabled = FALSE;
+         if (gdm_settings_direct_get_boolean (GDM_KEY_WAYLAND_ENABLE, &wayland_enabled)) {
+-                if (wayland_enabled && g_file_test ("/usr/bin/Xwayland", G_FILE_TEST_IS_EXECUTABLE) )
++                if (wayland_enabled)
+                         return TRUE;
+         }
+ #endif
+--
+2.33.0
+
diff --git a/gnu/services/xorg.scm b/gnu/services/xorg.scm
index d5c5316d3f..fe25168a58 100644
--- a/gnu/services/xorg.scm
+++ b/gnu/services/xorg.scm
@@ -883,7 +883,8 @@ the GNOME desktop environment.")
   (xorg-configuration gdm-configuration-xorg
                       (default (xorg-configuration)))
   (x-session gdm-configuration-x-session
-             (default (xinitrc))))
+             (default (xinitrc)))
+  (wayland? gdm-configuration-wayland? (default #f)))

 (define (gdm-configuration-file config)
   (mixed-text-file "gdm-custom.conf"
@@ -909,8 +910,9 @@ the GNOME desktop environment.")
                    ;; See also
                    ;; <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=39281>.
                    "InitialSetupEnable=false\n"
-                   ;; Enable me once X is working.
-                   "WaylandEnable=false\n"
+                   "WaylandEnable=" (if (gdm-configuration-wayland? config)
+                                        "true"
+                                        "false") "\n"
                    "\n"
                    "[debug]\n"
                    "Enable=" (if (gdm-configuration-debug? config)
@@ -976,7 +978,11 @@ the GNOME desktop environment.")
                                   ;; can depend on GNOME Shell directly.
                                   (cons #$gnome-shell
                                         '#$(gdm-configuration-gnome-shell-assets
-                                            config)))))))))
+                                            config)))))
+                           ;; Add XCURSOR_PATH so that mutter can find its cursors.
+                           ;; gdm doesn't login so doesn't source the corresponding
+                           ;; line in /etc/profile
+                           "XCURSOR_PATH=/run/current-system/profile/share/icons"))))
          (stop #~(make-kill-destructor))
          (respawn? #t))))

--
2.33.0

[bug#50563] [PATCH 2/2] gnu: gdm: Add Wayland session wrapper script.

[Josselin Poiret]

* Patch GDM to support launching a wrapper script for Wayland sessions.
* Add `wayland-session` in `gdm-configuration` to specify the wrapper to use.
* Add default wrapper that runs non-GDM sessions through a login shell (based
on the `xinitrc`).
* Update the documentation with those changes.
---
 doc/guix.texi                                 |  4 +++
 gnu/packages/gnome.scm                        |  3 +-
 ...gdm-wayland-session-wrapper-from-env.patch | 35 +++++++++++++++++++
 gnu/services/xorg.scm                         | 21 +++++++++--
 4 files changed, 60 insertions(+), 3 deletions(-)
 create mode 100644 gnu/packages/patches/gdm-wayland-session-wrapper-from-env.patch

diff --git a/doc/guix.texi b/doc/guix.texi
index 93ea4a321f..3e6157c8ab 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -18098,6 +18098,10 @@ The GDM package to use.

 @item @code{wayland?} (default: @code{#f})
 When true, enables Wayland in GDM, necessary to use Wayland sessions.
+
+@item @code{wayland-session} (default: @code{gdm-wayland-session-wrapper})
+The Wayland session wrapper to use, needed to setup the
+environment.
 @end table
 @end deftp

diff --git a/gnu/packages/gnome.scm b/gnu/packages/gnome.scm
index 2da0b3791f..36d58e4c42 100644
--- a/gnu/packages/gnome.scm
+++ b/gnu/packages/gnome.scm
@@ -8112,7 +8112,8 @@ library.")
                (base32
                 "1lyqvcwxhwxklbxn4xjswjzr6fhjix6h28mi9ypn34wdm9bzcpg8"))
               (patches (search-patches "gdm-default-session.patch"
-                                       "gdm-remove-hardcoded-xwayland-path.patch"))))
+                                       "gdm-remove-hardcoded-xwayland-path.patch"
+                                       "gdm-wayland-session-wrapper-from-env.patch"))))
     (build-system glib-or-gtk-build-system)
     (arguments
      '(#:configure-flags
diff --git a/gnu/packages/patches/gdm-wayland-session-wrapper-from-env.patch b/gnu/packages/patches/gdm-wayland-session-wrapper-from-env.patch
new file mode 100644
index 0000000000..ca1af557ef
--- /dev/null
+++ b/gnu/packages/patches/gdm-wayland-session-wrapper-from-env.patch
@@ -0,0 +1,35 @@
+Get wayland-session wrapper from environment
+
+---
+ daemon/gdm-session.c | 6 ++++--
+ 1 file changed, 4 insertions(+), 2 deletions(-)
+
+diff --git a/daemon/gdm-session.c b/daemon/gdm-session.c
+index 4e303e70..1deca4e9 100644
+--- a/daemon/gdm-session.c
++++ b/daemon/gdm-session.c
+@@ -2888,8 +2888,9 @@ gdm_session_start_session (GdmSession *self,
+                                                            allow_remote_connections? "--allow-remote-connections " : "",
+                                                            command);
+                         } else {
+-                                program = g_strdup_printf (LIBEXECDIR "/gdm-wayland-session %s\"%s\"",
++                                program = g_strdup_printf (LIBEXECDIR "/gdm-wayland-session %s\"%s %s\"",
+                                                            register_session ? "--register-session " : "",
++                                                           g_getenv ("GDM_WAYLAND_SESSION"),
+                                                            command);
+                         }
+                 } else if (run_xsession_script) {
+@@ -2906,8 +2907,9 @@ gdm_session_start_session (GdmSession *self,
+                                                            register_session ? "--register-session " : "",
+                                                            self->selected_program);
+                         } else {
+-                                program = g_strdup_printf (LIBEXECDIR "/gdm-wayland-session %s\"%s\"",
++                                program = g_strdup_printf (LIBEXECDIR "/gdm-wayland-session %s\"%s %s\"",
+                                                            register_session ? "--register-session " : "",
++                                                           g_getenv ("GDM_WAYLAND_SESSION"),
+                                                            self->selected_program);
+                         }
+                 } else {
+--
+2.33.0
+
diff --git a/gnu/services/xorg.scm b/gnu/services/xorg.scm
index fe25168a58..a9b2a1a1c6 100644
--- a/gnu/services/xorg.scm
+++ b/gnu/services/xorg.scm
@@ -869,6 +869,19 @@ the GNOME desktop environment.")
        (apply execl (string-append #$dbus "/bin/dbus-daemon")
               (program-arguments)))))

+;; Wrapper script for Wayland sessions, similar to Xsession.
+;; Used to setup the environment.
+(define gdm-wayland-session-wrapper
+  (program-file
+   "gdm-wayland-session-wrapper"
+   #~((let* ((user (getpw (getuid)))
+	    (name (passwd:name user))
+	    (shell (passwd:shell user))
+	    (args (cdr (command-line))))
+        (if (string=? name "gdm")
+	    (apply execl (cons (car args) args))
+	    (execl shell shell "--login" "-c" (string-join args)))))))
+
 (define-record-type* <gdm-configuration>
   gdm-configuration make-gdm-configuration
   gdm-configuration?
@@ -884,7 +897,8 @@ the GNOME desktop environment.")
                       (default (xorg-configuration)))
   (x-session gdm-configuration-x-session
              (default (xinitrc)))
-  (wayland? gdm-configuration-wayland? (default #f)))
+  (wayland? gdm-configuration-wayland? (default #f))
+  (wayland-session gdm-configuration-wayland-session (default gdm-wayland-session-wrapper)))

 (define (gdm-configuration-file config)
   (mixed-text-file "gdm-custom.conf"
@@ -982,7 +996,10 @@ the GNOME desktop environment.")
                            ;; Add XCURSOR_PATH so that mutter can find its cursors.
                            ;; gdm doesn't login so doesn't source the corresponding
                            ;; line in /etc/profile
-                           "XCURSOR_PATH=/run/current-system/profile/share/icons"))))
+                           "XCURSOR_PATH=/run/current-system/profile/share/icons"
+                           (string-append
+                            "GDM_WAYLAND_SESSION="
+                            #$(gdm-configuration-wayland-session config))))))
          (stop #~(make-kill-destructor))
          (respawn? #t))))

--
2.33.0

[bug#50563] (No Subject)

[Josselin Poiret via Guix-patches via]

My bad, I've confused my email addresses, so both patches were sent twice. Please disregard the duplicated mails.

On another note, I've only been testing with `sway` and don't really have the disk space right now to test Wayland GNOME itself, but I think it should work fine. Maybe someone else can pitch in on this.

[bug#50563] [PATCH 2/2] gnu: gdm: Add Wayland session wrapper script.

[Maxime Devos]

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Josselin Poiret schreef op ma 13-09-2021 om 08:15 [+0000]:
> * Patch GDM to support launching a wrapper script for Wayland sessions.
> * Add `wayland-session` in `gdm-configuration` to specify the wrapper to use.
> * Add default wrapper that runs non-GDM sessions through a login shell (based
> on the `xinitrc`).
> * Update the documentation with those changes.
> ---
>  doc/guix.texi                                 |  4 +++
>  gnu/packages/gnome.scm                        |  3 +-
>  ...gdm-wayland-session-wrapper-from-env.patch | 35 +++++++++++++++++++
>  gnu/services/xorg.scm                         | 21 +++++++++--
>  4 files changed, 60 insertions(+), 3 deletions(-)
>  create mode 100644 gnu/packages/patches/gdm-wayland-session-wrapper-from-env.patch
> 
> diff --git a/doc/guix.texi b/doc/guix.texi
> index 93ea4a321f..3e6157c8ab 100644
> --- a/doc/guix.texi
> +++ b/doc/guix.texi
> @@ -18098,6 +18098,10 @@ The GDM package to use.
> 
>  @item @code{wayland?} (default: @code{#f})
>  When true, enables Wayland in GDM, necessary to use Wayland sessions.
> +
> +@item @code{wayland-session} (default: @code{gdm-wayland-session-wrapper})
> +The Wayland session wrapper to use, needed to setup the
> +environment.

‘needed to setup the environment’ --> this sounds like sometimes, the session
wrapper needs to be changed such that the environment variables are correct.
However, gdm-wayland-session-wrapper doesn't actually set any environment variables,
and the X equivalent 'xsession' doesn't need to be modified (at least on my system,
when I last used gdm), so I presume the default is quite reasonable for most users.

So to reduce confusion, I would drop the ‘needed to set up the environment’.

A ‘real-world’ example of a custom 'wayland-session' would be helpful to illustrate
matters.

Greetings,
Maxime

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[bug#50563] (No Subject)

[Jack Hill]

On Mon, 13 Sep 2021, Josselin Poiret via Guix-patches via wrote:

> On another note, I've only been testing with `sway` and don't really 
> have the disk space right now to test Wayland GNOME itself, but I think 
> it should work fine. Maybe someone else can pitch in on this.

I've tested launching a Wayland GNOME session on x86-64 and everything 
works as expected there. Thanks for the patches!

Best,
Jack

[bug#50563] Re: [bug#50563] [PATCH 2/2] gnu: gdm: Add Wayland session wrapper script.

[Josselin Poiret]

Maxime: I agree that this was a very confusing wording. Here is a reformulation that I hope clears up any misunderstanding.
PS: `gdm-wayland-session-wrapper` does in fact set environment variables, only that it indirectly uses `/etc/profile` to do so. Otherwise, the default profile wouldn't be active in the wayland session.

---
 doc/guix.texi | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/doc/guix.texi b/doc/guix.texi
index 3e6157c8ab..8a0eba16e1 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -18064,9 +18064,9 @@ Packages such as @code{gnome}, @code{xfce}, @code{i3} and @code{sway} provide
 @file{.desktop} files; adding them to the system-wide set of packages
 automatically makes them available at the log-in screen.

-In addition, @file{~/.xsession} files are honored.  When available,
-@file{~/.xsession} must be an executable that starts a window manager
-and/or other X clients.
+In addition, @file{~/.xsession} files are honored when launching X11 sessions.
+When available, @file{~/.xsession} must be an executable that starts a window
+manager and/or other X clients.
 @end defvr

 @deftp {Data Type} gdm-configuration
@@ -18100,8 +18100,8 @@ The GDM package to use.
 When true, enables Wayland in GDM, necessary to use Wayland sessions.

 @item @code{wayland-session} (default: @code{gdm-wayland-session-wrapper})
-The Wayland session wrapper to use, needed to setup the
-environment.
+The Wayland session wrapper to use, analogous to @code{xsession}. The default
+wrapper simply launches the session in a login shell.
 @end table
 @end deftp

--
2.33.0

Jack: Great news! I've been using it on my daily driver as well, without any problem so far.

[bug#50563] Re: [bug#50563] [PATCH 2/2] gnu: gdm: Add Wayland session wrapper script.

[Maxime Devos]

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Josselin Poiret schreef op di 14-09-2021 om 21:45 [+0000]:
> Maxime: I agree that this was a very confusing wording. Here is a reformulation that I hope clears up any misunderstanding.
> PS: `gdm-wayland-session-wrapper` does in fact set environment variables, only that it indirectly uses `/etc/profile` to do so. Otherwise, the default profile wouldn't be active in the wayland session.
> 
> [...]
> 
> -In addition, @file{~/.xsession} files are honored.  When available,
> -@file{~/.xsession} must be an executable that starts a window manager
> -and/or other X clients.
> +In addition, @file{~/.xsession} files are honored when launching X11 sessions.
> +When available, @file{~/.xsession} must be an executable that starts a window
> +manager and/or other X clients.
>  @end defvr
> 
>  @deftp {Data Type} gdm-configuration
> @@ -18100,8 +18100,8 @@ The GDM package to use.
>  When true, enables Wayland in GDM, necessary to use Wayland sessions.
> 
>  @item @code{wayland-session} (default: @code{gdm-wayland-session-wrapper})
> -The Wayland session wrapper to use, needed to setup the
> -environment.
> +The Wayland session wrapper to use, analogous to @code{xsession}. The default
> +wrapper simply launches the session in a login shell.
>  @end table
>  @end deftp

This is clear to me, thanks!

Greetings,
Maxime.

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[bug#50563] [PATCH [0/2] gnu: GDM: Add Wayland support

[Mathieu Othacehe]

Hello Josselin,

> This is my first contribution, so do not hesitate to give any feedback
> (I also haven't setup `git send-email` yet so this is a manual mail).

Thanks for this first contribution! I was able to apply the patches just
fine. However, it would nice if you could write commit messages
respecting the ChangeLog format as explained here:
https://guix.gnu.org/manual/en/html_node/Submitting-Patches.html.

> 1. Enables optional support for launching a Wayland GDM session.
> 2. Adds a wrapper for Wayland sessions in order to setup the
> environment, similar to the default `/etc/profile` or `xinitrc`.

I tried to apply both patches on top of the wip-gnome40 branch to see if
I can get Wayland support. There are minor merge conflicts that are
solved on the wip-gnome40-wayland branch.

I then edited the desktop.tmpl file this way:

--8<---------------cut here---------------start------------->8---
--- a/gnu/system/examples/desktop.tmpl
+++ b/gnu/system/examples/desktop.tmpl
@@ -64,12 +64,15 @@
   ;; by clicking the gear.  Use the "desktop" services, which
   ;; include the X11 log-in service, networking with
   ;; NetworkManager, and more.
-  (services (append (list (service gnome-desktop-service-type)
-                          (service xfce-desktop-service-type)
-                          (set-xorg-configuration
-                           (xorg-configuration
-                            (keyboard-layout keyboard-layout))))
-                    %desktop-services))
+  (services (modify-services
+                (append (list (service gnome-desktop-service-type)
+                              (set-xorg-configuration
+                               (xorg-configuration
+                                (keyboard-layout keyboard-layout))))
+                    %desktop-services)
+              (gdm-service-type config =>
+                                (gdm-configuration
+                                 (wayland? #t)))))
 
   ;; Allow resolution of '.local' host names with mDNS.
   (name-service-switch %mdns-host-lookup-nss))
--8<---------------cut here---------------end--------------->8---

And tested it by running:

--8<---------------cut here---------------start------------->8---
$(./pre-inst-env guix system vm gnu/system/examples/desktop.tmpl
--no-grafts --no-offload -v3 -K) -m 2048
--8<---------------cut here---------------end--------------->8---

Looks like there's a good old xorg-server running, plus the "About"
section in GNOME configuration reports that it is running using the X11
window system.

Anything wrong with my integration?

Thanks,

Mathieu

[bug#50563] [PATCH [0/2] gnu: GDM: Add Wayland support

[Mathieu Othacehe]

> Anything wrong with my integration?

I notied that mutter was complaining that the /tmp/.X11-unix file was
missing the sticky bit when launching the xorg-xwayland binary.

The following patch fixes it for me:

diff --git a/gnu/services/desktop.scm b/gnu/services/desktop.scm
index 64d0e85301..612d548eea 100644
--- a/gnu/services/desktop.scm
+++ b/gnu/services/desktop.scm
@@ -1021,7 +1021,7 @@ rules."
                         (use-modules (guix build utils))
                         (let ((directory "/tmp/.X11-unix"))
                           (mkdir-p directory)
-                          (chmod directory #o777))))))
+                          (chmod directory #o1777))))))

What do you think about it?

Thanks,

Mathieu

[bug#50563] [PATCH [0/2] gnu: GDM: Add Wayland support

[Josselin Poiret]

On Wednesday, September 29th, 2021 at 12:10 PM, Mathieu Othacehe <othacehe@gnu.org> wrote:

> > Anything wrong with my integration?
> I notied that mutter was complaining that the /tmp/.X11-unix file was
> missing the sticky bit when launching the xorg-xwayland binary.
> The following patch fixes it for me:
> [snip]
> What do you think about it?
Nice find, looks like this is the perfect fix (maybe this check was introduced in a new `gnome-shell` version).
Thanks for your review and testing!
I tried messing around and everything looked like it was working as it should, with GNOME Settings reporting it was running under Wayland.

As for the ChangeLog style, I'm sorry about it. If I'm reading correctly, I missed adding which files and symbols were changed, am I right?

[bug#50563] [PATCH [0/2] gnu: GDM: Add Wayland support

[Mathieu Othacehe]

Hello,

> Nice find, looks like this is the perfect fix (maybe this check was
> introduced in a new `gnome-shell` version).

Thanks I'll probably write a proper patch then.

> As for the ChangeLog style, I'm sorry about it. If I'm reading
> correctly, I missed adding which files and symbols were changed, am I
> right?

Yeah, that was more for future contributions, I'll get this one fixed
when applying.

Now, I also tried to run Sway (by adding it to the operating-system
packages list). It is proposed in the GDM selection box at login which
is nice, however all I get is a black screen with a frozen mouse
pointer after that.

There's a bunch of errors in /var/log/messages and
/var/log/gdm/greeter.log but I'm not sure if some are relevant here.

Mathieu

[bug#50563] [PATCH [0/2] gnu: GDM: Add Wayland support

[Josselin Poiret]

On Thursday, September 30th, 2021 at 9:41 AM, Mathieu Othacehe <othacehe@gnu.org> wrote:

> Now, I also tried to run Sway (by adding it to the operating-system
> packages list). It is proposed in the GDM selection box at login which
> is nice, however all I get is a black screen with a frozen mouse
> pointer after that.
> There's a bunch of errors in /var/log/messages and
> /var/log/gdm/greeter.log but I'm not sure if some are relevant here.

After looking around, this is because in the `wip-gnome40-wayland` branch the `sway` package has been upgraded to 1.6, introducing a regression with the bochs-drm driver that is used in qemu by default.
If you start qemu with `-vga virtio`, sway starts as usual.
This was reported upstream at https://github.com/swaywm/sway/issues/6244

[bug#50563] [PATCH [0/2] gnu: GDM: Add Wayland support

[Mathieu Othacehe]

Hey,

> After looking around, this is because in the `wip-gnome40-wayland` branch the
> `sway` package has been upgraded to 1.6, introducing a regression with the
> bochs-drm driver that is used in qemu by default.
> If you start qemu with `-vga virtio`, sway starts as usual.
> This was reported upstream at https://github.com/swaywm/sway/issues/6244

Oh, good catch! Running the following command works flawlessly indeed:

--8<---------------cut here---------------start------------->8---
$(./pre-inst-env guix system vm gnu/system/examples/desktop.tmpl --no-grafts --no-offload -v3 -K) -m 4096 -vga virtio
--8<---------------cut here---------------end--------------->8---

Thanks,

Mathieu

[bug#50563] [PATCH [0/2] gnu: GDM: Add Wayland support

[Mathieu Othacehe]

Hello,

> +;; Wrapper script for Wayland sessions, similar to Xsession.
> +;; Used to setup the environment.
> +(define gdm-wayland-session-wrapper
> +  (program-file
> +   "gdm-wayland-session-wrapper"
> +   #~((let* ((user (getpw (getuid)))
> +	    (name (passwd:name user))
> +	    (shell (passwd:shell user))
> +	    (args (cdr (command-line))))
> +        (if (string=? name "gdm")
> +	    (apply execl (cons (car args) args))
> +	    (execl shell shell "--login" "-c" (string-join args)))))))

I'm not sure to get perfectly the role of this wrapper, could you
please clarify it?

It looks like nix is dealing differently with the session starting,
without using a dedicated script:

https://github.com/NixOS/nixpkgs/blob/master/pkgs/desktops/gnome/core/gdm/fix-paths.patch

Thanks,

Mathieu

[bug#50563] [PATCH [0/2] gnu: GDM: Add Wayland support

[Josselin Poiret]

Hello,

On Friday, October 1st, 2021 at 9:37 AM, Mathieu Othacehe <othacehe@gnu.org> wrote:
> I'm not sure to get perfectly the role of this wrapper, could you
> please clarify it?

Simply put, when display managers (on Guix) start an X session, they are all configured to use a generic Guix-specific wrapper script, a `xinitrc`.
This feature predates Guix of course, and is supported by all display managers afaik. `xinitrc` is defined in `gnu/services/xorg.scm` and is the generic Guix wrapper.
Notice that most importantly, it runs the window manager inside a login shell, which thus inherits the right environment variables that are set by default in `/etc/profile` (unless of course `/etc/profile` isn't sourced by the login shell, but then the user is on his own).

So we would like to do the same with Wayland, however since Wayland compositors are just single programs that need to be launched, most display managers used to simply start the compositors without doing anything else. This is still the behaviour of GDM, whereas for example SDDM or Slim (at least in Guix) already support wrapping those in some scripts. Here, I just define a generic script that launches sessions inside a login shell, akin to the default `xinitrc`. The check for the `gdm` user is that the GDM graphical display is launched through... GDM itself, and thus is handled like the other Wayland sessions; but since the `gdm` user doesn't have a login shell, this wouldn't work.

> It looks like nix is dealing differently with the session starting,
> without using a dedicated script:
> https://github.com/NixOS/nixpkgs/blob/master/pkgs/desktops/gnome/core/gdm/fix-paths.patch

From my understanding of https://github.com/NixOS/nixpkgs/issues/109546, they're still trying to deal with this generic issue (ie. they haven't patched in wrapper support in GDM).
See https://github.com/NixOS/nixpkgs/issues/109542 for an example of a bug that stems from it.

Josselin

[bug#50563] [PATCH [0/2] gnu: GDM: Add Wayland support

[Mathieu Othacehe]

> the default `xinitrc`. The check for the `gdm` user is that the GDM graphical
> display is launched through... GDM itself, and thus is handled like the other
> Wayland sessions; but since the `gdm` user doesn't have a login shell, this
> wouldn't work.

I see that for explaining! This would deserve a comment I think, could
you please send a v2 for the second patch?

That's unrelated, but what's your take on enabling wayland by default on
GDM, like some other distributions? Just ran a quick search and it looks
like it could be problematic for Nvidia users.

Thanks,

Mathieu

[bug#50563] [PATCH [0/2] gnu: GDM: Add Wayland support

[Josselin Poiret]

On Friday, October 1st, 2021 at 9:16 AM, Mathieu Othacehe <othacehe@gnu.org> wrote:
> I see that for explaining! This would deserve a comment I think, could
> you please send a v2 for the second patch?

* gnu/packages/patches/gdm-wayland-session-wrapper-from-env.patch: Patch GDM to support launching a wrapper script for Wayland sessions.
* gnu/services/xorg.scm (gdm-configuration): Add `wayland-session` in `gdm-configuration` to
specify the wrapper to use.
* gnu/services/xorg.scm (gdm-wayland-session-wrapper): Add default wrapper that runs non-GDM sessions through a login shell (based
on the `xinitrc`).
* doc/guix.texi: Update the documentation with those changes.
---
 doc/guix.texi                                 |  4 +++
 gnu/packages/gnome.scm                        |  3 +-
 ...gdm-wayland-session-wrapper-from-env.patch | 35 +++++++++++++++++++
 gnu/services/xorg.scm                         | 25 +++++++++++--
 4 files changed, 64 insertions(+), 3 deletions(-)
 create mode 100644 gnu/packages/patches/gdm-wayland-session-wrapper-from-env.patch

diff --git a/doc/guix.texi b/doc/guix.texi
index 9e80a2c397..21c1fc04e1 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -18201,6 +18201,10 @@ The GDM package to use.

 @item @code{wayland?} (default: @code{#f})
 When true, enables Wayland in GDM, necessary to use Wayland sessions.
+
+@item @code{wayland-session} (default: @code{gdm-wayland-session-wrapper})
+The Wayland session wrapper to use, needed to setup the
+environment.
 @end table
 @end deftp

diff --git a/gnu/packages/gnome.scm b/gnu/packages/gnome.scm
index f155867dfc..ca4d00917d 100644
--- a/gnu/packages/gnome.scm
+++ b/gnu/packages/gnome.scm
@@ -8112,7 +8112,8 @@ library.")
                (base32
                 "1lyqvcwxhwxklbxn4xjswjzr6fhjix6h28mi9ypn34wdm9bzcpg8"))
               (patches (search-patches "gdm-default-session.patch"
-                                       "gdm-remove-hardcoded-xwayland-path.patch"))))
+                                       "gdm-remove-hardcoded-xwayland-path.patch"
+                                       "gdm-wayland-session-wrapper-from-env.patch"))))
     (build-system glib-or-gtk-build-system)
     (arguments
      '(#:configure-flags
diff --git a/gnu/packages/patches/gdm-wayland-session-wrapper-from-env.patch b/gnu/packages/patches/gdm-wayland-session-wrapper-from-env.patch
new file mode 100644
index 0000000000..ca1af557ef
--- /dev/null
+++ b/gnu/packages/patches/gdm-wayland-session-wrapper-from-env.patch
@@ -0,0 +1,35 @@
+Get wayland-session wrapper from environment
+
+---
+ daemon/gdm-session.c | 6 ++++--
+ 1 file changed, 4 insertions(+), 2 deletions(-)
+
+diff --git a/daemon/gdm-session.c b/daemon/gdm-session.c
+index 4e303e70..1deca4e9 100644
+--- a/daemon/gdm-session.c
++++ b/daemon/gdm-session.c
+@@ -2888,8 +2888,9 @@ gdm_session_start_session (GdmSession *self,
+                                                            allow_remote_connections? "--allow-remote-connections " : "",
+                                                            command);
+                         } else {
+-                                program = g_strdup_printf (LIBEXECDIR "/gdm-wayland-session %s\"%s\"",
++                                program = g_strdup_printf (LIBEXECDIR "/gdm-wayland-session %s\"%s %s\"",
+                                                            register_session ? "--register-session " : "",
++                                                           g_getenv ("GDM_WAYLAND_SESSION"),
+                                                            command);
+                         }
+                 } else if (run_xsession_script) {
+@@ -2906,8 +2907,9 @@ gdm_session_start_session (GdmSession *self,
+                                                            register_session ? "--register-session " : "",
+                                                            self->selected_program);
+                         } else {
+-                                program = g_strdup_printf (LIBEXECDIR "/gdm-wayland-session %s\"%s\"",
++                                program = g_strdup_printf (LIBEXECDIR "/gdm-wayland-session %s\"%s %s\"",
+                                                            register_session ? "--register-session " : "",
++                                                           g_getenv ("GDM_WAYLAND_SESSION"),
+                                                            self->selected_program);
+                         }
+                 } else {
+--
+2.33.0
+
diff --git a/gnu/services/xorg.scm b/gnu/services/xorg.scm
index fe25168a58..122dd14ae2 100644
--- a/gnu/services/xorg.scm
+++ b/gnu/services/xorg.scm
@@ -869,6 +869,23 @@ the GNOME desktop environment.")
        (apply execl (string-append #$dbus "/bin/dbus-daemon")
               (program-arguments)))))

+;; Wrapper script for Wayland sessions, similar to Xsession. See `xinitrc`.
+;; By default, launches the specified session through a login shell.
+;; With default Guix configuration, this should source /etc/profile,
+;; setting up Guix profile environment variables.
+;; However, gdm launches its own graphical session through the same method, so
+;; we need to ignore this case, since `gdm` doesn't have a login shell.
+(define gdm-wayland-session-wrapper
+  (program-file
+   "gdm-wayland-session-wrapper"
+   #~((let* ((user (getpw (getuid)))
+	    (name (passwd:name user))
+	    (shell (passwd:shell user))
+	    (args (cdr (command-line))))
+        (if (string=? name "gdm")
+	    (apply execl (cons (car args) args))
+	    (execl shell shell "--login" "-c" (string-join args)))))))
+
 (define-record-type* <gdm-configuration>
   gdm-configuration make-gdm-configuration
   gdm-configuration?
@@ -884,7 +901,8 @@ the GNOME desktop environment.")
                       (default (xorg-configuration)))
   (x-session gdm-configuration-x-session
              (default (xinitrc)))
-  (wayland? gdm-configuration-wayland? (default #f)))
+  (wayland? gdm-configuration-wayland? (default #f))
+  (wayland-session gdm-configuration-wayland-session (default gdm-wayland-session-wrapper)))

 (define (gdm-configuration-file config)
   (mixed-text-file "gdm-custom.conf"
@@ -982,7 +1000,10 @@ the GNOME desktop environment.")
                            ;; Add XCURSOR_PATH so that mutter can find its cursors.
                            ;; gdm doesn't login so doesn't source the corresponding
                            ;; line in /etc/profile
-                           "XCURSOR_PATH=/run/current-system/profile/share/icons"))))
+                           "XCURSOR_PATH=/run/current-system/profile/share/icons"
+                           (string-append
+                            "GDM_WAYLAND_SESSION="
+                            #$(gdm-configuration-wayland-session config))))))
          (stop #~(make-kill-destructor))
          (respawn? #t))))

--
2.33.0

> That's unrelated, but what's your take on enabling wayland by default on
> GDM, like some other distributions? Just ran a quick search and it looks
> like it could be problematic for Nvidia users.

I'd be mostly in favor of it, as this makes the experience smoother when trying to use a Wayland compositor "out-of-the-box" (sway and such are getting quite popular).
For Nvidia users, they mostly are aware of the driver shortcomings (and it seems that the incompatibility will soon disappear anyway),
maybe a short heads-up in the documentation would suffice.

Thanks again for the review,
Josselin

bug#50563: [PATCH [0/2] gnu: GDM: Add Wayland support

[Mathieu Othacehe]

Hey,

Thanks for the v2, I applied it on the core-updates-frozen branch
because that's where it tested it. It should soon be merged in the
master branch.

I edited the patches to add your copyrights on top of the edited
files. I also wrapped a few lines and edited the commit messages.

>> That's unrelated, but what's your take on enabling wayland by default on
>> GDM, like some other distributions? Just ran a quick search and it looks
>> like it could be problematic for Nvidia users.
>
> I'd be mostly in favor of it, as this makes the experience smoother
> when trying to use a Wayland compositor "out-of-the-box" (sway and
> such are getting quite popular).  For Nvidia users, they mostly are
> aware of the driver shortcomings (and it seems that the
> incompatibility will soon disappear anyway), maybe a short heads-up in
> the documentation would suffice.

OK so we are on the same page. Do you think you could send a patch
enabling Wayland by default for GDM and the associated documentation
update :)?

Thanks for your work on that topic,

Mathieu