From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001

From: Hans de Goede <hdegoede@redhat.com>

Date: Wed, 22 Jul 2020 14:03:42 +0200

Subject: [PATCH] Add systemd integration scripts to make "systemctl reboot

 --boot-loader-menu=xxx" work with grub

This commit adds a number of scripts / config files to make

"systemctl reboot --boot-loader-menu=xxx" work with grub:

1. /lib/systemd/system/systemd-logind.service.d/10-grub.conf

This sets SYSTEMD_REBOOT_TO_BOOT_LOADER_MENU in the env. for logind,

indicating that the boot-loader which is used supports this feature, see:

https://github.com/systemd/systemd/blob/master/docs/ENVIRONMENT.md

2. /lib/systemd/system/grub-systemd-integration.service

   /lib/systemd/system/reboot.target.wants/grub-systemd-integration.service ->

     ../grub-systemd-integration.service

   /usr/libexec/grub/grub-systemd-integration.sh

The symlink in the .wants dir causes the added service file to be started

by systemd just before rebooting the system.

If /run/systemd/reboot-to-boot-loader-menu exist then the service will run

the grub-systemd-integration.sh script.

This script sets the new menu_show_once_timeout grubenv variable to the

requested timeout in seconds.

3. /etc/grub.d/14_menu_show_once

This new grub-mkconfig snippet adds the necessary code to the generated

grub.conf to honor the new menu_show_once_timeout variable, and to

automatically clear it after consuming it.

Note the service and libexec script use grub-systemd-integration as name

because in the future they may be used to add further integration with

systemctl reboot --foo options, e.g. support for --boot-loader-entry=NAME.

A few notes about upstreaming this patch from the rhboot grub2 fork:

1. I have deliberately put the grub.conf bits for this in a new / separate

   grub-mkconfig snippet generator for easy upstreaming

2. Even though the commit message mentions the .wants symlink for the .service

   I have been unable to come up with a clean way to do this at "make install"

   time, this should be fixed before upstreaming.

Downstream notes:

1. Since make install does not add the .wants symlink, this needs to be done

   in grub2.spec %install

2. This is keeping support for the "old" Fedora specific menu_show_once env

   variable, which has a hardcoded timeout of 60 sec in 12_menu_auto_hide in

   place for now. This can be dropped (eventually) in a follow-up patch once

   GNOME has been converted to use the systemd dbus API equivalent of

   "systemctl reboot --boot-loader-menu=xxx".

Signed-off-by: Hans de Goede <hdegoede@redhat.com>

---

 Makefile.util.def                                | 27 ++++++++++++++++++++++++

 conf/Makefile.common                             |  6 ++++++

 util/grub.d/14_menu_show_once.in                 | 13 ++++++++++++

 util/systemd/10-grub-logind-service.conf.in      |  2 ++

 util/systemd/grub-systemd-integration.service.in |  8 +++++++

 util/systemd/systemd-integration.sh.in           |  6 ++++++

 6 files changed, 62 insertions(+)

 create mode 100755 util/grub.d/14_menu_show_once.in

 create mode 100644 util/systemd/10-grub-logind-service.conf.in

 create mode 100644 util/systemd/grub-systemd-integration.service.in

 create mode 100644 util/systemd/systemd-integration.sh.in

diff --git a/Makefile.util.def b/Makefile.util.def

index 2e6ad979c3..9927c2cfd6 100644

--- a/Makefile.util.def

+++ b/Makefile.util.def

@@ -470,6 +470,12 @@ script = {

   installdir = grubconf;

 };

+script = {

+  name = '14_menu_show_once';

+  common = util/grub.d/14_menu_show_once.in;

+  installdir = grubconf;

+};

+

 script = {

   name = '01_users';

   common = util/grub.d/01_users.in;

@@ -569,6 +575,27 @@ script = {

   installdir = grubconf;

 };

+script = {

+  name = 'grub-systemd-integration.service';

+  common = util/systemd/grub-systemd-integration.service.in;

+  installdir = systemdunit;

+  condition = COND_HOST_LINUX;

+};

+

+script = {

+  name = 'systemd-integration.sh';

+  common = util/systemd/systemd-integration.sh.in;

+  installdir = grublibexec;

+  condition = COND_HOST_LINUX;

+};

+

+script = {

+  name = '10-grub-logind-service.conf';

+  common = util/systemd/10-grub-logind-service.conf.in;

+  installdir = systemd_logind_service_d;

+  condition = COND_HOST_LINUX;

+};

+

 program = {

   mansection = 1;

   name = grub-mkrescue;

diff --git a/conf/Makefile.common b/conf/Makefile.common

index 0647c53b91..9fe5863b2d 100644

--- a/conf/Makefile.common

+++ b/conf/Makefile.common

@@ -63,8 +63,11 @@ CCASFLAGS_LIBRARY = $(UTILS_CCASFLAGS)

 # Other variables

 grubconfdir = $(sysconfdir)/grub.d

+grublibexecdir = $(libexecdir)/$(grubdirname)

 platformdir = $(pkglibdir)/$(target_cpu)-$(platform)

 starfielddir = $(pkgdatadir)/themes/starfield

+systemdunitdir = ${prefix}/lib/systemd/system

+systemd_logind_service_ddir = $(systemdunitdir)/systemd-logind.service.d

 CFLAGS_GNULIB = -Wno-undef -Wno-unused -Wno-unused-parameter -Wno-redundant-decls -Wno-unreachable-code -Werror=trampolines -fno-trampolines

 CPPFLAGS_GNULIB = -I$(top_builddir)/grub-core/lib/gnulib -I$(top_srcdir)/grub-core/lib/gnulib

@@ -121,6 +124,9 @@ noinst_LIBRARIES =

 dist_noinst_DATA =

 platform_SCRIPTS =

 platform_PROGRAMS =

+grublibexec_SCRIPTS =

+systemdunit_SCRIPTS =

+systemd_logind_service_d_SCRIPTS =

 TESTS =

 EXTRA_DIST =

diff --git a/util/grub.d/14_menu_show_once.in b/util/grub.d/14_menu_show_once.in

new file mode 100755

index 0000000000..1cd7f36142

--- /dev/null

+++ b/util/grub.d/14_menu_show_once.in

@@ -0,0 +1,13 @@

+#! /bin/sh

+# Force the menu to be shown once, with a timeout of ${menu_show_once_timeout}

+# if requested by ${menu_show_once_timeout} being set in the env.

+cat << EOF

+if [ x\$feature_timeout_style = xy ]; then

+  if [ "\${menu_show_once_timeout}" ]; then

+    set timeout_style=menu

+    set timeout="\${menu_show_once_timeout}"

+    unset menu_show_once_timeout

+    save_env menu_show_once_timeout

+  fi

+fi

+EOF

diff --git a/util/systemd/10-grub-logind-service.conf.in b/util/systemd/10-grub-logind-service.conf.in

new file mode 100644

index 0000000000..f2d4ac0073

--- /dev/null

+++ b/util/systemd/10-grub-logind-service.conf.in

@@ -0,0 +1,2 @@

+[Service]

+Environment=SYSTEMD_REBOOT_TO_BOOT_LOADER_MENU=true

diff --git a/util/systemd/grub-systemd-integration.service.in b/util/systemd/grub-systemd-integration.service.in

new file mode 100644

index 0000000000..c81fb594ce

--- /dev/null

+++ b/util/systemd/grub-systemd-integration.service.in

@@ -0,0 +1,8 @@

+[Unit]

+Description=Grub2 systemctl reboot --boot-loader-menu=... support

+Before=umount.target systemd-reboot.service

+DefaultDependencies=no

+ConditionPathExists=/run/systemd/reboot-to-boot-loader-menu

+

+[Service]

+ExecStart=@libexecdir@/@grubdirname@/systemd-integration.sh

diff --git a/util/systemd/systemd-integration.sh.in b/util/systemd/systemd-integration.sh.in

new file mode 100644

index 0000000000..dc1218597b

--- /dev/null

+++ b/util/systemd/systemd-integration.sh.in

@@ -0,0 +1,6 @@

+#!/bin/sh

+

+TIMEOUT_USEC=$(cat /run/systemd/reboot-to-boot-loader-menu)

+TIMEOUT=$(((TIMEOUT_USEC + 500000) / 1000000))

+

+@grub_editenv@ - set menu_show_once_timeout=$TIMEOUT