[3006.x] Make deb scripts more compliant with Debian policy

[baby-gnu]

What does this PR do?

• make the deb scripts manage systemd status during upgrade
• improve script compliance with debian policy based on dh-make examples

What issues does this PR fix or reference?

Fixes #66507

Previous Behavior

When upgrading debian salt packages, the current status of the services are not managed:

• previously disabled packages became enable
• masked packages make the upgrade fail

Status of the services before upgrade

○ salt-master.service - The Salt Master Server
     Loaded: loaded (/lib/systemd/system/salt-master.service; disabled; preset: enabled)
     Active: inactive (dead)
       Docs: man:salt-master(1)
             file:///usr/share/doc/salt/html/contents.html
             https://docs.saltproject.io/en/latest/contents.html

○ salt-minion.service - The Salt Minion
     Loaded: loaded (/lib/systemd/system/salt-minion.service; disabled; preset: enabled)
     Active: inactive (dead)
       Docs: man:salt-minion(1)
             file:///usr/share/doc/salt/html/contents.html
             https://docs.saltproject.io/en/latest/contents.html

○ salt-api.service
     Loaded: masked (Reason: Unit salt-api.service is masked.)
     Active: inactive (dead)

Error log during upgrade

Status of the services after failed upgrade

○ salt-master.service - The Salt Master Server
     Loaded: loaded (/lib/systemd/system/salt-master.service; enabled; preset: enabled)
     Active: inactive (dead)
       Docs: man:salt-master(1)
             file:///usr/share/doc/salt/html/contents.html
             https://docs.saltproject.io/en/latest/contents.html

○ salt-minion.service - The Salt Minion
     Loaded: loaded (/lib/systemd/system/salt-minion.service; disabled; preset: enabled)
     Active: inactive (dead)
       Docs: man:salt-minion(1)
             file:///usr/share/doc/salt/html/contents.html
             https://docs.saltproject.io/en/latest/contents.html

○ salt-api.service
     Loaded: masked (Reason: Unit salt-api.service is masked.)
     Active: inactive (dead)

New Behavior

The upgrade should work with masked services and keep previous status after upgrade.

I can't test it because I did not find the way to build custom packages to test

Merge requirements satisfied?

[NOTICE] Bug fixes or features added to Salt require tests.

• Docs
• Changelog - https://docs.saltproject.io/en/master/topics/development/changelog.html
• Tests written/updated

Commits signed with GPG?

Yes

Please review Salt's Contributing Guide for best practices, including the
PR Guidelines.

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[baby-gnu]

To me, my PR is working fire, the generated scripts now looks like this:

salt-master.preinst

#!/bin/sh
# preinst script for salt-package.
#
# See: dh_installdeb(1).

set -e

# Summary of how this script can be called:
#        * <new-preinst> 'install'
#        * <new-preinst> 'install' <old-version>
#        * <new-preinst> 'upgrade' <old-version>
#        * <old-preinst> 'abort-upgrade' <new-version>
# for details, see https://www.debian.org/doc/debian-policy/ or
# the debian-policy package.


case "$1" in
  install|upgrade)
    [ -z "$SALT_HOME" ] && SALT_HOME=/opt/saltstack/salt
    [ -z "$SALT_USER" ] && SALT_USER=salt
    [ -z "$SALT_NAME" ] && SALT_NAME="Salt"
    [ -z "$SALT_GROUP" ] && SALT_GROUP=salt
    PY_VER=$(/opt/saltstack/salt/bin/python3 -c "import sys; sys.stdout.write('{}.{}'.format(*sys.version_info)); sys.stdout.flush();")

    # Reset permissions to fix previous installs
    find ${SALT_HOME} /etc/salt /var/log/salt /var/cache/salt /var/run/salt \
        \! \( -path /etc/salt/cloud.deploy.d\* -o -path /var/log/salt/cloud -o -path /opt/saltstack/salt/lib/python${PY_VER}/site-packages/salt/cloud/deploy\* \) -a \
        \( -user ${SALT_USER} -o -group ${SALT_GROUP} \) -exec chown root:root \{\} \;

  # remove incorrectly installed ufw salt-master directory - issue 57712
  test -d /etc/ufw/applications.d/salt-master && rm -rf /etc/ufw/applications.d/salt-master || /bin/true

  ;;

  abort-upgrade)
  ;;

  *)
    echo "preinst called with unknown argument '$1'" >&2
    exit 1
  ;;
esac

# dh_installdeb will replace this with shell code automatically
# generated by other debhelper scripts.



exit 0

salt-master.postinst

#!/bin/sh
# postinst script for salt-master
#
# see: dh_installdeb(1)

set -e

# summary of how this script can be called:
#        * <postinst> `configure' <most-recently-configured-version>
#        * <old-postinst> `abort-upgrade' <new version>
#        * <conflictor's-postinst> `abort-remove' `in-favour' <package>
#          <new-version>
#        * <postinst> `abort-remove'
#        * <deconfigured's-postinst> `abort-deconfigure' `in-favour'
#          <failed-install-package> <version> `removing'
#          <conflicting-package> <version>
# for details, see https://www.debian.org/doc/debian-policy/ or
# the debian-policy package

case "$1" in
  configure)
    if [ ! -e "/var/log/salt/master" ]; then
      touch /var/log/salt/master
      chmod 640 /var/log/salt/master
    fi
    if [ ! -e "/var/log/salt/key" ]; then
      touch /var/log/salt/key
      chmod 640 /var/log/salt/key
    fi
    chown -R salt:salt /etc/salt/pki/master /etc/salt/master.d /var/log/salt/master /var/log/salt/key /var/cache/salt/master /var/run/salt/master
  ;;
  abort-upgrade|abort-remove|abort-deconfigure)
  ;;

  *)
    echo "postinst called with unknown argument '$1'" >&2
    exit 1
  ;;
esac

# dh_installdeb will replace this with shell code automatically
# generated by other debhelper scripts.

# Automatically added by dh_systemd_enable/13.11.4
if [ "$1" = "configure" ] || [ "$1" = "abort-upgrade" ] || [ "$1" = "abort-deconfigure" ] || [ "$1" = "abort-remove" ] ; then
	# The following line should be removed in trixie or trixie+1
	deb-systemd-helper unmask 'salt-master.service' >/dev/null || true

	# was-enabled defaults to true, so new installations run enable.
	if deb-systemd-helper --quiet was-enabled 'salt-master.service'; then
		# Enables the unit on first installation, creates new
		# symlinks on upgrades if the unit file has changed.
		deb-systemd-helper enable 'salt-master.service' >/dev/null || true
	else
		# Update the statefile to add new symlinks (if any), which need to be
		# cleaned up on purge. Also remove old symlinks.
		deb-systemd-helper update-state 'salt-master.service' >/dev/null || true
	fi
fi
# End automatically added section
# Automatically added by dh_systemd_start/13.11.4
if [ "$1" = "configure" ] || [ "$1" = "abort-upgrade" ] || [ "$1" = "abort-deconfigure" ] || [ "$1" = "abort-remove" ] ; then
	if [ -d /run/systemd/system ]; then
		systemctl --system daemon-reload >/dev/null || true
		if [ -n "$2" ]; then
			_dh_action=restart
		else
			_dh_action=start
		fi
		deb-systemd-invoke $_dh_action 'salt-master.service' >/dev/null || true
	fi
fi
# End automatically added section


exit 0

salt-master.prerm

#!/bin/sh
set -e
# Automatically added by dh_systemd_start/13.11.4
if [ -z "${DPKG_ROOT:-}" ] && [ "$1" = remove ] && [ -d /run/systemd/system ] ; then
	deb-systemd-invoke stop 'salt-master.service' >/dev/null || true
fi
# End automatically added section

salt-master.postrm

#!/bin/sh
set -e
# Automatically added by dh_systemd_start/13.11.4
if [ "$1" = remove ] && [ -d /run/systemd/system ] ; then
	systemctl --system daemon-reload >/dev/null || true
fi
# End automatically added section
# Automatically added by dh_systemd_enable/13.11.4
if [ "$1" = "purge" ]; then
	if [ -x "/usr/bin/deb-systemd-helper" ]; then
		deb-systemd-helper purge 'salt-master.service' >/dev/null || true
	fi
fi
# End automatically added section

[baby-gnu]

I fixed the find in salt-master.preinst which do try to run on nonexistent directory if service are disabled or masked.