epm-release_downgrade

#!/bin/sh
#
# Copyright (C) 2013, 2016, 2017, 2019, 2020, 2021  Etersoft
# Copyright (C) 2013, 2016, 2017, 2019, 2020, 2021  Vitaly Lipatov <lav@etersoft.ru>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#

load_helper epm-release_upgrade

get_prev_release()
{
	local FROM="$1"
	case "$FROM" in
	"p8")
		echo "p7" ;;
	"p9")
		echo "p8" ;;
	"p10")
		echo "p9" ;;
	"c7")
		echo "c6" ;;
	"c8")
		echo "c7" ;;
	"c8.1")
		echo "c8" ;;
	"c8.2")
		echo "c8.1" ;;
	"c9")
		echo "c8.2" ;;
	"9")
		echo "10" ;;
	*)
		echo "$FROM" ;;
	esac
}

# FIXME: see epm_release_upgrade
epm_release_downgrade()
{
	assure_root
	assure_safe_run
	info "Starting upgrade/switch whole system to other release"
	info "Check also http://wiki.etersoft.ru/Admin/UpdateLinux"

	cd /tmp || fatal
	# TODO: it is possible eatmydata does not do his work
	export EPMNOEATMYDATA=1

	case $DISTRNAME in
	ALTLinux|ALTServer)
		__epm_ru_update || fatal

		# try to detect current release by repo
		if [ "$DISTRVERSION" = "Sisyphus" ] || [ -z "$DISTRVERSION" ] ; then
			local dv
			dv="$(__detect_alt_release_by_repo)"
			if [ -n "$dv" ] && [ "$dv" != "$DISTRVERSION" ] ; then
				DISTRVERSION="$dv"
				info "Detected running $DISTRNAME $DISTRVERSION (according to using repos)"
			fi
		fi

		TARGET=""
		[ -n "$3" ] && fatal "Too many args: $*"
		if [ -n "$2" ] ; then
			DISTRVERSION="$1"
			info "Force current distro version as $DISTRVERSION"
			TARGET="$2"
		elif [ -n "$1" ] ; then
			TARGET="$1"
		fi

		[ -n "$TARGET" ] || TARGET="$(get_prev_release $DISTRVERSION)"

		__alt_repofix

		__switch_alt_to_distro $DISTRVERSION $TARGET && info "Done. The system has been successfully downgraded to the previous release '$TARGET'."

		return 0
		;;
	*)
		;;
	esac

	case $PMTYPE in
	apt-rpm)
		#docmd epm update
		info "Have no idea how to downgrade $DISTRNAME"
		;;
	*-dpkg)
		assure_exists do-release-upgrade update-manager-core
		sudocmd do-release-upgrade
		;;
	packagekit)
		docmd pkcon upgrade-system "$@"
		;;
	yum-rpm)
		docmd epm install rpm yum
		sudocmd yum clean all
		# TODO
		showcmd rpm -Uvh http://mirror.yandex.ru/fedora/linux/releases/16/Fedora/x86_64/os/Packages/fedora-release-16-1.noarch.rpm
		showcmd epm Upgrade
		;;
	dnf-rpm)
		info "Check https://fedoraproject.org/wiki/DNF_system_upgrade for an additional info"
		docmd epm install dnf
		#docmd epm install epel-release yum-utils
		sudocmd dnf --refresh upgrade
		sudocmd dnf clean all
		assure_exists dnf-plugin-system-upgrade
		sudocmd dnf upgrade --refresh
		local RELEASEVER="$1"
		[ -n "$RELEASEVER" ] || RELEASEVER=$(($DISTRVERSION + 1))
		#[ -n "$RELEASEVER" ] || fatal "Run me with new version"
		confirm_info "Upgrade to $DISTRNAME/$RELEASEVER"
		sudocmd dnf system-upgrade download --refresh --releasever=$RELEASEVER
		# TODO: from docs:
		# dnf system-upgrade reboot
		# FIXME: download all packages again
		sudocmd dnf distro-sync --releasever=$RELEASEVER
		info "Run epm autoorphans to remove orphaned packages"
		;;
	urpm-rpm)
		sudocmd urpmi.removemedia -av
		# TODO
		showcmd urpmi.addmedia --distrib http://mirror.yandex.ru/mandriva/devel/2010.2/i586/
		sudocmd urpmi --auto-update --replacefiles
		;;
	zypper-rpm)
		docmd epm repolist
		# TODO
		# sudocmd zypper rr <номер_репозитория>
		showcmd rr N
		showcmd epm ar http://mirror.yandex.ru/opensuse/distribution/11.1/repo/oss 11.1oss
		showcmd zypper ref
		docmd epm update
		docmd epm install rpm zypper
		docmd epm upgrade
		;;
	pacman)
		epm Upgrade
		;;
	conary)
		epm Upgrade
		;;
	emerge)
		epm Upgrade
		;;
	guix)
		sudocmd guix pull --verbose
		;;
	*)
		fatal "Have no suitable command for $PMTYPE"
		;;
	esac

}