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downgrade.sh
#!/usr/bin/bash
#
# downgrade: downgrade packages using pacman's database and system log files
#
# Copyright (c) 2008 locci <carlocci_at_gmail_dot_com>
# Copyright (c) 2008-2016 Pacman Development Team <pacman-dev@archlinux.org>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
shopt -s extglob
shopt -s nullglob
declare -r myname='downgrade'
declare -r myver='5.0.1'
USE_COLOR='y'
pac_arg=''
QUIET=0
LAST_TRANSACTIONS=10
# gettext initialization
export TEXTDOMAIN='pacman'
export TEXTDOMAINDIR='@localedir@'
# Determine whether we have gettext; make it a no-op if we do not
if ! type -p gettext >/dev/null; then
gettext() {
printf "%s\n" "$*"
}
fi
plain() {
(( QUIET )) && return
local mesg=$1; shift
printf "${BOLD} ${mesg}${ALL_OFF}\n" "$@" >&1
}
msg() {
(( QUIET )) && return
local mesg=$1; shift
printf "${GREEN}==>${ALL_OFF}${BOLD} ${mesg}${ALL_OFF}\n" "$@" >&1
}
msg2() {
(( QUIET )) && return
local mesg=$1; shift
printf "${BLUE} ->${ALL_OFF}${BOLD} ${mesg}${ALL_OFF}\n" "$@" >&1
}
ask() {
local mesg=$1; shift
printf "${BLUE}::${ALL_OFF}${BOLD} ${mesg}${ALL_OFF}" "$@" >&1
}
warning() {
local mesg=$1; shift
printf "${YELLOW}==> $(gettext "WARNING:")${ALL_OFF}${BOLD} ${mesg}${ALL_OFF}\n" "$@" >&2
}
error() {
local mesg=$1; shift
printf "${RED}==> $(gettext "ERROR:")${ALL_OFF}${BOLD} ${mesg}${ALL_OFF}\n" "$@" >&2
}
# getopt-like parser
parseopts() {
local opt= optarg= i= shortopts=$1
local -a longopts=() unused_argv=()
shift
while [[ $1 && $1 != '--' ]]; do
longopts+=("$1")
shift
done
shift
longoptmatch() {
local o longmatch=()
for o in "${longopts[@]}"; do
if [[ ${o%:} = "$1" ]]; then
longmatch=("$o")
break
fi
[[ ${o%:} = "$1"* ]] && longmatch+=("$o")
done
case ${#longmatch[*]} in
1)
# success, override with opt and return arg req (0 == none, 1 == required)
opt=${longmatch%:}
if [[ $longmatch = *: ]]; then
return 1
else
return 0
fi ;;
0)
# fail, no match found
return 255 ;;
*)
# fail, ambiguous match
printf "downgrade: $(gettext "option '%s' is ambiguous; possibilities:")" "--$1"
printf " '%s'" "${longmatch[@]%:}"
printf '\n'
return 254 ;;
esac >&2
}
while (( $# )); do
case $1 in
--) # explicit end of options
shift
break
;;
-[!-]*) # short option
for (( i = 1; i < ${#1}; i++ )); do
opt=${1:i:1}
# option doesn't exist
if [[ $shortopts != *$opt* ]]; then
printf "downgrade: $(gettext "invalid option") -- '%s'\n" "$opt" >&2
OPTRET=(--)
return 1
fi
OPTRET+=("-$opt")
# option requires optarg
if [[ $shortopts = *$opt:* ]]; then
# if we're not at the end of the option chunk, the rest is the optarg
if (( i < ${#1} - 1 )); then
OPTRET+=("${1:i+1}")
break
# if we're at the end, grab the the next positional, if it exists
elif (( i == ${#1} - 1 )) && [[ $2 ]]; then
OPTRET+=("$2")
shift
break
# parse failure
else
printf "downgrade: $(gettext "option requires an argument") -- '%s'\n" "$opt" >&2
OPTRET=(--)
return 1
fi
fi
done
;;
--?*=*|--?*) # long option
IFS='=' read -r opt optarg <<< "${1#--}"
longoptmatch "$opt"
case $? in
0)
# parse failure
if [[ $optarg ]]; then
printf "downgrade: $(gettext "option '%s' does not allow an argument")\n" "--$opt" >&2
OPTRET=(--)
return 1
# --longopt
else
OPTRET+=("--$opt")
fi
;;
1)
# --longopt=optarg
if [[ $optarg ]]; then
OPTRET+=("--$opt" "$optarg")
# --longopt optarg
elif [[ $2 ]]; then
OPTRET+=("--$opt" "$2" )
shift
# parse failure
else
printf "downgrade: $(gettext "option '%s' requires an argument")\n" "--$opt" >&2
OPTRET=(--)
return 1
fi
;;
254)
# ambiguous option -- error was reported for us by longoptmatch()
OPTRET=(--)
return 1
;;
255)
# parse failure
printf "downgrade: $(gettext "invalid option") '--%s'\n" "$opt" >&2
OPTRET=(--)
return 1
;;
esac
;;
*) # non-option arg encountered, add it as a parameter
unused_argv+=("$1")
;;
esac
shift
done
# add end-of-opt terminator and any leftover positional parameters
OPTRET+=('--' "${unused_argv[@]}" "$@")
unset longoptmatch
return 0
}
# Print usage information
usage() {
printf "%s (pacman) %s\n" "$myname" "$myver"
echo
printf -- "$(gettext "Downgrade packages using pacman's database and system log files")\n"
echo
printf -- "$(gettext "Usage: %s [options] [package(s)]")\n" "$0"
echo
printf -- "$(gettext "Options:")\n"
printf -- "$(gettext " -h, --help Show this help message and exit")\n"
printf -- "$(gettext " -q, --quiet Silence most of the status reporting; not suitable for interactive use")\n"
printf -- "$(gettext " -m, --nocolor Disable colorized output messages")\n"
printf -- "$(gettext " -n, --number <n> List the last <n> transactions (defaults to %s)")\n" "$LAST_TRANSACTIONS"
printf -- "$(gettext " --needed Do not reinstall the targets that are already up-to-date")\n"
printf -- "$(gettext " --noconfirm Bypass any and all “Are you sure?” messages")\n"
echo
printf -- "$(gettext "Examples:")"
printf -- " %s --needed\n" "$myname"
printf -- " %s linux linux-headers\n" "$myname"
printf -- " %s --noconfirm binutils\n" "$myname"
echo
}
# Print version information
version() {
printf "%s %s\n" "$myname" "$myver"
echo 'Copyright (C) 2016 Gordian Edenhofer <gordian.edenhofer@gmail.com>'
echo 'Copyright (C) 2008-2016 Pacman Development Team <pacman-dev@archlinux.org>'
}
# Printing the usage information takes precedence over every other parameter
for option in "$@"; do
[[ $option == "-h" || $option == "--help" ]] && usage && exit 0
done
# Parse arguments
OPT_SHORT='qmn:v'
OPT_LONG=('quiet' 'nocolor' 'number:' 'needed' 'noconfirm' 'version')
if ! parseopts "$OPT_SHORT" "${OPT_LONG[@]}" -- "$@"; then
usage
exit 1
fi
set -- "${OPTRET[@]}"
unset OPT_SHORT OPT_LONG OPTRET
while :; do
case "$1" in
-q|--quiet)
QUIET=1 ;;
-m|--nocolor)
USE_COLOR='n' ;;
-n|--number)
LAST_TRANSACTIONS="$2" ;;
--needed)
pac_arg="${pac_arg} --needed" ;;
--noconfirm)
pac_arg="${pac_arg} --nocofirm" ;;
-v|--version)
version
exit 0 ;;
--)
shift
break 2 ;;
esac
shift
done
# Configure colored output
# check if messages are to be printed using color
unset ALL_OFF BOLD BLUE GREEN RED YELLOW
if [[ -t 2 && ! $USE_COLOR = "n" ]]; then
# prefer terminal safe colored and bold text when tput is supported
if tput setaf 0 &>/dev/null; then
ALL_OFF="$(tput sgr0)"
BOLD="$(tput bold)"
BLUE="${BOLD}$(tput setaf 4)"
GREEN="${BOLD}$(tput setaf 2)"
RED="${BOLD}$(tput setaf 1)"
YELLOW="${BOLD}$(tput setaf 3)"
else
ALL_OFF="\e[1;0m"
BOLD="\e[1;1m"
BLUE="${BOLD}\e[1;34m"
GREEN="${BOLD}\e[1;32m"
RED="${BOLD}\e[1;31m"
YELLOW="${BOLD}\e[1;33m"
fi
fi
readonly ALL_OFF BOLD BLUE GREEN RED YELLOW
# Source environmental variables and specify fallbacks
if [[ ! -r /etc/pacman.conf ]]; then
error "unable to read /etc/pacman.conf"
exit 1
fi
eval $(awk '/LogFile/ {print $1$2$3}' /etc/pacman.conf)
pac_LogFile="${LogFile:-"/var/log/pacman.log"}"
eval $(awk '/CacheDir/ {print $1$2$3}' /etc/pacman.conf)
pac_CacheDir="${LogFile:-"/var/cache/pacman/pkg"}"
if [[ ! -r /etc/makepkg.conf ]]; then
error "unable to read /etc/makepkg.conf"
exit 1
fi
source "/etc/makepkg.conf"
if [[ -r ~/.makepkg.conf ]]; then
source ~/.makepkg.conf
fi
# Retrieve the list of packages to be assembled and break if none was specified
pkg_list=($*)
if [[ ${#pkg_list[@]} == 0 ]]; then
msg "Select one of the following transactions:"
# Read in log file as array
mapfile -t lines <"${pac_LogFile}"
# Query the date to which to downgrade to
transaction_count=0
transaction_line=("${#lines[@]}")
for (( idx=${#lines[@]}-1; idx>=0; idx-- )); do
# Print transaction list with their id
if [[ "${lines[idx]}" =~ "[ALPM] transaction started" ]]; then
for (( n=${transaction_line[-1]}; n>=idx; n-- )); do
# Skip transactions which do not qualify as upgrade or downgrade
if [[ "${lines[n]}" =~ "[ALPM] "(upgraded|downgraded)" " ]]; then
((transaction_count++))
transaction_line[transaction_count]="${idx}"
QUIET=0 msg2 "${transaction_count}\t: date $(echo "${lines[idx]}" | awk '{ print $1 " " $2 }')\tline ${transaction_line[transaction_count]}"
break
fi
done
fi
(( "${transaction_count}" == "${LAST_TRANSACTIONS}" )) && break
done
ask "Transaction number: "
read user_input
if [[ -z "${user_input##*[!0-9]*}" ]] || (( user_input > LAST_TRANSACTIONS || user_input == 0 )); then
error "'${user_input}' is not a valid choice..."
exit 1
fi
# Assemble a list of packages to downgrade
downgrade_pkgname=()
downgrade_pkgver=()
downgrade_pkgfile=()
for (( idx=${#lines[@]}-1; idx>=0; idx-- )); do
if (( idx == ${transaction_line[user_input]} )); then
break
elif [[ "${lines[idx]}" =~ "[ALPM] "(upgraded|downgraded)" " ]]; then
# Append package to list
downgrade_pkgname+=("$(echo "${lines[idx]}" | awk '{ print $5 }')")
downgrade_pkgver+=("$(echo "${lines[idx]}" | awk '{ print substr($6,2) }')")
if [[ -f "$(find "${pac_CacheDir}" -maxdepth 1 -type f -name "${downgrade_pkgname[-1]}-${downgrade_pkgver[-1]}-*" -print -quit)" ]]; then
downgrade_pkgfile+=("$(find "${pac_CacheDir}" -maxdepth 1 -type f -name "${downgrade_pkgname[-1]}-${downgrade_pkgver[-1]}-*" -print -quit)")
elif [[ -n "${PKGDEST}" && -f "$(find "${PKGDEST}" -maxdepth 1 -type f -name "${downgrade_pkgname[-1]}-${downgrade_pkgver[-1]}-*" -print -quit)" ]]; then
downgrade_pkgfile+=("$(find "${PKGDEST}" -maxdepth 1 -type f -name "${downgrade_pkgname[-1]}-${downgrade_pkgver[-1]}-*" -print -quit)")
else
downgrade_pkgfile+=("")
fi
fi
done
# Safely set duplicates to null in package lists
for (( idx=${#downgrade_pkgname[@]}-1; idx>=0; idx-- )); do
for (( n=0; n<idx; n++ )); do
if [[ "${downgrade_pkgname[n]}" == "${downgrade_pkgname[idx]}" ]]; then
downgrade_pkgname[${n}]=""
downgrade_pkgver[${n}]=""
downgrade_pkgfile[${n}]=""
fi
done
done
else
# Loop over given packages and ask for a version
for pkgname in "${pkg_list[@]}"; do
# Scan system for available package versions and skip if none were found
if [[ -n "${PKGDEST}" ]]; then
mapfile -t pkg_versions < <(find "${pac_CacheDir}" "${PKGDEST}" -maxdepth 1 -type f -regextype sed -regex ".*/${pkgname}-[^\-]\+-[^\-]\+-[^\-]\+\.pkg\.tar.*" -print)
else
mapfile -t pkg_versions < <(find "${pac_CacheDir}" -maxdepth 1 -type f -regextype sed -regex ".*/${pkgname}-[^\-]\+-[^\-]\+-[^\-]\+\.pkg\.tar.*" -print)
fi
if [[ "${#pkg_versions[@]}" -eq 0 ]]; then
error "No package baring the name '${pkgname}' was found... skipping"
continue
fi
# TODO: Add ArchLinuxArchive support
# Sort the version array
pkg_versions=($(printf '%s\n' "${pkg_versions[@]}" | sort))
# Query the version to which to downgrade
msg "Select one of the following versions for ${pkgname}:"
pkg_count=0
for pkgfile in "${!pkg_versions[@]}"; do
msg2 "$((pkg_count+1))\t: $(basename "${pkg_versions[pkg_count]}" | sed 's/-[^-]*.pkg.tar..*//g')\tfile ${pkg_versions[pkg_count]}"
((pkg_count++))
done
ask "Item number: "
read user_input
if [[ -z "${user_input##*[!0-9]*}" ]] || (( user_input > pkg_count || user_input == 0 )); then
error "'${user_input}' is not a valid choice..."
continue
fi
downgrade_pkgfile+=("${pkg_versions[$((user_input-1))]}")
done
fi
# Strip null elements from file array
for i in "${!downgrade_pkgfile[@]}"; do
[[ -z "${downgrade_pkgfile[i]}" ]] && unset "downgrade_pkgfile[$i]"
done
# Invoke pacman if matches were found
if [[ -z "${downgrade_pkgfile[@]}" ]]; then
msg "Nothing to downgrade..."
else
msg "Starting pacman..."
# Gain privileges using sudo if not running as root
if [[ $EUID -eq 0 ]]; then
pacman -U ${pac_arg} "${downgrade_pkgfile[@]}"
else
if ! which sudo &>/dev/null ; then
error "Cannot find the sudo binary!"
error "${myname} requires root privileges. Either install \"sudo\" or run as root."
exit 1
else
sudo pacman -U ${pac_arg} "${downgrade_pkgfile[@]}"
fi
fi
fi
msg "Done."
exit 0
# vim: set noet:
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