path: root/contrib/paccache.in

#!/bin/bash
#
# pacache - flexible pacman cache cleaning
#
# Copyright (C) 2011 Dave Reisner <dreisner@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

declare -a candidates=() cmdopts=() whitelist=() blacklist=()
declare -i delete=0 dryrun=0 filecount=0 keep=3 move=0 totalsaved=0
declare    cachedir=@localstatedir@/cache/pacman/pkg delim=$'\n' movedir= scanarch=

msg() {
        local mesg=$1; shift
        printf "==> $mesg\n" "$@"
} >&2

error() {
        local mesg=$1; shift
        printf "==> ERROR: $mesg\n" "$@"
} >&2

die() {
        error "$@"
        exit 1
}

# reads a list of files on stdin and prints out deletion candidates
pkgfilter() {
        # there's whitelist and blacklist parameters passed to this
        # script after the block of awk.

        awk -v keep="$1" -v scanarch="$2" '
        function parse_filename(filename,     parts, count, i, pkgname, arch) {

                count = split(filename, parts, "-")

                i = 1
                pkgname = parts[i++]
                while (i <= count - 3) {
                        pkgname = pkgname "-" parts[i++]
                }

                arch = substr(parts[count], 1, index(parts[count], ".") - 1)

                # filter on whitelist or blacklist
                if (wlen && !whitelist[pkgname]) return
                if (blen && blacklist[pkgname]) return

                if ("" == packages[pkgname,arch]) {
                        packages[pkgname,arch] = filename
                } else {
                        packages[pkgname,arch] = packages[pkgname,arch] SUBSEP filename
                }
        }

        BEGIN {
                # create whitelist
                wlen = ARGV[1]; delete ARGV[1]
                for (i = 2; i < 2 + wlen; i++) {
                        whitelist[ARGV[i]] = 1
                        delete ARGV[i]
                }

                # create blacklist
                blen = ARGV[i]; delete ARGV[i]
                while (i++ < ARGC) {
                        blacklist[ARGV[i]] = 1
                        delete ARGV[i]
                }

                # read package filenames
                while (getline < "/dev/stdin") {
                        parse_filename($0)
                }
        }

        END {
                for (pkglist in packages) {
                        # idx[1,2] = idx[pkgname,arch]
                        split(pkglist, idx, SUBSEP)

                        # enforce architecture match if specified
                        if (!scanarch || scanarch == idx[2]) {
                                count = split(packages[idx[1], idx[2]], pkgs, SUBSEP)
                                if (count > keep) {
                                        for(i = 1; i <= count - keep; i++) {
                                                print pkgs[i]
                                        }
                                }
                        }
                }
        }' "${@:3}"
}

size_to_human() {
        awk -v size="$1" '
        BEGIN {
                suffix[1] = "KiB"
                suffix[2] = "MiB"
                suffix[3] = "GiB"
                suffix[4] = "TiB"
                count = 1

                while (size > 1024) {
                        size /= 1024
                        count++
                }

                sizestr = sprintf("%.2f", size)
                sub(/.?0+$/, "", sizestr)
                printf("%s %s", sizestr, suffix[count])
        }'
}

runcmd() {
        if (( needsroot )); then
                msg "Privilege escalation required"
                if sudo -v &>/dev/null && sudo -l &>/dev/null; then
                        sudo "$@"
                else
                        printf '%s ' 'root'
                        su -c "$(printf '%q ' "$@")"
                fi
        else
                "$@"
        fi
}

summarize() {
        local -i filecount=$#
        local seenarch= seen= arch= name=
        local -r pkg_re='(.+)-[^-]+-[0-9]+-([^.]+)\.pkg.*'

        if (( delete )); then
                printf -v output 'finished: %d packages removed' "$filecount"
        elif (( move )); then
                printf -v output "finished: %d packages moved to \`%s'" "$filecount" "$movedir"
        elif (( dryrun )); then
                if (( verbose )); then
                        msg "Candidate packages:"
                        while read -r pkg; do
                                if (( verbose >= 3 )); then
                                        [[ $pkg =~ $pkg_re ]] && name=${BASH_REMATCH[1]} arch=${BASH_REMATCH[2]}
                                        if [[ -z $seen || $seenarch != $arch || $seen != $name ]]; then
                                                printf '%s (%s):\n' "$name" "$arch"
                                        fi
                                        printf '  %s\n' "$pkg"
                                elif (( verbose >= 2 )); then
                                        printf "$PWD/%s$delim" "$pkg"
                                else
                                        printf "%s$delim" "$pkg"
                                fi
                        done < <(printf '%s\n' "$@" | sort -V)
                        printf '\n' >&2
                fi

                printf -v output 'finished dry run: %d candidates' "$filecount"
        fi

  msg "$output (diskspace saved: %s)" "$(size_to_human "$totalsaved")"
}

usage() {
        cat <<EOF
usage: ${0##*/} <operation> [options] [targets...]

${0##*/} is a flexible pacman cache cleaning utility, which has numerous
options to help control how much, and what, is deleted from any directory
containing pacman package tarballs.

  Operations:
    -d               perform a dry run, only finding candidate packages.
    -m  <movedir>    move candidate packages to 'movedir'.
    -r               remove candidate packages.

  Options:
    -a  <arch>       scan for 'arch' (default: all architectures).
    -c  <cachedir>   scan 'cachedir' for packages (default: @localstatedir@/cache/pacman/pkg).
    -f               apply force to mv(1) and rm(1) operations.
    -h               display this help message.
    -i  <pkgs>       ignore 'pkgs', which is a comma separated. Alternatively,
                     specify '-' to read package names from stdin, newline delimited.
    -k  <num>        keep 'num' of each package in 'cachedir' (default: 3).
    -u               target uninstalled packages.
    -v               increase verbosity. specify up to 3 times.
    -z               use null delimiters for candidate names (only with -v and -vv)

EOF
}

if (( ! UID )); then
        error "Bad dog, no biscuit. You will be prompted for privilege escalation."
        exit 42
fi

while getopts ':a:c:dfhi:k:m:rsuvz' opt; do
        case $opt in
                a) scanarch=$OPTARG ;;
                c) cachedir=$OPTARG ;;
                d) dryrun=1 ;;
                f) cmdopts=(-f) ;;
                h) usage
                        exit 0 ;;
                i) if [[ $OPTARG = '-' ]]; then
                                 [[ ! -t 0 ]] && IFS=$'\n' read -r -d '' -a ign
                         else
                                 IFS=',' read -r -a ign <<< "$OPTARG"
                         fi
                         blacklist+=("${ign[@]}")
                        unset i ign ;;
                k) keep=$OPTARG
                        if [[ $keep != $OPTARG ]] || (( keep < 0 )); then
                                die 'argument to option -k must be a non-negative integer'
                        fi ;;
                m) move=1 movedir=$OPTARG ;;
                r) delete=1 ;;
                u) IFS=$'\n' read -r -d '' -a ign < <(pacman -Qq)
                         blacklist+=("${ign[@]}")
                         unset ign ;;
                v) (( ++verbose )) ;;
                z) delim='\0' ;;
                :) die "option '--%s' requires an argument" "$OPTARG" ;;
                ?) die "invalid option -- '%s'" "$OPTARG" ;;
        esac
done
shift $(( OPTIND - 1 ))

# remaining args are a whitelist
whitelist=("$@")

# sanity checks
case $(( dryrun+delete+move )) in
        0) die "no operation specified (use -h for help)" ;;
        [^1]) die "only one operation may be used at a time" ;;
esac

[[ -d $cachedir ]] ||
        die "cachedir \`%s' does not exist or is not a directory" "$cachedir"

[[ $movedir && ! -d $movedir ]] &&
        die "move-to directory \`%s' does not exist or is not a directory" "$movedir"

if (( move || delete )); then
        # make it an absolute path since we're about to chdir
        [[ ${movedir:0:1} != '/' ]] && movedir=$PWD/$movedir
        [[ ! -w $cachedir || ( $movedir && ! -w $movedir ) ]] && needsroot=1
fi

# unlikely that this will fail, but better make sure
cd "$cachedir" || die "failed to chdir to \`%s'" "$cachedir"

# note that these results are returned in an arbitrary order from awk, but
# they'll be resorted (in summarize) iff we have a verbosity level set.
IFS=$'\n' read -r -d '' -a candidates < \
        <(printf '%s\n' *.pkg.tar?(.+([^.])) | sort -V |
                pkgfilter "$keep" "$scanarch" \
                        "${#whitelist[*]}" "${whitelist[@]}" \
                        "${#blacklist[*]}" "${blacklist[@]}")

if (( ! ${#candidates[*]} )); then
        msg 'no candidate packages found for pruning'
        exit 1
fi

# do this before we destroy anything
totalsaved=$(@SIZECMD@ "${candidates[@]}" | awk '{ sum = $1 } END { print sum }')

# crush. kill. destroy.
(( verbose )) && cmdopts+=(-v)
if (( delete )); then
        runcmd rm "${cmdopts[@]}" "${candidates[@]}"
elif (( move )); then
        runcmd mv "${cmdopts[@]}" "${candidates[@]}" "$movedir"
fi

summarize "${candidates[@]}"