scripts/pacman-optimize.sh.in

   1 #!/bin/bash
   2 #
   3 #   pacman-optimize
   4 #   @configure_input@
   5 #
   6 #   Copyright (c) 2006-2012 Pacman Development Team <pacman-dev@archlinux.org>
   7 #   Copyright (c) 2002-2006 by Judd Vinet <jvinet@zeroflux.org>
   8 #
   9 #   This program is free software; you can redistribute it and/or modify
  10 #   it under the terms of the GNU General Public License as published by
  11 #   the Free Software Foundation; either version 2 of the License, or
  12 #   (at your option) any later version.
  13 #
  14 #   This program is distributed in the hope that it will be useful,
  15 #   but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 #   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 #   GNU General Public License for more details.
  18 #
  19 #   You should have received a copy of the GNU General Public License
  20 #   along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 #
  22
  23 # gettext initialization
  24 export TEXTDOMAIN='pacman-scripts'
  25 export TEXTDOMAINDIR='@localedir@'
  26
  27 declare -r myver='@PACKAGE_VERSION@'
  28
  29 eval $(awk '/DBPath/ {print $1$2$3}' @sysconfdir@/pacman.conf)
  30 dbroot="${DBPath:-@localstatedir@/lib/pacman/}"
  31
  32 m4_include(library/output_format.sh)
  33
  34 usage() {
  35         printf "pacman-optimize (pacman) %s\n\n" "$myver"
  36         printf -- "$(gettext "Usage: %s [pacman_db_root]")\n\n" "$0"
  37         printf -- "$(gettext "\
  38 pacman-optimize is a little hack that should improve the performance\n\
  39 of pacman when reading/writing to its filesystem-based database.\n\n")"
  40         printf -- "$(gettext "\
  41 Because pacman uses many small files to keep track of packages,\n\
  42 there is a tendency for these files to become fragmented over time.\n\
  43 This script attempts to relocate these small files into one\n\
  44 continuous location on your hard drive. The result is that the hard\n\
  45 drive should be able to read them faster, since the hard drive head\n\
  46 does not have to move around the disk as much.\n")"
  47 }
  48
  49 version() {
  50         printf "pacman-optimize (pacman) %s\n" "$myver"
  51         printf -- "$(gettext "\
  52 Copyright (c) 2006-2012 Pacman Development Team <pacman-dev@archlinux.org>.\n\
  53 Copyright (C) 2002-2006 Judd Vinet <jvinet@zeroflux.org>.\n\n\
  54 This is free software; see the source for copying conditions.\n\
  55 There is NO WARRANTY, to the extent permitted by law.\n")"
  56 }
  57
  58 die() {
  59         error "$@"
  60         exit 1
  61 }
  62
  63 die_r() {
  64         rm -f "$lockfile"
  65         die "$@"
  66 }
  67
  68 # PROGRAM START
  69
  70 # determine whether we have gettext; make it a no-op if we do not
  71 if ! type gettext &>/dev/null; then
  72         gettext() {
  73                 echo "$@"
  74         }
  75 fi
  76
  77 if [[ $1 = "-h" || $1 = "--help" ]]; then
  78         usage
  79         exit 0
  80 fi
  81
  82 if [[ $1 = "-V" || $1 = "--version" ]]; then
  83         version
  84         exit 0
  85 fi
  86
  87 if [[ -n $1 ]]; then
  88         dbroot="$1"
  89 fi
  90
  91 if ! type -p openssl >/dev/null; then
  92         die "$(gettext "Cannot find the %s binary required for verifying integrity.")" "openssl"
  93 fi
  94
  95 if [[ ! -d $dbroot || ! -d $dbroot/local ]]; then
  96         die "$(gettext "%s does not exist or is not a directory.")" "$dbroot"
  97 fi
  98
  99 if [[ ! -w $dbroot ]]; then
 100         die "$(gettext "You must have correct permissions to optimize the database.")"
 101 fi
 102
 103 # strip any trailing slash from our dbroot
 104 dbroot="${dbroot%/}"
 105 lockfile="${dbroot}/db.lck"
 106 localdb="${dbroot}/local"
 107
 108 # make sure pacman isn't running
 109 if [[ -f $lockfile ]]; then
 110         die "$(gettext "Pacman lock file was found. Cannot run while pacman is running.")"
 111 fi
 112 # do not let pacman run while we do this
 113 touch "$lockfile"
 114
 115 workdir=$(mktemp -d "${TMPDIR:-/tmp}/pacman-optimize.XXXXXXXXXX") ||
 116         die_r "$(gettext "Can not create temp directory for database building.")\n" >&2
 117
 118 # step 1: sum the old db
 119 msg "$(gettext "MD5sum'ing the old database...")"
 120 (cd "$localdb" && find . -type f -print0 | \
 121         xargs -0 openssl dgst -md5 | sort > "$workdir/pacsums.old")
 122
 123 # step 2: tar it up
 124 msg "$(gettext "Tar'ing up %s...")" "$localdb"
 125 bsdtar -czf "$workdir/pacman-db.tar.gz" -C "$localdb" ./
 126 if (( $? )); then
 127         rm -rf "$workdir"
 128         die_r "$(gettext "Tar'ing up %s failed.")" "$localdb"
 129 fi
 130
 131 # step 3: make and sum the new db side-by-side with the old
 132 msg "$(gettext "Making and MD5sum'ing the new database...")"
 133 mkdir "$localdb.new"
 134 bsdtar -xpf "$workdir/pacman-db.tar.gz" -C "$localdb.new"
 135 if (( $? )); then
 136        rm -rf "$workdir"
 137        die_r "$(gettext "Untar'ing %s failed.")" "$localdb"
 138 fi
 139 # immediate sync following extraction should get it written continuously on HDD
 140 msg "$(gettext "Syncing database to disk...")"
 141 sync
 142 (cd "$localdb.new" && find . -type f -print0 | \
 143         xargs -0 openssl dgst -md5 | sort > "$workdir/pacsums.new")
 144
 145 # step 4: compare the sums
 146 msg "$(gettext "Checking integrity...")"
 147 read -ra old_dgst < <(openssl dgst -md5 < "$workdir/pacsums.old")
 148 read -ra new_dgst < <(openssl dgst -md5 < "$workdir/pacsums.new")
 149 if [[ ${old_dgst[@]:(-1)} != ${new_dgst[@]:(-1)} ]]; then
 150         # failed
 151         # leave our pacman-optimize tmpdir for checking to see what doesn't match up
 152         rm -rf "$localdb.new"
 153         die_r "$(gettext "Integrity check FAILED, reverting to old database.")"
 154 fi
 155
 156 # step 5: shuffle the newly extracted DB into the proper location
 157 msg "$(gettext "Rotating database into place...")"
 158
 159 fail=0
 160 mv "$localdb" "$localdb.old" || fail=1
 161 mv "$localdb.new" "$localdb" || fail=1
 162 chmod --reference="$localdb.old" "$localdb" || fail=1
 163 chown --reference="$localdb.old" "$localdb" || fail=1
 164 if (( fail )); then
 165         # failure with our directory shuffle
 166         die_r "$(gettext "New database substitution failed. Check for %s, %s, and %s directories.")" "$localdb" "$localdb.old" "$localdb.new"
 167 fi
 168 rm -rf "$localdb.old"
 169
 170 # remove the lock file and our working directory with sums and tarfile
 171 rm -f "$lockfile"
 172 rm -rf "$workdir"
 173
 174 echo
 175 msg "$(gettext "Finished. Your pacman database has been optimized.")"
 176 echo
 177
 178 exit 0
 179
 180 # vim: set ts=2 sw=2 noet: