scripts/pacman-optimize.sh.in

   1 #!/bin/bash
   2 #
   3 #   pacman-optimize
   4 #   @configure_input@
   5 #
   6 #   Copyright (c) 2006-2010 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'
  25 export TEXTDOMAINDIR='@localedir@'
  26
  27 myver='@PACKAGE_VERSION@'
  28 dbroot='@localstatedir@/lib/pacman/'
  29
  30 msg() {
  31         local mesg=$1; shift
  32         printf "==> ${mesg}\n" "$@" >&2
  33 }
  34
  35 error () {
  36         local mesg=$1; shift
  37         printf "==> ERROR: ${mesg}\n" "$@" >&2
  38 }
  39
  40 usage() {
  41         printf "pacman-optimize (pacman) %s\n\n" "$myver"
  42         printf "$(gettext "Usage: %s [pacman_db_root]")\n\n" "$0"
  43         printf "$(gettext "\
  44 pacman-optimize is a little hack that should improve the performance\n\
  45 of pacman when reading/writing to its filesystem-based database.\n\n")"
  46         printf "$(gettext "\
  47 Because pacman uses many small files to keep track of packages,\n\
  48 there is a tendency for these files to become fragmented over time.\n\
  49 This script attempts to relocate these small files into one\n\
  50 continuous location on your hard drive. The result is that the hard\n\
  51 drive should be able to read them faster, since the hard drive head\n\
  52 does not have to move around the disk as much.\n")"
  53 }
  54
  55 version() {
  56         printf "pacman-optimize (pacman) %s\n" "$myver"
  57         printf "$(gettext "\
  58 Copyright (c) 2006-2010 Pacman Development Team <pacman-dev@archlinux.org>.\n\
  59 Copyright (C) 2002-2006 Judd Vinet <jvinet@zeroflux.org>.\n\n\
  60 This is free software; see the source for copying conditions.\n\
  61 There is NO WARRANTY, to the extent permitted by law.\n")"
  62 }
  63
  64 die() {
  65         error "$@"
  66         exit 1
  67 }
  68
  69 die_r() {
  70         rm -f "$lockfile"
  71         die "$@"
  72 }
  73
  74 # PROGRAM START
  75
  76 # determine whether we have gettext; make it a no-op if we do not
  77 if ! type gettext &>/dev/null; then
  78         gettext() {
  79                 echo "$@"
  80         }
  81 fi
  82
  83 if [[ $1 = "-h" || $1 = "--help" ]]; then
  84         usage
  85         exit 0
  86 fi
  87
  88 if [[ $1 = "-V" || $1 = "--version" ]]; then
  89         version
  90         exit 0
  91 fi
  92
  93 if [[ -n $1 ]]; then
  94         dbroot="$1"
  95 fi
  96
  97 # make sure diff is installed
  98 if ! type diff >/dev/null 2>&1; then
  99         die "$(gettext "diff tool was not found, please install diffutils.")"
 100 fi
 101
 102 if [[ ! -d $dbroot ]]; then
 103         die "$(gettext "%s does not exist or is not a directory.")" "$dbroot"
 104 fi
 105
 106 if [[ ! -w $dbroot ]]; then
 107         die "$(gettext "You must have correct permissions to optimize the database.")"
 108 fi
 109
 110 # strip any trailing slash from our dbroot
 111 dbroot="${dbroot%/}"
 112 # form the path to our lockfile location
 113 lockfile="${dbroot}/db.lck"
 114
 115 # make sure pacman isn't running
 116 if [[ -f $lockfile ]]; then
 117         die "$(gettext "Pacman lock file was found. Cannot run while pacman is running.")"
 118 fi
 119 # do not let pacman run while we do this
 120 touch "$lockfile"
 121
 122 workdir=$(mktemp -d /tmp/pacman-optimize.XXXXXXXXXX) ||
 123         die_r "$(gettext "ERROR: Can not create temp directory for database building.")\n" >&2
 124
 125 # step 1: sum the old db
 126 msg "$(gettext "MD5sum'ing the old database...")"
 127 find "$dbroot" -type f | sort | xargs md5sum > "$workdir/pacsums.old"
 128
 129 # step 2: tar it up
 130 msg "$(gettext "Tar'ing up %s...")" "$dbroot"
 131 cd "$dbroot"
 132 bsdtar -czf "$workdir/pacman-db.tar.gz" ./
 133 if (( $? )); then
 134         rm -rf "$workdir"
 135         die_r "$(gettext "Tar'ing up %s failed.")" "$dbroot"
 136 fi
 137
 138 # step 3: make and sum the new db side-by-side with the old
 139 msg "$(gettext "Making and MD5sum'ing the new database...")"
 140 mkdir "$dbroot.new"
 141 bsdtar -xpf "$workdir/pacman-db.tar.gz" -C "$dbroot.new"
 142 if (( $? )); then
 143        rm -rf "$workdir"
 144        die_r "$(gettext "Untar'ing %s failed.")" "$dbroot"
 145 fi
 146 # immediate sync following extraction should get it written continuously on HDD
 147 msg "$(gettext "Syncing database to disk...")"
 148 sync
 149 find "$dbroot.new" -type f | sort | \
 150                 xargs md5sum | sed 's#.new##' > "$workdir/pacsums.new"
 151
 152 # step 4: compare the sums
 153 msg "$(gettext "Checking integrity...")"
 154 diff "$workdir/pacsums.old" "$workdir/pacsums.new" >/dev/null 2>&1
 155 if (( $? )); then
 156         # failed
 157         # leave our pacman-optimize tmpdir for checking to see what doesn't match up
 158         rm -rf "$dbroot.new"
 159         die_r "$(gettext "Integrity check FAILED, reverting to old database.")"
 160 fi
 161
 162 # step 5: shuffle the newly extracted DB into the proper location
 163 msg "$(gettext "Rotating database into place...")"
 164
 165 fail=0
 166 mv "$dbroot" "$dbroot.old" || fail=1
 167 mv "$dbroot.new" "$dbroot" || fail=1
 168 chmod --reference="$dbroot.old" "$dbroot" || fail=1
 169 chown --reference="$dbroot.old" "$dbroot" || fail=1
 170 if (( fail )); then
 171         # failure with our directory shuffle
 172         die_r "$(gettext "New database substitution failed. Check for $dbroot,\n$dbroot.old, and $dbroot.new directories.")"
 173 fi
 174 rm -rf "$dbroot.old"
 175
 176 # remove the lock file and our working directory with sums and tarfile
 177 rm -f "$lockfile"
 178 rm -rf "$workdir"
 179
 180 echo
 181 msg "$(gettext "Finished. Your pacman database has been optimized.")"
 182 echo
 183
 184 exit 0
 185
 186 # vim: set ts=2 sw=2 noet: