scripts/pacman-optimize.sh.in

   1 #!@BASH_SHELL@
   2 #
   3 #   pacman-optimize
   4 #   @configure_input@
   5 #
   6 #   Copyright (c) 2006-2011 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
  29 eval $(awk '/DBPath/ {print $1$2$3}' @sysconfdir@/pacman.conf)
  30 dbroot="${DBPath:-@localstatedir@/lib/pacman/}"
  31
  32 msg() {
  33         local mesg=$1; shift
  34         printf "==> ${mesg}\n" "$@" >&2
  35 }
  36
  37 error () {
  38         local mesg=$1; shift
  39         printf "==> ERROR: ${mesg}\n" "$@" >&2
  40 }
  41
  42 usage() {
  43         printf "pacman-optimize (pacman) %s\n\n" "$myver"
  44         printf "$(gettext "Usage: %s [pacman_db_root]")\n\n" "$0"
  45         printf "$(gettext "\
  46 pacman-optimize is a little hack that should improve the performance\n\
  47 of pacman when reading/writing to its filesystem-based database.\n\n")"
  48         printf "$(gettext "\
  49 Because pacman uses many small files to keep track of packages,\n\
  50 there is a tendency for these files to become fragmented over time.\n\
  51 This script attempts to relocate these small files into one\n\
  52 continuous location on your hard drive. The result is that the hard\n\
  53 drive should be able to read them faster, since the hard drive head\n\
  54 does not have to move around the disk as much.\n")"
  55 }
  56
  57 version() {
  58         printf "pacman-optimize (pacman) %s\n" "$myver"
  59         printf "$(gettext "\
  60 Copyright (c) 2006-2011 Pacman Development Team <pacman-dev@archlinux.org>.\n\
  61 Copyright (C) 2002-2006 Judd Vinet <jvinet@zeroflux.org>.\n\n\
  62 This is free software; see the source for copying conditions.\n\
  63 There is NO WARRANTY, to the extent permitted by law.\n")"
  64 }
  65
  66 die() {
  67         error "$@"
  68         exit 1
  69 }
  70
  71 die_r() {
  72         rm -f "$lockfile"
  73         die "$@"
  74 }
  75
  76 # PROGRAM START
  77
  78 # determine whether we have gettext; make it a no-op if we do not
  79 if ! type gettext &>/dev/null; then
  80         gettext() {
  81                 echo "$@"
  82         }
  83 fi
  84
  85 if [[ $1 = "-h" || $1 = "--help" ]]; then
  86         usage
  87         exit 0
  88 fi
  89
  90 if [[ $1 = "-V" || $1 = "--version" ]]; then
  91         version
  92         exit 0
  93 fi
  94
  95 if [[ -n $1 ]]; then
  96         dbroot="$1"
  97 fi
  98
  99 # make sure diff is installed
 100 if ! type diff >/dev/null 2>&1; then
 101         die "$(gettext "diff tool was not found, please install diffutils.")"
 102 fi
 103
 104 if [[ ! -d $dbroot || ! -d $dbroot/local ]]; then
 105         die "$(gettext "%s does not exist or is not a directory.")" "$dbroot"
 106 fi
 107
 108 if [[ ! -w $dbroot ]]; then
 109         die "$(gettext "You must have correct permissions to optimize the database.")"
 110 fi
 111
 112 # strip any trailing slash from our dbroot
 113 dbroot="${dbroot%/}"
 114 # form the path to our lockfile location
 115 lockfile="${dbroot}/db.lck"
 116
 117 # make sure pacman isn't running
 118 if [[ -f $lockfile ]]; then
 119         die "$(gettext "Pacman lock file was found. Cannot run while pacman is running.")"
 120 fi
 121 # do not let pacman run while we do this
 122 touch "$lockfile"
 123
 124 workdir=$(mktemp -d /tmp/pacman-optimize.XXXXXXXXXX) ||
 125         die_r "$(gettext "ERROR: Can not create temp directory for database building.")\n" >&2
 126
 127 # step 1: sum the old db
 128 msg "$(gettext "MD5sum'ing the old database...")"
 129 find "$dbroot" -type f | sort | xargs md5sum > "$workdir/pacsums.old"
 130
 131 # step 2: tar it up
 132 msg "$(gettext "Tar'ing up %s...")" "$dbroot"
 133 cd "$dbroot"
 134 bsdtar -czf "$workdir/pacman-db.tar.gz" ./
 135 if (( $? )); then
 136         rm -rf "$workdir"
 137         die_r "$(gettext "Tar'ing up %s failed.")" "$dbroot"
 138 fi
 139
 140 # step 3: make and sum the new db side-by-side with the old
 141 msg "$(gettext "Making and MD5sum'ing the new database...")"
 142 mkdir "$dbroot.new"
 143 bsdtar -xpf "$workdir/pacman-db.tar.gz" -C "$dbroot.new"
 144 if (( $? )); then
 145        rm -rf "$workdir"
 146        die_r "$(gettext "Untar'ing %s failed.")" "$dbroot"
 147 fi
 148 # immediate sync following extraction should get it written continuously on HDD
 149 msg "$(gettext "Syncing database to disk...")"
 150 sync
 151 find "$dbroot.new" -type f | sort | \
 152                 xargs md5sum | sed 's#.new##' > "$workdir/pacsums.new"
 153
 154 # step 4: compare the sums
 155 msg "$(gettext "Checking integrity...")"
 156 diff "$workdir/pacsums.old" "$workdir/pacsums.new" >/dev/null 2>&1
 157 if (( $? )); then
 158         # failed
 159         # leave our pacman-optimize tmpdir for checking to see what doesn't match up
 160         rm -rf "$dbroot.new"
 161         die_r "$(gettext "Integrity check FAILED, reverting to old database.")"
 162 fi
 163
 164 # step 5: shuffle the newly extracted DB into the proper location
 165 msg "$(gettext "Rotating database into place...")"
 166
 167 fail=0
 168 mv "$dbroot" "$dbroot.old" || fail=1
 169 mv "$dbroot.new" "$dbroot" || fail=1
 170 chmod --reference="$dbroot.old" "$dbroot" || fail=1
 171 chown --reference="$dbroot.old" "$dbroot" || fail=1
 172 if (( fail )); then
 173         # failure with our directory shuffle
 174         die_r "$(gettext "New database substitution failed. Check for $dbroot,\n$dbroot.old, and $dbroot.new directories.")"
 175 fi
 176 rm -rf "$dbroot.old"
 177
 178 # remove the lock file and our working directory with sums and tarfile
 179 rm -f "$lockfile"
 180 rm -rf "$workdir"
 181
 182 echo
 183 msg "$(gettext "Finished. Your pacman database has been optimized.")"
 184 echo
 185
 186 exit 0
 187
 188 # vim: set ts=2 sw=2 noet: