scripts/pacman-optimize.sh.in

   1 #!/bin/bash
   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-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 "$(gettext "\
  52 Copyright (c) 2006-2011 Pacman Development Team <pacman-dev@archlinux.org>.\n\
  53 Copyright (C) 2002-2006 Judd Vinet <jvinet@zeroflux.org>.\n\n\
  54 This is free software; see the source for copying conditions.\n\
  55 There is NO WARRANTY, to the extent permitted by law.\n")"
  56 }
  57
  58 die() {
  59         error "$@"
  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="$1"
  89 fi
  90
  91 # make sure diff is installed
  92 if ! type diff >/dev/null 2>&1; then
  93         die "$(gettext "diff tool was not found, please install diffutils.")"
  94 fi
  95
  96 if [[ ! -d $dbroot || ! -d $dbroot/local ]]; then
  97         die "$(gettext "%s does not exist or is not a directory.")" "$dbroot"
  98 fi
  99
 100 if [[ ! -w $dbroot ]]; then
 101         die "$(gettext "You must have correct permissions to optimize the database.")"
 102 fi
 103
 104 # strip any trailing slash from our dbroot
 105 dbroot="${dbroot%/}"
 106 # form the path to our lockfile location
 107 lockfile="${dbroot}/db.lck"
 108
 109 # make sure pacman isn't running
 110 if [[ -f $lockfile ]]; then
 111         die "$(gettext "Pacman lock file was found. Cannot run while pacman is running.")"
 112 fi
 113 # do not let pacman run while we do this
 114 touch "$lockfile"
 115
 116 workdir=$(mktemp -d "${TMPDIR:-/tmp}/pacman-optimize.XXXXXXXXXX") ||
 117         die_r "$(gettext "Can not create temp directory for database building.")\n" >&2
 118
 119 # step 1: sum the old db
 120 msg "$(gettext "MD5sum'ing the old database...")"
 121 find "$dbroot" -type f | sort | xargs md5sum > "$workdir/pacsums.old"
 122
 123 # step 2: tar it up
 124 msg "$(gettext "Tar'ing up %s...")" "$dbroot"
 125 cd "$dbroot"
 126 bsdtar -czf "$workdir/pacman-db.tar.gz" ./
 127 if (( $? )); then
 128         rm -rf "$workdir"
 129         die_r "$(gettext "Tar'ing up %s failed.")" "$dbroot"
 130 fi
 131
 132 # step 3: make and sum the new db side-by-side with the old
 133 msg "$(gettext "Making and MD5sum'ing the new database...")"
 134 mkdir "$dbroot.new"
 135 bsdtar -xpf "$workdir/pacman-db.tar.gz" -C "$dbroot.new"
 136 if (( $? )); then
 137        rm -rf "$workdir"
 138        die_r "$(gettext "Untar'ing %s failed.")" "$dbroot"
 139 fi
 140 # immediate sync following extraction should get it written continuously on HDD
 141 msg "$(gettext "Syncing database to disk...")"
 142 sync
 143 find "$dbroot.new" -type f | sort | \
 144                 xargs md5sum | sed 's#.new##' > "$workdir/pacsums.new"
 145
 146 # step 4: compare the sums
 147 msg "$(gettext "Checking integrity...")"
 148 diff "$workdir/pacsums.old" "$workdir/pacsums.new" >/dev/null 2>&1
 149 if (( $? )); then
 150         # failed
 151         # leave our pacman-optimize tmpdir for checking to see what doesn't match up
 152         rm -rf "$dbroot.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 "$dbroot" "$dbroot.old" || fail=1
 161 mv "$dbroot.new" "$dbroot" || fail=1
 162 chmod --reference="$dbroot.old" "$dbroot" || fail=1
 163 chown --reference="$dbroot.old" "$dbroot" || fail=1
 164 if (( fail )); then
 165         # failure with our directory shuffle
 166         die_r "$(gettext "New database substitution failed. Check for $dbroot,\n$dbroot.old, and $dbroot.new directories.")"
 167 fi
 168 rm -rf "$dbroot.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: