n0yd

#!/bin/bash 
# 
#   pacman-cage 
# 
#   Copyright (c) 2002-2006 by Dylan Harkleroad <d.harkleroad@gmail.com> 
#   I used Judd Vinet's pacman-optimise as a framework. 
# 
#   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, write to the Free Software 
#   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 
#   USA. 
# 

myver='2.9.8' 
dbroot="/var/lib/pacman" 
pacmandb="/var/lib/pacman.db" 

usage() { 
        echo "pacman-cage $myver" 
        echo "usage: $0 [pacman_db_root]" 
        echo 
        echo "pacman-cage creates a loopbacked filesystem in a contigious file." 
        echo "This will give better response times when using pacman" 
        echo 
} 

die() { 
        echo "pacman-cage: $*" >&2 
        exit 1 
} 

die_r() { 
        rm -f /tmp/pacman.lck 
        die $* 
} 

if [ "$1" != "" ]; then 
        if [ "$1" = "-h" -o "$1" = "--help" ]; then 
                usage 
                exit 0 
        fi 
        dbroot=$1 
fi 

if [ "`id -u`" != 0 ]; then 
        die "You must be root to cage the database" 
fi 

# make sure pacman isn't running 
if [ -f /tmp/pacman.lck ]; then 
        die "Pacman lockfile was found.  Cannot run while pacman is running." 
fi 
# make sure pacman.db hasnt already been made 
if [ -f $pacmandb ]; then 
        die "$pacmandb already exists!." 
fi 

if [ ! -d $dbroot ]; then 
        die "$dbroot does not exist or is not a directory" 
fi 

# don't let pacman run while we do this 
touch /tmp/pacman.lck 
  
# step 1: sum the old db 
echo "==> md5sum'ing the old database..." 
find $dbroot -type f | sort | xargs md5sum >/tmp/pacsums.old 

echo "==> creating pacman.db loopback file..." 
dd if=/dev/zero of=$pacmandb bs=1M count=150 > /dev/null 2>&1 

echo "==> creating ext2 -O dir_index -b 1024 -m 0 on $pacmandb..." 
yes | mkfs.ext2 -O dir_index -b 1024 -m 0 $pacmandb > /dev/null 2>&1 
        
echo "==> creating temporary mount point /mnt/tmp-pacman.." 
mkdir /mnt/tmp-pacman 

echo "==> mounting pacman.db to temporary mount point..." 
mount -o loop $pacmandb /mnt/tmp-pacman 

echo "==> copying pacman database to temporary mount point..." 
cp -a /var/lib/pacman/. /mnt/tmp-pacman 

echo "==> unmounting temporary mount point..." 
umount /mnt/tmp-pacman 

echo "==> removing temporary mount point..." 
rmdir /mnt/tmp-pacman 
        
echo "==> moving old /var/lib/pacman to /var/lib/pacman.bak..." 
mv /var/lib/pacman /var/lib/pacman.bak 
        
echo "==> createing new pacman db mount point @ $dbroot..." 
mkdir $dbroot 

echo "==> Mounting new pacman db..." 
mount -o loop $pacmandb $dbroot 

echo "==> md5sum'ing the new database..." 
find $dbroot -type f | sort | xargs md5sum >/tmp/pacsums.new 

echo "==> checking integrity..." 
diff /tmp/pacsums.old /tmp/pacsums.new >/dev/null 2>&1 
if [ $? -ne 0 ]; then 
        # failed, move the old one back into place 
        umount $dbroot 
        rm $pacmandb 
        mv $dbroot.bak $dbroot 
        die_r "integrity check FAILED, reverting to old database" 
fi 

echo "==> Updating /etc/fstab to reflect changes..." 
echo "$pacmandb $dbroot ext2 loop,defaults 0 0" >> /etc/fstab 
  
rm -f /tmp/pacman.lck /tmp/pacsums.old /tmp/pacsums.new 
  
echo 
echo "Finished.  Your pacman database has been caged!.  May the speedy pacman be with you." 
echo 

exit 0