#! /bin/bash
# The functions used to mount and unmount the filesystems for lvmbuilder
#   lvmbuilder -- Debian package builder using LVM
#   Copyright (C) 2007 Kapil Hari Paranjape
#   based on:
#   pbuilder -- personal Debian package builder
#   Copyright (C) 2001-2006 Junichi Uekawa
#
#   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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA

# lvmbuilder by Kapil Hari Paranjape <kapil@debian.org> 2007 Aug 15
# pbuilder by Junichi Uekawa <dancer@debian.org> 2001 Aug 25

set -e 

function clean_basedev(){
    	echo -n "This will wipe out $BASEDEV. Proceed?[y/N]"
    	read ans
    	if [ "$ans" != "y" -a "$ans" != "Y" ] 
    	then
    		exit 0
	fi
    	echo "Making new file system at $BASEDEV."
	mke2fs $BASEDEV
}

function unmount_basedev(){
	umount $BASEDEV
	e2fsck -f -v $BASEDEV
}

function setup_workplace(){
	# Size computations
	BASESIZE=$(blockdev --getsize $BASEDEV)
	COWSIZE=$(blockdev --getsize $COWDEV)
	TOTAL=$[ $COWSIZE + $BASESIZE ]

	# Load the necessary modules
	modprobe dm_zero dm_mirror dm_snapshot dm_mod

	## Create the total base device
	# It consists of the base device extended by zeroes.
	# The length of the zeroes is the size of the cow.
	( echo 0 $BASESIZE linear $BASEDEV 0 ; \
	  echo $BASESIZE $COWSIZE zero ) | \
	  dmsetup create $TOTALNAME

	## Create the work device
	# It is the snapshot device with the all writes
	# going to the cow device. The file-system is resized
	# to the maximum extent possible.
	echo 0 $TOTAL snapshot $TOTALDEV $COWDEV n 16 | \
	  dmsetup create $WORKNAME

	[ -b $WORKDEV ] && resize2fs $WORKDEV
    	mount $WORKDEV $BUILDPLACE
}

function takedown_workplace(){
	umount /dev/mapper/lvmbuilder-work
	dmsetup remove lvmbuilder-work
	dmsetup remove lvmbuilder-total
}

function showhelp(){
    cat <<EOF
lvmbuilder - Debian package builder using pbuilder and lvm
Copyright 2007 Kapil Hari Paranjape
Based on:
pbuilder - a personal builder
Copyright 2001-2006 Junichi Uekawa
Distributed under GNU Public License version 2 or later

lvmbuilder [operation] [lvmbuilder-options]

command lines:
lvmbuilder create [--basedev base-device-path] [--distribution sarge|etch|sid|experimental]
  Creates a base distribution on an ext2 filesystem on the base block device 

lvmbuilder update [--basedev base-device-path] [--distribution sarge|etch|sid|experimental]
  Updates a base distribution on an ext2 filesystem on the base block device

lvmbuilder build [--basedev base-device-path] [--cowdev cow-device-path] pkgsrc.dsc
  Builds using the base distribution with all writes going to cow block device.
  Requires a .dsc filename

lvmbuilder clean [--basedev base-device-path]
  Creates a fresh ext2fs file system on the base block device.

lvmbuilder login
lvmbuilder execute -- [command] [command-options]
  Logs in to the build environment and execute command.

lvmbuilder dumpconfig
  Dumps configuration information to stdout for debugging.

lvmbuilder-options:
 --basedev [base device location]
 --cowdev [cow device location]
 --buildplace [location of build]
 --mirror [mirror location]
 --othermirror [other mirror location in apt deb-line format, delimited with | signs]
 --http-proxy [proxy]
 --distribution [distribution(sarge|sid|etch|experimental)]
 --buildresult [location-to-copy-build-result]
 --aptcache [location of retrieved package files]
 --removepackages [packages-to-remove on pbuilder create]
 --extrapackages [packages-to-add on pbuilder create]
 --configfile [configuration file to load]
 --debemail [mail address]
 --debbuildopts [dpkg-buildpackage options]
 --logfile [filename to output log]
 --pkgname-logfile
 --aptconfdir [overriding apt config dir]
 --timeout [timeout time]
 --override-config 
 --binary-arch
 --debug
 --autocleanaptcache
 --debootstrapopts [debootstrap options]
 --debootstrap [debootstrap|cdebootstrap]

EOF
    exit 1
}