#!/bin/bash -e
#
# debtakeover
#
# $Id: debtakeover 159 2004-05-09 09:34:46Z guillem $
#
#	Convert a new non-Debian distribution to Debian proper
#
# Copyright (C) 2003, 2004 Guillem Jover <guillem@debian.org>
#
# 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; version 2 of the License.
#
# 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.
#


#
# User modifiable variables
#

REMOVE_EXCLUDES="/etc/mtab /etc/fstab /etc/hostname /etc/hosts
        /etc/resolv.conf /etc/lilo.conf /etc/modules /etc/modules.conf
        /etc/passwd /etc/shadow /etc/group /etc/gshadow /etc/grub.conf
        /etc/ssh/ssh_host_* /etc/network/interfaces"

STD_EXCLUDES="/tmp /root /home /opt /dev /proc /sys"

WORKDIR=~

#
# Function definitions
#

logpipe()
{
  if [ "$VERBOSE" = "yes" ]; then
    tee -a $LOGFILE
  else
    cat >> $LOGFILE
  fi
}

log()
{
  echo -e "$@" | logpipe
}

msg()
{
  echo -e "$@" | tee -a $LOGFILE
}

warning()
{
  msg "warning: $@" >&2
}

error()
{
  code=$1
  shift
  msg "error: $@" >&2
  if [ $code != 0 ]; then
    exit $code
  fi
}

sigerror()
{
  echo "Unexpected error, please report it with full logs it to: "
  echo "  $BUGS_ADDRESS"
}

usage()
{
  cat <<-HERE
	usage: $PROGRAM [options]
	
	options:
	
	    --profile=string	Installation profile (default "$DEFAULT_PROFILE")
	    --suite=string	Debian suite (default "$DEFAULT_SUITE")
	    --mirror=url	Debian mirror (default "$DEFAULT_MIRROR")
	    --tarball=file	Debian base tarball
	    --debootstrap=path	Debootstrap compatible binary (default "$DEFAULT_DEBOOTSTRAP")
	    --force-purify	Force the purification (non-interactive)
	    --force-retakeover	Force taking over a Debian system
	    --verbose		Be more verbose
	    --version		Print program version
	    --help		Print this help
	
HERE
  exit 0
}

setup_shell()
{
  msg "Stage (Setting up the shell)"
  msg "-----"

  msg "-> Disable bash executable path hashing."
  set +h

  # Some old bash versions does not support SIGERR on errors from set -e
  if trap -p ERR >& /dev/null; then
    msg "-> Setting signal handler."
    trap sigerror ERR
  fi
}

check_needed()
{
  msg "Stage (Checking for needed components)"
  msg "-----"

  check_print() { msg -n "-> Checking for $@ ... "; }

  check_print "superuser privileges"
  if [ `id -u` = 0 ]; then
    msg "ok."
  else
    msg "failed."
    error 4 "You need superuser privileges to run this program."
  fi

  if [ -z "$TARBALL" ]; then
    local DEBOOTSTRAP_NEEDED="$DEBOOTSTRAP wget ar MAKEDEV"
    # MAKEDEV may be only on /dev
    local NEWPATH=$PATH:/dev
  else
    local NEWPATH=$PATH
  fi
  local DEBTAKEOVER_NEEDED="grep sed diff tar gzip bzip2"

  for bin in $DEBOOTSTRAP_NEEDED $DEBTAKEOVER_NEEDED; do
    check_print "$bin"
    if PATH=$NEWPATH which $bin >& /dev/null; then
      msg "found."
    else
      msg "missing."
      local CHECK_MISSING=yes
    fi
  done

  if [ "$CHECK_MISSING" = yes ]; then
    error 2 "Please install missing software and try again."
  fi

  if [ "$FORCE_PURIFY" != yes ]; then
    REPLY_CHECK="Yes I am"
    warning "Are you sure what are you going to do ? [$REPLY_CHECK]"
    read
    if [ "$REPLY" != "$REPLY_CHECK" ]; then
      error 20 "Ok, you are not sure. Leaving $DISTRO distro untouched."
    fi
  fi
}

distro_detect()
{
  msg "Stage (Detecting current Distro)"
  msg "-----"

  # Set default redhat style network conf dir.
  NETWORK_REDHAT_CONF_DIR=/etc/sysconfig/network-scripts

  if [ -e /etc/mandrake-release ]
  then
    DISTRO=mandrake
    NETWORK_TYPE=redhat
  elif [ -e /etc/fedora-release ]
  then
    DISTRO=fedora
    NETWORK_TYPE=redhat
  elif [ -e /etc/redhat-release ]
  then
    DISTRO=redhat
    NETWORK_TYPE=redhat
  elif [ -e /etc/SuSE-release ]
  then
    DISTRO=suse
    NETWORK_TYPE=redhat
    # SuSE version < 8.0 used /etc/rc.config
    NETWORK_REDHAT_CONF_DIR=/etc/sysconfig/network
  elif [ -e /etc/slackware-version ]
  then
    DISTRO=slackware
  elif [ -e /etc/gentoo-release ]
  then
    DISTRO=gentoo
  elif [ -e /etc/cobalt-release ]
  then
    DISTRO=cobalt
  elif [ -e /etc/yellowdog-release ]
  then
    DISTRO=yellowdog
  elif [ -e /etc/turbolinux-release ]
  then
    DISTRO=turbolinux
  fi

  if [ -e /etc/debian_version ]
  then
    if [ "$DISTRO" = unknown ]; then
      if [ "$FORCE_RETAKEOVER" = yes ]; then
        DISTRO=debian
        NETWORK_TYPE=debian
        warning "Taking over a Debian system"
      else
        error 1 "You already have a Debian system"
      fi
    else
      warning "You have a mixed system, trying to continue"
      DISTRO_MIXED=yes
    fi
  fi

  msg $DISTRO
}

generic_exclusion_list()
{
  msg "Stage (Building the generic exclusion list)"
  msg "-----"

  msg "-> Generating exclusion file list"
  echo ${REMOVE_EXCLUDES} ${STD_EXCLUDES} ${DISTRO_EXCLUDES} \
    | xargs -n1 > $WORKDIR/debianize-exclude.list
  sed -e 's:^/::' $WORKDIR/debianize-exclude.list > $WORKDIR/debianize-tar-exclude.list
  STD_FIND_EXCLUDES=`for e in $STD_EXCLUDES; do echo "-path $e -prune -o "; done`
}

debian_tarball_build()
{
  msg "Stage (Building the base-tarball)"
  msg "-----"

  msg "-> Debootstrapping"
  $DEBOOTSTRAP --include="$DEBOOTSTRAP_INCLUDES" \
    --exclude="$DEBOOTSTRAP_EXCLUDES" \
        $DEBIAN_VERSION $DEBIAN_DIR $DEBIAN_MIRROR/debian 2>&1 | logpipe

  msg "-> Checking chroot sanity"
  for d in $DEBOOTSTRAP_CHECK_DIRS; do
    [ -d $DEBIAN_DIR$d ] || error 2 "Bad chroot, clean, correct, and try again."
  done

  msg "-> Removing unneeded files"
  rm -f $DEBIAN_DIR/var/lib/apt/lists/*_{Sources,Packages,Release}
  rm -f $DEBIAN_DIR/var/cache/apt/{*.bin,archives/*.deb}
  rm -rf $DEBIAN_DIR/dev

  msg "-> Setting up APT sources.list"
  cat > $DEBIAN_DIR/etc/apt/sources.list <<-EOF
	deb $DEBIAN_MIRROR_SECURITY/debian-security $DEBIAN_VERSION/updates main
	deb $DEBIAN_MIRROR/debian $DEBIAN_VERSION main
	deb $DEBIAN_MIRROR/debian-non-US $DEBIAN_VERSION/non-US main

	deb-src $DEBIAN_MIRROR_SECURITY/debian-security $DEBIAN_VERSION/updates main
	deb-src $DEBIAN_MIRROR/debian $DEBIAN_VERSION main
	deb-src $DEBIAN_MIRROR/debian-non-US $DEBIAN_VERSION/non-US main
EOF

  msg "-> Generating Debian files list"
  chroot $DEBIAN_DIR find / $STD_FIND_EXCLUDES -print \
    | sort > $WORKDIR/debianize-debian.list

  msg "-> Packaging Debian chroot"
  ( cd $DEBIAN_DIR; \
    tar cf $DEBIAN_TARBALL $DEBIAN_TARBALL_COMPRESSOR * )

  msg "-> Cleaning Debian chroot"
  rm -rf $DEBIAN_DIR
}

debian_tarball_prebuilt()
{
  msg "Stage (Setting up pre-built base-tarball)"
  msg "-----"

  msg "-> Generating Debian files list from pre-built tarball"
  tar tf $DEBIAN_TARBALL $DEBIAN_TARBALL_COMPRESSOR \
    | sort | sed -e 's,^,/,' > $WORKDIR/debianize-debian.list
}

distro_remove_list()
{
  msg "Stage (Building the remove list)"
  msg "-----"

  msg "-> Generating $DISTRO distro files list"
  find / \
    $STD_FIND_EXCLUDES \
       -path '/boot' -prune \
    -o -path '/var/run' -prune \
    -o -path '/var/log' -prune \
    -o -path '/var/local' -prune \
    -o -path '/usr/local' -prune \
    -o -path '/usr/src' -prune \
    -o -path '/lib/modules' -prune \
    -o -print | sort > $WORKDIR/debianize-$DISTRO.list

  msg "-> Generating $DISTRO distro files removal list"
  diff -u $WORKDIR/debianize-$DISTRO.list $WORKDIR/debianize-debian.list \
    | tail +2 | grep '^-' | sed -e 's,^-,,' \
    | grep -vxf $WORKDIR/debianize-exclude.list > $WORKDIR/debianize-remove.list
}

setup_network_debian()
{
  msg "-> Keeping Debian network config" >&2
}

setup_network_redhat()
{
  if [ -f /etc/sysconfig/network ]; then
    . /etc/sysconfig/network
  fi

  for f in $NETWORK_REDHAT_CONF_DIR/ifcfg-*; do
    unset DEVICE BROADCAST BOOTPROTO IPADDR NETMASK NETWORK ONBOOT || true

    . $f

    [ "$ONBOOT" = yes -o "$STARTMODE" = onboot ] && echo "auto $DEVICE"
    if [ "$DEVICE" = lo -o "$NAME" = loopback ]; then
      NET_METHOD=loopback
    elif [ -z "$BOOTPROTO" -o "$BOOTPROTO" = static -o "$BOOTPROTO" = none ]; then
      NET_METHOD=static
    else
      NET_METHOD=$BOOTPROTO
    fi
    echo "iface $DEVICE inet $NET_METHOD"
    if [ "$NET_METHOD" = static ]; then
      [ -n "$IPADDR" ] && echo "  address $IPADDR"
      [ -n "$BROADCAST" ] && echo "  broadcast $BROADCAST"
      [ -n "$NETMASK" ] && echo "  netmask $NETMASK"
      [ -n "$NETWORK" ] && echo "  network $NETWORK"
      [ -n "$GATEWAY" ] && echo "  gateway $GATEWAY"
    fi
    echo
  done
}

setup_network_gentoo()
{
  cat /etc/conf.d/net | grep -v '^ *#' | while read line
  do
    :
  done
}

setup_network_bsd()
{
  # /etc/rc.d/rc.inet1
  :
}

setup_network_none()
{
  warning "Distro $DISTRO does not have yet a network conversion scripts."
}

debian_preconfigure()
{
  msg "Stage (PreConfiguring)"
  msg "-----"

  msg "-> Preserving $DISTRO distro network configuration"
  mkdir -p /etc/network
  setup_network_${NETWORK_TYPE} > /etc/network/interfaces
  if [ ! -f /etc/hostname ]; then
    hostname -s > /etc/hostname
  fi

  msg "-> Preserving $DISTRO distro module configuration"
  mkdir -p /etc/modutils
  if [ -f /etc/conf.modules ]; then
    cat /etc/conf.modules >> /etc/modutils/$DISTRO
  fi
  if [ -f /etc/modules.conf ] &&
       ! grep update-modules /etc/modules.conf &> /dev/null; then
    cat /etc/modules.conf >> /etc/modutils/$DISTRO
  fi
}

debian_configure()
{
  msg "Stage (Configuring)"
  msg "-----"

  msg "-> Sanitizing user databases"
  update-passwd

  if [ ! -e /dev/.devfsd ]; then
    msg "-> Updating device nodes"
    cd /dev
    ln -sf /sbin/MAKEDEV
    ./MAKEDEV update || true
    cd -
  fi

  msg "-> Disabling unneeded network services"
  update-inetd --multi --disable discard,daytime,time

  if [ "$DEBTAKEOVER_PROFILE" = colo  ]; then
    msg "-> Setting up specific colo configurations"
    # TODO: Add a kernel paramater "panic=30"

    if [ -f /etc/default/rcS ]; then
      sed -e 's/^FSCKFIX=no/FSCKFIX=yes/;s/^TMPTIME=0/TMPTIME=15/' \
        < /etc/default/rcS > /tmp/rcS && mv -f /tmp/rcS /etc/default/
    fi

    msg "-> Converting halt to behave as reboot"
    rm -f /etc/rc0.d/S??halt
    cp -fd /etc/rc6.d/S??reboot /etc/rc0.d
  fi

  msg "-> Setting up module configurations"
  if [ ! -f /etc/modules ]; then
    > /etc/modules
  fi
  update-modules force

  msg "-> Setting up remaining configurations"
  dpkg --configure -a

  if ! grep '# Begin:.*debtakeover' ~/.bash_profile &> /dev/null; then
    msg "-> Sanitizing root PATH environment variable"
    cat >> ~/.bash_profile <<-EOF
	# Begin: automatically added by debtakeover
	PATH=/sbin:/usr/sbin:/usr/local/sbin:\$PATH
	# End
EOF
  fi
}

debian_dump()
{
  msg "Stage (Dump the tarball)"
  msg "-----"

  cd /

  msg "-> Making backups of important data"
  tar czvf $WORKDIR/$DISTRO-etc.tgz /etc 2>&1 | logpipe
  tar czvf $WORKDIR/$DISTRO-log.tgz /var/log 2>&1 | logpipe

  msg "-> Removing symlinks to directories"
  find / $STD_FIND_EXCLUDES -type l -xtype d -print | xargs rm -f || true

  msg "-> Dumping Debian over $DISTRO distro"
  tar xvf $DEBIAN_TARBALL $DEBIAN_TARBALL_COMPRESSOR --numeric-owner \
    -p -U -X $WORKDIR/debianize-tar-exclude.list 2>&1 | logpipe || true

  msg "-> Regenerating linker configuration"
  ldconfig
}

distro_trash()
{
  msg "Stage (Trash the old system)"
  msg "-----"

  msg "-> Removing remaining $DISTRO distro files"
  cat $WORKDIR/debianize-remove.list | xargs rm -f 2> /dev/null \
    | ( ldconfig; logpipe ) || true

  msg "-> Regenerating linker configuration"
  ldconfig

  msg "-> Removing remaining $DISTRO distro directories"
  cat $WORKDIR/debianize-remove.list | sort -r | xargs rmdir 2> /dev/null \
    | ( ldconfig; logpipe ) || true
}


#
# Main program
#

export LC_ALL=C

PROGRAM=debtakeover
VERSION=0.8
BUGS_ADDRESS="Guillem Jover <guillem@debian.org>"

DEFAULT_MIRROR=http://ftp.no.debian.org
DEFAULT_MIRROR_SECURITY=http://security.debian.org
DEFAULT_SUITE=woody
DEFAULT_PROFILE=colo
DEFAULT_DEBOOTSTRAP=debootstrap

# Process command line arguments

for arg do
  arg_value=`echo $arg | sed 's/--[^= ]*=//'`
  if echo $arg | grep -- '--[^= ]*=' >& /dev/null && [ -z "$arg_value" ]; then
    error 8 "Missing option value for '$arg'."
  fi
  case $arg in
    --verbose)
      VERBOSE=yes
      ;;
    --profile=*)
      PROFILE=$arg_value
      ;;
    --mirror=*)
      MIRROR=$arg_value
      ;;
    --suite=*)
      SUITE=$arg_value
      ;;
    --tarball=*)
      TARBALL=$arg_value
      local TARBALL_DIR=`dirname $TARBALL`
      if [ ${TARBALL_DIR:0:1} = / ]; then
	TARBALL=`pwd`/$TARBALL
      fi
      if [ ! -e $TARBALL ]; then
	error 11 "Tarball does not exist."
      fi
      case $TARBALL in
	*.tar.gz|*.tgz)
	  TARBALL_COMPRESSOR=--gzip
	;;
	*.tar.bz2)
	  TARBALL_COMPRESSOR=--bzip2
	;;
	*.tar.Z|*.taz)
	  TARBALL_COMPRESSOR=--compress
	;;
	*)
	  error 10 "Tarball extension not recognized."
	;;
      esac
      ;;
    --debootstrap=*)
      USER_DEBOOTSTRAP=$arg_value
      ;;
    --force-purify)
      FORCE_PURIFY=yes
      ;;
    --force-retakeover)
      FORCE_RETAKEOVER=yes
      ;;
    --version)
      echo "$PROGRAM $VERSION"
      exit 0
      ;;
    --help)
      usage
      ;;
    *)
      error 0 "Unrecognized '$arg' option or value for option not specified."
      usage
      ;;
  esac
  shift
done

# Initialize some variables

LOGFILE=$WORKDIR/$PROGRAM.log

DISTRO=unknown
DISTRO_MIXED=no
NETWORK_TYPE=none

DEBIAN_MIRROR=${MIRROR:-$DEFAULT_MIRROR}
DEBIAN_MIRROR_SECURITY=${MIRROR_SECURITY:-$DEFAULT_MIRROR_SECURITY}
DEBIAN_VERSION=${SUITE:-$DEFAULT_SUITE}
DEBIAN_TARBALL=${TARBALL:-$WORKDIR/debian-$DEBIAN_VERSION.tar.bz2}
DEBIAN_TARBALL_COMPRESSOR=${TARBALL_COMPRESSOR:---bzip2}
DEBIAN_DIR=debian-$DEBIAN_VERSION-chroot

DEBTAKEOVER_PROFILE=${PROFILE:-$DEFAULT_PROFILE}

DEBOOTSTRAP=${USER_DEBOOTSTRAP:-$DEFAULT_DEBOOTSTRAP}
DEBOOTSTRAP_CHECK_DIRS="/etc/apt /bin /sbin /dev /var/lib/dpkg/info \
	/var/lib/apt/lists /var/cache/apt"
DEBOOTSTRAP_INCLUDES="ssh,grub,libssl0.9.6,zlib1g"
if [ "$DEBTAKEOVER_PROFILE" = "colo"  ]; then
  DEBOOTSTRAP_EXCLUDES="setserial,fdutils,ipchains,pcmcia-cs,ppp,pppconfig,\
pppoe,pppoeconf"
else
  DEBOOTSTRAP_EXCLUDES=""
fi

# Impure non-Debian system

log "-> $PROGRAM started on `date -Iseconds | tr 'T' ' '`"
msg "-> Running $PROGRAM $VERSION"

setup_shell

distro_detect
check_needed

if [ "$DISTRO_MIXED" = no ]; then
  generic_exclusion_list
  if [ "$TARBALL" ]; then
    debian_tarball_prebuilt
  else
    debian_tarball_build
  fi
  distro_remove_list
  debian_dump
fi

# Mixed system

debian_preconfigure
distro_trash

# Pure Debian system

debian_configure

msg "Congratulations, you have now a Debian $DEBIAN_VERSION system !"
log "-> $PROGRAM finished on `date -Iseconds | tr 'T' ' '`"

exit 0