#!/bin/sh

# $Id$

# Copyright  2014  Eric Hameleers, Eindhoven, NL
# 
# Permission to use, copy, modify, and/or distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
# 
# THE SOFTWARE IS PROVIDED ``AS IS'' AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

# ---------------------------------------------------------------------------

# Extract, test and manage doinst.sh scripts of compat32 packages.

# Catch errors and display the offending line number:
set -e
trap 'echo "$0 FAILED at line ${LINENO}"' ERR

# Package-independent variables
ARCH=${ARCH:-$(uname -m)}
TAG=${TAG:-compat32}      # tag to be used for the converted package
OUTPUT=${OUTPUT:-/tmp}    # where the package gets created
TMP=${TMP:-/tmp}          # location for temporary files

# $BUILD can also be overridden, though it in-turn is overridden
# if an output package name is specified on the command line.

# Blacklist of packages not to use this script on (these *have* to be compiled
# on a 64bit box):
BLACKLIST="
glibc.*
kernel.*
gcc.*
"

function show_help () {
  # Write the help text to output:
  cat <<EOF

Usage: $0 <-i input_package_file_name> [-d output_directory]

$(basename $0) is used to extract, test and manage the doinst.sh script
in  a 32-bit compatibility Slackware package.

required parameters::
  -i input_package_file_name     : 32-bit package to convert
optional parameters::
  -d destination_directory       : write doinst script in this directory

environment variables:
  ARCH   (target architecture; defaults to \$(uname -m))
  BUILD  (build number for output package; defaults to same as input package.
          output_package_file_name overrides this value)
  TAG    (build tag, defaults to ${TAG}))
  OUTPUT (location to create the package; defaults to ${OUTPUT})
  TMP    (location for temporary files; defaults to ${TMP})

EOF
}

# Zero some initial variables:
OUTPKG=""
PKGEXT="txz"
PKGFILE=""
PKGPATH=""
SLACKDESC=""

# Parse the commandline parameters:
while [ ! -z "$1" ]; do
  case $1 in
    -d|--destdir)
      OUTPUT="$(cd ${2}; pwd)"  # can be overruled in the "-o" argument!
      shift 2
      ;;
    -h|--help)
      show_help
      exit 0
      ;;
    -i|--inpkg)
      PKGFILE="$(basename ${2})"
      PKGPATH="$(cd $(dirname ${2}); pwd)/$(basename ${2})"
      shift 2
      ;;
    -*)
      echo "Unsupported parameter '$1'!"
      exit 1
      ;;
    *)
      # Do nothing
      shift
      ;;
  esac
done

# Bail out now if we did not get an input package:
if [ -z "$PKGFILE" -o ! -e "$PKGPATH" ]; then
  echo "** Please supply a valid input package! **"
  show_help
  exit 3
fi

# if a destination_directory was specified, abort now if we can not create it:
if [ -n "$OUTPUT" -a ! -d "$OUTPUT" ]; then
  echo "Creating output directory '$OUTPUT'..."
  mkdir -p $OUTPUT
  if [ ! -w "$OUTPUT" ]; then
    echo "Creating output directory '$OUTPUT' failed!"
    exit 3
  fi
fi

# Figure out initial variables
PKGNAM=$(echo $PKGFILE | rev | cut -f4- -d- | rev)
VERSION=$(echo $PKGFILE | rev | cut -f3 -d- | rev)
BUILD=${BUILD:-$(echo $PKGFILE | rev | cut -f1 -d- | cut -f2- -d. | rev)}
OUTPKG=${OUTPKG:-"${PKGNAM}-compat32-${VERSION}-${ARCH}-${BUILD}${TAG}.${PKGEXT}"}
# With OUTPKG as commandline param, it may not just be "${PKGNAM}-compat32":
PKGNAM32=$(echo $OUTPKG | rev | cut -f4- -d- | rev)

for regex in $BLACKLIST; do
  if echo $PKGNAM | grep -Pq "$regex"; then
    echo "Package $PKGNAM is blacklisted by '$regex', aborting."
    exit 2
  fi
done

echo "Extracting doinst.sh from package $PKGNAM (version $VERSION):"

PKG=$TMP/package-$PKGNAM32
rm -rf $PKG
mkdir -p $PKG $TMP
cd $PKG || exit 1

# Explode the package into $PKG .
# We will need to slightly modify an existing install/doinst.sh
# It should still create symlinks and run other errands when the resulting
# package is installed, but should not mess with the files we are going to
# remove for the -compat32 package.
/sbin/explodepkg $PKGPATH

# Check if the user fed us a 64bit package:
if [ -d usr/lib64 -o -d lib64 ]; then
  echo "** This script converts 32bit packages for Slackware64 multilib!"
  echo "** It looks like you gave me a 64bit package instead."
  echo "** Are you certain you want to convert the package $(basename $PKGPATH) ?"
  echo "** Press [Ctrl]-[C] now if you want to abort the script."
  read JUNK
fi

#
# Take special care of gtk+2, gdk-pixbuf2, pango and udev when stripping things!
#

# No doinst.sh ?
if [ ! -e install/doinst.sh ]; then
  touch $OUTPUT/$PKGNAM
  touch $OUTPUT/$PKGNAM32
  exit 0
else
  cat install/doinst.sh > $OUTPUT/$PKGNAM
fi

# Strip doinst.sh from everything we can't use:
if [ "$PKGNAM" = "gtk+2" -o "$PKGNAM" = "gdk-pixbuf2" -o "$PKGNAM" = "pango" ];
then
  # Get rid of symlinks in bin and doc directory:
  cat install/doinst.sh | grep -v '( cd usr/bin' | grep -v '( cd usr/doc' \
    > install/doinst.sh.2
  cat install/doinst.sh.2 > install/doinst.sh
  rm -f install/doinst.sh.2
  if [ "$PKGNAM" = "gtk+2" ]; then
    # Deal with the .new file in gtk+2 that does not get processed:
    echo "config etc/gtk-2.0/im-multipress.conf.new" \
      >> install/doinst.sh
  fi
elif [ "$PKGNAM" = "udev" ]; then
  # Get rid of symlinks in sbin and lib directory, and all the other 
  # non-symlinking stuff:
  cat install/doinst.sh \
    | grep '( cd ' \
    | grep -v '( cd sbin' | grep -v '( cd lib/udev' \
    | grep -v '( cd usr/lib/ConsoleKit/run-seat.d' \
     > install/doinst.sh.2
  cat install/doinst.sh.2 > install/doinst.sh
  rm -f install/doinst.sh.2
elif [ -f install/doinst.sh ]; then
  # Check for a 'config()' section:
  if grep -q 'config()' install/doinst.sh ; then
    cat <<-"EOT" > install/doinst.sh.1
	config() {
	  NEW="$1"
	  OLD="$(dirname $NEW)/$(basename $NEW .new)"
	  # If there's no config file by that name, mv it over:
	  if [ ! -r $OLD ]; then
	    mv $NEW $OLD
	  elif [ "$(cat $OLD | md5sum)" = "$(cat $NEW | md5sum)" ]; then
	    # toss the redundant copy
	    rm $NEW
	  fi
	  # Otherwise, we leave the .new copy for the admin to consider...
	}
	EOT
  else
    echo -n "" > install/doinst.sh.1
  fi
  # Only keep lines that deal with symlinks in bin/32 and lib directories:
  ( cat install/doinst.sh |grep -v "etc/ld.so.conf" \
      |grep -E '(usr/bin |lib |lib/)' > install/doinst.sh.2
    cat install/doinst.sh.1 install/doinst.sh.2 \
      |sed -e 's#usr/bin#usr/bin/32#g' > install/doinst.sh
    rm -f install/doinst.sh.1 install/doinst.sh.2 ) || true
fi

# The cxxlibs need some extra consideration because the libraries in
# /usr/i486-slackware-linux/lib will not be found by Slackware64.
# Note that as of Slackware 14, "usr/i486-slackware-linux" is gone:
if [ "$PKGNAM" = "cxxlibs" ]; then
  if [ -e usr/i486-slackware-linux ] ; then
    mkdir -p usr/lib  # just in case
    for OLIB in $(find usr/i486-slackware-linux/lib -type f -maxdepth 1) ; do
      cp -a $OLIB usr/lib/
    done
    cat install/doinst.sh | grep '/i486-slackware-linux' > install/doinst.sh.2
    cat install/doinst.sh.2 | sed -e 's#/i486-slackware-linux##g' >> install/doinst.sh
    rm -f install/doinst.sh.2
  fi
fi

# The qt package installs several symlinks to /usr/bin which point to
# binaries in qt's lib directory. We have to strip those from the -compat32
# package. If you want to build 32bit software that needs these qt binaries,
# you will have to add /usr/lib/qt/bin/ to your $PATH
# We will remove a lot of stuff which we do not need in the compat32 package
# 
if [ "$PKGNAM" = "qt" -o "$PKGNAM" = "qt3" ]; then

  if [ -d usr/lib/qt ] ; then
    for ITEM in q3porting.xml demos doc examples ; do
      if [ -e "usr/lib/qt/$ITEM" ] ; then
        rm -rf "usr/lib/qt/$ITEM"
      fi
    done
  fi

  cat install/doinst.sh | grep -v 'usr/bin' | grep -v 'opt/kde3/bin' \
    > install/doinst.sh.2
  cat install/doinst.sh.2 > install/doinst.sh
  rm -f install/doinst.sh.2

fi

# Write the mangled script to $OUTPUT:
cat install/doinst.sh > $OUTPUT/$PKGNAM32

echo "The dsinst.sh script has been extracted and converted."