#!/bin/sh
# Copyright 1997, 1998  Patrick Volkerding, Moorhead, MN USA
# Copyright 2002, 2004  Slackware Linux, Inc., Concord, CA USA
# All rights reserved.
#
# Redistribution and use of this script, with or without modification, is
# permitted provided that the following conditions are met:
#
# 1. Redistributions of this script must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
#
#  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
#  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
#  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
#  EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
#  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
#  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
#  OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
#  WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
#  OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
#  ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#

if [ "$1" = "" ]; then
  echo "$0:  Converts RPM format to standard GNU tar + GNU zip format."
  echo "            (view converted packages with \"less\", install and remove"
  echo "            with \"installpkg\", \"removepkg\", \"pkgtool\", or manually"
  echo "            with \"tar\")"
  echo
  echo "Usage:      $0 <file.rpm>"
  if [ "`basename $0`" = "rpm2tgz" ]; then
    echo "            (Outputs \"file.tgz\")"
  else
    echo "            (Outputs \"file.tar.gz\")"
  fi
  exit 1;
fi

# Create a new temporary directory with a secure filename:
make_temp_dir() {
  if [ -x "$(which mcookie)" ]; then
    tempd=/tmp/tmp.$(mcookie)
    mkdir -p -m 0755 $tempd
  elif [ -x "$(which openssl)" ]; then
    tempd=/tmp/tmp.$(dd if=/dev/urandom bs=1k count=1 2> /dev/null | openssl dgst -md5)
    mkdir -p -m 0755 $tempd
  elif [ -x "$(which md5)" ]; then
    tempd=/tmp/tmp.$(dd if=/dev/urandom bs=1k count=1 2> /dev/null | md5)
    mkdir -p -m 0755 $tempd
  elif [ -x "$(which mktemp)" ]; then
    tempd=$(mktemp -d)
    chmod 755 $tempd
  ## Uncomment for insecure use, but don't blame me:
  #else
  #  tempd=/tmp/tmp.$$
  #  mkdir -p -m 0755 $tempd
  fi
  if [ -d $tempd ]; then # success, return the name of the directory:
    echo $tempd
  else
    echo "ERROR:  Could not find mcookie, openssl, or md5."
    echo "        Exiting since a secure temporary directory could not be made."
    exit 1
  fi
}

for i in $* ; do
  
  # Determine if this is a source or binary RPM.
  # If we have getrpmtype, use that.  Otherwise, try "file".
  if which getrpmtype 1> /dev/null 2> /dev/null; then
    if getrpmtype -n $i | grep source 1> /dev/null 2> /dev/null ; then
      isSource=1
    else
      isSource=0
    fi
  else # use file.  This works fine on Slackware, and is the default.
    if file $i | grep RPM | grep " src " 1> /dev/null 2> /dev/null ; then
      isSource=1
    else
      isSource=0
    fi
  fi

  # Create a temporary directory:
  TMPDIR=$(make_temp_dir)

  # Extract the RPM:
  ofn=$TMPDIR/$(basename $i .rpm).cpio
  if which rpm2cpio 1> /dev/null 2> /dev/null ; then
    rpm2cpio $i > $ofn 2> /dev/null
    if [ ! $? = 0 ]; then
      echo "ERROR:  rpm2cpio failed.  (maybe $i is not an RPM?)"
      rm -rf $TMPDIR
      continue
    fi
  else # less reliable than rpm2cpio...
    ( dd ibs=`rpmoffset < $i` skip=1 if=$i 2> /dev/null | gzip -dc > $ofn 2>/dev/null ) || \
    ( dd ibs=`rpmoffset < $i` skip=1 if=$i 2> /dev/null | bzip2 -dc > $ofn 2>/dev/null )
  fi
  DEST=$TMPDIR
  if [ "$isSource" = "1" ]; then
     DEST=$DEST/$(basename $(basename $i .rpm) .src)
  fi
  mkdir -p $DEST
  ( cd $DEST
    cpio -i -m -d < $ofn 1> /dev/null 2> /dev/null
    rm -f $ofn
    find . -type d -perm 700 -exec chmod 755 {} \;
  )

  # Repack the files in a tar+gz archive:
  ( cd $TMPDIR ; tar cf - . ) > `basename $i .rpm`.tar
  gzip -9 `basename $i .rpm`.tar
  if [ "`basename $0`" = "rpm2tgz" ]; then
    mv `basename $i .rpm`.tar.gz `basename $i .rpm`.tgz
  fi

  # Remove temporary directory:
  rm -rf $TMPDIR

done