pack a shell script and its depending files as a single executable file

shell_pack.sh

#!/bin/bash - 
#===============================================================================
#
#          FILE: shell_pack.sh
# 
#         USAGE: ./shell_pack.sh 
# 
#   DESCRIPTION: 
# 
#       OPTIONS: ---
#  REQUIREMENTS: ---
#          BUGS: ---
#         NOTES: ---
#        AUTHOR: lwq (28120), scue@vip.qq.com
#  ORGANIZATION: 
#       CREATED: 04/22/2015 02:38:01 PM CST
#      REVISION:  ---
#===============================================================================

#===  FUNCTION  ================================================================
#         NAME:  usage
#  DESCRIPTION:  Display usage information.
#===============================================================================
function usage ()
{
        cat <<- EOT

  Usage :  $0 -p package -s script file1 file2 file3 ..

  Options:
  -h|help       Display this message
  -p|package    The output package name
  -s|script     The script will run when unpack package
  Other         The all files what you want to pack

EOT
}    # ----------  end of function usage  ----------

#-----------------------------------------------------------------------
#  Handle command line arguments
#-----------------------------------------------------------------------

while getopts ":hp:s:" opt
do
  case $opt in

    h|help    ) usage; exit 0   ;;
    p|package ) package_name=$OPTARG ;;
    s|script  ) install_script=$OPTARG ;;
    \?        ) echo -e "\n  Option does not exist : $OPTARG\n"
          usage; exit 1   ;;

  esac    # --- end of case ---
done
shift $(($OPTIND-1))

if [[ -z $package_name ]]; then
    echo "package_name can't not be empty"
    usage
    exit
fi

if [[ -z $package_name ]]; then
    echo "install_script can't not be empty"
    usage
    exit
fi

files=$@

generate_wrapper_script(){
    local install_script=$1
    local wrapper_script=$2
    cat <<-'EOT' >$wrapper_script
#!/bin/sh
echo "begin ..."
unpackdir=/tmp/$(basename $0)_unpack
rm -rf $unpackdir 2>/dev/null
mkdir -p $unpackdir
echo "unpacking ..."
sed '1, /^#__SCRIPTEND__/d' $0 | tar zxf - -C $unpackdir
if [ $? -ne 0 ]; then
    echo "unpack package failed."
    exit 1
fi
echo ""
echo "installing ..."
cd $unpackdir
EOT
    cat <<-EOR >>$wrapper_script
chmod +x $install_script
./$install_script
EOR
    cat <<-'EOE' >>$wrapper_script
if [ $? -ne 0 ]; then
    echo "install failed."
    exit 2
elif [[ -d $unpackdir ]]; then
    rm -rf $unpackdir
fi
echo "install ok, enjoy!"
exit 0
#__SCRIPTEND__
EOE
}

tarfile=package_content_$$.tgz
wrapfile=wrap_$$.sh

echo -e "start packing ..\n"
tar zcvf $tarfile $files $install_script
generate_wrapper_script $install_script $wrapfile
cat $wrapfile $tarfile > $package_name
chmod +x $package_name

echo -e "\noutput: $package_name\n"

rm -f $tarfile
rm -f $wrapfile