#!/bin/bash -
# febootstrap-to-supermin
# (C) Copyright 2009 Red Hat Inc.
#
# 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., 675 Mass Ave, Cambridge, MA 02139, USA.
#
# Written by Richard W.M. Jones <rjones@redhat.com>

unset CDPATH

TEMP=`getopt \
        -o '' \
        --long help \
        -n febootstrap-to-supermin -- "$@"`
if [ $? != 0 ]; then
    echo "febootstrap-to-supermin: problem parsing the command line arguments"
    exit 1
fi
eval set -- "$TEMP"

usage ()
{
    echo "Usage: febootstrap-to-supermin DIR supermin.img hostfiles.txt"
    echo "Please read febootstrap-to-supermin(8) man page for more information."
}

while true; do
    case "$1" in
	--help)
	    usage
	    exit 0;;
	--)
	    shift
	    break;;
	*)
	    echo "Internal error!"
	    exit 1;;
    esac
done

if [ $# -ne 3 ]; then
    usage
    exit 1
fi

set -e

# Create a temporary directory, make sure it gets cleaned up at the end.
tmpdir=$(mktemp -d)
remove_tmpdir ()
{
  status=$?
  rm -rf "$tmpdir" && exit $status
}
trap remove_tmpdir EXIT

# Get the complete list of files and directories in the appliance.
(cd "$1" > /dev/null && find) > "$tmpdir/files"

exec 5>"$tmpdir/keep"		# Files/dirs we will keep in supermin.img
exec 6>$3			# hostfiles.txt (output)
exec 7<"$tmpdir/files"

while read path <&7; do
    dir=$(dirname "$path")
    file=$(basename "$path")

    # Ignore fakeroot.log.
    if [ "$path" = "./fakeroot.log" ]; then
	:

    # Kernel modules are always copied in from the host, including all
    # the dependency information files.
    elif [[ "$path" =~ '^\./lib/modules/' ]]; then
	:

    # All we're going to keep are the special files /init, the daemon,
    # configuration files (/etc), devices and modifiable stuff (/var).
    elif [ "$path" = "./init" ]; then
        echo "$path" >&5

    elif [[ "$path" =~ '^\./etc' || "$path" =~ '^./dev' || "$path" =~ '^\./var' ]]; then
        echo "$path" >&5

    # Always write directory names to both output files.
    elif [ -d "$path" ]; then
        echo "$path" >&5
        echo "$path" >&6

    # Some libraries need fixed version numbers replaced by wildcards.
    elif [[ "$file" =~ '^ld-[.0-9]+\.so$' ]]; then
        echo "$dir/ld-*.so" >&6

    # libfoo-1.2.3.so
    elif [[ "$file" =~ '^lib(.*)-[-.0-9]+\.so$' ]]; then
        echo "$dir/lib${BASH_REMATCH[1]}-*.so" >&6

    # libfoo-1.2.3.so.1.2.3 (but NOT '*.so.N')
    elif [[ "$file" =~ '^lib(.*)-[-.0-9]+\.so\.([0-9]+)\.' ]]; then
        echo "$dir/lib${BASH_REMATCH[1]}-*.so.${BASH_REMATCH[2]}.*" >&6

    # libfoo.so.1.2.3 (but NOT '*.so.N')
    elif [[ "$file" =~ '^lib(.*)\.so\.([0-9]+)\.' ]]; then
        echo "$dir/lib${BASH_REMATCH[1]}.so.${BASH_REMATCH[2]}.*" >&6

    else
        # Anything else comes from the host directly.
        echo "$path" >&6
    fi
done

# Close output files.
exec 5>&-
exec 6>&-

# Now run febootstrap-to-initramfs to construct the supermin
# appliance.
if ! febootstrap-to-initramfs --nocompress --files="$tmpdir/keep" "$1" > "$2"
then
    rm -f "$2"
fi