#!/bin/bash
#
# Builds a Fedora Core reference image. Requires the build server to
# host a local yum repository in one of:
#
# /usr/share/mirrors/fedora
# /var/www/html/mirrors/fedora
#
# Otherwise, tries using CoBlitz:
#
# http://coblitz.planet-lab.org/pub/fedora
#
# Mark Huang <mlhuang@cs.princeton.edu>
# Copyright (C) 2004-2006 The Trustees of Princeton University
#
# $Id: build.sh,v 1.2 2005/10/01 18:20:08 mlhuang Exp $
#

export PATH=/sbin:/bin:/usr/sbin:/usr/bin

# Verbosity
verbose=0

# Default yum repositories to try
mirrors=(
file:///usr/share/mirrors/fedora
file:///var/www/html/mirrors/fedora
ftp://smoke.cs.princeton.edu/pub/mirrors/fedora
ftp://128.112.137.30/pub/mirrors/fedora
http://coblitz.planet-lab.org/pub/fedora
ftp://mirror.cs.princeton.edu/pub/mirrors/fedora
)

# Release and architecture to install
releasever=2
basearch=i386

# Yum groups to install
groups=(
"Core and Base"
)

# Packages to install
packages=()

usage()
{
    echo "Usage: mkfedora [OPTION]... [basedir]"
    echo "	-l url		Fedora mirror location. Defaults to try:"
    for mirror in "${mirrors[@]}" ; do
	echo "			$mirror"
    done
    echo "	-r release	Fedora release number (default: $releasever)"
    echo "	-a arch		Fedora architecture (default: $basearch)"
    echo "	-g group1 -g group2 ..."
    echo "			Additional yumgroups to install. Defaults:"
    for group in "${groups[@]}" ; do
	echo "			$group"
    done
    echo "	-p package1 -p package2 ..."
    echo "			Additional packages to install (default: none)"
    echo "	-v		Be verbose"
    echo "	-h		This message"
    exit 1
}

# Get options
while getopts "l:r:a:g:p:vh" opt ; do
    case $opt in
	l)
	    if echo $OPTARG | grep -q -i '^\(file\|http[s]*\)://' ; then
		mirrors=($OPTARG)
	    else
		mirrors=(file://$OPTARG)
	    fi
	    ;;
	r)
	    releasever=$OPTARG
	    ;;
	a)
	    basearch=$OPTARG
	    ;;
	g)
	    groups[${#groups[*]}]="$OPTARG"
	    ;;
	p)
	    packages[${#packages[*]}]="$OPTARG"
	    ;;
	v)
	    verbose=1
	    set -x
	    ;;
	h|*)
	    usage
	    ;;
    esac
done

shift $(($OPTIND - 1))
if [ ! -d "$1" ] ; then
    usage
fi

vroot=$(cd $1 && pwd -P)

if [ $UID -ne 0 ] ; then
    echo "Error: You must run this script as root."
    exit 1
fi

# Old versions of curl don't understand file:// URLs
fetch ()
{
    url=$1
    if curl --fail --silent --max-time 60 $url ; then
	return 0
    else
	if [ -f ${url#file://} ] ; then
	    cat ${url#file://}
	    return 0
	fi
    fi
    return 1
}

for mirror in "${mirrors[@]}" ; do
    baseurl=$mirror/linux/core/$releasever/$basearch/os
    if fetch $baseurl/repodata/repomd.xml >/dev/null ; then
	break
    fi
    unset baseurl
done

if [ -z "$baseurl" ] ; then
    echo "Error: linux/core/$releasever/$basearch/os/repodata/repomd.xml"
    echo "       could not be found in any of the following locations:"
    echo
    for mirror in ${mirrors[@]} ; do
	echo $mirror
    done
    echo
    usage
fi

exec 3>&1
exec 4>&2
if [ $verbose -eq 0 ] ; then
    exec 1>/dev/null
    exec 2>/dev/null
fi

# Scratch space
tmp=$(mktemp -d /tmp/mkfedora.XXXXXX)

# Initialize /dev in reference image
mkdir -p $vroot/dev
mknod -m 666 $vroot/dev/null c 1 3
mknod -m 666 $vroot/dev/zero c 1 5
mknod -m 666 $vroot/dev/full c 1 7
mknod -m 644 $vroot/dev/random c 1 8
mknod -m 644 $vroot/dev/urandom c 1 9
mknod -m 666 $vroot/dev/tty c 5 0
mknod -m 666 $vroot/dev/ptmx c 5 2
# For bash command substitution
ln -nsf ../proc/self/fd $vroot/dev/fd
# For df and linuxconf
touch $vroot/dev/hdv1

# Mount /dev/pts in reference image
mkdir -p $vroot/dev/pts
mount -t devpts none $vroot/dev/pts

# Mount /dev/shm in reference image
mkdir -p $vroot/dev/shm
mount -t tmpfs none $vroot/dev/shm

# Mount /proc in reference image
mkdir -p $vroot/proc
mount -t proc none $vroot/proc

cleanup ()
{
    umount $vroot/proc
    umount $vroot/dev/shm
    umount $vroot/dev/pts
    rm -rf $tmp
}

# Clean up before exiting if anything goes wrong
trap "cleanup; exit 1" ERR

# Create a dummy /etc/fstab in reference image
mkdir -p $vroot/etc
cat >$vroot/etc/fstab <<EOF
# This fake fstab exists only to please df and linuxconf.
/dev/hdv1	/	ext2	defaults	1 1
EOF
cp $vroot/etc/fstab $vroot/etc/mtab

# Prevent all locales from being installed in reference image
mkdir -p $vroot/etc/rpm
cat >$vroot/etc/rpm/macros <<EOF
%_install_langs en_US:en
%_excludedocs 1
%__file_context_path /dev/null
EOF

# Necessary for some scripts
mkdir -p $vroot/etc/sysconfig
echo "NETWORKING=yes" > $vroot/etc/sysconfig/network

# Trick rpm and yum, who read the real root /etc/rpm/macros file
# rather than the one installed in the reference image, despite what
# you might expect the --root and --installroot options to mean. Both
# programs always read $HOME/.rpmmacros.
export HOME=$vroot/tmp
mkdir -p $vroot/tmp
cp $vroot/etc/rpm/macros $vroot/tmp/.rpmmacros

# Initialize RPM database in reference image
mkdir -p $vroot/var/lib/rpm
rpm --root $vroot --initdb
rpm --root $vroot --import $baseurl/RPM-GPG-KEY-fedora

# Initialize yum in reference image
mkdir -p $vroot/var/cache/yum $vroot/var/log
cat >$vroot/etc/yum.conf <<EOF
[main]
cachedir=/var/cache/yum
debuglevel=2
logfile=/var/log/yum.log
pkgpolicy=newest
distroverpkg=redhat-release
tolerant=1
exactarch=1
retries=20
obsoletes=1
gpgcheck=0
# Prevent yum-2.4 from loading additional repository definitions
# (e.g., from /etc/yum.repos.d/)
reposdir=/dev/null

[base]
name=Fedora Core $releasever - $basearch - base
baseurl=$baseurl/
EOF

for optional in core/updates extras ; do
    if fetch $mirror/linux/$optional/$releasever/$basearch/repodata/repomd.xml ; then
	cat >>$vroot/etc/yum.conf <<EOF

[$(basename $optional)]
name=Fedora Core $releasever - $basearch - $(basename $optional)
baseurl=$mirror/linux/$optional/$releasever/$basearch/
EOF
    fi
done

# If we are being built as part of an automated RPM build, solve the
# bootstrap problem by including any just built packages in the yum
# configuration. This cooperates with the PlanetLab build system.
if [ -n "$RPM_BUILD_DIR" ] ; then
    RPM_RPMS_DIR=$(cd $(dirname $RPM_BUILD_DIR)/RPMS && pwd -P)
    yum-arch $RPM_RPMS_DIR || :
    createrepo $RPM_RPMS_DIR || :
    # If run under sudo, allow user to delete the headers/ and
    # repodata/ directories.
    if [ -n "$SUDO_USER" ] ; then
	chown -R $SUDO_USER $RPM_RPMS_DIR
    fi
    cat >>$vroot/etc/yum.conf <<EOF

[bootstrap]
name=Bootstrap - $basearch - $RPM_RPMS_DIR/
baseurl=file://$RPM_RPMS_DIR/
EOF

    # XXX Build system should generate yumgroups.xml automatically
fi

# The "Core" and "Base" groups are not uservisible by default in
# comps.xml, and old (Fedora Core 2) versions of yum will refuse to
# recognize them explicitly.
mkdir -p $tmp/corebase
cat >$tmp/corebase/yumgroups.xml <<EOF
<?xml version="1.0"?>
<!DOCTYPE comps PUBLIC "-//Red Hat, Inc.//DTD Comps info//EN" "comps.dtd">
<comps>
  <group>
    <id>corebase</id>
    <name>Core and Base</name>
    <default>true</default>
    <description>Core and Base Packages</description>
    <uservisible>true</uservisible>
    <grouplist>
      <groupreq>core</groupreq>
      <groupreq>base</groupreq>
    </grouplist>
  </group>
</comps>
EOF

# yum-2.0.x
yum-arch $tmp/corebase || :
# yum-2.4.x
createrepo -g yumgroups.xml $tmp/corebase || :

cat >>$vroot/etc/yum.conf <<EOF

[corebase]
name=Core and Base
baseurl=file://$tmp/corebase/
EOF

echo -n "* Installing base system..." >&3

# glibc must be specified explicitly for the correct arch to be chosen.
yum -c $vroot/etc/yum.conf --installroot=$vroot -y install glibc

# Go, baby, go
yum -c $vroot/etc/yum.conf --installroot=$vroot -y \
    groupinstall "${groups[@]}"

echo "done" >&3

if [ ${#packages[*]} -gt 0 ] ; then
    echo -n "* Installing optional packages..."
    yum -c $vroot/etc/yum.conf --installroot=$vroot -y \
	install "${packages[@]}"
    echo "done"
fi

# Clean yum cache
echo -n "* Cleaning up..." >&3
yum -c $vroot/etc/yum.conf --installroot=$vroot -y \
    clean all
echo "done" >&3

# Clean RPM state
rm -f $vroot/var/lib/rpm/__db*

# Disable all services in reference image
chroot $vroot /bin/sh -c "/sbin/chkconfig --list | awk '{ print \$1 }' | xargs -i /sbin/chkconfig {} off"

# Clean up
cleanup

exit 0