#!/bin/bash

source testboot.conf

# defaults
topdir=${topdir:-/opt/testboot}
dir=${dir:-$topdir}
dracutdir=${dracutdir:-$topdir/src/dracut}
anacondadir=${anacondadir:-$topdir/src/anaconda}
ram=${ram:-768}
disk=${disk:-$dir/disk.img}
disk2=${disk2:-$dir/disk2.img}
cdrom=${cdrom:-$dir/iso/Fedora-17-x86_64-DVD.iso}
graphics=${graphics:-vnc}
dracut_opts="${dracut_opts:---add anaconda --omit plymouth}"
network="${network:-default}"
vmname="${vmname:-testboot}"
compress=${compress:-$(type -P pigz || type -P xz)}
rebuild="${rebuild:-false}"

[ "$compress" = "xz" ] && compress="xz --check-crc32 -1"

printhelp() {
cat << __EOT__
Usage: $(basename $0) [OPTION...] [KERNEL ARGS...]
Boot a Fedora(ish) iso in a VM with the given kernel args.

  -h, --help            show this help
  -m, --ram=RAM         create VM with this much ram (in MB)
  -c, --virtconsole     add a virtual console device (hvc0)
  -s, --serialconsole   add a serial console device (ttyS0)
  -t, --text            create VM with no graphics (console output on-screen)
  -d, --fromcd          boot from the CDROM device
      --nocd            don't attach the CDROM device
      --dualnic         create VM with two NICs
      --nonic           create VM with no NICs

Edit testboot.conf to configure the paths and the ISO to use.
__EOT__
}


usecd="true"
usenet="true"
ARGS=$(getopt --options "hdcsrtm:" \
  --longoptions "help,fromcd,nocd,virtconsole,serialconsole,text,dualnic,nonic,rebuild,ram:"\
  --name testboot.sh \
  -- "$@") || exit 1
eval set -- "$ARGS"
while :; do case "$1" in
    -h|--help) printhelp; exit 0;;
    -d|--fromcd) fromcd="true"; shift;;
    --nocd) usecd=""; shift;;
    --dualnic) dualnic="true"; shift;;
    --nonic) dualnic=""; usenet=""; nonet="true"; shift;;
    -c|--virtconsole) console="--console pty"; shift;;
    -s|--serialconsole) console="--serial pty"; shift;;
    -t|--text) graphics="none"; shift;;
    -m|--ram) ram="$2"; shift 2;;
    -r|--rebuild) rebuild="true"; shift;;
    --) shift; break;;
    *) echo "getopt parse error"; exit 1 ;;
esac; done

if [ ! -f $cdrom ]; then
    echo "Can't find cdrom!"
    exit 1
fi

[ $(id -u) = 0 ] || { echo "be root."; exit 1; }
chcon -t virt_content_t $cdrom

initrd_unpack() {
    local cat=cat img="$1" outdir="$2"
    case `file $1` in
        *:\ gzip*)       cat=zcat ;;
        *:\ xz*|*:\ XZ*)  cat=xzcat ;;
    esac
    rm -rf $outdir $outdir.tmp; mkdir -p $outdir.tmp
    ( cd $outdir.tmp ; $cat $img | cpio -iumd 2>/dev/null )
    mv $outdir.tmp $outdir
}

get_modules() {
    echo -n "finding kernel version..."
    moddir=$(find $1 -name "modules.dep")
    moddir=${moddir%/modules.dep}
    kv=${moddir##*/}
    echo "$kv" | tee $dir/vmlinuz.kv
    if [ ! -d /lib/modules/$kv ]; then
        echo -n "getting modules..."
        cp -a $moddir /lib/modules/$kv
        echo "done"
    fi
}

apply_updates() {
    (
        cd $dir/updates
        find . -depth -type d | while read d; do
            [ ! -d "../initramfs/$d" ] && mkdir -p "../initramfs/$d"
        done
        find . -depth \! -type d | while read f; do
            cp -a "$f" "../initramfs/$f"
            echo "  ${f#.}"
        done
    )
}

initrd_cpio() {
    ( cd $dir/initramfs; find . | cpio -co ) 2>/dev/null
}

# TODO: check for $dracutdir/dracut.sh and git pull otherwise
setup_dracut() {
    if [ ! -f $dracutdir/modules.d/80anaconda/parse-kickstart ]; then
        if [ ! -d $anacondadir/dracut ]; then
            # TODO: git pull
            echo "ERROR: can't find anaconda dracut module :/"
            exit 1
        else
            ln -s $anacondadir/dracut $dracutdir/modules.d/80anaconda
        fi
    fi
}

grab_kernel_and_initrd() {
    local cdrom="$1" kernel="$2" initrd="$3" mnt="$dir/.mnt"
    umount $mnt &>/dev/null
    mkdir -p $mnt
    mount -o ro,loop $cdrom $mnt || { echo "failed to mount cdrom!"; exit 1; }
    cp -f $mnt/isolinux/vmlinuz $kernel
    cp -f $mnt/isolinux/initrd.img $initrd
    umount $mnt
    rmdir $mnt
}

if [ "$fromcd" != "true" ]; then
    kernel_args="$@"

    # check RAM
    if [ "$ram" -lt 768 ]; then
        kernel_args="$* inst.memcheck=0"
        echo "adding inst.memcheck=0 to kernel args"
    fi

    # do we need to pull out the kernel/modules?
    vmlinuz="$dir/vmlinuz"
    [ -e $vmlinuz.kv ] && kv=$(< $vmlinuz.kv)
    if [ $cdrom -nt $vmlinuz -o -z "$kv" -o ! -d /lib/modules/$kv ]; then
        echo "getting kernel and modules"
        grab_kernel_and_initrd $cdrom $vmlinuz $dir/initrd.img.orig
        initrd_unpack $dir/initrd.img.orig $dir/initramfs.orig
        get_modules $dir/initramfs.orig # sets $kv
        # force rebuild of initrd.img
        rm -rf $dir/initramfs
    fi

    # do we need to create the initramfs dir?
    initrd="$dir/initrd.img"
    if [ ! -d $dir/initramfs ]; then
        if [ "$rebuild" == "true" ]; then
            echo "rebuilding initramfs"
            setup_dracut
            (
                cd $dracutdir
                ./dracut.sh --local --no-compress --nomdadmconf --nolvmconf \
                                 --prefix /run/initramfs $dracut_opts \
                                 --force $dir/.initrd.cpio $kv
            ) || exit 1
            initrd_unpack $dir/.initrd.cpio $dir/initramfs
            cp $dir/initramfs.orig/.buildstamp $dir/initramfs/.buildstamp
            # force rebuild of initrd.img
            rm -rf $initrd
        else
            echo "copying initramfs"
            cp -a $dir/initramfs.orig $dir/initramfs
        fi
    fi

    # do we need to build initrd.img from initramfs?
    if [ ! -e $initrd ] || \
      find initramfs updates -newer $initrd | grep -q .; then
        if [ -d updates ]; then
            echo "applying updates to initramfs"
            apply_updates
        fi
        echo "making initrd.img"
        initrd_cpio | $compress -c > $dir/.initrd.tmp || exit 1
        mv -f $dir/.initrd.tmp $initrd
    fi

    bootarg="kernel=$vmlinuz,initrd=$initrd,kernel_args=$kernel_args"
fi

echo "Creating '$vmname' guest..."
virsh destroy $vmname &>/dev/null
virsh undefine $vmname &>/dev/null
virt-install --name $vmname --ram $ram --graphics $graphics \
  --os-type linux --os-variant fedora16 $console \
  --disk $disk,size=10 --disk $disk2,size=10 \
  ${nonet:+--nonetworks} \
  ${usenet:+--network network=$network,model=virtio,mac=52:54:00:03:31:38} \
  ${dualnic:+--network network=$network,model=virtio,mac=52:54:00:03:31:39} \
  ${usecd:+--disk $cdrom,device=cdrom} \
  ${bootarg:+--boot "$bootarg"}
virsh destroy $vmname &>/dev/null

# historical interest: this is how it'd work in qemu
do_qemu() {
    echo "starting qemu"
    echo "C-a x to exit, C-a c for console monitor"
    qemu-kvm -m $ram -kernel $kernel -initrd $initrd \
      -cdrom $cdrom -nographic -append $kernel_args
}