build and convert implementations

centos: WIP

Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>

templates/vmbuilder.sh

@@ -0,0 +1,116 @@
+#!/usr/bin/env bash
+
+OUT="/dev/null"
+
+if [[ -n "$DEBUG" ]]; then
+  set -x
+  OUT="/dev/stderr"
+fi
+set -e
+
+SRC=${1:-rootfs.tar}
+DISK_NAME=${2:-disk0}
+SIZE=${3:-10G}
+
+BLOCK="$DISK_NAME.raw"
+QCOW2="$DISK_NAME.qcow2"
+MOUNTPOINT=/mnt
+
+cleanup() {
+  rm -rf $BLOCK
+}
+
+make_img() {
+  echo "Creating raw image of size $SIZE"
+  fallocate -l $SIZE $BLOCK &> $OUT
+  (
+  echo n # Add a new partition
+  echo p # Primary partition
+  echo 1 # Partition number
+  echo   # First sector (Accept default: 1)
+  echo   # Last sector (Accept default: varies)
+  echo a
+  echo w # Write changes
+  ) | fdisk $BLOCK &> $OUT
+}
+
+mount_img() {
+  echo "Mounting image"
+  DEVICE_ROOT=$(losetup --show -f $BLOCK)
+  kpartx -v -a $DEVICE_ROOT &> $OUT
+  DEVICE=/dev/mapper/"$(basename ${DEVICE_ROOT})p1"
+  mkfs.ext4 $DEVICE &> $OUT
+  mount $DEVICE $MOUNTPOINT
+}
+
+unmount_img() {
+  echo "Unmounting image"
+  umount $MOUNTPOINT/
+  kpartx -d $DEVICE_ROOT &> $OUT
+  losetup -d $DEVICE_ROOT &> $OUT
+}
+
+copy_rootfs() {
+  echo "Copying root file system"
+  tar -xvf $SRC -C $MOUNTPOINT &> $OUT
+}
+
+setup_rootfs() {
+  echo "Setting up root file system"
+  uuid=$(blkid -s UUID -o value $DEVICE)
+
+  mkdir -p $MOUNTPOINT/etc/
+  echo "UUID=$uuid / ext4 errors=remount-ro 0 1" > $MOUNTPOINT/etc/fstab
+
+  echo "nameserver 8.8.8.8" > $MOUNTPOINT/etc/resolv.conf
+
+  echo localhost > $MOUNTPOINT/etc/hostname
+
+  cat <<EOF > $MOUNTPOINT/etc/hosts
+127.0.0.1 localhost
+
+# The following lines are desirable for IPv6 capable hosts
+::1 ip6-localhost ip6-loopback
+fe00::0 ip6-localnet
+ff00::0 ip6-mcastprefix
+ff02::1 ip6-allnodes
+ff02::2 ip6-allrouters
+ff02::3 ip6-allhosts
+EOF
+
+  rm -rf $MOUNTPOINT/usr/sbin/policy-rc.d
+}
+
+install_kernel() {
+  echo "Installing linux kernel"
+  extlinux --install $MOUNTPOINT/boot/ &> $OUT
+
+  cat <<EOF > $MOUNTPOINT/boot/syslinux.cfg
+DEFAULT linux
+  SAY Now booting the kernel from EXTLINUX...
+ LABEL linux
+  KERNEL /boot/vmlinuz
+  APPEND ro root=/dev/sda1 initrd=/boot/initrd.img net.ifnames=0 console=tty0 console=ttyS0,115200n8
+EOF
+}
+
+setup_mbr() {
+  echo "Setting up boot loader"
+  dd if=/usr/lib/EXTLINUX/mbr.bin of=$BLOCK bs=440 count=1 conv=notrunc &> $OUT
+}
+
+convert() {
+  echo "Converting image to QCOW2"
+  echo ""
+  qemu-img convert $BLOCK -O qcow2 $QCOW2
+}
+
+cleanup
+make_img
+mount_img
+copy_rootfs
+setup_rootfs
+install_kernel
+unmount_img
+setup_mbr
+convert