diskimage-builder/elements/redhat-common/bin/extract-image
Ben Nemec 16be6d7ce0 set -u and -o pipefail everywhere
As with the previous similar changes, this is intended to catch
problems as they happen instead of ignoring them and continuing on
to potentially fail later.  Setting this on all existing scripts
will allow us to enforce use via Jenkins.

Change-Id: Iad2d490c86dceab148ea9ab08f457c49a5d5352e
2014-05-06 15:51:07 -05:00

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#!/bin/bash
# Intended to be called from the root.d cloud-image script as follows:
# $TMP_HOOKS_PATH/bin/extract-image $BASE_IMAGE_FILE $BASE_IMAGE_TAR $IMAGE_LOCATION $CACHED_IMAGE
set -eu
set -o pipefail
BASE_IMAGE_FILE=$1
BASE_IMAGE_TAR=$2
IMAGE_LOCATION=$3
CACHED_IMAGE=$4
CACHED_TAR=$DIB_IMAGE_CACHE/$BASE_IMAGE_TAR
DIB_LOCAL_IMAGE=${DIB_LOCAL_IMAGE:-""}
if [ -n "$DIB_OFFLINE" -a -f "$CACHED_TAR" ] ; then
echo "Not checking freshness of cached $CACHED_TAR."
else
if [ -z "$DIB_LOCAL_IMAGE" ]; then
echo "Fetching Base Image"
# There seems to be some bad Fedora mirrors returning http 404's for the cloud image.
# If the image fails to download due to a 404 we retry once.
set +e
$TMP_HOOKS_PATH/bin/cache-url $IMAGE_LOCATION $CACHED_IMAGE
RV=$?
set -e
if [ "$RV" == "44" ] ; then
$TMP_HOOKS_PATH/bin/cache-url $IMAGE_LOCATION $CACHED_IMAGE
elif [ "$RV" != "0" ] ; then
exit 1
fi
fi
if [ ! -f $CACHED_TAR -o \
$CACHED_IMAGE -nt $CACHED_TAR ] ; then
echo "Repacking base image as tarball."
WORKING=$(mktemp -d)
EACTION="rm -r $WORKING"
trap "$EACTION" EXIT
echo "Working in $WORKING"
RAW_FILE=$(basename $BASE_IMAGE_FILE)
RAW_FILE=${RAW_FILE#.qcow2}.raw
qemu-img convert -f qcow2 -O raw $CACHED_IMAGE $WORKING/$RAW_FILE
# WARNING: The mattdm image has the root filesystem on the second
# partition (p2). If he changes the image the MAGIC_BIT
# might also need to change.
# UPDATE to above warning alluding to Fedora18:
# F19 images have the rootfs partition on p1
MAGIC_BIT=p1
# kpartx fails if no /dev/loop* exists, "losetup -f" prints first unused
# loop device and creates it if it doesn't exist
sudo losetup -f
# XXX: Parsing stdout is dangerous, would like a better way to discover
# the device used for the image.
# NOTE: On F17 (parted-3.0-10.fc17.x86_64), partprobe of
# /dev/loop0 does not create /dev/loop0p2, while kpartx at
# least creates /dev/mapper/loop0p2.
LOOPDEV=$(sudo kpartx -av $WORKING/$RAW_FILE | awk "/loop[0-9]+$MAGIC_BIT/ {print \$3}")
if ! timeout 5 sh -c "while ! [ -e /dev/mapper/$LOOPDEV ]; do sleep 1; done"; then
echo "Error: Could not find /dev/mapper/$LOOPDEV"
exit 1
fi
EACTION="sudo kpartx -d $WORKING/$RAW_FILE;$EACTION"
trap "$EACTION" EXIT
mkdir $WORKING/mnt
sudo mount /dev/mapper/$LOOPDEV $WORKING/mnt
EACTION="sudo umount -f $WORKING/mnt;$EACTION"
trap "$EACTION" EXIT
# Chroot in so that we get the correct uid/gid
sudo chroot $WORKING/mnt bin/tar -cz . > $WORKING/tmp.tar
mv $WORKING/tmp.tar $CACHED_TAR
else
echo "Using cached tar from $CACHED_TAR"
fi
fi
# Extract the base image (use --numeric-owner to avoid UID/GID mismatch between
# image tarball and host OS e.g. when building Fedora image on an openSUSE host)
echo "Extracting base root image from $CACHED_TAR"
sudo tar -C $TARGET_ROOT --numeric-owner -xzf $CACHED_TAR
if [ -e "$TARGET_ROOT/lost+found" ]; then
sudo rmdir $TARGET_ROOT/lost+found
fi