mmdebstrap/make_mirror.sh

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2018-09-18 09:20:24 +00:00
#!/bin/sh
set -eu
# This script fills either cache.A or cache.B with new content and then
# atomically switches the cache symlink from one to the other at the end.
# This way, at no point will the cache be in an non-working state, even
# when this script got canceled at any point.
# Working with two directories also automatically prunes old packages in
# the local repository.
deletecache() {
dir="$1"
echo "running deletecache $dir">&2
if [ ! -e "$dir" ]; then
return
fi
if [ ! -e "$dir/mmdebstrapcache" ]; then
echo "$dir cannot be the mmdebstrap cache" >&2
return 1
fi
# be very careful with removing the old directory
for dist in stable testing unstable; do
for variant in minbase buildd -; do
if [ -e "$dir/debian-$dist-$variant.tar" ]; then
rm "$dir/debian-$dist-$variant.tar"
else
echo "does not exist: $dir/debian-$dist-$variant.tar" >&2
fi
done
if [ -e "$dir/debian/dists/$dist" ]; then
rm --one-file-system --recursive "$dir/debian/dists/$dist"
else
echo "does not exist: $dir/debian/dists/$dist" >&2
fi
if [ "$dist" = "stable" ]; then
if [ -e "$dir/debian/dists/stable-updates" ]; then
rm --one-file-system --recursive "$dir/debian/dists/stable-updates"
else
echo "does not exist: $dir/debian/dists/stable-updates" >&2
fi
if [ -e "$dir/debian-security/dists/stable/updates" ]; then
rm --one-file-system --recursive "$dir/debian-security/dists/stable/updates"
else
echo "does not exist: $dir/debian-security/dists/stable/updates" >&2
fi
fi
done
if [ -e $dir/debian-*.qcow ]; then
rm --one-file-system "$dir"/debian-*.qcow
else
echo "does not exist: $dir/debian-*.qcow" >&2
fi
if [ -e "$dir/debian/pool/main" ]; then
rm --one-file-system --recursive "$dir/debian/pool/main"
else
echo "does not exist: $dir/debian/pool/main" >&2
fi
if [ -e "$dir/debian-security/pool/updates/main" ]; then
rm --one-file-system --recursive "$dir/debian-security/pool/updates/main"
else
echo "does not exist: $dir/debian-security/pool/updates/main" >&2
fi
for i in $(seq 1 6); do
if [ ! -e "$dir/debian$i" ]; then
continue
fi
rm "$dir/debian$i"
done
rm "$dir/mmdebstrapcache"
# now the rest should only be empty directories
if [ -e "$dir" ]; then
find "$dir" -depth -print0 | xargs -0 --no-run-if-empty rmdir
else
echo "does not exist: $dir" >&2
fi
}
cleanup_newcachedir() {
echo "running cleanup_newcachedir"
deletecache "$newcachedir"
}
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get_oldaptnames() {
if [ ! -e "$1/$2" ]; then
return
fi
gzip -dc "$1/$2" \
| grep-dctrl --no-field-names --show-field=Package,Version,Architecture,Filename '' \
| paste -sd " \n" \
| while read name ver arch fname; do
if [ ! -e "$1/$fname" ]; then
continue
fi
# apt stores deb files with the colon encoded as %3a while
# mirrors do not contain the epoch at all #645895
case "$ver" in *:*) ver="${ver%%:*}%3a${ver#*:}";; esac
aptname="$rootdir/var/cache/apt/archives/${name}_${ver}_${arch}.deb"
# we have to cp and not mv because other
# distributions might still need this file
# we have to cp and not symlink because apt
# doesn't recognize symlinks
cp --link "$1/$fname" "$aptname"
echo "$aptname"
done
}
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get_newaptnames() {
if [ ! -e "$1/$2" ]; then
return
fi
# skip empty files by trying to uncompress the first byte of the payload
if [ "$(gzip -dc "$1/$2" | head -c1 | wc -c)" -eq 0 ]; then
return
fi
gzip -dc "$1/$2" \
| grep-dctrl --no-field-names --show-field=Package,Version,Architecture,Filename,SHA256 '' \
| paste -sd " \n" \
| while read name ver arch fname hash; do
# sanity check for the hash because sometimes the
# archive switches the hash algorithm
if [ "${#hash}" -ne 64 ]; then
echo "expected hash length of 64 but got ${#hash} for: $hash" >&2
exit 1
fi
dir="${fname%/*}"
# apt stores deb files with the colon encoded as %3a while
# mirrors do not contain the epoch at all #645895
case "$ver" in *:*) ver="${ver%%:*}%3a${ver#*:}";; esac
aptname="$rootdir/var/cache/apt/archives/${name}_${ver}_${arch}.deb"
if [ -e "$aptname" ]; then
# make sure that we found the right file by checking its hash
echo "$hash $aptname" | sha256sum --check >&2
mkdir -p "$1/$dir"
# since we move hardlinks around, the same hardlink might've been
# moved already into the same place by another distribution.
# mv(1) refuses to copy A to B if both are hardlinks of each other.
if [ "$aptname" -ef "$1/$fname" ]; then
# both files are already the same so we just need to
# delete the source
rm "$aptname"
else
mv "$aptname" "$1/$fname"
fi
echo "$aptname"
fi
done
}
cleanupapt() {
echo "running cleanupapt" >&2
if [ ! -e "$rootdir" ]; then
return
fi
for f in \
"$rootdir/var/cache/apt/archives/"*.deb \
"$rootdir/var/cache/apt/archives/partial/"*.deb \
"$rootdir/var/cache/apt/"*.bin \
"$rootdir/var/lib/apt/lists/"* \
"$rootdir/var/lib/dpkg/status" \
"$rootdir/var/lib/dpkg/lock-frontend" \
"$rootdir/var/lib/dpkg/lock" \
"$rootdir/etc/apt/apt.conf" \
"$rootdir/etc/apt/sources.list" \
"$rootdir/oldaptnames" \
"$rootdir/newaptnames" \
"$rootdir/var/cache/apt/archives/lock"; do
if [ ! -e "$f" ]; then
echo "does not exist: $f" >&2
continue
fi
if [ -d "$f" ]; then
rmdir "$f"
else
rm "$f"
fi
done
find "$rootdir" -depth -print0 | xargs -0 --no-run-if-empty rmdir
}
# note: this function uses brackets instead of curly braces, so that it's run
# in its own process and we can handle traps independent from the outside
update_cache() (
dist="$1"
nativearch="$2"
# use a subdirectory of $newcachedir so that we can use
# hardlinks
rootdir="$newcachedir/apt"
mkdir -p "$rootdir"
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# we only set this trap here and overwrite the previous trap, because
# the update_cache function is run as part of a pipe and thus in its
# own process which will EXIT after it finished
trap "cleanupapt" EXIT INT TERM
for p in /etc/apt/apt.conf.d /etc/apt/sources.list.d /etc/apt/preferences.d /var/cache/apt/archives /var/lib/apt/lists/partial /var/lib/dpkg; do
mkdir -p "$rootdir/$p"
done
# read sources.list content from stdin
cat > "$rootdir/etc/apt/sources.list"
cat << END > "$rootdir/etc/apt/apt.conf"
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Apt::Architecture "$nativearch";
Apt::Architectures "$nativearch";
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Dir::Etc "$rootdir/etc/apt";
Dir::State "$rootdir/var/lib/apt";
Dir::Cache "$rootdir/var/cache/apt";
Apt::Install-Recommends false;
Apt::Get::Download-Only true;
Acquire::Languages "none";
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Dir::Etc::Trusted "/etc/apt/trusted.gpg";
Dir::Etc::TrustedParts "/etc/apt/trusted.gpg.d";
END
> "$rootdir/var/lib/dpkg/status"
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APT_CONFIG="$rootdir/etc/apt/apt.conf" apt-get update
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# before downloading packages and before replacing the old Packages
# file, copy all old *.deb packages from the mirror to
# /var/cache/apt/archives so that apt will not re-download *.deb
# packages that we already have
{
get_oldaptnames "$oldmirrordir" "dists/$dist/main/binary-$nativearch/Packages.gz"
if grep --quiet security.debian.org "$rootdir/etc/apt/sources.list"; then
get_oldaptnames "$oldmirrordir" "dists/stable-updates/main/binary-$nativearch/Packages.gz"
get_oldaptnames "$oldcachedir/debian-security" "dists/stable/updates/main/binary-$nativearch/Packages.gz"
fi
} | sort -u > "$rootdir/oldaptnames"
pkgs=$(APT_CONFIG="$rootdir/etc/apt/apt.conf" apt-get indextargets \
--format '$(FILENAME)' 'Created-By: Packages' "Architecture: $nativearch" \
| xargs --delimiter='\n' /usr/lib/apt/apt-helper cat-file \
| grep-dctrl --no-field-names --show-field=Package --exact-match \
\( --field=Essential yes --or --field=Priority required \
--or --field=Priority important --or --field=Priority standard \
\))
pkgs="$(echo $pkgs) build-essential busybox gpg eatmydata"
APT_CONFIG="$rootdir/etc/apt/apt.conf" apt-get --yes install $pkgs
# to be able to also test gpg verification, we need to create a mirror
mkdir -p "$newmirrordir/dists/$dist/main/binary-$nativearch/"
curl --location "$mirror/dists/$dist/Release" > "$newmirrordir/dists/$dist/Release"
curl --location "$mirror/dists/$dist/Release.gpg" > "$newmirrordir/dists/$dist/Release.gpg"
curl --location "$mirror/dists/$dist/main/binary-$nativearch/Packages.gz" > "$newmirrordir/dists/$dist/main/binary-$nativearch/Packages.gz"
if grep --quiet security.debian.org "$rootdir/etc/apt/sources.list"; then
mkdir -p "$newmirrordir/dists/stable-updates/main/binary-$nativearch/"
curl --location "$mirror/dists/stable-updates/Release" > "$newmirrordir/dists/stable-updates/Release"
curl --location "$mirror/dists/stable-updates/Release.gpg" > "$newmirrordir/dists/stable-updates/Release.gpg"
curl --location "$mirror/dists/stable-updates/main/binary-$nativearch/Packages.gz" > "$newmirrordir/dists/stable-updates/main/binary-$nativearch/Packages.gz"
mkdir -p "$newcachedir/debian-security/dists/stable/updates/main/binary-$nativearch/"
curl --location "$security_mirror/dists/stable/updates/Release" > "$newcachedir/debian-security/dists/stable/updates/Release"
curl --location "$security_mirror/dists/stable/updates/Release.gpg" > "$newcachedir/debian-security/dists/stable/updates/Release.gpg"
curl --location "$security_mirror/dists/stable/updates/main/binary-$nativearch/Packages.gz" > "$newcachedir/debian-security/dists/stable/updates/main/binary-$nativearch/Packages.gz"
fi
# the deb files downloaded by apt must be moved to their right locations in the
# pool directory
#
# Instead of parsing the Packages file, we could also attempt to move the deb
# files ourselves to the appropriate pool directories. But that approach
# requires re-creating the heuristic by which the directory is chosen, requires
# stripping the epoch from the filename and will break once mirrors change.
# This way, it doesn't matter where the mirror ends up storing the package.
{
get_newaptnames "$newmirrordir" "dists/$dist/main/binary-$nativearch/Packages.gz";
if grep --quiet security.debian.org "$rootdir/etc/apt/sources.list"; then
get_newaptnames "$newmirrordir" "dists/stable-updates/main/binary-$nativearch/Packages.gz"
get_newaptnames "$newcachedir/debian-security" "dists/stable/updates/main/binary-$nativearch/Packages.gz"
fi
} | sort -u > "$rootdir/newaptnames"
rm "$rootdir/var/cache/apt/archives/lock"
rmdir "$rootdir/var/cache/apt/archives/partial"
# remove all packages that were in the old Packages file but not in the
# new one anymore
comm -23 "$rootdir/oldaptnames" "$rootdir/newaptnames" | xargs --delimiter="\n" --no-run-if-empty rm
# now the apt cache should be empty
if [ ! -z "$(ls -1qA "$rootdir/var/cache/apt/archives/")" ]; then
echo "$rootdir/var/cache/apt/archives not empty:"
ls -la "$rootdir/var/cache/apt/archives/"
exit 1
fi
APT_CONFIG="$rootdir/etc/apt/apt.conf" apt-get --option Dir::Etc::SourceList=/dev/null update
APT_CONFIG="$rootdir/etc/apt/apt.conf" apt-get clean
cleanupapt
# this function is run in its own process, so we unset all traps before
# returning
trap "-" EXIT INT TERM
)
if [ -e "./shared/cache.A" ] && [ -e "./shared/cache.B" ]; then
echo "both ./shared/cache.A and ./shared/cache.B exist" >&2
echo "was a former run of the script aborted?" >&2
if [ -e ./shared/cache ]; then
echo "cache symlink points to $(readlink ./shared/cache)" >&2
case "$(readlink ./shared/cache)" in
cache.A)
echo "maybe rm -r ./shared/cache.B" >&2
;;
cache.B)
echo "maybe rm -r ./shared/cache.A" >&2
;;
*)
echo "unexpected" >&2
esac
fi
exit 1
fi
if [ -e "./shared/cache.A" ]; then
oldcache=cache.A
newcache=cache.B
else
oldcache=cache.B
newcache=cache.A
fi
oldcachedir="./shared/$oldcache"
newcachedir="./shared/$newcache"
oldmirrordir="$oldcachedir/debian"
newmirrordir="$newcachedir/debian"
mirror="http://deb.debian.org/debian"
security_mirror="http://security.debian.org/debian-security"
components=main
: "${DEFAULT_DIST:=unstable}"
: "${HAVE_QEMU:=yes}"
: "${RUN_MA_SAME_TESTS:=yes}"
: "${HAVE_PROOT:=yes}"
# by default, use the mmdebstrap executable in the current directory
: "${CMD:=./mmdebstrap}"
if [ -e "$oldmirrordir/dists/$DEFAULT_DIST/Release" ]; then
http_code=$(curl --output /dev/null --silent --location --head --time-cond "$oldmirrordir/dists/$DEFAULT_DIST/Release" --write-out '%{http_code}' "$mirror/dists/$DEFAULT_DIST/Release")
case "$http_code" in
200) ;; # need update
304) echo up-to-date; exit 0;;
*) echo "unexpected status: $http_code"; exit 1;;
esac
fi
trap "cleanup_newcachedir" EXIT INT TERM
mkdir -p "$newcachedir"
touch "$newcachedir/mmdebstrapcache"
HOSTARCH=$(dpkg --print-architecture)
if [ "$HOSTARCH" = amd64 ]; then
arches="amd64 arm64 i386"
else
arches="$HOSTARCH"
fi
for nativearch in $arches; do
for dist in stable testing unstable; do
# non-host architectures are only downloaded for $DEFAULT_DIST
if [ $nativearch != $HOSTARCH ] && [ $DEFAULT_DIST != $dist ]; then
continue
fi
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cat << END | update_cache "$dist" "$nativearch"
deb [arch=$nativearch] $mirror $dist $components
END
if [ "$dist" = "stable" ]; then
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# starting wit bullseye, stable/updates becomes stable-security
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cat << END | update_cache "$dist" "$nativearch"
deb [arch=$nativearch] $mirror $dist $components
deb [arch=$nativearch] $mirror stable-updates main
deb [arch=$nativearch] $security_mirror stable/updates main
END
fi
done
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done
# Create some symlinks so that we can trick apt into accepting multiple apt
# lines that point to the same repository but look different. This is to
# avoid the warning:
# W: Target Packages (main/binary-all/Packages) is configured multiple times...
for i in $(seq 1 6); do
ln -s debian "$newcachedir/debian$i"
done
tmpdir=""
cleanuptmpdir() {
if [ -z "$tmpdir" ]; then
return
fi
if [ ! -e "$tmpdir" ]; then
return
fi
for f in "$tmpdir/extlinux.conf" \
"$tmpdir/worker.sh" \
"$tmpdir/mini-httpd" "$tmpdir/hosts" \
"$tmpdir/debian-chroot.tar" \
"$tmpdir/mmdebstrap.service" \
"$tmpdir/debian-$DEFAULT_DIST.img"; do
if [ ! -e "$f" ]; then
echo "does not exist: $f" >&2
continue
fi
rm "$f"
done
rmdir "$tmpdir"
}
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export SOURCE_DATE_EPOCH=$(date --date="$(grep-dctrl -s Date -n '' "$newmirrordir/dists/$DEFAULT_DIST/Release")" +%s)
if [ "$HAVE_QEMU" = "yes" ]; then
# We must not use any --dpkgopt here because any dpkg options still
# leak into the chroot with chrootless mode.
# We do not use our own package cache here because
# - it doesn't (and shouldn't) contain the extra packages
# - it doesn't matter if the base system is from a different mirror timestamp
# procps is needed for /sbin/sysctl
tmpdir="$(mktemp -d)"
trap "cleanuptmpdir; cleanup_newcachedir" EXIT INT TERM
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pkgs=perl-doc,systemd-sysv,perl,arch-test,fakechroot,fakeroot,mount,uidmap,qemu-user-static,binfmt-support,qemu-user,dpkg-dev,mini-httpd,libdevel-cover-perl,libtemplate-perl,debootstrap,procps,apt-cudf,aspcud,python3,libcap2-bin,gpg,debootstrap,distro-info-data,iproute2,ubuntu-keyring,apt-utils
if [ "$DEFAULT_DIST" != "stable" ]; then
pkgs="$pkgs,squashfs-tools-ng,genext2fs"
fi
if [ "$HAVE_PROOT" = "yes" ]; then
pkgs="$pkgs,proot"
fi
if [ ! -e ./mmdebstrap ]; then
pkgs="$pkgs,mmdebstrap"
fi
case "$HOSTARCH" in
amd64|arm64)
pkgs="$pkgs,linux-image-$HOSTARCH"
;;
i386)
pkgs="$pkgs,linux-image-686"
;;
ppc64el)
pkgs="$pkgs,linux-image-powerpc64le"
;;
*)
echo "no kernel image for $HOSTARCH" >&2
exit 1
;;
esac
if [ "$HOSTARCH" = amd64 ] && [ "$RUN_MA_SAME_TESTS" = "yes" ]; then
arches=amd64,arm64
pkgs="$pkgs,libfakechroot:arm64,libfakeroot:arm64"
else
arches=$HOSTARCH
fi
$CMD --variant=apt --architectures=$arches --include="$pkgs" \
$DEFAULT_DIST - "$mirror" > "$tmpdir/debian-chroot.tar"
cat << END > "$tmpdir/extlinux.conf"
default linux
timeout 0
label linux
kernel /vmlinuz
append initrd=/initrd.img root=/dev/vda1 rw console=ttyS0,115200
serial 0 115200
END
cat << END > "$tmpdir/mmdebstrap.service"
[Unit]
Description=mmdebstrap worker script
[Service]
Type=oneshot
ExecStart=/worker.sh
[Install]
WantedBy=multi-user.target
END
# here is something crazy:
# as we run mmdebstrap, the process ends up being run by different users with
# different privileges (real or fake). But for being able to collect
# Devel::Cover data, they must all share a single directory. The only way that
# I found to make this work is to mount the database directory with a
# filesystem that doesn't support ownership information at all and a umask that
# gives read/write access to everybody.
# https://github.com/pjcj/Devel--Cover/issues/223
cat << 'END' > "$tmpdir/worker.sh"
#!/bin/sh
echo 'root:root' | chpasswd
mount -t 9p -o trans=virtio,access=any mmdebstrap /mnt
# need to restart mini-httpd because we mounted different content into www-root
systemctl restart mini-httpd
handler () {
while IFS= read -r line || [ -n "$line" ]; do
printf "%s %s: %s\n" "$(date -u -d "0 $(date +%s.%3N) seconds - $2 seconds" +"%T.%3N")" "$1" "$line"
done
}
(
cd /mnt;
if [ -e cover_db.img ]; then
mkdir -p cover_db
mount -o loop,umask=000 cover_db.img cover_db
fi
now=$(date +%s.%3N)
ret=0
{ { { { {
sh -x ./test.sh 2>&1 1>&4 3>&- 4>&-; echo $? >&2;
} | handler E "$now" >&3;
} 4>&1 | handler O "$now" >&3;
} 2>&1;
} | { read xs; exit $xs; };
} 3>&1 || ret=$?
if [ -e cover_db.img ]; then
df -h cover_db
umount cover_db
fi
echo $ret
) > /mnt/result.txt 2>&1
umount /mnt
systemctl poweroff
END
chmod +x "$tmpdir/worker.sh"
# initially we serve from the new cache so that debootstrap can grab
# the new package repository and not the old
cat << END > "$tmpdir/mini-httpd"
START=1
DAEMON_OPTS="-h 127.0.0.1 -p 80 -u nobody -dd /mnt/$newcache -i /var/run/mini-httpd.pid -T UTF-8"
END
cat << 'END' > "$tmpdir/hosts"
127.0.0.1 localhost
END
#libguestfs-test-tool
#export LIBGUESTFS_DEBUG=1 LIBGUESTFS_TRACE=1
#
# In case the rootfs was prepared in fakechroot mode, ldconfig has to
# run to populate /etc/ld.so.cache or otherwise fakechroot tests will
# fail to run.
#
# The disk size is sufficient in most cases. Sometimes, gcc will do
# an upload with unstripped executables to make tracking down ICEs much
# easier (see #872672, #894014). During times with unstripped gcc, the
# buildd variant will not be 400MB but 1.3GB large and needs a 10G
# disk.
if [ -z ${DISK_SIZE+x} ]; then
DISK_SIZE=3G
fi
guestfish -N "$tmpdir/debian-$DEFAULT_DIST.img"=disk:$DISK_SIZE -- \
part-disk /dev/sda mbr : \
mkfs ext2 /dev/sda1 : \
mount /dev/sda1 / : \
tar-in "$tmpdir/debian-chroot.tar" / : \
command /sbin/ldconfig : \
copy-in "$tmpdir/extlinux.conf" / : \
mkdir-p /etc/systemd/system/multi-user.target.wants : \
ln-s ../mmdebstrap.service /etc/systemd/system/multi-user.target.wants/mmdebstrap.service : \
copy-in "$tmpdir/mmdebstrap.service" /etc/systemd/system/ : \
copy-in "$tmpdir/worker.sh" / : \
copy-in "$tmpdir/mini-httpd" /etc/default : \
copy-in "$tmpdir/hosts" /etc/ : \
touch /mmdebstrap-testenv : \
upload /usr/lib/SYSLINUX/mbr.bin /mbr.bin : \
copy-file-to-device /mbr.bin /dev/sda size:440 : \
rm /mbr.bin : \
extlinux / : \
sync : \
umount / : \
part-set-bootable /dev/sda 1 true : \
shutdown
qemu-img convert -O qcow2 "$tmpdir/debian-$DEFAULT_DIST.img" "$newcachedir/debian-$DEFAULT_DIST.qcow"
cleanuptmpdir
trap "cleanup_newcachedir" EXIT INT TERM
fi
mirror="http://127.0.0.1/debian"
for dist in stable testing unstable; do
for variant in minbase buildd -; do
echo "running debootstrap --no-merged-usr --variant=$variant $dist \${TEMPDIR} $mirror"
cat << END > shared/test.sh
#!/bin/sh
set -eu
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export LC_ALL=C.UTF-8
export SOURCE_DATE_EPOCH=$SOURCE_DATE_EPOCH
tmpdir="\$(mktemp -d)"
chmod 755 "\$tmpdir"
debootstrap --no-merged-usr --variant=$variant $dist "\$tmpdir" $mirror
tar --sort=name --mtime=@$SOURCE_DATE_EPOCH --clamp-mtime --numeric-owner --one-file-system --xattrs -C "\$tmpdir" -c . > "$newcache/debian-$dist-$variant.tar"
rm -r "\$tmpdir"
END
if [ "$HAVE_QEMU" = "yes" ]; then
cachedir=$newcachedir ./run_qemu.sh
else
./run_null.sh SUDO
fi
done
done
if [ "$HAVE_QEMU" = "yes" ]; then
# now replace the minihttpd config with one that serves the new repository
guestfish -a "$newcachedir/debian-$DEFAULT_DIST.qcow" -i <<EOF
upload -<<END /etc/default/mini-httpd
START=1
DAEMON_OPTS="-h 127.0.0.1 -p 80 -u nobody -dd /mnt/cache -i /var/run/mini-httpd.pid -T UTF-8"
END
EOF
fi
# delete possibly leftover symlink
if [ -e ./shared/cache.tmp ]; then
rm ./shared/cache.tmp
fi
# now atomically switch the symlink to point to the other directory
ln -s $newcache ./shared/cache.tmp
mv --no-target-directory ./shared/cache.tmp ./shared/cache
deletecache "$oldcachedir"
trap - EXIT INT TERM