Merge branch tar-output into main

Closes: !29

1 files changed, 18 insertions, 1 deletions

diff --git a/bin/debvm-create b/bin/debvm-create
index 8c86eca..41a6139 100755
--- a/bin/debvm-create
+++ b/bin/debvm-create
@@ -69,6 +69,12 @@ Skips adding a the customize-autologin.sh to B<mmdebstrap> that configures
 automatic root login on a serial console and also parses the C<TERM> kernel
 cmdline and passes it as C<TERM> to B<agetty>.
 
+=item B<ext4>
+
+Internally, B<mmdebstrap> creates a tar archive first and converts that to ext2, which is then upgraded to ext4.
+This option causes the conversion to ext2 and further steps to be skipped and the output image will be a tar archive instead.
+Such a tar archive is not suitable for being booted by B<debvm-run>.
+
 =item B<kernel>
 
 skips installing a linux kernel image.
@@ -229,11 +235,17 @@ if ! check_skip kernel; then
 	set -- "--customize-hook=$SHARE_DIR/customize-kernel.sh" "$@"
 fi
 
+MMFORMAT=ext2
+# output a tarball if the ext4 step is skipped
+if check_skip ext4; then
+	MMFORMAT=tar
+fi
+
 # construct mmdebstrap options as $@:
 set -- \
 	--verbose \
 	--variant=apt \
-	--format=ext2 \
+	"--format=$MMFORMAT" \
 	--include=init \
 	"--architecture=$ARCHITECTURE" \
 	'--customize-hook=echo "LABEL=debvm / ext4 defaults 0 1" >"$1/etc/fstab"' \
@@ -293,6 +305,11 @@ set -ex
 
 mmdebstrap "$@"
 
+{ set +x; } 2>/dev/null
+check_skip ext4 && exit
+
+set -x
+
 truncate -s ">$SIZE" "$IMAGE"
 /sbin/tune2fs -L debvm -c 0 -i 0 -O dir_index,dir_nlink,extents,extra_isize,flex_bg,has_journal,huge_file "$IMAGE"
 /sbin/resize2fs -b "$IMAGE"