makechrootpkg: delete_chroot: Fix the is-btrfs-subvolume check.

First of all, it ran `is_btrfs "$chrootdir"` to decide if it was on
btrfs, but $chrootdir wasn't defined locally; it just happens to work
because $chrootdir was defined in main().  (I noticed this because in
Parabola, it is called differently, so $chrootdir was empty).

So I was tempted to just change it to `is_btrfs "$copydir"`, but if
$copydir is just a regular directory on a btrfs filesystem, then it
It would leave much of $copydir intact.  What we really care about is
if $copydir is a btrfs subvolume; which we can check by combining the
is_btrfs check with inspecting the inum of the directory.

I put this combined check in lib/archroot.sh:is_subvolume.

https://lists.archlinux.org/pipermail/arch-projects/2013-September/003901.html

1 files changed, 1 insertions, 1 deletions

diff --git a/makechrootpkg.in b/makechrootpkg.in
index 3aa5f01..196cbe9 100644
--- a/makechrootpkg.in
+++ b/makechrootpkg.in
@@ -144,7 +144,7 @@ delete_chroot() {
 	local copy=${1:-$2}
 
 	stat_busy "Removing chroot copy [%s]" "$copy"
-	if is_btrfs "$chrootdir" && ! mountpoint -q "$copydir"; then
+	if is_subvolume "$copydir" && ! mountpoint -q "$copydir"; then
 		subvolume_delete_recursive "$copydir" ||
 			die "Unable to delete subvolume %s" "$copydir"
 	else