ejection script for cdrom duplication

included some necessary dependencies

1 files changed, 47 insertions, 0 deletions

diff --git a/samizdat-eject.sh b/samizdat-eject.sh
new file mode 100755
index 0000000..04ee610
--- /dev/null
+++ b/samizdat-eject.sh
@@ -0,0 +1,47 @@
+#!/bin/sh
+
+. mdadm-dup.sh || exit 1
+
+btrfs_subdevices()
+{
+    local mountpoint="$1"
+    btrfs filesystem show "$mountpoint" | sed -ne 's/^[ \t]*devid.* path //p'
+}
+
+devices=$(btrfs_subdevices /) || exit 1
+
+set --
+seen=
+for dev in $devices; do
+    [ -b "$dev" ] || exit 1
+    case "$dev" in
+        /dev/mapper/loop*) set -- "$@" "$dev" ;;
+        /dev/mapper/samizdatcrypt) seen=y ;;
+    esac
+done
+[ "$seen" ] || exit 1
+
+copy()
+{
+    mdadm_copy_eject /dev/md55 /root/samizdat.iso
+}
+
+remove()
+{
+    for dev; do
+        (set -x; btrfs device remove "$dev" /)
+    done
+}
+
+# Doing the mdadm copy before removing the devices means our filesystem includes
+# devices that are ultimately backed by files ON THE SAME FILESYSTEM. As such, it
+# might conceivably put btrfs into a deadlock of some kind.
+
+# If it turns out this doesn't work, the order can be reversed. This will
+# perform the read IO twice, though, almost doubling the total installation
+# time.
+
+copy & remove "$@"
+
+set -x
+wait