numerous updates

updates.d/09-snapshot.sh

@@ -0,0 +1,15 @@
+#!/bin/bash
+
+# Snapshot / before the system update so a bad upgrade can be rolled back.
+# system/snapper.sh creates the "root" config on btrfs machines and keeps the
+# last 5 snapshots.
+
+is_installed() {
+  command -v snapper &>/dev/null && [ -f /etc/snapper/configs/root ]
+}
+
+run_update() {
+  echo "Snapshotting / before updating..."
+  sudo snapper -c root create -c number -d "Before CoreDesktop update" \
+    && sudo snapper -c root cleanup number
+}