diff --git a/hosts/common/optional/btrfs-impermanence.nix b/hosts/common/optional/btrfs-impermanence.nix new file mode 100644 index 0000000..9e7fb46 --- /dev/null +++ b/hosts/common/optional/btrfs-impermanence.nix @@ -0,0 +1,26 @@ +{ +boot.initrd.postDeviceCommands = lib.mkAfter '' + mkdir /btrfs_tmp + mount / /btrfs_tmp + if [[ -e /btrfs_tmp/root ]]; then + mkdir -p /btrfs_tmp/old_roots + timestamp=$(date --date="@$(stat -c %Y /btrfs_tmp)" "+%Y-%m-%-d_%H:%M:%S") + mv /btrfs_tmp "/btrfs_tmp/old_roots/$timestamp" + fi + + delete_subvolume_recursively() { + IFS=$'\n' + for i in $(btrfs subvolume list -o "$1" | cut -f 9- -d ' '); do + delete_subvolume_recursively "/btrfs_tmp/$i" + done + btrfs subvolume delete "$1" + } + + for i in $(find /btrfs_tmp/old_roots/ -maxdepth 1 -mtime +30); do + delete_subvolume_recursively "$i" + done + + btrfs subvolume create /btrfs_tmp/root + umount /btrfs_tmp + ''; +}