updated btrfs send/recv code; script to put layered seed on iso

1 files changed, 33 insertions, 9 deletions

diff --git a/btrfs-functions.sh b/btrfs-functions.sh
index 3648c24..b83b94d 100644
--- a/btrfs-functions.sh
+++ b/btrfs-functions.sh
@@ -100,28 +100,52 @@ btrfs_show_default_path()
     mp=$(btrfs_get_mountpoint "$mp") || die # TODO: fix caller?
     btrfs_mountpoint "$mp" || die "not a mountpoint: $mp"
     path=$(btrfs subvolume get-default "$mp"/|sed -n -e 's/.* path //p')
-    printf '%s\n' "$mp/$path"
+    if [ "$path" ]; then
+        printf '%s\n' "$mp/$path"
+    else
+        printf '%s\n' "$mp"
+    fi
+}
+
+btrfs_show_default_id()
+{
+    $(ARGS_NE mp)
+    local id
+    mp=$(btrfs_get_mountpoint "$mp") || die # TODO: fix caller?
+    btrfs_mountpoint "$mp" || die "not a mountpoint: $mp"
+    id=$(btrfs subvolume get-default "$mp"/|sed -n -e 's/^ID \([^ ]*\) .*/\1/p')
+    [ "$id" ] || return
+    echo $id
 }
 
 btrfs_replace_default_subvolume_with()
 {
     $(ARGS_NE new_default)
-    local old_default subvol_id
-    old_default=$(btrfs_show_default_path "$new_default") || die
+    local old_default old_default_id new_default_id
+    old_default_id=$(btrfs_show_default_id "$new_default")       || die
+    new_default_id=$(btrfs_show_subvolume_id "$new_default")     || die
+
+    [ "$new_default_id" = "$old_default_id" ] && return
+
+    if [ "$old_default_id" != 5 ]; then
+        old_default=$(btrfs_show_default_path "$new_default")    || die
+    else
+        old_default=
+    fi
 
-    [ "$new_default" = "$old_default" ] && return
+    btrfs subvolume set-default "$new_default_id" "$new_default" || die
 
-    subvol_id=$(btrfs_show_subvolume_id "$new_default")       || die
-    btrfs subvolume set-default "$subvol_id" "$new_default" || die
-    btrfs subvolume delete "$old_default"
-    sex mv "$new_default" "$old_default"
+    if [ "$old_default" ]; then
+        btrfs subvolume delete "$old_default"
+        sex mv "$new_default" "$old_default"
+    fi
 }
 
 btrfs_show_subvolume_id()
 {
     $(ARGS_NE path)
     local result
-    result=$(btrfs subvolume show "$path" | sed -n -e 's/^[ \t]*Subvolume ID:[ \t]*//p')
+    result=$(btrfs subvolume show "$path" | sed -n -e 's/^[ \t]*Subvolume ID:[ \t]*//p; s/.*is toplevel subvolume/5/p')
     if [ "$result" ]
     then printf '%s\n' "$result"
     else false