fix motd.sh disks for btrfs

motd.sh

@@ -109,7 +109,7 @@ max_usage=80
 bar_width=50
 
 # disk usage: ignore zfs, squashfs & tmpfs
-DISKS=$(df -H -x squashfs -x tmpfs -x devtmpfs -x zfs --output=target,pcent,size,used | tail -n+2)" 0 0 0 -"
+DISKS=$(df -H -x squashfs -x tmpfs -x devtmpfs -x zfs -x overlay --output=target,pcent,size,used | tail -n+2)" 0 0 0 -"
 
 if test $(command -v zfs); then
 	DISKS+="\n"
@@ -134,19 +134,29 @@ while read line; do
 	fi
     # get disk usage
     dds=$(echo "$line" | awk '{print $6}' | sed 's/%//')
-    dds_width=$((($dds*$bar_width)/100))
-    child=$(echo "$line" | awk '{print $7}' | sed 's/%//')
-    child_width=$((($child*$bar_width)/100))
-    snap=$(echo "$line" | awk '{print $5}' | sed 's/%//')
-    snap_width=$((($snap*$bar_width)/100))
-    usage=$(echo "$line" | awk '{print $2}' | sed 's/%//')
-    used_width=$((($usage*$bar_width)/100))
+    if [ -z "$dds" ]; then
+        dds_width=0
+        child_width=0
+        snap_width=0
+        usage=$(echo "$line" | sed -E "s/.+([0-9]{2,3})%.+/\1/")
+    else
+        dds_width=$((($dds*$bar_width)/100))
 
-	#echo "$line"
+        child=$(echo "$line" | awk '{print $7}' | sed 's/%//')
+        child_width=$((($child*$bar_width)/100))
+
+        snap=$(echo "$line" | awk '{print $5}' | sed 's/%//')
+        snap_width=$((($snap*$bar_width)/100))
+
+        usage=$(echo "$line" | awk '{print $2}' | sed 's/%//')
+    fi
+
+    used_width=$((($usage*$bar_width)/100))
+    #echo "$line"
     #echo "$dds,$dds_width|$child,$child_width|$snap,$snap_width|$usage,$used_width"
 
 	i=0
-    # [
+	# [
     bar="["
 
 	# DDS