installer: fix the "umount: XXX not mounted" error message during postinst

chromeos-setimage

Index: chromeos-setimage
diff --git a/chromeos-setimage b/chromeos-setimage
index d1be3321a64ccc6f4ffdede1fba95268a1ac3457..dbaadc399692572659aeb01419ec4d8fc32179c1 100755
--- a/chromeos-setimage
+++ b/chromeos-setimage
@@ -115,19 +115,23 @@ KERN_LOOP=
 
 cleanup_loop() {
   local dev="$1"
+  local cleanup_command="$2"
   if [ -z "$dev" ]; then
     return 0
   fi
-  (sudo umount "$dev" || true)
+  if [ -n "$cleanup_command" ]; then
+    (sudo "$cleanup_command" "$dev" || true)
+  fi
   (sudo losetup -d "$dev" || true)
 }
 
 cleanup() {
-  cleanup_loop "${ESP_LOOP}"
+  # Currently only ESP may be mounted. KERN and ROOT are never mounted.
+  cleanup_loop "${ESP_LOOP}" "umount"
   ESP_LOOP=
-  cleanup_loop "${KERN_LOOP}"
+  cleanup_loop "${KERN_LOOP}" ""

[Will Drewry, 2010/11/18 09:20:15]

Do you need to specify empty $2s here?

[Hung-Te, 2010/11/18 09:49:02]

Although it may be not necessary, I think an explicit "" may help letting
developer to know "you have to pass something here"

   KERN_LOOP=
-  cleanup_loop "${ROOT_LOOP}"
+  cleanup_loop "${ROOT_LOOP}" ""
   ROOT_LOOP=
 
   # Failing to clean this up isn't the worst.