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..162170be369976e52ce91f40e32dd6196964ef9d 100755
--- a/chromeos-setimage
+++ b/chromeos-setimage
@@ -113,21 +113,29 @@ ESP_LOOP=
 ROOT_LOOP=
 KERN_LOOP=
 
+# Cleans up a device and unmount if required.
 cleanup_loop() {
   local dev="$1"
+  local need_umount="$2"
   if [ -z "$dev" ]; then
     return 0
   fi
-  (sudo umount "$dev" || true)
-  (sudo losetup -d "$dev" || true)
+  if [ "$need_umount" = ${FLAGS_TRUE} ]; then

[Will Drewry, 2010/11/23 01:36:50]

nit: FLAGS_TRUE/FALSE is normally checked with -eq and not using a string
equality, though it should be equivalent.

[Hung-Te, 2010/11/23 02:14:52]

Done.

+    sudo umount -d "$dev" || true
+  elif [ "$need_umount" = ${FLAGS_FALSE} ]; then
+    sudo losetup -d "$dev" || true
+  else
+    echo "INTERNAL ERROR: unknown parameter for cleanup_loop: $need_umount" >&2
+  fi
 }
 
 cleanup() {
-  cleanup_loop "${ESP_LOOP}"
+  # Currently only ESP may be mounted. KERN and ROOT are never mounted.
+  cleanup_loop "${ESP_LOOP}" "${FLAGS_TRUE}"
   ESP_LOOP=
-  cleanup_loop "${KERN_LOOP}"
+  cleanup_loop "${KERN_LOOP}" "${FLAGS_FALSE}"
   KERN_LOOP=
-  cleanup_loop "${ROOT_LOOP}"
+  cleanup_loop "${ROOT_LOOP}" "${FLAGS_FALSE}"
   ROOT_LOOP=
 
   # Failing to clean this up isn't the worst.