tree c527b4d1c394beaff2a01df70c1f97bd24eead39
parent 3275606278533a27f61263e39718acc8d77afebb
author Alex Deymo <deymo@google.com> 1457142782 -0800
committer Alex Deymo <deymo@google.com> 1458250747 -0700

Rework postinstall unittests to pass on Android.

Postinstall unittests were creating and mounting an image on each test
run. This patch adds several test scripts to one of the pre-generated
images and uses that image during postinstall testing instead.

To workaround problems with mount/umount of loop devices on Android,
this patch rewrites the `losetup` logic to make the appropriate
syscalls and create the loop device with mknod if it doesn't exists.

The tests require some extra SELinux policies to run in enforcing mode.

Bug: 26955860
TEST=Ran all Postinstall unittests.

(cherry picked from commit cbc2274c4160805bf726df872390112654816ca7)

Change-Id: Ib4644572e2813615c89e4c6eef632e895cf0b90c