Add a tear-down script for devices used in ART target testing.

This script is meant to undo (most of) the set-up work done by
tools/setup-buildbot-device.sh.

Test: art/tools/setup-buildbot-device.sh && art/tools/teardown-buildbot-device.sh
Bug: 34729697
Change-Id: I4a16d8451f5be461121ca9492dd5e732177bd719

3 files changed, 74 insertions, 5 deletions

diff --git a/tools/cleanup-buildbot-device.sh b/tools/cleanup-buildbot-device.sh
index 8c28828261..2144b02c2f 100755
--- a/tools/cleanup-buildbot-device.sh
+++ b/tools/cleanup-buildbot-device.sh
@@ -40,10 +40,6 @@ if [[ -n "$ART_TEST_CHROOT" ]]; then
   #
   # TODO: Reorder ART Buildbot steps so that "device cleanup" happens
   # before "setup device" and remove this special case.
-  #
-  # TODO: Also consider adding a "tear down device" step on the ART
-  # Buildbot (at the very end of a build) undoing (some of) the work
-  # done in the "device setup" step.
   adb shell test -f "$ART_TEST_CHROOT/system" \
     "&&" find "$ART_TEST_CHROOT/system" \
       ! -path "$ART_TEST_CHROOT/system/etc/selinux/plat_property_contexts" \
diff --git a/tools/setup-buildbot-device.sh b/tools/setup-buildbot-device.sh
index f71d973925..f89197580d 100755
--- a/tools/setup-buildbot-device.sh
+++ b/tools/setup-buildbot-device.sh
@@ -14,10 +14,13 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# The work does by this script is (mostly) undone by tools/teardown-buildbot-device.sh.
+# Make sure to keep these files in sync.
+
 green='\033[0;32m'
 nc='\033[0m'
 
-# Setup as root, as some actions performed here (e.g. setting the date) requires it.
+# Setup as root, as some actions performed here require it.
 adb root
 adb wait-for-device
 
diff --git a/tools/teardown-buildbot-device.sh b/tools/teardown-buildbot-device.sh
new file mode 100755
index 0000000000..df239a28bc
--- /dev/null
+++ b/tools/teardown-buildbot-device.sh
@@ -0,0 +1,70 @@
+#!/bin/bash
+#
+# Copyright (C) 2018 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This script undoes (most of) the work done by tools/setup-buildbot-device.sh.
+# Make sure to keep these files in sync.
+
+green='\033[0;32m'
+nc='\033[0m'
+
+# Setup as root, as some actions performed here require it.
+adb root
+adb wait-for-device
+
+if [[ -n "$ART_TEST_CHROOT" ]]; then
+  # Tear down the chroot dir.
+  echo -e "${green}Tear down the chroot dir in $ART_TEST_CHROOT${nc}"
+
+  # Check that ART_TEST_CHROOT is correctly defined.
+  [[ "x$ART_TEST_CHROOT" = x/* ]] || { echo "$ART_TEST_CHROOT is not an absolute path"; exit 1; }
+
+  # Remove /dev from chroot.
+  adb shell mount | grep -q "^tmpfs on $ART_TEST_CHROOT/dev type tmpfs " \
+    && adb shell umount "$ART_TEST_CHROOT/dev" \
+    && adb shell rmdir "$ART_TEST_CHROOT/dev"
+
+  # Remove /sys/kernel/debug from chroot.
+  adb shell mount | grep -q "^debugfs on $ART_TEST_CHROOT/sys/kernel/debug type debugfs " \
+    && adb shell umount "$ART_TEST_CHROOT/sys/kernel/debug"
+  # Remove /sys from chroot.
+  adb shell mount | grep -q "^sysfs on $ART_TEST_CHROOT/sys type sysfs " \
+    && adb shell umount "$ART_TEST_CHROOT/sys" \
+    && adb shell rmdir "$ART_TEST_CHROOT/sys"
+
+  # Remove /proc from chroot.
+  adb shell mount | grep -q "^proc on $ART_TEST_CHROOT/proc type proc " \
+    && adb shell umount "$ART_TEST_CHROOT/proc" \
+    && adb shell rmdir "$ART_TEST_CHROOT/proc"
+
+  # Remove /etc from chroot.
+  adb shell rm -f "$ART_TEST_CHROOT/etc"
+  adb shell rm -rf "$ART_TEST_CHROOT/system/etc"
+
+  # Remove directories used for ART testing in chroot.
+  adb shell rm -rf "$ART_TEST_CHROOT/data/local/tmp"
+  adb shell rm -rf "$ART_TEST_CHROOT/data/dalvik-cache"
+  adb shell rm -rf "$ART_TEST_CHROOT/tmp"
+
+  # Remove property_contexts file(s) from chroot.
+  property_context_files="/property_contexts \
+    /system/etc/selinux/plat_property_contexts \
+    /vendor/etc/selinux/nonplat_property_context \
+    /plat_property_contexts \
+    /nonplat_property_contexts"
+  for f in $property_context_files; do
+    adb shell test -f "$f" "&&" rm -f "$ART_TEST_CHROOT$f"
+  done
+fi