Cleans up image_to_live changes and handles errors more gracefully

src/scripts/image_to_live.sh

 #!/bin/bash
 
 # Copyright (c) 2009 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # Script to update an image onto a live running ChromiumOS instance.
 
 # Load common constants.  This should be the first executable line.
 # The path to common.sh should be relative to your script's location.
@@ skipping 13 matching lines @@
 function kill_all_devservers {
   # Using ! here to avoid exiting with set -e is insufficient, so use
   # || true instead.
   pkill -fx ".*devserver\.py" || true
 }
 
 function cleanup {
   echo "Killing dev server."
   kill_all_devservers
   cleanup_remote_access
+  rm -rf "${TMP}"
+}
+
+function unmount_gpt {
   ./mount_gpt_image.sh -mu
-  rm -rf "${TMP}"
 }
 
 function remote_reboot_sh {
   rm -f "${TMP_KNOWN_HOSTS}"
   remote_sh "$@"
 }
 
 function start_dev_server {
   kill_all_devservers
   if [ ${FLAGS_verbose} -eq ${FLAGS_FALSE} ]; then
     ./enter_chroot.sh "./start_devserver > /dev/null 2>&1" &
   else
     ./enter_chroot.sh "./start_devserver" &
   fi
   echo -n "Waiting on devserver to start"
   until netstat -anp 2>&1 | grep 8080 > /dev/null; do
     sleep .5
     echo -n "."
   done
   echo ""
 }
 
+# Copys new stateful var and developer directories to updating system.
+# chromeos_startup checks for .update_available on next boot and updates
+# the stateful directories.
 function copy_stateful_tarball {
   echo "Starting stateful update."
   # Mounts most recent image stateful dir to /tmp/s
   ./mount_gpt_image.sh -m
+  trap "unmount_gpt && cleanup" EXIT
+
   # Create tar files for the stateful partition.
-  cd /tmp/s/var && sudo tar -cf /tmp/var.tar . && cd -
-  cd /tmp/s/dev_image && sudo tar -cf /tmp/developer.tar . && cd -
-  # Copy over tar files.
-  remote_cp /tmp/var.tar /tmp
-  remote_cp /tmp/developer.tar /tmp
-  remote_sh "mkdir /mnt/stateful_partition/var_new &&\
-             mkdir /mnt/stateful_partition/dev_image_new &&\
-             tar -xf /tmp/var.tar -C /mnt/stateful_partition/var_new &&\
-             tar -xf /tmp/developer.tar \
-               -C /mnt/stateful_partition/dev_image_new &&\
-             touch /mnt/stateful_partition/.update_available"
+  if [ ! -d /tmp/s/var ] || [ ! -d /tmp/s/dev_image ] ; then
+    echo "No stateful directories found to copy.  Continuing update."
+  else
+    pushd /tmp/s/var && sudo tar -czf /tmp/var.tgz . && popd
+    pushd /tmp/s/dev_image && sudo tar -czf /tmp/developer.tgz . && popd
+    # Copy over tar files.
+    local s_dir="/mnt/stateful_partition"
+    remote_cp /tmp/var.tgz /tmp
+    remote_cp /tmp/developer.tgz /tmp
+    remote_sh "rm -rf $s_dir/var_new $s_dir/dev_image_new &&\
+               mkdir $s_dir/var_new $s_dir/dev_image_new &&\
+               tar -xzf /tmp/var.tgz -C $s_dir/var_new &&\
+               tar -xzf /tmp/developer.tgz -C $s_dir/dev_image_new &&\
+               touch $s_dir/.update_available"
+  fi
   # unmounts stateful partition
   ./mount_gpt_image.sh -mu
+
+  trap cleanup EXIT
 }
 
 function prepare_update_metadata {
   remote_sh "mount -norw,remount /"
 
   if [[ ${FLAGS_ignore_version} -eq ${FLAGS_TRUE} ]]; then
     echo "Forcing update independent of the current version"
     remote_sh "cat /etc/lsb-release |\
         grep -v CHROMEOS_RELEASE_VERSION > /etc/lsb-release~;\
         mv /etc/lsb-release~ /etc/lsb-release; \
@@ skipping 109 matching lines @@
 
   prepare_update_metadata
 
   if ! run_auto_update; then
     echo "Update was not successful."
     exit 1
   fi
 
   if ! copy_stateful_tarball; then
     echo "Stateful update was not successful."
-    exit 1
   fi
 
   remote_reboot
 
   if [[ ${FLAGS_update_hostkey} -eq ${FLAGS_TRUE} ]]; then
     local known_hosts="${HOME}/.ssh/known_hosts"
     cp "${known_hosts}" "${known_hosts}~"
     grep -v "^${FLAGS_remote} " "${known_hosts}" > "${TMP}/new_known_hosts"
     cat "${TMP}/new_known_hosts" "${TMP_KNOWN_HOSTS}" > "${known_hosts}"
     chmod 0640 "${known_hosts}"
     echo "New updated in ${known_hosts}, backup made."
   fi
 
   remote_sh "grep ^CHROMEOS_RELEASE_DESCRIPTION= /etc/lsb-release"
   local release_description=$(echo $REMOTE_OUT | cut -d '=' -f 2)
   echo "Update was successful and rebooted to $release_description"
 
   return 0
 }
 
 main $@