Add "--mount" option to package_to_live

bin/cros_package_to_live

 #!/bin/bash
 
 # Copyright (c) 2010 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 a running device with an optionally built package out
 # of your build directory
 
 # Load common constants.  This should be the first executable line.
@@ skipping 15 matching lines @@
 DEFINE_string board "$DEFAULT_BOARD" \
     "Board for which the package should be built/found"
 DEFINE_string build_root "/build" \
     "The root location for board sysroots."
 
 FLAGS "$@" || exit 1
 
 TMP=$(mktemp -d /tmp/cros_package_to_live.XXXX)
 
 function cleanup {
-  cleanup_remote_access
-  rm -rf "${TMP}"
+    if [ "${mount_type}" = ro ]; then
+        remote_sh "mount -o remount,ro /" || /bin/true
+    fi
+    cleanup_remote_access
+    rm -rf "${TMP}"
 }
 
 # Make sure we have a package name
 if [ -z "${FLAGS_ARGV}" ]; then
     echo "Please specify packages to install.  For example:"
     echo "  $0 --remote=MyMachine flimflam"
     exit 1
 fi
 
 if [ -z "${FLAGS_board}" ]; then
     echo "Please specify a board using the --board=MyBoard argument"
     exit 1
 fi
 
 set -e
 trap cleanup EXIT
 
 remote_access_init
 
 eval set -- "${FLAGS_ARGV}"
 
 if [ ${FLAGS_build} -eq ${FLAGS_TRUE} ]; then
     emerge-${FLAGS_board} $@
 fi
 
 PKGROOT="${FLAGS_build_root}/${FLAGS_board}/packages"
 
+remote_sh "grep '\S* / ' /proc/mounts | tail -1 | awk '{ print \$4 }' |
+           cut -d, -f1"
+mount_type=$REMOTE_OUT
+if [ "${mount_type}" = ro ]; then
+    remote_sh "mount -o remount,rw /"
+fi
+
 for pkg in $@; do
     latest_pkg=$(ls -tr $PKGROOT/*/${pkg}-[0-9]* | tail -1)
     if [ -z "${latest_pkg}" ]; then
         echo "Could not find latest built version of ${pkg}"
         exit 1
     fi
     pkg_dir=$(basename $(dirname $latest_pkg))
     pkg_name=$(basename $latest_pkg)
     echo "Installing ${latest_pkg}..."
 
     remote_sh "mktemp -d /tmp/cros_package_to_live.XXXX"
     temp_dir=$REMOTE_OUT
     remote_cp_to "${latest_pkg}" "${temp_dir}"
-    remote_sh "mount -o remount,rw /"
     remote_sh "mkdir -p /usr/portage/packages/${pkg_dir} &&
                mv ${temp_dir}/${pkg_name} /usr/portage/packages/${pkg_dir} &&
                env FEATURES=-sandbox emerge --usepkg \
                     /usr/portage/packages/${pkg_dir}/${pkg_name} 1>&2"
     echo "${pkg} has been installed"
     remote_sh "rm -rf ${temp_dir}"
-    remote_sh "mount -o remount,ro /" || /bin/true
 done