Update keystone_install.sh for 10.8, avoiding cfprefsd when reading from Info.plist files

chrome/installer/mac/keystone_install.sh

Index: chrome/installer/mac/keystone_install.sh
diff --git a/chrome/installer/mac/keystone_install.sh b/chrome/installer/mac/keystone_install.sh
index 4dca1e2a4f1da44ec7116589212b308dc232ed63..6f038ba321b1101dae5962f0833f8336f1064f43 100755
--- a/chrome/installer/mac/keystone_install.sh
+++ b/chrome/installer/mac/keystone_install.sh
@@ -388,6 +388,39 @@ ksadmin_supports_versionpath_versionkey() {
   # return value.
 }
 
+# Runs "defaults read" to obtain the value of a key in a property list. As
+# with "defaults read", an absolute path to a plist is supplied, without the
+# ".plist" extension.
+#
+# As of Mac OS X 10.8, defaults (and NSUserDefaults and CFPreferences)
+# normally communicates with cfprefsd to read and write plists. Changes to a
+# plist file aren't necessarily reflected immediately via this API family when
+# not made through this API family, because cfprefsd may return cached data
+# from a former on-disk version of a plist file instead of reading the current
+# version from disk. The old behavior can be restored by setting the
+# __CFPREFERENCES_AVOID_DAEMON environment variable, although extreme care
+# should be used because portions of the system that use this API family
+# normally and thus use cfprefsd and its cache will become unsynchronized with
+# the on-disk state.
+#
+# This function is provided to set __CFPREFERENCES_AVOID_DAEMON when calling
+# "defaults read" and thus avoid cfprefsd and its on-disk cache, and is
+# intended only to be used to read values from Info.plist files, which are not
+# preferences. The use of "defaults" for this purpose has always been
+# questionable, but there's no better option to interact with plists from
+# shell scripts. Definitely don't use infoplist_read to read preference
+# plists.
+#
+# This function exists because the update process delivers new copies of
+# Info.plist files to the disk behind cfprefsd's back, and if cfprefsd becomes
+# aware of the original version of the file for any reason (such as this
+# script reading values from it via "defaults read"), the new version of the
+# file will not be immediately effective or visible via cfprefsd after the
+# update is applied.
+infoplist_read() {
+  __CFPREFERENCES_AVOID_DAEMON=1 defaults read "${@}"
+}
+
 usage() {
   echo "usage: ${ME} update_dmg_mount_point" >& 2
 }
@@ -538,8 +571,8 @@ main() {
 
     local update_app_plist="${update_app}/${APP_PLIST}"
     note "update_app_plist = ${update_app_plist}"
-    if ! update_version_app="$(defaults read "${update_app_plist}" \
-                                             "${APP_VERSION_KEY}")" ||
+    if ! update_version_app="$(infoplist_read "${update_app_plist}" \
+                                              "${APP_VERSION_KEY}")" ||
        [[ -z "${update_version_app}" ]]; then
       err "couldn't determine update_version_app"
       exit 2
@@ -548,16 +581,16 @@ main() {
 
     local update_ks_plist="${update_app_plist}"
     note "update_ks_plist = ${update_ks_plist}"
-    if ! update_version_ks="$(defaults read "${update_ks_plist}" \
-                                            "${KS_VERSION_KEY}")" ||
+    if ! update_version_ks="$(infoplist_read "${update_ks_plist}" \
+                                             "${KS_VERSION_KEY}")" ||
        [[ -z "${update_version_ks}" ]]; then
       err "couldn't determine update_version_ks"
       exit 2
     fi
     note "update_version_ks = ${update_version_ks}"
 
-    if ! product_id="$(defaults read "${update_ks_plist}" \
-                                     "${KS_PRODUCT_KEY}")" ||
+    if ! product_id="$(infoplist_read "${update_ks_plist}" \
+                                      "${KS_PRODUCT_KEY}")" ||
        [[ -z "${product_id}" ]]; then
       err "couldn't determine product_id"
       exit 2
@@ -692,8 +725,8 @@ main() {
   local installed_app_plist_path="${installed_app_plist}.plist"
   note "installed_app_plist_path = ${installed_app_plist_path}"
   local old_version_app
-  old_version_app="$(defaults read "${installed_app_plist}" \
-                                   "${APP_VERSION_KEY}" || true)"
+  old_version_app="$(infoplist_read "${installed_app_plist}" \
+                                    "${APP_VERSION_KEY}" || true)"
   note "old_version_app = ${old_version_app}"
 
   # old_version_app is not required, because it won't be present in skeleton
@@ -728,8 +761,8 @@ main() {
   local old_ks_plist="${installed_app_plist}"
   note "old_ks_plist = ${old_ks_plist}"
   local old_brand
-  old_brand="$(defaults read "${old_ks_plist}" \
-                             "${KS_BRAND_KEY}" 2> /dev/null ||
+  old_brand="$(infoplist_read "${old_ks_plist}" \
+                              "${KS_BRAND_KEY}" 2> /dev/null ||
                true)"
   note "old_brand = ${old_brand}"
 
@@ -923,8 +956,8 @@ main() {
   note "reading new values"
 
   local new_version_app
-  if ! new_version_app="$(defaults read "${installed_app_plist}" \
-                                        "${APP_VERSION_KEY}")" ||
+  if ! new_version_app="$(infoplist_read "${installed_app_plist}" \
+                                         "${APP_VERSION_KEY}")" ||
      [[ -z "${new_version_app}" ]]; then
     err "couldn't determine new_version_app"
     exit 9
@@ -938,8 +971,8 @@ main() {
   note "new_ks_plist = ${new_ks_plist}"
 
   local new_version_ks
-  if ! new_version_ks="$(defaults read "${new_ks_plist}" \
-                                       "${KS_VERSION_KEY}")" ||
+  if ! new_version_ks="$(infoplist_read "${new_ks_plist}" \
+                                        "${KS_VERSION_KEY}")" ||
      [[ -z "${new_version_ks}" ]]; then
     err "couldn't determine new_version_ks"
     exit 9
@@ -947,7 +980,7 @@ main() {
   note "new_version_ks = ${new_version_ks}"
 
   local update_url
-  if ! update_url="$(defaults read "${new_ks_plist}" "${KS_URL_KEY}")" ||
+  if ! update_url="$(infoplist_read "${new_ks_plist}" "${KS_URL_KEY}")" ||
      [[ -z "${update_url}" ]]; then
     err "couldn't determine update_url"
     exit 9
@@ -957,8 +990,8 @@ main() {
   # The channel ID is optional.  Suppress stderr to prevent Keystone from
   # seeing possible error output.
   local channel
-  channel="$(defaults read "${new_ks_plist}" "${KS_CHANNEL_KEY}" 2> /dev/null ||
-             true)"
+  channel="$(infoplist_read "${new_ks_plist}" \
+                            "${KS_CHANNEL_KEY}" 2> /dev/null || true)"
   note "channel = ${channel}"
 
   # Make sure that the update was successful by comparing the version found in
@@ -1291,8 +1324,8 @@ main() {
 
   if [[ -z "${system_ticket}" ]]; then
     local new_bundleid_app
-    new_bundleid_app="$(defaults read "${installed_app_plist}" \
-                                      "${APP_BUNDLEID_KEY}" || true)"
+    new_bundleid_app="$(infoplist_read "${installed_app_plist}" \
+                                       "${APP_BUNDLEID_KEY}" || true)"
     note "new_bundleid_app = ${new_bundleid_app}"
 
     local keychain_reauthorize_dir="\