update-rc.d: process symlinks recursively

When processing startup scripts which use update-alternatives, we need to keep
resolving the symlink recursively until we hit a real file, due to the
alternatives indirection. This fixes the ability to run certain postinsts at
do_rootfs time, which is needed for good read-only-rootfs support.

(From OE-Core rev: 987a203f85e9474fd1807e577c7fd8c30ecf78d6)

Signed-off-by: Christopher Larson <kergoth@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 16 insertions, 10 deletions

diff --git a/meta/recipes-core/update-rc.d/update-rc.d/check-if-symlinks-are-valid.patch b/meta/recipes-core/update-rc.d/update-rc.d/check-if-symlinks-are-valid.patch
index 6f402ddb6d..075171a5a3 100644
--- a/meta/recipes-core/update-rc.d/update-rc.d/check-if-symlinks-are-valid.patch
+++ b/meta/recipes-core/update-rc.d/update-rc.d/check-if-symlinks-are-valid.patch
@@ -14,25 +14,31 @@ actually exists in rootfs path and then continue.
 Upstream-Status: Pending
 
 Signed-off-by: Laurentiu Palcu <laurentiu.palcu@intel.com> 
+Signed-off-by: Christopher Larson <chris_larson@mentor.com>
 
 Index: git/update-rc.d
 ===================================================================
---- git.orig/update-rc.d        2013-01-16 12:12:58.349814356 +0200
-+++ git/update-rc.d     2013-01-16 13:02:42.490864939 +0200
-@@ -147,13 +147,29 @@
+--- git.orig/update-rc.d
++++ git/update-rc.d
+@@ -147,13 +147,34 @@ fi
  bn=$1
  shift
  
 +sn=$initd/$bn
 +if [ -L "$sn" -a -n "$root" ]; then
-+       readlink=$(which readlink)
++       if which readlink >/dev/null; then
++               while true; do
++                       linksn="$(readlink "$sn")"
++                       if [ -z "$linksn" ]; then
++                               break
++                       fi
 +
-+       if [ -n "$readlink" ]; then
-+               sn=$($readlink "$sn")
-+               case "$sn" in
-+                       /*) sn=${root}${sn} ;;
-+                       *)  sn=$initd/$sn ;;
-+               esac
++                       sn="$linksn"
++                       case "$sn" in
++                               /*) sn="$root$sn" ;;
++                               *)  sn="$initd/$sn" ;;
++                       esac
++               done
 +       else
 +               echo "update-rc.d: readlink tool not present, cannot check whether \
 +                               $sn symlink points to a valid file." >&2