[OE-core] [oe-core][dizzy][PATCH] base-files: Check for /run and /var/lock softlinks on upgrade

[Bryan Evenson]

Commit ea647cd9eebdc3e3121b84074519c4bb305adac9 moved the locations
of /run and /var/lock to match the FHS 3 draft specifications.
However, the install doesn't remove the existing directories.
As a result, upgrading a system may result in /run as a softlink
to /var/run and /var/run as a softlink to /run, creating a circular
link.

During pre and post-install, check for the existence of the old
softlinks, move the old file contents to a temporary location, remove
the softlinks, and restore the directory contents after installation.

Signed-off-by: Bryan Evenson <bevenson at melinkcorp.com>
---
 meta/recipes-core/base-files/base-files_3.0.14.bb | 55 +++++++++++++++++++++++
 1 file changed, 55 insertions(+)

diff --git a/meta/recipes-core/base-files/base-files_3.0.14.bb b/meta/recipes-core/base-files/base-files_3.0.14.bb
index 07f5c54..71cea08 100644
--- a/meta/recipes-core/base-files/base-files_3.0.14.bb
+++ b/meta/recipes-core/base-files/base-files_3.0.14.bb
@@ -66,6 +66,41 @@ hostname = "openembedded"
 
 BASEFILESISSUEINSTALL ?= "do_install_basefilesissue"
 
+# In previous versions of base-files, /run was a softlink to /var/run and the
+# directory was located in /var/volatlie/run.  Also, /var/lock was a softlink
+# to /var/volatile/lock which is where the real directory was located.  Now,
+# /run and /run/lock are the real directories.  If we are upgrading, we may
+# need to remove the symbolic links first before we create the directories.
+# Otherwise the directory creation will fail and we will have circular symbolic
+# links.
+# 
+# If we do need to remove the symbolic links first, we also need to preserve
+# all the contents of the directory so running programs can find the files that
+# are in use in these directories.  Move the contents to a temporary directory
+# during pre-install to protect the contents
+pkg_preinst_${PN} () {
+    #!/bin/sh -e
+    if [ x"$D" = "x" ]; then
+        if [ -e "/var/volatile/lock" ]; then
+            # Move the contents of /var/volatile/lock to a temporary directory
+            mkdir -p /run_lock_tmp
+            mv /var/volatile/lock/* /run_lock_tmp/
+
+            # Remove the current directory
+            rm -rf /var/volatile/lock
+        fi
+
+        if [ -h "/run" ]; then
+            # Move the contents of /run to a temporary directory
+            mkdir -p /run_tmp
+            mv /run/* /run_tmp/
+
+            # Remove the current directory
+            rm -rf /run
+        fi
+    fi     
+}
+
 do_install () {
 	for d in ${dirs755}; do
 		install -m 0755 -d ${D}$d
@@ -79,6 +114,7 @@ do_install () {
 	for d in ${volatiles}; do
 		ln -sf volatile/$d ${D}${localstatedir}/$d
 	done
+
 	ln -snf ../run ${D}${localstatedir}/run
 	ln -snf ../run/lock ${D}${localstatedir}/lock
 
@@ -144,6 +180,25 @@ do_install_append_linuxstdbase() {
         done
 }
 
+# If we are on the actual hardware, check if we had to move /run and /run/lock.
+# If so, copy the temporary directory contents to their new locations.
+pkg_postinst_${PN} () {
+    #!/bin/sh -e
+    if [ x"$D" = "x" ]; then
+        if [ -e "/run_tmp" ]; then
+            mv /run_tmp/* /run/
+            rmdir /run_tmp
+        fi
+
+        if [ -e "/run_lock_tmp/" ]; then
+            mv /run_lock_tmp/* /run/lock
+            rmdir /run_lock_tmp
+        fi
+    else
+        exit 1
+    fi     
+}
+
 PACKAGES = "${PN}-doc ${PN} ${PN}-dev ${PN}-dbg"
 FILES_${PN} = "/"
 FILES_${PN}-doc = "${docdir} ${datadir}/common-licenses"
-- 
2.1.0