Bug #13548161: MYSQLD_SAFE IMPROVEMENTS FOR 5.5 ALLWAYS SETS PLUGIN_DIR

TO DEFAULT IGNOR

The test in mysqld_safe for the presence of the --plugin-dir and assigning a default
value to it were performed before the actual argument parsing.
This is wrong, as PLUGIN_DIR mysqld_safe code also uses MY_BASEDIR_VERSION to 
look for version specific plugin directory if present.
Fixed by moving the PLUGIN_DIR logic after the parse_arguments() call.

scripts/mysqld_safe.sh

@@ -413,29 +413,6 @@ else
   DATADIR=@localstatedir@
 fi
 
-#
-# Try to find the plugin directory
-#
-
-# Use user-supplied argument
-if [ -n "${PLUGIN_DIR}" ]; then
-  plugin_dir="${PLUGIN_DIR}"
-else
-  # Try to find plugin dir relative to basedir
-  for dir in lib/mysql/plugin lib/plugin
-  do
-    if [ -d "${MY_BASEDIR_VERSION}/${dir}" ]; then
-      plugin_dir="${MY_BASEDIR_VERSION}/${dir}"
-      break
-    fi
-  done
-  # Give up and use compiled-in default
-  if [ -z "${plugin_dir}" ]; then
-    plugin_dir='@pkgplugindir@'
-  fi
-fi
-plugin_dir="${plugin_dir}${PLUGIN_VARIANT}"
-
 if test -z "$MYSQL_HOME"
 then 
   if test -r "$MY_BASEDIR_VERSION/my.cnf" && test -r "$DATADIR/my.cnf"
@@ -496,6 +473,31 @@ fi
 parse_arguments `$print_defaults $defaults --loose-verbose mysqld_safe safe_mysqld`
 parse_arguments PICK-ARGS-FROM-ARGV "$@"
 
+
+#
+# Try to find the plugin directory
+#
+
+# Use user-supplied argument
+if [ -n "${PLUGIN_DIR}" ]; then
+  plugin_dir="${PLUGIN_DIR}"
+else
+  # Try to find plugin dir relative to basedir
+  for dir in lib/mysql/plugin lib/plugin
+  do
+    if [ -d "${MY_BASEDIR_VERSION}/${dir}" ]; then
+      plugin_dir="${MY_BASEDIR_VERSION}/${dir}"
+      break
+    fi
+  done
+  # Give up and use compiled-in default
+  if [ -z "${plugin_dir}" ]; then
+    plugin_dir='@pkgplugindir@'
+  fi
+fi
+plugin_dir="${plugin_dir}${PLUGIN_VARIANT}"
+
+
 # Determine what logging facility to use
 
 # Ensure that 'logger' exists, if it's requested