fix build issues with lua version higher than 5.1

refer to https://bugs.gentoo.org/963055

I´ve been asked to pass this upstream

diff --git a/src/libstat/backends/redis_backend.cxx b/src/libstat/backends/redis_backend.cxx
index 3a78de1dde2161ab69a511839ab75029fc94043b..37ce6e9da7a0b102387e70e64e39fc7f2cf7dba0 100644 (file)
--- a/src/libstat/backends/redis_backend.cxx
+++ b/src/libstat/backends/redis_backend.cxx
@@ -15,6 +15,9 @@
  */
 #include "config.h"
 #include "lua/lua_common.h"
+#if LUA_VERSION_NUM >= 502
+#  define lua_objlen lua_rawlen
+#endif
 #include "rspamd.h"
 #include "stat_internal.h"
 #include "upstream.h"