lib: Load built-in Lua functions

We can't use even `string()` function because built-in functions are not
loaded.

Testing with:

```
$ cat /etc/frr/scripts/zebra.lua
function on_rib_process_dplane_results(ctx)
	log.warn(string.upper("testas"))
	return {}
end
```

This results to "TESTAS" in the logs.

Signed-off-by: Donatas Abraitis <donatas@opensourcerouting.org>

diff --git a/lib/frrscript.c b/lib/frrscript.c
index acdd1df67b4d0d0b4d09ad26cf7729f911811772..dbae31b66685b4e11e18a1c798403b4ead814692 100644 (file)
--- a/lib/frrscript.c
+++ b/lib/frrscript.c
@@ -348,6 +348,9 @@ int frrscript_load(struct frrscript *fs, const char *function_name,
        /* Set up the Lua script */
        lua_State *L = luaL_newstate();
 
+       /* Load basic built-in Lua functions, e.g. ipairs, string, etc. */
+       luaL_openlibs(L);
+
        frrlua_export_logging(L);
 
        char script_name[MAXPATHLEN];