[Minor] Lua_ip: Add address comparison method

src/lua/lua_ip.c

@@ -165,6 +165,13 @@ LUA_FUNCTION_DEF (ip, get_port);
  */
 LUA_FUNCTION_DEF (ip, is_local);
 
+/***
+ * @method ip:less_than(other)
+ * Returns true if address is less than other
+ * @return {boolean}
+ */
+LUA_FUNCTION_DEF (ip, less_than);
+
 static const struct luaL_reg iplib_m[] = {
 	LUA_INTERFACE_DEF (ip, to_string),
 	LUA_INTERFACE_DEF (ip, to_table),
@@ -183,6 +190,7 @@ static const struct luaL_reg iplib_m[] = {
 	{"__tostring", lua_ip_to_string},
 	{"__eq", lua_ip_equal},
 	{"__gc", lua_ip_destroy},
+	{"__lt", lua_ip_less_than},
 	{NULL, NULL}
 };
 
@@ -557,6 +565,24 @@ lua_ip_is_local (lua_State *L)
 	return 1;
 }
 
+static gint
+lua_ip_less_than (lua_State *L)
+{
+	LUA_TRACE_POINT;
+	struct rspamd_lua_ip *ip = lua_check_ip (L, 1),
+			*other = lua_check_ip (L, 2);
+
+	if (ip && other) {
+		lua_pushboolean (L,
+				rspamd_inet_address_compare (ip->addr, other->addr, true) < 0);
+	}
+	else {
+		lua_pushnil (L);
+	}
+
+	return 1;
+}
+
 void
 rspamd_lua_ip_push (lua_State *L, rspamd_inet_addr_t *addr)
 {