diff --git a/include/types/hlua.h b/include/types/hlua.h
index d1aa235..85d7e81 100644
--- a/include/types/hlua.h
+++ b/include/types/hlua.h
@@ -3,4 +3,31 @@
 
 #include <lua.h>
 
+enum hlua_state {
+	HLUA_STOP = 0,
+	HLUA_RUN,
+};
+
+enum hlua_exec {
+	HLUA_E_OK = 0,
+	HLUA_E_AGAIN,  /* LUA yield, must resume the stack execution later, when
+	                  the associatedtask is waked. */
+	HLUA_E_ERRMSG, /* LUA stack execution failed with a string error message
+	                  in the top of stack. */
+	HLUA_E_ERR,    /* LUA stack execution failed without error message. */
+};
+
+struct hlua {
+	lua_State *T; /* The LUA stack. */
+	int Tref; /* The reference of the stack in coroutine case.
+	             -1 for the main lua stack. */
+	int Mref; /* The reference of the memory context in coroutine case.
+	             -1 if the memory context is not used. */
+	int nargs; /* The number of arguments in the stack at the start of execution. */
+	enum hlua_state state; /* The current execution state. */
+	struct task *task; /* The task associated with the lua stack execution.
+	                      We must wake this task to continue the task execution */
+	struct ebpt_node node;
+};
+
 #endif /* _TYPES_HLUA_H */