[PATCH 1/1] box: expose on_commit/rollback triggers for Lua

[Vladimir Davydov]

On Thu, Aug 16, 2018 at 08:57:10PM +0300, Vladislav Shpilevoy wrote:
> +/**
> + * Update the transaction on_commit/rollback triggers.
> + * @sa lbox_trigger_reset.
> + */
> +#define lbox_on_txn_end(name) do {                                             \
> +	struct txn *txn = in_txn();                                            \
> +	int top = lua_gettop(L);                                               \
> +	if (top > 2 || txn == NULL) {                                          \
> +		return luaL_error(L, "Usage inside a transaction: "            \
> +				  "box.on_" #name "([function | nil, "         \
> +				  "[function | nil]])");                       \
> +	}                                                                      \
> +	txn_init_triggers(txn);                                                \
> +	return lbox_trigger_reset(L, 2, &txn->on_##name, lbox_push_txn, NULL); \
> +} while (0)
> +
> +static int
> +lbox_on_commit(struct lua_State *L)
> +{
> +	lbox_on_txn_end(commit);
> +}
> +
> +static int
> +lbox_on_rollback(struct lua_State *L)
> +{
> +	lbox_on_txn_end(rollback);
> +}
> +

This is nit-picking, but IMHO better define the whole function
in a macro.

#define LBOX_TXN_TRIGGER(name)					\
static int							\
lbox_on_##name(struct lua_State *L)				\
...

LBOX_TXN_TRIGGER(commit)
LBOX_TXN_TRIGGER(rollback)

Other than that the patch looks good to me.