[dpdk-dev] [RFC 1/4] ring: future proof flag settings

[Ananyev, Konstantin]

> -----Original Message-----
> From: dev <dev-bounces at dpdk.org> On Behalf Of Stephen Hemminger
> Sent: Wednesday, February 12, 2020 11:08 PM
> To: dev at dpdk.org
> Cc: Stephen Hemminger <stephen at networkplumber.org>
> Subject: [dpdk-dev] [RFC 1/4] ring: future proof flag settings
> 
> All API's should check that they support the flag values
> passed. If an application passes an invalid flag it could
> cause problems in later ABI.
> 
> Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
> ---
>  lib/librte_ring/rte_ring.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/lib/librte_ring/rte_ring.c b/lib/librte_ring/rte_ring.c
> index 77e5de099b81..6cd8831649ea 100644
> --- a/lib/librte_ring/rte_ring.c
> +++ b/lib/librte_ring/rte_ring.c
> @@ -100,6 +100,13 @@ rte_ring_init(struct rte_ring *r, const char *name, unsigned count,
>  	RTE_BUILD_BUG_ON((offsetof(struct rte_ring, prod) &
>  			  RTE_CACHE_LINE_MASK) != 0);
> 
> +	/* future proof flags, only allow supported values */
> +	if (flags & ~(RING_F_SP_ENQ | RING_F_SC_DEQ)) {
> +		RTE_LOG(ERR, RING,
> +			"Unsupported flags requested %d\n", flags);
> +		return -EINVAL;
> +	}
> +

Good idea, I think, but seems you forgot RING_F_EXACT_SZ.

>  	/* init the ring structure */
>  	memset(r, 0, sizeof(*r));
>  	ret = strlcpy(r->name, name, sizeof(r->name));
> --
> 2.20.1