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To: "dev@dpdk.org" <dev@dpdk.org>, Ferruh Yigit <ferruh.yigit@intel.com>,
 Andrew Rybchenko <Andrew.Rybchenko@oktetlabs.ru>, Thomas Monjalon
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From: "Min Hu (Connor)" <humin29@huawei.com>
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Date: Wed, 7 Apr 2021 19:28:18 +0800
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Subject: [dpdk-dev] Questions about API with no parameter check
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Hi, all,
	Many APIs in DPDK does not check if the pointer parameter is
NULL or not. For example, in 'rte_ethdev.c':
int
rte_eth_rx_queue_setup(uint16_t port_id, uint16_t rx_queue_id,
		       uint16_t nb_rx_desc, unsigned int socket_id,
		       const struct rte_eth_rxconf *rx_conf,
		       struct rte_mempool *mp)

int
rte_eth_link_get(uint16_t port_id, struct rte_eth_link *eth_link)

int
rte_eth_stats_get(uint16_t port_id, struct rte_eth_stats *stats)

int
rte_eth_dev_info_get(uint16_t port_id, struct rte_eth_dev_info *dev_info)

As these APIs could be used by any APPs, if the APP give NULL as
the pointer parameter, segmetation default will occur.

So, my question is, should we add check in the API? like that,
int rte_eth_stats_get(uint16_t port_id, struct rte_eth_stats *stats)
{
	if (stats == NULL)
		return -EINVAL;
	...
}

Or, that is redundant, the parameter correctness should be guaranteed by
the APP?

What's your opinion? Hope for your reply.
	Thanks.