[PATCH v2 3/7] tests: check decoding of netlink protocol

[Dmitry V. Levin]

On Mon, Jun 13, 2016 at 02:37:23PM +0000, Fabien Siron wrote:
[...]
> +static void
> +send_query(const int fd)
> +{
> +	struct {
> +		struct nlmsghdr nlh;
> +		char magic[4];
> +	} req = {
> +		.nlh = {
> +			.nlmsg_len = sizeof(req),
> +			.nlmsg_type = SOCK_DIAG_BY_FAMILY,
> +			.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST
> +		},
> +		.magic = "abcd"
> +	};
> +
> +	if (sendto(fd, &req, sizeof(req), MSG_DONTWAIT, NULL, 0) <= 0)
> +		perror_msg_and_skip("sendto");

Why <= 0?  The next statement assumes == (unsigned) sizeof(req).

> +
> +	printf("sendto(%d, {{len=%u, type=20, flags=NLM_F_REQUEST|0x300, "
> +	       "seq=0, pid=0}, \"abcd\"}, 20, MSG_DONTWAIT, NULL, 0) = %u\n",
> +	       fd, (unsigned) sizeof(req), (unsigned) sizeof(req));

Please do not encode values of constants into output strings verbatim.


-- 
ldv
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