>>>>> On Wed, 28 Apr 2004 17:09:30 -0700,
>>>>> "George V. Neville-Neil" <[EMAIL PROTECTED]> said:
> This should be a minor nit but, is there any reason we
> implement this this way:
> #define CMSG_FIRSTHDR(mhdr) ((struct cmsghdr *)(mhdr)->msg_control)
> instead of this way:
> #define CMSG_FIRSTHDR(mhdr) \
> ( (mhdr)->msg_controllen >= sizeof(struct cmsghdr) ? \
> (struct cmsghdr *)(mhdr)->msg_control : \
> (struct cmsghdr *)NULL )
> as suggested in RFC 2292?
> A coworker of mine asked about this and then I got to wondering
> myself.
I see no special reason. In fact, KAME snapshots have this check as
suggested in RFC2292 (or 3542):
/*
* RFC 2292 requires to check msg_controllen, in case that the kernel returns
* an empty list for some reasons.
*/
#define CMSG_FIRSTHDR(mhdr) \
((mhdr)->msg_controllen >= sizeof(struct cmsghdr) ? \
(struct cmsghdr *)(mhdr)->msg_control : \
(struct cmsghdr *)NULL)
JINMEI, Tatuya
Communication Platform Lab.
Corporate R&D Center, Toshiba Corp.
[EMAIL PROTECTED]
_______________________________________________
[EMAIL PROTECTED] mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-net
To unsubscribe, send any mail to "[EMAIL PROTECTED]"
