On Mon, Apr 16, 2012 at 11:27:55PM +0100, Ed W wrote: >On 16/04/2012 23:02, Ed W wrote: >>On 16/04/2012 18:32, Rich Felker wrote: >>>On Mon, Apr 16, 2012 at 05:57:47PM +0100, Ed W wrote: >>>>Rich, disregarding posix for a moment, what does glibc do? Options >>>>are: canonname=NULL or IP as string? >>>If the AI_CANONNAME flag is not specified, the value of the >>>ai_canonname field in the returned structure is unspecified; in this >>>case it should not be filled in at all unless there's no cost to >>>filling it (IIRC musl always fills it because filling it is free if >>>done right). >>> >>>>At present uclibc is returning the reverse dns lookup or textual IP >>>>format. It should be trivial for me to supply a patch to make this >>>>whatever we want - can someone define what we want? (Posix or >>>>emulate some other wierdness?) >>>Per POSIX: >>> >>> If nodename is not null, and if requested by the AI_CANONNAME >>> flag, the ai_canonname field of the first returned addrinfo >>> structure shall point to a null-terminated string containing the >>> canonical name corresponding to the input nodename; if the >>> canonical name is not available, then ai_canonname shall refer to >>> the nodename argument or a string with the same contents. The >>> contents of the ai_flags field of the returned structures are >>> undefined. >>> >>>My reading is that in the numeric case, since there is no canonical >>>name, the text about storing a pointer to the input nodename, or a >>>duplicate of the same, applies. >>> >> >>OK, please see attached version 2 of my patch which I believe >>implements this satisfactorarily >> >>As before the motivation is to avoid making DNS queries when >>calling getaddrinfo with a numerical IP address. Performance >>improves dramatically in such situations >> >>Grateful if others with more experience will verify and commit > >Sorry, typo - s/NUMERICSERV/NUMERICHOST/ > >Patch re-attached v3 > >Ed W
>Posix says that canonname should use the text representation of an IP address >when a numerical nodename given >See: http://pubs.opengroup.org/onlinepubs/9699919799/functions/getaddrinfo.html > >Signed-off-by: Ed Wildgoose <[email protected]> Applied, thanks! _______________________________________________ uClibc mailing list [email protected] http://lists.busybox.net/mailman/listinfo/uclibc
