From owner-freebsd-net@FreeBSD.ORG Tue Jan 22 21:57:35 2013 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by hub.freebsd.org (Postfix) with ESMTP id EBA06C73; Tue, 22 Jan 2013 21:57:35 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from bigwig.baldwin.cx (bigknife-pt.tunnel.tserv9.chi1.ipv6.he.net [IPv6:2001:470:1f10:75::2]) by mx1.freebsd.org (Postfix) with ESMTP id AE0638D4; Tue, 22 Jan 2013 21:57:35 +0000 (UTC) Received: from pakbsde14.localnet (unknown [38.105.238.108]) by bigwig.baldwin.cx (Postfix) with ESMTPSA id 52337B953; Tue, 22 Jan 2013 16:57:34 -0500 (EST) From: John Baldwin To: freebsd-net@freebsd.org Subject: Re: [PATCH] Don't imply TCP and UDP socket options are bitmasks Date: Tue, 22 Jan 2013 15:28:18 -0500 User-Agent: KMail/1.13.5 (FreeBSD/8.2-CBSD-20110714-p22; KDE/4.5.5; amd64; ; ) References: <201301141550.13577.jhb@freebsd.org> <201301151416.07231.jhb@freebsd.org> <50FE5473.7000807@freebsd.org> In-Reply-To: <50FE5473.7000807@freebsd.org> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201301221528.18388.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.7 (bigwig.baldwin.cx); Tue, 22 Jan 2013 16:57:34 -0500 (EST) Cc: Lawrence Stewart X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 22 Jan 2013 21:57:36 -0000 On Tuesday, January 22, 2013 3:57:23 am Lawrence Stewart wrote: > On 01/16/13 06:16, John Baldwin wrote: > > On Tuesday, January 15, 2013 3:49:33 am Lawrence Stewart wrote: > >> On 01/15/13 07:50, John Baldwin wrote: > >>> The constants used for TCP and UDP socket options (TCP_NODELAY, etc.) are > >>> currently defined as hex values that are individual bits. However, socket > >>> options are never masked together, they are used as a simple enumeration of > >>> discrete values. Using a bitmask forces us to run out of bits and makes it > >>> harder for vendors to try to use a high range of values for local custom > >>> options (hoping that they never conflict with a new option value added in > >>> stock FreeBSD). > >> > >> Yup. Should we be explicitly #defining the boundary between "bits > >> reserved for FreeBSD" and "bits for private vendor use"? > > > > Oh, we could if you wanted. I'm using 0x1000 locally for both TCP and UDP, > > but those are completely arbitrary values. Saner ones might be 0x8000000 if > > we want to do that explicitly. We could perhaps just say that is true for all > > socket option levels (that is, just define one SO_VENDOR constant or some such > > but say it applies to all levels)? > > A single SO_VENDOR applied to all levels sounds good to me. Ok, how about this for wording: Index: sys/socket.h =================================================================== --- socket.h (revision 245742) +++ socket.h (working copy) @@ -143,6 +143,15 @@ typedef __uid_t uid_t; #endif /* + * Space reserved for new socket options added by third-party vendors. + * This range applies to all socket option levels. New socket options + * in FreeBSD should always use an option value less than SO_VENDOR. + */ +#if __BSD_VISIBLE +#define SO_VENDOR 0x80000000 +#endif + +/* * Structure used for manipulating linger option. */ struct linger { -- John Baldwin