From owner-freebsd-arch@FreeBSD.ORG Mon Feb 27 10:20:40 2006 Return-Path: X-Original-To: arch@FreeBSD.org Delivered-To: freebsd-arch@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6351116A422; Mon, 27 Feb 2006 10:20:40 +0000 (GMT) (envelope-from yar@comp.chem.msu.su) Received: from comp.chem.msu.su (comp.chem.msu.su [158.250.32.97]) by mx1.FreeBSD.org (Postfix) with ESMTP id 13BE743D49; Mon, 27 Feb 2006 10:20:35 +0000 (GMT) (envelope-from yar@comp.chem.msu.su) Received: from comp.chem.msu.su (localhost [127.0.0.1]) by comp.chem.msu.su (8.13.3/8.13.3) with ESMTP id k1RAKUL3031795; Mon, 27 Feb 2006 13:20:30 +0300 (MSK) (envelope-from yar@comp.chem.msu.su) Received: (from yar@localhost) by comp.chem.msu.su (8.13.3/8.13.3/Submit) id k1RAKUMk031794; Mon, 27 Feb 2006 13:20:30 +0300 (MSK) (envelope-from yar) Date: Mon, 27 Feb 2006 13:20:30 +0300 From: Yar Tikhiy To: Gleb Smirnoff Message-ID: <20060227102029.GK6435@comp.chem.msu.su> References: <20060227083815.GW55275@cell.sick.ru> <20060227091417.GF6435@comp.chem.msu.su> <20060227083815.GW55275@cell.sick.ru> <4402C09C.C3FB0064@freebsd.org> <20060227093431.GX55275@cell.sick.ru> <20060227094458.GH6435@comp.chem.msu.su> <20060227100031.GY55275@cell.sick.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060227100031.GY55275@cell.sick.ru> User-Agent: Mutt/1.5.9i Cc: arch@FreeBSD.org, Andre Oppermann , jlemon@FreeBSD.org Subject: Re: changing EINVAL for SIOCSIFCAP to something else X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 27 Feb 2006 10:20:40 -0000 On Mon, Feb 27, 2006 at 01:00:31PM +0300, Gleb Smirnoff wrote: > On Mon, Feb 27, 2006 at 12:44:58PM +0300, Yar Tikhiy wrote: > Y> > On Mon, Feb 27, 2006 at 10:04:28AM +0100, Andre Oppermann wrote: > Y> > A> > I prefer this variant: > Y> > A> > > Y> > A> > if (ifp->if_ioctl == NULL) > Y> > A> > return (ENOTTY); > Y> > A> > if (ifr->ifr_reqcap & ~ifp->if_capabilities) > Y> > A> > return (ENODEV); > Y> > A> > > Y> > A> > Any objections? > Y> [...] > Y> > Y> I'm afraid that this is a case when EINVAL is used properly: an > Y> > Y> argument to ioctl doesn't make sense to a particular device. It's > Y> > Y> true that EINVAL may be abused in other places though. I wish each > Y> > Y> EINVAL being returned to the userland were accompanied by log(). > Y> > > Y> > I don't agree. EINVAL can logically fit to almost any error condition. We > Y> > should fine error codes fitting better. If "ioctl doesn't make sense to a > Y> > particular device", then we should say "Operation not supported by device", > Y> > which is ENODEV. > Y> > Y> You see, it isn't ioctl itself that doesn't make sense to the device, > Y> it's a single argument, ifr_reqcap. That was my point. Of course, > > Yes. The ioctl is correct, that's why we do not return ENOTTY. The > argument is correct, that's why we do not return EINVAL. The argument > is not applicable to this device, that's why I suggest to use ENODEV. This interpretation sounds fair to me. Did you look at other cases when ENODEV was returned? How consistent were they with this one? > Y> I won't insist on it because the traditional errno is getting very > Y> limited under the present conditions anyway. -- Yar