From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9921BC2BA19 for ; Tue, 14 Apr 2020 10:04:59 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5E23A2072D for ; Tue, 14 Apr 2020 10:04:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="AlPi3Kxk" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5E23A2072D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:55262 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jOIR8-0004lo-Js for qemu-devel@archiver.kernel.org; Tue, 14 Apr 2020 06:04:58 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:34714) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jOIQN-0003vu-Ql for qemu-devel@nongnu.org; Tue, 14 Apr 2020 06:04:12 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1jOIQM-0001aC-8G for qemu-devel@nongnu.org; Tue, 14 Apr 2020 06:04:11 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:43630 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1jOIQM-0001Zi-2G for qemu-devel@nongnu.org; Tue, 14 Apr 2020 06:04:10 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1586858649; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=K3/9PAsRVLGzUvdFOhxXxSRuwc/IHBzXF6b6U4JVseM=; b=AlPi3KxkdeiEmAQPP17m7KUz2yXHsEpXuklp6eN9kpheNk2eg68/pRozBCgCJyPKsLqzMh TtjeI6Oac7YY+9sdhYcRd74OCy17S+Dfx7v35fvhmgusc81fIcCC2Jca4tj06oexlx8ASB YaWjposQkztaPV3UokTkhuP31PVW1bc= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-442-ULNyNPOMM9eTciiXVMKHSw-1; Tue, 14 Apr 2020 06:04:06 -0400 X-MC-Unique: ULNyNPOMM9eTciiXVMKHSw-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id EF35D18B9FC1; Tue, 14 Apr 2020 10:04:05 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-113-20.ams2.redhat.com [10.36.113.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id BA51B5C1B0; Tue, 14 Apr 2020 10:04:05 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 3C7A611385C8; Tue, 14 Apr 2020 12:04:04 +0200 (CEST) From: Markus Armbruster To: Eric Blake Subject: Re: [PATCH for-5.1 4/8] qemu-option: Avoid has_help_option() in qemu_opts_parse_noisily() References: <20200409153041.17576-1-armbru@redhat.com> <20200409153041.17576-5-armbru@redhat.com> <4f38f94d-5c7a-c00f-c7dc-8bc28de4fd39@redhat.com> Date: Tue, 14 Apr 2020 12:04:04 +0200 In-Reply-To: <4f38f94d-5c7a-c00f-c7dc-8bc28de4fd39@redhat.com> (Eric Blake's message of "Thu, 9 Apr 2020 13:07:31 -0500") Message-ID: <871roqwfhn.fsf@dusky.pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 205.139.110.61 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, qemu-devel@nongnu.org, qemu-block@nongnu.org, mreitz@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Eric Blake writes: > On 4/9/20 10:30 AM, Markus Armbruster wrote: >> When opts_parse() sets @invalidp to true, qemu_opts_parse_noisily() >> uses has_help_option() to decide whether to print help. This parses >> the input string a second time, in a slightly different way. >> >> Easy to avoid: replace @invalidp by @help_wanted. >> >> Signed-off-by: Markus Armbruster >> --- >> util/qemu-option.c | 20 ++++++++++---------- >> 1 file changed, 10 insertions(+), 10 deletions(-) >> > >> - opts =3D opts_parse(list, params, permit_abbrev, false, &invalidp, = &err); >> + opts =3D opts_parse(list, params, permit_abbrev, false, &help_wante= d, &err); >> if (err) { >> - if (invalidp && has_help_option(params)) { >> + if (help_wanted) { > > Yep, that is cleaner. Should there be testsuite coverage changing as > a result of this? Hmm. I guess the actual question is whether this patch changes behavior. @invalidp gets set to true when opt_set() runs into an unknown @name. Aside: can't happend when opts_accepts_any(); such options can't rely on qemu_opts_parse_noisily() providing help. One reason for unknown @name is the user asking for help. We want to provide it then. To find out, we use has_help_option(), which parses certain corner cases differently. PATCH 1 demonstrates it can return false incorrectly for certain corner cases. This patch fixes qemu_opts_parse_noisily() to provide help as it should even for these corner cases. What about this: * I put PATCH 5 "qemu-option: Fix has_help_option()'s sloppy parsing" before this one, so that this one doesn't change behavior. * I adjust this one's commit message accordingly: scratch ", in a slightly different way". Do we care enough to further document the bug fix in PATCH 5's commit message? Even find an actual CLI option that reproduces the bug? I doubt it. This is all about silly corner cases involving ','. Perhaps has_help_option() can also return true incorrectly. I doubt we care. > Reviewed-by: Eric Blake Thanks!