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=-3.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 67D54C4361B for ; Mon, 7 Dec 2020 16:27:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1FC112376F for ; Mon, 7 Dec 2020 16:27:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726952AbgLGQ06 convert rfc822-to-8bit (ORCPT ); Mon, 7 Dec 2020 11:26:58 -0500 Received: from eu-smtp-delivery-151.mimecast.com ([207.82.80.151]:50997 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726250AbgLGQ05 (ORCPT ); Mon, 7 Dec 2020 11:26:57 -0500 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-214-Bby5aBFqM56ZRCF6phHXMw-1; Mon, 07 Dec 2020 16:25:18 +0000 X-MC-Unique: Bby5aBFqM56ZRCF6phHXMw-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) by AcuMS.aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Mon, 7 Dec 2020 16:25:17 +0000 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Mon, 7 Dec 2020 16:25:17 +0000 From: David Laight To: 'Steven Rostedt' , James Bottomley CC: Ard Biesheuvel , "laniel_francis@privacyrequired.com" , linux-efi , Linux Kernel Mailing List Subject: RE: [RFC PATCH v1 07/12] efi: Replace strstarts() by str_has_prefix(). Thread-Topic: [RFC PATCH v1 07/12] efi: Replace strstarts() by str_has_prefix(). Thread-Index: AQHWzKs0kz/fG1FbOEiEJcYInMSfrqnr0Lsg Date: Mon, 7 Dec 2020 16:25:17 +0000 Message-ID: <70d98067245c4b4ebb411e68fb3162ef@AcuMS.aculab.com> References: <20201204170319.20383-1-laniel_francis@privacyrequired.com> <20201204170319.20383-8-laniel_francis@privacyrequired.com> <3161fc13d69c388b1f51f59c6ecea48dcd0a7856.camel@HansenPartnership.com> <043040d9c092cedcab8bf88b0ec805616d3be44d.camel@HansenPartnership.com> <8a169362defed5af16be78c5a11f4ff9f58da2a8.camel@HansenPartnership.com> <20201207101025.1d133a5d@gandalf.local.home> In-Reply-To: <20201207101025.1d133a5d@gandalf.local.home> Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=C51A453 smtp.mailfrom=david.laight@aculab.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Steven Rostedt > Sent: 07 December 2020 15:10 > > On Sat, 05 Dec 2020 15:04:31 -0800 > James Bottomley wrote: > > > Well, I think the pattern > > > > if (strstarts(option, )) { > > ... > > option += strlen(); > > > > is a bad one because one day may get updated but not > string>. And if is too far away in the code it might not > > even show up in the diff, leading to reviewers not noticing either. So > > I think eliminating the pattern is a definite improvement. > > And one of the reasons we created str_has_prefix() is because we fixed that > exact bug, in a few places. > > It was caused by a typo, where we had something like: > > strstarts(option, "foo=") { > option += strlen("foo"); > > and forgot the "=" part, and broke the rest of the logic. And then someone else wonders whether the paint is the right colour. Maybe the function should return the pointer to the character after the prefix. Suddenly you have a load of functions to pick from, none do quite what you want - so you add yet another :-) David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)