From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-4.1 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD shortcircuit=no autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id B377E207BC for ; Wed, 19 Apr 2017 02:57:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758495AbdDSC5f (ORCPT ); Tue, 18 Apr 2017 22:57:35 -0400 Received: from pb-smtp1.pobox.com ([64.147.108.70]:60504 "EHLO sasl.smtp.pobox.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752077AbdDSC5e (ORCPT ); Tue, 18 Apr 2017 22:57:34 -0400 Received: from sasl.smtp.pobox.com (unknown [127.0.0.1]) by pb-smtp1.pobox.com (Postfix) with ESMTP id 40D7182326; Tue, 18 Apr 2017 22:57:33 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type; s=sasl; bh=q9ofnkh+pSpAbRkNwsL8dAWb3U4=; b=jG7uGw KB8RZV+TUUfM7Z8jg5BVDL7LJwxY+cHKTaXl2lvQt6K8Snyh5+JFidxU2z6c5s8F jQlXNc/qtzkC0hP7g0x+jN8k5W9hLAGyzmlF4fQ5w7K1z4asdeNxcmfEWBFdjfgC XA13M2E4SiqMojiZmnI8TzqOAUm7aVNjaaxVw= DomainKey-Signature: a=rsa-sha1; c=nofws; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type; q=dns; s=sasl; b=HKmPqdHGBOzdI4wqBDfb1jfN3ptr+ScG ik4bFQJI5gvnGJt238xEnDJ/yrzxKigkwBJ5xmDdW99E4BsAigh+/9/j9GB5bsj2 Z9vQdCIyefF8kCmdNXB74R5GhfZsS64CUtnYTwEJ0mwuIuUMythNNS0YmnNqWbxx aTEqktBfEtw= Received: from pb-smtp1.nyi.icgroup.com (unknown [127.0.0.1]) by pb-smtp1.pobox.com (Postfix) with ESMTP id 3975782325; Tue, 18 Apr 2017 22:57:33 -0400 (EDT) Received: from pobox.com (unknown [104.132.0.95]) (using TLSv1.2 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by pb-smtp1.pobox.com (Postfix) with ESMTPSA id 9EFDF82324; Tue, 18 Apr 2017 22:57:32 -0400 (EDT) From: Junio C Hamano To: Jonathan Nieder Cc: David Turner , git@vger.kernel.org, l.s.r@web.de Subject: Re: [PATCH v3 1/2] use HOST_NAME_MAX to size buffers for gethostname(2) References: <20170418215743.18406-1-dturner@twosigma.com> <20170418215743.18406-2-dturner@twosigma.com> <20170419012824.GA28740@aiede.svl.corp.google.com> Date: Tue, 18 Apr 2017 19:57:31 -0700 In-Reply-To: <20170419012824.GA28740@aiede.svl.corp.google.com> (Jonathan Nieder's message of "Tue, 18 Apr 2017 18:28:24 -0700") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.1.91 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Pobox-Relay-ID: EF0C0BA4-24AB-11E7-841A-E680B56B9B0B-77302942!pb-smtp1.pobox.com Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Jonathan Nieder writes: >> @@ -274,7 +278,7 @@ static const char *lock_repo_for_gc(int force, pid_t* ret_pid) >> * running. >> */ >> time(NULL) - st.st_mtime <= 12 * 3600 && >> - fscanf(fp, "%"SCNuMAX" %127c", &pid, locking_host) == 2 && >> + fscanf(fp, scan_fmt, &pid, locking_host) == 2 && > > I hoped this could be simplified since HOST_NAME_MAX is a numeric literal, > using the double-expansion trick: > > #define STR_(s) # s > #define STR(s) STR_(s) > > fscanf(fp, "%" SCNuMAX " %" STR(HOST_NAME_MAX) "c", > &pid, locking_host); > > Unfortunately, I don't think there's anything stopping a platform from > defining > > #define HOST_NAME_MAX 0x100 > > which would break that. Yes, that was exactly why I went to the xstrfmt() route when I sent mine yesterday ;-). > So this run-time calculation appears to be necessary. > > Reviewed-by: Jonathan Nieder Thanks.