From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Shawn O. Pearce" Subject: Re: mark parsing in fast-import Date: Tue, 22 Apr 2008 19:15:15 -0400 Message-ID: <20080422231515.GJ29771@spearce.org> References: <1208132469-26471-3-git-send-email-joerg@alea.gnuu.de> <1208169584-15931-1-git-send-email-joerg@alea.gnuu.de> <20080414232958.GE20979@spearce.org> <20080420234438.GC12865@alea.gnuu.de> <20080421002626.GJ29771@spearce.org> <20080421084151.GA31344@alea.gnuu.de> <20080421235940.GQ29771@spearce.org> <20080422093942.GA3752@alea.gnuu.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: git@vger.kernel.org To: =?utf-8?B?SsO2cmc=?= Sommer X-From: git-owner@vger.kernel.org Wed Apr 23 01:16:14 2008 connect(): Connection refused Return-path: Envelope-to: gcvg-git-2@gmane.org Received: from vger.kernel.org ([209.132.176.167]) by lo.gmane.org with esmtp (Exim 4.50) id 1JoRib-00011V-0Y for gcvg-git-2@gmane.org; Wed, 23 Apr 2008 01:16:09 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763197AbYDVXPU (ORCPT ); Tue, 22 Apr 2008 19:15:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751599AbYDVXPU (ORCPT ); Tue, 22 Apr 2008 19:15:20 -0400 Received: from corvette.plexpod.net ([64.38.20.226]:33702 "EHLO corvette.plexpod.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762767AbYDVXPS (ORCPT ); Tue, 22 Apr 2008 19:15:18 -0400 Received: from cpe-74-70-48-173.nycap.res.rr.com ([74.70.48.173] helo=asimov.home.spearce.org) by corvette.plexpod.net with esmtpa (Exim 4.68) (envelope-from ) id 1JoRha-0006DB-Ak; Tue, 22 Apr 2008 19:15:06 -0400 Received: by asimov.home.spearce.org (Postfix, from userid 1000) id 2604320FBAE; Tue, 22 Apr 2008 19:15:15 -0400 (EDT) Content-Disposition: inline In-Reply-To: <20080422093942.GA3752@alea.gnuu.de> User-Agent: Mutt/1.5.11 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - corvette.plexpod.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - spearce.org Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Jrg Sommer wrote: > > Another question: Is :0 a valid mark? In import_marks() is a check for > !mark, but I haven't seen it anywhere else. No, in fast-import ":0" is _not_ a valid mark. We burn the first entry in the marks table (always leaving it empty) as then we can use the idiom "!mark" to say "no mark was requested/given" and "mark" to say "mark was requested/given". Hence we do not need an extra flag to tell us either way. Given that a mark is just a pointer, and that extra flag would likely have been a global "static int have_mark" or some such it works out to be about the same amount of memory - 4 or 8 bytes. No big deal, and the code is probably easier to follow as a result. -- Shawn.