From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 3D6661FF40 for ; Thu, 23 Jun 2016 19:22:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752024AbcFWTWz (ORCPT ); Thu, 23 Jun 2016 15:22:55 -0400 Received: from cloud.peff.net ([50.56.180.127]:59296 "HELO cloud.peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751605AbcFWTWy (ORCPT ); Thu, 23 Jun 2016 15:22:54 -0400 Received: (qmail 2164 invoked by uid 102); 23 Jun 2016 19:22:54 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.84) with SMTP; Thu, 23 Jun 2016 15:22:54 -0400 Received: (qmail 14087 invoked by uid 107); 23 Jun 2016 19:23:08 -0000 Received: from sigill.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.7) by peff.net (qpsmtpd/0.84) with SMTP; Thu, 23 Jun 2016 15:23:08 -0400 Received: by sigill.intra.peff.net (sSMTP sendmail emulation); Thu, 23 Jun 2016 15:22:51 -0400 Date: Thu, 23 Jun 2016 15:22:51 -0400 From: Jeff King To: =?utf-8?B?UmVuw6k=?= Scharfe Cc: git@vger.kernel.org Subject: Re: [PATCH 2/2] archive-tar: write extended headers for far-future mtime Message-ID: <20160623192251.GB32745@sigill.intra.peff.net> References: <20160616043523.GA13615@sigill.intra.peff.net> <20160616043758.GB18323@sigill.intra.peff.net> <57687417.4020009@web.de> <576A2631.2000608@web.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <576A2631.2000608@web.de> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Wed, Jun 22, 2016 at 07:46:25AM +0200, René Scharfe wrote: > Am 21.06.2016 um 00:54 schrieb René Scharfe: > > Am 16.06.2016 um 06:37 schrieb Jeff King: > > > 2. System tars that cannot handle pax headers. > > > > In t5000 there is a simple interpreter for path headers for systems > > whose tar doesn't handle them. Adding one for mtime headers may be > > feasible. > > > > It's just a bit complicated to link a pax header file to the file it > > applies to when it doesn't also contain a path header. But we know that > > the mtime of all entries in tar files created by git archive are is the > > same, so we could simply read one header and then adjust the mtime of > > all files accordingly. > > This brings me to the idea of using a single global pax header for mtime > instead of one per entry. It reduces the size of the archive and allows for > slightly easier testing -- it just fits better since we know that all our > mtimes are the same. Yeah, I had a similar thought while writing it, but wasn't quite sure how that was supposed to be formatted. I modeled my output after what GNU tar writes, but of course they are expecting a different mtime for each file. I'll look into how global pax headers should look. -Peff