From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Francesco =?UTF-8?Q?Potort=C3=AC?= Newsgroups: gmane.emacs.bugs Subject: bug#25458: 25.1; tar mode does not handle compressed archives without specific extensions Date: Fri, 13 May 2022 16:45:42 +0200 Organization: The GNU project Message-ID: <87tu9tmqy1.fsf@tucano.isti.cnr.it> References: <87o801serb.fsf@gnus.org> <83ilq9ms6n.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="5075"; mail-complaints-to="usenet@ciao.gmane.io" Cc: 25458@debbugs.gnu.org, Lars Ingebrigtsen To: Eli Zaretskii Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Fri May 13 16:46:15 2022 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1npWYY-00017Q-3k for geb-bug-gnu-emacs@m.gmane-mx.org; Fri, 13 May 2022 16:46:14 +0200 Original-Received: from localhost ([::1]:51940 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1npWYW-0005up-To for geb-bug-gnu-emacs@m.gmane-mx.org; Fri, 13 May 2022 10:46:12 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:59842) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1npWYM-0005rn-U3 for bug-gnu-emacs@gnu.org; Fri, 13 May 2022 10:46:02 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:50611) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1npWYM-0006eH-Gh for bug-gnu-emacs@gnu.org; Fri, 13 May 2022 10:46:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1npWYM-0007bA-EJ for bug-gnu-emacs@gnu.org; Fri, 13 May 2022 10:46:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Francesco =?UTF-8?Q?Potort=C3=AC?= Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Fri, 13 May 2022 14:46:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 25458 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: moreinfo Original-Received: via spool by 25458-submit@debbugs.gnu.org id=B25458.165245314929179 (code B ref 25458); Fri, 13 May 2022 14:46:02 +0000 Original-Received: (at 25458) by debbugs.gnu.org; 13 May 2022 14:45:49 +0000 Original-Received: from localhost ([127.0.0.1]:44508 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1npWY8-0007aZ-KY for submit@debbugs.gnu.org; Fri, 13 May 2022 10:45:48 -0400 Original-Received: from plesklin7.if1.ehiweb.it ([79.98.45.16]:47796) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1npWY6-0007aJ-Qh for 25458@debbugs.gnu.org; Fri, 13 May 2022 10:45:47 -0400 Original-Received: from tucano.isti.cnr.it (tucano.isti.cnr.it [146.48.81.102]) by plesklin7.if1.ehiweb.it (Postfix) with ESMTPSA id A4D22108375; Fri, 13 May 2022 16:45:42 +0200 (CEST) In-Reply-To: <83ilq9ms6n.fsf@gnu.org> (eliz@gnu.org) X-fingerprint: 4B02 6187 5C03 D6B1 2E31 7666 09DF 2DC9 BE21 6115 X-PPP-Message-ID: <20220513144542.32562.54614@plesklin7.if1.ehiweb.it> X-PPP-Vhost: potorti.it X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.io gmane.emacs.bugs:232158 Archived-At: >> Cc: 25458@debbugs.gnu.org >> From: Lars Ingebrigtsen >> Date: Fri, 13 May 2022 16:12:24 +0200 >> >> Francesco Potortì writes: >> >> > By looking at the comments on top of tar-mode.el, I get that it does not >> > rely on tar to get the archive listing, but reads the archive itself, so >> > correcting this problem does not appear straightforward to me... >> >> (I'm going through old bug reports that unfortunately weren't resolved >> at the time.) >> >> If Emacs had code to automatically recognise compressed data, I guess >> tar-mode could decompress the buffer before it started working on it. >> (Does Emacs have that? I guess we could add stuff to >> `magic-fallback-mode-alist' or something in that region...) > >But decompressing means, for most compression types, running an >external program on the file. Or does OP suggest that we link Emacs >against libbz2, liblz4, liblzma, etc. to have these decompression >methods available in core? If Emacs parses the tar file itself, without relying on tar, in principle it should read compressed tar files too. It could do that by using external compression tools, or more efficiently by natively handling compression. However, I think that in general this requires uncompressing the whole tar file in memory or on disk, which is against one of the main purposes stated in the inital comments of tar-mode.el.