X-Recipient:	archive-cygwin AT delorie DOT com
DKIM-Filter:	OpenDKIM Filter v2.11.0 sourceware.org 5DBED385AC28
DKIM-Signature:	v=1; a=rsa-sha256; c=relaxed/relaxed; d=cygwin.com;
	s=default; t=1637071622;
	bh=/TD3H4M7K+uLVM0t/ei7FTb2jHUxMhTfE5TKQzNVb94=;
	h=Date:To:Subject:References:In-Reply-To:List-Id:List-Unsubscribe:
	List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc:
	From;
	b=OIxGHix8DdEw99wTKSF9A7fCWjY/R5OjIPgwzzPbaRYkp1FsZLaAFa2QuMSllVn4J
	6VQ6hFuCHuJeTumDtnjItAdCj5pIanfCtXD69ZZ8JmzC7AIsQ6v5/l85xHkgLH8eGi
	Sy5LXeqtzcYTAEGEZZyhYVGvshCXBG7T2XZSMBVA=
X-Original-To:	cygwin AT cygwin DOT com
Delivered-To:	cygwin AT cygwin DOT com
DMARC-Filter:	OpenDMARC Filter v1.4.1 sourceware.org BA50F385B804
Date:	Tue, 16 Nov 2021 15:06:27 +0100
To:	cygwin AT cygwin DOT com
Subject:	Re: Editing with vim clears Windows 10 file system archive bit.
Message-ID:	<YZO6435IBP+UmU0F@calimero.vinschen.de>
Mail-Followup-To:	cygwin AT cygwin DOT com
References:	<SN6PR04MB4799AEB60421601D02E22680BB979 AT SN6PR04MB4799 DOT namprd04 DOT prod DOT outlook DOT com>
	<305aedc4-9bb2-02b8-f5ab-f88aba39e9cf AT t-online DOT de>
	<YZK9ciahf8PDvX7A AT calimero DOT vinschen DOT de>
	<20211115221818 DOT GA12715 AT phoenix>
MIME-Version:	1.0
In-Reply-To:	<20211115221818.GA12715@phoenix>
X-Provags-ID:	V03:K1:pt0dUkcYIxjQVpVJZFEpq3aFMqTyOB7hh1HYQyc6An7XyNh68fq
	qVmqCI8amIantbQV/HvHJjpH5M6SJUmavbaCTr95viQQkg4f1pVemrf543mqqBR2eg3VYC6
	amQ6zm8gqC6ujSVkLdT7hFDoE9XiJf/vCgysXvv1zh63+rw9m5KSBlOg6IbwbGZav81mpew
	I3gFVUy16vJnNjmv3vVEQ==
X-UI-Out-Filterresults:	notjunk:1;V03:K0:GY2dwOiGkEk=:u33X4fIzpRND9H6eMQFH+Z
	xE7yKTEj54PCtRzcnVwDk5aMoQFzi9q232238wZuf2S+uaSYZLP2wb8XKiOdXA7jG8TyUiRRI
	OT+K/5zfVpU1DXksRFHk0dNeh2UuriVJ8A3FAISyRrAgyQlalaTSjc1RAOjMBVjyXj2E2g1VW
	xe5lRd5oN4NkaKPA4kuumnqrmpVDUDPGKzLOe5lB7BJkpdNnBB5Z59gw8azeRdZI7AX4o0o3d
	JfPIeITJ/+p0ANXqVaRjDblFHOrOB/RrL4yF4g764VWRaL8/JmmKFRxPbPp8iHnGdrHmpICe4
	dxbX674ErdVubcEq97An0ojuMwblfxHKDVeykG5Bx/4mA0H0HiVkWrQ1ig2u7LwNLTS/4UjlW
	OTw2mln7Minz8mAUMD0aEqFDLQ1kRQjmH2q6DDVfNkX9S1hUuPz5v11Ls7sqbVWfiHpd9hZUx
	Sjrok5n7gY2L9b80nW/LIrhbtkeaOuudtMOVbrlJHJ4IHTJnBAuV+IdQxNtc2oV7tsZSFqJ1k
	gf2hFWW0UFGRUhqgS14/WOJm0dbsjWCcKxLZ6AuQurEM2twjoFZ2p7AK6NJVnEz5n/95RQGxZ
	Kh7Bb12thvymC2RHt64aELiCWB7ZENXCgF5nAFqBi5Svv0nj/IOLJLpBLhJyiFC6q0aTXtnoF
	msGjFm4BD+guL9w78fD6cyMzZMXyGtaDdMI6WhqOV9ixwb+83DK6Jg051i62hGO7ZhzVo+o2X
	6HzYwXhS83cPSnih
X-Spam-Status:	No, score=-99.1 required=5.0 tests=BAYES_00,
	GOOD_FROM_CORINNA_CYGWIN, JMQ_SPF_NEUTRAL, KAM_DMARC_NONE, KAM_DMARC_STATUS,
	RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NEUTRAL,
	TXREP autolearn=ham autolearn_force=no version=3.4.4
X-Spam-Checker-Version:	SpamAssassin 3.4.4 (2020-01-24) on
	server2.sourceware.org
X-BeenThere:	cygwin AT cygwin DOT com
X-Mailman-Version:	2.1.29
List-Id:	General Cygwin discussions and problem reports <cygwin.cygwin.com>
List-Unsubscribe:	<https://cygwin.com/mailman/options/cygwin>,
	<mailto:cygwin-request AT cygwin DOT com?subject=unsubscribe>
List-Archive:	<https://cygwin.com/pipermail/cygwin/>
List-Post:	<mailto:cygwin AT cygwin DOT com>
List-Help:	<mailto:cygwin-request AT cygwin DOT com?subject=help>
List-Subscribe:	<https://cygwin.com/mailman/listinfo/cygwin>,
	<mailto:cygwin-request AT cygwin DOT com?subject=subscribe>
From:	Corinna Vinschen via Cygwin <cygwin AT cygwin DOT com>
Reply-To:	cygwin AT cygwin DOT com
Cc:	Corinna Vinschen <corinna-cygwin AT cygwin DOT com>
Errors-To:	cygwin-bounces+archive-cygwin=delorie DOT com AT cygwin DOT com
Sender:	"Cygwin" <cygwin-bounces+archive-cygwin=delorie DOT com AT cygwin DOT com>

On Nov 15 14:18, Gary Johnson wrote:
> On 2021-11-15, Corinna Vinschen via Cygwin wrote:
> > Changing that is actually pretty simple, just set FILE_ATTRIBUTE_ARCHIVE
> > as soon as the underlying NtCreateFile is called for an open(O_CREAT).
> > 
> > Fixed in current git.
> 
> I had thought that this might be a bug in Vim, so did a git bisect
> to find the offending commit.  For the record, it was this one:
> [...]
> The only change I see to an open() call was removing O_TRUNC on
> systems with ftruncate() and adding a later call to ftruncate() on
> systems that have it.  There were also some changes to the setting
> of permissions (fchown(), fchmod() and chmod()).  These changes were
> all in the buf_write() function in fileio.c.
> 
> That open() call had the O_CREAT flag before and after the change.

You are sooo right.

My bugfix appears to work, but it's fixing a non-existent bug.
NtCreateFile actually sets the ARCHIVE bit all the time when creating a
new file, even if it's not explicitely given as parameter.  That makes a
lot of sense, of course, given how the archiving mechanism works on
Windows.

The *real* problem is in fact that Cygwin caches the wrong file
attribute bits when creating a new file, and that's where fchmod fails:
It writes back the wrongly cached bits.  This doesn't happen with
chmod, because it re-opens the existing file and fetches the correct
attributes bit at the time.

I guess I'll revert my patch and create a new one which is more to the
point.


Thanks,
Corinna

-- 
Problem reports:      https://cygwin.com/problems.html
FAQ:                  https://cygwin.com/faq/
Documentation:        https://cygwin.com/docs.html
Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple

- Raw text -