X-Recipient:	archive-cygwin AT delorie DOT com
DomainKey-Signature:	a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id
	:list-unsubscribe:list-subscribe:list-archive:list-post
	:list-help:sender:from:to:subject:date:message-id:references
	:in-reply-to:content-type:content-id:content-transfer-encoding
	:mime-version; q=dns; s=default; b=w3E2jzSirIaN0Socgiy2vcgN2GDTl
	1bUFEQ8lshq9kGJqb2M7wrusjJQ/9EhnrObwwiEG5XoFBx/fu6rxFbv41EMvzOQv
	2/lAgcKu2RmpT22VGG26X+dKIS9btqak6rWVCqcNmiAL1kN6SG4aKUzWd730Qn9h
	QuIcPjZRPifLtA=
DKIM-Signature:	v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id
	:list-unsubscribe:list-subscribe:list-archive:list-post
	:list-help:sender:from:to:subject:date:message-id:references
	:in-reply-to:content-type:content-id:content-transfer-encoding
	:mime-version; s=default; bh=A5DIkLWKSswsJqjvAgVhbQ7iLwE=; b=sTI
	NW2cKQF4hMVy1VUa13LrststyyzCSIUtgB1aVf5bB5LymZRRDg3fr2736kr3a9HA
	5FwzKgjPPU4jwsbHKuS7WevJQbM8ZWPfc42dG+nYSjIiMKtJXpVCyDnHVuMPDYWU
	BhHxGtuy/qr5tkGFKgTlm8m6DlW69Vvnu8u+Jrl8=
Mailing-List:	contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id:	<cygwin.cygwin.com>
List-Subscribe:	<mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive:	<http://sourceware.org/ml/cygwin/>
List-Post:	<mailto:cygwin AT cygwin DOT com>
List-Help:	<mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender:	cygwin-owner AT cygwin DOT com
Mail-Followup-To:	cygwin AT cygwin DOT com
Delivered-To:	mailing list cygwin AT cygwin DOT com
Authentication-Results:	sourceware.org; auth=none
X-Virus-Found:	No
X-Spam-SWARE-Status:	No, score=1.9 required=5.0 tests=AWL,BAYES_00,CYGWIN_OWNER_BODY,MIME_BASE64_BLANKS,RCVD_IN_DNSWL_NONE,SPF_HELO_PASS,SPF_PASS autolearn=no version=3.3.2 spammy=Corinna, Hx-exchange-antispam-report-cfa-test:6043046, Hx-exchange-antispam-report-cfa-test:6042046, hesitate
X-HELO:	NAM01-BY2-obe.outbound.protection.outlook.com
From:	Bill Zissimopoulos <billziss AT navimatics DOT com>
To:	"cygwin AT cygwin DOT com" <cygwin AT cygwin DOT com>
Subject:	Re: FUSE, symbolic links and special files
Date:	Tue, 20 Sep 2016 20:56:39 +0000
Message-ID:	<D406EC08.B3C6%billziss@navimatics.com>
References:	<D3E490C7.AEB9%billziss AT navimatics DOT com> <20160825124512 DOT GE9783 AT calimero DOT vinschen DOT de> <D3E512D6.AF5F%billziss AT navimatics DOT com> <20160826080551 DOT GA23935 AT calimero DOT vinschen DOT de> <D3E62581.AFDD%billziss AT navimatics DOT com>
In-Reply-To:	<D3E62581.AFDD%billziss@navimatics.com>
authentication-results:	spf=none (sender IP is ) smtp.mailfrom=billziss AT navimatics DOT com;
x-ms-exchange-messagesentrepresentingtype:	1
x-ms-office365-filtering-correlation-id:	80916bdb-c6cf-4ab3-1e92-08d3e1989e4e
x-microsoft-exchange-diagnostics:	1;CY1PR07MB2197;6:nD4nMHoyiPoIf2nnYDpjL0u0qZbFLab+MGet48lhTtZHQC8ZwE38upvWpgfOU8xWvxyToTp3J8uPH6kV0i4nlrCTfHnLXAPZXpTtZ8y694lbIS0+KH74ELeVvIYk5kvPQe0HQgMnANo2xWfegj+Y2k6OgbmKPvJMM+Kv3vOZyDO6By9VSfye1G68t7jeGcY/3SHY4FiKgz/huCBk/Yq6PoarIaKlqmmb42rVNyZs3EO6nguf2NRgwHdWw1k/BaVRS7jzRxGH4YGOZ6YpdDq9ImFnnP7F9bIEvGTvegVBMuRlW5HlQSforsFvX6E1ZAZy;5:2D5fgXgqYTfguCGBg5EQusxk5hQ1bzXslVQCVfR2Nifdzsh1s+kiYPUg8RhvREIPpy2XK1xdWrDawimFh3hhf8505la3RZ7/gtffqAYoT8Rlw+fM1+0uXg2aIijT3/js/b4NkWSa5zvJqxGX0a2I/w==;24:BATr2AxuD0X1jpUkc1ssTahFVWxEHklnCVldGipfL+1YOroXqu9GOftylwGmVrwvCG6MYAaINSRDKt+oXtstpuDDtqmaw2+bdrUTNMDghE4=;7:vwBq4wkum2ccwMZg3gJD4VYG8zTl/PpBkiGs3gYme788f7kSIcngUMS3oM5bUKS582vArK2AjKm6jAgMYtM1t0FU0GkzRohb9xn5aWpMhp8gzyMAPRLZkvmJYy3c6WhYPQwlParhdA6ddcfjYsFh2GAVe/pZdWPdpN91deJ9pcyHnpPE4hwlHgimXHQDQeIRpQpq1XchjoVS0qXP7Q65N3kTfZNLYLu+3Y1koSjnhsPKn2XlR4r0mEU8Hk1sxSSudy7Q1WU9e9iiyzjFHzassJEX3TuhozHIQjhxmU96lFHO0YIWeig5eNfFUzdUaBn9
x-microsoft-antispam:	UriScan:;BCL:0;PCL:0;RULEID:;SRVR:CY1PR07MB2197;
x-microsoft-antispam-prvs:	<CY1PR07MB2197BABF87C4D112F6FEC1D6BCF70 AT CY1PR07MB2197 DOT namprd07 DOT prod DOT outlook DOT com>
x-exchange-antispam-report-test:	UriScan:;
x-exchange-antispam-report-cfa-test:	BCL:0;PCL:0;RULEID:(6040176)(601004)(2401047)(5005006)(8121501046)(10201501046)(3002001)(6042046)(6043046);SRVR:CY1PR07MB2197;BCL:0;PCL:0;RULEID:;SRVR:CY1PR07MB2197;
x-forefront-prvs:	0071BFA85B
x-forefront-antispam-report:	SFV:NSPM;SFS:(10019020)(6009001)(7916002)(24454002)(377454003)(199003)(189002)(19580405001)(19580395003)(1730700003)(7736002)(81156014)(110136003)(6116002)(305945005)(8676002)(3846002)(87936001)(102836003)(450100001)(107886002)(2906002)(586003)(7846002)(5660300001)(5002640100001)(66066001)(97736004)(8936002)(11100500001)(81166006)(77096005)(122556002)(68736007)(189998001)(106116001)(10400500002)(106356001)(2950100001)(2900100001)(92566002)(36756003)(105586002)(99286002)(5640700001)(101416001)(93886004)(3660700001)(76176999)(54356999)(2351001)(3280700002)(2501003)(86362001)(50986999)(94096001);DIR:OUT;SFP:1102;SCL:1;SRVR:CY1PR07MB2197;H:CY1PR07MB2199.namprd07.prod.outlook.com;FPR:;SPF:None;PTR:InfoNoRecords;A:1;MX:1;LANG:en;
received-spf:	None (protection.outlook.com: navimatics.com does not designate permitted sender hosts)
spamdiagnosticoutput:	1:99
spamdiagnosticmetadata:	NSPM
MIME-Version:	1.0
X-OriginatorOrg:	navimatics.com
X-MS-Exchange-CrossTenant-originalarrivaltime:	20 Sep 2016 20:56:39.2687 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader:	Hosted
X-MS-Exchange-CrossTenant-id:	21071be9-4f9a-413b-89ac-8353a5d2410a
X-MS-Exchange-Transport-CrossTenantHeadersStamped:	CY1PR07MB2197
X-IsSubscribed:	yes
X-MIME-Autoconverted:	from base64 to 8bit by delorie.com id u8KKvECM017351

On 8/26/16, 4:59 PM, cygwin-owner AT cygwin DOT com Bill Zissimopoulos wrote:


>On 8/26/16, 11:05 AM, Corinna Vinschen wrote:
>
>>On Aug 25 19:04, Bill Zissimopoulos wrote:
>>>- The first case is during the processing of NtCreateFile (without the
>>> FILE_OPEN_REPARSE_POINT flag set).
>>
>>This case doesn't matter to us.  Cygwin always opens the file with
>>FILE_OPEN_REPARSE_POINT set...
>>
>>> - The second case is through direct manipulation of the reparse point
>>> using FSCTL_GET_REPARSE_POINT, FSCTL_SET_REPARSE_POINT and
>>> FSCTL_DELETE_REPARSE_POINT.
>>> 
>>> Let us consider the expected behavior of an NFS_SPECFILE_LNK reparse
>>>point
>>> (this is speculation) during NtCreateFile:
>>> 
>>> - On NTFS prior to Win8:
>>> 	- STATUS_IO_REPARSE_TAG_NOT_HANDLED
>>
>>...so this shouldn't happen to us, right?
>
>I think so.
>
>I will continue with the implementation/testing of reparse points and
>report back when I have more.

I have finally completed the implementation of reparse points for WinFsp.
I have also implemented NFS reparse point support for WinFsp-FUSE.

I tested this implementation with Cygwin although my testing was general
command line use and not rigorous. For this purpose I cobbled together a
patch for Cygwin; the patch is low quality and I hesitate to post it here,
but I can if so desired. Effectively I changed the implementation of
Cygwin’s mknod_worker, symlink_info::check_reparse_point and
readdir_check_reparse_point to understand and use NFS reparse points.

I am unclear on how to proceed from here. Although I do not understand the
Cygwin internals well enough and have rather limited time at the moment I
could try cleaning up the patch and officially submitting.

I am also thinking that using reparse points for POSIX special files on
other file systems that support it (i.e. NTFS) may be something that the
list should consider.

Bill

- Raw text -