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:date:from:to:subject:message-id:reply-to
	:references:mime-version:content-type:in-reply-to; q=dns; s=
	default; b=aWk5kxqrMHPo1SGPk5a4J2eSXDkpEPeg1IE2oDoRgcyXeQ8CYImG+
	2GXYgsM6N+JoVLbTKgRO8sr0e/9kicWQTLd7j2EnBfrw73B/+wQwNs7l8jjQvHjh
	NhFpGJvyV0ZGuL/xgPkKgnlEc1G9lhSsVpQuzCl9N2dtA6xYFX3eoM=
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:date:from:to:subject:message-id:reply-to
	:references:mime-version:content-type:in-reply-to; s=default;
	bh=ItmYeQI3cMmg1OCG9ij8dndJ7tw=; b=BAfkb0YJPXGTtUST1ElHLNSS1Tnr
	vc7UxOmj9/yhvovquNzQ6q9bLLCiEOyZ7pmg8mDp6YVDFWTrHU63PYE0CtU5nXhc
	83vh3UmAhS3rmWIzQAXyepC0440+7r7LdOZ4WG7ab/Lzz/6/YYya0I+1XCbUnIL9
	j8PCenbCXni6yIY=
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
X-Spam-SWARE-Status:	No, score=-1.9 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_NONE,RCVD_IN_HOSTKARMA_YE autolearn=ham version=3.3.1
X-Mail-Handler:	Dyn Standard SMTP by Dyn
X-Report-Abuse-To:	abuse AT dyndns DOT com (see http://www.dyndns.com/services/sendlabs/outbound_abuse.html for abuse reporting information)
X-MHO-User:	U2FsdGVkX18pz8pvF5qj3v8PpS61w2/b
Date:	Tue, 11 Jun 2013 10:20:02 -0400
From:	Christopher Faylor <cgf-use-the-mailinglist-please AT cygwin DOT com>
To:	cygwin AT cygwin DOT com
Subject:	Re: [PATCH] Check for existence of the path before processing '..'
Message-ID:	<20130611142002.GA1927@ednor.casa.cgf.cx>
Reply-To:	cygwin AT cygwin DOT com
Mail-Followup-To:	cygwin AT cygwin DOT com
References:	<001401ce66a4$bb9029a0$32b07ce0$%fedin AT samsung DOT com>
MIME-Version:	1.0
In-Reply-To:	<001401ce66a4$bb9029a0$32b07ce0$%fedin@samsung.com>
User-Agent:	Mutt/1.5.20 (2009-06-14)

On Tue, Jun 11, 2013 at 05:08:13PM +0400, Fedin Pavel wrote:
> Hello!
>
> Some time ago i reported ability to access things like
>"/usr/nonexistent/..bin". I still had this problem and i tried my hands on
>fixing it.
> The patch works by checking the actual existence of the path before
>removing the last component from it. For performance reasons, only one check
>is done for things like "../..". Because, obviously, if "/foo/bar/baz"
>exists, then "/foo/bar" exists too. Also, the check is done only after some
>components have been added to the path. So, for example, current directory
>(obtained when processing relative paths), will not be checked.
> I tried to add a similar test also to normalize_win32_path() function,
>however this broke things like "cd /usr/src/..". For some reason, a POSIX
>version of the path (but with reversed slashes) is passed to this routine
>when expanding mount points, so, consequently, test for "\usr\src" using
>GetFileType() fails.
> I think it's ok, at least POSIX paths now behave in POSIX way. I have
>tested against performance, there is some loss (~0.2 seconds), but only for
>referencing '..'.
> With this patch i am able to compile the latest version of glibc with no
>problems.

You introduce a check_parent flag which is set every time a non-slash
character is found.  That doesn't seem right.  It seems like it should
be set whenever you see a slash.

Also you are calling path_conv recursively.  I assume that is where you
are seeing a performance hit.

cgf

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

- Raw text -