X-Recipient: archive-cygwin AT delorie DOT com
X-SWARE-Spam-Status: No, hits=4.0 required=5.0	tests=AWL,BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,RCVD_IN_DNSWL_LOW
X-Spam-Check-By: sourceware.org
Received-SPF: pass (google.com: domain of nick DOT lowe AT gmail DOT com designates 10.52.27.10 as permitted sender) client-ip=10.52.27.10;
Authentication-Results: mr.google.com; spf=pass (google.com: domain of nick DOT lowe AT gmail DOT com designates 10.52.27.10 as permitted sender) smtp.mail=nick DOT lowe AT gmail DOT com; dkim=pass header.i=nick DOT lowe AT gmail DOT com
MIME-Version: 1.0
In-Reply-To: <CADSoG1so=3KxR5TS6mVNRhZGkdUku42Y=S3eWV0dtDgiZE8Tww@mail.gmail.com>
References: <CADSoG1so=3KxR5TS6mVNRhZGkdUku42Y=S3eWV0dtDgiZE8Tww AT mail DOT gmail DOT com>
Date: Tue, 21 Feb 2012 08:59:25 +0000
Message-ID: <CADSoG1uVEpxOSxAm2ZtbzE9oh95TcAQYkj_YRAZxP0tL8-3uDQ@mail.gmail.com>
Subject: shared_info::init_obcaseinsensitive implemented incorrectly
From: Nick Lowe <nick DOT lowe AT gmail DOT com>
To: cygwin AT cygwin DOT com
Content-Type: text/plain; charset=ISO-8859-1
Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
Precedence: bulk
List-Id: <cygwin.cygwin.com>
List-Unsubscribe: <mailto:cygwin-unsubscribe-archive-cygwin=delorie DOT com AT cygwin DOT 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

Dear Cygwin Developers,

shared_info::init_obcaseinsensitive in shared.cc has, in my opinion,
been implemented incorrectly.

The value of the obcaseinsensitive value in the registry only
represents how the object manager will be on next reboot and not its
present state. Cygwin uses it as if it represents the present state,
however. This is likely to be true, but is not guaranteed to be.

To determine the present state, first get the system root path via either:

1) Querying the %SystemRoot% environment variable via
RtlExpandEnvironmentStrings_U and change it with
RtlDosPathNameToNtPathName_U (alternatively
RtlDosPathNameToNtPathName_U_WithStatus in Vista and later).

2) Querying the symbolic link target of \SystemRoot via
NtQuerySymbolicLinkObject. (Requires administrative rights.)

Then, check for existence of the uppercase form of the path with
NtQueryAttributesFile ensuring, obviously, that the
OBJ_CASE_INSENSITIVE flag is not set.

If the the NTSTATUS value is successful, the object manager is running
with case insensitivity, if not its running with case sensitivity.

With regards,

Nick Lowe

--
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