From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 100150 invoked by alias); 22 Jun 2015 14:30:41 -0000 Mailing-List: contact cygwin-announce-help@cygwin.com; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-announce-owner@cygwin.com Reply-To: The Cygwin Mailing List Mail-Followup-To: cygwin-announce@cygwin.com Received: (qmail 11427 invoked by uid 89); 22 Jun 2015 12:55:22 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.8 required=5.0 tests=AWL,BAYES_50,EXECUTABLE_URI,KAM_EXEURI,KAM_LAZY_DOMAIN_SECURITY autolearn=no version=3.3.2 X-HELO: calimero.vinschen.de Date: Mon, 22 Jun 2015 14:30:00 -0000 From: Corinna Vinschen To: cygwin-announce@cygwin.com Subject: TEST RELEASE: Cygwin 2.1.0-0.2 Message-ID: <20150622125518.GF28301@calimero.vinschen.de> Mail-Followup-To: cygwin-announce@cygwin.com MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline User-Agent: Mutt/1.5.23 (2014-03-12) X-SW-Source: 2015-06/txt/msg00075.txt.bz2 Hi Cygwin friends and users, I released a second TEST version of Cygwin. The version number is 2.1.0-0.2. This test release is mostly for interested *developers*. The important news which needs some testing is the implementation of sigaltstack(2) and the underlying implementation of running a signal handler on the alternate signal stack. Two changes to the previous test release, a fix to the sys/signal.h header file which potentially broke building, and a change in the assembler code preparing the alternate stack for the signal handler. Implementation details: - The alternate signal stack installed via sigaltstack is only valid for the current thread. Each thread must call its own sigaltstack. On pthread_create, the alternate signal stack setting of the calling thread is *not* propagated to the newly created thread. This follows current Linux semantics. - The alternate signal stack is a minimal stack. Certain datastructures used by Cygwin (_cygtls area) and Windows (on 32 bit: exception records) are not copied over to the alternate signal stack. The stack settings in the Thread Environment Block (TEB) are not reflecting the current alternate stack while running the signal handler. The TEB will still point to the original thread stack. This seems to work nicely in my testing, but there may be Windows functions which stop working in this scenario. - The volatile registers and the original stack registers are stored at the base of the alternate stack. If you screw this up while running the signal handler, your thread is doomed on return to the caller. I'd be grateful if curious developers would give this new sigaltstack implementation a whirl and report back if it's working for them as desired/expected. And if not, simple reproducers in plain C are most welcome in this case. Discussing aspects of this implementation may be best handled on the cygwin-developers mailing list or the #cygwin-developers IRC channel on Freenode. All changes in this release so far: =================================== What's new: ----------- - First cut of an implementation to allow signal handlers running on an alternate signal stack. - New API sigaltstack, plus definitions for SA_ONSTACK, SS_ONSTACK, SS_DISABLE, MINSIGSTKSZ, SIGSTKSZ. - New API: sethostname. Bug Fixes --------- - Enable non-SA_RESTART behaviour on threads other than main thread. Addresses: https://cygwin.com/ml/cygwin/2015-06/msg00260.html - Try to handle concurrent close on socket more gracefully Addresses: https://cygwin.com/ml/cygwin/2015-06/msg00235.html To install 32-bit Cygwin use https://cygwin.com/setup-x86.exe To install 64 bit Cygwin use https://cygwin.com/setup-x86_64.exe Have fun, Corinna -- Corinna Vinschen Please, send mails regarding Cygwin to Cygwin Maintainer cygwin AT cygwin DOT com Red Hat