From mboxrd@z Thu Jan 1 00:00:00 1970 From: Johannes Sixt Subject: Re: [PATCH] t0005: skip signal death exit code test on Windows Date: Fri, 07 Jun 2013 12:24:31 +0200 Message-ID: <51B1B4DF.90705@viscovery.net> References: <7vtxld30f2.fsf@alter.siamese.dyndns.org> <51AEE1C3.9020507@viscovery.net> <20130605071206.GC14427@sigill.intra.peff.net> <51B02D81.3000700@viscovery.net> <20130606063754.GA20050@sigill.intra.peff.net> <20130606064409.GA20334@sigill.intra.peff.net> <7vy5anyx1w.fsf@alter.siamese.dyndns.org> <20130606174032.GB32174@sigill.intra.peff.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Jeff King , Junio C Hamano , Felipe Contreras , git@vger.kernel.org To: kusmabite@gmail.com X-From: git-owner@vger.kernel.org Fri Jun 07 12:24:55 2013 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Uktqo-0005J7-E9 for gcvg-git-2@plane.gmane.org; Fri, 07 Jun 2013 12:24:54 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755250Ab3FGKYo (ORCPT ); Fri, 7 Jun 2013 06:24:44 -0400 Received: from so.liwest.at ([212.33.55.13]:47564 "EHLO so.liwest.at" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755243Ab3FGKYn (ORCPT ); Fri, 7 Jun 2013 06:24:43 -0400 Received: from [81.10.228.254] (helo=theia.linz.viscovery) by so.liwest.at with esmtpa (Exim 4.77) (envelope-from ) id 1UktqS-0005Zt-3K; Fri, 07 Jun 2013 12:24:37 +0200 Received: from [192.168.1.95] (J6T.linz.viscovery [192.168.1.95]) by theia.linz.viscovery (Postfix) with ESMTP id BE28C1660F; Fri, 7 Jun 2013 12:24:31 +0200 (CEST) User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:17.0) Gecko/20130509 Thunderbird/17.0.6 In-Reply-To: X-Enigmail-Version: 1.5.1 X-Spam-Score: -1.0 (-) Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Am 6/7/2013 12:12, schrieb Erik Faye-Lund: > On Thu, Jun 6, 2013 at 7:40 PM, Jeff King wrote: >> On Thu, Jun 06, 2013 at 10:21:47AM -0700, Junio C Hamano wrote: >> >>>> The particular deficiency is that when a signal is raise()d whose SIG_DFL >>>> action will cause process death (SIGTERM in this case), the >>>> implementation of raise() just calls exit(3). >>> >>> After a bit of web searching, it seems to me that this behaviour of >>> raise() is in msvcrt, and compat/mingw.c::mingw_raise() just calls >>> that. In other words, "the implementation of raise()" is at an even >>> lower level than mingw/msys, and I would agree that it is a platform >>> issue. >> >> Yeah, if it were mingw_raise responsible for this, I would suggest using >> the POSIX shell "128+sig" instead. We could potentially check for >> SIG_DFL[1] mingw_raise and intercept and exit there. I don't know if >> that would create headaches or confusion for other msys programs, >> though. I'd leave that up to the msysgit people to decide whether it is >> worth the trouble. >> > > ...and here's the code to do just that: > > diff --git a/compat/mingw.c b/compat/mingw.c > index b295e2f..8b3c1b4 100644 > --- a/compat/mingw.c > +++ b/compat/mingw.c > @@ -1573,7 +1573,8 @@ static HANDLE timer_event; > static HANDLE timer_thread; > static int timer_interval; > static int one_shot; > -static sig_handler_t timer_fn = SIG_DFL, sigint_fn = SIG_DFL; > +static sig_handler_t timer_fn = SIG_DFL, sigint_fn = SIG_DFL, > + sigterm_fn = SIG_DFL; > > /* The timer works like this: > * The thread, ticktack(), is a trivial routine that most of the time > @@ -1688,6 +1689,10 @@ sig_handler_t mingw_signal(int sig, > sig_handler_t handler) > sigint_fn = handler; > break; > > + case SIGTERM: > + sigterm_fn = handler; > + break; > + > default: > return signal(sig, handler); > } > @@ -1715,6 +1720,13 @@ int mingw_raise(int sig) > sigint_fn(SIGINT); > return 0; > > + case SIGTERM: > + if (sigterm_fn == SIG_DFL) > + exit(128 + SIGTERM); > + else if (sigterm_fn != SIG_IGN) > + sigterm_fn(SIGTERM); > + return 0; > + > default: > return raise(sig); > } That's pointless and does not work. The handler would only be called when raise() is called, but not when a SIGTERM is received, e.g., via Ctrl-C from the command line, because that route ends up in MSVCRT, which does not know about this handler. If you want to follow this route, you must emulate everything that MSVCRT already does for us, and that's quite a lot, in particular, when some form of thread safety is required. -- Hannes