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=ZVBW7OKAzzbHpbGhdMT6iFgTij8uBppdCJ/u7RFIWEIg2bubBmXnk
	g+rSf6+ixwP9A7XLOwpqv9iRZRsAOVxzrlcRAz7dUiwIr28WMSUOJUeZzQdFeSP3
	HRFrOwMAhhdg7HH76RNm2ICsCX4v8u/PE0XD0Gs3AOReUK6bL1LI6Y=
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=XOYRFr7vPjGm9O/qcQ79O171ylc=; b=igwKpe0TuVwrJ8sy2fjYiWXmOz57
	lidOeUtqqjh0aVCMf4cVvdr4zHLXHwAd80TqqJiuMDkBZJANyH2lWnLpmSW8XxY9
	Yo3HIqsJjrqpzbXfNsfKZjkKZ2aSJUGeEVf8xjHk39BHF6SYRhjOtAvnpN7E4PRc
	7VsWjPMN1V5wdhw=
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=-4.9 required=5.0 tests=AWL,BAYES_00,UNSUBSCRIBE_BODY autolearn=no version=3.3.2
X-HELO:	calimero.vinschen.de
Date:	Wed, 4 Mar 2015 13:19:52 +0100
From:	Corinna Vinschen <corinna-cygwin AT cygwin DOT com>
To:	cygwin AT cygwin DOT com
Subject:	Re: Cygwin hangs up if several keys are typed during outputting a lot of texts.
Message-ID:	<20150304121952.GL3213@calimero.vinschen.de>
Reply-To:	cygwin AT cygwin DOT com
Mail-Followup-To:	cygwin AT cygwin DOT com
References:	<20150228144019 DOT 0e4cfdb3a26bfac361b538e2 AT nifty DOT ne DOT jp> <20150228140251 DOT GA11124 AT calimero DOT vinschen DOT de> <20150302204502 DOT 39b3e03ad5084b0b5add5d10 AT nifty DOT ne DOT jp> <20150302144426 DOT GK3213 AT calimero DOT vinschen DOT de> <20150304203407 DOT 14008531b0fb63ad5c19a33f AT nifty DOT ne DOT jp>
MIME-Version:	1.0
In-Reply-To:	<20150304203407.14008531b0fb63ad5c19a33f@nifty.ne.jp>
User-Agent:	Mutt/1.5.23 (2014-03-12)

--VcZjVMblxkg0/8Ur
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On Mar  4 20:34, Takashi Yano wrote:
> On Mon, 2 Mar 2015 15:44:26 +0100
> Corinna Vinschen <corinna-cygwin AT cygwin DOT com> wrote:
>=20
> > > 1) Buffer of named pipe gets full-filled by a lot of data written
> > >   by slave side.
> > > 2) WriteFile() in fhandler_pty_master::doecho(), which is called
> > >   from master side by key input, is blocked because the buffer
> > >   is full.
> > > 3) If a handling to read from the pipe is in the same thread as
> > >   key input, the thread falls into deadlock.
> > >=20
> > > To check buffer space before WriteFile() is one idea,
> > > but it is not smart, I suppose...
> >=20
> > I think that's not it.  For testing I added code to convert the
> > WriteFile calls in fhandler_pty_slave::write, fhandler_pty_master::doec=
ho
> > and fhandler_pty_slave::write to overlapped I/O and made sure to wait
> > for the result after the output mutex has been released.
> >=20
> > This change has no effect at all.  Looks like this needs some more
> > digging.
>=20
> Hmm.
>=20
> To confirm my assumption, I have modified the TTY code
> for testing. The modification is shown in an attached
> diff-file against current CVS version. (Note that this
> patch is not for fixing the problem. It is for just a
> testing.)
>=20
> With this modification, half of buffer is kept empty
> for fhandler_pty_master::doecho(). I assumed the blocking
> could be avoided because buffer is always free.
>=20
> As a result of the test, it has become clear that this
> modification conceals the problem. This means the problem
> is closely related to occupancy of buffer.
>=20
> Now, I suppose the cause has been clarified. So we have
> to work out a solution. How can we resolve this problem?

I'm not sure.  I still have to look deeper into that.  Locally
I treid to woraround this problem by calling WriteFile overlapped
without waiting for the result, but even that doesn't work.

Hmm,
Corinna

--=20
Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Maintainer                 cygwin AT cygwin DOT com
Red Hat

--VcZjVMblxkg0/8Ur
Content-Type: application/pgp-signature

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
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=DOTX
-----END PGP SIGNATURE-----

--VcZjVMblxkg0/8Ur--

- Raw text -