From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from conssluserg-04.nifty.com (conssluserg-04.nifty.com [210.131.2.83]) by sourceware.org (Postfix) with ESMTPS id B79863858431 for ; Tue, 16 Nov 2021 08:11:18 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org B79863858431 Authentication-Results: sourceware.org; dmarc=fail (p=none dis=none) header.from=nifty.ne.jp Authentication-Results: sourceware.org; spf=fail smtp.mailfrom=nifty.ne.jp Received: from Express5800-S70 (z221123.dynamic.ppp.asahi-net.or.jp [110.4.221.123]) (authenticated) by conssluserg-04.nifty.com with ESMTP id 1AG8Avni027945 for ; Tue, 16 Nov 2021 17:10:57 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conssluserg-04.nifty.com 1AG8Avni027945 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.ne.jp; s=dec2015msa; t=1637050257; bh=YeexZZKSiND2i2t7S2jNel3UV4ALifsFudl0FJF+6g4=; h=Date:From:To:Subject:In-Reply-To:References:From; b=rC40tBieYg+2FLHA6h8fPvTxJOE8P5Lrr5nfjObXWdSFHUN5IqueavuArplOCfGNJ MHonJPM5zQ65ykWQbWjqV9k9eTbRkNRjHRpYD+9YoUu9FDXNpmLUGf+6NoyBiFOOvV ly7uP3wsy0PjMeknaQV+fgie1aRYgIiMrlKe/brxR1puzt+mMSA+BmCKRHtv0wu4Id 9eA1dcX8KKGxW5kW88nGrFk8d58OAKEYTz9rui4rMPc0zmRq8CXIvETGFsC5MvLdnN MMSr3AoMi6LVEW1MyFO15jcI9tDBYPlmYPikQ4InWa2Ee2YjE3h9iQy1+N+8iVp2LX hsmU44e0QARGA== X-Nifty-SrcIP: [110.4.221.123] Date: Tue, 16 Nov 2021 17:10:56 +0900 From: Takashi Yano To: cygwin-patches@cygwin.com Subject: Re: [PATCH] Cygwin: pipe: Handle STATUS_PENDING even for nonblocking mode. Message-Id: <20211116171056.a9f0fd202624fc25d764de25@nifty.ne.jp> In-Reply-To: <20211116031848.247-1-takashi.yano@nifty.ne.jp> References: <20211116031848.247-1-takashi.yano@nifty.ne.jp> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.30; i686-pc-mingw32) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-11.0 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, NICE_REPLY_A, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: cygwin-patches@cygwin.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Cygwin core component patch submission and discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 16 Nov 2021 08:11:22 -0000 On Tue, 16 Nov 2021 12:18:47 +0900 Takashi Yano wrote: > - NtReadFile() and NtWriteFile() seems to return STATUS_PENDING > occasionally even in nonblocking mode. This patch adds handling > for STATUS_PENDING in nonblocking mode. > > Addresses: > https://cygwin.com/pipermail/cygwin/2021-November/249910.html > --- > winsup/cygwin/fhandler_pipe.cc | 10 ++++++---- > winsup/cygwin/release/3.3.3 | 5 +++++ > 2 files changed, 11 insertions(+), 4 deletions(-) > > diff --git a/winsup/cygwin/fhandler_pipe.cc b/winsup/cygwin/fhandler_pipe.cc > index 1ebf4de10..f70ff56fe 100644 > --- a/winsup/cygwin/fhandler_pipe.cc > +++ b/winsup/cygwin/fhandler_pipe.cc > @@ -336,9 +336,10 @@ fhandler_pipe::raw_read (void *ptr, size_t& len) > break; > status = NtReadFile (get_handle (), evt, NULL, NULL, &io, ptr, > len1, NULL, NULL); > - if (evt && status == STATUS_PENDING) > + if (status == STATUS_PENDING) > { > - waitret = cygwait (evt, INFINITE, cw_cancel | cw_sig); > + HANDLE w = evt ?: get_handle (); > + waitret = cygwait (w, INFINITE, cw_cancel | cw_sig); > /* If io.Status is STATUS_CANCELLED after CancelIo, IO has actually > been cancelled and io.Information contains the number of bytes > processed so far. > @@ -507,10 +508,11 @@ fhandler_pipe_fifo::raw_write (const void *ptr, size_t len) > break; > len1 >>= 1; > } > - if (evt && status == STATUS_PENDING) > + if (status == STATUS_PENDING) > { > + HANDLE w = evt ?: get_handle (); > while (WAIT_TIMEOUT == > - (waitret = cygwait (evt, (DWORD) 0, cw_cancel | cw_sig))) > + (waitret = cygwait (w, (DWORD) 0, cw_cancel | cw_sig))) > { > if (reader_closed ()) > { > diff --git a/winsup/cygwin/release/3.3.3 b/winsup/cygwin/release/3.3.3 > index 1eb25e2fc..49c1bcdc3 100644 > --- a/winsup/cygwin/release/3.3.3 > +++ b/winsup/cygwin/release/3.3.3 > @@ -16,3 +16,8 @@ Bug Fixes > - Fix long-standing problem that new files don't get created with the > FILE_ATTRIBUTE_ARCHIVE DOS attribute set. > Addresses: https://cygwin.com/pipermail/cygwin/2021-November/249909.html > + > +- Fix issue that pipe read()/write() occationally returns a garnage > + length when NtReadFile/NtWriteFile returns STATUS_PENDING in non- > + blocking mode. > + Addresses: https://cygwin.com/pipermail/cygwin/2021-November/249910.html > -- > 2.33.0 I noticed that this patch sometimes does not work as expected. cygwaint(get_handle(), ...) may sometimes return WAIT_OBJECT_0 even when the operation is not completed. I will submit a patch according to Corinna's way. (Use event even in nonblocking mode.) -- Takashi Yano