From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 25608 invoked by alias); 23 Jan 2014 14:10:21 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 25571 invoked by uid 89); 23 Jan 2014 14:10:18 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.0 required=5.0 tests=AWL,BAYES_00,RP_MATCHES_RCVD,SPF_HELO_PASS,SPF_PASS autolearn=ham version=3.3.2 X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Thu, 23 Jan 2014 14:10:17 +0000 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s0NEAETv007018 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 23 Jan 2014 09:10:14 -0500 Received: from brno.lan (ovpn01.gateway.prod.ext.ams2.redhat.com [10.39.146.11]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id s0NEA9qO026851; Thu, 23 Jan 2014 09:10:13 -0500 From: Pedro Alves To: gdb-patches@sourceware.org Cc: teawater@gmail.com, luis_gustavo@mentor.com Subject: [PATCH 3/5] Linux waitpid/__WALL emulation wrapper: If WNOHANG is set, don't touch sigprocmask. Date: Thu, 23 Jan 2014 14:10:00 -0000 Message-Id: <1390486209-8167-3-git-send-email-palves@redhat.com> In-Reply-To: <1390486209-8167-1-git-send-email-palves@redhat.com> References: <52E12075.3040601@redhat.com> <1390486209-8167-1-git-send-email-palves@redhat.com> X-SW-Source: 2014-01/txt/msg00895.txt.bz2 So the caller can use waitpid WNOHANG+sigsuspend. Otherwise, my_waitpid lets the SIGCHLD handler run by mistake. --- gdb/nat/linux-waitpid.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) diff --git a/gdb/nat/linux-waitpid.c b/gdb/nat/linux-waitpid.c index e9e69db..4693120 100644 --- a/gdb/nat/linux-waitpid.c +++ b/gdb/nat/linux-waitpid.c @@ -92,15 +92,19 @@ my_waitpid (int pid, int *status, int flags) wnohang = (flags & WNOHANG) != 0; flags &= ~(__WALL | __WCLONE); - flags |= WNOHANG; - /* Block all signals while here. This avoids knowing about - LinuxThread's signals. */ - sigfillset (&block_mask); - sigprocmask (SIG_BLOCK, &block_mask, &org_mask); + if (!wnohang) + { + flags |= WNOHANG; + + /* Block all signals while here. This avoids knowing about + LinuxThread's signals. */ + sigfillset (&block_mask); + sigprocmask (SIG_BLOCK, &block_mask, &org_mask); - /* ... except during the sigsuspend below. */ - sigemptyset (&wake_mask); + /* ... except during the sigsuspend below. */ + sigemptyset (&wake_mask); + } while (1) { @@ -129,7 +133,8 @@ my_waitpid (int pid, int *status, int flags) flags ^= __WCLONE; } - sigprocmask (SIG_SETMASK, &org_mask, NULL); + if (!wnohang) + sigprocmask (SIG_SETMASK, &org_mask, NULL); } else { -- 1.7.11.7