From patchwork Mon Apr 28 15:29:37 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?T25kxZllaiBCw61sa2E=?= X-Patchwork-Id: 343477 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 47C791400BE for ; Tue, 29 Apr 2014 01:29:49 +1000 (EST) 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:mime-version :content-type; q=dns; s=default; b=PtSNqa4MTB2M/JuaEt0aAdMgvO9x0 mCNZGFcCYxkBi2OFbz2T4C0fdMcWvKNLHeMyTkJY2HhCtyXU6pzUCunvXxuyt8cu 0vTg3jONEpaNCa6hc5+l2wuXVHs9o0dwSstUpyW8qscOJfAWVeBLdiYcLvI8qXmZ d1dwZnsiu29d8s= 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:mime-version :content-type; s=default; bh=xEtGzd95kgDQrMWETG7WtrTQvQg=; b=e9v Whv+p4Ezd2G5DVIcW4444ASiqhRwfusBXQfdqaOkEvmJ8s4JDueNGxJNqqm9Fs96 qAXcxJmGoFLjLoNSeptC+YV1rEE14DQwqswvYmuVTJ+tAcMOw255ywH5iOzpZl24 M/+xz0BkIKFDDz1Ey0mAwHSqmdtGAOA2BEeBmNQs= Received: (qmail 26406 invoked by alias); 28 Apr 2014 15:29:42 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 26383 invoked by uid 89); 28 Apr 2014 15:29:42 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-0.6 required=5.0 tests=AWL, BAYES_00, FREEMAIL_FROM, SPF_NEUTRAL autolearn=no version=3.3.2 X-HELO: popelka.ms.mff.cuni.cz Date: Mon, 28 Apr 2014 17:29:37 +0200 From: =?utf-8?B?T25kxZllaiBCw61sa2E=?= To: libc-alpha@sourceware.org Subject: [PATCH][BZ 16852] Do not clobber recvmmsg argument. Message-ID: <20140428152937.GA1736@domone.podge> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.20 (2009-06-14) Hi, here Rich asked about intended behaviour of recvmmsg timeout argument. A kernel overwrites it by remaining time but we declare it with const argument. So who is correct? If we want to make timeout constant following patch should work. Comments? * sysdeps/unix/sysv/linux/recvmmsg.c (recvmmsg): Do not clobber timeout argument. diff --git a/sysdeps/unix/sysv/linux/recvmmsg.c b/sysdeps/unix/sysv/linux/recvmmsg.c index 57ddf31..56690ff 100644 --- a/sysdeps/unix/sysv/linux/recvmmsg.c +++ b/sysdeps/unix/sysv/linux/recvmmsg.c @@ -37,6 +37,10 @@ int recvmmsg (int fd, struct mmsghdr *vmessages, unsigned int vlen, int flags, const struct timespec *tmo) { + struct timespec dummy; + memcpy (&dummy, tmo, sizeof (struct timespec)); + tmo = &dummy; + if (SINGLE_THREAD_P) return INLINE_SYSCALL (recvmmsg, 5, fd, vmessages, vlen, flags, tmo); @@ -61,6 +65,10 @@ int recvmmsg (int fd, struct mmsghdr *vmessages, unsigned int vlen, int flags, const struct timespec *tmo) { + struct timespec dummy; + memcpy (&dummy, tmo, sizeof (struct timespec)); + tmo = &dummy; + if (__glibc_likely (have_recvmmsg >= 0)) { int ret = __internal_recvmmsg (fd, vmessages, vlen, flags, tmo);