From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 58762A04B1; Wed, 23 Sep 2020 11:43:48 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 2A1721D8FC; Wed, 23 Sep 2020 11:43:47 +0200 (CEST) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by dpdk.org (Postfix) with ESMTP id 2E3781D8CA for ; Wed, 23 Sep 2020 11:43:44 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1600854224; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=GMFNtdAZWjNTu6lNxInlwIaJDodhPXgFK+kaW2CjFbc=; b=ftTP2kaYpAH8HqYPwN/ugxdqhMexeVnoksgHVGkJ4nbalyTtkb29avHeEkLXsvy9C/PFTG TbYzupe9lJpLsJn+3zCrE1+0xjGvjMUJCxm8MJA1EKK5+BWIQK0xZR/5Hp45WQoCcCE3bS LESP73sKSR0gSZsbIqdcYhQr4li93pc= Received: from mail-vs1-f72.google.com (mail-vs1-f72.google.com [209.85.217.72]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-355-u5GrfJudOFWjvjoHRtAv5Q-1; Wed, 23 Sep 2020 05:43:43 -0400 X-MC-Unique: u5GrfJudOFWjvjoHRtAv5Q-1 Received: by mail-vs1-f72.google.com with SMTP id z25so5832484vsi.21 for ; Wed, 23 Sep 2020 02:43:42 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=GMFNtdAZWjNTu6lNxInlwIaJDodhPXgFK+kaW2CjFbc=; b=VQ0iuHugKPCer4CozOVxwhBZxNOKRyD7rWjNYROLa80MEJl+OYWA7cAagq3YxARWlu wKNJeXo1qtKVlLsZcRMCh8w6cDub2rt6Qy1oAm3zepixVd0BAY9DsVe9z7RK0uz/FN0v wKLp8m8MFTQWV80z0WK6kOF68O/wjzulCwZiplbKNrQV6Uk2qRdxpC2Dm8E4+gk3vvta pWpwp/4y8Frwe9op+iQk9ZmQeTDMsOkuhofaAS2kidTopYDGYWLT9mEf4M3eyTvWzzBE vw0U3jNRrwj1uFsOmq66oC1vgIq8rvY/ePU2mPTAiOE08fXSPPuIx9gfg5AJquqrc4/v QMZQ== X-Gm-Message-State: AOAM531d2SmEGvWGvcEo2vbU3CTp1qOvWuR64MIr6q3ZC3vE1wnbwcXa AGYMYF/67GkrmRXsquLHaM2G0ZnbrXcGHacGN2CmD/lvPy+LUcxjf5mIhEp1HyvnpWRZTMr1J+e AxdMgGC0ASjfH3kmj0t4= X-Received: by 2002:ab0:4287:: with SMTP id j7mr5412159uaj.53.1600854222528; Wed, 23 Sep 2020 02:43:42 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyZS9aZDbGvffnkjkz3woDXEEkSjEIPiu70MoUyC/RCdSNnQDRMWMsazbkggLMWeUPMAxQMkviz5QEsdcAUj1E= X-Received: by 2002:ab0:4287:: with SMTP id j7mr5412156uaj.53.1600854222317; Wed, 23 Sep 2020 02:43:42 -0700 (PDT) MIME-Version: 1.0 References: <20200922172015.266698-1-kevin.laatz@intel.com> <20200923093927.GA1757@bricha3-MOBL.ger.corp.intel.com> In-Reply-To: <20200923093927.GA1757@bricha3-MOBL.ger.corp.intel.com> From: David Marchand Date: Wed, 23 Sep 2020 11:43:31 +0200 Message-ID: To: Bruce Richardson Cc: Kevin Laatz , dev , "Yigit, Ferruh" , dpdk stable Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dmarchan@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="UTF-8" Subject: Re: [dpdk-dev] [PATCH] net/ring: fix unchecked return value X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On Wed, Sep 23, 2020 at 11:39 AM Bruce Richardson wrote: > I think a more standard way of checking for trailing chars is to use %n > which stores the number of chars processed. Then check that against > strlen. > > For example something like: > > if (sscanf(value, "%p%n", args, n) != 1 || n != strlen(value)) { > /* do error handling */ > } > The man is a bit scary about %n: The C standard says: "Execution of a %n directive does not increment the assignment count returned at the completion of execution" but the Corrigendum seems to contradict this. Probably it is wise not to make any assumptions on the effect of %n conversions on the return value. -- David Marchand