From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 44A38C2BBD1 for ; Thu, 17 Sep 2020 16:41:55 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 956D9206C9 for ; Thu, 17 Sep 2020 16:41:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b="h1sWkZuJ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 956D9206C9 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=igalia.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:60834 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kIwyn-0002SV-KH for qemu-devel@archiver.kernel.org; Thu, 17 Sep 2020 12:41:53 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53098) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kIwqE-0001wl-Tc; Thu, 17 Sep 2020 12:33:02 -0400 Received: from fanzine.igalia.com ([178.60.130.6]:35338) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1kIwqD-00019M-1m; Thu, 17 Sep 2020 12:33:02 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Type:MIME-Version:Message-ID:Date:References:In-Reply-To:Subject:Cc:To:From; bh=5i0goaiC1isRgsxJwWXNDDZLK0Oc/YnTnxrxLGHDrjQ=; b=h1sWkZuJNP/SZ6f000BDfCxwywtjQmddyqJvRRSFvvKfLJze2IUbHduI8+bYj+iL7qBW8opegCbB1xZ5wBKzBXPCdvRZ0q7XXb0i4s3fws2hknafRmR3XPahnKEZ4bpv4GzFnitLtfDaHON9oUDZJgKT9NrX7FvexRMUwopxuOhBkxYKiGtLLFmgzoTiaE3Jbnw/cxHTuVhC4zVTy1mSH49fa4m+XhO5s/GfKw20vUDXbCkQZL93yesmhUdOtsdk9a2HHHK1RYfO1QAN6Q3PVd+32BQAegSW/clwgxw4JT/d7cbeQj9BMPWH1ONhESzLGyhiJgnpn7c2Y41GCSJjvg==; Received: from maestria.local.igalia.com ([192.168.10.14] helo=mail.igalia.com) by fanzine.igalia.com with esmtps (Cipher TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim) id 1kIwq9-000656-7M; Thu, 17 Sep 2020 18:32:57 +0200 Received: from berto by mail.igalia.com with local (Exim) id 1kIwq8-00017z-UN; Thu, 17 Sep 2020 18:32:56 +0200 From: Alberto Garcia To: Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org Subject: Re: [PATCH 09/14] block/qcow2: qcow2_get_specific_info(): drop error propagation In-Reply-To: <20200909185930.26524-10-vsementsov@virtuozzo.com> References: <20200909185930.26524-1-vsementsov@virtuozzo.com> <20200909185930.26524-10-vsementsov@virtuozzo.com> User-Agent: Notmuch/0.18.2 (http://notmuchmail.org) Emacs/24.4.1 (i586-pc-linux-gnu) Date: Thu, 17 Sep 2020 18:32:56 +0200 Message-ID: MIME-Version: 1.0 Content-Type: text/plain Received-SPF: pass client-ip=178.60.130.6; envelope-from=berto@igalia.com; helo=fanzine.igalia.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/17 09:56:37 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x (no timestamps) [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, vsementsov@virtuozzo.com, pavel.dovgaluk@ispras.ru, qemu-devel@nongnu.org, armbru@redhat.com, groug@kaod.org, stefanha@redhat.com, pbonzini@redhat.com, mreitz@redhat.com, jsnow@redhat.com, ari@tuxera.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Wed 09 Sep 2020 08:59:25 PM CEST, Vladimir Sementsov-Ogievskiy wrote: > + * On success return true with bm_list set (probably to NULL, if no bitmaps), " probably " ? :-) > + * on failure return false with errp set. > */ > -Qcow2BitmapInfoList *qcow2_get_bitmap_info_list(BlockDriverState *bs, > - Error **errp) > +bool qcow2_get_bitmap_info_list(BlockDriverState *bs, > + Qcow2BitmapInfoList **info_list, Error **errp) > { > BDRVQcow2State *s = bs->opaque; > Qcow2BitmapList *bm_list; > Qcow2Bitmap *bm; > - Qcow2BitmapInfoList *list = NULL; > - Qcow2BitmapInfoList **plist = &list; So here 'list' points at NULL and 'plist' at &list. > - *plist = obj; > - plist = &obj->next; In the original code 'plist' is updated when you add a new element, so it always points at the end of the list. But 'list' is unchanged and it still points at the first element. So the caller receives a pointer to the first element. > + *info_list = obj; > + info_list = &obj->next; But in the new code there is only one variable (passed by the caller), which always points at the end of the list. Berto