From patchwork Tue May 3 14:55:26 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hanna Czenczek X-Patchwork-Id: 12836109 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 8D9CAC433FE for ; Tue, 3 May 2022 19:46:51 +0000 (UTC) Received: from localhost ([::1]:46508 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nlyTy-0004x2-Gz for qemu-devel@archiver.kernel.org; Tue, 03 May 2022 15:46:50 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:37410) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nlyQL-0007gO-Ul for qemu-devel@nongnu.org; Tue, 03 May 2022 15:43:05 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:55190) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nlyQG-0001Yt-2I for qemu-devel@nongnu.org; Tue, 03 May 2022 15:43:05 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1651606975; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=AsLwc0WzmagZVTZ7m/+iyLFqXRi9tQCnpaz66vDCpIE=; b=FcvC9YY2ukLKcdN7y7ZbTbgcOaaXosBX1ugj6UhLqm+gdYHkBBA9komjIomuE47MDIkGy9 5Q58ghnPipSIiDnF37iRcmp/vepOpXsLer8VM7UVoEo1RS6sY4iJWLx3CHHT6hQQWgJoFM fuRsPwyOKY1BA/FK1ThQdXezvNiMXKY= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-551-_bAikI1CPrW5SyxDFIz8OA-1; Tue, 03 May 2022 11:10:55 -0400 X-MC-Unique: _bAikI1CPrW5SyxDFIz8OA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 3EFC23D4F445; Tue, 3 May 2022 14:55:32 +0000 (UTC) Received: from localhost (unknown [10.39.193.124]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E95ED40D2820; Tue, 3 May 2022 14:55:31 +0000 (UTC) From: Hanna Reitz To: qemu-block@nongnu.org Cc: qemu-devel@nongnu.org, Hanna Reitz , Kevin Wolf , Markus Armbruster , Eric Blake Subject: [PATCH 1/4] block: Improve empty format-specific info dump Date: Tue, 3 May 2022 16:55:26 +0200 Message-Id: <20220503145529.37070-2-hreitz@redhat.com> In-Reply-To: <20220503145529.37070-1-hreitz@redhat.com> References: <20220503145529.37070-1-hreitz@redhat.com> MIME-Version: 1.0 Content-type: text/plain X-Scanned-By: MIMEDefang 2.84 on 10.11.54.2 Received-SPF: pass client-ip=170.10.133.124; envelope-from=hreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" When a block driver supports obtaining format-specific information, but that object only contains optional fields, it is possible that none of them are present, so that dump_qobject() (called by bdrv_image_info_specific_dump()) will not print anything. The callers of bdrv_image_info_specific_dump() put a header above this information ("Format specific information:\n"), which will look strange when there is nothing below. Modify bdrv_image_info_specific_dump() to print this header instead of its callers, and only if there is indeed something to be printed. Signed-off-by: Hanna Reitz Reviewed-by: Kevin Wolf --- include/block/qapi.h | 3 ++- block/qapi.c | 41 +++++++++++++++++++++++++++++++++++++---- qemu-io-cmds.c | 4 ++-- 3 files changed, 41 insertions(+), 7 deletions(-) diff --git a/include/block/qapi.h b/include/block/qapi.h index 22c7807c89..c09859ea78 100644 --- a/include/block/qapi.h +++ b/include/block/qapi.h @@ -40,6 +40,7 @@ void bdrv_query_image_info(BlockDriverState *bs, Error **errp); void bdrv_snapshot_dump(QEMUSnapshotInfo *sn); -void bdrv_image_info_specific_dump(ImageInfoSpecific *info_spec); +void bdrv_image_info_specific_dump(ImageInfoSpecific *info_spec, + const char *prefix); void bdrv_image_info_dump(ImageInfo *info); #endif diff --git a/block/qapi.c b/block/qapi.c index cf557e3aea..51202b470a 100644 --- a/block/qapi.c +++ b/block/qapi.c @@ -777,7 +777,35 @@ static void dump_qdict(int indentation, QDict *dict) } } -void bdrv_image_info_specific_dump(ImageInfoSpecific *info_spec) +/* + * Return whether dumping the given QObject with dump_qobject() would + * yield an empty dump, i.e. not print anything. + */ +static bool qobject_is_empty_dump(const QObject *obj) +{ + switch (qobject_type(obj)) { + case QTYPE_QNUM: + case QTYPE_QSTRING: + case QTYPE_QBOOL: + return false; + + case QTYPE_QDICT: + return qdict_size(qobject_to(QDict, obj)) == 0; + + case QTYPE_QLIST: + return qlist_empty(qobject_to(QList, obj)); + + default: + abort(); + } +} + +/** + * Dumps the given ImageInfoSpecific object in a human-readable form, + * prepending an optional prefix if the dump is not empty. + */ +void bdrv_image_info_specific_dump(ImageInfoSpecific *info_spec, + const char *prefix) { QObject *obj, *data; Visitor *v = qobject_output_visitor_new(&obj); @@ -785,7 +813,12 @@ void bdrv_image_info_specific_dump(ImageInfoSpecific *info_spec) visit_type_ImageInfoSpecific(v, NULL, &info_spec, &error_abort); visit_complete(v, &obj); data = qdict_get(qobject_to(QDict, obj), "data"); - dump_qobject(1, data); + if (!qobject_is_empty_dump(data)) { + if (prefix) { + qemu_printf("%s", prefix); + } + dump_qobject(1, data); + } qobject_unref(obj); visit_free(v); } @@ -866,7 +899,7 @@ void bdrv_image_info_dump(ImageInfo *info) } if (info->has_format_specific) { - qemu_printf("Format specific information:\n"); - bdrv_image_info_specific_dump(info->format_specific); + bdrv_image_info_specific_dump(info->format_specific, + "Format specific information:\n"); } } diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c index 2f0d8ac25a..084ec44d3b 100644 --- a/qemu-io-cmds.c +++ b/qemu-io-cmds.c @@ -1819,8 +1819,8 @@ static int info_f(BlockBackend *blk, int argc, char **argv) return -EIO; } if (spec_info) { - printf("Format specific information:\n"); - bdrv_image_info_specific_dump(spec_info); + bdrv_image_info_specific_dump(spec_info, + "Format specific information:\n"); qapi_free_ImageInfoSpecific(spec_info); }