From patchwork Tue Feb 9 11:37:46 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Markus Armbruster X-Patchwork-Id: 8261491 Return-Path: X-Original-To: patchwork-qemu-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 51FAFBEEE5 for ; Tue, 9 Feb 2016 12:35:53 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 8ADEB2025A for ; Tue, 9 Feb 2016 12:35:52 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9990620251 for ; Tue, 9 Feb 2016 12:35:51 +0000 (UTC) Received: from localhost ([::1]:54706 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aT6qX-00075P-Ga for patchwork-qemu-devel@patchwork.kernel.org; Tue, 09 Feb 2016 06:52:41 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34189) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aT6cV-0007qX-Nt for qemu-devel@nongnu.org; Tue, 09 Feb 2016 06:38:16 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aT6cU-00030F-7R for qemu-devel@nongnu.org; Tue, 09 Feb 2016 06:38:11 -0500 Received: from mx1.redhat.com ([209.132.183.28]:41325) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aT6cT-000300-Uf for qemu-devel@nongnu.org; Tue, 09 Feb 2016 06:38:10 -0500 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) by mx1.redhat.com (Postfix) with ESMTPS id 926F4C0A805A for ; Tue, 9 Feb 2016 11:38:09 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-116-34.ams2.redhat.com [10.36.116.34]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u19Bc6Cc027333 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Tue, 9 Feb 2016 06:38:08 -0500 Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 225C1300BD80; Tue, 9 Feb 2016 12:38:04 +0100 (CET) From: Markus Armbruster To: qemu-devel@nongnu.org Date: Tue, 9 Feb 2016 12:37:46 +0100 Message-Id: <1455017883-25867-15-git-send-email-armbru@redhat.com> In-Reply-To: <1455017883-25867-1-git-send-email-armbru@redhat.com> References: <1455017883-25867-1-git-send-email-armbru@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 14/31] qapi: Improve generated event use of qapi visitor X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Eric Blake All other successful clients of visit_start_struct() were paired with an unconditional visit_end_struct(); but the generated code for events was relying on qmp_output_visitor_cleanup() to work on an incomplete visit. Alter the code to guarantee that the struct is completed, which will make a future patch to split visit_end_struct() easier to reason about. While at it, drop some assertions and comments that are not present in other uses of the qmp output visitor, and pass NULL rather than "" as the 'kind' parameter (matching most other uses where obj is NULL). The changes to the generated code look like: | qmp = qmp_event_build_dict("DEVICE_TRAY_MOVED"); | | qov = qmp_output_visitor_new(); |- g_assert(qov); |- | v = qmp_output_get_visitor(qov); |- g_assert(v); | |- /* Fake visit, as if all members are under a structure */ |- visit_start_struct(v, NULL, "", "DEVICE_TRAY_MOVED", 0, &err); |+ visit_start_struct(v, NULL, NULL, "DEVICE_TRAY_MOVED", 0, &err); | if (err) { | goto out; | } | visit_type_str(v, (char **)&device, "device", &err); | if (err) { |- goto out; |+ goto out_obj; | } | visit_type_bool(v, &tray_open, "tray-open", &err); | if (err) { |- goto out; |+ goto out_obj; | } |- visit_end_struct(v, &err); |+out_obj: |+ visit_end_struct(v, err ? NULL : &err); | if (err) { | goto out; | } | | obj = qmp_output_get_qobject(qov); |- g_assert(obj != NULL); |+ g_assert(obj); | | qdict_put_obj(qmp, "data", obj); | emit(QAPI_EVENT_DEVICE_TRAY_MOVED, qmp, &err); Note that the 'goto out_obj' with no intervening code before the label, as well as the construct of 'err ? NULL : &err', are both a bit unusual but also temporary; they get fixed in a later patch that splits visit_end_struct() to drop its errp parameter by moving some checking before the label. But until that time, this was the simplest way to avoid the appearance of passing a possibly-set error to visit_end_struct(), even though actual code inspection shows that visit_end_struct() for a QMP output visitor will never set an error. Signed-off-by: Eric Blake Message-Id: <1454075341-13658-11-git-send-email-eblake@redhat.com> [Commit message's code diff tweaked] Signed-off-by: Markus Armbruster --- scripts/qapi-event.py | 16 +++++++--------- scripts/qapi.py | 5 +++-- 2 files changed, 10 insertions(+), 11 deletions(-) diff --git a/scripts/qapi-event.py b/scripts/qapi-event.py index 720486f..0f5534f 100644 --- a/scripts/qapi-event.py +++ b/scripts/qapi-event.py @@ -2,7 +2,7 @@ # QAPI event generator # # Copyright (c) 2014 Wenchao Xia -# Copyright (c) 2015 Red Hat Inc. +# Copyright (c) 2015-2016 Red Hat Inc. # # Authors: # Wenchao Xia @@ -61,25 +61,23 @@ def gen_event_send(name, arg_type): if arg_type and arg_type.members: ret += mcgen(''' qov = qmp_output_visitor_new(); - g_assert(qov); - v = qmp_output_get_visitor(qov); - g_assert(v); - /* Fake visit, as if all members are under a structure */ - visit_start_struct(v, NULL, "", "%(name)s", 0, &err); + visit_start_struct(v, NULL, NULL, "%(name)s", 0, &err); ''', name=name) ret += gen_err_check() - ret += gen_visit_fields(arg_type.members, need_cast=True) + ret += gen_visit_fields(arg_type.members, need_cast=True, + label='out_obj') ret += mcgen(''' - visit_end_struct(v, &err); +out_obj: + visit_end_struct(v, err ? NULL : &err); if (err) { goto out; } obj = qmp_output_get_qobject(qov); - g_assert(obj != NULL); + g_assert(obj); qdict_put_obj(qmp, "data", obj); ''') diff --git a/scripts/qapi.py b/scripts/qapi.py index 0f032c3..9254e48 100644 --- a/scripts/qapi.py +++ b/scripts/qapi.py @@ -1636,7 +1636,8 @@ def gen_err_check(label='out', skiperr=False): label=label) -def gen_visit_fields(members, prefix='', need_cast=False, skiperr=False): +def gen_visit_fields(members, prefix='', need_cast=False, skiperr=False, + label='out'): ret = '' if skiperr: errparg = 'NULL' @@ -1664,7 +1665,7 @@ def gen_visit_fields(members, prefix='', need_cast=False, skiperr=False): c_type=memb.type.c_name(), prefix=prefix, cast=cast, c_name=c_name(memb.name), name=memb.name, errp=errparg) - ret += gen_err_check(skiperr=skiperr) + ret += gen_err_check(skiperr=skiperr, label=label) if memb.optional: pop_indent()