From patchwork Fri Dec 20 05:23:12 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wayne Xia X-Patchwork-Id: 303895 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 2FD362C02FA for ; Fri, 20 Dec 2013 16:22:42 +1100 (EST) Received: from localhost ([::1]:47786 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VtsXn-0008OS-2c for incoming@patchwork.ozlabs.org; Fri, 20 Dec 2013 00:22:39 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41434) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VtsX4-00088U-Pc for qemu-devel@nongnu.org; Fri, 20 Dec 2013 00:22:02 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VtsWx-0007Ud-3L for qemu-devel@nongnu.org; Fri, 20 Dec 2013 00:21:54 -0500 Received: from e28smtp07.in.ibm.com ([122.248.162.7]:49677) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VtsWw-0007Tu-G9 for qemu-devel@nongnu.org; Fri, 20 Dec 2013 00:21:47 -0500 Received: from /spool/local by e28smtp07.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Fri, 20 Dec 2013 10:51:41 +0530 Received: from d28relay02.in.ibm.com (d28relay02.in.ibm.com [9.184.220.59]) by d28dlp01.in.ibm.com (Postfix) with ESMTP id 12A09E0053 for ; Fri, 20 Dec 2013 10:54:09 +0530 (IST) Received: from d28av02.in.ibm.com (d28av02.in.ibm.com [9.184.220.64]) by d28relay02.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id rBK5LX5W40304840 for ; Fri, 20 Dec 2013 10:51:33 +0530 Received: from d28av02.in.ibm.com (localhost [127.0.0.1]) by d28av02.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id rBK5LeBB022987 for ; Fri, 20 Dec 2013 10:51:40 +0530 Received: from RH64wenchao ([9.181.129.59]) by d28av02.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id rBK5LU5A021701; Fri, 20 Dec 2013 10:51:39 +0530 From: Wenchao Xia To: qemu-devel@nongnu.org Date: Fri, 20 Dec 2013 13:23:12 +0800 Message-Id: <1387516996-27531-7-git-send-email-xiawenc@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1387516996-27531-1-git-send-email-xiawenc@linux.vnet.ibm.com> References: <1387516996-27531-1-git-send-email-xiawenc@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13122005-8878-0000-0000-00000A272691 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.4.x-2.6.x [generic] X-Received-From: 122.248.162.7 Cc: kwolf@redhat.com, mdroth@linux.vnet.ibm.com, armbru@redhat.com, lcapitulino@redhat.com, Wenchao Xia Subject: [Qemu-devel] [PATCH V5 06/10] qapi script: support pre-defined enum type as discriminator in union 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org By default, any union will automatically generate a enum type as "[UnionName]Kind" in C code, and it is duplicated when the discriminator is specified as a pre-defined enum type in schema. After this patch, the pre-defined enum type will be really used as the switch case condition in generated C code, if discriminator is an enum field. Signed-off-by: Wenchao Xia Reviewed-by: Eric Blake --- docs/qapi-code-gen.txt | 8 ++++++-- scripts/qapi-types.py | 18 ++++++++++++++---- scripts/qapi-visit.py | 23 ++++++++++++++++------- scripts/qapi.py | 4 +++- 4 files changed, 39 insertions(+), 14 deletions(-) diff --git a/docs/qapi-code-gen.txt b/docs/qapi-code-gen.txt index 0728f36..a2e7921 100644 --- a/docs/qapi-code-gen.txt +++ b/docs/qapi-code-gen.txt @@ -123,11 +123,15 @@ And it looks like this on the wire: Flat union types avoid the nesting on the wire. They are used whenever a specific field of the base type is declared as the discriminator ('type' is -then no longer generated). The discriminator must always be a string field. +then no longer generated). The discriminator can be a string field or a +predefined enum field. If it is a string field, a hidden enum type will be +generated as "[UNION_NAME]Kind". If it is an enum field, a compile time check +will be done to verify the correctness. It is recommended to use an enum field. The above example can then be modified as follows: + { 'enum': 'BlockdevDriver', 'data': [ 'raw', 'qcow2' ] } { 'type': 'BlockdevCommonOptions', - 'data': { 'driver': 'str', 'readonly': 'bool' } } + 'data': { 'driver': 'BlockdevDriver', 'readonly': 'bool' } } { 'union': 'BlockdevOptions', 'base': 'BlockdevCommonOptions', 'discriminator': 'driver', diff --git a/scripts/qapi-types.py b/scripts/qapi-types.py index 914f055..5031c4b 100644 --- a/scripts/qapi-types.py +++ b/scripts/qapi-types.py @@ -201,14 +201,21 @@ def generate_union(expr): base = expr.get('base') discriminator = expr.get('discriminator') + enum_define = discriminator_find_enum_define(expr) + if enum_define: + discriminator_type_name = enum_define['enum_name'] + else: + discriminator_type_name = '%sKind' % (name) + ret = mcgen(''' struct %(name)s { - %(name)sKind kind; + %(discriminator_type_name)s kind; union { void *data; ''', - name=name) + name=name, + discriminator_type_name=discriminator_type_name) for key in typeinfo: ret += mcgen(''' @@ -389,8 +396,11 @@ for expr in exprs: fdef.write(generate_enum_lookup(expr['enum'], expr['data'])) elif expr.has_key('union'): ret += generate_fwd_struct(expr['union'], expr['data']) + "\n" - ret += generate_enum('%sKind' % expr['union'], expr['data'].keys()) - fdef.write(generate_enum_lookup('%sKind' % expr['union'], expr['data'].keys())) + enum_define = discriminator_find_enum_define(expr) + if not enum_define: + ret += generate_enum('%sKind' % expr['union'], expr['data'].keys()) + fdef.write(generate_enum_lookup('%sKind' % expr['union'], + expr['data'].keys())) if expr.get('discriminator') == {}: fdef.write(generate_anon_union_qtypes(expr)) else: diff --git a/scripts/qapi-visit.py b/scripts/qapi-visit.py index 1b55924..3240921 100644 --- a/scripts/qapi-visit.py +++ b/scripts/qapi-visit.py @@ -277,10 +277,14 @@ def generate_visit_union(expr): (key, name)) sys.exit(1) - # There will always be a discriminator in the C switch code, by default it - # is an enum type generated silently as "'%sKind' % (name)" - ret = generate_visit_enum('%sKind' % name, members.keys()) - discriminator_type_name = '%sKind' % (name) + # Use the predefined enum type as discriminator + ret = "" + discriminator_type_name = enum_define['enum_name'] + else: + # There will always be a discriminator in the C switch code, by default it + # is an enum type generated silently as "'%sKind' % (name)" + ret = generate_visit_enum('%sKind' % name, members.keys()) + discriminator_type_name = '%sKind' % (name) if base: base_fields = find_struct(base)['data'] @@ -320,11 +324,12 @@ void visit_type_%(name)s(Visitor *m, %(name)s ** obj, const char *name, Error ** else: desc_type = discriminator ret += mcgen(''' - visit_type_%(name)sKind(m, &(*obj)->kind, "%(type)s", &err); + visit_type_%(discriminator_type_name)s(m, &(*obj)->kind, "%(type)s", &err); if (!err) { switch ((*obj)->kind) { ''', - name=name, type=desc_type) + discriminator_type_name=discriminator_type_name, + type=desc_type) for key in members: if not discriminator: @@ -538,7 +543,11 @@ for expr in exprs: ret += generate_visit_list(expr['union'], expr['data']) fdef.write(ret) - ret = generate_decl_enum('%sKind' % expr['union'], expr['data'].keys()) + enum_define = discriminator_find_enum_define(expr) + ret = "" + if not enum_define: + ret = generate_decl_enum('%sKind' % expr['union'], + expr['data'].keys()) ret += generate_declaration(expr['union'], expr['data']) fdecl.write(ret) elif expr.has_key('enum'): diff --git a/scripts/qapi.py b/scripts/qapi.py index 28ede6f..50be200 100644 --- a/scripts/qapi.py +++ b/scripts/qapi.py @@ -174,7 +174,9 @@ def parse_schema(fp): add_enum(expr['enum'], expr['data']) elif expr.has_key('union'): add_union(expr) - add_enum('%sKind' % expr['union']) + enum_define = discriminator_find_enum_define(expr) + if not enum_define: + add_enum('%sKind' % expr['union']) elif expr.has_key('type'): add_struct(expr) exprs.append(expr)