From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48988) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WLTdw-0006Aq-0P for qemu-devel@nongnu.org; Thu, 06 Mar 2014 03:27:10 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WLTdq-0007OW-1a for qemu-devel@nongnu.org; Thu, 06 Mar 2014 03:27:03 -0500 Received: from mx1.redhat.com ([209.132.183.28]:7047) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WLTdp-0007OS-Oi for qemu-devel@nongnu.org; Thu, 06 Mar 2014 03:26:57 -0500 From: Markus Armbruster References: <1393987480-37579-1-git-send-email-wenchaoqemu@gmail.com> Date: Thu, 06 Mar 2014 09:26:51 +0100 In-Reply-To: <1393987480-37579-1-git-send-email-wenchaoqemu@gmail.com> (Wenchao Xia's message of "Tue, 4 Mar 2014 18:44:30 -0800") Message-ID: <87txbbbulw.fsf@blackfin.pond.sub.org> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Qemu-devel] [PATCH V9 00/10] qapi script: support enum as discriminator and better enum name List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Wenchao Xia Cc: kwolf@redhat.com, lcapitulino@redhat.com, qemu-devel@nongnu.org, mdroth@linux.vnet.ibm.com Wenchao Xia writes: > This series address two issues: > > 1. support using enum as discriminator in union. > For example, if we have following define in qapi schema: > { 'enum': 'EnumOne', > 'data': [ 'value1', 'value2', 'value3' ] } > > { 'type': 'UserDefBase0', > 'data': { 'base-string0': 'str', 'base-enum0': 'EnumOne' } } > > Before this series, discriminator in union must be a string, and a > hidden enum type as discriminator is generated. After this series, > qapi schema can directly use predefined enum type: > { 'union': 'UserDefEnumDiscriminatorUnion', > 'base': 'UserDefBase0', > 'discriminator' : 'base-enum0', > 'data': { 'value1' : 'UserDefA', > 'value2' : 'UserDefInherit', > 'value3' : 'UserDefB' } } > > The benefit is that every thing is defined explicitly in schema file, > the discriminator enum type can be used in other API define in schema, > and a compile time check will be put to verify the correctness according > to enum define. Currently BlockdevOptions used discriminator which can > be converted, in the future other union can also use enum discriminator. > > The implement is done by: > 1.1 remember the enum defines by qapi scripts.(patch 1) > 1.2 use the remembered enum define to check correctness at compile > time.(patch 3), more strict check(patch 2) > 1.3 use the same enum name generation rule to avoid C code mismatch, > esp for "case [ENUM_VALUE]" in qapi-visit.c.(patch 4,5) > 1.4 switch the code path, when pre-defined enum type is used as discriminator, > don't generate a hidden enum type, use the enum type instead, add > docs/qapi-code-gen.txt.(Patch 6) > 1.5 test case shows how it looks like.(Patch 7) > 1.6 convert BlockdevOptions. (Patch 8) > > 2. Better enum name generation > Before this patch, AIOContext->A_I_O_CONTEXT, after this patch, > AIOContet->AIO_CONTEXT. Since previous patch has foldered enum > name generation codes into one function, it is done easily by modifying > it.(Patch 9) Applies cleanly to master. We're down to a single, simple question on PATCH 07/10.