From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49804) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eMwse-000187-Vb for qemu-devel@nongnu.org; Thu, 07 Dec 2017 09:10:32 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eMwsa-0007yI-8L for qemu-devel@nongnu.org; Thu, 07 Dec 2017 09:10:28 -0500 Received: from mx1.redhat.com ([209.132.183.28]:49714) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eMwsZ-0007wL-T3 for qemu-devel@nongnu.org; Thu, 07 Dec 2017 09:10:24 -0500 From: Markus Armbruster References: <20170911110623.24981-1-marcandre.lureau@redhat.com> <20170911110623.24981-10-marcandre.lureau@redhat.com> Date: Thu, 07 Dec 2017 15:10:12 +0100 In-Reply-To: <20170911110623.24981-10-marcandre.lureau@redhat.com> (=?utf-8?Q?=22Marc-Andr=C3=A9?= Lureau"'s message of "Mon, 11 Sep 2017 13:05:42 +0200") Message-ID: <87zi6uochn.fsf@dusky.pond.sub.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH v3 09/50] qapi: add #if/#endif helpers List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?utf-8?Q?Marc-Andr=C3=A9?= Lureau Cc: qemu-devel@nongnu.org, Michael Roth Marc-Andr=C3=A9 Lureau writes: > Add helpers to wrap generated code with #if/#endif lines. > > Add a function decorator that will be used to wrap visitor methods. > The decorator will check if code was generated before adding #if/#endif > lines. Used in the following patches. > > Signed-off-by: Marc-Andr=C3=A9 Lureau > --- > scripts/qapi.py | 55 +++++++++++++++++++++++++++++++++++++++++++++++++++= ++++ > 1 file changed, 55 insertions(+) > > diff --git a/scripts/qapi.py b/scripts/qapi.py > index 2a8e60e975..94b735d8d6 100644 > --- a/scripts/qapi.py > +++ b/scripts/qapi.py > @@ -1897,6 +1897,61 @@ def guardend(name): > name=3Dguardname(name)) >=20=20 >=20=20 > +def gen_if(ifcond): > + if not ifcond: > + return '' > + if isinstance(ifcond, str): > + ifcond =3D [ifcond] Perhaps we should take this normalization step in the QAPISchema constructors. > + ret =3D '' > + for ifc in ifcond: > + ret +=3D mcgen(''' > +#if %(cond)s > +''', cond=3Difc) > + return ret > + > + > +def gen_endif(ifcond): > + if not ifcond: > + return '' > + if isinstance(ifcond, str): > + ifcond =3D [ifcond] > + ret =3D '' > + for ifc in reversed(ifcond): > + ret +=3D mcgen(''' > +#endif /* %(cond)s */ > +''', cond=3Difc) > + return ret > + > + > +# Wrap a method to add #if / #endif to generated code, only if some > +# code was generated. The method must have an 'ifcond' argument. > +# self must have 'if_members' listing the attributes to wrap. > +def ifcond_decorator(func): > + > + def func_wrapper(self, *args, **kwargs): > + import inspect Is hiding imports in function a good idea? > + idx =3D inspect.getargspec(func).args.index('ifcond') > + ifcond =3D args[idx - 1] > + save =3D {} > + for mem in self.if_members: > + save[mem] =3D getattr(self, mem) > + func(self, *args, **kwargs) > + for mem, val in save.items(): > + newval =3D getattr(self, mem) > + if newval !=3D val: > + assert newval.startswith(val) > + newval =3D newval[len(val):] > + if newval[0] =3D=3D '\n': > + val +=3D '\n' > + newval =3D newval[1:] > + val +=3D gen_if(ifcond) > + val +=3D newval > + val +=3D gen_endif(ifcond) > + setattr(self, mem, val) > + > + return func_wrapper > + > + > def gen_enum_lookup(name, values, prefix=3DNone): > ret =3D mcgen(''' My gut feeling is still "too clever by half", but i'm reserving judgement until after review of its use, and exploration of alternatives.