Re: [Qemu-devel] [PATCH 3/9] qapi: remove error checks for event emission

[Peter Xu <peterx@redhat.com>]

On Thu, Jul 05, 2018 at 10:43:13AM +0200, Markus Armbruster wrote:
> Peter Xu <peterx@redhat.com> writes:
> 
> > In the whole QAPI event emission code we're passing in an Error* object
> > along the whole stack.  That's never useful since it never fails after
> > all.  Remove that.
> >
> > Then, remove that parameter from all the callers to send an event.
> >
> > Suggested-by: Eric Blake <eblake@redhat.com>
> > Suggested-by: Markus Armbruster <armbru@redhat.com>
> > Signed-off-by: Peter Xu <peterx@redhat.com>
> [...]
> > diff --git a/scripts/qapi/events.py b/scripts/qapi/events.py
> > index 5657524688..3953dc9837 100644
> > --- a/scripts/qapi/events.py
> > +++ b/scripts/qapi/events.py
> > @@ -18,7 +18,7 @@ from qapi.common import *
> >  def build_event_send_proto(name, arg_type, boxed):
> >      return 'void qapi_event_send_%(c_name)s(%(param)s)' % {
> >          'c_name': c_name(name.lower()),
> > -        'param': build_params(arg_type, boxed, 'Error **errp')}
> > +        'param': build_params(arg_type, boxed, "")}
> 
> Use ' instead of " for consistency.
> 
> But let's make @extra optional in the previous patch (default it to
> None), so this spot becomes simpler.

Will do.

> 
> >  
> >  
> >  def gen_event_send_decl(name, arg_type, boxed):
> > @@ -70,7 +70,6 @@ def gen_event_send(name, arg_type, boxed, event_enum_name):
> >  %(proto)s
> >  {
> >      QDict *qmp;
> > -    Error *err = NULL;
> >      QMPEventFuncEmit emit;
> >  ''',
> >                  proto=build_event_send_proto(name, arg_type, boxed))
> > @@ -103,45 +102,35 @@ def gen_event_send(name, arg_type, boxed, event_enum_name):
> >  ''')
> >          if not arg_type.is_implicit():
> >              ret += mcgen('''
> > -    visit_type_%(c_name)s(v, "%(name)s", &arg, &err);
> > +    visit_type_%(c_name)s(v, "%(name)s", &arg, NULL);
> 
> &error_abort, please.  This should never fail, and when it does,
> something's seriously wrong.

Ok.

> 
> >  ''',
> >                           name=name, c_name=arg_type.c_name())
> >          else:
> >              ret += mcgen('''
> >  
> > -    visit_start_struct(v, "%(name)s", NULL, 0, &err);
> > -    if (err) {
> > -        goto out;
> > -    }
> > -    visit_type_%(c_name)s_members(v, &param, &err);
> > -    if (!err) {
> > -        visit_check_struct(v, &err);
> > -    }
> > +    visit_start_struct(v, "%(name)s", NULL, 0, NULL);
> > +    visit_type_%(c_name)s_members(v, &param, NULL);
> > +    visit_check_struct(v, NULL);
> 
> Likewise.

Done.  Thanks,

-- 
Peter Xu