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From: Markus Armbruster <armbru@redhat.com>
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Date: Wed, 17 Aug 2016 11:26:51 +0200
In-Reply-To: <20160817081706.GH14217@pxdev.xzpeter.org> (Peter Xu's message of
	"Wed, 17 Aug 2016 16:17:06 +0800")
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Subject: Re: [Qemu-devel] [PATCH 1/2] error-report: provide
 error_report_exit()
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To: Peter Xu <peterx@redhat.com>
Cc: Marcel Apfelbaum <marcel@redhat.com>, peter.maydell@linaro.org, pbonzini@redhat.com, fam@pxdev.xzpeter.org, qemu-devel@nongnu.org

Peter Xu <peterx@redhat.com> writes:

> On Tue, Aug 16, 2016 at 08:17:08PM +0800, Peter Xu wrote:
>> > > 
>> > > Also, please make it a function, not a macro:
>> > > 
>> > >     void error_report_fatal(const char *fmt, ...)
>> > >     {
>> > >         va_list ap;
>> > > 
>> > >         va_start(ap, fmt);
>> > >         error_vreport(fmt, ap);
>> > >         va_end(ap);
>> > >         exit(1);
>> > >     }
>
> Marcel (and reviewers),
>
> Now if we are having both error_report_fatal() and
> error_report_abort(), we'll write error_report() three times if we all
> take them as functions.

Yes, but all we duplicate is the usual var-arg boilerplate.

> How about we still use macro this time but leverage error_setg()
> macro as mentioned by Fam, like:
>
> +#define error_report_fatal(...) error_setg(&error_fatal, __VA_ARGS__)
> +#define error_report_abort(...) error_setg(&error_abort, __VA_ARGS__)
>
> In this case, we avoided calling exit() directly in the macro, and is
> much cleaner than writting error_report() content for three times.

I'm afraid that destroys the layering.

Currently, Error objects (util/error.c) use error reporting
(util/qemu-error.c), but not vice versa.  Their headers
(include/qapi/error.h and include/qemu/error-report.h) are idependent.
I like it that way.