[FFmpeg-devel] [PATCH 2/2] Make ff_parse_expr() and ff_parse_and_eval_expr() return an int containing an error code.

[Stefano Sabatini]

On date Thursday 2010-05-20 19:30:31 +0200, Michael Niedermayer encoded:
> On Thu, May 20, 2010 at 09:21:03AM +0200, Stefano Sabatini wrote:
> > On date Thursday 2010-05-20 03:07:08 +0200, Michael Niedermayer encoded:
> > > On Thu, May 20, 2010 at 02:08:46AM +0200, Stefano Sabatini wrote:
> > > > Allow these functions to convey to the calling application the reason
> > > > of the failure, which is not always due to a parsing error but for
> > > > example it may depend on a memory problem.
> > > 
> > > this makes the code more complex
> > > so iam not sure if this is a good idea.
> > > Could you explain what use you see in the error code?
> > 
> > I'm not very strong about this change, currently the only practical
> > use I can see is for distinguishing an invalid input error from a
> > memory error, as they are semantically two very different things, so
> > I'd prefer to allow programs to distinguish amongst the two.
> 
> then maybe pass a int *error and alow it to be NULL
> its imho more convenient, but its drifting toward bikeshed

And so I'll leave the choice to you, between these three (in my order
of preference):

1) return an int (more consistent with the rest of the API)

2) leave it as it is, this way there is no way to know if the failure
happened because of a parsing/evaluation error of because other
errors, simpler interface

3) put the error code information in an int* (expressive but somehow
inconsistent with the rest of the API).

Regards.
-- 
FFmpeg = Free and Foolish Multimedia Purposeless Ecumenical Game