[FFmpeg-devel] [PATCH] Implement av_strerror()

[Stefano Sabatini]

On date Sunday 2010-03-14 15:52:41 +0000, M?ns Rullg?rd encoded:
> Stefano Sabatini <stefano.sabatini-lala at poste.it> writes:
[...]
> > +int av_strerror(int errnum, char *errbuf, size_t errbuf_size)
> > +{
> > +    int ret = 0;
> > +    const char *errstr = NULL;
> > +
> > +    switch (errnum) {
> > +#define HANDLE_ERROR(ERR, ERRSTR) case AVERROR_##ERR: errstr = ERRSTR; break
> > +
> > +#if LIBAVUTIL_VERSION_MAJOR < 51
> > +        HANDLE_ERROR(IO           , "I/O error");
> > +        HANDLE_ERROR(NOENT        , "No such file or directory");
> > +        HANDLE_ERROR(NOMEM        , "Not enough memory");
> > +#endif
> > +        HANDLE_ERROR(EOF          , "End of file");
> > +        HANDLE_ERROR(INVALIDDATA  , "Invalid data found");
> > +        HANDLE_ERROR(NOFMT        , "Unknown format");
> > +        HANDLE_ERROR(NOTSUPP      , "Operation not supported");
> > +        HANDLE_ERROR(NUMEXPECTED  , "Number syntax expected in filename");
> > +        HANDLE_ERROR(PATCHWELCOME , "Not yet implemented in FFmpeg, patches welcome");
> > +    }
> 
> Please drop the macro.  It only obfuscates.

Dropeed.

> > +    if (errstr) {
> > +        av_strlcatf(errbuf, errbuf_size, errstr);
> 
> av_strlcpy()
> 
> > +    } else {
> > +#if _POSIX_C_SOURCE >= 200112L
> > +        ret = strerror_r(AVUNERROR(errnum), errbuf, errbuf_size);
> > +#else
> > +        av_strlcatf(errbuf, errbuf_size, "Error number %d", errnum);
> > +#endif
> 
> This is wrong for two reasons:
> 
> 1.  We define _POSIX_C_SOURCE to 200112.
> 2.  strerror_r() is optional.
> 
> The correct solution is to check_func it in configure.

Done like that.
-- 
FFmpeg = Frenzy Frightening Multipurpose Peaceless Extended Guru