Re: [Libcdio-devel] OpenBSD vs libcdio vs Audacious

[Edd Barrett]

On Sun, Jan 27, 2019 at 06:54:02PM +0100, Thomas Schmitt wrote:
> I would give set_speed_mmc() a try.

Alas, sadly this doesn't help. TBH I can live without it, although I'd
like to silence the error message unless logging is turned up.

Which brings us to:

> > I wonder if the errors should only be shown if an environment variable
> > is set or something?
> 
> You could sort the messages of lib/driver/netbsd.c into libcdio's log level
> spectrum, rather than using fprintf(stderr) or perror():
> cdio_debug(), cdio_info(), cdio_warn(), cdio_error().
> 
> (I dimly remember to have had problems when trying to enable or disable
> printing of those in the demo programs. But cdio_log_level_t in
> include/cdio/logging.h gives hope that it can be done.)

Looking at the linux driver, it seems cdio_info() would be appropriate,
but wow, the implementation of the logging functions is scary:

---8<---
void cdio_info (const char format[], ...) GNUC_PRINTF(1,2);
---8<---

And then:

--->8---
#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ > 4)
#define GNUC_PRINTF( format_idx, arg_idx )              \
  __attribute__((format (printf, format_idx, arg_idx)))
...
#else   /* !__GNUC__ */
#define GNUC_PRINTF( format_idx, arg_idx )
#endif  /* !__GNUC__ */
--->8---

So if you are not on glibc, then logging is a NOOP, by the look of it.

I'm not really sure this logging scheme can work on OpenBSD. I wonder why it
was implemented this way.

It also looks like there is no way to turn up/down the verbosity of the
logging. Or am I mistaken?

-- 
Best Regards
Edd Barrett

http://www.theunixzoo.co.uk