[PATCH v2 2/4] time: Implement c23 timespec_get base

[Joseph Myers]

On Wed, 21 Jun 2023, Yonggang Luo via Libc-alpha wrote:

>  #ifdef __USE_ISOC11
>  /* Time base values for timespec_get.  */
> -# define TIME_UTC 1
> +# define TIME_UTC                1

> +# define TIME_MONOTONIC          2
> +# define TIME_ACTIVE             3
> +# define TIME_THREAD_ACTIVE      4

These should be conditional on C2x.

> +# define TIME_MONOTONIC_RAW      5
> +# define TIME_UTC_COARSE         6
> +# define TIME_MONOTONIC_COARSE   7
> +# define TIME_BOOTTIME           8
> +# define TIME_UTC_ALARM          9
> +# define TIME_BOOTTIME_ALARM     10
> +# define TIME_SGI_CYCLE          11
> +# define TIME_TAI                12

And adding these is questionable; certainly any extension to these 
interfaces would need properly documenting (i.e. with what glibc defines 
the semantics to be, *not* what the Linux kernel defines some CLOCK_* 
semantics to be), and if added, it would be appropriate for them to be 
conditional on __USE_GNU.

> +    case TIME_BOOTTIME:
> +      clockid = CLOCK_BOOTTIME;
> +      break;
> +    case TIME_UTC_ALARM:
> +      clockid = CLOCK_REALTIME_ALARM;
> +      break;
> +    case TIME_BOOTTIME_ALARM:
> +      clockid = CLOCK_BOOTTIME_ALARM;
> +      break;

These don't exist in bits/time.h; try building for Hurd with 
build-many-glibcs.py.

> +    case TIME_SGI_CYCLE:
> +      clockid = CLOCK_SGI_CYCLE;
> +      break;

And this doesn't exist in glibc at all.  Is a Linux kernel uapi header 
included somehow?

> +    case TIME_TAI:
> +      clockid = CLOCK_TAI;
> +      break;

Again, I'd expect this to break the build for Hurd.

-- 
Joseph S. Myers
joseph@codesourcery.com