Re: [PATCH v2 5/7] y2038: Provide conversion helpers for struct __ntptimeval64

[Adhemerval Zanella via Libc-alpha <libc-alpha@sourceware.org>]

On 08/05/2020 11:56, Lukasz Majewski wrote:
> Those functions allow easy conversion between Y2038 safe, glibc internal
> struct __ntptimeval64 and struct ntptimeval.
> 
> The reserved fields (i.e. __glibc_reserved{1234}) during conversion are
> zeroed as well, to provide behavior similar to one in ntp_gettimex function
> (where those are cleared before the struct ntptimeval is returned).
> 
> Those functions are put in Linux specific sys/timex.h file, as putting
> them into glibc's local include/time.h would cause build break on HURD as
> it doesn't support struct timex related syscalls.
> 
> Build tests:
> ./src/scripts/build-many-glibcs.py glibcs

LGTM, thanks.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

> ---
>  sysdeps/unix/sysv/linux/include/sys/timex.h | 36 +++++++++++++++++++++
>  1 file changed, 36 insertions(+)
> 
> diff --git a/sysdeps/unix/sysv/linux/include/sys/timex.h b/sysdeps/unix/sysv/linux/include/sys/timex.h
> index 8c536b9a95..e762e03230 100644
> --- a/sysdeps/unix/sysv/linux/include/sys/timex.h
> +++ b/sysdeps/unix/sysv/linux/include/sys/timex.h
> @@ -152,5 +152,41 @@ valid_timex64_to_timex (const struct __timex64 tx64)
>  
>    return tx;
>  }
> +
> +/* Convert a known valid struct ntptimeval into a struct __ntptimeval64.  */
> +static inline struct __ntptimeval64
> +valid_ntptimeval_to_ntptimeval64 (const struct ntptimeval ntv)
> +{
> +  struct __ntptimeval64 ntv64;
> +
> +  ntv64.time = valid_timeval_to_timeval64 (ntv.time);
> +  ntv64.maxerror = ntv.maxerror;
> +  ntv64.esterror = ntv.esterror;
> +  ntv64.tai = ntv.tai;
> +  ntv64.__glibc_reserved1 = 0;
> +  ntv64.__glibc_reserved2 = 0;
> +  ntv64.__glibc_reserved3 = 0;
> +  ntv64.__glibc_reserved4 = 0;
> +
> +  return ntv64;
> +}
> +

OK.

> +/* Convert a known valid struct __ntptimeval64 into a struct ntptimeval.  */
> +static inline struct ntptimeval
> +valid_ntptimeval64_to_ntptimeval (const struct __ntptimeval64 ntp64)
> +{
> +  struct ntptimeval ntp;
> +
> +  ntp.time = valid_timeval64_to_timeval (ntp64.time);
> +  ntp.maxerror = ntp64.maxerror;
> +  ntp.esterror = ntp64.esterror;
> +  ntp.tai = ntp64.tai;
> +  ntp.__glibc_reserved1 = 0;
> +  ntp.__glibc_reserved2 = 0;
> +  ntp.__glibc_reserved3 = 0;
> +  ntp.__glibc_reserved4 = 0;
> +
> +  return ntp;
> +}
>  # endif /* _ISOMAC */
>  #endif /* sys/timex.h */
> 

Ok.