Re: [PATCH v3 6/7] y2038: linux: Provide __settimeofday64 implementation

[Adhemerval Zanella <adhemerval dot zanella at linaro dot org>]

On 29/01/2020 09:59, Lukasz Majewski wrote:
> This patch provides new __settimeofday64 explicit 64 bit function for setting
> 64 bit time in the kernel (by internally calling __clock_settime64).
> Moreover, a 32 bit version - __settimeofday has been refactored to internally
> use __settimeofday64.
> 
> The __settimeofday is now supposed to be used on systems still supporting 32
> bit time (__TIMESIZE != 64) - hence the necessary conversion of struct
> timeval to 64 bit struct __timespec64.
> 
> Internally the settimeofday uses __settimeofday64. This patch is necessary
> for having architectures with __WORDSIZE == 32 Y2038 safe.
> 
> Build tests:
> ./src/scripts/build-many-glibcs.py glibcs
> 
> Run-time tests:
> - Run specific tests on ARM/x86 32bit systems (qemu):
>   https://github.com/lmajewski/meta-y2038 and run tests:
>   https://github.com/lmajewski/y2038-tests/commits/master
> 
> Above tests were performed with Y2038 redirection applied as well as without
> to test proper usage of both __settimeofday64 and __settimeofday.
> 

LGTM, thanks.

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

> ---
> Changes for v3:
> - None
> 
> Changes for v2:
> - The conversion to support 64 bit time for settimeofday() has been moved
>   from ./time/settimeofday.c to sysdeps/unix/sysv/linux/settimeofday.c
>   (as suggested by Adhemerval) to avoid the need to create __clock_settime64()
>   method for HURD (as 64 bit time support for machines with __WORDSIZE=32
>   and __TIMESIZE=32 is now developed solely for Linux).
> ---
>  include/time.h                         |  9 +++++
>  sysdeps/unix/sysv/linux/settimeofday.c | 53 ++++++++++++++++++++++++++
>  2 files changed, 62 insertions(+)
>  create mode 100644 sysdeps/unix/sysv/linux/settimeofday.c
> 
> diff --git a/include/time.h b/include/time.h
> index 8617114052..0345803db2 100644
> --- a/include/time.h
> +++ b/include/time.h
> @@ -8,6 +8,7 @@
>  # include <time/mktime-internal.h>
>  # include <endian.h>
>  # include <time-clockid.h>
> +# include <sys/time.h>

Ok (for settimeofday).

>  
>  extern __typeof (strftime_l) __strftime_l;
>  libc_hidden_proto (__strftime_l)
> @@ -224,6 +225,14 @@ extern int __sched_rr_get_interval64 (pid_t pid, struct __timespec64 *tp);
>  libc_hidden_proto (__sched_rr_get_interval64);
>  #endif
>  
> +#if __TIMESIZE == 64
> +# define __settimeofday64 __settimeofday
> +#else
> +extern int __settimeofday64 (const struct __timeval64 *tv,
> +                             const struct timezone *tz);
> +libc_hidden_proto (__settimeofday64)
> +#endif
> +
>  /* Compute the `struct tm' representation of T,
>     offset OFFSET seconds east of UTC,
>     and store year, yday, mon, mday, wday, hour, min, sec into *TP.

Ok.

> diff --git a/sysdeps/unix/sysv/linux/settimeofday.c b/sysdeps/unix/sysv/linux/settimeofday.c
> new file mode 100644
> index 0000000000..ea45f1d7cb
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/settimeofday.c
> @@ -0,0 +1,53 @@
> +/* settimeofday -- set system time - Linux version supporting 64 bit time.
> +   Copyright (C) 2020 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#include <errno.h>
> +#include <time.h>
> +#include <sys/time.h>
> +
> +/* Set the current time of day and timezone information.
> +   This call is restricted to the super-user.  */
> +int
> +__settimeofday64 (const struct __timeval64 *tv, const struct timezone *tz)
> +{
> +  if (__glibc_unlikely (tz != 0))
> +    {
> +      if (tv != 0)
> +	{
> +	  __set_errno (EINVAL);
> +	  return -1;
> +	}
> +      return __settimezone (tz);
> +    }
> +
> +  struct __timespec64 ts = timeval64_to_timespec64 (*tv);
> +  return __clock_settime64 (CLOCK_REALTIME, &ts);
> +}
> +

Ok.

> +#if __TIMESIZE != 64
> +libc_hidden_def (__settimeofday64)
> +
> +int
> +__settimeofday (const struct timeval *tv, const struct timezone *tz)
> +{
> +  struct __timeval64 tv64 = valid_timeval_to_timeval64 (*tv);
> +
> +  return __settimeofday64 (&tv64, tz);
> +}
> +#endif
> +weak_alias (__settimeofday, settimeofday);
> 

Ok.