[PATCH 2/3] y2038: linux: Provide __utimes64 implementation

[Adhemerval Zanella]

On 07/02/2020 10:00, Lukasz Majewski wrote:
> This patch provides new __utimes64 explicit 64 bit function for setting file's
> 64 bit attributes for access and modification time.
> 
> Internally, the __utimensat64_helper function is used. This patch is necessary
> for having architectures with __WORDSIZE == 32 Y2038 safe.
> 
> Moreover, a 32 bit version - __utimes has been refactored to internally use
> __utimes64.
> 
> The __utimes 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 __timeval64.
> 
> 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 __utimes64 and __utimes.

LGTM with some smalls changes below.

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

> ---
>  include/time.h                   |  3 +++
>  sysdeps/unix/sysv/linux/utimes.c | 37 ++++++++++++++++++++++----------
>  2 files changed, 29 insertions(+), 11 deletions(-)
> 
> diff --git a/include/time.h b/include/time.h
> index e38f5e32e6..b04747889a 100644
> --- a/include/time.h
> +++ b/include/time.h
> @@ -211,8 +211,11 @@ libc_hidden_proto (__clock_getres64);
>  #endif
>  
>  #if __TIMESIZE == 64
> +# define __utimes64 __utimes
>  # define __utimensat64 __utimensat
>  #else
> +extern int __utimes64 (const char *file, const struct __timeval64 tvp[2]);
> +libc_hidden_proto (__utimes64)
>  extern int __utimensat64 (int fd, const char *file,
>                            const struct __timespec64 tsp[2], int flags);
>  libc_hidden_proto (__utimensat64);

Ok.

> diff --git a/sysdeps/unix/sysv/linux/utimes.c b/sysdeps/unix/sysv/linux/utimes.c
> index 121d883469..09c4e56f18 100644
> --- a/sysdeps/unix/sysv/linux/utimes.c
> +++ b/sysdeps/unix/sysv/linux/utimes.c
> @@ -16,22 +16,37 @@
>     License along with the GNU C Library; if not, see
>     <https://www.gnu.org/licenses/>.  */
>  
> -#include <errno.h>
> -#include <stddef.h>
> -#include <utime.h>
> -#include <sys/time.h>
> -#include <sysdep.h>
> +#include <time.h>
>  
> +int
> +__utimes64 (const char *file, const struct __timeval64 tvp[2])
> +{
> +  struct __timespec64 ts64[2];
> +
> +  if (tvp)

No implicit checks.

> +    {
> +      ts64[0] = timeval64_to_timespec64 (tvp[0]);
> +      ts64[1] = timeval64_to_timespec64 (tvp[1]);
> +    }
> +
> +  return __utimensat64_helper (0, file, tvp ? ts64 : NULL, 0);
> +}

Ok.

>  
> -/* Consider moving to syscalls.list.  */
> +#if __TIMESIZE != 64
> +libc_hidden_def (__utimes64)
>  
> -/* Change the access time of FILE to TVP[0] and
> -   the modification time of FILE to TVP[1].  */
>  int
>  __utimes (const char *file, const struct timeval tvp[2])
>  {
> -  /* Avoid implicit array coercion in syscall macros.  */
> -  return INLINE_SYSCALL (utimes, 2, file, &tvp[0]);
> -}
> +  struct __timeval64 tv64[2];
>  
> +  if (tvp)

No implicit checks.

> +    {
> +      tv64[0] = valid_timeval_to_timeval64 (tvp[0]);
> +      tv64[1] = valid_timeval_to_timeval64 (tvp[1]);
> +    }
> +
> +  return __utimes64 (file, tvp ? tv64 : NULL);
> +}
> +#endif
>  weak_alias (__utimes, utimes)
> 

Ok.