Re: [PATCH 4/5] support: Add support_path_support_time64_value

[Stefan Liebler <stli@linux.ibm.com>]

On 19/03/2021 19:31, Adhemerval Zanella via Libc-alpha wrote:
> It allows to check for support on arbitrary timestamp values.
> ---
>  support/support.h                     | 11 +++++++++--
>  support/support_path_support_time64.c | 10 +++-------
>  2 files changed, 12 insertions(+), 9 deletions(-)
> 
> diff --git a/support/support.h b/support/support.h
> index 2e477c9e7c..5757c40833 100644
> --- a/support/support.h
> +++ b/support/support.h
> @@ -130,9 +130,16 @@ extern void support_copy_file (const char *from, const char *to);
>  extern ssize_t support_copy_file_range (int, off64_t *, int, off64_t *,
>  					size_t, unsigned int);
> 
> -/* Return true is PATH supports 64-bit time_t interfaces for file
> +/* Return true if PATH supports 64-bit time_t interfaces for file
>     operations (such as fstatat or utimensat).  */
> -extern bool support_path_support_time64 (const char *path);
> +extern bool support_path_support_time64_value (const char *path, int64_t at,
> +					       int64_t mt);
> +static __inline bool support_path_support_time64 (const char *path)
> +{
> +  /* 1s and 2s after y2038 limit.  */
> +  return support_path_support_time64_value (path, 0x80000001ULL,
> +					    0x80000002ULL);
> +}
> 
>  __END_DECLS
> 
> diff --git a/support/support_path_support_time64.c b/support/support_path_support_time64.c
> index 452fedcde5..33b2bdff66 100644
> --- a/support/support_path_support_time64.c
> +++ b/support/support_path_support_time64.c
> @@ -36,19 +36,15 @@ utimesat_call (const char *path, const struct __timespec64 tsp[2])
>  #endif
> 
>  bool
> -support_path_support_time64 (const char *path)
> +support_path_support_time64_value (const char *path, int64_t at, int64_t mt)
>  {
>  #ifdef __linux__
>    /* Obtain the original timestamps to restore at the end.  */
>    struct statx ostx;
>    TEST_VERIFY_EXIT (statx (AT_FDCWD, path, 0, STATX_BASIC_STATS, &ostx) == 0);
> 
> -  const struct __timespec64 tsp[] =
> -  {
> -    /* 1s and 2s after y2038 limit.  */
> -    { 0x80000001ULL, 0 },
> -    { 0x80000002ULL, 0 }
> -  };
> +  const struct __timespec64 tsp[] = { { at, 0 }, { mt, 0 } };
> +
>    /* Return is kernel does not support __NR_utimensat_time64.  */
>    if (utimesat_call (path, tsp) == -1)
>      return false;
> 
OK