[v6,1/3] y2038: include: Move struct __timespec64 definition to a separate file

The struct __timespec64's definition has been moved from ./include/time.h to
./include/struct___timespec64.h.

This change would prevent from polluting other glibc namespaces (when
headers are modified to support 64 bit time on architectures with
__WORDSIZE==32).

Now it is possible to just include definition of this particular structure
when needed.

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

---
Changes for v6:
- Add _STRUCT_TIMESPEC64_H guard instead of _TIMESPEC64
- Fix preprocessor directives indentation

Changes for v5:
- Move struct___timespec64.h from include/bits/types to include

Changes for v4:
- None

Changes for v3:
- Rebase to the newest glibc's - master

Changes for v2:
- New patch - as suggested by Andreas Schwab
---
 include/struct___timespec64.h | 27 +++++++++++++++++++++++++++
 include/time.h                | 24 +-----------------------
 2 files changed, 28 insertions(+), 23 deletions(-)
 create mode 100644 include/struct___timespec64.h

On 31/03/2020 05:35, Lukasz Majewski wrote:
> The struct __timespec64's definition has been moved from ./include/time.h to
> ./include/struct___timespec64.h.
> 
> This change would prevent from polluting other glibc namespaces (when
> headers are modified to support 64 bit time on architectures with
> __WORDSIZE==32).
> 
> Now it is possible to just include definition of this particular structure
> when needed.
> 
> Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

Still LGTM, thanks.

> 
> ---
> Changes for v6:
> - Add _STRUCT_TIMESPEC64_H guard instead of _TIMESPEC64
> - Fix preprocessor directives indentation
> 
> Changes for v5:
> - Move struct___timespec64.h from include/bits/types to include
> 
> Changes for v4:
> - None
> 
> Changes for v3:
> - Rebase to the newest glibc's - master
> 
> Changes for v2:
> - New patch - as suggested by Andreas Schwab
> ---
>  include/struct___timespec64.h | 27 +++++++++++++++++++++++++++
>  include/time.h                | 24 +-----------------------
>  2 files changed, 28 insertions(+), 23 deletions(-)
>  create mode 100644 include/struct___timespec64.h
> 
> diff --git a/include/struct___timespec64.h b/include/struct___timespec64.h
> new file mode 100644
> index 0000000000..9abb25c8f7
> --- /dev/null
> +++ b/include/struct___timespec64.h
> @@ -0,0 +1,27 @@
> +#ifndef _STRUCT_TIMESPEC64_H
> +#define _STRUCT_TIMESPEC64_H
> +
> +#if __TIMESIZE == 64
> +# define __timespec64 timespec
> +#else
> +#include <endian.h>
> +/* The glibc Y2038-proof struct __timespec64 structure for a time value.
> +   To keep things Posix-ish, we keep the nanoseconds field a 32-bit
> +   signed long, but since the Linux field is a 64-bit signed int, we
> +   pad our tv_nsec with a 32-bit unnamed bit-field padding.
> +
> +   As a general rule the Linux kernel is ignoring upper 32 bits of
> +   tv_nsec field.  */
> +struct __timespec64
> +{
> +  __time64_t tv_sec;         /* Seconds */
> +# if BYTE_ORDER == BIG_ENDIAN
> +  __int32_t :32;             /* Padding */
> +  __int32_t tv_nsec;         /* Nanoseconds */
> +# else
> +  __int32_t tv_nsec;         /* Nanoseconds */
> +  __int32_t :32;             /* Padding */
> +# endif
> +};
> +#endif
> +#endif /* _STRUCT_TIMESPEC64_H  */
> diff --git a/include/time.h b/include/time.h
> index 4522fe9c4f..1c103a4cb2 100644
> --- a/include/time.h
> +++ b/include/time.h
> @@ -3,11 +3,11 @@
>  
>  #ifndef _ISOMAC
>  # include <bits/types/struct_timeval.h>
> +# include <struct___timespec64.h>
>  # include <bits/types/locale_t.h>
>  # include <stdbool.h>
>  # include <time/mktime-internal.h>
>  # include <sys/time.h>
> -# include <endian.h>
>  # include <time-clockid.h>
>  # include <sys/time.h>
>  
> @@ -61,28 +61,6 @@ extern void __tzset_parse_tz (const char *tz) attribute_hidden;
>  extern void __tz_compute (__time64_t timer, struct tm *tm, int use_localtime)
>    __THROW attribute_hidden;
>  
> -#if __TIMESIZE == 64
> -# define __timespec64 timespec
> -#else
> -/* The glibc Y2038-proof struct __timespec64 structure for a time value.
> -   To keep things Posix-ish, we keep the nanoseconds field a 32-bit
> -   signed long, but since the Linux field is a 64-bit signed int, we
> -   pad our tv_nsec with a 32-bit unnamed bit-field padding.
> -
> -   As a general rule the Linux kernel is ignoring upper 32 bits of
> -   tv_nsec field.  */
> -struct __timespec64
> -{
> -  __time64_t tv_sec;         /* Seconds */
> -# if BYTE_ORDER == BIG_ENDIAN
> -  __int32_t :32;             /* Padding */
> -  __int32_t tv_nsec;         /* Nanoseconds */
> -# else
> -  __int32_t tv_nsec;         /* Nanoseconds */
> -  __int32_t :32;             /* Padding */
> -# endif
> -};
> -#endif
>  
>  #if __TIMESIZE == 64
>  # define __itimerspec64 itimerspec
>