[v2,13/25] y2038: Use a common definition for stat

From: Lukasz Majewski <lukma@denx.de>

Instead of replicate the same definitions from struct_stat_time64.h
on the multiple struct_stat.h, use a common header which is included
when required (struct_stat_time64_helper.h).  The 64-bit time support
is added only for LFS support.

The __USE_TIME_BITS64 is not defined internally yet, although the
internal header is used when building the 64-bit stat implementations.
---
 sysdeps/unix/sysv/linux/Makefile              |  3 +-
 sysdeps/unix/sysv/linux/bits/struct_stat.h    | 51 ++++++-----
 .../linux/bits/struct_stat_time64_helper.h    | 63 +++++++++++++
 .../unix/sysv/linux/m68k/bits/struct_stat.h   | 50 ++++++-----
 .../sysv/linux/microblaze/bits/struct_stat.h  | 48 ++++++----
 .../unix/sysv/linux/mips/bits/struct_stat.h   | 89 ++++++++++--------
 .../sysv/linux/powerpc/bits/struct_stat.h     | 52 ++++++-----
 .../unix/sysv/linux/s390/bits/struct_stat.h   | 56 +++++++-----
 sysdeps/unix/sysv/linux/struct_stat_time64.h  | 59 +-----------
 .../unix/sysv/linux/x86/bits/struct_stat.h    | 90 ++++++++++---------
 10 files changed, 317 insertions(+), 244 deletions(-)
 create mode 100644 sysdeps/unix/sysv/linux/bits/struct_stat_time64_helper.h

On 5/18/21 4:56 PM, Adhemerval Zanella wrote:
> From: Lukasz Majewski <lukma@denx.de>
> 
> Instead of replicate the same definitions from struct_stat_time64.h
> on the multiple struct_stat.h, use a common header which is included
> when required (struct_stat_time64_helper.h).  The 64-bit time support
> is added only for LFS support.
> 
> The __USE_TIME_BITS64 is not defined internally yet, although the
> internal header is used when building the 64-bit stat implementations.

Requesting a v3 please.

Please add the __glibc_reserved* members to the structures to preserve
maximum compatibility with the kernel structure.

See review of patch 14/25 for more general details.

I am almost OK with this change as-is because in general everyone
should be using statx at this point with the ability to extend and
provide more information.

However because the kernel contains:

 24 struct stat {
 25         unsigned long   st_dev;         /* Device.  */
 26         unsigned long   st_ino;         /* File serial number.  */
 27         unsigned int    st_mode;        /* File mode.  */
 28         unsigned int    st_nlink;       /* Link count.  */
 29         unsigned int    st_uid;         /* User ID of the file's owner.  */
 30         unsigned int    st_gid;         /* Group ID of the file's group. */
 31         unsigned long   st_rdev;        /* Device number, if device.  */
 32         unsigned long   __pad1;
 33         long            st_size;        /* Size of file, in bytes.  */
 34         int             st_blksize;     /* Optimal block size for I/O.  */
 35         int             __pad2;
 36         long            st_blocks;      /* Number 512-byte blocks allocated. */
 37         long            st_atime;       /* Time of last access.  */
 38         unsigned long   st_atime_nsec;
 39         long            st_mtime;       /* Time of last modification.  */
 40         unsigned long   st_mtime_nsec;
 41         long            st_ctime;       /* Time of last status change.  */
 42         unsigned long   st_ctime_nsec;
 43         unsigned int    __unused4;
 44         unsigned int    __unused5;
 45 };

With __unused4 and __unused5. I think we should match this ABI as closely as we can
to avoid future compatibility issues with legacy APIs.

> ---
>  sysdeps/unix/sysv/linux/Makefile              |  3 +-
>  sysdeps/unix/sysv/linux/bits/struct_stat.h    | 51 ++++++-----
>  .../linux/bits/struct_stat_time64_helper.h    | 63 +++++++++++++
>  .../unix/sysv/linux/m68k/bits/struct_stat.h   | 50 ++++++-----
>  .../sysv/linux/microblaze/bits/struct_stat.h  | 48 ++++++----
>  .../unix/sysv/linux/mips/bits/struct_stat.h   | 89 ++++++++++--------
>  .../sysv/linux/powerpc/bits/struct_stat.h     | 52 ++++++-----
>  .../unix/sysv/linux/s390/bits/struct_stat.h   | 56 +++++++-----
>  sysdeps/unix/sysv/linux/struct_stat_time64.h  | 59 +-----------
>  .../unix/sysv/linux/x86/bits/struct_stat.h    | 90 ++++++++++---------
>  10 files changed, 317 insertions(+), 244 deletions(-)
>  create mode 100644 sysdeps/unix/sysv/linux/bits/struct_stat_time64_helper.h
> 
> diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile
> index e28f6470e3..f83f147ed1 100644
> --- a/sysdeps/unix/sysv/linux/Makefile
> +++ b/sysdeps/unix/sysv/linux/Makefile
> @@ -100,7 +100,8 @@ sysdep_headers += sys/mount.h sys/acct.h \
>  		  bits/types/struct_msqid_ds.h \
>  		  bits/types/struct_shmid_ds.h \
>  		  bits/ipc-perm.h \
> -		  bits/struct_stat.h
> +		  bits/struct_stat.h \
> +		  bits/struct_stat_time64_helper.h

OK. Add new helper header.

>  
>  tests += tst-clone tst-clone2 tst-clone3 tst-fanotify tst-personality \
>  	 tst-quota tst-sync_file_range tst-sysconf-iov_max tst-ttyname \
> diff --git a/sysdeps/unix/sysv/linux/bits/struct_stat.h b/sysdeps/unix/sysv/linux/bits/struct_stat.h
> index b852ee256e..ba41f86142 100644
> --- a/sysdeps/unix/sysv/linux/bits/struct_stat.h
> +++ b/sysdeps/unix/sysv/linux/bits/struct_stat.h
> @@ -28,32 +28,35 @@
>  
>  struct stat
>    {
> +#ifdef __USE_TIME_BITS64
> +# include <bits/struct_stat_time64_helper.h>

OK. Use helper.

> +#else
>      __dev_t st_dev;			/* Device.  */
>      unsigned short int __pad1;
> -#ifndef __USE_FILE_OFFSET64
> +# ifndef __USE_FILE_OFFSET64
>      __ino_t st_ino;			/* File serial number.	*/
> -#else
> +# else
>      __ino_t __st_ino;			/* 32bit file serial number.	*/
> -#endif
> +# endif
>      __mode_t st_mode;			/* File mode.  */
>      __nlink_t st_nlink;			/* Link count.  */
>      __uid_t st_uid;			/* User ID of the file's owner.	*/
>      __gid_t st_gid;			/* Group ID of the file's group.*/
>      __dev_t st_rdev;			/* Device number, if device.  */
>      unsigned short int __pad2;
> -#ifndef __USE_FILE_OFFSET64
> +# ifndef __USE_FILE_OFFSET64
>      __off_t st_size;			/* Size of file, in bytes.  */
> -#else
> +# else
>      __off64_t st_size;			/* Size of file, in bytes.  */
> -#endif
> +# endif
>      __blksize_t st_blksize;		/* Optimal block size for I/O.  */
>  
> -#ifndef __USE_FILE_OFFSET64
> +# ifndef __USE_FILE_OFFSET64
>      __blkcnt_t st_blocks;		/* Number 512-byte blocks allocated. */
> -#else
> +# else
>      __blkcnt64_t st_blocks;		/* Number 512-byte blocks allocated. */
> -#endif
> -#ifdef __USE_XOPEN2K8
> +# endif
> +# ifdef __USE_XOPEN2K8
>      /* Nanosecond resolution timestamps are stored in a format
>         equivalent to 'struct timespec'.  This is the type used
>         whenever possible but the Unix namespace rules do not allow the
> @@ -63,28 +66,32 @@ struct stat
>      struct timespec st_atim;		/* Time of last access.  */
>      struct timespec st_mtim;		/* Time of last modification.  */
>      struct timespec st_ctim;		/* Time of last status change.  */
> -# define st_atime st_atim.tv_sec	/* Backward compatibility.  */
> -# define st_mtime st_mtim.tv_sec
> -# define st_ctime st_ctim.tv_sec
> -#else
> +#  define st_atime st_atim.tv_sec	/* Backward compatibility.  */
> +#  define st_mtime st_mtim.tv_sec
> +#  define st_ctime st_ctim.tv_sec
> +# else
>      __time_t st_atime;			/* Time of last access.  */
>      unsigned long int st_atimensec;	/* Nscecs of last access.  */
>      __time_t st_mtime;			/* Time of last modification.  */
>      unsigned long int st_mtimensec;	/* Nsecs of last modification.  */
>      __time_t st_ctime;			/* Time of last status change.  */
>      unsigned long int st_ctimensec;	/* Nsecs of last status change.  */
> -#endif
> -#ifndef __USE_FILE_OFFSET64
> +# endif
> +# ifndef __USE_FILE_OFFSET64
>      unsigned long int __glibc_reserved4;
>      unsigned long int __glibc_reserved5;
> -#else
> +# else
>      __ino64_t st_ino;			/* File serial number.	*/
> -#endif
> +# endif
> +#endif /* __USE_TIME_BITS64  */
>    };
>  
>  #ifdef __USE_LARGEFILE64
>  struct stat64
>    {
> +# ifdef __USE_TIME_BITS64
> +#  include <bits/struct_stat_time64_helper.h>
> +# else
>      __dev_t st_dev;			/* Device.  */
>      unsigned int __pad1;
>  
> @@ -99,7 +106,7 @@ struct stat64
>      __blksize_t st_blksize;		/* Optimal block size for I/O.  */
>  
>      __blkcnt64_t st_blocks;		/* Number 512-byte blocks allocated. */
> -# ifdef __USE_XOPEN2K8
> +#  ifdef __USE_XOPEN2K8
>      /* Nanosecond resolution timestamps are stored in a format
>         equivalent to 'struct timespec'.  This is the type used
>         whenever possible but the Unix namespace rules do not allow the
> @@ -109,15 +116,16 @@ struct stat64
>      struct timespec st_atim;		/* Time of last access.  */
>      struct timespec st_mtim;		/* Time of last modification.  */
>      struct timespec st_ctim;		/* Time of last status change.  */
> -# else
> +#  else
>      __time_t st_atime;			/* Time of last access.  */
>      unsigned long int st_atimensec;	/* Nscecs of last access.  */
>      __time_t st_mtime;			/* Time of last modification.  */
>      unsigned long int st_mtimensec;	/* Nsecs of last modification.  */
>      __time_t st_ctime;			/* Time of last status change.  */
>      unsigned long int st_ctimensec;	/* Nsecs of last status change.  */
> -# endif
> +#  endif
>      __ino64_t st_ino;			/* File serial number.		*/
> +# endif /* __USE_TIME_BITS64  */

OK. Reindent.

>    };
>  #endif
>  
> @@ -127,5 +135,4 @@ struct stat64
>  /* Nanosecond resolution time values are supported.  */
>  #define _STATBUF_ST_NSEC
>  
> -

Please avoid spurious empty line removal when not related to the patch at hand.

>  #endif /* _BITS_STRUCT_STAT_H  */
> diff --git a/sysdeps/unix/sysv/linux/bits/struct_stat_time64_helper.h b/sysdeps/unix/sysv/linux/bits/struct_stat_time64_helper.h
> new file mode 100644
> index 0000000000..77385e9073
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/bits/struct_stat_time64_helper.h
> @@ -0,0 +1,63 @@
> +/* Definition for helper to define struct stat with 64 bit time.

OK.

> +   Copyright (C) 2021 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/>.  */
> +

Reviewing...

> +  /* Content of internal __stat64_t64 struct.  */
> +  __dev_t st_dev;		/* Device.  */

OK.

> +  __ino64_t st_ino;		/* file serial number.	*/

OK.

> +  __mode_t st_mode;		/* File mode.  */

OK.

> +  __nlink_t st_nlink;		/* Link count.  */

OK.

> +  __uid_t st_uid;		/* User ID of the file's owner.  */
> +  __gid_t st_gid;		/* Group ID of the file's group.  */

OK uid/gid.

> +  __dev_t st_rdev;		/* Device number, if device.  */

OK.

> +  __off64_t st_size;		/* Size of file, in bytes.  */

OK.

> +  __blksize_t st_blksize;	/* Optimal block size for I/O.  */
> +  __blkcnt64_t st_blocks;	/* Number 512-byte blocks allocated. */

OK.

Plase add __glibc_reserved4 and __glibc_reserved5 here.

> +#ifdef __USE_XOPEN2K8
> +# ifndef __struct_timespec
> +#  define __struct_timespec struct timespec
> +# endif
> +  /* Nanosecond resolution timestamps are stored in a format
> +     equivalent to 'struct timespec'.  This is the type used
> +     whenever possible but the Unix namespace rules do not allow the
> +     identifier 'timespec' to appear in the <sys/stat.h> header.
> +     Therefore we have to handle the use of this header in strictly
> +     standard-compliant sources special.  */
> +  __struct_timespec st_atim;
> +  __struct_timespec st_mtim;
> +  __struct_timespec st_ctim;
> +# define st_atime st_atim.tv_sec
> +# define st_mtime st_mtim.tv_sec
> +# define st_ctime st_ctim.tv_sec
> +# undef __struct_timespec

OK.

> +#else
> +/* The definition should be equal to the 'struct __timespec64' internal
> +   layout.  */
> +# if __BYTE_ORDER == __BIG_ENDIAN
> +#  define __fieldts64(name)					\
> +   __time64_t name; __int32_t :32; __int32_t name ## nsec
> +# else
> +#  define __fieldts64(name)					\
> +   __time64_t name; __int32_t name ## nsec; __int32_t :32
> +# endif
> +
> +  __fieldts64 (st_atime);
> +  __fieldts64 (st_mtime);
> +  __fieldts64 (st_ctime);

OK.

> +
> +# undef __fieldts64
> +#endif
> diff --git a/sysdeps/unix/sysv/linux/m68k/bits/struct_stat.h b/sysdeps/unix/sysv/linux/m68k/bits/struct_stat.h
> index 4ae7506eb5..0512ecc3bc 100644
> --- a/sysdeps/unix/sysv/linux/m68k/bits/struct_stat.h
> +++ b/sysdeps/unix/sysv/linux/m68k/bits/struct_stat.h
> @@ -25,32 +25,35 @@
>  
>  struct stat
>    {
> +#ifdef __USE_TIME_BITS64
> +# include <bits/struct_stat_time64_helper.h>

OK. Use helper.

> +#else
>      __dev_t st_dev;			/* Device.  */
>      unsigned short int __pad1;
> -#ifndef __USE_FILE_OFFSET64
> +# ifndef __USE_FILE_OFFSET64
>      __ino_t st_ino;			/* File serial number.	*/
> -#else
> +# else
>      __ino_t __st_ino;			/* 32bit file serial number.	*/
> -#endif
> +# endif
>      __mode_t st_mode;			/* File mode.  */
>      __nlink_t st_nlink;			/* Link count.  */
>      __uid_t st_uid;			/* User ID of the file's owner.	*/
>      __gid_t st_gid;			/* Group ID of the file's group.*/
>      __dev_t st_rdev;			/* Device number, if device.  */
>      unsigned short int __pad2;
> -#ifndef __USE_FILE_OFFSET64
> +# ifndef __USE_FILE_OFFSET64
>      __off_t st_size;			/* Size of file, in bytes.  */
> -#else
> +# else
>      __off64_t st_size;			/* Size of file, in bytes.  */
> -#endif
> +# endif
>      __blksize_t st_blksize;		/* Optimal block size for I/O.  */
>  
> -#ifndef __USE_FILE_OFFSET64
> +# ifndef __USE_FILE_OFFSET64
>      __blkcnt_t st_blocks;		/* Number 512-byte blocks allocated. */
> -#else
> +# else
>      __blkcnt64_t st_blocks;		/* Number 512-byte blocks allocated. */
> -#endif
> -#ifdef __USE_XOPEN2K8
> +# endif
> +# ifdef __USE_XOPEN2K8
>      /* Nanosecond resolution timestamps are stored in a format
>         equivalent to 'struct timespec'.  This is the type used
>         whenever possible but the Unix namespace rules do not allow the
> @@ -60,28 +63,32 @@ struct stat
>      struct timespec st_atim;		/* Time of last access.  */
>      struct timespec st_mtim;		/* Time of last modification.  */
>      struct timespec st_ctim;		/* Time of last status change.  */
> -# define st_atime st_atim.tv_sec	/* Backward compatibility.  */
> -# define st_mtime st_mtim.tv_sec
> -# define st_ctime st_ctim.tv_sec
> -#else
> +#  define st_atime st_atim.tv_sec	/* Backward compatibility.  */
> +#  define st_mtime st_mtim.tv_sec
> +#  define st_ctime st_ctim.tv_sec
> +# else
>      __time_t st_atime;			/* Time of last access.  */
>      unsigned long int st_atimensec;	/* Nscecs of last access.  */
>      __time_t st_mtime;			/* Time of last modification.  */
>      unsigned long int st_mtimensec;	/* Nsecs of last modification.  */
>      __time_t st_ctime;			/* Time of last status change.  */
>      unsigned long int st_ctimensec;	/* Nsecs of last status change.  */
> -#endif
> -#ifndef __USE_FILE_OFFSET64
> +# endif
> +# ifndef __USE_FILE_OFFSET64
>      unsigned long int __glibc_reserved4;
>      unsigned long int __glibc_reserved5;
> -#else
> +# else
>      __ino64_t st_ino;			/* File serial number.	*/
> -#endif
> +# endif
> +#endif /* __USE_TIME_BITS64  */
>    };
>  
>  #ifdef __USE_LARGEFILE64
>  struct stat64
>    {
> +# ifdef __USE_TIME_BITS64
> +#  include <bits/struct_stat_time64_helper.h>

OK. Use helper again.

> +# else
>      __dev_t st_dev;			/* Device.  */
>      unsigned short int __pad1;
>  
> @@ -96,7 +103,7 @@ struct stat64
>      __blksize_t st_blksize;		/* Optimal block size for I/O.  */
>  
>      __blkcnt64_t st_blocks;		/* Number 512-byte blocks allocated. */
> -# ifdef __USE_XOPEN2K8
> +#  ifdef __USE_XOPEN2K8
>      /* Nanosecond resolution timestamps are stored in a format
>         equivalent to 'struct timespec'.  This is the type used
>         whenever possible but the Unix namespace rules do not allow the
> @@ -106,15 +113,16 @@ struct stat64
>      struct timespec st_atim;		/* Time of last access.  */
>      struct timespec st_mtim;		/* Time of last modification.  */
>      struct timespec st_ctim;		/* Time of last status change.  */
> -# else
> +#  else
>      __time_t st_atime;			/* Time of last access.  */
>      unsigned long int st_atimensec;	/* Nscecs of last access.  */
>      __time_t st_mtime;			/* Time of last modification.  */
>      unsigned long int st_mtimensec;	/* Nsecs of last modification.  */
>      __time_t st_ctime;			/* Time of last status change.  */
>      unsigned long int st_ctimensec;	/* Nsecs of last status change.  */
> -# endif
> +#  endif
>      __ino64_t st_ino;			/* File serial number.		*/
> +# endif /* __USE_TIME_BITS64 */
>    };
>  #endif
>  
> diff --git a/sysdeps/unix/sysv/linux/microblaze/bits/struct_stat.h b/sysdeps/unix/sysv/linux/microblaze/bits/struct_stat.h
> index be1bdc3557..0284d4b2b2 100644
> --- a/sysdeps/unix/sysv/linux/microblaze/bits/struct_stat.h
> +++ b/sysdeps/unix/sysv/linux/microblaze/bits/struct_stat.h
> @@ -26,6 +26,9 @@
>  #ifndef __USE_FILE_OFFSET64
>  struct stat
>  {
> +#ifdef __USE_TIME_BITS64
> +# include <bits/struct_stat_time64_helper.h>

OK. Use helper.

> +#else
>          __dev_t         st_dev;     /* Device.  */
>          __ino_t         st_ino;     /* File serial number.  */
>          __mode_t        st_mode;    /* File mode.  */
> @@ -38,7 +41,7 @@ struct stat
>          __blksize_t     st_blksize; /* Optimal block size for I/O.  */
>          int             __pad3;
>          __blkcnt_t      st_blocks;  /* Number 512-byte blocks allocated.  */
> -#ifdef __USE_XOPEN2K8
> +# ifdef __USE_XOPEN2K8
>          /* Nanosecond resolution timestamps are stored in a format
>           * equivalent to 'struct timespec'. This is the type used
>           * whenever possible but the Unix namespace rules do not allow the
> @@ -48,19 +51,20 @@ struct stat
>          struct timespec         st_atim; /* Time of last access.  */
>          struct timespec         st_mtim; /* Time of last modification.  */
>          struct timespec         st_ctim; /* Time of last status change.  */
> -# define st_atime st_atim.tv_sec         /* Backward compatibility.  */
> -# define st_mtime st_mtim.tv_sec
> -# define st_ctime st_ctim.tv_sec
> -#else
> +#  define st_atime st_atim.tv_sec         /* Backward compatibility.  */
> +#  define st_mtime st_mtim.tv_sec
> +#  define st_ctime st_ctim.tv_sec
> +# else
>          __time_t                st_atime;     /* Time of last access.  */
>          unsigned long int       st_atimensec; /* Nscecs of last access.  */
>          __time_t                st_mtime;     /* Time of last modification.  */
>          unsigned long int       st_mtimensec; /* Nsecs of last modification.  */
>          __time_t                st_ctime;     /* Time of last status change.  */
>          unsigned long int       st_ctimensec; /* Nsecs of last status change.  */
> -#endif
> +# endif
>          unsigned int            __glibc_reserved4;
>          unsigned int            __glibc_reserved5;
> +#endif /* __USE_TIME_BITS64  */
>  };
>  #else /* __USE_FILE_OFFSET64 */
>  /* MS: If __USE_FILE_OFFSET64 is setup then struct stat should match stat64
> @@ -70,6 +74,9 @@ struct stat
>   * create one ifdef to separate stats structures.  */
>  struct stat
>  {
> +#ifdef __USE_TIME_BITS64
> +# include <bits/struct_stat_time64_helper.h>

OK. Use helper.

> +#else
>          unsigned long long      st_dev;     /* Device.  */
>          __ino64_t               st_ino;     /* 32bit file serial number.  */
>          __mode_t                st_mode;    /* File mode.  */
> @@ -82,7 +89,7 @@ struct stat
>          __blksize_t             st_blksize; /* Optimal block size for I/O.  */
>          int                     __pad3;
>          __blkcnt64_t            st_blocks;  /* Number 512-byte blocks allocated.  */
> -#ifdef __USE_MISC
> +# ifdef __USE_MISC
>          /* Nanosecond resolution timestamps are stored in a format
>           * equivalent to 'struct timespec'. This is the type used
>           * whenever possible but the Unix namespace rules do not allow the
> @@ -92,25 +99,29 @@ struct stat
>          struct timespec         st_atim;      /* Time of last access.  */
>          struct timespec         st_mtim;      /* Time of last modification.  */
>          struct timespec         st_ctim;      /* Time of last status change.  */
> -# define st_atime st_atim.tv_sec              /* Backward compatibility.  */
> -# define st_mtime st_mtim.tv_sec
> -# define st_ctime st_ctim.tv_sec
> -#else
> +#  define st_atime st_atim.tv_sec              /* Backward compatibility.  */
> +#  define st_mtime st_mtim.tv_sec
> +#  define st_ctime st_ctim.tv_sec
> +# else
>          __time_t                st_atime;     /* Time of last access.  */
>          unsigned long int       st_atimensec; /* Nscecs of last access.  */
>          __time_t                st_mtime;     /* Time of last modification.  */
>          unsigned long int       st_mtimensec; /* Nsecs of last modification.  */
>          __time_t                st_ctime;     /* Time of last status change.  */
>          unsigned long int       st_ctimensec; /* Nsecs of last status change.  */
> -#endif
> +# endif
>          unsigned int            __glibc_reserved4;
>          unsigned int            __glibc_reserved5;
> +# endif /* __USE_TIME_BITS64 */
>  };
>  #endif /* __USE_FILE_OFFSET64 */
>  
>  #ifdef __USE_LARGEFILE64
>  struct stat64
>  {
> +# ifdef __USE_TIME_BITS64
> +#  include <bits/struct_stat_time64_helper.h>

OK. Use helper.

> +# else
>          unsigned long long      st_dev;     /* Device.  */
>          __ino64_t               st_ino;     /* 32bit file serial number.  */
>          __mode_t                st_mode;    /* File mode.  */
> @@ -123,7 +134,7 @@ struct stat64
>          __blksize_t             st_blksize; /* Optimal block size for I/O.  */
>          int                     __pad3;
>          __blkcnt64_t            st_blocks;  /* Number 512-byte blocks allocated.  */
> -#ifdef __USE_XOPEN2K8
> +#  ifdef __USE_XOPEN2K8
>          /* Nanosecond resolution timestamps are stored in a format
>           * equivalent to 'struct timespec'. This is the type used
>           * whenever possible but the Unix namespace rules do not allow the
> @@ -133,19 +144,20 @@ struct stat64
>          struct timespec         st_atim;    /* Time of last access.  */
>          struct timespec         st_mtim;    /* Time of last modification.  */
>          struct timespec         st_ctim;    /* Time of last status change.  */
> -# define st_atime st_atim.tv_sec            /* Backward compatibility.  */
> -# define st_mtime st_mtim.tv_sec
> -# define st_ctime st_ctim.tv_sec
> -#else
> +#   define st_atime st_atim.tv_sec           /* Backward compatibility.  */
> +#   define st_mtime st_mtim.tv_sec
> +#   define st_ctime st_ctim.tv_sec
> +#  else
>          __time_t                st_atime;     /* Time of last access.  */
>          unsigned long int       st_atimensec; /* Nscecs of last access.  */
>          __time_t                st_mtime;     /* Time of last modification.  */
>          unsigned long int       st_mtimensec; /* Nsecs of last modification.  */
>          __time_t                st_ctime;     /* Time of last status change.  */
>          unsigned long int       st_ctimensec; /* Nsecs of last status change.  */
> -#endif
> +#  endif
>          unsigned int            __glibc_reserved4;
>          unsigned int            __glibc_reserved5;
> +# endif /* __USE_TIME_BITS64 */
>  };
>  #endif
>  
> diff --git a/sysdeps/unix/sysv/linux/mips/bits/struct_stat.h b/sysdeps/unix/sysv/linux/mips/bits/struct_stat.h
> index 7ae4c10827..ab9f474cbc 100644
> --- a/sysdeps/unix/sysv/linux/mips/bits/struct_stat.h
> +++ b/sysdeps/unix/sysv/linux/mips/bits/struct_stat.h
> @@ -29,28 +29,31 @@
>  /* Structure describing file characteristics.  */
>  struct stat
>    {
> +# ifdef __USE_TIME_BITS64
> +#  include <bits/struct_stat_time64_helper.h>

OK. Use helper.

> +# else
>      unsigned long int st_dev;
>      long int st_pad1[3];
> -#ifndef __USE_FILE_OFFSET64
> +#  ifndef __USE_FILE_OFFSET64
>      __ino_t st_ino;		/* File serial number.		*/
> -#else
> +#  else
>      __ino64_t st_ino;		/* File serial number.		*/
> -#endif
> +#  endif
>      __mode_t st_mode;		/* File mode.  */
>      __nlink_t st_nlink;		/* Link count.  */
>      __uid_t st_uid;		/* User ID of the file's owner.	*/
>      __gid_t st_gid;		/* Group ID of the file's group.*/
>      unsigned long int st_rdev;	/* Device number, if device.  */
> -#ifndef __USE_FILE_OFFSET64
> +#  ifndef __USE_FILE_OFFSET64
>      long int st_pad2[2];
>      __off_t st_size;		/* Size of file, in bytes.  */
>      /* SVR4 added this extra long to allow for expansion of off_t.  */
>      long int st_pad3;
> -#else
> +#  else
>      long int st_pad2[3];
>      __off64_t st_size;		/* Size of file, in bytes.  */
> -#endif
> -#ifdef __USE_XOPEN2K8
> +#  endif
> +#  ifdef __USE_XOPEN2K8
>      /* Nanosecond resolution timestamps are stored in a format
>         equivalent to 'struct timespec'.  This is the type used
>         whenever possible but the Unix namespace rules do not allow the
> @@ -60,30 +63,34 @@ struct stat
>      struct timespec st_atim;            /* Time of last access.  */
>      struct timespec st_mtim;            /* Time of last modification.  */
>      struct timespec st_ctim;            /* Time of last status change.  */
> -# define st_atime st_atim.tv_sec        /* Backward compatibility.  */
> -# define st_mtime st_mtim.tv_sec
> -# define st_ctime st_ctim.tv_sec
> -#else
> +#   define st_atime st_atim.tv_sec        /* Backward compatibility.  */
> +#   define st_mtime st_mtim.tv_sec
> +#   define st_ctime st_ctim.tv_sec
> +#  else
>      __time_t st_atime;			/* Time of last access.  */
>      unsigned long int st_atimensec;	/* Nscecs of last access.  */
>      __time_t st_mtime;			/* Time of last modification.  */
>      unsigned long int st_mtimensec;	/* Nsecs of last modification.  */
>      __time_t st_ctime;			/* Time of last status change.  */
>      unsigned long int st_ctimensec;	/* Nsecs of last status change.  */
> -#endif
> +#  endif
>      __blksize_t st_blksize;	/* Optimal block size for I/O.  */
> -#ifndef __USE_FILE_OFFSET64
> +#  ifndef __USE_FILE_OFFSET64
>      __blkcnt_t st_blocks;	/* Number of 512-byte blocks allocated.  */
> -#else
> +#  else
>      long int st_pad4;
>      __blkcnt64_t st_blocks;	/* Number of 512-byte blocks allocated.  */
> -#endif
> +#  endif
>      long int st_pad5[14];
> +# endif /* __USE_TIME_BITS64  */
>    };
>  
> -#ifdef __USE_LARGEFILE64
> +# ifdef __USE_LARGEFILE64
>  struct stat64
>    {
> +#  ifdef __USE_TIME_BITS64
> +#   include <bits/struct_stat_time64_helper.h>

OK. Use helper.

> +#  else
>      unsigned long int st_dev;
>      long int st_pad1[3];
>      __ino64_t st_ino;		/* File serial number.		*/
> @@ -94,7 +101,7 @@ struct stat64
>      unsigned long int st_rdev;	/* Device number, if device.  */
>      long int st_pad2[3];
>      __off64_t st_size;		/* Size of file, in bytes.  */
> -# ifdef __USE_XOPEN2K8
> +#   ifdef __USE_XOPEN2K8
>      /* Nanosecond resolution timestamps are stored in a format
>         equivalent to 'struct timespec'.  This is the type used
>         whenever possible but the Unix namespace rules do not allow the
> @@ -104,44 +111,47 @@ struct stat64
>      struct timespec st_atim;            /* Time of last access.  */
>      struct timespec st_mtim;            /* Time of last modification.  */
>      struct timespec st_ctim;            /* Time of last status change.  */
> -# else
> +#   else
>      __time_t st_atime;			/* Time of last access.  */
>      unsigned long int st_atimensec;	/* Nscecs of last access.  */
>      __time_t st_mtime;			/* Time of last modification.  */
>      unsigned long int st_mtimensec;	/* Nsecs of last modification.  */
>      __time_t st_ctime;			/* Time of last status change.  */
>      unsigned long int st_ctimensec;	/* Nsecs of last status change.  */
> -# endif
> +#   endif
>      __blksize_t st_blksize;	/* Optimal block size for I/O.  */
>      long int st_pad3;
>      __blkcnt64_t st_blocks;	/* Number of 512-byte blocks allocated.  */
>      long int st_pad4[14];
> +#  endif /* __USE_TIME_BITS64  */
>    };
> -#endif
> -#else
> +# endif /* __USE_LARGEFILE64  */
> +
> +#else /* _MIPS_SIM != _ABIO32  */
> +
>  struct stat
>    {
>      __dev_t st_dev;
>      int	st_pad1[3];		/* Reserved for st_dev expansion  */
> -#ifndef __USE_FILE_OFFSET64
> +# ifndef __USE_FILE_OFFSET64
>      __ino_t st_ino;
> -#else
> +# else
>      __ino64_t st_ino;
> -#endif
> +# endif
>      __mode_t st_mode;
>      __nlink_t st_nlink;
>      __uid_t st_uid;
>      __gid_t st_gid;
>      __dev_t st_rdev;
> -#if !defined __USE_FILE_OFFSET64
> +# if !defined __USE_FILE_OFFSET64
>      unsigned int st_pad2[2];	/* Reserved for st_rdev expansion  */
>      __off_t st_size;
>      int st_pad3;
> -#else
> +# else
>      unsigned int st_pad2[3];	/* Reserved for st_rdev expansion  */
>      __off64_t st_size;
> -#endif
> -#ifdef __USE_XOPEN2K8
> +# endif
> +# ifdef __USE_XOPEN2K8
>      /* Nanosecond resolution timestamps are stored in a format
>         equivalent to 'struct timespec'.  This is the type used
>         whenever possible but the Unix namespace rules do not allow the
> @@ -151,24 +161,24 @@ struct stat
>      struct timespec st_atim;            /* Time of last access.  */
>      struct timespec st_mtim;            /* Time of last modification.  */
>      struct timespec st_ctim;            /* Time of last status change.  */
> -# define st_atime st_atim.tv_sec        /* Backward compatibility.  */
> -# define st_mtime st_mtim.tv_sec
> -# define st_ctime st_ctim.tv_sec
> -#else
> +#  define st_atime st_atim.tv_sec        /* Backward compatibility.  */
> +#  define st_mtime st_mtim.tv_sec
> +#  define st_ctime st_ctim.tv_sec
> +# else
>      __time_t st_atime;			/* Time of last access.  */
>      unsigned long int st_atimensec;	/* Nscecs of last access.  */
>      __time_t st_mtime;			/* Time of last modification.  */
>      unsigned long int st_mtimensec;	/* Nsecs of last modification.  */
>      __time_t st_ctime;			/* Time of last status change.  */
>      unsigned long int st_ctimensec;	/* Nsecs of last status change.  */
> -#endif
> +# endif
>      __blksize_t st_blksize;
>      unsigned int st_pad4;
> -#ifndef __USE_FILE_OFFSET64
> +# ifndef __USE_FILE_OFFSET64
>      __blkcnt_t st_blocks;
> -#else
> +# else
>      __blkcnt64_t st_blocks;
> -#endif
> +# endif
>      int st_pad5[14];
>    };
>  
> @@ -185,7 +195,7 @@ struct stat64
>      __dev_t st_rdev;
>      unsigned int st_pad2[3];	/* Reserved for st_rdev expansion  */
>      __off64_t st_size;
> -# ifdef __USE_XOPEN2K8
> +#  ifdef __USE_XOPEN2K8
>      /* Nanosecond resolution timestamps are stored in a format
>         equivalent to 'struct timespec'.  This is the type used
>         whenever possible but the Unix namespace rules do not allow the
> @@ -195,20 +205,21 @@ struct stat64
>      struct timespec st_atim;            /* Time of last access.  */
>      struct timespec st_mtim;            /* Time of last modification.  */
>      struct timespec st_ctim;            /* Time of last status change.  */
> -# else
> +#  else
>      __time_t st_atime;			/* Time of last access.  */
>      unsigned long int st_atimensec;	/* Nscecs of last access.  */
>      __time_t st_mtime;			/* Time of last modification.  */
>      unsigned long int st_mtimensec;	/* Nsecs of last modification.  */
>      __time_t st_ctime;			/* Time of last status change.  */
>      unsigned long int st_ctimensec;	/* Nsecs of last status change.  */
> -# endif
> +#  endif
>      __blksize_t st_blksize;
>      unsigned int st_pad3;
>      __blkcnt64_t st_blocks;
>      int st_pad4[14];
>  };
>  #endif
> +
>  #endif
>  
>  /* Tell code we have these members.  */
> diff --git a/sysdeps/unix/sysv/linux/powerpc/bits/struct_stat.h b/sysdeps/unix/sysv/linux/powerpc/bits/struct_stat.h
> index 12caab2790..f55eb658a2 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/bits/struct_stat.h
> +++ b/sysdeps/unix/sysv/linux/powerpc/bits/struct_stat.h
> @@ -26,35 +26,37 @@
>  #include <bits/wordsize.h>
>  
>  #if __WORDSIZE == 32
> -
>  struct stat
>    {
> +# ifdef __USE_TIME_BITS64
> +#  include <bits/struct_stat_time64_helper.h>

OK. Use helper.

> +# else
>      __dev_t st_dev;			/* Device.  */
> -# ifndef __USE_FILE_OFFSET64
> +#  ifndef __USE_FILE_OFFSET64
>      unsigned short int __pad1;
>      __ino_t st_ino;			/* File serial number.	*/
> -# else
> +#  else
>      __ino64_t st_ino;			/* File serial number.	*/
> -# endif
> +#  endif
>      __mode_t st_mode;			/* File mode.  */
>      __nlink_t st_nlink;			/* Link count.  */
>      __uid_t st_uid;			/* User ID of the file's owner.	*/
>      __gid_t st_gid;			/* Group ID of the file's group.*/
>      __dev_t st_rdev;			/* Device number, if device.  */
>      unsigned short int __pad2;
> -# ifndef __USE_FILE_OFFSET64
> +#  ifndef __USE_FILE_OFFSET64
>      __off_t st_size;			/* Size of file, in bytes.  */
> -# else
> +#  else
>      __off64_t st_size;			/* Size of file, in bytes.  */
> -# endif
> +#  endif
>      __blksize_t st_blksize;		/* Optimal block size for I/O.  */
>  
> -# ifndef __USE_FILE_OFFSET64
> +#  ifndef __USE_FILE_OFFSET64
>      __blkcnt_t st_blocks;		/* Number 512-byte blocks allocated. */
> -# else
> +#  else
>      __blkcnt64_t st_blocks;		/* Number 512-byte blocks allocated. */
> -# endif
> -# ifdef __USE_XOPEN2K8
> +#  endif
> +#  ifdef __USE_XOPEN2K8
>      /* Nanosecond resolution timestamps are stored in a format
>         equivalent to 'struct timespec'.  This is the type used
>         whenever possible but the Unix namespace rules do not allow the
> @@ -64,25 +66,28 @@ struct stat
>      struct timespec st_atim;		/* Time of last access.  */
>      struct timespec st_mtim;		/* Time of last modification.  */
>      struct timespec st_ctim;		/* Time of last status change.  */
> -#  define st_atime st_atim.tv_sec	/* Backward compatibility.  */
> -#  define st_mtime st_mtim.tv_sec
> -#  define st_ctime st_ctim.tv_sec
> -# else
> +#   define st_atime st_atim.tv_sec	/* Backward compatibility.  */
> +#   define st_mtime st_mtim.tv_sec
> +#   define st_ctime st_ctim.tv_sec
> +#  else
>      __time_t st_atime;			/* Time of last access.  */
>      unsigned long int st_atimensec;	/* Nscecs of last access.  */
>      __time_t st_mtime;			/* Time of last modification.  */
>      unsigned long int st_mtimensec;	/* Nsecs of last modification.  */
>      __time_t st_ctime;			/* Time of last status change.  */
>      unsigned long int st_ctimensec;	/* Nsecs of last status change.  */
> -# endif
> +#  endif
>      unsigned long int __glibc_reserved4;
>      unsigned long int __glibc_reserved5;
> +# endif /* __USE_TIME_BITS64 */
>    };
>  
> -
>  # ifdef __USE_LARGEFILE64
>  struct stat64
>    {
> +#  ifdef __USE_TIME_BITS64
> +#   include <bits/struct_stat_time64_helper.h>

OK. Use helper.

> +#  else
>      __dev_t st_dev;			/* Device.  */
>      __ino64_t st_ino;			/* File serial number.	*/
>      __mode_t st_mode;			/* File mode.  */
> @@ -94,7 +99,7 @@ struct stat64
>      __off64_t st_size;			/* Size of file, in bytes.  */
>      __blksize_t st_blksize;		/* Optimal block size for I/O.  */
>      __blkcnt64_t st_blocks;		/* Number 512-byte blocks allocated. */
> -#  ifdef __USE_XOPEN2K8
> +#   ifdef __USE_XOPEN2K8
>      /* Nanosecond resolution timestamps are stored in a format
>         equivalent to 'struct timespec'.  This is the type used
>         whenever possible but the Unix namespace rules do not allow the
> @@ -104,19 +109,20 @@ struct stat64
>      struct timespec st_atim;		/* Time of last access.  */
>      struct timespec st_mtim;		/* Time of last modification.  */
>      struct timespec st_ctim;		/* Time of last status change.  */
> -#   define st_atime st_atim.tv_sec	/* Backward compatibility.  */
> -#   define st_mtime st_mtim.tv_sec
> -#   define st_ctime st_ctim.tv_sec
> -#  else
> +#    define st_atime st_atim.tv_sec	/* Backward compatibility.  */
> +#    define st_mtime st_mtim.tv_sec
> +#    define st_ctime st_ctim.tv_sec
> +#   else
>      __time_t st_atime;			/* Time of last access.  */
>      unsigned long int st_atimensec;	/* Nscecs of last access.  */
>      __time_t st_mtime;			/* Time of last modification.  */
>      unsigned long int st_mtimensec;	/* Nsecs of last modification.  */
>      __time_t st_ctime;			/* Time of last status change.  */
>      unsigned long int st_ctimensec;	/* Nsecs of last status change.  */
> -#  endif
> +#   endif
>      unsigned long int __glibc_reserved4;
>      unsigned long int __glibc_reserved5;
> +#  endif /* __USE_TIME_BITS64 */
>    };
>  # endif /* __USE_LARGEFILE64 */
>  
> diff --git a/sysdeps/unix/sysv/linux/s390/bits/struct_stat.h b/sysdeps/unix/sysv/linux/s390/bits/struct_stat.h
> index a733622cf5..f2933b8b12 100644
> --- a/sysdeps/unix/sysv/linux/s390/bits/struct_stat.h
> +++ b/sysdeps/unix/sysv/linux/s390/bits/struct_stat.h
> @@ -65,32 +65,35 @@ struct stat
>  #else
>  struct stat
>    {
> +# ifdef __USE_TIME_BITS64
> +#  include <bits/struct_stat_time64_helper.h>

OK. Use helper.

> +# else
>      __dev_t st_dev;			/* Device.  */
>      unsigned int __pad1;
> -# ifndef __USE_FILE_OFFSET64
> +#  ifndef __USE_FILE_OFFSET64
>      __ino_t st_ino;			/* File serial number.	*/
> -# else
> +#  else
>      __ino_t __st_ino;			/* 32bit file serial number.	*/
> -# endif
> +#  endif
>      __mode_t st_mode;			/* File mode.  */
>      __nlink_t st_nlink;			/* Link count.  */
>      __uid_t st_uid;			/* User ID of the file's owner.	*/
>      __gid_t st_gid;			/* Group ID of the file's group.*/
>      __dev_t st_rdev;			/* Device number, if device.  */
>      unsigned int __pad2;
> -# ifndef __USE_FILE_OFFSET64
> +#  ifndef __USE_FILE_OFFSET64
>      __off_t st_size;			/* Size of file, in bytes.  */
> -# else
> +#  else
>      __off64_t st_size;			/* Size of file, in bytes.  */
> -# endif
> +#  endif
>      __blksize_t st_blksize;		/* Optimal block size for I/O.  */
>  
> -# ifndef __USE_FILE_OFFSET64
> +#  ifndef __USE_FILE_OFFSET64
>      __blkcnt_t st_blocks;		/* Number 512-byte blocks allocated. */
> -# else
> +#  else
>      __blkcnt64_t st_blocks;		/* Number 512-byte blocks allocated. */
> -# endif
> -# ifdef __USE_XOPEN2K8
> +#  endif
> +#  ifdef __USE_XOPEN2K8
>      /* Nanosecond resolution timestamps are stored in a format
>         equivalent to 'struct timespec'.  This is the type used
>         whenever possible but the Unix namespace rules do not allow the
> @@ -100,25 +103,26 @@ struct stat
>      struct timespec st_atim;		/* Time of last access.  */
>      struct timespec st_mtim;		/* Time of last modification.  */
>      struct timespec st_ctim;		/* Time of last status change.  */
> -#  define st_atime st_atim.tv_sec	/* Backward compatibility.  */
> -#  define st_mtime st_mtim.tv_sec
> -#  define st_ctime st_ctim.tv_sec
> -# else
> +#   define st_atime st_atim.tv_sec	/* Backward compatibility.  */
> +#   define st_mtime st_mtim.tv_sec
> +#   define st_ctime st_ctim.tv_sec
> +#  else
>      __time_t st_atime;			/* Time of last access.  */
>      unsigned long int st_atimensec;	/* Nscecs of last access.  */
>      __time_t st_mtime;			/* Time of last modification.  */
>      unsigned long int st_mtimensec;	/* Nsecs of last modification.  */
>      __time_t st_ctime;			/* Time of last status change.  */
>      unsigned long int st_ctimensec;	/* Nsecs of last status change.  */
> -# endif
> -# ifndef __USE_FILE_OFFSET64
> +#  endif
> +#  ifndef __USE_FILE_OFFSET64
>      unsigned long int __glibc_reserved4;
>      unsigned long int __glibc_reserved5;
> -# else
> +#  else
>      __ino64_t st_ino;			/* File serial number.	*/
> +#  endif
>  # endif
>    };
> -#endif
> +# endif
>  
>  #ifdef __USE_LARGEFILE64
>  # if __WORDSIZE == 64
> @@ -162,6 +166,9 @@ struct stat64
>  # else
>  struct stat64
>    {
> +#  ifdef __USE_TIME_BITS64
> +#   include <bits/struct_stat_time64_helper.h>

OK. Use helper.

> +#  else
>      __dev_t st_dev;			/* Device.  */
>      unsigned int __pad1;
>  
> @@ -176,7 +183,7 @@ struct stat64
>      __blksize_t st_blksize;		/* Optimal block size for I/O.  */
>  
>      __blkcnt64_t st_blocks;		/* Number 512-byte blocks allocated. */
> -#  ifdef __USE_XOPEN2K8
> +#   ifdef __USE_XOPEN2K8
>      /* Nanosecond resolution timestamps are stored in a format
>         equivalent to 'struct timespec'.  This is the type used
>         whenever possible but the Unix namespace rules do not allow the
> @@ -186,18 +193,19 @@ struct stat64
>      struct timespec st_atim;		/* Time of last access.  */
>      struct timespec st_mtim;		/* Time of last modification.  */
>      struct timespec st_ctim;		/* Time of last status change.  */
> -#   define st_atime st_atim.tv_sec	/* Backward compatibility.  */
> -#   define st_mtime st_mtim.tv_sec
> -#   define st_ctime st_ctim.tv_sec
> -#  else
> +#    define st_atime st_atim.tv_sec	/* Backward compatibility.  */
> +#    define st_mtime st_mtim.tv_sec
> +#    define st_ctime st_ctim.tv_sec
> +#   else
>      __time_t st_atime;			/* Time of last access.  */
>      unsigned long int st_atimensec;	/* Nscecs of last access.  */
>      __time_t st_mtime;			/* Time of last modification.  */
>      unsigned long int st_mtimensec;	/* Nsecs of last modification.  */
>      __time_t st_ctime;			/* Time of last status change.  */
>      unsigned long int st_ctimensec;	/* Nsecs of last status change.  */
> -#  endif
> +#   endif
>      __ino64_t st_ino;			/* File serial number.		*/
> +#  endif
>    };
>  # endif
>  #endif
> diff --git a/sysdeps/unix/sysv/linux/struct_stat_time64.h b/sysdeps/unix/sysv/linux/struct_stat_time64.h
> index f0a29d7fe5..260d1812be 100644
> --- a/sysdeps/unix/sysv/linux/struct_stat_time64.h
> +++ b/sysdeps/unix/sysv/linux/struct_stat_time64.h
> @@ -22,64 +22,13 @@
>  #if __TIMESIZE == 64
>  # define __stat64_t64 stat64
>  #else

OK. We should be removing much of this file because it was refactored into the helper.

> -# ifdef __USE_LARGEFILE64
> -#  include <endian.h>
> -
> -/* The definition should be equal to the 'struct __timespec64' internal
> -   layout.  */
> -#  if BYTE_ORDER == BIG_ENDIAN
> -#   define __fieldts64(name) 					\
> -     __time64_t name; __int32_t :32; __int32_t name ## nsec
> -#  else
> -#   define __fieldts64(name)					\
> -     __time64_t name; __int32_t name ## nsec; __int32_t :32
> -#  endif
> -
> -/* Workaround for the definition from struct_stat.h  */
> -#  undef st_atime
> -#  undef st_mtime
> -#  undef st_ctime
> +# include <struct___timespec64.h>
>  
>  struct __stat64_t64
>    {
> -    __dev_t st_dev;			/* Device.  */
> -    __ino64_t st_ino;			/* file serial number.	*/
> -    __mode_t st_mode;			/* File mode.  */
> -    __nlink_t st_nlink;			/* Link count.  */
> -    __uid_t st_uid;			/* User ID of the file's owner.	*/
> -    __gid_t st_gid;			/* Group ID of the file's group.*/
> -    __dev_t st_rdev;			/* Device number, if device.  */
> -    __off64_t st_size;			/* Size of file, in bytes.  */
> -    __blksize_t st_blksize;		/* Optimal block size for I/O.  */
> -    __blkcnt64_t st_blocks;		/* Number 512-byte blocks allocated. */
> -#   ifdef __USE_XOPEN2K8
> -    /* Nanosecond resolution timestamps are stored in a format
> -       equivalent to 'struct timespec'.  This is the type used
> -       whenever possible but the Unix namespace rules do not allow the
> -       identifier 'timespec' to appear in the <sys/stat.h> header.
> -       Therefore we have to handle the use of this header in strictly
> -       standard-compliant sources special.  */
> -    struct __timespec64 st_atim;	/* Time of last access.  */
> -    struct __timespec64 st_mtim;	/* Time of last modification.  */
> -    struct __timespec64 st_ctim;	/* Time of last status change.  */
> -#    define st_atime st_atim.tv_sec	/* Backward compatibility.  */
> -#    define st_mtime st_mtim.tv_sec
> -#    define st_ctime st_ctim.tv_sec
> -#   else
> -    __fieldts64 (st_atime);
> -    __fieldts64 (st_mtime);
> -    __fieldts64 (st_ctime);
> -#   endif /* __USE_XOPEN2K8  */
> +# define __struct_timespec struct __timespec64
> +# include <bits/struct_stat_time64_helper.h>

OK. As expected, refactored away.

>    };
> -
> -#   define _STATBUF_ST_BLKSIZE
> -#   define _STATBUF_ST_RDEV
> -#   define _STATBUF_ST_NSEC
> -
> -#   undef __fieldts64
> -
> -#  endif /* __USE_LARGEFILE64  */
> -
> -# endif /* __TIMESIZE == 64  */
> +#endif /* __TIMESIZE == 64  */
>  
>  #endif /* _BITS_STRUCT_STAT_TIME64_H  */
> diff --git a/sysdeps/unix/sysv/linux/x86/bits/struct_stat.h b/sysdeps/unix/sysv/linux/x86/bits/struct_stat.h
> index 6ddd01db46..01ee7ff6b3 100644
> --- a/sysdeps/unix/sysv/linux/x86/bits/struct_stat.h
> +++ b/sysdeps/unix/sysv/linux/x86/bits/struct_stat.h
> @@ -25,43 +25,46 @@
>  
>  struct stat
>    {
> +#ifdef __USE_TIME_BITS64
> +# include <bits/struct_stat_time64_helper.h>

OK. Use helper.

> +#else
>      __dev_t st_dev;		/* Device.  */
> -#ifndef __x86_64__
> +# ifndef __x86_64__
>      unsigned short int __pad1;
> -#endif
> -#if defined __x86_64__ || !defined __USE_FILE_OFFSET64
> +# endif
> +# if defined __x86_64__ || !defined __USE_FILE_OFFSET64
>      __ino_t st_ino;		/* File serial number.	*/
> -#else
> +# else
>      __ino_t __st_ino;			/* 32bit file serial number.	*/
> -#endif
> -#ifndef __x86_64__
> +# endif
> +# ifndef __x86_64__
>      __mode_t st_mode;			/* File mode.  */
>      __nlink_t st_nlink;			/* Link count.  */
> -#else
> +# else
>      __nlink_t st_nlink;		/* Link count.  */
>      __mode_t st_mode;		/* File mode.  */
> -#endif
> +# endif
>      __uid_t st_uid;		/* User ID of the file's owner.	*/
>      __gid_t st_gid;		/* Group ID of the file's group.*/
> -#ifdef __x86_64__
> +# ifdef __x86_64__
>      int __pad0;
> -#endif
> +# endif
>      __dev_t st_rdev;		/* Device number, if device.  */
> -#ifndef __x86_64__
> +# ifndef __x86_64__
>      unsigned short int __pad2;
> -#endif
> -#if defined __x86_64__ || !defined __USE_FILE_OFFSET64
> +# endif
> +# if defined __x86_64__ || !defined __USE_FILE_OFFSET64
>      __off_t st_size;			/* Size of file, in bytes.  */
> -#else
> +# else
>      __off64_t st_size;			/* Size of file, in bytes.  */
> -#endif
> +# endif
>      __blksize_t st_blksize;	/* Optimal block size for I/O.  */
> -#if defined __x86_64__  || !defined __USE_FILE_OFFSET64
> +# if defined __x86_64__  || !defined __USE_FILE_OFFSET64
>      __blkcnt_t st_blocks;		/* Number 512-byte blocks allocated. */
> -#else
> +# else
>      __blkcnt64_t st_blocks;		/* Number 512-byte blocks allocated. */
> -#endif
> -#ifdef __USE_XOPEN2K8
> +# endif
> +# ifdef __USE_XOPEN2K8
>      /* Nanosecond resolution timestamps are stored in a format
>         equivalent to 'struct timespec'.  This is the type used
>         whenever possible but the Unix namespace rules do not allow the
> @@ -71,58 +74,62 @@ struct stat
>      struct timespec st_atim;		/* Time of last access.  */
>      struct timespec st_mtim;		/* Time of last modification.  */
>      struct timespec st_ctim;		/* Time of last status change.  */
> -# define st_atime st_atim.tv_sec	/* Backward compatibility.  */
> -# define st_mtime st_mtim.tv_sec
> -# define st_ctime st_ctim.tv_sec
> -#else
> +#  define st_atime st_atim.tv_sec	/* Backward compatibility.  */
> +#  define st_mtime st_mtim.tv_sec
> +#  define st_ctime st_ctim.tv_sec
> +# else
>      __time_t st_atime;			/* Time of last access.  */
>      __syscall_ulong_t st_atimensec;	/* Nscecs of last access.  */
>      __time_t st_mtime;			/* Time of last modification.  */
>      __syscall_ulong_t st_mtimensec;	/* Nsecs of last modification.  */
>      __time_t st_ctime;			/* Time of last status change.  */
>      __syscall_ulong_t st_ctimensec;	/* Nsecs of last status change.  */
> -#endif
> -#ifdef __x86_64__
> +# endif
> +# ifdef __x86_64__
>      __syscall_slong_t __glibc_reserved[3];
> -#else
> -# ifndef __USE_FILE_OFFSET64
> +# else
> +#  ifndef __USE_FILE_OFFSET64
>      unsigned long int __glibc_reserved4;
>      unsigned long int __glibc_reserved5;
> -# else
> +#  else
>      __ino64_t st_ino;			/* File serial number.	*/
> +#  endif
>  # endif
> -#endif
> +#endif /* __USE_TIME_BITS64  */
>    };
>  
>  #ifdef __USE_LARGEFILE64
>  /* Note stat64 has the same shape as stat for x86-64.  */
>  struct stat64
>    {
> +# ifdef __USE_TIME_BITS64
> +#  include <bits/struct_stat_time64_helper.h>

OK. Use helper.

> +# else
>      __dev_t st_dev;		/* Device.  */
> -# ifdef __x86_64__
> +#  ifdef __x86_64__
>      __ino64_t st_ino;		/* File serial number.  */
>      __nlink_t st_nlink;		/* Link count.  */
>      __mode_t st_mode;		/* File mode.  */
> -# else
> +#  else
>      unsigned int __pad1;
>      __ino_t __st_ino;			/* 32bit file serial number.	*/
>      __mode_t st_mode;			/* File mode.  */
>      __nlink_t st_nlink;			/* Link count.  */
> -# endif
> +#  endif
>      __uid_t st_uid;		/* User ID of the file's owner.	*/
>      __gid_t st_gid;		/* Group ID of the file's group.*/
> -# ifdef __x86_64__
> +#  ifdef __x86_64__
>      int __pad0;
>      __dev_t st_rdev;		/* Device number, if device.  */
>      __off_t st_size;		/* Size of file, in bytes.  */
> -# else
> +#  else
>      __dev_t st_rdev;			/* Device number, if device.  */
>      unsigned int __pad2;
>      __off64_t st_size;			/* Size of file, in bytes.  */
> -# endif
> +#  endif
>      __blksize_t st_blksize;	/* Optimal block size for I/O.  */
>      __blkcnt64_t st_blocks;	/* Nr. 512-byte blocks allocated.  */
> -# ifdef __USE_XOPEN2K8
> +#  ifdef __USE_XOPEN2K8
>      /* Nanosecond resolution timestamps are stored in a format
>         equivalent to 'struct timespec'.  This is the type used
>         whenever possible but the Unix namespace rules do not allow the
> @@ -132,19 +139,20 @@ struct stat64
>      struct timespec st_atim;		/* Time of last access.  */
>      struct timespec st_mtim;		/* Time of last modification.  */
>      struct timespec st_ctim;		/* Time of last status change.  */
> -# else
> +#  else
>      __time_t st_atime;			/* Time of last access.  */
>      __syscall_ulong_t st_atimensec;	/* Nscecs of last access.  */
>      __time_t st_mtime;			/* Time of last modification.  */
>      __syscall_ulong_t st_mtimensec;	/* Nsecs of last modification.  */
>      __time_t st_ctime;			/* Time of last status change.  */
>      __syscall_ulong_t st_ctimensec;	/* Nsecs of last status change.  */
> -# endif
> -# ifdef __x86_64__
> +#  endif
> +#  ifdef __x86_64__
>      __syscall_slong_t __glibc_reserved[3];
> -# else
> +#  else
>      __ino64_t st_ino;			/* File serial number.		*/
> -# endif
> +#  endif
> +# endif /* __USE_TIME_BITS64  */
>    };
>  #endif
>  
>

On 04/06/2021 16:37, Carlos O'Donell wrote:
> On 5/18/21 4:56 PM, Adhemerval Zanella wrote:
>> From: Lukasz Majewski <lukma@denx.de>
>>
>> Instead of replicate the same definitions from struct_stat_time64.h
>> on the multiple struct_stat.h, use a common header which is included
>> when required (struct_stat_time64_helper.h).  The 64-bit time support
>> is added only for LFS support.
>>
>> The __USE_TIME_BITS64 is not defined internally yet, although the
>> internal header is used when building the 64-bit stat implementations.
> 
> Requesting a v3 please.
> 
> Please add the __glibc_reserved* members to the structures to preserve
> maximum compatibility with the kernel structure.
> 
> See review of patch 14/25 for more general details.
> 
> I am almost OK with this change as-is because in general everyone
> should be using statx at this point with the ability to extend and
> provide more information.
> 
> However because the kernel contains:
> 
>  24 struct stat {

This struct more specifically is the one used on compat non-LFS syscalls,
which glibc only issues for compat symbols. But even the 'struct stat64'
does add the two extra unused members.

>  25         unsigned long   st_dev;         /* Device.  */
>  26         unsigned long   st_ino;         /* File serial number.  */
>  27         unsigned int    st_mode;        /* File mode.  */
>  28         unsigned int    st_nlink;       /* Link count.  */
>  29         unsigned int    st_uid;         /* User ID of the file's owner.  */
>  30         unsigned int    st_gid;         /* Group ID of the file's group. */
>  31         unsigned long   st_rdev;        /* Device number, if device.  */
>  32         unsigned long   __pad1;
>  33         long            st_size;        /* Size of file, in bytes.  */
>  34         int             st_blksize;     /* Optimal block size for I/O.  */
>  35         int             __pad2;
>  36         long            st_blocks;      /* Number 512-byte blocks allocated. */
>  37         long            st_atime;       /* Time of last access.  */
>  38         unsigned long   st_atime_nsec;
>  39         long            st_mtime;       /* Time of last modification.  */
>  40         unsigned long   st_mtime_nsec;
>  41         long            st_ctime;       /* Time of last status change.  */
>  42         unsigned long   st_ctime_nsec;
>  43         unsigned int    __unused4;
>  44         unsigned int    __unused5;
>  45 };
> 
> With __unused4 and __unused5. I think we should match this ABI as closely as we can
> to avoid future compatibility issues with legacy APIs.
> 

These kernel interfaces are really a mess and not really in sync across
architectures. Some ABI adds the reserved fields only for non LFS,
which the generic interface adds regardless.  And from kernel comment
the reversed fields were added to allow glibc compatibility, not
really to provide further extension.

In any case , I think it should not hurt to add two extra unsigned int 
reserved fields for 64 bit time support.


> OK. Reindent.
> 
>>    };
>>  #endif
>>  
>> @@ -127,5 +135,4 @@ struct stat64
>>  /* Nanosecond resolution time values are supported.  */
>>  #define _STATBUF_ST_NSEC
>>  
>> -
> 
> Please avoid spurious empty line removal when not related to the patch at hand.

Ack.

> 
>> +  __blksize_t st_blksize;	/* Optimal block size for I/O.  */
>> +  __blkcnt64_t st_blocks;	/* Number 512-byte blocks allocated. */
> 
> OK.
> 
> Plase add __glibc_reserved4 and __glibc_reserved5 here.

Ack.