Re: [PATCH] Make st_*tim visible in stat for POSIX.1-2008

[Yaakov Selkowitz <yselkowi at redhat dot com>]

On Wed, 2019-08-14 at 12:06 -0700, Dionna Amalie Glaze wrote:
> Ah you're right, I didn't properly handle the block size definitions.
> Here's another go at it that splits the timestamp declarations from the
> blocksize declarations.
> 
> ---
>  newlib/libc/include/sys/stat.h | 64 ++++++++++++++++++----------------
>  1 file changed, 34 insertions(+), 30 deletions(-)
> 
> diff --git a/newlib/libc/include/sys/stat.h b/newlib/libc/include/sys/stat.h
> index eee98db64..4a05081e4 100644
> --- a/newlib/libc/include/sys/stat.h
> +++ b/newlib/libc/include/sys/stat.h
> @@ -24,7 +24,7 @@ extern "C" {
>  #define stat64 stat
>  #endif
>  #else
> -struct stat
> +struct stat
>  {
>    dev_t                st_dev;
>    ino_t                st_ino;
> @@ -34,15 +34,11 @@ struct      stat
>    gid_t                st_gid;
>    dev_t                st_rdev;
>    off_t                st_size;
> -#if defined(__rtems__)
> +#if defined(__MISC_VISIBLE) || __POSIX_VISIBLE >= 200809 || defined(__rtems__)

The __*_VISIBLE macros are *always* defined, question is to what.   
These must therefore be used as #if __MISC_VISIBLE etc.

>    struct timespec st_atim;
>    struct timespec st_mtim;
>    struct timespec st_ctim;
> -  blksize_t     st_blksize;
> -  blkcnt_t     st_blocks;
> -#else
> -  /* SysV/sco doesn't have the rest... But Solaris, eabi does.  */
> -#if defined(__svr4__) && !defined(__PPC__) && !defined(__sun__)
> +#elif defined(__svr4__) && !defined(__PPC__) && !defined(__sun__)

What defined __srv4__ that should trigger this section?  It probably
needs to be moved before the #if __MISC_VISIBLE etc. hunk.

>    time_t       st_atime;
>    time_t       st_mtime;
>    time_t       st_ctime;
> @@ -53,14 +49,19 @@ struct      stat
>    long         st_spare2;
>    time_t       st_ctime;
>    long         st_spare3;
> +#endif
> +#if defined(__rtems__)
> +  blksize_t     st_blksize;
> +  blkcnt_t     st_blocks;
> +/* SysV/sco doesn't have the rest... But Solaris, eabi does.  */
> +#elif !defined(__svr4__) || defined(__PPC__) || defined(__sun__)
>    blksize_t    st_blksize;
>    blkcnt_t     st_blocks;
>    long st_spare4[2];
>  #endif
> -#endif
> };
> 
> -#if defined(__rtems__)
> +#if __POSIX_VISIBLE >= 200809 || defined(__rtems__)
> 
> On Wed, Aug 14, 2019 at 11:53 AM Yaakov Selkowitz wrote:
> > On Tue, 2019-08-13 at 11:29 -0700, Dionna Amalie Glaze via newlib
> > wrote:
> > > The st_{a,c,m}tim fields are needed for POSIX.1-2008, not just RTEMS.
> > > 
> > > Signed-off-by: Dionna Glaze <dionnaglaze@google.com>
> > > ---
> > >  newlib/libc/include/sys/stat.h | 6 ++++--
> > >  1 file changed, 4 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/newlib/libc/include/sys/stat.h
> > b/newlib/libc/include/sys/stat.h
> > > index eee98db64..052ef5a66 100644
> > > --- a/newlib/libc/include/sys/stat.h
> > > +++ b/newlib/libc/include/sys/stat.h
> > > @@ -34,10 +34,12 @@ struct      stat
> > >    gid_t                st_gid;
> > >    dev_t                st_rdev;
> > >    off_t                st_size;
> > > -#if defined(__rtems__)
> > > +#if defined(__USE_MISC) || __POSIX_VISIBLE >= 200809
> > 
> > Nak.
> > 
> > 1) __USE_MISC is a glibc internal and has no meaning within Newlib.
> > The proper guards must be used.
> > 
> > 2) This would cause the struct size to vary based on FTMs.  This is a
> > big no-no.  There needs to be size equivalent no-ops in an #else chunk
> > to match this.
> > 
> > >    struct timespec st_atim;
> > >    struct timespec st_mtim;
> > >    struct timespec st_ctim;
> > > +#endif
> > > +#if defined(__rtems__)
> > >    blksize_t     st_blksize;
> > >    blkcnt_t     st_blocks;
> > >  #else
> > > @@ -60,7 +62,7 @@ struct        stat
> > >  #endif
> > >  };
> > > 
> > > -#if defined(__rtems__)
> > > +#if __POSIX_VISIBLE >= 200809
> > >  #define st_atime st_atim.tv_sec
> > >  #define st_ctime st_ctim.tv_sec
> > >  #define st_mtime st_mtim.tv_sec

-- 
Yaakov Selkowitz
Senior Software Engineer - Platform Enablement
Red Hat, Inc.