Re: [hurd-amd64] ibus test failures

[Samuel Thibault]

Diego Nieto Cid, le mar. 31 déc. 2024 20:48:08 +0000, a ecrit:
> On Tue, Dec 31, 2024 at 08:32:47PM +0000, Diego Nieto Cid wrote:
> > 
> > Adding the following line to the program:
> > 
> >     printf("cmsghdr: %lu\n", sizeof (struct cmsghdr));
> > 
> > shows 12 on Hurd and 16 on Linux. I think I'm closer :)
> 
> The only difference in the structure definition is the cmsg_len field type
> which happens to be the 4 missing bytes.
> 
> --- >8 --- >8 ---
> Linux
> =====
> 
>     /* Structure used for storage of ancillary data object information.  */
>     struct cmsghdr
>      {
>         size_t cmsg_len;            /* Length of data in cmsg_data plus length
>                                        of cmsghdr structure.
>                                        !! The type should be socklen_t but the
>                                        definition of the kernel is 
> incompatible
>                                        with this.  */
>         int cmsg_level;             /* Originating protocol.  */
>         int cmsg_type;              /* Protocol specific type.  */
>     #if __glibc_c99_flexarr_available
>         __extension__ unsigned char __cmsg_data __flexarr; /* Ancillary data. 
>  */
>     #endif
>       };
> 
> Hurd
> ====
> 
>     /* Structure used for storage of ancillary data object information.  */
>     struct cmsghdr
>       {
>         socklen_t cmsg_len;         /* Length of data in cmsg_data plus length
>                                        of cmsghdr structure.  */

That's the correct type according to posix:

./basedefs/sys_socket.h.html:<tt>socklen_t  cmsg_len   </tt> Data byte count, 
including the <b>cmsghdr</b>. <tt>

>         int cmsg_level;             /* Originating protocol.  */
>         int cmsg_type;              /* Protocol specific type.  */
>     #if __glibc_c99_flexarr_available
>         __extension__ unsigned char __cmsg_data __flexarr; /* Ancillary data. 
>  */
>     #endif
>   };
> --- >8 --- >8 ---