Re: [Patch] arch recognition fix for osabi.c

[Daniel Jacobowitz <drow@mvista.com>]

On Tue, Jun 17, 2003 at 11:40:37AM -0400, Kris Warkentin wrote:
> Here are some changes to osabi.c that allow gdb to recognize QNX binaries
> properly.  The arch check change in gdbarch_init_osabi() allows the backend
> abi_init handlers to run.  I believe the comment still stand - we will
> probably want to do something smarter in the future.
> 
> The sniff change is only temporary.  It works reasonably well for now and
> will probably stay for backwards compatability but we are also going to add
> a special .note section like others OSes in the future.  Then we can check
> for both.
> 
> cheers,
> 
> Kris
> 
> Changelog:
>     * osabi.c (gdbarch_init_osabi): Just check arch for compatability rather
> identicality.

Your mailer is eating indentation again...

This half I'm not convinced by.  From our previous exchange I don't
think you've fully justified it.  Not approved without more discussion.

>       (generic_elf_osabi_sniff_abi_tag_sections): Add check for QNX Neutrino
> binaries.

This bit looks fine, except for two things: you've missed the coding
standards by four space characters (before left parens), and your
"safety first" check overruns the buffer (missing +1 in the alloca).

> Index: osabi.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/osabi.c,v
> retrieving revision 1.15
> diff -u -r1.15 osabi.c
> --- osabi.c 8 Jun 2003 18:27:14 -0000 1.15
> +++ osabi.c 17 Jun 2003 15:32:53 -0000
> @@ -311,8 +311,7 @@
>    type that is compatible with the desired machine type.  Right
>    now we simply return the first match, which is fine for now.
>    However, we might want to do something smarter in the future.  */
> -      compatible = arch_info->compatible (arch_info, handler->arch_info);
> -      if (compatible == handler->arch_info)
> +      if(arch_info->compatible (arch_info, handler->arch_info))
>   {
>     (*handler->init_osabi) (info, gdbarch);
>     return;
> @@ -430,6 +429,17 @@
>        necessary yet.  */
>     *os_ident_ptr = GDB_OSABI_NETBSD_ELF;
>   }
> +      return;
> +    }
> +
> +  /* QNX Neutrino has ldqnx.so as its linker.  */
> +  if (strcmp (name, ".interp") == 0 && sectsize > 0)
> +    {
> +      char *buf = alloca(sectsize);
> +      bfd_get_section_contents(abfd, sect, buf, 0, sectsize);
> +      buf[sectsize] = '\0'; /* Safety first boys and girls.  */
> +      if(strstr(buf, "ldqnx.so"))
> +        *os_ident_ptr = GDB_OSABI_QNXNTO;
>        return;
>      }
>  }
> 
> 
> 

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer