Re: [PATCH] Separate siginfo_t for MIPS

[Rich Felker <dalias@libc.org>]

On Tue, Jan 26, 2016 at 11:24:54PM +0100, Szabolcs Nagy wrote:
> * Rich Felker <dalias@libc.org> [2015-12-15 23:34:28 -0500]:
> > On Thu, Dec 10, 2015 at 01:36:33PM +0100, Szabolcs Nagy wrote:
> > > * Dmitry Ivanov <dmitrijs.ivanovs@ubnt.com> [2015-12-10 12:47:12 +0200]:
> > > > MIPS has non-default siginfo_t structure. Also, some si_code values are
> > > > different. This patch is required for POSIX timers to work.
> ....
> > > until then i think it's enough to fix it in signal.h
> > > with some dirty ifdef around these members.
> > 
> > Indeed, I think a makeshift solution could work okay here and avoid
> > moving this large, redundant structure into bits/signal.h. However I'd
> > rather not depend on compiler-predefined macros (like __mips__ in
> > Dmitry's second patch) in public headers, since we don't assume
> > particular compilers for compiling applications.
> > 
> > Ideally bits/signal.h would define something in the reserved namespace
> > to change the behavior of the top-level signal.h. However
> > bits/signal.h needs to be towards the bottom of signal.h for other
> > reasons, so I don't see a really clean solution. Ideas?
> 
> workaround solution attached, only build tested

Why not just:

> diff --git a/arch/mips/bits/signal.h b/arch/mips/bits/signal.h
> index 818e0a7..50a0061 100644
> --- a/arch/mips/bits/signal.h
> +++ b/arch/mips/bits/signal.h
> @@ -73,6 +73,18 @@ typedef struct __ucontext {
>  #define SIG_UNBLOCK   2
>  #define SIG_SETMASK   3
>  
> +#undef SI_ASYNCIO
> +#undef SI_MESGQ
> +#undef SI_TIMER
> +#define SI_ASYNCIO (-2)
> +#define SI_MESGQ (-4)
> +#define SI_TIMER (-3)
> +
> +#undef si_errno
> +#undef si_code
> +#define si_errno __si_code
> +#define si_code  __si_errno

#define si_errno si_code
#define si_code  si_errno

> diff --git a/include/signal.h b/include/signal.h
> index 559362f..3496942 100644
> --- a/include/signal.h
> +++ b/include/signal.h
> @@ -86,7 +86,7 @@ union sigval {
>  };
>  
>  typedef struct {
> -	int si_signo, si_errno, si_code;
> +	int si_signo, __si_errno, __si_code;
>  	union {
>  		char __pad[128 - 2*sizeof(int) - sizeof(long)];
>  		struct {
> @@ -127,6 +127,8 @@ typedef struct {
>  		} __sigsys;
>  	} __si_fields;
>  } siginfo_t;
> +#define si_errno   __si_errno
> +#define si_code    __si_code

And omit this part entirely?

Rich