Re: [PATCH 26/29] [AARCH64] Add sigstack.h header for ILP32 reasons.

[Will Newton <will dot newton at linaro dot org>]

On 27 October 2014 07:59, Andrew Pinski <apinski@cavium.com> wrote:
> ILP32 uses the same structure layout for sigaltstack as
> LP64 so we need a special header file.
>
> * sysdeps/unix/sysv/linux/aarch64/bits/sigstack.h: New file.
> ---
>  sysdeps/unix/sysv/linux/aarch64/bits/sigstack.h |   71 +++++++++++++++++++++++
>  1 files changed, 71 insertions(+), 0 deletions(-)
>  create mode 100644 sysdeps/unix/sysv/linux/aarch64/bits/sigstack.h
>
> diff --git a/sysdeps/unix/sysv/linux/aarch64/bits/sigstack.h b/sysdeps/unix/sysv/linux/aarch64/bits/sigstack.h
> new file mode 100644
> index 0000000..2dd8f6b
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/aarch64/bits/sigstack.h
> @@ -0,0 +1,71 @@
> +/* sigstack, sigaltstack definitions.
> +   Copyright (C) 1998, 1999 Free Software Foundation, Inc.

Copyright needs updating.

> +   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
> +   <http://www.gnu.org/licenses/>.  */
> +
> +#ifndef _SIGNAL_H
> +# error "Never include this file directly.  Use <signal.h> instead"
> +#endif
> +
> +
> +/* Structure describing a signal stack (obsolete).  */
> +struct sigstack
> +  {
> +    void *ss_sp;               /* Signal stack pointer.  */
> +    int ss_onstack;            /* Nonzero if executing on this stack.  */
> +  };
> +
> +
> +/* Possible values for `ss_flags.'.  */
> +enum
> +{
> +  SS_ONSTACK = 1,
> +#define SS_ONSTACK     SS_ONSTACK
> +  SS_DISABLE
> +#define SS_DISABLE     SS_DISABLE
> +};
> +
> +/* Minimum stack size for a signal handler.  */
> +#define MINSIGSTKSZ    2048
> +
> +/* System default stack size.  */
> +#define SIGSTKSZ       8192
> +
> +
> +/* Alternate, preferred interface.
> +   This structure matches the same size and layout
> +   for both ILP32 and LP64.  */
> +typedef struct sigaltstack
> +  {
> +#if defined(__ILP32__) && defined(__AARCH64EB__)
> +    int __pad_ss_sp;
> +#endif
> +    void *ss_sp;
> +#if defined(__ILP32__) && !defined(__AARCH64EB__)
> +    int __pad_ss_sp;
> +#endif
> +    int ss_flags;
> +#if defined(__ILP32__)
> +    int __pad_after_ss_flags;
> +#endif
> +#if defined(__ILP32__) && defined(__AARCH64EB__)
> +    int __pad_ss_size;
> +#endif
> +    size_t ss_size;
> +#if defined(__ILP32__) && !defined(__AARCH64EB__)
> +    int __pad_ss_size;
> +#endif
> +  } stack_t;


It might be simpler to have two definitions, one for __ILP32__ and one
for !__ILP32__ to tidy up the #ifdefs.

-- 
Will Newton
Toolchain Working Group, Linaro