Re: [PATCH 07/10] __frame_state_for: Use <unwind-link.h> for unwinder access

[Carlos O'Donell <carlos@redhat.com>]

On 2/17/21 11:03 AM, Florian Weimer via Libc-alpha wrote:

LGTM. Cleanup generic __frame_state_for.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>

> ---
>  sysdeps/generic/framestate.c | 21 ++++++++-------------
>  1 file changed, 8 insertions(+), 13 deletions(-)
> 
> diff --git a/sysdeps/generic/framestate.c b/sysdeps/generic/framestate.c
> index c1b364dbaa..54c4817f37 100644
> --- a/sysdeps/generic/framestate.c
> +++ b/sysdeps/generic/framestate.c
> @@ -17,7 +17,6 @@
>     License along with the GNU C Library; if not, see
>     <https://www.gnu.org/licenses/>.  */
>  
> -#include <dlfcn.h>
>  #include <stdlib.h>
>  #define STATIC static
>  #define __frame_state_for fallback_frame_state_for
> @@ -25,6 +24,8 @@
>  #undef __frame_state_for
>  #include <gnu/lib-names.h>
>  
> +#include <unwind-link.h>
> +
>  typedef struct frame_state * (*framesf)(void *pc, struct frame_state *);
>  struct frame_state *__frame_state_for (void *pc,
>  				       struct frame_state *frame_state);
> @@ -32,21 +33,15 @@ struct frame_state *__frame_state_for (void *pc,
>  struct frame_state *
>  __frame_state_for (void *pc, struct frame_state *frame_state)
>  {
> -  static framesf frame_state_for;
> -
> -  if (frame_state_for == NULL)
> +  struct unwind_link *unwind_link = __libc_unwind_link_get ();
> +  if (unwind_link != NULL)
> +    return UNWIND_LINK_PTR (unwind_link, __frame_state_for) (pc, frame_state);
> +  else
>      {
> -      void *handle = __libc_dlopen (LIBGCC_S_SO);
> -
> -      if (handle == NULL
> -	  || (frame_state_for
> -	      = (framesf) __libc_dlsym (handle, "__frame_state_for")) == NULL)
>  #ifndef __USING_SJLJ_EXCEPTIONS__
> -	frame_state_for = fallback_frame_state_for;
> +      return fallback_frame_state_for (pc, frame_state);
>  #else
> -	frame_state_for = abort;
> +      abort ();
>  #endif
>      }
> -
> -  return frame_state_for (pc, frame_state);
>  }
> 


-- 
Cheers,
Carlos.