Re: [PATCH v2 15/16] dlfcn: Eliminate GLIBC_PRIVATE dependency from tststatic2

[Adhemerval Zanella <adhemerval.zanella@linaro.org>]

On 31/05/2021 11:12, Florian Weimer via Libc-alpha wrote:
> The test appears to use _dlfcn_hook@@GLIBC_PRIVATE as a way to
> test dlvsym without having to know the appropriate symbol version.
> With <first-versions.h>, we can use a public symbol and the symbol
> version at which it was defined first.

Right, I think by including the <first-versions.h> there is no need 
to make it an internal test.

LGTM, thanks.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>


> ---
>  dlfcn/modstatic2.c | 10 +++++++++-
>  dlfcn/tststatic2.c | 10 +++++++++-
>  2 files changed, 18 insertions(+), 2 deletions(-)
> 
> diff --git a/dlfcn/modstatic2.c b/dlfcn/modstatic2.c
> index 9b5aae8b9f..02d561a7b0 100644
> --- a/dlfcn/modstatic2.c
> +++ b/dlfcn/modstatic2.c
> @@ -4,6 +4,7 @@
>  #include <stdlib.h>
>  #include <string.h>
>  #include <gnu/lib-names.h>
> +#include <first-versions.h>
>  
>  int test (FILE *out, int a);
>  
> @@ -117,11 +118,18 @@ test (FILE *out, int a)
>        exit (1);
>      }
>  
> -  if (dlvsym (handle2, "_dlfcn_hook", "GLIBC_PRIVATE") == NULL)
> +  /* _exit is very unlikely to receive a second symbol version.  */
> +  void *exit_ptr = dlvsym (handle2, "_exit", FIRST_VERSION_libc__exit_STRING);
> +  if (exit_ptr == NULL)
>      {
>        fprintf (out, "dlvsym: %s\n", dlerror ());
>        exit (1);
>      }
> +  if (exit_ptr != dlsym (handle2, "_exit"))
> +    {
> +      fprintf (out, "dlvsym for _exit does not match dlsym\n");
> +      exit (1);
> +    }
>  
>    void *(*dlsymfn) (void *, const char *);
>    dlsymfn = dlsym (handle2, "dlsym");

Ok.

> diff --git a/dlfcn/tststatic2.c b/dlfcn/tststatic2.c
> index f8cd5a964b..5d8a7831b2 100644
> --- a/dlfcn/tststatic2.c
> +++ b/dlfcn/tststatic2.c
> @@ -4,6 +4,7 @@
>  #include <stdlib.h>
>  #include <string.h>
>  #include <gnu/lib-names.h>
> +#include <first-versions.h>
>  
>  static int
>  do_test (void)
> @@ -115,11 +116,18 @@ do_test (void)
>        exit (1);
>      }
>  
> -  if (dlvsym (handle2, "_dlfcn_hook", "GLIBC_PRIVATE") == NULL)
> +  /* _exit is very unlikely to receive a second symbol version.  */
> +  void *exit_ptr = dlvsym (handle2, "_exit", FIRST_VERSION_libc__exit_STRING);
> +  if (exit_ptr == NULL)
>      {
>        printf ("dlvsym: %s\n", dlerror ());
>        exit (1);
>      }
> +  if (exit_ptr != dlsym (handle2, "_exit"))
> +    {
> +      printf ("dlvsym for _exit does not match dlsym\n");
> +      exit (1);
> +    }
>  
>    void *(*dlsymfn) (void *, const char *);
>    dlsymfn = dlsym (handle2, "dlsym");
> 

Ok.