Re: Comments on mudflap

[Eyal Lebedinsky <eyal at eyal dot emu dot id dot au>]

Doug Graham wrote:
> Frank Eigler suggested that I send this to the list.  His comments
> follow mine.

[trimmed]

> One other minor thing.  On the Fedora Core 1 Linux system that I'm
> using for testing (with GLIBC 2.3.2), I get a mudflap violation every
> time I use one of the ctype routines (isdigit, isupper, islower, etc.)
> I assume that's because there is some array in the library that is
> accessed by the ctype macros, but which hasn't been registered with
> the mudflap runtime.  For the tests above, I've been using my own ctype
> replacement so as to avoid this problem.
>
> Regards,
> Doug.
>
> --------------------
>
> From: "Frank Ch. Eigler" <fche@redhat.com>
>
> Hi, Doug -

[trimmed]

> With respect to ctype, yes, these types of static arrays used by
> libc macros pose a problem.  One solution would require adding a few
> autoconf-sensitive lines to mf-runtime.c to register these during
> initialization much as environment variables and std* FILE objects are.
>
> - FChE

The abovementioned patch should be simple, just add the last three
__mf_register call statements to this function in
	gcc/libmudflap/mf-runtime.c.
Do include <ctype.h> somewhere at the top.

int
__wrap_main (int argc, char* argv[])
{
  extern char **environ;
  extern int main ();
  static int been_here = 0;

  if (__mf_opts.heur_std_data && ! been_here)
    {
      unsigned i;

      been_here = 1;
      __mf_register (argv, sizeof(char *)*(argc+1), __MF_TYPE_STATIC, "argv[]");
      for (i=0; i<argc; i++)
        {
          unsigned j = strlen (argv[i]);
          __mf_register (argv[i], j+1, __MF_TYPE_STATIC, "argv element");
        }

      for (i=0; ; i++)
        {
          char *e = environ[i];
          unsigned j;
          if (e == NULL) break;
          j = strlen (environ[i]);
          __mf_register (environ[i], j+1, __MF_TYPE_STATIC, "environ element");
        }
      __mf_register (environ, sizeof(char *)*(i+1), __MF_TYPE_STATIC, "environ[]");

      __mf_register (& errno, sizeof (errno), __MF_TYPE_STATIC, "errno area");

      __mf_register (stdin,  sizeof (*stdin),  __MF_TYPE_STATIC, "stdin");
      __mf_register (stdout, sizeof (*stdout), __MF_TYPE_STATIC, "stdout");
      __mf_register (stderr, sizeof (*stderr), __MF_TYPE_STATIC, "stderr");

      /* ctype.h tables */
      __mf_register (__ctype_b, sizeof (unsigned short int)*256,
                __MF_TYPE_STATIC, "__ctype_b");
      __mf_register (__ctype_tolower, sizeof (__int32_t)*256,
                __MF_TYPE_STATIC, "__ctype_tolower");
      __mf_register (__ctype_toupper, sizeof (__int32_t)*256,
                __MF_TYPE_STATIC, "__ctype_toupper");
    }

#ifdef PIC
  return main (argc, argv, environ);
#else
  return __real_main (argc, argv, environ);
#endif
}




--
--
Eyal Lebedinsky (eyal@eyal.emu.id.au) <http://samba.org/eyal/>