source: branches/libc-0.6/src/libctests/glibc/elf/tst-tls6.c

#include <dlfcn.h>
#include <stdio.h>
#include <stdlib.h>

#include <link.h>
#include <tls.h>


#define TEST_FUNCTION do_test ()
static int
do_test (void)
{
#ifdef USE_TLS
  static const char modname[] = "tst-tlsmod2.so";
  int result = 0;
  int *foop;
  int *foop2;
  int (*fp) (int, int *);
  void *h;
  int i;
  int modid = -1;

  for (i = 0; i < 10; ++i)
    {
      h = dlopen (modname, RTLD_LAZY);
      if (h == NULL)
        {
          printf ("cannot open '%s': %s\n", modname, dlerror ());
          exit (1);
        }

      /* Dirty test code here: we peek into a private data structure.
         We make sure that the module gets assigned the same ID every
         time.  The value of the first round is used.  */
      if (modid == -1)
        modid = ((struct link_map *) h)->l_tls_modid;
      else if (((struct link_map *) h)->l_tls_modid != modid)
        {
          printf ("round %d: modid now %zd, initially %d\n",
                  i, ((struct link_map *) h)->l_tls_modid, modid);
          result = 1;
        }

      foop = dlsym (h, "foo");
      if (foop == NULL)
        {
          printf ("cannot get symbol 'foo': %s\n", dlerror ());
          exit (1);
        }

      *foop = 42 + i;

      fp = dlsym (h, "in_dso");
      if (fp == NULL)
        {
          printf ("cannot get symbol 'in_dso': %s\n", dlerror ());
          exit (1);
        }

      result |= fp (42 + i, foop);

      foop2 = dlsym (h, "foo");
      if (foop2 == NULL)
        {
          printf ("cannot get symbol 'foo' the second time: %s\n", dlerror ());
          exit (1);
        }

      if (foop != foop2)
        {
          puts ("address of 'foo' different the second time");
          result = 1;
        }
      else if (*foop != 16)
        {
          puts ("foo != 16");
          result = 1;
        }

      dlclose (h);
    }

  return result;
#else
  return 0;
#endif
}


#include "../test-skeleton.c"