glibc/elf/noload.c

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

int
main (void)
{
  int result = 0;

  /* First try to load an object which is a dependency.  This should
     succeed.  */
  if (dlopen ("testobj1.so", RTLD_LAZY | RTLD_NOLOAD) == NULL)
    {
      printf ("cannot open \"testobj1.so\": %s\n", dlerror ());
      result = 1;
    }
  else
    puts ("loading \"testobj1.so\" succeeded, OK");

  /* Now try loading an object which is not already loaded.  */
  if (dlopen ("testobj5.so", RTLD_LAZY | RTLD_NOLOAD) != NULL)
    {
      puts ("succeeded in loading \"testobj5.so\"");
      result = 1;
    }
  else
    {
      /* Load the object and run the same test again.  */
      void *p;

      puts ("\"testobj5.so\" wasn't loaded and RTLD_NOLOAD prevented it, OK");

      p = dlopen ("testobj5.so", RTLD_LAZY);

      if (p == NULL)
	{
	  printf ("cannot open \"testobj5.so\" without RTLD_NOLOAD: %s\n",
		  dlerror ());
	  result = 1;
	}
      else
	{
	  puts ("loading \"testobj5.so\" succeeded, OK");

	  if (dlopen ("testobj5.so", RTLD_LAZY | RTLD_NOLOAD) == NULL)
	    {
	      printf ("cannot open \"testobj5.so\": %s\n", dlerror ());
	      result = 1;
	    }
	  else
	    puts ("loading \"testobj5.so\" with RTLD_NOLOAD succeeded, OK");

	  if (dlclose (p) != 0)
	    {
	      printf ("cannot close \"testobj5.so\": %s\n", dlerror ());
	      result = 1;
	    }
	  else
	    puts ("closing \"testobj5.so\" succeeded, OK");
	}
    }

  return result;
}


extern int foo (int a);
int
foo (int a)
{
  return 42 + a;
}