elf/unload.c

   1 /* Test for unloading (really unmapping) of objects.  By Franz Sirl.
   2    This test does not have to passed in all dlopen() et.al. implementation
   3    since it is not required the unloading actually happens.  But we
   4    require it for glibc.  */
   5
   6 #include <dlfcn.h>
   7 #include <link.h>
   8 #include <mcheck.h>
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11
  12 #define MAPS ((struct link_map *) _r_debug.r_map)
  13
  14 #define OUT \
  15   for (map = MAPS; map != NULL; map = map->l_next)                            \
  16     if (map->l_type == lt_loaded)                                             \
  17       printf ("name = \"%s\", direct_opencount = %d\n",                       \
  18               map->l_name, (int) map->l_direct_opencount);                    \
  19   fflush (stdout)
  20
  21 typedef struct
  22 {
  23   void *next;
  24 } strct;
  25
  26 int
  27 main (void)
  28 {
  29    void *sohandle;
  30    strct *testdat;
  31    int ret;
  32    int result = 0;
  33    struct link_map *map;
  34
  35    mtrace ();
  36
  37    puts ("\nBefore");
  38    OUT;
  39
  40    sohandle = dlopen ("unloadmod.so", RTLD_NOW | RTLD_GLOBAL);
  41    if (sohandle == NULL)
  42      {
  43        printf ("*** first dlopen failed: %s\n", dlerror ());
  44        exit (1);
  45      }
  46
  47    puts ("\nAfter loading unloadmod.so");
  48    OUT;
  49
  50    testdat = dlsym (sohandle, "testdat");
  51    testdat->next = (void *) -1;
  52
  53    ret = dlclose (sohandle);
  54    if (ret != 0)
  55      {
  56        puts ("*** first dlclose failed");
  57        result = 1;
  58      }
  59
  60    puts ("\nAfter closing unloadmod.so");
  61    OUT;
  62
  63    sohandle = dlopen ("unloadmod.so", RTLD_NOW | RTLD_GLOBAL);
  64    if (sohandle == NULL)
  65      {
  66        printf ("*** second dlopen failed: %s\n", dlerror ());
  67        exit (1);
  68      }
  69
  70    puts ("\nAfter loading unloadmod.so the second time");
  71    OUT;
  72
  73    testdat = dlsym (sohandle, "testdat");
  74    if (testdat->next == (void *) -1)
  75      {
  76        puts ("*** testdat->next == (void *) -1");
  77        result = 1;
  78      }
  79
  80    ret = dlclose (sohandle);
  81    if (ret != 0)
  82      {
  83        puts ("*** second dlclose failed");
  84        result = 1;
  85      }
  86
  87    puts ("\nAfter closing unloadmod.so again");
  88    OUT;
  89
  90    return result;
  91 }