1  /* Test getauxval from a dynamic library after static dlopen.
       2     Copyright (C) 2021-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; if not, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #include <dlfcn.h>
      20  #include <errno.h>
      21  #include <stdio.h>
      22  #include <support/check.h>
      23  #include <support/xdlfcn.h>
      24  #include <sys/auxv.h>
      25  
      26  unsigned long getauxval_wrapper (unsigned long type, int *errnop);
      27  
      28  static int
      29  do_test (void)
      30  {
      31    unsigned long outer_random = getauxval (AT_RANDOM);
      32    if (outer_random == 0)
      33      FAIL_UNSUPPORTED ("getauxval does not support AT_RANDOM");
      34  
      35    unsigned long missing_auxv_type;
      36    for (missing_auxv_type = AT_RANDOM + 1; ; ++missing_auxv_type)
      37      {
      38        errno = 0;
      39        if (getauxval (missing_auxv_type) == 0 && errno != 0)
      40          {
      41            TEST_COMPARE (errno, ENOENT);
      42            break;
      43          }
      44      }
      45    printf ("info: first missing type: %lu\n", missing_auxv_type);
      46  
      47    void *handle = xdlopen ("tst-auxvalmod.so", RTLD_LAZY);
      48    void *ptr = xdlsym (handle, "getauxval_wrapper");
      49  
      50    __typeof__ (getauxval_wrapper) *wrapper = ptr;
      51    int inner_errno = 0;
      52    unsigned long inner_random = wrapper (AT_RANDOM, &inner_errno);
      53    TEST_COMPARE (outer_random, inner_random);
      54  
      55    inner_errno = 0;
      56    TEST_COMPARE (wrapper (missing_auxv_type, &inner_errno), 0);
      57    TEST_COMPARE (inner_errno, ENOENT);
      58  
      59    TEST_COMPARE (getauxval (AT_HWCAP), wrapper (AT_HWCAP, &inner_errno));
      60    TEST_COMPARE (getauxval (AT_HWCAP2), wrapper (AT_HWCAP2, &inner_errno));
      61  
      62    xdlclose (handle);
      63    return 0;
      64  }
      65  
      66  #include <support/test-driver.c>