1  /* Verify atexit, on_exit, etc. abort on NULL function pointer.
       2     Copyright (C) 2018-2023 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  
      20  #include <assert.h>
      21  #include <signal.h>
      22  #include <stdlib.h>
      23  #include <string.h>
      24  #include <support/capture_subprocess.h>
      25  #include <support/check.h>
      26  #include <support/support.h>
      27  #include <support/test-driver.h>
      28  
      29  extern int __cxa_atexit (void (*func) (void *), void *arg, void *d);
      30  extern int __cxa_at_quick_exit (void (*func) (void *), void *arg, void *d);
      31  
      32  /* GCC "knows" that atexit and on_exit should not be called with NULL
      33     function pointer, and emits diagnostics if we try to do so.
      34     Presumably it could emit a trap and drop the call altogether.
      35  
      36     The aliases below are intended to bypass this.  */
      37  
      38  extern int atexit_alias (void (*) (void)) __asm__ ("atexit");
      39  extern int at_quick_exit_alias (void (*) (void)) __asm__ ("at_quick_exit");
      40  extern int on_exit_alias (void (*) (void), void *) __asm__ ("on_exit");
      41  
      42  
      43  static void
      44  test_bz20544_atexit (void *closure)
      45  {
      46    atexit_alias (NULL);  /* Should assert.  */
      47    exit (EXIT_FAILURE);
      48  }
      49  
      50  static void
      51  test_bz20544_at_quick_exit (void *closure)
      52  {
      53    at_quick_exit_alias (NULL);  /* Should assert.  */
      54    exit (EXIT_FAILURE);
      55  }
      56  
      57  static void
      58  test_bz20544_on_exit (void *closure)
      59  {
      60    on_exit_alias (NULL, NULL);  /* Should assert.  */
      61    exit (EXIT_FAILURE);
      62  }
      63  
      64  static void
      65  test_bz20544_cxa_atexit (void *closure)
      66  {
      67    __cxa_atexit (NULL, NULL, NULL);  /* Should assert.  */
      68    exit (EXIT_FAILURE);
      69  }
      70  
      71  static void
      72  test_bz20544_cxa_at_quick_exit (void *closure)
      73  {
      74    __cxa_at_quick_exit (NULL, NULL, NULL);  /* Should assert.  */
      75    exit (EXIT_FAILURE);
      76  }
      77  
      78  static void
      79  test_one_fn (void (*test_fn) (void *))
      80  {
      81    const char expected_error[] = "assertion failed: func != NULL\n";
      82    struct support_capture_subprocess result;
      83    result = support_capture_subprocess (test_fn, NULL);
      84    support_capture_subprocess_check (&result, "bz20544", -SIGABRT,
      85                                      sc_allow_stderr);
      86  
      87    if (strstr (result.err.buffer, expected_error) == NULL)
      88      {
      89        support_record_failure ();
      90        printf ("Did not find expected string in error output:\n"
      91                "  expected: >>>%s<<<\n"
      92                "  actual:   >>>%s<<<\n",
      93                expected_error, result.err.buffer);
      94      }
      95  
      96    support_capture_subprocess_free (&result);
      97  }
      98  
      99  static int
     100  do_test (void)
     101  {
     102  #if defined (NDEBUG)
     103    FAIL_UNSUPPORTED ("Assertions disabled (NDEBUG). "
     104                      "Can't verify that assertions fire.");
     105  #endif
     106    test_one_fn (test_bz20544_atexit);
     107    test_one_fn (test_bz20544_at_quick_exit);
     108    test_one_fn (test_bz20544_on_exit);
     109    test_one_fn (test_bz20544_cxa_atexit);
     110    test_one_fn (test_bz20544_cxa_at_quick_exit);
     111  
     112    return 0;
     113  }
     114  
     115  #include <support/test-driver.c>