sysdeps/pthread/tst-cleanup2.c

   1 /* Copyright (C) 2003-2024 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <setjmp.h>
  19 #include <signal.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <sys/types.h>
  23
  24 static sigjmp_buf jmpbuf;
  25
  26 static void
  27 sig_handler (int signo)
  28 {
  29   siglongjmp (jmpbuf, 1);
  30 }
  31
  32 static int
  33 do_test (void)
  34 {
  35   char *p = NULL;
  36   /* gcc can overwrite the success written value by scheduling instructions
  37      around sprintf.  It is allowed to do this since according to C99 the first
  38      argument of sprintf is a character array and NULL is not a valid character
  39      array.  Mark the return value as volatile so that it gets reloaded on
  40      return.  */
  41   volatile int ret = 0;
  42
  43   if (signal (SIGSEGV, &sig_handler) == SIG_ERR)
  44     {
  45       perror ("installing SIGSEGV handler");
  46       return 1;
  47     }
  48
  49   puts ("Attempting to sprintf to null ptr");
  50   if (setjmp (jmpbuf))
  51     {
  52       puts ("Exiting main...");
  53       return ret;
  54     }
  55
  56   sprintf (p, "This should segv\n");
  57
  58   return 1;
  59 }
  60
  61 #define TEST_FUNCTION do_test ()
  62 #include "../test-skeleton.c"