nptl/tst-tls7mod.c

   1 /* Copyright (C) 2013 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    <http://www.gnu.org/licenses/>.  */
  17
  18 /* Dynamic module with TLS to be accessed by a signal handler to check safety
  19    of that mode. */
  20
  21 #include <semaphore.h>
  22 #include <signal.h>
  23 #include <unistd.h>
  24
  25 /* This is an unlikely value to see in incorrectly initialized TLS
  26    block -- make sure we're initialized properly. */
  27 static __thread intptr_t tls_data = 0xdeadbeef;
  28
  29 void
  30 action (int signo, siginfo_t *info, void *ignored)
  31 {
  32   if (tls_data != 0xdeadbeef)
  33     {
  34       write (STDOUT_FILENO, "wrong TLS value\n", 17);
  35       _exit (1);
  36     }
  37
  38   /* arbitrary choice, just write something unique-ish. */
  39   tls_data = (intptr_t) info;
  40 }