| /* Helper for exit/dlclose race test (Bug 22180). |
| Copyright (C) 2017-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <stdio.h> |
| #include <stdbool.h> |
| #include <stdlib.h> |
| #include <semaphore.h> |
| #include <unistd.h> |
| #include <support/check.h> |
| #include <support/xthread.h> |
| |
| /* Semaphore defined in executable to ensure we have a happens-before |
| between the first function starting and exit being called. */ |
| extern sem_t order1; |
| |
| /* Semaphore defined in executable to ensure we have a happens-before |
| between the second function starting and the first function returning. */ |
| extern sem_t order2; |
| |
| /* glibc function for registering DSO-specific exit functions. */ |
| extern int __cxa_atexit (void (*func) (void *), void *arg, void *dso_handle); |
| |
| /* Hidden compiler handle to this shared object. */ |
| extern void *__dso_handle __attribute__ ((__weak__)); |
| |
| static void |
| first (void *start) |
| { |
| /* Let the exiting thread run. */ |
| sem_post (&order1); |
| |
| /* Wait for exiting thread to finish. */ |
| sem_wait (&order2); |
| |
| printf ("first\n"); |
| } |
| |
| static void |
| second (void *start) |
| { |
| /* We may be called from different threads. |
| This lock protects called. */ |
| static pthread_mutex_t mtx = PTHREAD_MUTEX_INITIALIZER; |
| static bool called = false; |
| |
| xpthread_mutex_lock (&mtx); |
| if (called) |
| FAIL_EXIT1 ("second called twice!"); |
| |
| called = true; |
| xpthread_mutex_unlock (&mtx); |
| |
| printf ("second\n"); |
| } |
| |
| |
| __attribute__ ((constructor)) static void |
| constructor (void) |
| { |
| sem_init (&order1, 0, 0); |
| sem_init (&order2, 0, 0); |
| __cxa_atexit (second, NULL, __dso_handle); |
| __cxa_atexit (first, NULL, __dso_handle); |
| } |