/* Test recursive mutexes. Copyright (C) 2000-2018 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 . */ #define _GNU_SOURCE #include #include #include #include #define THREADS 10 int foo; void * thr (void *arg) { int i; pthread_mutex_lock (arg); foo = pthread_self (); for (i = 0; i < 500; i++) pthread_mutex_lock (arg); for (i = 0; i < 500; i++) pthread_mutex_unlock (arg); assert (foo == pthread_self ()); pthread_mutex_unlock (arg); return 0; } int main (int argc, char **argv) { error_t err; int i; pthread_t tid[THREADS]; pthread_mutexattr_t mattr; pthread_mutex_t mutex; err = pthread_mutexattr_init (&mattr); if (err) error (1, err, "pthread_mutexattr_init"); err = pthread_mutexattr_settype (&mattr, PTHREAD_MUTEX_RECURSIVE); if (err) error (1, err, "pthread_mutexattr_settype"); err = pthread_mutex_init (&mutex, &mattr); if (err) error (1, err, "pthread_mutex_init"); err = pthread_mutexattr_destroy (&mattr); if (err) error (1, err, "pthread_mutexattr_destroy"); pthread_mutex_lock (&mutex); pthread_mutex_lock (&mutex); pthread_mutex_unlock (&mutex); pthread_mutex_unlock (&mutex); for (i = 0; i < THREADS; i++) { err = pthread_create (&tid[i], 0, thr, &mutex); if (err) error (1, err, "pthread_create (%d)", i); } for (i = 0; i < THREADS; i++) { void *ret; err = pthread_join (tid[i], &ret); if (err) error (1, err, "pthread_join"); assert (ret == 0); } err = pthread_mutex_destroy (&mutex); if (err) error (1, err, "pthread_mutex_destroy"); return 0; }