1 /* 2 * Copyright 2009 Niels Provos and Nick Mathewson 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 3. The name of the author may not be used to endorse or promote products 13 * derived from this software without specific prior written permission. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 #ifdef HAVE_CONFIG_H 27 #include "event-config.h" 28 #endif 29 30 /* With glibc we need to define this to get PTHREAD_MUTEX_RECURSIVE. */ 31 #define _GNU_SOURCE 32 #include <pthread.h> 33 34 struct event_base; 35 #include <event2/thread.h> 36 37 #include "mm-internal.h" 38 39 static pthread_mutexattr_t attr_recursive; 40 41 static void * 42 evthread_posix_lock_create(void) 43 { 44 pthread_mutex_t *lock = mm_malloc(sizeof(pthread_mutex_t)); 45 if (!lock) 46 return NULL; 47 if (pthread_mutex_init(lock, &attr_recursive)) { 48 mm_free(lock); 49 return NULL; 50 } 51 return lock; 52 } 53 54 static void 55 evthread_posix_lock_free(void *_lock) 56 { 57 pthread_mutex_t *lock = _lock; 58 pthread_mutex_destroy(lock); 59 mm_free(lock); 60 } 61 62 static void 63 evthread_posix_lock(int mode, void *_lock) 64 { 65 pthread_mutex_t *lock = _lock; 66 if (0 != (mode & EVTHREAD_LOCK)) 67 pthread_mutex_lock(lock); 68 else 69 pthread_mutex_unlock(lock); 70 } 71 72 static unsigned long 73 evthread_posix_get_id(void) 74 { 75 union { 76 pthread_t thr; 77 unsigned long id; 78 } r; 79 r.thr = pthread_self(); 80 return r.id; 81 } 82 83 int 84 evthread_use_pthreads(void) 85 { 86 /* Set ourselves up to get recursive locks. */ 87 pthread_mutexattr_init(&attr_recursive); 88 pthread_mutexattr_settype(&attr_recursive, PTHREAD_MUTEX_RECURSIVE); 89 90 evthread_set_lock_create_callbacks( 91 evthread_posix_lock_create, 92 evthread_posix_lock_free); 93 evthread_set_locking_callback(evthread_posix_lock); 94 evthread_set_id_callback(evthread_posix_get_id); 95 return -1; 96 } 97