external/bsd/libevent/dist/evthread_pthread.c

   1 /*      $NetBSD: evthread_pthread.c,v 1.1.1.1 2013/04/11 16:43:25 christos Exp $        */
   2 /*
   3  * Copyright 2009-2012 Niels Provos and Nick Mathewson
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. The name of the author may not be used to endorse or promote products
  14  *    derived from this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27 #include "event2/event-config.h"
  28 #include <sys/cdefs.h>
  29 __RCSID("$NetBSD: evthread_pthread.c,v 1.1.1.1 2013/04/11 16:43:25 christos Exp $");
  30
  31 /* With glibc we need to define this to get PTHREAD_MUTEX_RECURSIVE. */
  32 #define _GNU_SOURCE
  33 #include <pthread.h>
  34
  35 struct event_base;
  36 #include "event2/thread.h"
  37
  38 #include <stdlib.h>
  39 #include <string.h>
  40 #include "mm-internal.h"
  41 #include "evthread-internal.h"
  42
  43 static pthread_mutexattr_t attr_recursive;
  44
  45 static void *
  46 evthread_posix_lock_alloc(unsigned locktype)
  47 {
  48         pthread_mutexattr_t *attr = NULL;
  49         pthread_mutex_t *lock = mm_malloc(sizeof(pthread_mutex_t));
  50         if (!lock)
  51                 return NULL;
  52         if (locktype & EVTHREAD_LOCKTYPE_RECURSIVE)
  53                 attr = &attr_recursive;
  54         if (pthread_mutex_init(lock, attr)) {
  55                 mm_free(lock);
  56                 return NULL;
  57         }
  58         return lock;
  59 }
  60
  61 static void
  62 evthread_posix_lock_free(void *_lock, unsigned locktype)
  63 {
  64         pthread_mutex_t *lock = _lock;
  65         pthread_mutex_destroy(lock);
  66         mm_free(lock);
  67 }
  68
  69 static int
  70 evthread_posix_lock(unsigned mode, void *_lock)
  71 {
  72         pthread_mutex_t *lock = _lock;
  73         if (mode & EVTHREAD_TRY)
  74                 return pthread_mutex_trylock(lock);
  75         else
  76                 return pthread_mutex_lock(lock);
  77 }
  78
  79 static int
  80 evthread_posix_unlock(unsigned mode, void *_lock)
  81 {
  82         pthread_mutex_t *lock = _lock;
  83         return pthread_mutex_unlock(lock);
  84 }
  85
  86 static unsigned long
  87 evthread_posix_get_id(void)
  88 {
  89         union {
  90                 pthread_t thr;
  91 #if _EVENT_SIZEOF_PTHREAD_T > _EVENT_SIZEOF_LONG
  92                 ev_uint64_t id;
  93 #else
  94                 unsigned long id;
  95 #endif
  96         } r;
  97 #if _EVENT_SIZEOF_PTHREAD_T < _EVENT_SIZEOF_LONG
  98         memset(&r, 0, sizeof(r));
  99 #endif
 100         r.thr = pthread_self();
 101         return (unsigned long)r.id;
 102 }
 103
 104 static void *
 105 evthread_posix_cond_alloc(unsigned condflags)
 106 {
 107         pthread_cond_t *cond = mm_malloc(sizeof(pthread_cond_t));
 108         if (!cond)
 109                 return NULL;
 110         if (pthread_cond_init(cond, NULL)) {
 111                 mm_free(cond);
 112                 return NULL;
 113         }
 114         return cond;
 115 }
 116
 117 static void
 118 evthread_posix_cond_free(void *_cond)
 119 {
 120         pthread_cond_t *cond = _cond;
 121         pthread_cond_destroy(cond);
 122         mm_free(cond);
 123 }
 124
 125 static int
 126 evthread_posix_cond_signal(void *_cond, int broadcast)
 127 {
 128         pthread_cond_t *cond = _cond;
 129         int r;
 130         if (broadcast)
 131                 r = pthread_cond_broadcast(cond);
 132         else
 133                 r = pthread_cond_signal(cond);
 134         return r ? -1 : 0;
 135 }
 136
 137 static int
 138 evthread_posix_cond_wait(void *_cond, void *_lock, const struct timeval *tv)
 139 {
 140         int r;
 141         pthread_cond_t *cond = _cond;
 142         pthread_mutex_t *lock = _lock;
 143
 144         if (tv) {
 145                 struct timeval now, abstime;
 146                 struct timespec ts;
 147                 evutil_gettimeofday(&now, NULL);
 148                 evutil_timeradd(&now, tv, &abstime);
 149                 ts.tv_sec = abstime.tv_sec;
 150                 ts.tv_nsec = abstime.tv_usec*1000;
 151                 r = pthread_cond_timedwait(cond, lock, &ts);
 152                 if (r == ETIMEDOUT)
 153                         return 1;
 154                 else if (r)
 155                         return -1;
 156                 else
 157                         return 0;
 158         } else {
 159                 r = pthread_cond_wait(cond, lock);
 160                 return r ? -1 : 0;
 161         }
 162 }
 163
 164 int
 165 evthread_use_pthreads(void)
 166 {
 167         struct evthread_lock_callbacks cbs = {
 168                 EVTHREAD_LOCK_API_VERSION,
 169                 EVTHREAD_LOCKTYPE_RECURSIVE,
 170                 evthread_posix_lock_alloc,
 171                 evthread_posix_lock_free,
 172                 evthread_posix_lock,
 173                 evthread_posix_unlock
 174         };
 175         struct evthread_condition_callbacks cond_cbs = {
 176                 EVTHREAD_CONDITION_API_VERSION,
 177                 evthread_posix_cond_alloc,
 178                 evthread_posix_cond_free,
 179                 evthread_posix_cond_signal,
 180                 evthread_posix_cond_wait
 181         };
 182         /* Set ourselves up to get recursive locks. */
 183         if (pthread_mutexattr_init(&attr_recursive))
 184                 return -1;
 185         if (pthread_mutexattr_settype(&attr_recursive, PTHREAD_MUTEX_RECURSIVE))
 186                 return -1;
 187
 188         evthread_set_lock_callbacks(&cbs);
 189         evthread_set_condition_callbacks(&cond_cbs);
 190         evthread_set_id_callback(evthread_posix_get_id);
 191         return 0;
 192 }