1 /*
2 * Copyright 2009-2012 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 #include "event2/event-config.h"
27 #include "evconfig-private.h"
28
29 /* With glibc we need to define _GNU_SOURCE to get PTHREAD_MUTEX_RECURSIVE.
30 * This comes from evconfig-private.h
31 */
32 #include <pthread.h>
33
34 struct event_base;
35 #include "event2/thread.h"
36
37 #include <stdlib.h>
38 #include <string.h>
39 #include "mm-internal.h"
40 #include "evthread-internal.h"
41
42 static pthread_mutexattr_t attr_recursive;
43
44 static void *
evthread_posix_lock_alloc(unsigned locktype)45 evthread_posix_lock_alloc(unsigned locktype)
46 {
47 pthread_mutexattr_t *attr = NULL;
48 pthread_mutex_t *lock = mm_malloc(sizeof(pthread_mutex_t));
49 if (!lock)
50 return NULL;
51 if (locktype & EVTHREAD_LOCKTYPE_RECURSIVE)
52 attr = &attr_recursive;
53 if (pthread_mutex_init(lock, attr)) {
54 mm_free(lock);
55 return NULL;
56 }
57 return lock;
58 }
59
60 static void
evthread_posix_lock_free(void * lock_,unsigned locktype)61 evthread_posix_lock_free(void *lock_, unsigned locktype)
62 {
63 pthread_mutex_t *lock = lock_;
64 pthread_mutex_destroy(lock);
65 mm_free(lock);
66 }
67
68 static int
evthread_posix_lock(unsigned mode,void * lock_)69 evthread_posix_lock(unsigned mode, void *lock_)
70 {
71 pthread_mutex_t *lock = lock_;
72 if (mode & EVTHREAD_TRY)
73 return pthread_mutex_trylock(lock);
74 else
75 return pthread_mutex_lock(lock);
76 }
77
78 static int
evthread_posix_unlock(unsigned mode,void * lock_)79 evthread_posix_unlock(unsigned mode, void *lock_)
80 {
81 pthread_mutex_t *lock = lock_;
82 return pthread_mutex_unlock(lock);
83 }
84
85 static unsigned long
evthread_posix_get_id(void)86 evthread_posix_get_id(void)
87 {
88 union {
89 pthread_t thr;
90 #if EVENT__SIZEOF_PTHREAD_T > EVENT__SIZEOF_LONG
91 ev_uint64_t id;
92 #else
93 unsigned long id;
94 #endif
95 } r;
96 #if EVENT__SIZEOF_PTHREAD_T < EVENT__SIZEOF_LONG
97 memset(&r, 0, sizeof(r));
98 #endif
99 r.thr = pthread_self();
100 return (unsigned long)r.id;
101 }
102
103 static void *
evthread_posix_cond_alloc(unsigned condflags)104 evthread_posix_cond_alloc(unsigned condflags)
105 {
106 pthread_cond_t *cond = mm_malloc(sizeof(pthread_cond_t));
107 if (!cond)
108 return NULL;
109 if (pthread_cond_init(cond, NULL)) {
110 mm_free(cond);
111 return NULL;
112 }
113 return cond;
114 }
115
116 static void
evthread_posix_cond_free(void * cond_)117 evthread_posix_cond_free(void *cond_)
118 {
119 pthread_cond_t *cond = cond_;
120 pthread_cond_destroy(cond);
121 mm_free(cond);
122 }
123
124 static int
evthread_posix_cond_signal(void * cond_,int broadcast)125 evthread_posix_cond_signal(void *cond_, int broadcast)
126 {
127 pthread_cond_t *cond = cond_;
128 int r;
129 if (broadcast)
130 r = pthread_cond_broadcast(cond);
131 else
132 r = pthread_cond_signal(cond);
133 return r ? -1 : 0;
134 }
135
136 static int
evthread_posix_cond_wait(void * cond_,void * lock_,const struct timeval * tv)137 evthread_posix_cond_wait(void *cond_, void *lock_, const struct timeval *tv)
138 {
139 int r;
140 pthread_cond_t *cond = cond_;
141 pthread_mutex_t *lock = lock_;
142
143 if (tv) {
144 struct timeval now, abstime;
145 struct timespec ts;
146 evutil_gettimeofday(&now, NULL);
147 evutil_timeradd(&now, tv, &abstime);
148 ts.tv_sec = abstime.tv_sec;
149 ts.tv_nsec = abstime.tv_usec*1000;
150 r = pthread_cond_timedwait(cond, lock, &ts);
151 if (r == ETIMEDOUT)
152 return 1;
153 else if (r)
154 return -1;
155 else
156 return 0;
157 } else {
158 r = pthread_cond_wait(cond, lock);
159 return r ? -1 : 0;
160 }
161 }
162
163 int
evthread_use_pthreads(void)164 evthread_use_pthreads(void)
165 {
166 struct evthread_lock_callbacks cbs = {
167 EVTHREAD_LOCK_API_VERSION,
168 EVTHREAD_LOCKTYPE_RECURSIVE,
169 evthread_posix_lock_alloc,
170 evthread_posix_lock_free,
171 evthread_posix_lock,
172 evthread_posix_unlock
173 };
174 struct evthread_condition_callbacks cond_cbs = {
175 EVTHREAD_CONDITION_API_VERSION,
176 evthread_posix_cond_alloc,
177 evthread_posix_cond_free,
178 evthread_posix_cond_signal,
179 evthread_posix_cond_wait
180 };
181 /* Set ourselves up to get recursive locks. */
182 if (pthread_mutexattr_init(&attr_recursive))
183 return -1;
184 if (pthread_mutexattr_settype(&attr_recursive, PTHREAD_MUTEX_RECURSIVE))
185 return -1;
186
187 evthread_set_lock_callbacks(&cbs);
188 evthread_set_condition_callbacks(&cond_cbs);
189 evthread_set_id_callback(evthread_posix_get_id);
190 return 0;
191 }
192