1 /***
2 This file is part of PulseAudio.
3
4 Copyright 2006 Lennart Poettering
5
6 PulseAudio is free software; you can redistribute it and/or modify
7 it under the terms of the GNU Lesser General Public License as published
8 by the Free Software Foundation; either version 2.1 of the License,
9 or (at your option) any later version.
10
11 PulseAudio is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public License
17 along with PulseAudio; if not, see <http://www.gnu.org/licenses/>.
18 ***/
19
20 #ifdef HAVE_CONFIG_H
21 #include <config.h>
22 #endif
23
24 #include <pthread.h>
25 #include <errno.h>
26
27 #include <pulse/xmalloc.h>
28
29 #include <pulsecore/core-error.h>
30 #include <pulsecore/macro.h>
31
32 #include "mutex.h"
33
34 #include "log/audio_log.h"
35
36 struct pa_mutex {
37 pthread_mutex_t mutex;
38 };
39
40 struct pa_cond {
41 pthread_cond_t cond;
42 };
43
pa_mutex_new(bool recursive,bool inherit_priority)44 pa_mutex* pa_mutex_new(bool recursive, bool inherit_priority) {
45 pa_mutex *m;
46 pthread_mutexattr_t attr;
47 #ifdef HAVE_PTHREAD_PRIO_INHERIT
48 int r;
49 #endif
50
51 pa_assert_se(pthread_mutexattr_init(&attr) == 0);
52
53 if (recursive)
54 pa_assert_se(pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE) == 0);
55
56 #ifdef HAVE_PTHREAD_PRIO_INHERIT
57 if (inherit_priority) {
58 r = pthread_mutexattr_setprotocol(&attr, PTHREAD_PRIO_INHERIT);
59 pa_assert(r == 0 || r == ENOTSUP);
60 }
61 #endif
62
63 m = pa_xnew(pa_mutex, 1);
64
65 #ifndef HAVE_PTHREAD_PRIO_INHERIT
66 pa_assert_se(pthread_mutex_init(&m->mutex, &attr) == 0);
67
68 #else
69 if ((r = pthread_mutex_init(&m->mutex, &attr))) {
70
71 /* If this failed, then this was probably due to non-available
72 * priority inheritance. In which case we fall back to normal
73 * mutexes. */
74 pa_assert(r == ENOTSUP && inherit_priority);
75
76 pa_assert_se(pthread_mutexattr_setprotocol(&attr, PTHREAD_PRIO_NONE) == 0);
77 pa_assert_se(pthread_mutex_init(&m->mutex, &attr) == 0);
78 }
79 #endif
80
81 return m;
82 }
83
pa_mutex_free(pa_mutex * m)84 void pa_mutex_free(pa_mutex *m) {
85 pa_assert(m);
86
87 pa_assert_se(pthread_mutex_destroy(&m->mutex) == 0);
88 pa_xfree(m);
89 }
90
pa_mutex_lock(pa_mutex * m)91 void pa_mutex_lock(pa_mutex *m) {
92 pa_assert(m);
93
94 pa_assert_se(pthread_mutex_lock(&m->mutex) == 0);
95 }
96
pa_mutex_try_lock(pa_mutex * m)97 bool pa_mutex_try_lock(pa_mutex *m) {
98 int r;
99 pa_assert(m);
100
101 if ((r = pthread_mutex_trylock(&m->mutex)) != 0) {
102 pa_assert(r == EBUSY);
103 return false;
104 }
105
106 return true;
107 }
108
pa_mutex_unlock(pa_mutex * m)109 void pa_mutex_unlock(pa_mutex *m) {
110 int err;
111
112 pa_assert(m);
113
114 if ((err = pthread_mutex_unlock(&m->mutex)) != 0) {
115 AUDIO_ERR_LOG("pthread_mutex_unlock() failed: %{public}s", pa_cstrerror(err));
116 pa_assert_not_reached();
117 }
118 }
119
pa_cond_new(void)120 pa_cond *pa_cond_new(void) {
121 pa_cond *c;
122
123 c = pa_xnew(pa_cond, 1);
124 pa_assert_se(pthread_cond_init(&c->cond, NULL) == 0);
125 return c;
126 }
127
pa_cond_free(pa_cond * c)128 void pa_cond_free(pa_cond *c) {
129 pa_assert(c);
130
131 pa_assert_se(pthread_cond_destroy(&c->cond) == 0);
132 pa_xfree(c);
133 }
134
pa_cond_signal(pa_cond * c,int broadcast)135 void pa_cond_signal(pa_cond *c, int broadcast) {
136 pa_assert(c);
137
138 if (broadcast)
139 pa_assert_se(pthread_cond_broadcast(&c->cond) == 0);
140 else
141 pa_assert_se(pthread_cond_signal(&c->cond) == 0);
142 }
143
pa_cond_wait(pa_cond * c,pa_mutex * m)144 int pa_cond_wait(pa_cond *c, pa_mutex *m) {
145 pa_assert(c);
146 pa_assert(m);
147
148 return pthread_cond_wait(&c->cond, &m->mutex);
149 }
150
pa_static_mutex_get(pa_static_mutex * s,bool recursive,bool inherit_priority)151 pa_mutex* pa_static_mutex_get(pa_static_mutex *s, bool recursive, bool inherit_priority) {
152 pa_mutex *m;
153
154 pa_assert(s);
155
156 /* First, check if already initialized and short cut */
157 if ((m = pa_atomic_ptr_load(&s->ptr)))
158 return m;
159
160 /* OK, not initialized, so let's allocate, and fill in */
161 m = pa_mutex_new(recursive, inherit_priority);
162 if ((pa_atomic_ptr_cmpxchg(&s->ptr, NULL, m)))
163 return m;
164
165 pa_mutex_free(m);
166
167 /* Him, filling in failed, so someone else must have filled in
168 * already */
169 pa_assert_se(m = pa_atomic_ptr_load(&s->ptr));
170 return m;
171 }
172