code.delx.au - pulseaudio/blob - src/pulsecore/thread-posix.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of PulseAudio.
   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 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, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <assert.h>
  27 #include <pthread.h>
  28 #include <atomic_ops.h>
  29
  30 #include <pulse/xmalloc.h>
  31
  32 #include "thread.h"
  33
  34 #define ASSERT_SUCCESS(x) do { \
  35     int _r = (x); \
  36     assert(_r == 0); \
  37 } while(0)
  38
  39 struct pa_thread {
  40     pthread_t id;
  41     pa_thread_func_t thread_func;
  42     void *userdata;
  43     AO_t running;
  44 };
  45
  46 struct pa_tls {
  47     pthread_key_t key;
  48 };
  49
  50 static pa_tls *thread_tls;
  51 static pthread_once_t thread_tls_once = PTHREAD_ONCE_INIT;
  52
  53 static void thread_tls_once_func(void) {
  54     thread_tls = pa_tls_new(NULL);
  55     assert(thread_tls);
  56 }
  57
  58 static void* internal_thread_func(void *userdata) {
  59     pa_thread *t = userdata;
  60     assert(t);
  61
  62     t->id = pthread_self();
  63
  64     ASSERT_SUCCESS(pthread_once(&thread_tls_once, thread_tls_once_func));
  65     pa_tls_set(thread_tls, t);
  66
  67     AO_store_release_write(&t->running, 1);
  68     t->thread_func(t->userdata);
  69     AO_store_release_write(&t->running, 0);
  70
  71     return NULL;
  72 }
  73
  74 pa_thread* pa_thread_new(pa_thread_func_t thread_func, void *userdata) {
  75     pa_thread *t;
  76
  77     t = pa_xnew(pa_thread, 1);
  78     t->thread_func = thread_func;
  79     t->userdata = userdata;
  80
  81     if (pthread_create(&t->id, NULL, internal_thread_func, t) < 0) {
  82         pa_xfree(t);
  83         return NULL;
  84     }
  85
  86     return t;
  87 }
  88
  89 int pa_thread_is_running(pa_thread *t) {
  90     assert(t);
  91
  92     return !!AO_load_acquire_read(&t->running);
  93 }
  94
  95 void pa_thread_free(pa_thread *t) {
  96     assert(t);
  97
  98     pa_thread_join(t);
  99     pa_xfree(t);
 100 }
 101
 102 int pa_thread_join(pa_thread *t) {
 103     assert(t);
 104
 105     return pthread_join(t->id, NULL);
 106 }
 107
 108 pa_thread* pa_thread_self(void) {
 109     ASSERT_SUCCESS(pthread_once(&thread_tls_once, thread_tls_once_func));
 110     return pa_tls_get(thread_tls);
 111 }
 112
 113 pa_tls* pa_tls_new(pa_free_cb_t free_cb) {
 114     pa_tls *t;
 115
 116     t = pa_xnew(pa_tls, 1);
 117
 118     if (pthread_key_create(&t->key, free_cb) < 0) {
 119         pa_xfree(t);
 120         return NULL;
 121     }
 122
 123     return t;
 124 }
 125
 126 void pa_tls_free(pa_tls *t) {
 127     assert(t);
 128
 129     ASSERT_SUCCESS(pthread_key_delete(t->key));
 130     pa_xfree(t);
 131 }
 132
 133 void *pa_tls_get(pa_tls *t) {
 134     assert(t);
 135
 136     return pthread_getspecific(t->key);
 137 }
 138
 139 void *pa_tls_set(pa_tls *t, void *userdata) {
 140     void *r;
 141
 142     r = pthread_getspecific(t->key);
 143     ASSERT_SUCCESS(pthread_setspecific(t->key, userdata));
 144     return r;
 145 }
 146