src/pulse/thread-mainloop.c

   1 /***
   2   This file is part of PulseAudio.
   3
   4   Copyright 2006 Lennart Poettering
   5   Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB
   6
   7   PulseAudio is free software; you can redistribute it and/or modify
   8   it under the terms of the GNU Lesser General Public License as published
   9   by the Free Software Foundation; either version 2 of the License,
  10   or (at your option) any later version.
  11
  12   PulseAudio is distributed in the hope that it will be useful, but
  13   WITHOUT ANY WARRANTY; without even the implied warranty of
  14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  15   General Public License for more details.
  16
  17   You should have received a copy of the GNU Lesser General Public License
  18   along with PulseAudio; if not, write to the Free Software
  19   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  20   USA.
  21 ***/
  22
  23 #ifdef HAVE_CONFIG_H
  24 #include <config.h>
  25 #endif
  26
  27 #include <signal.h>
  28 #include <stdio.h>
  29
  30 #ifdef HAVE_POLL_H
  31 #include <poll.h>
  32 #else
  33 #include <pulsecore/poll.h>
  34 #endif
  35
  36 #include <pulse/xmalloc.h>
  37 #include <pulse/mainloop.h>
  38 #include <pulse/i18n.h>
  39
  40 #include <pulsecore/log.h>
  41 #include <pulsecore/hashmap.h>
  42 #include <pulsecore/thread.h>
  43 #include <pulsecore/mutex.h>
  44 #include <pulsecore/macro.h>
  45
  46 #include "thread-mainloop.h"
  47
  48 struct pa_threaded_mainloop {
  49     pa_mainloop *real_mainloop;
  50     int n_waiting;
  51
  52     pa_thread* thread;
  53     pa_mutex* mutex;
  54     pa_cond* cond, *accept_cond;
  55 };
  56
  57 static inline int in_worker(pa_threaded_mainloop *m) {
  58     return pa_thread_self() == m->thread;
  59 }
  60
  61 static int poll_func(struct pollfd *ufds, unsigned long nfds, int timeout, void *userdata) {
  62     pa_mutex *mutex = userdata;
  63     int r;
  64
  65     pa_assert(mutex);
  66
  67     /* Before entering poll() we unlock the mutex, so that
  68      * avahi_simple_poll_quit() can succeed from another thread. */
  69
  70     pa_mutex_unlock(mutex);
  71     r = poll(ufds, nfds, timeout);
  72     pa_mutex_lock(mutex);
  73
  74     return r;
  75 }
  76
  77 static void thread(void *userdata) {
  78     pa_threaded_mainloop *m = userdata;
  79
  80 #ifndef OS_IS_WIN32
  81     sigset_t mask;
  82
  83     /* Make sure that signals are delivered to the main thread */
  84     sigfillset(&mask);
  85     pthread_sigmask(SIG_BLOCK, &mask, NULL);
  86 #endif
  87
  88     pa_mutex_lock(m->mutex);
  89
  90     pa_mainloop_run(m->real_mainloop, NULL);
  91
  92     pa_mutex_unlock(m->mutex);
  93 }
  94
  95 pa_threaded_mainloop *pa_threaded_mainloop_new(void) {
  96     pa_threaded_mainloop *m;
  97
  98     pa_init_i18n();
  99
 100     m = pa_xnew(pa_threaded_mainloop, 1);
 101
 102     if (!(m->real_mainloop = pa_mainloop_new())) {
 103         pa_xfree(m);
 104         return NULL;
 105     }
 106
 107     m->mutex = pa_mutex_new(TRUE, TRUE);
 108     m->cond = pa_cond_new();
 109     m->accept_cond = pa_cond_new();
 110     m->thread = NULL;
 111
 112     pa_mainloop_set_poll_func(m->real_mainloop, poll_func, m->mutex);
 113
 114     m->n_waiting = 0;
 115
 116     return m;
 117 }
 118
 119 void pa_threaded_mainloop_free(pa_threaded_mainloop* m) {
 120     pa_assert(m);
 121
 122     /* Make sure that this function is not called from the helper thread */
 123     pa_assert((m->thread && !pa_thread_is_running(m->thread)) || !in_worker(m));
 124
 125     pa_threaded_mainloop_stop(m);
 126
 127     if (m->thread)
 128         pa_thread_free(m->thread);
 129
 130     pa_mainloop_free(m->real_mainloop);
 131
 132     pa_mutex_free(m->mutex);
 133     pa_cond_free(m->cond);
 134     pa_cond_free(m->accept_cond);
 135
 136     pa_xfree(m);
 137 }
 138
 139 int pa_threaded_mainloop_start(pa_threaded_mainloop *m) {
 140     pa_assert(m);
 141
 142     pa_assert(!m->thread || !pa_thread_is_running(m->thread));
 143
 144     if (!(m->thread = pa_thread_new(thread, m)))
 145         return -1;
 146
 147     return 0;
 148 }
 149
 150 void pa_threaded_mainloop_stop(pa_threaded_mainloop *m) {
 151     pa_assert(m);
 152
 153     if (!m->thread || !pa_thread_is_running(m->thread))
 154         return;
 155
 156     /* Make sure that this function is not called from the helper thread */
 157     pa_assert(!in_worker(m));
 158
 159     pa_mutex_lock(m->mutex);
 160     pa_mainloop_quit(m->real_mainloop, 0);
 161     pa_mutex_unlock(m->mutex);
 162
 163     pa_thread_join(m->thread);
 164 }
 165
 166 void pa_threaded_mainloop_lock(pa_threaded_mainloop *m) {
 167     pa_assert(m);
 168
 169     /* Make sure that this function is not called from the helper thread */
 170     pa_assert(!m->thread || !pa_thread_is_running(m->thread) || !in_worker(m));
 171
 172     pa_mutex_lock(m->mutex);
 173 }
 174
 175 void pa_threaded_mainloop_unlock(pa_threaded_mainloop *m) {
 176     pa_assert(m);
 177
 178     /* Make sure that this function is not called from the helper thread */
 179     pa_assert(!m->thread || !pa_thread_is_running(m->thread) || !in_worker(m));
 180
 181     pa_mutex_unlock(m->mutex);
 182 }
 183
 184 void pa_threaded_mainloop_signal(pa_threaded_mainloop *m, int wait_for_accept) {
 185     pa_assert(m);
 186
 187     pa_cond_signal(m->cond, 1);
 188
 189     if (wait_for_accept && m->n_waiting > 0)
 190         pa_cond_wait(m->accept_cond, m->mutex);
 191 }
 192
 193 void pa_threaded_mainloop_wait(pa_threaded_mainloop *m) {
 194     pa_assert(m);
 195
 196     /* Make sure that this function is not called from the helper thread */
 197     pa_assert(!m->thread || !pa_thread_is_running(m->thread) || !in_worker(m));
 198
 199     m->n_waiting ++;
 200
 201     pa_cond_wait(m->cond, m->mutex);
 202
 203     pa_assert(m->n_waiting > 0);
 204     m->n_waiting --;
 205 }
 206
 207 void pa_threaded_mainloop_accept(pa_threaded_mainloop *m) {
 208     pa_assert(m);
 209
 210     /* Make sure that this function is not called from the helper thread */
 211     pa_assert(!m->thread || !pa_thread_is_running(m->thread) || !in_worker(m));
 212
 213     pa_cond_signal(m->accept_cond, 0);
 214 }
 215
 216 int pa_threaded_mainloop_get_retval(pa_threaded_mainloop *m) {
 217     pa_assert(m);
 218
 219     return pa_mainloop_get_retval(m->real_mainloop);
 220 }
 221
 222 pa_mainloop_api* pa_threaded_mainloop_get_api(pa_threaded_mainloop*m) {
 223     pa_assert(m);
 224
 225     return pa_mainloop_get_api(m->real_mainloop);
 226 }
 227
 228 int pa_threaded_mainloop_in_thread(pa_threaded_mainloop *m) {
 229     pa_assert(m);
 230
 231     return m->thread && pa_thread_self() == m->thread;
 232 }