code.delx.au - pulseaudio/blob - src/modules/module-null-sink.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of PulseAudio.
   5
   6   Copyright 2004-2006 Lennart Poettering
   7
   8   PulseAudio is free software; you can redistribute it and/or modify
   9   it under the terms of the GNU Lesser General Public License as published
  10   by the Free Software Foundation; either version 2 of the License,
  11   or (at your option) any later version.
  12
  13   PulseAudio is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser General Public License
  19   along with PulseAudio; if not, write to the Free Software
  20   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  21   USA.
  22 ***/
  23
  24 #ifdef HAVE_CONFIG_H
  25 #include <config.h>
  26 #endif
  27
  28 #include <stdlib.h>
  29 #include <sys/stat.h>
  30 #include <stdio.h>
  31 #include <errno.h>
  32 #include <string.h>
  33 #include <fcntl.h>
  34 #include <unistd.h>
  35 #include <limits.h>
  36
  37 #include <pulse/timeval.h>
  38 #include <pulse/xmalloc.h>
  39
  40 #include <pulsecore/macro.h>
  41 #include <pulsecore/sink.h>
  42 #include <pulsecore/module.h>
  43 #include <pulsecore/core-util.h>
  44 #include <pulsecore/core-error.h>
  45 #include <pulsecore/modargs.h>
  46 #include <pulsecore/log.h>
  47 #include <pulsecore/thread.h>
  48 #include <pulsecore/thread-mq.h>
  49 #include <pulsecore/rtpoll.h>
  50 #include <pulsecore/rtclock.h>
  51
  52 #include "module-null-sink-symdef.h"
  53
  54 PA_MODULE_AUTHOR("Lennart Poettering")
  55 PA_MODULE_DESCRIPTION("Clocked NULL sink")
  56 PA_MODULE_VERSION(PACKAGE_VERSION)
  57 PA_MODULE_USAGE(
  58         "format=<sample format> "
  59         "channels=<number of channels> "
  60         "rate=<sample rate> "
  61         "sink_name=<name of sink>"
  62         "channel_map=<channel map>"
  63         "description=<description for the sink>")
  64
  65 #define DEFAULT_SINK_NAME "null"
  66
  67 struct userdata {
  68     pa_core *core;
  69     pa_module *module;
  70     pa_sink *sink;
  71
  72     pa_thread *thread;
  73     pa_thread_mq thread_mq;
  74     pa_rtpoll *rtpoll;
  75
  76     size_t block_size;
  77
  78     struct timespec timestamp;
  79 };
  80
  81 static const char* const valid_modargs[] = {
  82     "rate",
  83     "format",
  84     "channels",
  85     "sink_name",
  86     "channel_map",
  87     "description",
  88     NULL
  89 };
  90
  91 static int sink_process_msg(pa_msgobject *o, int code, void *data, int64_t offset, pa_memchunk *chunk) {
  92     struct userdata *u = PA_SINK(o)->userdata;
  93
  94     switch (code) {
  95         case PA_SINK_MESSAGE_SET_STATE:
  96
  97             if (PA_PTR_TO_UINT(data) == PA_SINK_RUNNING)
  98                 pa_rtclock_get(&u->timestamp);
  99
 100             break;
 101
 102         case PA_SINK_MESSAGE_GET_LATENCY: {
 103             struct timespec now;
 104
 105             pa_rtclock_get(&now);
 106
 107             if (pa_timespec_cmp(&u->timestamp, &now) > 0)
 108                 *((pa_usec_t*) data) = 0;
 109             else
 110                 *((pa_usec_t*) data) = pa_timespec_diff(&u->timestamp, &now);
 111             break;
 112         }
 113     }
 114
 115     return pa_sink_process_msg(o, code, data, offset, chunk);
 116 }
 117
 118 static void thread_func(void *userdata) {
 119     struct userdata *u = userdata;
 120
 121     pa_assert(u);
 122
 123     pa_log_debug("Thread starting up");
 124
 125     pa_thread_mq_install(&u->thread_mq);
 126     pa_rtpoll_install(u->rtpoll);
 127
 128     pa_rtclock_get(&u->timestamp);
 129
 130     for (;;) {
 131         int ret;
 132
 133         /* Render some data and drop it immediately */
 134         if (u->sink->thread_info.state == PA_SINK_RUNNING) {
 135             struct timespec now;
 136
 137             pa_rtclock_get(&now);
 138
 139             if (pa_timespec_cmp(&u->timestamp, &now) <= 0) {
 140                 pa_sink_skip(u->sink, u->block_size);
 141                 pa_timespec_add(&u->timestamp, pa_bytes_to_usec(u->block_size, &u->sink->sample_spec));
 142             }
 143
 144             pa_rtpoll_set_timer_absolute(u->rtpoll, &u->timestamp);
 145         } else
 146             pa_rtpoll_set_timer_disabled(u->rtpoll);
 147
 148         /* Hmm, nothing to do. Let's sleep */
 149         if ((ret = pa_rtpoll_run(u->rtpoll, 1)) < 0)
 150             goto fail;
 151
 152         if (ret == 0)
 153             goto finish;
 154     }
 155
 156 fail:
 157     /* If this was no regular exit from the loop we have to continue
 158      * processing messages until we received PA_MESSAGE_SHUTDOWN */
 159     pa_asyncmsgq_post(u->thread_mq.outq, PA_MSGOBJECT(u->core), PA_CORE_MESSAGE_UNLOAD_MODULE, u->module, 0, NULL, NULL);
 160     pa_asyncmsgq_wait_for(u->thread_mq.inq, PA_MESSAGE_SHUTDOWN);
 161
 162 finish:
 163     pa_log_debug("Thread shutting down");
 164 }
 165
 166 int pa__init(pa_module*m) {
 167     struct userdata *u = NULL;
 168     pa_sample_spec ss;
 169     pa_channel_map map;
 170     pa_modargs *ma = NULL;
 171
 172     pa_assert(m);
 173
 174     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 175         pa_log("Failed to parse module arguments.");
 176         goto fail;
 177     }
 178
 179     ss = m->core->default_sample_spec;
 180     if (pa_modargs_get_sample_spec_and_channel_map(ma, &ss, &map, PA_CHANNEL_MAP_DEFAULT) < 0) {
 181         pa_log("Invalid sample format specification or channel map");
 182         goto fail;
 183     }
 184
 185     u = pa_xnew0(struct userdata, 1);
 186     u->core = m->core;
 187     u->module = m;
 188     m->userdata = u;
 189     pa_thread_mq_init(&u->thread_mq, m->core->mainloop);
 190     u->rtpoll = pa_rtpoll_new();
 191     pa_rtpoll_item_new_asyncmsgq(u->rtpoll, PA_RTPOLL_EARLY, u->thread_mq.inq);
 192
 193     if (!(u->sink = pa_sink_new(m->core, __FILE__, pa_modargs_get_value(ma, "sink_name", DEFAULT_SINK_NAME), 0, &ss, &map))) {
 194         pa_log("Failed to create sink.");
 195         goto fail;
 196     }
 197
 198     u->sink->parent.process_msg = sink_process_msg;
 199     u->sink->userdata = u;
 200     u->sink->flags = PA_SINK_LATENCY;
 201
 202     pa_sink_set_module(u->sink, m);
 203     pa_sink_set_asyncmsgq(u->sink, u->thread_mq.inq);
 204     pa_sink_set_rtpoll(u->sink, u->rtpoll);
 205     pa_sink_set_description(u->sink, pa_modargs_get_value(ma, "description", "NULL sink"));
 206
 207     u->block_size = pa_bytes_per_second(&ss) / 20; /* 50 ms */
 208     if (u->block_size <= 0)
 209         u->block_size = pa_frame_size(&ss);
 210
 211     if (!(u->thread = pa_thread_new(thread_func, u))) {
 212         pa_log("Failed to create thread.");
 213         goto fail;
 214     }
 215
 216     pa_sink_put(u->sink);
 217
 218     pa_modargs_free(ma);
 219
 220     return 0;
 221
 222 fail:
 223     if (ma)
 224         pa_modargs_free(ma);
 225
 226     pa__done(m);
 227
 228     return -1;
 229 }
 230
 231 void pa__done(pa_module*m) {
 232     struct userdata *u;
 233
 234     pa_assert(m);
 235
 236     if (!(u = m->userdata))
 237         return;
 238
 239     if (u->sink)
 240         pa_sink_unlink(u->sink);
 241
 242     if (u->thread) {
 243         pa_asyncmsgq_send(u->thread_mq.inq, NULL, PA_MESSAGE_SHUTDOWN, NULL, 0, NULL);
 244         pa_thread_free(u->thread);
 245     }
 246
 247     pa_thread_mq_done(&u->thread_mq);
 248
 249     if (u->sink)
 250         pa_sink_unref(u->sink);
 251
 252     if (u->rtpoll)
 253         pa_rtpoll_free(u->rtpoll);
 254
 255     pa_xfree(u);
 256 }