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

   1 /***
   2   This file is part of PulseAudio.
   3
   4   Copyright 2004-2008 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, 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 <stdlib.h>
  27 #include <sys/stat.h>
  28 #include <stdio.h>
  29 #include <errno.h>
  30 #include <string.h>
  31 #include <fcntl.h>
  32 #include <unistd.h>
  33 #include <limits.h>
  34
  35 #include <pulse/rtclock.h>
  36 #include <pulse/timeval.h>
  37 #include <pulse/xmalloc.h>
  38
  39 #include <pulsecore/macro.h>
  40 #include <pulsecore/sink.h>
  41 #include <pulsecore/module.h>
  42 #include <pulsecore/core-rtclock.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
  51 #include "module-null-sink-symdef.h"
  52
  53 PA_MODULE_AUTHOR("Lennart Poettering");
  54 PA_MODULE_DESCRIPTION("Clocked NULL sink");
  55 PA_MODULE_VERSION(PACKAGE_VERSION);
  56 PA_MODULE_LOAD_ONCE(FALSE);
  57 PA_MODULE_USAGE(
  58         "sink_name=<name of sink> "
  59         "sink_properties=<properties for the sink> "
  60         "format=<sample format> "
  61         "rate=<sample rate> "
  62         "channels=<number of channels> "
  63         "channel_map=<channel map>");
  64
  65 #define DEFAULT_SINK_NAME "null"
  66 #define BLOCK_USEC (PA_USEC_PER_SEC * 2)
  67
  68 struct userdata {
  69     pa_core *core;
  70     pa_module *module;
  71     pa_sink *sink;
  72
  73     pa_thread *thread;
  74     pa_thread_mq thread_mq;
  75     pa_rtpoll *rtpoll;
  76
  77     pa_usec_t block_usec;
  78     pa_usec_t timestamp;
  79 };
  80
  81 static const char* const valid_modargs[] = {
  82     "sink_name",
  83     "sink_properties",
  84     "format",
  85     "rate",
  86     "channels",
  87     "channel_map",
  88     "description", /* supported for compatibility reasons, made redundant by sink_properties= */
  89     NULL
  90 };
  91
  92 static int sink_process_msg(
  93         pa_msgobject *o,
  94         int code,
  95         void *data,
  96         int64_t offset,
  97         pa_memchunk *chunk) {
  98
  99     struct userdata *u = PA_SINK(o)->userdata;
 100
 101     switch (code) {
 102         case PA_SINK_MESSAGE_SET_STATE:
 103
 104             if (PA_PTR_TO_UINT(data) == PA_SINK_RUNNING)
 105                 u->timestamp = pa_rtclock_now();
 106
 107             break;
 108
 109         case PA_SINK_MESSAGE_GET_LATENCY: {
 110             pa_usec_t now;
 111
 112             now = pa_rtclock_now();
 113             *((pa_usec_t*) data) = u->timestamp > now ? u->timestamp - now : 0ULL;
 114
 115             return 0;
 116         }
 117     }
 118
 119     return pa_sink_process_msg(o, code, data, offset, chunk);
 120 }
 121
 122 static void sink_update_requested_latency_cb(pa_sink *s) {
 123     struct userdata *u;
 124     size_t nbytes;
 125
 126     pa_sink_assert_ref(s);
 127     pa_assert_se(u = s->userdata);
 128
 129     u->block_usec = pa_sink_get_requested_latency_within_thread(s);
 130
 131     if (u->block_usec == (pa_usec_t) -1)
 132         u->block_usec = s->thread_info.max_latency;
 133
 134     nbytes = pa_usec_to_bytes(u->block_usec, &s->sample_spec);
 135     pa_sink_set_max_rewind_within_thread(s, nbytes);
 136     pa_sink_set_max_request_within_thread(s, nbytes);
 137 }
 138
 139 static void process_rewind(struct userdata *u, pa_usec_t now) {
 140     size_t rewind_nbytes, in_buffer;
 141     pa_usec_t delay;
 142
 143     pa_assert(u);
 144
 145     /* Figure out how much we shall rewind and reset the counter */
 146     rewind_nbytes = u->sink->thread_info.rewind_nbytes;
 147     u->sink->thread_info.rewind_nbytes = 0;
 148
 149     pa_assert(rewind_nbytes > 0);
 150     pa_log_debug("Requested to rewind %lu bytes.", (unsigned long) rewind_nbytes);
 151
 152     if (u->timestamp <= now)
 153         goto do_nothing;
 154
 155     delay = u->timestamp - now;
 156     in_buffer = pa_usec_to_bytes(delay, &u->sink->sample_spec);
 157
 158     if (in_buffer <= 0)
 159         goto do_nothing;
 160
 161     if (rewind_nbytes > in_buffer)
 162         rewind_nbytes = in_buffer;
 163
 164     pa_sink_process_rewind(u->sink, rewind_nbytes);
 165     u->timestamp -= pa_bytes_to_usec(rewind_nbytes, &u->sink->sample_spec);
 166
 167     pa_log_debug("Rewound %lu bytes.", (unsigned long) rewind_nbytes);
 168     return;
 169
 170 do_nothing:
 171
 172     pa_sink_process_rewind(u->sink, 0);
 173 }
 174
 175 static void process_render(struct userdata *u, pa_usec_t now) {
 176     size_t ate = 0;
 177
 178     pa_assert(u);
 179
 180     /* This is the configured latency. Sink inputs connected to us
 181     might not have a single frame more than the maxrequest value
 182     queed. Hence: at maximum read this many bytes from the sink
 183     inputs. */
 184
 185     /* Fill the buffer up the the latency size */
 186     while (u->timestamp < now + u->block_usec) {
 187         pa_memchunk chunk;
 188
 189         pa_sink_render(u->sink, u->sink->thread_info.max_request, &chunk);
 190         pa_memblock_unref(chunk.memblock);
 191
 192 /*         pa_log_debug("Ate %lu bytes.", (unsigned long) chunk.length); */
 193         u->timestamp += pa_bytes_to_usec(chunk.length, &u->sink->sample_spec);
 194
 195         ate += chunk.length;
 196
 197         if (ate >= u->sink->thread_info.max_request)
 198             break;
 199     }
 200
 201 /*     pa_log_debug("Ate in sum %lu bytes (of %lu)", (unsigned long) ate, (unsigned long) nbytes); */
 202 }
 203
 204 static void thread_func(void *userdata) {
 205     struct userdata *u = userdata;
 206
 207     pa_assert(u);
 208
 209     pa_log_debug("Thread starting up");
 210
 211     pa_thread_mq_install(&u->thread_mq);
 212
 213     u->timestamp = pa_rtclock_now();
 214
 215     for (;;) {
 216         int ret;
 217
 218         /* Render some data and drop it immediately */
 219         if (PA_SINK_IS_OPENED(u->sink->thread_info.state)) {
 220             pa_usec_t now;
 221
 222             now = pa_rtclock_now();
 223
 224             if (u->sink->thread_info.rewind_requested) {
 225                 if (u->sink->thread_info.rewind_nbytes > 0)
 226                     process_rewind(u, now);
 227                 else
 228                     pa_sink_process_rewind(u->sink, 0);
 229             }
 230
 231             if (u->timestamp <= now)
 232                 process_render(u, now);
 233
 234             pa_rtpoll_set_timer_absolute(u->rtpoll, u->timestamp);
 235         } else
 236             pa_rtpoll_set_timer_disabled(u->rtpoll);
 237
 238         /* Hmm, nothing to do. Let's sleep */
 239         if ((ret = pa_rtpoll_run(u->rtpoll, TRUE)) < 0)
 240             goto fail;
 241
 242         if (ret == 0)
 243             goto finish;
 244     }
 245
 246 fail:
 247     /* If this was no regular exit from the loop we have to continue
 248      * processing messages until we received PA_MESSAGE_SHUTDOWN */
 249     pa_asyncmsgq_post(u->thread_mq.outq, PA_MSGOBJECT(u->core), PA_CORE_MESSAGE_UNLOAD_MODULE, u->module, 0, NULL, NULL);
 250     pa_asyncmsgq_wait_for(u->thread_mq.inq, PA_MESSAGE_SHUTDOWN);
 251
 252 finish:
 253     pa_log_debug("Thread shutting down");
 254 }
 255
 256 int pa__init(pa_module*m) {
 257     struct userdata *u = NULL;
 258     pa_sample_spec ss;
 259     pa_channel_map map;
 260     pa_modargs *ma = NULL;
 261     pa_sink_new_data data;
 262     size_t nbytes;
 263
 264     pa_assert(m);
 265
 266     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 267         pa_log("Failed to parse module arguments.");
 268         goto fail;
 269     }
 270
 271     ss = m->core->default_sample_spec;
 272     map = m->core->default_channel_map;
 273     if (pa_modargs_get_sample_spec_and_channel_map(ma, &ss, &map, PA_CHANNEL_MAP_DEFAULT) < 0) {
 274         pa_log("Invalid sample format specification or channel map");
 275         goto fail;
 276     }
 277
 278     m->userdata = u = pa_xnew0(struct userdata, 1);
 279     u->core = m->core;
 280     u->module = m;
 281     u->rtpoll = pa_rtpoll_new();
 282     pa_thread_mq_init(&u->thread_mq, m->core->mainloop, u->rtpoll);
 283
 284     pa_sink_new_data_init(&data);
 285     data.driver = __FILE__;
 286     data.module = m;
 287     pa_sink_new_data_set_name(&data, pa_modargs_get_value(ma, "sink_name", DEFAULT_SINK_NAME));
 288     pa_sink_new_data_set_sample_spec(&data, &ss);
 289     pa_sink_new_data_set_channel_map(&data, &map);
 290     pa_proplist_sets(data.proplist, PA_PROP_DEVICE_DESCRIPTION, pa_modargs_get_value(ma, "description", "Null Output"));
 291     pa_proplist_sets(data.proplist, PA_PROP_DEVICE_CLASS, "abstract");
 292
 293     if (pa_modargs_get_proplist(ma, "sink_properties", data.proplist, PA_UPDATE_REPLACE) < 0) {
 294         pa_log("Invalid properties");
 295         pa_sink_new_data_done(&data);
 296         goto fail;
 297     }
 298
 299     u->sink = pa_sink_new(m->core, &data, PA_SINK_LATENCY|PA_SINK_DYNAMIC_LATENCY);
 300     pa_sink_new_data_done(&data);
 301
 302     if (!u->sink) {
 303         pa_log("Failed to create sink object.");
 304         goto fail;
 305     }
 306
 307     u->sink->parent.process_msg = sink_process_msg;
 308     u->sink->update_requested_latency = sink_update_requested_latency_cb;
 309     u->sink->userdata = u;
 310
 311     pa_sink_set_asyncmsgq(u->sink, u->thread_mq.inq);
 312     pa_sink_set_rtpoll(u->sink, u->rtpoll);
 313
 314     u->block_usec = BLOCK_USEC;
 315     nbytes = pa_usec_to_bytes(u->block_usec, &u->sink->sample_spec);
 316     pa_sink_set_max_rewind(u->sink, nbytes);
 317     pa_sink_set_max_request(u->sink, nbytes);
 318
 319     if (!(u->thread = pa_thread_new(thread_func, u))) {
 320         pa_log("Failed to create thread.");
 321         goto fail;
 322     }
 323
 324     pa_sink_put(u->sink);
 325
 326     pa_modargs_free(ma);
 327
 328     return 0;
 329
 330 fail:
 331     if (ma)
 332         pa_modargs_free(ma);
 333
 334     pa__done(m);
 335
 336     return -1;
 337 }
 338
 339 int pa__get_n_used(pa_module *m) {
 340     struct userdata *u;
 341
 342     pa_assert(m);
 343     pa_assert_se(u = m->userdata);
 344
 345     return pa_sink_linked_by(u->sink);
 346 }
 347
 348 void pa__done(pa_module*m) {
 349     struct userdata *u;
 350
 351     pa_assert(m);
 352
 353     if (!(u = m->userdata))
 354         return;
 355
 356     if (u->sink)
 357         pa_sink_unlink(u->sink);
 358
 359     if (u->thread) {
 360         pa_asyncmsgq_send(u->thread_mq.inq, NULL, PA_MESSAGE_SHUTDOWN, NULL, 0, NULL);
 361         pa_thread_free(u->thread);
 362     }
 363
 364     pa_thread_mq_done(&u->thread_mq);
 365
 366     if (u->sink)
 367         pa_sink_unref(u->sink);
 368
 369     if (u->rtpoll)
 370         pa_rtpoll_free(u->rtpoll);
 371
 372     pa_xfree(u);
 373 }