src/modules/module-loopback.c

   1 /***
   2     This file is part of PulseAudio.
   3
   4     Copyright 2009 Intel Corporation
   5     Contributor: Pierre-Louis Bossart <pierre-louis.bossart@intel.com>
   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 2.1 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 <stdio.h>
  28 #include <math.h>
  29
  30 #include <pulse/xmalloc.h>
  31
  32 #include <pulsecore/sink-input.h>
  33 #include <pulsecore/module.h>
  34 #include <pulsecore/modargs.h>
  35 #include <pulsecore/namereg.h>
  36 #include <pulsecore/log.h>
  37 #include <pulsecore/core-util.h>
  38
  39 #include <pulse/rtclock.h>
  40 #include <pulse/timeval.h>
  41
  42 #include "module-loopback-symdef.h"
  43
  44 PA_MODULE_AUTHOR("Pierre-Louis Bossart");
  45 PA_MODULE_DESCRIPTION("Loopback from source to sink");
  46 PA_MODULE_VERSION(PACKAGE_VERSION);
  47 PA_MODULE_LOAD_ONCE(FALSE);
  48 PA_MODULE_USAGE(
  49         "source=<source to connect to> "
  50         "sink=<sink to connect to> "
  51         "adjust_time=<how often to readjust rates in s> "
  52         "latency_msec=<latency in ms> "
  53         "format=<sample format> "
  54         "rate=<sample rate> "
  55         "channels=<number of channels> "
  56         "channel_map=<channel map> "
  57         "sink_input_name=<custom name for the sink input> "
  58         "source_output_name=<custom name for the source output> "
  59         "sink_input_role=<media.role for the sink input> "
  60         "source_output_role=<media.role for the source output>");
  61
  62 #define DEFAULT_LATENCY_MSEC 200
  63
  64 #define MEMBLOCKQ_MAXLENGTH (1024*1024*16)
  65
  66 #define DEFAULT_ADJUST_TIME_USEC (10*PA_USEC_PER_SEC)
  67
  68 struct userdata {
  69     pa_core *core;
  70     pa_module *module;
  71
  72     pa_sink_input *sink_input;
  73     pa_source_output *source_output;
  74
  75     pa_asyncmsgq *asyncmsgq;
  76     pa_memblockq *memblockq;
  77
  78     pa_rtpoll_item *rtpoll_item_read, *rtpoll_item_write;
  79
  80     pa_time_event *time_event;
  81     pa_usec_t adjust_time;
  82
  83     int64_t recv_counter;
  84     int64_t send_counter;
  85
  86     size_t skip;
  87     pa_usec_t latency;
  88
  89     pa_bool_t in_pop;
  90     size_t min_memblockq_length;
  91
  92     struct {
  93         int64_t send_counter;
  94         size_t source_output_buffer;
  95         pa_usec_t source_latency;
  96
  97         int64_t recv_counter;
  98         size_t sink_input_buffer;
  99         pa_usec_t sink_latency;
 100
 101         size_t min_memblockq_length;
 102         size_t max_request;
 103     } latency_snapshot;
 104 };
 105
 106 static const char* const valid_modargs[] = {
 107     "source",
 108     "sink",
 109     "latency_msec",
 110     "format",
 111     "rate",
 112     "channels",
 113     "channel_map",
 114     "sink_input_name",
 115     "source_output_name",
 116     "sink_input_role",
 117     "source_output_role",
 118     NULL,
 119 };
 120
 121 enum {
 122     SINK_INPUT_MESSAGE_POST = PA_SINK_INPUT_MESSAGE_MAX,
 123     SINK_INPUT_MESSAGE_REWIND,
 124     SINK_INPUT_MESSAGE_LATENCY_SNAPSHOT,
 125     SINK_INPUT_MESSAGE_MAX_REQUEST_CHANGED
 126 };
 127
 128 enum {
 129     SOURCE_OUTPUT_MESSAGE_LATENCY_SNAPSHOT
 130 };
 131
 132 /* Called from main context */
 133 static void teardown(struct userdata *u) {
 134     pa_assert(u);
 135     pa_assert_ctl_context();
 136
 137     if (u->sink_input)
 138         pa_sink_input_unlink(u->sink_input);
 139
 140     if (u->source_output)
 141         pa_source_output_unlink(u->source_output);
 142
 143     if (u->sink_input) {
 144         pa_sink_input_unref(u->sink_input);
 145         u->sink_input = NULL;
 146     }
 147
 148     if (u->source_output) {
 149         pa_source_output_unref(u->source_output);
 150         u->source_output = NULL;
 151     }
 152 }
 153
 154 /* Called from main context */
 155 static void adjust_rates(struct userdata *u) {
 156     size_t buffer, fs;
 157     uint32_t old_rate, base_rate, new_rate;
 158     pa_usec_t buffer_latency;
 159
 160     pa_assert(u);
 161     pa_assert_ctl_context();
 162
 163     pa_asyncmsgq_send(u->source_output->source->asyncmsgq, PA_MSGOBJECT(u->source_output), SOURCE_OUTPUT_MESSAGE_LATENCY_SNAPSHOT, NULL, 0, NULL);
 164     pa_asyncmsgq_send(u->sink_input->sink->asyncmsgq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_LATENCY_SNAPSHOT, NULL, 0, NULL);
 165
 166     buffer =
 167         u->latency_snapshot.sink_input_buffer +
 168         u->latency_snapshot.source_output_buffer;
 169
 170     if (u->latency_snapshot.recv_counter <= u->latency_snapshot.send_counter)
 171         buffer += (size_t) (u->latency_snapshot.send_counter - u->latency_snapshot.recv_counter);
 172     else
 173         buffer += PA_CLIP_SUB(buffer, (size_t) (u->latency_snapshot.recv_counter - u->latency_snapshot.send_counter));
 174
 175     buffer_latency = pa_bytes_to_usec(buffer, &u->sink_input->sample_spec);
 176
 177     pa_log_info("Loopback overall latency is %0.2f ms + %0.2f ms + %0.2f ms = %0.2f ms",
 178                 (double) u->latency_snapshot.sink_latency / PA_USEC_PER_MSEC,
 179                 (double) buffer_latency / PA_USEC_PER_MSEC,
 180                 (double) u->latency_snapshot.source_latency / PA_USEC_PER_MSEC,
 181                 ((double) u->latency_snapshot.sink_latency + buffer_latency + u->latency_snapshot.source_latency) / PA_USEC_PER_MSEC);
 182
 183     pa_log_info("Should buffer %zu bytes, buffered at minimum %zu bytes",
 184                 u->latency_snapshot.max_request*2,
 185                 u->latency_snapshot.min_memblockq_length);
 186
 187     fs = pa_frame_size(&u->sink_input->sample_spec);
 188     old_rate = u->sink_input->sample_spec.rate;
 189     base_rate = u->source_output->sample_spec.rate;
 190
 191     if (u->latency_snapshot.min_memblockq_length < u->latency_snapshot.max_request*2)
 192         new_rate = base_rate - (((u->latency_snapshot.max_request*2 - u->latency_snapshot.min_memblockq_length) / fs) *PA_USEC_PER_SEC)/u->adjust_time;
 193     else
 194         new_rate = base_rate + (((u->latency_snapshot.min_memblockq_length - u->latency_snapshot.max_request*2) / fs) *PA_USEC_PER_SEC)/u->adjust_time;
 195
 196     pa_log_info("Old rate %lu Hz, new rate %lu Hz", (unsigned long) old_rate, (unsigned long) new_rate);
 197
 198     pa_sink_input_set_rate(u->sink_input, new_rate);
 199
 200     pa_core_rttime_restart(u->core, u->time_event, pa_rtclock_now() + u->adjust_time);
 201 }
 202
 203 /* Called from main context */
 204 static void time_callback(pa_mainloop_api *a, pa_time_event *e, const struct timeval *t, void *userdata) {
 205     struct userdata *u = userdata;
 206
 207     pa_assert(u);
 208     pa_assert(a);
 209     pa_assert(u->time_event == e);
 210
 211     adjust_rates(u);
 212 }
 213
 214 /* Called from input thread context */
 215 static void source_output_push_cb(pa_source_output *o, const pa_memchunk *chunk) {
 216     struct userdata *u;
 217     pa_memchunk copy;
 218
 219     pa_source_output_assert_ref(o);
 220     pa_source_output_assert_io_context(o);
 221     pa_assert_se(u = o->userdata);
 222
 223     if (u->skip > chunk->length) {
 224         u->skip -= chunk->length;
 225         return;
 226     }
 227
 228     if (u->skip > 0) {
 229         copy = *chunk;
 230         copy.index += u->skip;
 231         copy.length -= u->skip;
 232         u->skip = 0;
 233
 234         chunk = &copy;
 235     }
 236
 237     pa_asyncmsgq_post(u->asyncmsgq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_POST, NULL, 0, chunk, NULL);
 238     u->send_counter += (int64_t) chunk->length;
 239 }
 240
 241 /* Called from input thread context */
 242 static void source_output_process_rewind_cb(pa_source_output *o, size_t nbytes) {
 243     struct userdata *u;
 244
 245     pa_source_output_assert_ref(o);
 246     pa_source_output_assert_io_context(o);
 247     pa_assert_se(u = o->userdata);
 248
 249     pa_asyncmsgq_post(u->asyncmsgq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_REWIND, NULL, (int64_t) nbytes, NULL, NULL);
 250     u->send_counter -= (int64_t) nbytes;
 251 }
 252
 253 /* Called from output thread context */
 254 static int source_output_process_msg_cb(pa_msgobject *obj, int code, void *data, int64_t offset, pa_memchunk *chunk) {
 255     struct userdata *u = PA_SOURCE_OUTPUT(obj)->userdata;
 256
 257     switch (code) {
 258
 259         case SOURCE_OUTPUT_MESSAGE_LATENCY_SNAPSHOT: {
 260             size_t length;
 261
 262             length = pa_memblockq_get_length(u->source_output->thread_info.delay_memblockq);
 263
 264             u->latency_snapshot.send_counter = u->send_counter;
 265             u->latency_snapshot.source_output_buffer = u->source_output->thread_info.resampler ? pa_resampler_result(u->source_output->thread_info.resampler, length) : length;
 266             u->latency_snapshot.source_latency = pa_source_get_latency_within_thread(u->source_output->source);
 267
 268             return 0;
 269         }
 270     }
 271
 272     return pa_source_output_process_msg(obj, code, data, offset, chunk);
 273 }
 274
 275 /* Called from output thread context */
 276 static void source_output_attach_cb(pa_source_output *o) {
 277     struct userdata *u;
 278
 279     pa_source_output_assert_ref(o);
 280     pa_source_output_assert_io_context(o);
 281     pa_assert_se(u = o->userdata);
 282
 283     u->rtpoll_item_write = pa_rtpoll_item_new_asyncmsgq_write(
 284             o->source->thread_info.rtpoll,
 285             PA_RTPOLL_LATE,
 286             u->asyncmsgq);
 287 }
 288
 289 /* Called from output thread context */
 290 static void source_output_detach_cb(pa_source_output *o) {
 291     struct userdata *u;
 292
 293     pa_source_output_assert_ref(o);
 294     pa_source_output_assert_io_context(o);
 295     pa_assert_se(u = o->userdata);
 296
 297     if (u->rtpoll_item_write) {
 298         pa_rtpoll_item_free(u->rtpoll_item_write);
 299         u->rtpoll_item_write = NULL;
 300     }
 301 }
 302
 303 /* Called from output thread context */
 304 static void source_output_state_change_cb(pa_source_output *o, pa_source_output_state_t state) {
 305     struct userdata *u;
 306
 307     pa_source_output_assert_ref(o);
 308     pa_source_output_assert_io_context(o);
 309     pa_assert_se(u = o->userdata);
 310
 311     if (PA_SOURCE_OUTPUT_IS_LINKED(state) && o->thread_info.state == PA_SOURCE_OUTPUT_INIT) {
 312
 313         u->skip = pa_usec_to_bytes(PA_CLIP_SUB(pa_source_get_latency_within_thread(o->source),
 314                                                u->latency),
 315                                    &o->sample_spec);
 316
 317         pa_log_info("Skipping %lu bytes", (unsigned long) u->skip);
 318     }
 319 }
 320
 321 /* Called from main thread */
 322 static void source_output_kill_cb(pa_source_output *o) {
 323     struct userdata *u;
 324
 325     pa_source_output_assert_ref(o);
 326     pa_assert_ctl_context();
 327     pa_assert_se(u = o->userdata);
 328
 329     teardown(u);
 330     pa_module_unload_request(u->module, TRUE);
 331 }
 332
 333 /* Called from main thread */
 334 static pa_bool_t source_output_may_move_to_cb(pa_source_output *o, pa_source *dest) {
 335     struct userdata *u;
 336
 337     pa_source_output_assert_ref(o);
 338     pa_assert_ctl_context();
 339     pa_assert_se(u = o->userdata);
 340
 341     return dest != u->sink_input->sink->monitor_source;
 342 }
 343
 344 /* Called from main thread */
 345 static void source_output_moving_cb(pa_source_output *o, pa_source *dest) {
 346     pa_proplist *p;
 347     const char *n;
 348     struct userdata *u;
 349
 350     pa_source_output_assert_ref(o);
 351     pa_assert_ctl_context();
 352     pa_assert_se(u = o->userdata);
 353
 354     p = pa_proplist_new();
 355     pa_proplist_setf(p, PA_PROP_MEDIA_NAME, "Loopback of %s", pa_strnull(pa_proplist_gets(dest->proplist, PA_PROP_DEVICE_DESCRIPTION)));
 356
 357     if ((n = pa_proplist_gets(dest->proplist, PA_PROP_DEVICE_ICON_NAME)))
 358         pa_proplist_sets(p, PA_PROP_MEDIA_ICON_NAME, n);
 359
 360     pa_sink_input_update_proplist(u->sink_input, PA_UPDATE_REPLACE, p);
 361     pa_proplist_free(p);
 362 }
 363
 364 /* Called from output thread context */
 365 static void update_min_memblockq_length(struct userdata *u) {
 366     size_t length;
 367
 368     pa_assert(u);
 369     pa_sink_input_assert_io_context(u->sink_input);
 370
 371     length = pa_memblockq_get_length(u->memblockq);
 372
 373     if (u->min_memblockq_length == (size_t) -1 ||
 374         length < u->min_memblockq_length)
 375         u->min_memblockq_length = length;
 376 }
 377
 378 /* Called from output thread context */
 379 static int sink_input_pop_cb(pa_sink_input *i, size_t nbytes, pa_memchunk *chunk) {
 380     struct userdata *u;
 381
 382     pa_sink_input_assert_ref(i);
 383     pa_sink_input_assert_io_context(i);
 384     pa_assert_se(u = i->userdata);
 385     pa_assert(chunk);
 386
 387     u->in_pop = TRUE;
 388     while (pa_asyncmsgq_process_one(u->asyncmsgq) > 0)
 389         ;
 390     u->in_pop = FALSE;
 391
 392     if (pa_memblockq_peek(u->memblockq, chunk) < 0) {
 393         pa_log_info("Coud not peek into queue");
 394         return -1;
 395     }
 396
 397     chunk->length = PA_MIN(chunk->length, nbytes);
 398     pa_memblockq_drop(u->memblockq, chunk->length);
 399
 400     update_min_memblockq_length(u);
 401
 402     return 0;
 403 }
 404
 405 /* Called from output thread context */
 406 static void sink_input_process_rewind_cb(pa_sink_input *i, size_t nbytes) {
 407     struct userdata *u;
 408
 409     pa_sink_input_assert_ref(i);
 410     pa_sink_input_assert_io_context(i);
 411     pa_assert_se(u = i->userdata);
 412
 413     pa_memblockq_rewind(u->memblockq, nbytes);
 414 }
 415
 416 /* Called from output thread context */
 417 static int sink_input_process_msg_cb(pa_msgobject *obj, int code, void *data, int64_t offset, pa_memchunk *chunk) {
 418     struct userdata *u = PA_SINK_INPUT(obj)->userdata;
 419
 420     switch (code) {
 421
 422         case PA_SINK_INPUT_MESSAGE_GET_LATENCY: {
 423              pa_usec_t *r = data;
 424
 425              pa_sink_input_assert_io_context(u->sink_input);
 426
 427             *r = pa_bytes_to_usec(pa_memblockq_get_length(u->memblockq), &u->sink_input->sample_spec);
 428
 429             /* Fall through, the default handler will add in the extra
 430              * latency added by the resampler */
 431             break;
 432         }
 433
 434         case SINK_INPUT_MESSAGE_POST:
 435
 436             pa_sink_input_assert_io_context(u->sink_input);
 437
 438             if (PA_SINK_IS_OPENED(u->sink_input->sink->thread_info.state))
 439                 pa_memblockq_push_align(u->memblockq, chunk);
 440             else
 441                 pa_memblockq_flush_write(u->memblockq, TRUE);
 442
 443             update_min_memblockq_length(u);
 444
 445             /* Is this the end of an underrun? Then let's start things
 446              * right-away */
 447             if (!u->in_pop &&
 448                 u->sink_input->thread_info.underrun_for > 0 &&
 449                 pa_memblockq_is_readable(u->memblockq)) {
 450
 451                 pa_log_debug("Requesting rewind due to end of underrun.");
 452                 pa_sink_input_request_rewind(u->sink_input,
 453                                              (size_t) (u->sink_input->thread_info.underrun_for == (size_t) -1 ? 0 : u->sink_input->thread_info.underrun_for),
 454                                              FALSE, TRUE, FALSE);
 455             }
 456
 457             u->recv_counter += (int64_t) chunk->length;
 458
 459             return 0;
 460
 461         case SINK_INPUT_MESSAGE_REWIND:
 462
 463             pa_sink_input_assert_io_context(u->sink_input);
 464
 465             if (PA_SINK_IS_OPENED(u->sink_input->sink->thread_info.state))
 466                 pa_memblockq_seek(u->memblockq, -offset, PA_SEEK_RELATIVE, TRUE);
 467             else
 468                 pa_memblockq_flush_write(u->memblockq, TRUE);
 469
 470             u->recv_counter -= offset;
 471
 472             update_min_memblockq_length(u);
 473
 474             return 0;
 475
 476         case SINK_INPUT_MESSAGE_LATENCY_SNAPSHOT: {
 477             size_t length;
 478
 479             update_min_memblockq_length(u);
 480
 481             length = pa_memblockq_get_length(u->sink_input->thread_info.render_memblockq);
 482
 483             u->latency_snapshot.recv_counter = u->recv_counter;
 484             u->latency_snapshot.sink_input_buffer =
 485                 pa_memblockq_get_length(u->memblockq) +
 486                 (u->sink_input->thread_info.resampler ? pa_resampler_request(u->sink_input->thread_info.resampler, length) : length);
 487             u->latency_snapshot.sink_latency = pa_sink_get_latency_within_thread(u->sink_input->sink);
 488
 489             u->latency_snapshot.max_request = pa_sink_input_get_max_request(u->sink_input);
 490
 491             u->latency_snapshot.min_memblockq_length = u->min_memblockq_length;
 492             u->min_memblockq_length = (size_t) -1;
 493
 494             return 0;
 495         }
 496
 497         case SINK_INPUT_MESSAGE_MAX_REQUEST_CHANGED: {
 498             /* This message is sent from the IO thread to the main
 499              * thread! So don't be confused. All the user cases above
 500              * are executed in thread context, but this one is not! */
 501
 502             pa_assert_ctl_context();
 503
 504             if (u->adjust_time > 0)
 505                 adjust_rates(u);
 506             return 0;
 507         }
 508     }
 509
 510     return pa_sink_input_process_msg(obj, code, data, offset, chunk);
 511 }
 512
 513 /* Called from output thread context */
 514 static void sink_input_attach_cb(pa_sink_input *i) {
 515     struct userdata *u;
 516
 517     pa_sink_input_assert_ref(i);
 518     pa_sink_input_assert_io_context(i);
 519     pa_assert_se(u = i->userdata);
 520
 521     u->rtpoll_item_read = pa_rtpoll_item_new_asyncmsgq_read(
 522             i->sink->thread_info.rtpoll,
 523             PA_RTPOLL_LATE,
 524             u->asyncmsgq);
 525
 526     pa_memblockq_set_prebuf(u->memblockq, pa_sink_input_get_max_request(i)*2);
 527     pa_memblockq_set_maxrewind(u->memblockq, pa_sink_input_get_max_rewind(i));
 528
 529     u->min_memblockq_length = (size_t) -1;
 530 }
 531
 532 /* Called from output thread context */
 533 static void sink_input_detach_cb(pa_sink_input *i) {
 534     struct userdata *u;
 535
 536     pa_sink_input_assert_ref(i);
 537     pa_sink_input_assert_io_context(i);
 538     pa_assert_se(u = i->userdata);
 539
 540     if (u->rtpoll_item_read) {
 541         pa_rtpoll_item_free(u->rtpoll_item_read);
 542         u->rtpoll_item_read = NULL;
 543     }
 544 }
 545
 546 /* Called from output thread context */
 547 static void sink_input_update_max_rewind_cb(pa_sink_input *i, size_t nbytes) {
 548     struct userdata *u;
 549
 550     pa_sink_input_assert_ref(i);
 551     pa_sink_input_assert_io_context(i);
 552     pa_assert_se(u = i->userdata);
 553
 554     pa_memblockq_set_maxrewind(u->memblockq, nbytes);
 555 }
 556
 557 /* Called from output thread context */
 558 static void sink_input_update_max_request_cb(pa_sink_input *i, size_t nbytes) {
 559     struct userdata *u;
 560
 561     pa_sink_input_assert_ref(i);
 562     pa_sink_input_assert_io_context(i);
 563     pa_assert_se(u = i->userdata);
 564
 565     pa_memblockq_set_prebuf(u->memblockq, nbytes*2);
 566     pa_log_info("Max request changed");
 567     pa_asyncmsgq_post(pa_thread_mq_get()->outq, PA_MSGOBJECT(u->sink_input), SINK_INPUT_MESSAGE_MAX_REQUEST_CHANGED, NULL, 0, NULL, NULL);
 568 }
 569
 570 /* Called from main thread */
 571 static void sink_input_kill_cb(pa_sink_input *i) {
 572     struct userdata *u;
 573
 574     pa_sink_input_assert_ref(i);
 575     pa_assert_ctl_context();
 576     pa_assert_se(u = i->userdata);
 577
 578     teardown(u);
 579     pa_module_unload_request(u->module, TRUE);
 580 }
 581
 582 /* Called from main thread */
 583 static void sink_input_moving_cb(pa_sink_input *i, pa_sink *dest) {
 584     struct userdata *u;
 585     pa_proplist *p;
 586     const char *n;
 587
 588     pa_sink_input_assert_ref(i);
 589     pa_assert_ctl_context();
 590     pa_assert_se(u = i->userdata);
 591
 592     p = pa_proplist_new();
 593     pa_proplist_setf(p, PA_PROP_MEDIA_NAME, "Loopback to %s", pa_strnull(pa_proplist_gets(dest->proplist, PA_PROP_DEVICE_DESCRIPTION)));
 594
 595     if ((n = pa_proplist_gets(dest->proplist, PA_PROP_DEVICE_ICON_NAME)))
 596         pa_proplist_sets(p, PA_PROP_MEDIA_ICON_NAME, n);
 597
 598     pa_source_output_update_proplist(u->source_output, PA_UPDATE_REPLACE, p);
 599     pa_proplist_free(p);
 600 }
 601
 602 /* Called from main thread */
 603 static pa_bool_t sink_input_may_move_to_cb(pa_sink_input *i, pa_sink *dest) {
 604     struct userdata *u;
 605
 606     pa_sink_input_assert_ref(i);
 607     pa_assert_ctl_context();
 608     pa_assert_se(u = i->userdata);
 609
 610     if (!u->source_output->source->monitor_of)
 611         return TRUE;
 612
 613     return dest != u->source_output->source->monitor_of;
 614 }
 615
 616 int pa__init(pa_module *m) {
 617     pa_modargs *ma = NULL;
 618     struct userdata *u;
 619     pa_sink *sink;
 620     pa_sink_input_new_data sink_input_data;
 621     pa_source *source;
 622     pa_source_output_new_data source_output_data;
 623     uint32_t latency_msec;
 624     pa_sample_spec ss;
 625     pa_channel_map map;
 626     pa_memchunk silence;
 627     uint32_t adjust_time_sec;
 628     const char *n;
 629
 630     pa_assert(m);
 631
 632     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 633         pa_log("Failed to parse module arguments");
 634         goto fail;
 635     }
 636
 637     if (!(source = pa_namereg_get(m->core, pa_modargs_get_value(ma, "source", NULL), PA_NAMEREG_SOURCE))) {
 638         pa_log("No such source.");
 639         goto fail;
 640     }
 641
 642     if (!(sink = pa_namereg_get(m->core, pa_modargs_get_value(ma, "sink", NULL), PA_NAMEREG_SINK))) {
 643         pa_log("No such sink.");
 644         goto fail;
 645     }
 646
 647     ss = sink->sample_spec;
 648     map = sink->channel_map;
 649     if (pa_modargs_get_sample_spec_and_channel_map(ma, &ss, &map, PA_CHANNEL_MAP_DEFAULT) < 0) {
 650         pa_log("Invalid sample format specification or channel map");
 651         goto fail;
 652     }
 653
 654     latency_msec = DEFAULT_LATENCY_MSEC;
 655     if (pa_modargs_get_value_u32(ma, "latency_msec", &latency_msec) < 0 || latency_msec < 1 || latency_msec > 2000) {
 656         pa_log("Invalid latency specification");
 657         goto fail;
 658     }
 659
 660     m->userdata = u = pa_xnew0(struct userdata, 1);
 661     u->core = m->core;
 662     u->module = m;
 663     u->latency = (pa_usec_t) latency_msec * PA_USEC_PER_MSEC;
 664
 665     adjust_time_sec = DEFAULT_ADJUST_TIME_USEC / PA_USEC_PER_SEC;
 666     if (pa_modargs_get_value_u32(ma, "adjust_time", &adjust_time_sec) < 0) {
 667         pa_log("Failed to parse adjust_time value");
 668         goto fail;
 669     }
 670
 671     if (adjust_time_sec != DEFAULT_ADJUST_TIME_USEC / PA_USEC_PER_SEC)
 672         u->adjust_time = adjust_time_sec * PA_USEC_PER_SEC;
 673     else
 674         u->adjust_time = DEFAULT_ADJUST_TIME_USEC;
 675
 676     pa_sink_input_new_data_init(&sink_input_data);
 677     sink_input_data.driver = __FILE__;
 678     sink_input_data.module = m;
 679     sink_input_data.sink = sink;
 680
 681     if ((n = pa_modargs_get_value(ma, "sink_input_name", NULL)))
 682         pa_proplist_sets(sink_input_data.proplist, PA_PROP_MEDIA_NAME, n);
 683     else
 684         pa_proplist_setf(sink_input_data.proplist, PA_PROP_MEDIA_NAME, "Loopback from %s",
 685                          pa_strnull(pa_proplist_gets(source->proplist, PA_PROP_DEVICE_DESCRIPTION)));
 686
 687     if ((n = pa_modargs_get_value(ma, "sink_input_role", NULL)))
 688         pa_proplist_sets(sink_input_data.proplist, PA_PROP_MEDIA_ROLE, n);
 689     else
 690         pa_proplist_sets(sink_input_data.proplist, PA_PROP_MEDIA_ROLE, "abstract");
 691
 692     if ((n = pa_proplist_gets(source->proplist, PA_PROP_DEVICE_ICON_NAME)))
 693         pa_proplist_sets(sink_input_data.proplist, PA_PROP_MEDIA_ICON_NAME, n);
 694
 695     pa_sink_input_new_data_set_sample_spec(&sink_input_data, &ss);
 696     pa_sink_input_new_data_set_channel_map(&sink_input_data, &map);
 697     sink_input_data.flags = PA_SINK_INPUT_VARIABLE_RATE;
 698
 699     pa_sink_input_new(&u->sink_input, m->core, &sink_input_data);
 700     pa_sink_input_new_data_done(&sink_input_data);
 701
 702     if (!u->sink_input)
 703         goto fail;
 704
 705     u->sink_input->parent.process_msg = sink_input_process_msg_cb;
 706     u->sink_input->pop = sink_input_pop_cb;
 707     u->sink_input->process_rewind = sink_input_process_rewind_cb;
 708     u->sink_input->kill = sink_input_kill_cb;
 709     u->sink_input->attach = sink_input_attach_cb;
 710     u->sink_input->detach = sink_input_detach_cb;
 711     u->sink_input->update_max_rewind = sink_input_update_max_rewind_cb;
 712     u->sink_input->update_max_request = sink_input_update_max_request_cb;
 713     u->sink_input->may_move_to = sink_input_may_move_to_cb;
 714     u->sink_input->moving = sink_input_moving_cb;
 715     u->sink_input->userdata = u;
 716
 717     pa_sink_input_set_requested_latency(u->sink_input, u->latency/3);
 718
 719     pa_source_output_new_data_init(&source_output_data);
 720     source_output_data.driver = __FILE__;
 721     source_output_data.module = m;
 722     source_output_data.source = source;
 723
 724     if ((n = pa_modargs_get_value(ma, "source_output_name", NULL)))
 725         pa_proplist_sets(source_output_data.proplist, PA_PROP_MEDIA_NAME, n);
 726     else
 727         pa_proplist_setf(source_output_data.proplist, PA_PROP_MEDIA_NAME, "Loopback to %s",
 728                          pa_strnull(pa_proplist_gets(sink->proplist, PA_PROP_DEVICE_DESCRIPTION)));
 729
 730     if ((n = pa_modargs_get_value(ma, "source_output_role", NULL)))
 731         pa_proplist_sets(source_output_data.proplist, PA_PROP_MEDIA_ROLE, n);
 732     else
 733         pa_proplist_sets(source_output_data.proplist, PA_PROP_MEDIA_ROLE, "abstract");
 734
 735     if ((n = pa_proplist_gets(sink->proplist, PA_PROP_DEVICE_ICON_NAME)))
 736         pa_proplist_sets(source_output_data.proplist, PA_PROP_MEDIA_ICON_NAME, n);
 737
 738     pa_source_output_new_data_set_sample_spec(&source_output_data, &ss);
 739     pa_sink_input_new_data_set_channel_map(&sink_input_data, &map);
 740
 741     pa_source_output_new(&u->source_output, m->core, &source_output_data);
 742     pa_source_output_new_data_done(&source_output_data);
 743
 744     if (!u->source_output)
 745         goto fail;
 746
 747     u->source_output->parent.process_msg = source_output_process_msg_cb;
 748     u->source_output->push = source_output_push_cb;
 749     u->source_output->process_rewind = source_output_process_rewind_cb;
 750     u->source_output->kill = source_output_kill_cb;
 751     u->source_output->attach = source_output_attach_cb;
 752     u->source_output->detach = source_output_detach_cb;
 753     u->source_output->state_change = source_output_state_change_cb;
 754     u->source_output->may_move_to = source_output_may_move_to_cb;
 755     u->source_output->moving = source_output_moving_cb;
 756     u->source_output->userdata = u;
 757
 758     pa_source_output_set_requested_latency(u->source_output, u->latency/3);
 759
 760     pa_sink_input_get_silence(u->sink_input, &silence);
 761     u->memblockq = pa_memblockq_new(
 762             0,                      /* idx */
 763             MEMBLOCKQ_MAXLENGTH,    /* maxlength */
 764             MEMBLOCKQ_MAXLENGTH,    /* tlength */
 765             pa_frame_size(&ss),     /* base */
 766             0,                      /* prebuf */
 767             0,                      /* minreq */
 768             0,                      /* maxrewind */
 769             &silence);              /* silence frame */
 770     pa_memblock_unref(silence.memblock);
 771
 772     u->asyncmsgq = pa_asyncmsgq_new(0);
 773
 774     pa_sink_input_put(u->sink_input);
 775     pa_source_output_put(u->source_output);
 776
 777     if (u->adjust_time > 0)
 778         u->time_event = pa_core_rttime_new(m->core, pa_rtclock_now() + u->adjust_time, time_callback, u);
 779
 780     pa_modargs_free(ma);
 781     return 0;
 782
 783 fail:
 784     if (ma)
 785         pa_modargs_free(ma);
 786
 787     pa__done(m);
 788
 789     return -1;
 790 }
 791
 792 void pa__done(pa_module*m) {
 793     struct userdata *u;
 794
 795     pa_assert(m);
 796
 797     if (!(u = m->userdata))
 798         return;
 799
 800     teardown(u);
 801
 802     if (u->memblockq)
 803         pa_memblockq_free(u->memblockq);
 804
 805     if (u->asyncmsgq)
 806         pa_asyncmsgq_unref(u->asyncmsgq);
 807
 808     if (u->time_event)
 809         u->core->mainloop->time_free(u->time_event);
 810
 811     pa_xfree(u);
 812 }