code.delx.au - pulseaudio/blob - src/pulsecore/sink.h

   1 #ifndef foopulsesinkhfoo
   2 #define foopulsesinkhfoo
   3
   4 /***
   5   This file is part of PulseAudio.
   6
   7   Copyright 2004-2006 Lennart Poettering
   8   Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB
   9
  10   PulseAudio is free software; you can redistribute it and/or modify
  11   it under the terms of the GNU Lesser General Public License as published
  12   by the Free Software Foundation; either version 2.1 of the License,
  13   or (at your option) any later version.
  14
  15   PulseAudio is distributed in the hope that it will be useful, but
  16   WITHOUT ANY WARRANTY; without even the implied warranty of
  17   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  18   General Public License for more details.
  19
  20   You should have received a copy of the GNU Lesser General Public License
  21   along with PulseAudio; if not, write to the Free Software
  22   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  23   USA.
  24 ***/
  25
  26 typedef struct pa_sink pa_sink;
  27 typedef struct pa_sink_volume_change pa_sink_volume_change;
  28
  29 #include <inttypes.h>
  30
  31 #include <pulse/def.h>
  32 #include <pulse/format.h>
  33 #include <pulse/sample.h>
  34 #include <pulse/channelmap.h>
  35 #include <pulse/volume.h>
  36
  37 #include <pulsecore/core.h>
  38 #include <pulsecore/idxset.h>
  39 #include <pulsecore/memchunk.h>
  40 #include <pulsecore/source.h>
  41 #include <pulsecore/module.h>
  42 #include <pulsecore/asyncmsgq.h>
  43 #include <pulsecore/msgobject.h>
  44 #include <pulsecore/rtpoll.h>
  45 #include <pulsecore/device-port.h>
  46 #include <pulsecore/card.h>
  47 #include <pulsecore/queue.h>
  48 #include <pulsecore/thread-mq.h>
  49 #include <pulsecore/sink-input.h>
  50
  51 #define PA_MAX_INPUTS_PER_SINK 256
  52
  53 /* Returns true if sink is linked: registered and accessible from client side. */
  54 static inline bool PA_SINK_IS_LINKED(pa_sink_state_t x) {
  55     return x == PA_SINK_RUNNING || x == PA_SINK_IDLE || x == PA_SINK_SUSPENDED;
  56 }
  57
  58 /* A generic definition for void callback functions */
  59 typedef void(*pa_sink_cb_t)(pa_sink *s);
  60
  61 struct pa_sink {
  62     pa_msgobject parent;
  63
  64     uint32_t index;
  65     pa_core *core;
  66
  67     pa_sink_state_t state;
  68     pa_sink_flags_t flags;
  69     pa_suspend_cause_t suspend_cause;
  70
  71     char *name;
  72     char *driver;                           /* may be NULL */
  73     pa_proplist *proplist;
  74
  75     pa_module *module;                      /* may be NULL */
  76     pa_card *card;                          /* may be NULL */
  77
  78     pa_sample_spec sample_spec;
  79     pa_channel_map channel_map;
  80     uint32_t default_sample_rate;
  81     uint32_t alternate_sample_rate;
  82
  83     pa_idxset *inputs;
  84     unsigned n_corked;
  85     pa_source *monitor_source;
  86     pa_sink_input *input_to_master;         /* non-NULL only for filter sinks */
  87
  88     pa_volume_t base_volume; /* shall be constant */
  89     unsigned n_volume_steps; /* shall be constant */
  90
  91     /* Also see http://pulseaudio.org/wiki/InternalVolumes */
  92     pa_cvolume reference_volume; /* The volume exported and taken as reference base for relative sink input volumes */
  93     pa_cvolume real_volume;      /* The volume that the hardware is configured to  */
  94     pa_cvolume soft_volume;      /* The internal software volume we apply to all PCM data while it passes through */
  95
  96     bool muted:1;
  97
  98     bool refresh_volume:1;
  99     bool refresh_muted:1;
 100     bool save_port:1;
 101     bool save_volume:1;
 102     bool save_muted:1;
 103
 104     /* Saved volume state while we're in passthrough mode */
 105     pa_cvolume saved_volume;
 106     bool saved_save_volume:1;
 107
 108     pa_asyncmsgq *asyncmsgq;
 109
 110     pa_memchunk silence;
 111
 112     pa_hashmap *ports;
 113     pa_device_port *active_port;
 114     pa_atomic_t mixer_dirty;
 115
 116     /* The latency offset is inherited from the currently active port */
 117     int64_t latency_offset;
 118
 119     unsigned priority;
 120
 121     bool set_mute_in_progress;
 122
 123     /* Called when the main loop requests a state change. Called from
 124      * main loop context. If returns -1 the state change will be
 125      * inhibited */
 126     int (*set_state)(pa_sink *s, pa_sink_state_t state); /* may be NULL */
 127
 128     /* Sink drivers that support hardware volume may set this
 129      * callback. This is called when the current volume needs to be
 130      * re-read from the hardware.
 131      *
 132      * There are two ways for drivers to implement hardware volume
 133      * query: either set this callback or handle
 134      * PA_SINK_MESSAGE_GET_VOLUME. The callback implementation or the
 135      * message handler must update s->real_volume and s->soft_volume
 136      * (using pa_sink_set_soft_volume()) to match the current hardware
 137      * volume.
 138      *
 139      * If PA_SINK_DEFERRED_VOLUME is not set, then this is called from the
 140      * main thread before sending PA_SINK_MESSAGE_GET_VOLUME, so in
 141      * this case the driver can choose whether to read the volume from
 142      * the hardware in the main thread or in the IO thread.
 143      *
 144      * If PA_SINK_DEFERRED_VOLUME is set, then this is called from the IO
 145      * thread within the default handler for
 146      * PA_SINK_MESSAGE_GET_VOLUME (the main thread is waiting while
 147      * the message is being processed), so there's no choice of where
 148      * to do the volume reading - it has to be done in the IO thread
 149      * always.
 150      *
 151      * You must use the function pa_sink_set_get_volume_callback() to
 152      * set this callback. */
 153     pa_sink_cb_t get_volume; /* may be NULL */
 154
 155     /* Sink drivers that support hardware volume must set this
 156      * callback. This is called when the hardware volume needs to be
 157      * updated.
 158      *
 159      * If PA_SINK_DEFERRED_VOLUME is not set, then this is called from the
 160      * main thread. The callback implementation must set the hardware
 161      * volume according to s->real_volume. If the driver can't set the
 162      * hardware volume to the exact requested value, it has to update
 163      * s->real_volume and/or s->soft_volume so that they together
 164      * match the actual hardware volume that was set.
 165      *
 166      * If PA_SINK_DEFERRED_VOLUME is set, then this is called from the IO
 167      * thread. The callback implementation must not actually set the
 168      * hardware volume yet, but it must check how close to the
 169      * requested volume the hardware volume can be set, and update
 170      * s->real_volume and/or s->soft_volume so that they together
 171      * match the actual hardware volume that will be set later in the
 172      * write_volume callback.
 173      *
 174      * You must use the function pa_sink_set_set_volume_callback() to
 175      * set this callback. */
 176     pa_sink_cb_t set_volume; /* may be NULL */
 177
 178     /* Sink drivers that set PA_SINK_DEFERRED_VOLUME must provide this
 179      * callback. This callback is not used with sinks that do not set
 180      * PA_SINK_DEFERRED_VOLUME. This is called from the IO thread when a
 181      * pending hardware volume change has to be written to the
 182      * hardware. The requested volume is passed to the callback
 183      * implementation in s->thread_info.current_hw_volume.
 184      *
 185      * The call is done inside pa_sink_volume_change_apply(), which is
 186      * not called automatically - it is the driver's responsibility to
 187      * schedule that function to be called at the right times in the
 188      * IO thread.
 189      *
 190      * You must use the function pa_sink_set_write_volume_callback() to
 191      * set this callback. */
 192     pa_sink_cb_t write_volume; /* may be NULL */
 193
 194     /* Called when the mute setting is queried. A PA_SINK_MESSAGE_GET_MUTE
 195      * message will also be sent. Called from IO thread if PA_SINK_DEFERRED_VOLUME
 196      * flag is set otherwise from main loop context. If refresh_mute is false
 197      * neither this function is called nor a message is sent.
 198      *
 199      * You must use the function pa_sink_set_get_mute_callback() to
 200      * set this callback. */
 201     pa_sink_cb_t get_mute; /* may be NULL */
 202
 203     /* Called when the mute setting shall be changed. A PA_SINK_MESSAGE_SET_MUTE
 204      * message will also be sent. Called from IO thread if PA_SINK_DEFERRED_VOLUME
 205      * flag is set otherwise from main loop context.
 206      *
 207      * You must use the function pa_sink_set_set_mute_callback() to
 208      * set this callback. */
 209     pa_sink_cb_t set_mute; /* may be NULL */
 210
 211     /* Called when a rewind request is issued. Called from IO thread
 212      * context. */
 213     pa_sink_cb_t request_rewind; /* may be NULL */
 214
 215     /* Called when a the requested latency is changed. Called from IO
 216      * thread context. */
 217     pa_sink_cb_t update_requested_latency; /* may be NULL */
 218
 219     /* Called whenever the port shall be changed. Called from IO
 220      * thread if deferred volumes are enabled, and main thread otherwise. */
 221     int (*set_port)(pa_sink *s, pa_device_port *port); /* may be NULL */
 222
 223     /* Called to get the list of formats supported by the sink, sorted
 224      * in descending order of preference. */
 225     pa_idxset* (*get_formats)(pa_sink *s); /* may be NULL */
 226
 227     /* Called to set the list of formats supported by the sink. Can be
 228      * NULL if the sink does not support this. Returns true on success,
 229      * false otherwise (for example when an unsupportable format is
 230      * set). Makes a copy of the formats passed in. */
 231     bool (*set_formats)(pa_sink *s, pa_idxset *formats); /* may be NULL */
 232
 233     /* Called whenever the sampling frequency shall be changed. Called from
 234      * main thread. */
 235     int (*update_rate)(pa_sink *s, uint32_t rate);
 236
 237     /* Contains copies of the above data so that the real-time worker
 238      * thread can work without access locking */
 239     struct {
 240         pa_sink_state_t state;
 241         pa_hashmap *inputs;
 242
 243         pa_rtpoll *rtpoll;
 244
 245         pa_cvolume soft_volume;
 246         bool soft_muted:1;
 247
 248         /* The requested latency is used for dynamic latency
 249          * sinks. For fixed latency sinks it is always identical to
 250          * the fixed_latency. See below. */
 251         bool requested_latency_valid:1;
 252         pa_usec_t requested_latency;
 253
 254         /* The number of bytes streams need to keep around as history to
 255          * be able to satisfy every DMA buffer rewrite */
 256         size_t max_rewind;
 257
 258         /* The number of bytes streams need to keep around to satisfy
 259          * every DMA write request */
 260         size_t max_request;
 261
 262         /* Maximum of what clients requested to rewind in this cycle */
 263         size_t rewind_nbytes;
 264         bool rewind_requested;
 265
 266         /* Both dynamic and fixed latencies will be clamped to this
 267          * range. */
 268         pa_usec_t min_latency; /* we won't go below this latency */
 269         pa_usec_t max_latency; /* An upper limit for the latencies */
 270
 271         /* 'Fixed' simply means that the latency is exclusively
 272          * decided on by the sink, and the clients have no influence
 273          * in changing it */
 274         pa_usec_t fixed_latency; /* for sinks with PA_SINK_DYNAMIC_LATENCY this is 0 */
 275
 276         /* This latency offset is a direct copy from s->latency_offset */
 277         int64_t latency_offset;
 278
 279         /* Delayed volume change events are queued here. The events
 280          * are stored in expiration order. The one expiring next is in
 281          * the head of the list. */
 282         PA_LLIST_HEAD(pa_sink_volume_change, volume_changes);
 283         pa_sink_volume_change *volume_changes_tail;
 284         /* This value is updated in pa_sink_volume_change_apply() and
 285          * used only by sinks with PA_SINK_DEFERRED_VOLUME. */
 286         pa_cvolume current_hw_volume;
 287
 288         /* The amount of usec volume up events are delayed and volume
 289          * down events are made earlier. */
 290         uint32_t volume_change_safety_margin;
 291         /* Usec delay added to all volume change events, may be negative. */
 292         int32_t volume_change_extra_delay;
 293     } thread_info;
 294
 295     void *userdata;
 296 };
 297
 298 PA_DECLARE_PUBLIC_CLASS(pa_sink);
 299 #define PA_SINK(s) (pa_sink_cast(s))
 300
 301 typedef enum pa_sink_message {
 302     PA_SINK_MESSAGE_ADD_INPUT,
 303     PA_SINK_MESSAGE_REMOVE_INPUT,
 304     PA_SINK_MESSAGE_GET_VOLUME,
 305     PA_SINK_MESSAGE_SET_SHARED_VOLUME,
 306     PA_SINK_MESSAGE_SET_VOLUME_SYNCED,
 307     PA_SINK_MESSAGE_SET_VOLUME,
 308     PA_SINK_MESSAGE_SYNC_VOLUMES,
 309     PA_SINK_MESSAGE_GET_MUTE,
 310     PA_SINK_MESSAGE_SET_MUTE,
 311     PA_SINK_MESSAGE_GET_LATENCY,
 312     PA_SINK_MESSAGE_GET_REQUESTED_LATENCY,
 313     PA_SINK_MESSAGE_SET_STATE,
 314     PA_SINK_MESSAGE_START_MOVE,
 315     PA_SINK_MESSAGE_FINISH_MOVE,
 316     PA_SINK_MESSAGE_SET_LATENCY_RANGE,
 317     PA_SINK_MESSAGE_GET_LATENCY_RANGE,
 318     PA_SINK_MESSAGE_SET_FIXED_LATENCY,
 319     PA_SINK_MESSAGE_GET_FIXED_LATENCY,
 320     PA_SINK_MESSAGE_GET_MAX_REWIND,
 321     PA_SINK_MESSAGE_GET_MAX_REQUEST,
 322     PA_SINK_MESSAGE_SET_MAX_REWIND,
 323     PA_SINK_MESSAGE_SET_MAX_REQUEST,
 324     PA_SINK_MESSAGE_SET_PORT,
 325     PA_SINK_MESSAGE_UPDATE_VOLUME_AND_MUTE,
 326     PA_SINK_MESSAGE_SET_LATENCY_OFFSET,
 327     PA_SINK_MESSAGE_MAX
 328 } pa_sink_message_t;
 329
 330 typedef struct pa_sink_new_data {
 331     pa_suspend_cause_t suspend_cause;
 332
 333     char *name;
 334     pa_proplist *proplist;
 335
 336     const char *driver;
 337     pa_module *module;
 338     pa_card *card;
 339
 340     pa_hashmap *ports;
 341     char *active_port;
 342
 343     pa_sample_spec sample_spec;
 344     pa_channel_map channel_map;
 345     uint32_t alternate_sample_rate;
 346     pa_cvolume volume;
 347     bool muted :1;
 348
 349     bool sample_spec_is_set:1;
 350     bool channel_map_is_set:1;
 351     bool alternate_sample_rate_is_set:1;
 352     bool volume_is_set:1;
 353     bool muted_is_set:1;
 354
 355     bool namereg_fail:1;
 356
 357     bool save_port:1;
 358     bool save_volume:1;
 359     bool save_muted:1;
 360 } pa_sink_new_data;
 361
 362 pa_sink_new_data* pa_sink_new_data_init(pa_sink_new_data *data);
 363 void pa_sink_new_data_set_name(pa_sink_new_data *data, const char *name);
 364 void pa_sink_new_data_set_sample_spec(pa_sink_new_data *data, const pa_sample_spec *spec);
 365 void pa_sink_new_data_set_channel_map(pa_sink_new_data *data, const pa_channel_map *map);
 366 void pa_sink_new_data_set_alternate_sample_rate(pa_sink_new_data *data, const uint32_t alternate_sample_rate);
 367 void pa_sink_new_data_set_volume(pa_sink_new_data *data, const pa_cvolume *volume);
 368 void pa_sink_new_data_set_muted(pa_sink_new_data *data, bool mute);
 369 void pa_sink_new_data_set_port(pa_sink_new_data *data, const char *port);
 370 void pa_sink_new_data_done(pa_sink_new_data *data);
 371
 372 /*** To be called exclusively by the sink driver, from main context */
 373
 374 pa_sink* pa_sink_new(
 375         pa_core *core,
 376         pa_sink_new_data *data,
 377         pa_sink_flags_t flags);
 378
 379 void pa_sink_set_get_volume_callback(pa_sink *s, pa_sink_cb_t cb);
 380 void pa_sink_set_set_volume_callback(pa_sink *s, pa_sink_cb_t cb);
 381 void pa_sink_set_write_volume_callback(pa_sink *s, pa_sink_cb_t cb);
 382 void pa_sink_set_get_mute_callback(pa_sink *s, pa_sink_cb_t cb);
 383 void pa_sink_set_set_mute_callback(pa_sink *s, pa_sink_cb_t cb);
 384 void pa_sink_enable_decibel_volume(pa_sink *s, bool enable);
 385
 386 void pa_sink_put(pa_sink *s);
 387 void pa_sink_unlink(pa_sink* s);
 388
 389 void pa_sink_set_description(pa_sink *s, const char *description);
 390 void pa_sink_set_asyncmsgq(pa_sink *s, pa_asyncmsgq *q);
 391 void pa_sink_set_rtpoll(pa_sink *s, pa_rtpoll *p);
 392
 393 void pa_sink_set_max_rewind(pa_sink *s, size_t max_rewind);
 394 void pa_sink_set_max_request(pa_sink *s, size_t max_request);
 395 void pa_sink_set_latency_range(pa_sink *s, pa_usec_t min_latency, pa_usec_t max_latency);
 396 void pa_sink_set_fixed_latency(pa_sink *s, pa_usec_t latency);
 397
 398 void pa_sink_set_soft_volume(pa_sink *s, const pa_cvolume *volume);
 399 void pa_sink_volume_changed(pa_sink *s, const pa_cvolume *new_volume);
 400 void pa_sink_mute_changed(pa_sink *s, bool new_muted);
 401
 402 void pa_sink_update_flags(pa_sink *s, pa_sink_flags_t mask, pa_sink_flags_t value);
 403
 404 bool pa_device_init_description(pa_proplist *p, pa_card *card);
 405 bool pa_device_init_icon(pa_proplist *p, bool is_sink);
 406 bool pa_device_init_intended_roles(pa_proplist *p);
 407 unsigned pa_device_init_priority(pa_proplist *p);
 408
 409 /**** May be called by everyone, from main context */
 410
 411 int pa_sink_update_rate(pa_sink *s, uint32_t rate, bool passthrough);
 412 void pa_sink_set_latency_offset(pa_sink *s, int64_t offset);
 413
 414 /* The returned value is supposed to be in the time domain of the sound card! */
 415 pa_usec_t pa_sink_get_latency(pa_sink *s);
 416 pa_usec_t pa_sink_get_requested_latency(pa_sink *s);
 417 void pa_sink_get_latency_range(pa_sink *s, pa_usec_t *min_latency, pa_usec_t *max_latency);
 418 pa_usec_t pa_sink_get_fixed_latency(pa_sink *s);
 419
 420 size_t pa_sink_get_max_rewind(pa_sink *s);
 421 size_t pa_sink_get_max_request(pa_sink *s);
 422
 423 int pa_sink_update_status(pa_sink*s);
 424 int pa_sink_suspend(pa_sink *s, bool suspend, pa_suspend_cause_t cause);
 425 int pa_sink_suspend_all(pa_core *c, bool suspend, pa_suspend_cause_t cause);
 426
 427 /* Use this instead of checking s->flags & PA_SINK_FLAT_VOLUME directly. */
 428 bool pa_sink_flat_volume_enabled(pa_sink *s);
 429
 430 /* Get the master sink when sharing volumes */
 431 pa_sink *pa_sink_get_master(pa_sink *s);
 432
 433 /* Is the sink in passthrough mode? (that is, is there a passthrough sink input
 434  * connected to this sink? */
 435 bool pa_sink_is_passthrough(pa_sink *s);
 436 /* These should be called when a sink enters/leaves passthrough mode */
 437 void pa_sink_enter_passthrough(pa_sink *s);
 438 void pa_sink_leave_passthrough(pa_sink *s);
 439
 440 void pa_sink_set_volume(pa_sink *sink, const pa_cvolume *volume, bool sendmsg, bool save);
 441 const pa_cvolume *pa_sink_get_volume(pa_sink *sink, bool force_refresh);
 442
 443 void pa_sink_set_mute(pa_sink *sink, bool mute, bool save);
 444 bool pa_sink_get_mute(pa_sink *sink, bool force_refresh);
 445
 446 bool pa_sink_update_proplist(pa_sink *s, pa_update_mode_t mode, pa_proplist *p);
 447
 448 int pa_sink_set_port(pa_sink *s, const char *name, bool save);
 449 void pa_sink_set_mixer_dirty(pa_sink *s, bool is_dirty);
 450
 451 unsigned pa_sink_linked_by(pa_sink *s); /* Number of connected streams */
 452 unsigned pa_sink_used_by(pa_sink *s); /* Number of connected streams which are not corked */
 453 unsigned pa_sink_check_suspend(pa_sink *s); /* Returns how many streams are active that don't allow suspensions */
 454 #define pa_sink_get_state(s) ((s)->state)
 455
 456 /* Moves all inputs away, and stores them in pa_queue */
 457 pa_queue *pa_sink_move_all_start(pa_sink *s, pa_queue *q);
 458 void pa_sink_move_all_finish(pa_sink *s, pa_queue *q, bool save);
 459 void pa_sink_move_all_fail(pa_queue *q);
 460
 461 /* Returns a copy of the sink formats. TODO: Get rid of this function (or at
 462  * least get rid of the copying). There's no good reason to copy the formats
 463  * every time someone wants to know what formats the sink supports. The formats
 464  * idxset could be stored directly in the pa_sink struct.
 465  * https://bugs.freedesktop.org/show_bug.cgi?id=71924 */
 466 pa_idxset* pa_sink_get_formats(pa_sink *s);
 467
 468 bool pa_sink_set_formats(pa_sink *s, pa_idxset *formats);
 469 bool pa_sink_check_format(pa_sink *s, pa_format_info *f);
 470 pa_idxset* pa_sink_check_formats(pa_sink *s, pa_idxset *in_formats);
 471
 472 /*** To be called exclusively by the sink driver, from IO context */
 473
 474 void pa_sink_render(pa_sink*s, size_t length, pa_memchunk *result);
 475 void pa_sink_render_full(pa_sink *s, size_t length, pa_memchunk *result);
 476 void pa_sink_render_into(pa_sink*s, pa_memchunk *target);
 477 void pa_sink_render_into_full(pa_sink *s, pa_memchunk *target);
 478
 479 void pa_sink_process_rewind(pa_sink *s, size_t nbytes);
 480
 481 int pa_sink_process_msg(pa_msgobject *o, int code, void *userdata, int64_t offset, pa_memchunk *chunk);
 482
 483 void pa_sink_attach_within_thread(pa_sink *s);
 484 void pa_sink_detach_within_thread(pa_sink *s);
 485
 486 pa_usec_t pa_sink_get_requested_latency_within_thread(pa_sink *s);
 487
 488 void pa_sink_set_max_rewind_within_thread(pa_sink *s, size_t max_rewind);
 489 void pa_sink_set_max_request_within_thread(pa_sink *s, size_t max_request);
 490
 491 void pa_sink_set_latency_range_within_thread(pa_sink *s, pa_usec_t min_latency, pa_usec_t max_latency);
 492 void pa_sink_set_fixed_latency_within_thread(pa_sink *s, pa_usec_t latency);
 493
 494 void pa_sink_update_volume_and_mute(pa_sink *s);
 495
 496 bool pa_sink_volume_change_apply(pa_sink *s, pa_usec_t *usec_to_next);
 497
 498 size_t pa_sink_process_input_underruns(pa_sink *s, size_t left_to_play);
 499
 500 /*** To be called exclusively by sink input drivers, from IO context */
 501
 502 void pa_sink_request_rewind(pa_sink*s, size_t nbytes);
 503
 504 void pa_sink_invalidate_requested_latency(pa_sink *s, bool dynamic);
 505
 506 pa_usec_t pa_sink_get_latency_within_thread(pa_sink *s);
 507
 508 /* Called from the main thread, from sink-input.c only. The normal way to set
 509  * the sink reference volume is to call pa_sink_set_volume(), but the flat
 510  * volume logic in sink-input.c needs also a function that doesn't do all the
 511  * extra stuff that pa_sink_set_volume() does. This function simply sets
 512  * s->reference_volume and fires change notifications. */
 513 void pa_sink_set_reference_volume_direct(pa_sink *s, const pa_cvolume *volume);
 514
 515 /* Verify that we called in IO context (aka 'thread context), or that
 516  * the sink is not yet set up, i.e. the thread not set up yet. See
 517  * pa_assert_io_context() in thread-mq.h for more information. */
 518 #define pa_sink_assert_io_context(s) \
 519     pa_assert(pa_thread_mq_get() || !PA_SINK_IS_LINKED((s)->state))
 520
 521 #endif