summaryrefslogtreecommitdiff
path: root/backends/pulse/pulse-stream-control.c
blob: 5ed5bb8f1b16e567bd7a3142c03b2254f249d441 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
/*
 * Copyright (C) 2014 Michal Ratajsky <michal.ratajsky@gmail.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the licence, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
 */

#include <glib.h>
#include <glib-object.h>
#include <libmatemixer/matemixer.h>
#include <libmatemixer/matemixer-private.h>

#include <pulse/pulseaudio.h>

#include "pulse-connection.h"
#include "pulse-helpers.h"
#include "pulse-monitor.h"
#include "pulse-stream.h"
#include "pulse-stream-control.h"

struct _PulseStreamControlPrivate
{
    guint32           index;
    guint             volume;
    pa_cvolume        cvolume;
    pa_volume_t       base_volume;
    pa_channel_map    channel_map;
    PulseConnection  *connection;
    PulseMonitor     *monitor;
    MateMixerAppInfo *app_info;
};

enum {
    PROP_0,
    PROP_INDEX,
    PROP_CONNECTION,
    N_PROPERTIES
};

static GParamSpec *properties[N_PROPERTIES] = { NULL, };

static void pulse_stream_control_class_init   (PulseStreamControlClass *klass);

static void pulse_stream_control_get_property (GObject                 *object,
                                               guint                    param_id,
                                               GValue                  *value,
                                               GParamSpec              *pspec);
static void pulse_stream_control_set_property (GObject                 *object,
                                               guint                    param_id,
                                               const GValue            *value,
                                               GParamSpec              *pspec);

static void pulse_stream_control_init         (PulseStreamControl      *control);
static void pulse_stream_control_dispose      (GObject                 *object);
static void pulse_stream_control_finalize     (GObject                 *object);

G_DEFINE_ABSTRACT_TYPE (PulseStreamControl, pulse_stream_control, MATE_MIXER_TYPE_STREAM_CONTROL)

static MateMixerAppInfo *       pulse_stream_control_get_app_info         (MateMixerStreamControl   *mmsc);

static gboolean                 pulse_stream_control_set_mute             (MateMixerStreamControl   *mmsc,
                                                                           gboolean                  mute);

static guint                    pulse_stream_control_get_num_channels     (MateMixerStreamControl   *mmsc);

static guint                    pulse_stream_control_get_volume           (MateMixerStreamControl   *mmsc);
static gboolean                 pulse_stream_control_set_volume           (MateMixerStreamControl   *mmsc,
                                                                           guint                     volume);

static gdouble                  pulse_stream_control_get_decibel          (MateMixerStreamControl   *mmsc);
static gboolean                 pulse_stream_control_set_decibel          (MateMixerStreamControl   *mmsc,
                                                                           gdouble                   decibel);

static guint                    pulse_stream_control_get_channel_volume   (MateMixerStreamControl   *mmsc,
                                                                           guint                     channel);
static gboolean                 pulse_stream_control_set_channel_volume   (MateMixerStreamControl   *mmsc,
                                                                           guint                     channel,
                                                                           guint                     volume);

static gdouble                  pulse_stream_control_get_channel_decibel  (MateMixerStreamControl   *mmsc,
                                                                           guint                     channel);
static gboolean                 pulse_stream_control_set_channel_decibel  (MateMixerStreamControl   *mmsc,
                                                                           guint                     channel,
                                                                           gdouble                   decibel);

static MateMixerChannelPosition pulse_stream_control_get_channel_position (MateMixerStreamControl   *mmsc,
                                                                           guint                     channel);
static gboolean                 pulse_stream_control_has_channel_position (MateMixerStreamControl   *mmsc,
                                                                           MateMixerChannelPosition  position);

static gboolean                 pulse_stream_control_set_balance          (MateMixerStreamControl   *mmsc,
                                                                           gfloat                    balance);

static gboolean                 pulse_stream_control_set_fade             (MateMixerStreamControl   *mmsc,
                                                                           gfloat                    fade);

static gboolean                 pulse_stream_control_get_monitor_enabled  (MateMixerStreamControl   *mmsc);
static gboolean                 pulse_stream_control_set_monitor_enabled  (MateMixerStreamControl   *mmsc,
                                                                           gboolean                  enabled);

static guint                    pulse_stream_control_get_min_volume       (MateMixerStreamControl   *mmsc);
static guint                    pulse_stream_control_get_max_volume       (MateMixerStreamControl   *mmsc);
static guint                    pulse_stream_control_get_normal_volume    (MateMixerStreamControl   *mmsc);
static guint                    pulse_stream_control_get_base_volume      (MateMixerStreamControl   *mmsc);

static void                     on_monitor_value (PulseMonitor       *monitor,
                                                  gdouble             value,
                                                  PulseStreamControl *control);

static void                     set_balance_fade (PulseStreamControl *control);

static gboolean                 set_cvolume      (PulseStreamControl *control,
                                                  pa_cvolume         *cvolume);

static void
pulse_stream_control_class_init (PulseStreamControlClass *klass)
{
    GObjectClass                *object_class;
    MateMixerStreamControlClass *control_class;

    object_class = G_OBJECT_CLASS (klass);
    object_class->dispose      = pulse_stream_control_dispose;
    object_class->finalize     = pulse_stream_control_finalize;
    object_class->get_property = pulse_stream_control_get_property;
    object_class->set_property = pulse_stream_control_set_property;

    control_class = MATE_MIXER_STREAM_CONTROL_CLASS (klass);
    control_class->get_app_info         = pulse_stream_control_get_app_info;
    control_class->set_mute             = pulse_stream_control_set_mute;
    control_class->get_num_channels     = pulse_stream_control_get_num_channels;
    control_class->get_volume           = pulse_stream_control_get_volume;
    control_class->set_volume           = pulse_stream_control_set_volume;
    control_class->get_decibel          = pulse_stream_control_get_decibel;
    control_class->set_decibel          = pulse_stream_control_set_decibel;
    control_class->get_channel_volume   = pulse_stream_control_get_channel_volume;
    control_class->set_channel_volume   = pulse_stream_control_set_channel_volume;
    control_class->get_channel_decibel  = pulse_stream_control_get_channel_decibel;
    control_class->set_channel_decibel  = pulse_stream_control_set_channel_decibel;
    control_class->get_channel_position = pulse_stream_control_get_channel_position;
    control_class->has_channel_position = pulse_stream_control_has_channel_position;
    control_class->set_balance          = pulse_stream_control_set_balance;
    control_class->set_fade             = pulse_stream_control_set_fade;
    control_class->get_monitor_enabled  = pulse_stream_control_get_monitor_enabled;
    control_class->set_monitor_enabled  = pulse_stream_control_set_monitor_enabled;
    control_class->get_min_volume       = pulse_stream_control_get_min_volume;
    control_class->get_max_volume       = pulse_stream_control_get_max_volume;
    control_class->get_normal_volume    = pulse_stream_control_get_normal_volume;
    control_class->get_base_volume      = pulse_stream_control_get_base_volume;

    properties[PROP_INDEX] =
        g_param_spec_uint ("index",
                           "Index",
                           "Index of the stream control",
                           0,
                           G_MAXUINT,
                           0,
                           G_PARAM_READWRITE |
                           G_PARAM_CONSTRUCT_ONLY |
                           G_PARAM_STATIC_STRINGS);

    properties[PROP_CONNECTION] =
        g_param_spec_object ("connection",
                             "Connection",
                             "PulseAudio connection",
                             PULSE_TYPE_CONNECTION,
                             G_PARAM_READWRITE |
                             G_PARAM_CONSTRUCT_ONLY |
                             G_PARAM_STATIC_STRINGS);

    g_object_class_install_properties (object_class, N_PROPERTIES, properties);

    g_type_class_add_private (object_class, sizeof (PulseStreamControlPrivate));
}

static void
pulse_stream_control_get_property (GObject    *object,
                                   guint       param_id,
                                   GValue     *value,
                                   GParamSpec *pspec)
{
    PulseStreamControl *control;

    control = PULSE_STREAM_CONTROL (object);

    switch (param_id) {
    case PROP_INDEX:
        g_value_set_uint (value, control->priv->index);
        break;
    case PROP_CONNECTION:
        g_value_set_object (value, control->priv->connection);
        break;
    default:
        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, param_id, pspec);
        break;
    }
}

static void
pulse_stream_control_set_property (GObject      *object,
                                   guint         param_id,
                                   const GValue *value,
                                   GParamSpec   *pspec)
{
    PulseStreamControl *control;

    control = PULSE_STREAM_CONTROL (object);

    switch (param_id) {
    case PROP_INDEX:
        control->priv->index = g_value_get_uint (value);
        break;
    case PROP_CONNECTION:
        control->priv->connection = g_value_dup_object (value);
        break;
    default:
        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, param_id, pspec);
        break;
    }
}

static void
pulse_stream_control_init (PulseStreamControl *control)
{
    control->priv = G_TYPE_INSTANCE_GET_PRIVATE (control,
                                                 PULSE_TYPE_STREAM_CONTROL,
                                                 PulseStreamControlPrivate);

    /* Initialize empty volume and channel map structures, they will be used
     * if the stream does not support volume */
    pa_cvolume_init (&control->priv->cvolume);

    pa_channel_map_init (&control->priv->channel_map);
}

static void
pulse_stream_control_dispose (GObject *object)
{
    PulseStreamControl *control;

    control = PULSE_STREAM_CONTROL (object);

    g_clear_object (&control->priv->monitor);
    g_clear_object (&control->priv->connection);

    G_OBJECT_CLASS (pulse_stream_control_parent_class)->dispose (object);
}

static void
pulse_stream_control_finalize (GObject *object)
{
    PulseStreamControl *control;

    control = PULSE_STREAM_CONTROL (object);

    if (control->priv->app_info != NULL)
        _mate_mixer_app_info_free (control->priv->app_info);

    G_OBJECT_CLASS (pulse_stream_control_parent_class)->finalize (object);
}

guint32
pulse_stream_control_get_index (PulseStreamControl *control)
{
    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (control), PA_INVALID_INDEX);

    return control->priv->index;
}

guint32
pulse_stream_control_get_stream_index (PulseStreamControl *control)
{
    MateMixerStream *stream;

    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (control), PA_INVALID_INDEX);

    stream = mate_mixer_stream_control_get_stream (MATE_MIXER_STREAM_CONTROL (control));
    if G_UNLIKELY (stream == NULL)
        return PA_INVALID_INDEX;

    return pulse_stream_get_index (PULSE_STREAM (stream));
}

PulseConnection *
pulse_stream_control_get_connection (PulseStreamControl *control)
{
    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (control), NULL);

    return control->priv->connection;
}

PulseMonitor *
pulse_stream_control_get_monitor (PulseStreamControl *control)
{
    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (control), NULL);

    return control->priv->monitor;
}

const pa_cvolume *
pulse_stream_control_get_cvolume (PulseStreamControl *control)
{
    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (control), NULL);

    return &control->priv->cvolume;
}

const pa_channel_map *
pulse_stream_control_get_channel_map (PulseStreamControl *control)
{
    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (control), NULL);

    return &control->priv->channel_map;
}

void
pulse_stream_control_set_app_info (PulseStreamControl *control,
                                   MateMixerAppInfo   *info,
                                   gboolean            take)
{
    g_return_if_fail (PULSE_IS_STREAM_CONTROL (control));

    if G_UNLIKELY (control->priv->app_info != NULL)
        _mate_mixer_app_info_free (control->priv->app_info);

    if (take == TRUE)
        control->priv->app_info = info;
    else
        control->priv->app_info = _mate_mixer_app_info_copy (info);
}

void
pulse_stream_control_set_channel_map (PulseStreamControl *control, const pa_channel_map *map)
{
    MateMixerStreamControlFlags flags;

    g_return_if_fail (PULSE_IS_STREAM_CONTROL (control));

    flags = mate_mixer_stream_control_get_flags (MATE_MIXER_STREAM_CONTROL (control));

    if (map != NULL && pa_channel_map_valid (map)) {
        if (pa_channel_map_can_balance (map))
            flags |= MATE_MIXER_STREAM_CONTROL_CAN_BALANCE;
        else
            flags &= ~MATE_MIXER_STREAM_CONTROL_CAN_BALANCE;

        if (pa_channel_map_can_fade (map))
            flags |= MATE_MIXER_STREAM_CONTROL_CAN_FADE;
        else
            flags &= ~MATE_MIXER_STREAM_CONTROL_CAN_FADE;

        control->priv->channel_map = *map;
    } else {
        flags &= ~(MATE_MIXER_STREAM_CONTROL_CAN_BALANCE | MATE_MIXER_STREAM_CONTROL_CAN_FADE);

        /* If the channel map is not valid, create an empty channel map, which
         * also won't validate, but at least we know what it is */
        pa_channel_map_init (&control->priv->channel_map);
    }

    _mate_mixer_stream_control_set_flags (MATE_MIXER_STREAM_CONTROL (control), flags);
}

void
pulse_stream_control_set_cvolume (PulseStreamControl *control,
                                  const pa_cvolume   *cvolume,
                                  pa_volume_t         base_volume)
{
    MateMixerStreamControlFlags flags;

    g_return_if_fail (PULSE_IS_STREAM_CONTROL (control));

    /* The base volume is not a property */
    control->priv->base_volume = base_volume;

    flags = mate_mixer_stream_control_get_flags (MATE_MIXER_STREAM_CONTROL (control));

    g_object_freeze_notify (G_OBJECT (control));

    if (cvolume != NULL && pa_cvolume_valid (cvolume)) {
        /* Decibel volume and volume settability flags must be provided by
         * the implementation */
        flags |= MATE_MIXER_STREAM_CONTROL_VOLUME_READABLE;

        if (pa_cvolume_equal (&control->priv->cvolume, cvolume) == 0) {
            control->priv->cvolume = *cvolume;
            control->priv->volume  = (guint) pa_cvolume_max (&control->priv->cvolume);

            g_object_notify (G_OBJECT (control), "volume");
        }
    } else {
        flags &= ~(MATE_MIXER_STREAM_CONTROL_VOLUME_READABLE |
                   MATE_MIXER_STREAM_CONTROL_VOLUME_WRITABLE |
                   MATE_MIXER_STREAM_CONTROL_HAS_DECIBEL);

        /* If the cvolume is not valid, create an empty cvolume, which also
         * won't validate, but at least we know what it is */
        pa_cvolume_init (&control->priv->cvolume);

        if (control->priv->volume != (guint) PA_VOLUME_MUTED) {
            control->priv->volume = (guint) PA_VOLUME_MUTED;

            g_object_notify (G_OBJECT (control), "volume");
        }
    }

    _mate_mixer_stream_control_set_flags (MATE_MIXER_STREAM_CONTROL (control), flags);

    /* Changing volume may change the balance and fade values as well */
    set_balance_fade (control);

    g_object_thaw_notify (G_OBJECT (control));
}

static MateMixerAppInfo *
pulse_stream_control_get_app_info (MateMixerStreamControl *mmsc)
{
    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), NULL);

    return PULSE_STREAM_CONTROL (mmsc)->priv->app_info;
}

static gboolean
pulse_stream_control_set_mute (MateMixerStreamControl *mmsc, gboolean mute)
{
    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), FALSE);

    return PULSE_STREAM_CONTROL_GET_CLASS (mmsc)->set_mute (PULSE_STREAM_CONTROL (mmsc), mute);
}

static guint
pulse_stream_control_get_num_channels (MateMixerStreamControl *mmsc)
{
    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), 0);

    return PULSE_STREAM_CONTROL (mmsc)->priv->channel_map.channels;
}

static guint
pulse_stream_control_get_volume (MateMixerStreamControl *mmsc)
{
    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), (guint) PA_VOLUME_MUTED);

    return PULSE_STREAM_CONTROL (mmsc)->priv->volume;
}

static gboolean
pulse_stream_control_set_volume (MateMixerStreamControl *mmsc, guint volume)
{
    PulseStreamControl *control;
    pa_cvolume          cvolume;

    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), FALSE);

    control = PULSE_STREAM_CONTROL (mmsc);
    cvolume = control->priv->cvolume;

    if (pa_cvolume_scale (&cvolume, (pa_volume_t) volume) == NULL)
        return FALSE;

    return set_cvolume (control, &cvolume);
}

static gdouble
pulse_stream_control_get_decibel (MateMixerStreamControl *mmsc)
{
    gdouble value;

    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), -MATE_MIXER_INFINITY);

    value = pa_sw_volume_to_dB (pulse_stream_control_get_volume (mmsc));

    /* PA_VOLUME_MUTED is converted to PA_DECIBEL_MININFTY */
    return (value == PA_DECIBEL_MININFTY) ? -MATE_MIXER_INFINITY : value;
}

static gboolean
pulse_stream_control_set_decibel (MateMixerStreamControl *mmsc, gdouble decibel)
{
    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), FALSE);

    return pulse_stream_control_set_volume (mmsc,
                                            pa_sw_volume_from_dB (decibel));
}

static guint
pulse_stream_control_get_channel_volume (MateMixerStreamControl *mmsc, guint channel)
{
    PulseStreamControl *control;

    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), (guint) PA_VOLUME_MUTED);

    control = PULSE_STREAM_CONTROL (mmsc);

    if (channel >= control->priv->cvolume.channels)
        return (guint) PA_VOLUME_MUTED;

    return (guint) control->priv->cvolume.values[channel];
}

static gboolean
pulse_stream_control_set_channel_volume (MateMixerStreamControl *mmsc, guint channel, guint volume)
{
    PulseStreamControl *control;
    pa_cvolume          cvolume;

    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), FALSE);

    control = PULSE_STREAM_CONTROL (mmsc);

    if (channel >= control->priv->cvolume.channels)
        return FALSE;

    /* This is safe, because the cvolume is validated by set_cvolume() */
    cvolume = control->priv->cvolume;
    cvolume.values[channel] = (pa_volume_t) volume;

    return set_cvolume (control, &cvolume);
}

static gdouble
pulse_stream_control_get_channel_decibel (MateMixerStreamControl *mmsc, guint channel)
{
    PulseStreamControl *control;
    gdouble             value;

    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), -MATE_MIXER_INFINITY);

    control = PULSE_STREAM_CONTROL (mmsc);

    if (channel >= control->priv->cvolume.channels)
        return -MATE_MIXER_INFINITY;

    value = pa_sw_volume_to_dB (control->priv->cvolume.values[channel]);

    return (value == PA_DECIBEL_MININFTY) ? -MATE_MIXER_INFINITY : value;
}

static gboolean
pulse_stream_control_set_channel_decibel (MateMixerStreamControl *mmsc,
                                          guint                   channel,
                                          gdouble                 decibel)
{
    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), FALSE);

    return pulse_stream_control_set_channel_volume (mmsc,
                                                    channel,
                                                    pa_sw_volume_from_dB (decibel));
}

static MateMixerChannelPosition
pulse_stream_control_get_channel_position (MateMixerStreamControl *mmsc, guint channel)
{
    PulseStreamControl *control;

    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), MATE_MIXER_CHANNEL_UNKNOWN);

    control = PULSE_STREAM_CONTROL (mmsc);

    if (channel >= control->priv->channel_map.channels)
        return MATE_MIXER_CHANNEL_UNKNOWN;

    if (control->priv->channel_map.map[channel] == PA_CHANNEL_POSITION_INVALID)
        return MATE_MIXER_CHANNEL_UNKNOWN;

    return pulse_channel_map_from[control->priv->channel_map.map[channel]];
}

static gboolean
pulse_stream_control_has_channel_position (MateMixerStreamControl  *mmsc,
                                           MateMixerChannelPosition position)
{
    PulseStreamControl *control;

    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), FALSE);

    control = PULSE_STREAM_CONTROL (mmsc);

    /* Handle invalid position as a special case, otherwise this function would
     * return TRUE for e.g. unknown index in a default channel map */
    if (pulse_channel_map_to[position] == PA_CHANNEL_POSITION_INVALID)
        return FALSE;

    if (pa_channel_map_has_position (&control->priv->channel_map,
                                     pulse_channel_map_to[position]) != 0)
        return TRUE;
    else
        return FALSE;
}

static gboolean
pulse_stream_control_set_balance (MateMixerStreamControl *mmsc, gfloat balance)
{
    PulseStreamControl *control;
    pa_cvolume          cvolume;

    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), FALSE);

    control = PULSE_STREAM_CONTROL (mmsc);
    cvolume = control->priv->cvolume;

    if (pa_cvolume_set_balance (&cvolume, &control->priv->channel_map, balance) == NULL)
        return FALSE;

    return set_cvolume (control, &cvolume);
}

static gboolean
pulse_stream_control_set_fade (MateMixerStreamControl *mmsc, gfloat fade)
{
    PulseStreamControl *control;
    pa_cvolume          cvolume;

    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), FALSE);

    control = PULSE_STREAM_CONTROL (mmsc);
    cvolume = control->priv->cvolume;

    if (pa_cvolume_set_fade (&cvolume, &control->priv->channel_map, fade) == NULL)
        return FALSE;

    return set_cvolume (control, &cvolume);
}

static gboolean
pulse_stream_control_get_monitor_enabled (MateMixerStreamControl *mmsc)
{
    PulseStreamControl *control;

    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), FALSE);

    control = PULSE_STREAM_CONTROL (mmsc);

    if (control->priv->monitor != NULL)
        return pulse_monitor_get_enabled (control->priv->monitor);

    return FALSE;
}

static gboolean
pulse_stream_control_set_monitor_enabled (MateMixerStreamControl *mmsc, gboolean enabled)
{
    PulseStreamControl *control;

    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), FALSE);

    control = PULSE_STREAM_CONTROL (mmsc);

    if (enabled == TRUE) {
        if (control->priv->monitor == NULL) {
            control->priv->monitor =
                PULSE_STREAM_CONTROL_GET_CLASS (control)->create_monitor (control);

            if G_UNLIKELY (control->priv->monitor == NULL)
                return FALSE;

            g_signal_connect (G_OBJECT (control->priv->monitor),
                              "value",
                              G_CALLBACK (on_monitor_value),
                              control);
        }
    } else {
        if (control->priv->monitor == NULL)
            return FALSE;
    }
    return pulse_monitor_set_enabled (control->priv->monitor, enabled);
}

static guint
pulse_stream_control_get_min_volume (MateMixerStreamControl *mmsc)
{
    return (guint) PA_VOLUME_MUTED;
}

static guint
pulse_stream_control_get_max_volume (MateMixerStreamControl *mmsc)
{
    MateMixerStreamControlFlags flags;

    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), (guint) PA_VOLUME_MUTED);

    flags = mate_mixer_stream_control_get_flags (mmsc);

    /*
     * From PulseAudio wiki:
     * For all volumes that are > PA_VOLUME_NORM (i.e. beyond the maximum volume
     * setting of the hw) PA will do digital amplification. This works only for
     * devices that have PA_SINK_DECIBEL_VOLUME/PA_SOURCE_DECIBEL_VOLUME set. For
     * devices that lack this flag do not extend the volume slider like this, it
     * will not have any effect.
     */
    if (flags & MATE_MIXER_STREAM_CONTROL_HAS_DECIBEL)
        return (guint) PA_VOLUME_UI_MAX;
    else
        return (guint) PA_VOLUME_NORM;
}

static guint
pulse_stream_control_get_normal_volume (MateMixerStreamControl *mmsc)
{
    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), (guint) PA_VOLUME_MUTED);

    return (guint) PA_VOLUME_NORM;
}

static guint
pulse_stream_control_get_base_volume (MateMixerStreamControl *mmsc)
{
    PulseStreamControl *control;

    g_return_val_if_fail (PULSE_IS_STREAM_CONTROL (mmsc), (guint) PA_VOLUME_MUTED);

    control = PULSE_STREAM_CONTROL (mmsc);

    if (control->priv->base_volume > 0)
        return (guint) control->priv->base_volume;
    else
        return (guint) PA_VOLUME_NORM;
}

static void
on_monitor_value (PulseMonitor *monitor, gdouble value, PulseStreamControl *control)
{
    g_signal_emit_by_name (G_OBJECT (control),
                           "monitor-value",
                           value);
}

static void
set_balance_fade (PulseStreamControl *control)
{
    gfloat value;

    /* PulseAudio returns the default 0.0f value on error, so skip checking validity
     * of the channel map and cvolume */
    value = pa_cvolume_get_balance (&control->priv->cvolume,
                                    &control->priv->channel_map);

    _mate_mixer_stream_control_set_balance (MATE_MIXER_STREAM_CONTROL (control), value);

    value = pa_cvolume_get_fade (&control->priv->cvolume,
                                 &control->priv->channel_map);

    _mate_mixer_stream_control_set_fade (MATE_MIXER_STREAM_CONTROL (control), value);
}

static gboolean
set_cvolume (PulseStreamControl *control, pa_cvolume *cvolume)
{
    PulseStreamControlClass *klass;

    if (pa_cvolume_valid (cvolume) == 0)
        return FALSE;
    if (pa_cvolume_equal (cvolume, &control->priv->cvolume) != 0)
        return TRUE;

    klass = PULSE_STREAM_CONTROL_GET_CLASS (control);

    if (klass->set_volume (control, cvolume) == FALSE)
        return FALSE;

    control->priv->cvolume = *cvolume;
    control->priv->volume  = (guint) pa_cvolume_max (cvolume);

    g_object_notify (G_OBJECT (control), "volume");

    /* Changing volume may change the balance and fade values as well */
    set_balance_fade (control);
    return TRUE;
}