aboutsummaryrefslogtreecommitdiffhomepage
path: root/libao2/ao_nas.c
blob: 4888cfc366f6594ada7c28a90ad35c8cb2b0db3d (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
/*
 * NAS output plugin for mplayer
 *
 * based on the libaudiooss parts rewritten by me, which were
 * originally based on the NAS output plugin for xmms.
 *
 * xmms plugin by Willem Monsuwe
 * adapted for libaudiooss by Jon Trulson
 * further modified by Erik Inge Bolsø
 * largely rewritten and used for this
 * plugin by Tobias Diedrich
 *
 * Theory of operation:
 *
 * The NAS consists of two parts, a server daemon and a client.
 * We setup the server to use a buffer of size bytes_per_second
 * with a low watermark of buffer_size - NAS_FRAG_SIZE.
 * Upon starting the flow the server will generate a buffer underrun
 * event and the event handler will fill the buffer for the first time.
 * Now the server will generate a lowwater event when the server buffer
 * falls below the low watermark value. The event handler gets called
 * again and refills the buffer by the number of bytes requested by the
 * server (usually a multiple of 4096). To prevent stuttering on
 * startup (start of playing, seeks, unpausing) the client buffer should
 * be bigger than the server buffer. (For debugging we also do some
 * accounting of what we think how much of the server buffer is filled)
 */

#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include <limits.h>
#include <audio/audiolib.h>

#include "config.h"
#include "mp_msg.h"

#include "audio_out.h"
#include "audio_out_internal.h"
#include "libaf/af_format.h"

#define NAS_FRAG_SIZE 4096

static char *nas_event_types[] = {
	"Undefined",
	"Undefined",
	"ElementNotify",
	"GrabNotify",
	"MonitorNotify",
	"BucketNotify",
	"DeviceNotify"
};

static char *nas_elementnotify_kinds[] = {
	"LowWater",
	"HighWater",
	"State",
	"Unknown"
};

static char *nas_states[] = {
	"Stop",
	"Start",
	"Pause",
	"Any"
};

static char *nas_reasons[] = {
	"User",
	"Underrun",
	"Overrun",
	"EOF",
	"Watermark",
	"Hardware",
	"Any"
};

static char* nas_reason(unsigned int reason)
{
	if (reason > 6) reason = 6;
	return nas_reasons[reason];
}

static char* nas_elementnotify_kind(unsigned int kind)
{
	if (kind > 2) kind = 3;
	return nas_elementnotify_kinds[kind];
}

static char* nas_event_type(unsigned int type) {
	if (type > 6) type = 0;
	return nas_event_types[type];
}

static char* nas_state(unsigned int state) {
	if (state>3) state = 3;
	return nas_states[state];
}

static ao_info_t info = 
{
	"NAS audio output",
	"nas",
	"Tobias Diedrich <ranma+mplayer@tdiedrich.de>",
	""
};

struct ao_nas_data {
	AuServer	*aud;
	AuFlowID	flow;
	AuDeviceID	dev;
	AuFixedPoint	gain;

	unsigned int state;
	int expect_underrun;

	void *client_buffer;
	void *server_buffer;
	unsigned int client_buffer_size;
	unsigned int client_buffer_used;
	unsigned int server_buffer_size;
	unsigned int server_buffer_used;
	pthread_mutex_t buffer_mutex;

	pthread_t event_thread;
	int stop_thread;
};

static struct ao_nas_data *nas_data;

LIBAO_EXTERN(nas)

static void nas_print_error(AuServer *aud, const char *prefix, AuStatus as)
{
	char s[100];
	AuGetErrorText(aud, as, s, 100);
	mp_msg(MSGT_AO, MSGL_ERR, "ao_nas: %s: returned status %d (%s)\n", prefix, as, s);
}

static int nas_readBuffer(struct ao_nas_data *nas_data, int num)
{
	AuStatus as;

	pthread_mutex_lock(&nas_data->buffer_mutex);
	mp_msg(MSGT_AO, MSGL_DBG2, "ao_nas: nas_readBuffer(): num=%d client=%d/%d server=%d/%d\n",
			num,
			nas_data->client_buffer_used, nas_data->client_buffer_size,
			nas_data->server_buffer_used, nas_data->server_buffer_size);

	if (nas_data->client_buffer_used == 0) {
		mp_msg(MSGT_AO, MSGL_DBG2, "ao_nas: buffer is empty, nothing read.\n");
		pthread_mutex_unlock(&nas_data->buffer_mutex);
		return 0;
	}
	if (num > nas_data->client_buffer_used)
		num = nas_data->client_buffer_used;

	/*
	 * It is not appropriate to call AuWriteElement() here because the
	 * buffer is locked and delays writing to the network will cause
	 * other threads to block waiting for buffer_mutex.  Instead the
	 * data is copied to "server_buffer" and written to the network
	 * outside of the locked section of code.
	 *
	 * (Note: Rather than these two buffers, a single circular buffer
	 *  could eliminate the memcpy/memmove steps.)
	 */
	/* make sure we don't overflow the buffer */
	if (num > nas_data->server_buffer_size)
		num = nas_data->server_buffer_size;
	memcpy(nas_data->server_buffer, nas_data->client_buffer, num);

	nas_data->client_buffer_used -= num;
	nas_data->server_buffer_used += num;
	memmove(nas_data->client_buffer, nas_data->client_buffer + num, nas_data->client_buffer_used);
	pthread_mutex_unlock(&nas_data->buffer_mutex);

	/*
	 * Now write the new buffer to the network.
	 */
	AuWriteElement(nas_data->aud, nas_data->flow, 0, num, nas_data->server_buffer, AuFalse, &as);
	if (as != AuSuccess) 
		nas_print_error(nas_data->aud, "nas_readBuffer(): AuWriteElement", as);

	return num;
}

static int nas_writeBuffer(struct ao_nas_data *nas_data, void *data, int len)
{
	pthread_mutex_lock(&nas_data->buffer_mutex);
	mp_msg(MSGT_AO, MSGL_DBG2, "ao_nas: nas_writeBuffer(): len=%d client=%d/%d server=%d/%d\n",
			len, nas_data->client_buffer_used, nas_data->client_buffer_size,
			nas_data->server_buffer_used, nas_data->server_buffer_size);

	/* make sure we don't overflow the buffer */
	if (len > nas_data->client_buffer_size - nas_data->client_buffer_used)
		len = nas_data->client_buffer_size - nas_data->client_buffer_used;
	memcpy(nas_data->client_buffer + nas_data->client_buffer_used, data, len);
	nas_data->client_buffer_used += len;

	pthread_mutex_unlock(&nas_data->buffer_mutex);

	return len;
}

static int nas_empty_event_queue(struct ao_nas_data *nas_data)
{
	AuEvent ev;
	int result = 0;
	
	while (AuScanForTypedEvent(nas_data->aud, AuEventsQueuedAfterFlush,
				   AuTrue, AuEventTypeElementNotify, &ev)) {
		AuDispatchEvent(nas_data->aud, &ev);
		result = 1;
	}
	return result;
}

static void *nas_event_thread_start(void *data)
{
	struct ao_nas_data *nas_data = data;

	do {
		mp_msg(MSGT_AO, MSGL_DBG2,
		       "ao_nas: event thread heartbeat (state=%s)\n",
		       nas_state(nas_data->state));
		nas_empty_event_queue(nas_data);
		usleep(1000);
	} while (!nas_data->stop_thread);

	return NULL;
}

static AuBool nas_error_handler(AuServer* aud, AuErrorEvent* ev)
{
	char s[100];
	AuGetErrorText(aud, ev->error_code, s, 100);
	mp_msg(MSGT_AO, MSGL_ERR, "ao_nas: error [%s]\n"
		"error_code: %d\n"
		"request_code: %d\n"
		"minor_code: %d\n",
		s,
		ev->error_code,
		ev->request_code,
		ev->minor_code);

	return AuTrue;
}

static AuBool nas_event_handler(AuServer *aud, AuEvent *ev, AuEventHandlerRec *hnd)
{
	AuElementNotifyEvent *event = (AuElementNotifyEvent *) ev;
	struct ao_nas_data *nas_data = hnd->data;

	mp_msg(MSGT_AO, MSGL_DBG2, "ao_nas: event_handler(): type %s kind %s state %s->%s reason %s numbytes %d expect_underrun %d\n",
		nas_event_type(event->type),
		nas_elementnotify_kind(event->kind),
		nas_state(event->prev_state),
		nas_state(event->cur_state),
		nas_reason(event->reason),
		event->num_bytes,
		nas_data->expect_underrun);

	if (event->num_bytes > INT_MAX) {
		mp_msg(MSGT_AO, MSGL_ERR, "ao_nas: num_bytes > 2GB, server buggy?\n");
	}

	if (event->num_bytes > nas_data->server_buffer_used)
		event->num_bytes = nas_data->server_buffer_used;
	nas_data->server_buffer_used -= event->num_bytes;

	switch (event->reason) {
	case AuReasonWatermark:
		nas_readBuffer(nas_data, event->num_bytes);
		break;
	case AuReasonUnderrun:
		// buffer underrun -> refill buffer
		nas_data->server_buffer_used = 0;
		if (nas_data->expect_underrun) {
			nas_data->expect_underrun = 0;
		} else {
			static int hint = 1;
			mp_msg(MSGT_AO, MSGL_WARN,
			       "ao_nas: Buffer underrun.\n");
			if (hint) {
				hint = 0;
				mp_msg(MSGT_AO, MSGL_HINT,
				       "Possible reasons are:\n"
				       "1) Network congestion.\n"
				       "2) Your NAS server is too slow.\n"
				       "Try renicing your nasd to e.g. -15.\n");
			}
		}
		if (nas_readBuffer(nas_data,
		                   nas_data->server_buffer_size -
		                   nas_data->server_buffer_used) != 0) {
			event->cur_state = AuStateStart;
			break;
		}
		mp_msg(MSGT_AO, MSGL_DBG2,
			"ao_nas: Can't refill buffer, stopping flow.\n");
		AuStopFlow(nas_data->aud, nas_data->flow, NULL);
		break;
	default:
		break;
	}
	nas_data->state=event->cur_state;
	return AuTrue;
}

static AuDeviceID nas_find_device(AuServer *aud, int nch)
{
	int i;
	for (i = 0; i < AuServerNumDevices(aud); i++) {
		AuDeviceAttributes *dev = AuServerDevice(aud, i);
		if ((AuDeviceKind(dev) == AuComponentKindPhysicalOutput) &&
		     AuDeviceNumTracks(dev) == nch) {
			return AuDeviceIdentifier(dev);
		}
	}
	return AuNone;
}

static unsigned int nas_aformat_to_auformat(unsigned int *format)
{
	switch (*format) {
	case	AF_FORMAT_U8:
		return AuFormatLinearUnsigned8;
	case	AF_FORMAT_S8:
		return AuFormatLinearSigned8;
	case	AF_FORMAT_U16_LE:
		return AuFormatLinearUnsigned16LSB;
	case	AF_FORMAT_U16_BE:
		return AuFormatLinearUnsigned16MSB;
	case	AF_FORMAT_S16_LE:
		return AuFormatLinearSigned16LSB;
	case	AF_FORMAT_S16_BE:
		return AuFormatLinearSigned16MSB;
	case	AF_FORMAT_MU_LAW:
		return AuFormatULAW8;
	default:
		*format=AF_FORMAT_S16_NE;
		return nas_aformat_to_auformat(format);
	}
}

// to set/get/query special features/parameters
static int control(int cmd, void *arg)
{
	AuElementParameters aep;
	AuStatus as;
	int retval = CONTROL_UNKNOWN;

	ao_control_vol_t *vol = (ao_control_vol_t *)arg;

	switch (cmd) {
	case AOCONTROL_GET_VOLUME:

		vol->right = (float)nas_data->gain/AU_FIXED_POINT_SCALE*50;
		vol->left = vol->right;

		mp_msg(MSGT_AO, MSGL_DBG2, "ao_nas: AOCONTROL_GET_VOLUME: %08x\n", nas_data->gain);
		retval = CONTROL_OK;
		break;

	case AOCONTROL_SET_VOLUME:
		/*
		 * kn: we should have vol->left == vol->right but i don't
		 * know if something can change it outside of ao_nas
		 * so i take the mean of both values.
		 */
		nas_data->gain = AU_FIXED_POINT_SCALE*((vol->left+vol->right)/2)/50;
		mp_msg(MSGT_AO, MSGL_DBG2, "ao_nas: AOCONTROL_SET_VOLUME: %08x\n", nas_data->gain);

		aep.parameters[AuParmsMultiplyConstantConstant]=nas_data->gain;
		aep.flow = nas_data->flow;
		aep.element_num = 1;
		aep.num_parameters = AuParmsMultiplyConstant;

		AuSetElementParameters(nas_data->aud, 1, &aep, &as);
		if (as != AuSuccess) {
			nas_print_error(nas_data->aud,
			                "control(): AuSetElementParameters", as);
			retval = CONTROL_ERROR;
		} else retval = CONTROL_OK;
		break;
	};

	return retval;
}

// open & setup audio device
// return: 1=success 0=fail
static int init(int rate,int channels,int format,int flags)
{
	AuElement elms[3];
	AuStatus as;
	unsigned char auformat = nas_aformat_to_auformat(&format);
	int bytes_per_sample = channels * AuSizeofFormat(auformat);
	int buffer_size;
	char *server;

	nas_data=malloc(sizeof(struct ao_nas_data));
	memset(nas_data, 0, sizeof(struct ao_nas_data));

	mp_msg(MSGT_AO, MSGL_V, "ao2: %d Hz  %d chans  %s\n",rate,channels,
		af_fmt2str_short(format));

	ao_data.format = format;
	ao_data.samplerate = rate;
	ao_data.channels = channels;
	ao_data.outburst = NAS_FRAG_SIZE;
	ao_data.bps = rate * bytes_per_sample;
	buffer_size = ao_data.bps; /* buffer 1 second */
	/*
	 * round up to multiple of NAS_FRAG_SIZE
	 * divide by 3 first because of 2:1 split
	 */
	buffer_size = (buffer_size/3 + NAS_FRAG_SIZE-1) & ~(NAS_FRAG_SIZE-1);
	ao_data.buffersize = buffer_size*3;

	nas_data->client_buffer_size = buffer_size*2;
	nas_data->client_buffer = malloc(nas_data->client_buffer_size);
	nas_data->server_buffer_size = buffer_size;
	nas_data->server_buffer = malloc(nas_data->server_buffer_size);

	if (!bytes_per_sample) {
		mp_msg(MSGT_AO, MSGL_ERR, "ao_nas: init(): Zero bytes per sample -> nosound\n");
		return 0;
	}

	if (!(server = getenv("AUDIOSERVER")) &&
	    !(server = getenv("DISPLAY"))) {
		mp_msg(MSGT_AO, MSGL_ERR, "ao_nas: init(): AUDIOSERVER environment variable not set -> nosound\n");
		return 0;
	}

	mp_msg(MSGT_AO, MSGL_V, "ao_nas: init(): Using audioserver %s\n", server);

	nas_data->aud = AuOpenServer(server, 0, NULL, 0, NULL, NULL);
	if (!nas_data->aud) { 
		mp_msg(MSGT_AO, MSGL_ERR, "ao_nas: init(): Can't open nas audio server -> nosound\n");
		return 0;
	}

	while (channels>0) {
		nas_data->dev = nas_find_device(nas_data->aud, channels);
		if (nas_data->dev != AuNone &&
		    ((nas_data->flow = AuCreateFlow(nas_data->aud, NULL)) != 0))
			break;
		channels--;
	}

	if (nas_data->flow == 0) {
		mp_msg(MSGT_AO, MSGL_ERR, "ao_nas: init(): Can't find a suitable output device -> nosound\n");
		AuCloseServer(nas_data->aud);
		nas_data->aud = 0;
		return 0;
	}

	AuMakeElementImportClient(elms, rate, auformat, channels, AuTrue,
				buffer_size / bytes_per_sample,
				(buffer_size - NAS_FRAG_SIZE) /
				bytes_per_sample, 0, NULL);
	nas_data->gain = AuFixedPointFromFraction(1, 1);
	AuMakeElementMultiplyConstant(elms+1, 0, nas_data->gain);
	AuMakeElementExportDevice(elms+2, 1, nas_data->dev, rate,
				AuUnlimitedSamples, 0, NULL);
	AuSetElements(nas_data->aud, nas_data->flow, AuTrue, sizeof(elms)/sizeof(*elms), elms, &as);
	if (as != AuSuccess) {
		nas_print_error(nas_data->aud, "init(): AuSetElements", as);
		AuCloseServer(nas_data->aud);
		nas_data->aud = 0;
		return 0;
	}
	AuRegisterEventHandler(nas_data->aud, AuEventHandlerIDMask |
				AuEventHandlerTypeMask,
				AuEventTypeElementNotify, nas_data->flow,
				nas_event_handler, (AuPointer) nas_data);
	AuSetErrorHandler(nas_data->aud, nas_error_handler);
	nas_data->state=AuStateStop;
	nas_data->expect_underrun=0;

	pthread_mutex_init(&nas_data->buffer_mutex, NULL);
	pthread_create(&nas_data->event_thread, NULL, &nas_event_thread_start, nas_data);

	return 1;
}

// close audio device
static void uninit(int immed){

	mp_msg(MSGT_AO, MSGL_DBG3, "ao_nas: uninit()\n");

	nas_data->expect_underrun = 1;
	if (!immed)
	while (nas_data->state != AuStateStop) usleep(1000);
	nas_data->stop_thread = 1;
	pthread_join(nas_data->event_thread, NULL);
	AuCloseServer(nas_data->aud);
	nas_data->aud = 0;
	free(nas_data->client_buffer);
	free(nas_data->server_buffer);
}

// stop playing and empty buffers (for seeking/pause)
static void reset(void){
	AuStatus as;

	mp_msg(MSGT_AO, MSGL_DBG3, "ao_nas: reset()\n");

	pthread_mutex_lock(&nas_data->buffer_mutex);
	nas_data->client_buffer_used = 0;
	pthread_mutex_unlock(&nas_data->buffer_mutex);
	while (nas_data->state != AuStateStop) {
		AuStopFlow(nas_data->aud, nas_data->flow, &as);
		if (as != AuSuccess)
			nas_print_error(nas_data->aud, "reset(): AuStopFlow", as);
		usleep(1000);
	}
}

// stop playing, keep buffers (for pause)
static void audio_pause(void)
{
	AuStatus as;
	mp_msg(MSGT_AO, MSGL_DBG3, "ao_nas: audio_pause()\n");

	AuStopFlow(nas_data->aud, nas_data->flow, &as);
}

// resume playing, after audio_pause()
static void audio_resume(void)
{
	AuStatus as;

	mp_msg(MSGT_AO, MSGL_DBG3, "ao_nas: audio_resume()\n");

	AuStartFlow(nas_data->aud, nas_data->flow, &as);
	if (as != AuSuccess)
		nas_print_error(nas_data->aud,
		                "play(): AuStartFlow", as);
}


// return: how many bytes can be played without blocking
static int get_space(void)
{
	int result;
	
	mp_msg(MSGT_AO, MSGL_DBG3, "ao_nas: get_space()\n");

	pthread_mutex_lock(&nas_data->buffer_mutex);
	result = nas_data->client_buffer_size - nas_data->client_buffer_used;
	pthread_mutex_unlock(&nas_data->buffer_mutex);

	return result;
}

// plays 'len' bytes of 'data'
// it should round it down to outburst*n
// return: number of bytes played
static int play(void* data,int len,int flags)
{
	int maxbursts, playbursts, writelen;
	AuStatus as;

	mp_msg(MSGT_AO, MSGL_DBG3,
	       "ao_nas: play(%p, %d, %d)\n",
	       data, len, flags);

	if (len == 0)
		return 0;

	pthread_mutex_lock(&nas_data->buffer_mutex);
	maxbursts = (nas_data->client_buffer_size -
		     nas_data->client_buffer_used) / ao_data.outburst;
	playbursts = len / ao_data.outburst;
	writelen = (playbursts > maxbursts ? maxbursts : playbursts) *
		   ao_data.outburst;
	pthread_mutex_unlock(&nas_data->buffer_mutex);

	writelen = nas_writeBuffer(nas_data, data, writelen);

	if (nas_data->state != AuStateStart &&
	    maxbursts == playbursts) {
		mp_msg(MSGT_AO, MSGL_DBG2, "ao_nas: play(): Starting flow.\n");
		nas_data->expect_underrun = 1;
		AuStartFlow(nas_data->aud, nas_data->flow, &as);
		if (as != AuSuccess)
			nas_print_error(nas_data->aud, "play(): AuStartFlow", as);
	}

	return writelen;
}

// return: delay in seconds between first and last sample in buffer
static float get_delay(void)
{
	float result;
	
	mp_msg(MSGT_AO, MSGL_DBG3, "ao_nas: get_delay()\n");

	pthread_mutex_lock(&nas_data->buffer_mutex);
	result = ((float)(nas_data->client_buffer_used +
			  nas_data->server_buffer_used)) /
		 (float)ao_data.bps;
	pthread_mutex_unlock(&nas_data->buffer_mutex);

	return result;
}