aboutsummaryrefslogtreecommitdiffhomepage
path: root/libao2/ao_alsa.c
blob: 8729dac257b7d8e1a4a3e9e6c3aff88b56e41319 (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
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
/*
  ao_alsa9/1.x - ALSA-0.9.x-1.x output plugin for MPlayer

  (C) Alex Beregszaszi
  
  modified for real alsa-0.9.0-support by Zsolt Barat <joy@streamminister.de>
  additional AC3 passthrough support by Andy Lo A Foe <andy@alsaplayer.org>  
  08/22/2002 iec958-init rewritten and merged with common init, zsolt
  04/13/2004 merged with ao_alsa1.x, fixes provided by Jindrich Makovicka
  04/25/2004 printfs converted to mp_msg, Zsolt.
  
  Any bugreports regarding to this driver are welcome.
*/

#include <errno.h>
#include <sys/time.h>
#include <stdlib.h>
#include <math.h>
#include <string.h>
#include <sys/poll.h>

#include "../config.h"
#include "../mixer.h"
#include "../mp_msg.h"

#define ALSA_PCM_NEW_HW_PARAMS_API
#define ALSA_PCM_NEW_SW_PARAMS_API

#if HAVE_SYS_ASOUNDLIB_H
#include <sys/asoundlib.h>
#elif HAVE_ALSA_ASOUNDLIB_H
#include <alsa/asoundlib.h>
#else
#error "asoundlib.h is not in sys/ or alsa/ - please bugreport"
#endif


#include "audio_out.h"
#include "audio_out_internal.h"
#include "afmt.h"

static ao_info_t info = 
{
    "ALSA-0.9.x-1.x audio output",
    "alsa",
    "Alex Beregszaszi, Zsolt Barat <joy@streamminister.de>",
    "under developement"
};

LIBAO_EXTERN(alsa)

static snd_pcm_t *alsa_handler;
static snd_pcm_format_t alsa_format;
static snd_pcm_hw_params_t *alsa_hwparams;
static snd_pcm_sw_params_t *alsa_swparams;

/* possible 4096, original 8192 
 * was only needed for calculating chunksize? */
static int alsa_fragsize = 4096;
/* 16 sets buffersize to 16 * chunksize is as default 1024
 * which seems to be good avarge for most situations 
 * so buffersize is 16384 frames by default */
static int alsa_fragcount = 16;
static snd_pcm_uframes_t chunk_size = 1024;//is alsa_fragsize / 4

#define MIN_CHUNK_SIZE 1024

static size_t bits_per_sample, bytes_per_sample, bits_per_frame;
static size_t chunk_bytes;

int ao_mmap = 0;
int ao_noblock = 0;
int first = 1;

static int open_mode;
static int set_block_mode;
static int alsa_can_pause = 0;

#define ALSA_DEVICE_SIZE 256

#undef BUFFERTIME
#define SET_CHUNKSIZE
#undef USE_POLL

/* to set/get/query special features/parameters */
static int control(int cmd, void *arg)
{
  switch(cmd) {
  case AOCONTROL_QUERY_FORMAT:
    return CONTROL_TRUE;
#ifndef WORDS_BIGENDIAN 
  case AOCONTROL_GET_VOLUME:
  case AOCONTROL_SET_VOLUME:
    {
      ao_control_vol_t *vol = (ao_control_vol_t *)arg;

      int err;
      snd_mixer_t *handle;
      snd_mixer_elem_t *elem;
      snd_mixer_selem_id_t *sid;

      static char *mix_name = "PCM";
      static char *card = "default";

      long pmin, pmax;
      long get_vol, set_vol;
      float f_multi;

      if(mixer_channel) mix_name = mixer_channel;
      if(mixer_device) card = mixer_device;

      if(ao_data.format == AFMT_AC3)
	return CONTROL_TRUE;

      //allocate simple id
      snd_mixer_selem_id_alloca(&sid);
	
      //sets simple-mixer index and name
      snd_mixer_selem_id_set_index(sid, 0);
      snd_mixer_selem_id_set_name(sid, mix_name);

      if ((err = snd_mixer_open(&handle, 0)) < 0) {
	mp_msg(MSGT_AO,MSGL_ERR,"alsa-control: mixer open error: %s\n", snd_strerror(err));
	return CONTROL_ERROR;
      }

      if ((err = snd_mixer_attach(handle, card)) < 0) {
	mp_msg(MSGT_AO,MSGL_ERR,"alsa-control: mixer attach %s error: %s\n", 
	       card, snd_strerror(err));
	snd_mixer_close(handle);
	return CONTROL_ERROR;
      }

      if ((err = snd_mixer_selem_register(handle, NULL, NULL)) < 0) {
	mp_msg(MSGT_AO,MSGL_ERR,"alsa-control: mixer register error: %s\n", snd_strerror(err));
	snd_mixer_close(handle);
	return CONTROL_ERROR;
      }
      err = snd_mixer_load(handle);
      if (err < 0) {
	mp_msg(MSGT_AO,MSGL_ERR,"alsa-control: mixer load error: %s\n", snd_strerror(err));
	snd_mixer_close(handle);
	return CONTROL_ERROR;
      }

      elem = snd_mixer_find_selem(handle, sid);
      if (!elem) {
	mp_msg(MSGT_AO,MSGL_ERR,"alsa-control: unable to find simple control '%s',%i\n",
	       snd_mixer_selem_id_get_name(sid), snd_mixer_selem_id_get_index(sid));
	snd_mixer_close(handle);
	return CONTROL_ERROR;
	}

      snd_mixer_selem_get_playback_volume_range(elem,&pmin,&pmax);
      f_multi = (100 / (float)(pmax - pmin));

      if (cmd == AOCONTROL_SET_VOLUME) {

	set_vol = vol->left / f_multi + pmin + 0.5;

	//setting channels
	if ((err = snd_mixer_selem_set_playback_volume(elem, 0, set_vol)) < 0) {
	  mp_msg(MSGT_AO,MSGL_ERR,"alsa-control: error setting left channel, %s\n", 
		 snd_strerror(err));
	  return CONTROL_ERROR;
	}
	mp_msg(MSGT_AO,MSGL_DBG2,"left=%li, ", set_vol);

	set_vol = vol->right / f_multi + pmin + 0.5;

	if ((err = snd_mixer_selem_set_playback_volume(elem, 1, set_vol)) < 0) {
	  mp_msg(MSGT_AO,MSGL_ERR,"alsa-control: error setting right channel, %s\n", 
		 snd_strerror(err));
	  return CONTROL_ERROR;
	}
	mp_msg(MSGT_AO,MSGL_DBG2,"right=%li, pmin=%li, pmax=%li, mult=%f\n", 
	       set_vol, pmin, pmax, f_multi);
      }
      else {
	snd_mixer_selem_get_playback_volume(elem, 0, &get_vol);
	vol->left = (get_vol - pmin) * f_multi;
	snd_mixer_selem_get_playback_volume(elem, 1, &get_vol);
	vol->right = (get_vol - pmin) * f_multi;

	mp_msg(MSGT_AO,MSGL_DBG2,"left=%f, right=%f\n",vol->left,vol->right);
      }
      snd_mixer_close(handle);
      return CONTROL_OK;
    }
#endif
    
  } //end switch
  return(CONTROL_UNKNOWN);
}

static void parse_device (char *dest, char *src, int len)
{
  char *tmp;
  strncpy (dest, src, len);
  while ((tmp = strrchr(dest, '.')))
    tmp[0] = ',';
  while ((tmp = strrchr(dest, '=')))
    tmp[0] = ':';
}

static void print_help ()
{
  mp_msg (MSGT_AO, MSGL_FATAL,
           "\n-ao alsa commandline help:\n"
           "Example: mplayer -ao alsa:mmap:device=hw=0.3\n"
           "  sets mmap-mode and first card fourth device\n"
           "\nOptions:\n"
           "  mmap\n"
           "    Set memory-mapped mode, experimental\n"
           "  noblock\n"
           "    Sets non-blocking mode\n"
           "  device=<device-name>\n"
           "    Sets device (change , to . and : to =)\n");
}

/*
    open & setup audio device
    return: 1=success 0=fail
*/
static int init(int rate_hz, int channels, int format, int flags)
{
    int err;
    int cards = -1;
    snd_pcm_info_t *alsa_info;
    char *str_block_mode;
    int device_set = 0;
    int dir = 0;
    snd_pcm_uframes_t bufsize;
    char alsa_device[ALSA_DEVICE_SIZE + 1];
    // make sure alsa_device is null-terminated even when using strncpy etc.
    memset(alsa_device, 0, ALSA_DEVICE_SIZE + 1);

    mp_msg(MSGT_AO,MSGL_V,"alsa-init: requested format: %d Hz, %d channels, %s\n", rate_hz,
	channels, audio_out_format_name(format));
    alsa_handler = NULL;
    mp_msg(MSGT_AO,MSGL_V,"alsa-init: compiled for ALSA-%s\n", SND_LIB_VERSION_STR);
    
    if ((err = snd_card_next(&cards)) < 0 || cards < 0)
    {
      mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: no soundcards found: %s\n", snd_strerror(err));
      return(0);
    }

    ao_data.samplerate = rate_hz;
    ao_data.bps = channels * rate_hz;
    ao_data.format = format;
    ao_data.channels = channels;
    ao_data.outburst = OUTBURST;

    switch (format)
      {
      case AFMT_S8:
	alsa_format = SND_PCM_FORMAT_S8;
	break;
      case AFMT_U8:
	alsa_format = SND_PCM_FORMAT_U8;
	break;
      case AFMT_U16_LE:
	alsa_format = SND_PCM_FORMAT_U16_LE;
	break;
      case AFMT_U16_BE:
	alsa_format = SND_PCM_FORMAT_U16_BE;
	break;
#ifndef WORDS_BIGENDIAN
      case AFMT_AC3:
#endif
      case AFMT_S16_LE:
	alsa_format = SND_PCM_FORMAT_S16_LE;
	break;
#ifdef WORDS_BIGENDIAN
      case AFMT_AC3:
#endif
      case AFMT_S16_BE:
	alsa_format = SND_PCM_FORMAT_S16_BE;
	break;
      case AFMT_S32_LE:
	alsa_format = SND_PCM_FORMAT_S32_LE;
	break;
      case AFMT_S32_BE:
	alsa_format = SND_PCM_FORMAT_S32_BE;
	break;
      case AFMT_FLOAT:
	alsa_format = SND_PCM_FORMAT_FLOAT_LE;
	break;

      default:
	alsa_format = SND_PCM_FORMAT_MPEG; //? default should be -1
	break;
      }
    
    //setting bw according to the input-format. resolution seems to be always s16_le or
    //u16_le so 32bit is probably obsolet. 
    switch(alsa_format)
      {
      case SND_PCM_FORMAT_S8:
      case SND_PCM_FORMAT_U8:
	ao_data.bps *= 1;
	break;
      case SND_PCM_FORMAT_S16_LE:
      case SND_PCM_FORMAT_U16_LE:
      case SND_PCM_FORMAT_S16_BE:
      case SND_PCM_FORMAT_U16_BE:
	ao_data.bps *= 2;
	break;
      case SND_PCM_FORMAT_S32_LE:
      case SND_PCM_FORMAT_S32_BE:
      case SND_PCM_FORMAT_FLOAT_LE:
	ao_data.bps *= 4;
	break;
      case -1:
	mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: invalid format (%s) requested - output disabled\n",
	       audio_out_format_name(format));
	return(0);
	break;
      default:
	ao_data.bps *= 2;
	mp_msg(MSGT_AO,MSGL_WARN,"alsa-init: couldn't convert to right format. setting bps to: %d", ao_data.bps);
      }

    //subdevice parsing
    if (ao_subdevice) {
      int parse_err = 0;
      char *parse_pos = &ao_subdevice[0];
      while (parse_pos[0] && !parse_err) {
        if (strncmp (parse_pos, "mmap", 4) == 0) {
          parse_pos = &parse_pos[4];
          ao_mmap = 1;
        } else if (strncmp (parse_pos, "noblock", 7) == 0) {
          parse_pos = &parse_pos[7];
          ao_noblock = 1;
        } else if (strncmp (parse_pos, "device=", 7) == 0) {
          int name_len;
          parse_pos = &parse_pos[7];
          name_len = strcspn (parse_pos, ":");
          if (name_len < 0 || name_len > ALSA_DEVICE_SIZE) {
            parse_err = 1;
            break;
          }
          parse_device (alsa_device, parse_pos, name_len);
          parse_pos = &parse_pos[name_len];
          device_set = 1;
        }
        if (parse_pos[0] == ':') parse_pos = &parse_pos[1];
        else if (parse_pos[0]) parse_err = 1;
      }
      if (parse_err) {
        print_help();
        return 0;
      }
    } else { //end parsing ao_subdevice

        /* in any case for multichannel playback we should select
         * appropriate device
         */
        switch (channels) {
	case 1:
	case 2:
	  mp_msg(MSGT_AO,MSGL_V,"alsa-init: setup for 1/2 channel(s)\n");
	  break;
	case 4:
	  if (alsa_format == SND_PCM_FORMAT_FLOAT_LE)
	    // hack - use the converter plugin
	    strncpy(alsa_device, "plug:surround40", ALSA_DEVICE_SIZE);
	  else
	    strncpy(alsa_device, "surround40", ALSA_DEVICE_SIZE);
	  device_set = 1;
	  mp_msg(MSGT_AO,MSGL_V,"alsa-init: device set to surround40\n");
	  break;
	case 6:
	  if (alsa_format == SND_PCM_FORMAT_FLOAT_LE)
	    strncpy(alsa_device, "plug:surround51", ALSA_DEVICE_SIZE);
	  else
	    strncpy(alsa_device, "surround51", ALSA_DEVICE_SIZE);
	  device_set = 1;
	  mp_msg(MSGT_AO,MSGL_V,"alsa-init: device set to surround51\n");
	  break;
	default:
	  mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: %d channels are not supported\n",channels);
        }
    }

    /* switch for spdif
     * sets opening sequence for SPDIF
     * sets also the playback and other switches 'on the fly'
     * while opening the abstract alias for the spdif subdevice
     * 'iec958'
     */
    if (format == AFMT_AC3) {
      unsigned char s[4];

      switch (channels) {
      case 1:
      case 2:

	s[0] = IEC958_AES0_NONAUDIO | 
	  IEC958_AES0_CON_EMPHASIS_NONE;
	s[1] = IEC958_AES1_CON_ORIGINAL | 
	  IEC958_AES1_CON_PCM_CODER;
	s[2] = 0;
	s[3] = IEC958_AES3_CON_FS_48000;

	snprintf(alsa_device, ALSA_DEVICE_SIZE,
		"iec958:AES0=0x%x,AES1=0x%x,AES2=0x%x,AES3=0x%x", 
 		s[0], s[1], s[2], s[3]);

	mp_msg(MSGT_AO,MSGL_V,"alsa-spdif-init: playing AC3, %i channels\n", channels);
	device_set = 1;
	break;
      case 4:
	strncpy(alsa_device, "surround40", ALSA_DEVICE_SIZE);
	device_set = 1;
	break;
    
      case 6:
	strncpy(alsa_device, "surround51", ALSA_DEVICE_SIZE);
	device_set = 1;
	break;

      default:
	mp_msg(MSGT_AO,MSGL_ERR,"alsa-spdif-init: %d channels are not supported\n", channels);
      }
    }

    if (!device_set)
      {
	int tmp_device, tmp_subdevice, err;

	snd_pcm_info_alloca(&alsa_info);
	
	if ((tmp_device = snd_pcm_info_get_device(alsa_info)) < 0)
	  {
	    mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: can't get device\n");
	  }

	if ((tmp_subdevice = snd_pcm_info_get_subdevice(alsa_info)) < 0)
	  {
	    mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: can't get subdevice\n");
	  }
	
	mp_msg(MSGT_AO,MSGL_INFO,"alsa-init: got device=%i, subdevice=%i\n", 
	       tmp_device, tmp_subdevice);

	//we are setting here device to default cause it could be configured by the user
	//if its not set by the user, it defaults to hw:0,0
	if ((err = snprintf(alsa_device, ALSA_DEVICE_SIZE, "default")) <= 0)
	  {
	    mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: can't write device-id\n");
	  }

	mp_msg(MSGT_AO,MSGL_INFO,"alsa-init: %d soundcard%s found, using: %s\n", cards+1,(cards >= 0) ? "" : "s", alsa_device);
      } else {
		mp_msg(MSGT_AO,MSGL_INFO,"alsa-init: soundcard set to %s\n", alsa_device);
      }

    //setting modes for block or nonblock-mode
    if (ao_noblock) {
      open_mode = SND_PCM_NONBLOCK;
      set_block_mode = 1;
      str_block_mode = "nonblock-mode";
    }
    else {
      open_mode = 0;
      set_block_mode = 0;
      str_block_mode = "block-mode";
    }

    //sets buff/chunksize if its set manually
    if (ao_data.buffersize) {
      switch (ao_data.buffersize)
	{
	case 1:
	  alsa_fragcount = 16;
	  chunk_size = 512;
	    mp_msg(MSGT_AO,MSGL_V,"alsa-init: buffersize set manually to 8192\n");
	    mp_msg(MSGT_AO,MSGL_V,"alsa-init: chunksize set manually to 512\n");
	  break;
	case 2:
	  alsa_fragcount = 8;
	  chunk_size = 1024;
	    mp_msg(MSGT_AO,MSGL_V,"alsa-init: buffersize set manually to 8192\n");
	    mp_msg(MSGT_AO,MSGL_V,"alsa-init: chunksize set manually to 1024\n");
	  break;
	case 3:
	  alsa_fragcount = 32;
	  chunk_size = 512;
	    mp_msg(MSGT_AO,MSGL_V,"alsa-init: buffersize set manually to 16384\n");
	    mp_msg(MSGT_AO,MSGL_V,"alsa-init: chunksize set manually to 512\n");
	  break;
	case 4:
	  alsa_fragcount = 16;
	  chunk_size = 1024;
	    mp_msg(MSGT_AO,MSGL_V,"alsa-init: buffersize set manually to 16384\n");
	    mp_msg(MSGT_AO,MSGL_V,"alsa-init: chunksize set manually to 1024\n");
	  break;
	default:
	  alsa_fragcount = 16;
	  if (ao_mmap)
	    chunk_size = 512;
	  else
	    chunk_size = 1024;
	  break;
	}
    }

    if (!alsa_handler) {
      //modes = 0, SND_PCM_NONBLOCK, SND_PCM_ASYNC
      if ((err = snd_pcm_open(&alsa_handler, alsa_device, SND_PCM_STREAM_PLAYBACK, open_mode)) < 0)
	{
	  if (err != -EBUSY && ao_noblock) {
	    mp_msg(MSGT_AO,MSGL_INFO,"alsa-init: open in nonblock-mode failed, trying to open in block-mode\n");
	    if ((err = snd_pcm_open(&alsa_handler, alsa_device, SND_PCM_STREAM_PLAYBACK, 0)) < 0) {
	      mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: playback open error: %s\n", snd_strerror(err));
	      return(0);
	    } else {
	      set_block_mode = 0;
	      str_block_mode = "block-mode";
	    }
	  } else {
	    mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: playback open error: %s\n", snd_strerror(err));
	    return(0);
	  }
	}

      if ((err = snd_pcm_nonblock(alsa_handler, set_block_mode)) < 0) {
         mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: error set block-mode %s\n", snd_strerror(err));
      } else {
	mp_msg(MSGT_AO,MSGL_V,"alsa-init: pcm opend in %s\n", str_block_mode);
      }

      snd_pcm_hw_params_alloca(&alsa_hwparams);
      snd_pcm_sw_params_alloca(&alsa_swparams);

      // setting hw-parameters
      if ((err = snd_pcm_hw_params_any(alsa_handler, alsa_hwparams)) < 0)
	{
	  mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: unable to get initial parameters: %s\n",
		 snd_strerror(err));
	  return(0);
	}
    
      if (ao_mmap) {
	snd_pcm_access_mask_t *mask = alloca(snd_pcm_access_mask_sizeof());
	snd_pcm_access_mask_none(mask);
	snd_pcm_access_mask_set(mask, SND_PCM_ACCESS_MMAP_INTERLEAVED);
	snd_pcm_access_mask_set(mask, SND_PCM_ACCESS_MMAP_NONINTERLEAVED);
	snd_pcm_access_mask_set(mask, SND_PCM_ACCESS_MMAP_COMPLEX);
	err = snd_pcm_hw_params_set_access_mask(alsa_handler, alsa_hwparams, mask);
	mp_msg(MSGT_AO,MSGL_INFO,"alsa-init: mmap set\n");
      } else {
	err = snd_pcm_hw_params_set_access(alsa_handler, alsa_hwparams,
					   SND_PCM_ACCESS_RW_INTERLEAVED);
      }
      if (err < 0) {
	mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: unable to set access type: %s\n", 
	       snd_strerror(err));
	return (0);
      }

      /* workaround for nonsupported formats
	 sets default format to S16_LE if the given formats aren't supported */
      if ((err = snd_pcm_hw_params_test_format(alsa_handler, alsa_hwparams,
                                             alsa_format)) < 0)
      {
         mp_msg(MSGT_AO,MSGL_INFO,
		"alsa-init: format %s are not supported by hardware, trying default\n", 
		audio_out_format_name(format));
         alsa_format = SND_PCM_FORMAT_S16_LE;
         ao_data.format = AFMT_S16_LE;
         ao_data.bps = channels * rate_hz * 2;
      }

      bytes_per_sample = ao_data.bps / ao_data.samplerate; //it should be here

    
      if ((err = snd_pcm_hw_params_set_format(alsa_handler, alsa_hwparams,
					      alsa_format)) < 0)
	{
	  mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: unable to set format: %s\n",
		 snd_strerror(err));
	}

      if ((err = snd_pcm_hw_params_set_channels(alsa_handler, alsa_hwparams,
						ao_data.channels)) < 0)
	{
	  mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: unable to set channels: %s\n",
		 snd_strerror(err));
	}

      if ((err = snd_pcm_hw_params_set_rate_near(alsa_handler, alsa_hwparams, 
						 &ao_data.samplerate, &dir)) < 0) 
        {
	  mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: unable to set samplerate-2: %s\n",
		 snd_strerror(err));
	  return(0);
        }

#ifdef BUFFERTIME
      {
	int alsa_buffer_time = 500000; /* original 60 */
	int alsa_period_time;
	alsa_period_time = alsa_buffer_time/4;
	if ((err = snd_pcm_hw_params_set_buffer_time_near(alsa_handler, alsa_hwparams, 
							  &alsa_buffer_time, &dir)) < 0)
	  {
	    mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: unable to set buffer time near: %s\n",
		   snd_strerror(err));
	    return(0);
	  } else
	    alsa_buffer_time = err;

	if ((err = snd_pcm_hw_params_set_period_time_near(alsa_handler, alsa_hwparams, 
							  &alsa_period_time, &dir)) < 0)
	  /* original: alsa_buffer_time/ao_data.bps */
	  {
	    mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: unable to set period time: %s\n",
		   snd_strerror(err));
	  }
	mp_msg(MSGT_AO,MSGL_INFO,"alsa-init: buffer_time: %d, period_time :%d\n",
	       alsa_buffer_time, err);
      } 
#endif//end SET_BUFFERTIME

#ifdef SET_CHUNKSIZE
      {
	//set chunksize
	dir=0;
	if ((err = snd_pcm_hw_params_set_period_size_near(alsa_handler, alsa_hwparams, 
							  &chunk_size, &dir)) < 0)
	  {
	    mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: unable to set periodsize(%d): %s\n",
			    chunk_size, snd_strerror(err));
	  }
	else {
	  mp_msg(MSGT_AO,MSGL_V,"alsa-init: chunksize set to %i\n", chunk_size);
	}
	if ((err = snd_pcm_hw_params_set_periods_near(alsa_handler, alsa_hwparams,
						      &alsa_fragcount, &dir)) < 0) {
	  mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: unable to set periods: %s\n", 
		 snd_strerror(err));
	}
	else {
	  mp_msg(MSGT_AO,MSGL_V,"alsa-init: fragcount=%i\n", alsa_fragcount);
	}
      }
#endif//end SET_CHUNKSIZE

      /* finally install hardware parameters */
      if ((err = snd_pcm_hw_params(alsa_handler, alsa_hwparams)) < 0)
	{
	  mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: unable to set hw-parameters: %s\n",
		 snd_strerror(err));
	}
      // end setting hw-params


      // gets buffersize for control
      if ((err = snd_pcm_hw_params_get_buffer_size(alsa_hwparams, &bufsize)) < 0)
	{
	  mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: unable to get buffersize: %s\n", snd_strerror(err));
	}
      else {
	ao_data.buffersize = bufsize * bytes_per_sample;
	  mp_msg(MSGT_AO,MSGL_V,"alsa-init: got buffersize=%i\n", ao_data.buffersize);
      }

      // setting sw-params (only avail-min) if noblocking mode was choosed
      if (ao_noblock)
	{

	  if ((err = snd_pcm_sw_params_current(alsa_handler, alsa_swparams)) < 0)
	    {
	      mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: unable to get parameters: %s\n",
		     snd_strerror(err));

	    }

	  //set min available frames to consider pcm ready (4)
	  //increased for nonblock-mode should be set dynamically later
	  if ((err = snd_pcm_sw_params_set_avail_min(alsa_handler, alsa_swparams, 4)) < 0)
	    {
	      mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: unable to set avail_min %s\n",
		     snd_strerror(err));
	    }

	  if ((err = snd_pcm_sw_params(alsa_handler, alsa_swparams)) < 0)
	    {
	      mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: unable to install sw-params\n");
	    }

	  bits_per_sample = snd_pcm_format_physical_width(alsa_format);
	  bits_per_frame = bits_per_sample * channels;
	  chunk_bytes = chunk_size * bits_per_frame / 8;

	    mp_msg(MSGT_AO,MSGL_V,"alsa-init: bits per sample (bps)=%i, bits per frame (bpf)=%i, chunk_bytes=%i\n",bits_per_sample,bits_per_frame,chunk_bytes);}
	//end swparams

      if ((err = snd_pcm_prepare(alsa_handler)) < 0)
	{
	  mp_msg(MSGT_AO,MSGL_ERR,"alsa-init: pcm prepare error: %s\n", snd_strerror(err));
	}

      mp_msg(MSGT_AO,MSGL_INFO,"alsa: %d Hz/%d channels/%d bpf/%d bytes buffer/%s\n",
	     ao_data.samplerate, ao_data.channels, bytes_per_sample, ao_data.buffersize,
	     snd_pcm_format_description(alsa_format));

    } // end switch alsa_handler (spdif)
    alsa_can_pause = snd_pcm_hw_params_can_pause(alsa_hwparams);
    return(1);
} // end init


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

  if (alsa_handler) {
    int err;

    if (!ao_noblock) {
      if ((err = snd_pcm_drop(alsa_handler)) < 0)
	{
	  mp_msg(MSGT_AO,MSGL_ERR,"alsa-uninit: pcm drop error: %s\n", snd_strerror(err));
	  return;
	}
    }

    if ((err = snd_pcm_close(alsa_handler)) < 0)
      {
	mp_msg(MSGT_AO,MSGL_ERR,"alsa-uninit: pcm close error: %s\n", snd_strerror(err));
	return;
      }
    else {
      alsa_handler = NULL;
      mp_msg(MSGT_AO,MSGL_INFO,"alsa-uninit: pcm closed\n");
    }
  }
  else {
    mp_msg(MSGT_AO,MSGL_ERR,"alsa-uninit: no handler defined!\n");
  }
}

static void audio_pause()
{
    int err;

    if (alsa_can_pause) {
        if ((err = snd_pcm_pause(alsa_handler, 1)) < 0)
        {
            mp_msg(MSGT_AO,MSGL_ERR,"alsa-pause: pcm pause error: %s\n", snd_strerror(err));
            return;
        }
          mp_msg(MSGT_AO,MSGL_V,"alsa-pause: pause supported by hardware\n");
    } else {
        if ((err = snd_pcm_drop(alsa_handler)) < 0)
        {
            mp_msg(MSGT_AO,MSGL_ERR,"alsa-pause: pcm drop error: %s\n", snd_strerror(err));
            return;
        }
    }
}

static void audio_resume()
{
    int err;

    if (alsa_can_pause) {
        if ((err = snd_pcm_pause(alsa_handler, 0)) < 0)
        {
            mp_msg(MSGT_AO,MSGL_ERR,"alsa-resume: pcm resume error: %s\n", snd_strerror(err));
            return;
        }
          mp_msg(MSGT_AO,MSGL_V,"alsa-resume: resume supported by hardware\n");
    } else {
        if ((err = snd_pcm_prepare(alsa_handler)) < 0)
        {
           mp_msg(MSGT_AO,MSGL_ERR,"alsa-resume: pcm prepare error: %s\n", snd_strerror(err));
            return;
        }
    }
}

/* stop playing and empty buffers (for seeking/pause) */
static void reset()
{
    int err;

    if ((err = snd_pcm_drop(alsa_handler)) < 0)
    {
	mp_msg(MSGT_AO,MSGL_ERR,"alsa-reset: pcm drop error: %s\n", snd_strerror(err));
	return;
    }
    if ((err = snd_pcm_prepare(alsa_handler)) < 0)
    {
	mp_msg(MSGT_AO,MSGL_ERR,"alsa-reset: pcm prepare error: %s\n", snd_strerror(err));
	return;
    }
    return;
}

#ifdef USE_POLL
static int wait_for_poll(snd_pcm_t *handle, struct pollfd *ufds, unsigned int count)
{
  unsigned short revents;

  while (1) {
    poll(ufds, count, -1);
    snd_pcm_poll_descriptors_revents(handle, ufds, count, &revents);
    if (revents & POLLERR)
      return -EIO;
    if (revents & POLLOUT)
      return 0;
  }
} 
#endif

#ifndef timersub
#define timersub(a, b, result) \
do { \
	(result)->tv_sec = (a)->tv_sec - (b)->tv_sec; \
  (result)->tv_usec = (a)->tv_usec - (b)->tv_usec; \
  if ((result)->tv_usec < 0) { \
		--(result)->tv_sec; \
		(result)->tv_usec += 1000000; \
	} \
} while (0)
#endif

/* I/O error handler */
static int xrun(u_char *str_mode)
{
  int err;
  snd_pcm_status_t *status;

  snd_pcm_status_alloca(&status);
  
  if ((err = snd_pcm_status(alsa_handler, status))<0) {
    mp_msg(MSGT_AO,MSGL_ERR,"status error: %s", snd_strerror(err));
    return(0);
  }

  if (snd_pcm_status_get_state(status) == SND_PCM_STATE_XRUN) {
    struct timeval now, diff, tstamp;
    gettimeofday(&now, 0);
    snd_pcm_status_get_trigger_tstamp(status, &tstamp);
    timersub(&now, &tstamp, &diff);
    mp_msg(MSGT_AO,MSGL_INFO,"alsa-%s: xrun of at least %.3f msecs. resetting stream\n",
	   str_mode,
	   diff.tv_sec * 1000 + diff.tv_usec / 1000.0);
  }

  if ((err = snd_pcm_prepare(alsa_handler))<0) {
    mp_msg(MSGT_AO,MSGL_ERR,"xrun: prepare error: %s", snd_strerror(err));
    return(0);
  }

  return(1); /* ok, data should be accepted again */
}

static int play_normal(void* data, int len);
static int play_mmap(void* data, int len);

static int play(void* data, int len, int flags)
{
  int result;
  if (ao_mmap)
    result = play_mmap(data, len);
  else
    result = play_normal(data, len);

  return result;
}

/*
    plays 'len' bytes of 'data'
    returns: number of bytes played
    modified last at 29.06.02 by jp
    thanxs for marius <marius@rospot.com> for giving us the light ;)
*/

static int play_normal(void* data, int len)
{

  //bytes_per_sample is always 4 for 2 chn S16_LE
  int num_frames = len / bytes_per_sample;
  char *output_samples = (char *)data;
  snd_pcm_sframes_t res = 0;

  //mp_msg(MSGT_AO,MSGL_ERR,"alsa-play: frames=%i, len=%i\n",num_frames,len);

  if (!alsa_handler) {
    mp_msg(MSGT_AO,MSGL_ERR,"alsa-play: device configuration error");
    return 0;
  }

  while (num_frames > 0) {

    res = snd_pcm_writei(alsa_handler, (void *)output_samples, num_frames);

      if (res == -EAGAIN) {
	snd_pcm_wait(alsa_handler, 1000);
      }
      else if (res == -EPIPE) {  /* underrun */
	if (xrun("play") <= 0) {
	  mp_msg(MSGT_AO,MSGL_ERR,"alsa-play: xrun reset error");
	  return(0);
	}
      }
      else if (res == -ESTRPIPE) {	/* suspend */
	mp_msg(MSGT_AO,MSGL_INFO,"alsa-play: pcm in suspend mode. trying to resume\n");
	while ((res = snd_pcm_resume(alsa_handler)) == -EAGAIN)
	  sleep(1);
      }
      else if (res < 0) {
	mp_msg(MSGT_AO,MSGL_INFO,"alsa-play: unknown status, trying to reset soundcard\n");
	if ((res = snd_pcm_prepare(alsa_handler)) < 0) {
	   mp_msg(MSGT_AO,MSGL_ERR,"alsa-play: snd prepare error");
	  return(0);
	  break;
	}
      }

      if (res > 0) {

	/* output_samples += ao_data.channels * res; */
	output_samples += res * bytes_per_sample;

	num_frames -= res;
      }

  } //end while

  if (res < 0) {
    mp_msg(MSGT_AO,MSGL_ERR,"alsa-play: write error %s", snd_strerror(res));
    return 0;
  }
  return len - len % bytes_per_sample;
}

/* mmap-mode mainly based on descriptions by Joshua Haberman <joshua@haberman.com>
 * 'An overview of the ALSA API' http://people.debian.org/~joshua/x66.html
 * and some help by Paul Davis <pbd@op.net> */

static int play_mmap(void* data, int len)
{
  snd_pcm_sframes_t commitres, frames_available;
  snd_pcm_uframes_t frames_transmit, size, offset;
  const snd_pcm_channel_area_t *area;
  void *outbuffer;
  int result;

#ifdef USE_POLL //seems not really be needed
  struct pollfd *ufds;
  int count;

  count = snd_pcm_poll_descriptors_count (alsa_handler);
  ufds = malloc(sizeof(struct pollfd) * count);
  snd_pcm_poll_descriptors(alsa_handler, ufds, count);

  //first wait_for_poll
    if (err = (wait_for_poll(alsa_handler, ufds, count) < 0)) {
      if (snd_pcm_state(alsa_handler) == SND_PCM_STATE_XRUN || 
	  snd_pcm_state(alsa_handler) == SND_PCM_STATE_SUSPENDED) {
        xrun("play");
      }
    }
#endif

  outbuffer = alloca(ao_data.buffersize);

  //don't trust get_space() ;)
  frames_available = snd_pcm_avail_update(alsa_handler) * bytes_per_sample;
  if (frames_available < 0)
    xrun("play");

  if (frames_available < 4) {
    if (first) {
      first = 0;
      snd_pcm_start(alsa_handler);
    }
    else { //FIXME should break and return 0?
      snd_pcm_wait(alsa_handler, -1);
      first = 1;
    }
  }

  /* len is simply the available bufferspace got by get_space() 
   * but real avail_buffer in frames is ab/bytes_per_sample */
  size = len / bytes_per_sample;

  //mp_msg(MSGT_AO,MSGL_V,"len: %i size %i, f_avail %i, bps %i ...\n", len, size, frames_available, bytes_per_sample);

  frames_transmit = size;

  /* prepare areas and set sw-pointers
   * frames_transmit returns the real available buffer-size
   * sometimes != frames_available cause of ringbuffer 'emulation' */
  snd_pcm_mmap_begin(alsa_handler, &area, &offset, &frames_transmit);

  /* this is specific to interleaved streams (or non-interleaved
   * streams with only one channel) */
  outbuffer = ((char *) area->addr + (area->first + area->step * offset) / 8); //8

  //write data
  memcpy(outbuffer, data, (frames_transmit * bytes_per_sample));

  commitres = snd_pcm_mmap_commit(alsa_handler, offset, frames_transmit);

  if (commitres < 0 || commitres != frames_transmit) {
    if (snd_pcm_state(alsa_handler) == SND_PCM_STATE_XRUN || 
	snd_pcm_state(alsa_handler) == SND_PCM_STATE_SUSPENDED) {
      xrun("play");
    }
  }

  //mp_msg(MSGT_AO,MSGL_V,"mmap ft: %i, cres: %i\n", frames_transmit, commitres);

  /* 	err = snd_pcm_area_copy(&area, offset, &data, offset, len, alsa_format); */
  /* 	if (err < 0) { */
  /* 	  mp_msg(MSGT_AO,MSGL_ERR,"area-copy-error\n"); */
  /* 	  return 0; */
  /* 	} */


  //calculate written frames!
  result = commitres * bytes_per_sample;


  /* if (verbose) { */
  /* if (len == result) */
  /* mp_msg(MSGT_AO,MSGL_V,"result: %i, frames written: %i ...\n", result, frames_transmit); */
  /* else */
  /* mp_msg(MSGT_AO,MSGL_V,"result: %i, frames written: %i, result != len ...\n", result, frames_transmit); */
  /* } */

  //mplayer doesn't like -result
  if (result < 0)
    result = 0;

#ifdef USE_POLL
  free(ufds);
#endif

  return result;
}

/* how many byes are free in the buffer */
static int get_space()
{
    snd_pcm_status_t *status;
    int ret;
    char *str_status;

    //snd_pcm_sframes_t avail_frames = 0;
    
    snd_pcm_status_alloca(&status);
    
    if ((ret = snd_pcm_status(alsa_handler, status)) < 0)
    {
	mp_msg(MSGT_AO,MSGL_ERR,"alsa-space: cannot get pcm status: %s\n", snd_strerror(ret));
	return(0);
    }
    
    switch(snd_pcm_status_get_state(status))
    {
    case SND_PCM_STATE_OPEN:
      str_status = "open";
      ret = snd_pcm_status_get_avail(status) * bytes_per_sample;
      break;
    case SND_PCM_STATE_PREPARED:
	str_status = "prepared";
	first = 1;
	ret = snd_pcm_status_get_avail(status) * bytes_per_sample;
	if (ret == 0) //ugly workaround for hang in mmap-mode
	  ret = 10;
	break;
    case SND_PCM_STATE_RUNNING:
      ret = snd_pcm_status_get_avail(status) * bytes_per_sample;
      //avail_frames = snd_pcm_avail_update(alsa_handler) * bytes_per_sample;
      if (str_status != "open" && str_status != "prepared")
	str_status = "running";
      break;
    case SND_PCM_STATE_PAUSED:
      mp_msg(MSGT_AO,MSGL_V,"alsa-space: paused");
      str_status = "paused";
      ret = 0;
      break;
    case SND_PCM_STATE_XRUN:
      xrun("space");
      str_status = "xrun";
      first = 1;
      ret = 0;
      break;
    default:
      str_status = "undefined";
      ret = snd_pcm_status_get_avail(status) * bytes_per_sample;
      if (ret <= 0) {
	xrun("space");
      }
    }

    if (snd_pcm_status_get_state(status) != SND_PCM_STATE_RUNNING)
      mp_msg(MSGT_AO,MSGL_V,"alsa-space: free space = %i, %s --\n", ret, str_status);
    
    if (ret < 0) {
      mp_msg(MSGT_AO,MSGL_ERR,"negative value!!\n");
      ret = 0;
    }
 
    // workaround for too small value returned
    if (ret < MIN_CHUNK_SIZE)
      ret = 0;

    return(ret);
}

/* delay in seconds between first and last sample in buffer */
static float get_delay()
{

  if (alsa_handler) {

    snd_pcm_status_t *status;
    float ret;
    
    snd_pcm_status_alloca(&status);
    
    if ((ret = snd_pcm_status(alsa_handler, status)) < 0)
    {
	mp_msg(MSGT_AO,MSGL_ERR,"alsa-delay: cannot get pcm status: %s\n", snd_strerror(ret));
    }
    
    switch(snd_pcm_status_get_state(status))
    {
	case SND_PCM_STATE_OPEN:
	case SND_PCM_STATE_PREPARED:
	case SND_PCM_STATE_RUNNING:
	    ret = (float)snd_pcm_status_get_delay(status)/(float)ao_data.samplerate;
	    break;
	default:
	    ret = 0;
    }
    

    if (ret < 0)
      ret = 0;
    return(ret);
    
  } else {
    return(0);
  }
}