summaryrefslogtreecommitdiff
path: root/media/libvorbis/lib/vorbis_info.c
blob: 8a2a001f99fa430ba181d9bd92eef35e1d614ac8 (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
/********************************************************************
 *                                                                  *
 * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
 * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
 * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
 * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
 *                                                                  *
 * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2015             *
 * by the Xiph.Org Foundation http://www.xiph.org/                  *
 *                                                                  *
 ********************************************************************

 function: maintain the info structure, info <-> header packets
 last mod: $Id: info.c 19441 2015-01-21 01:17:41Z xiphmont $

 ********************************************************************/

/* general handling of the header and the vorbis_info structure (and
   substructures) */

#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <ogg/ogg.h>
#include "vorbis/codec.h"
#include "codec_internal.h"
#include "codebook.h"
#include "registry.h"
#include "window.h"
#include "psy.h"
#include "misc.h"
#include "os.h"

#define GENERAL_VENDOR_STRING "Xiph.Org libVorbis 1.3.5"
#define ENCODE_VENDOR_STRING "Xiph.Org libVorbis I 20150105 (⛄⛄⛄⛄)"

/* helpers */
static void _v_writestring(oggpack_buffer *o,const char *s, int bytes){

  while(bytes--){
    oggpack_write(o,*s++,8);
  }
}

static void _v_readstring(oggpack_buffer *o,char *buf,int bytes){
  while(bytes--){
    *buf++=oggpack_read(o,8);
  }
}

void vorbis_comment_init(vorbis_comment *vc){
  memset(vc,0,sizeof(*vc));
}

void vorbis_comment_add(vorbis_comment *vc,const char *comment){
  vc->user_comments=_ogg_realloc(vc->user_comments,
                            (vc->comments+2)*sizeof(*vc->user_comments));
  vc->comment_lengths=_ogg_realloc(vc->comment_lengths,
                                  (vc->comments+2)*sizeof(*vc->comment_lengths));
  vc->comment_lengths[vc->comments]=strlen(comment);
  vc->user_comments[vc->comments]=_ogg_malloc(vc->comment_lengths[vc->comments]+1);
  strcpy(vc->user_comments[vc->comments], comment);
  vc->comments++;
  vc->user_comments[vc->comments]=NULL;
}

void vorbis_comment_add_tag(vorbis_comment *vc, const char *tag, const char *contents){
  char *comment=alloca(strlen(tag)+strlen(contents)+2); /* +2 for = and \0 */
  strcpy(comment, tag);
  strcat(comment, "=");
  strcat(comment, contents);
  vorbis_comment_add(vc, comment);
}

/* This is more or less the same as strncasecmp - but that doesn't exist
 * everywhere, and this is a fairly trivial function, so we include it */
static int tagcompare(const char *s1, const char *s2, int n){
  int c=0;
  while(c < n){
    if(toupper(s1[c]) != toupper(s2[c]))
      return !0;
    c++;
  }
  return 0;
}

char *vorbis_comment_query(vorbis_comment *vc, const char *tag, int count){
  long i;
  int found = 0;
  int taglen = strlen(tag)+1; /* +1 for the = we append */
  char *fulltag = alloca(taglen+ 1);

  strcpy(fulltag, tag);
  strcat(fulltag, "=");

  for(i=0;i<vc->comments;i++){
    if(!tagcompare(vc->user_comments[i], fulltag, taglen)){
      if(count == found)
        /* We return a pointer to the data, not a copy */
              return vc->user_comments[i] + taglen;
      else
        found++;
    }
  }
  return NULL; /* didn't find anything */
}

int vorbis_comment_query_count(vorbis_comment *vc, const char *tag){
  int i,count=0;
  int taglen = strlen(tag)+1; /* +1 for the = we append */
  char *fulltag = alloca(taglen+1);
  strcpy(fulltag,tag);
  strcat(fulltag, "=");

  for(i=0;i<vc->comments;i++){
    if(!tagcompare(vc->user_comments[i], fulltag, taglen))
      count++;
  }

  return count;
}

void vorbis_comment_clear(vorbis_comment *vc){
  if(vc){
    long i;
    if(vc->user_comments){
      for(i=0;i<vc->comments;i++)
        if(vc->user_comments[i])_ogg_free(vc->user_comments[i]);
      _ogg_free(vc->user_comments);
    }
    if(vc->comment_lengths)_ogg_free(vc->comment_lengths);
    if(vc->vendor)_ogg_free(vc->vendor);
    memset(vc,0,sizeof(*vc));
  }
}

/* blocksize 0 is guaranteed to be short, 1 is guaranteed to be long.
   They may be equal, but short will never ge greater than long */
int vorbis_info_blocksize(vorbis_info *vi,int zo){
  codec_setup_info *ci = vi->codec_setup;
  return ci ? ci->blocksizes[zo] : -1;
}

/* used by synthesis, which has a full, alloced vi */
void vorbis_info_init(vorbis_info *vi){
  memset(vi,0,sizeof(*vi));
  vi->codec_setup=_ogg_calloc(1,sizeof(codec_setup_info));
}

void vorbis_info_clear(vorbis_info *vi){
  codec_setup_info     *ci=vi->codec_setup;
  int i;

  if(ci){

    for(i=0;i<ci->modes;i++)
      if(ci->mode_param[i])_ogg_free(ci->mode_param[i]);

    for(i=0;i<ci->maps;i++) /* unpack does the range checking */
      if(ci->map_param[i]) /* this may be cleaning up an aborted
                              unpack, in which case the below type
                              cannot be trusted */
        _mapping_P[ci->map_type[i]]->free_info(ci->map_param[i]);

    for(i=0;i<ci->floors;i++) /* unpack does the range checking */
      if(ci->floor_param[i]) /* this may be cleaning up an aborted
                                unpack, in which case the below type
                                cannot be trusted */
        _floor_P[ci->floor_type[i]]->free_info(ci->floor_param[i]);

    for(i=0;i<ci->residues;i++) /* unpack does the range checking */
      if(ci->residue_param[i]) /* this may be cleaning up an aborted
                                  unpack, in which case the below type
                                  cannot be trusted */
        _residue_P[ci->residue_type[i]]->free_info(ci->residue_param[i]);

    for(i=0;i<ci->books;i++){
      if(ci->book_param[i]){
        /* knows if the book was not alloced */
        vorbis_staticbook_destroy(ci->book_param[i]);
      }
      if(ci->fullbooks)
        vorbis_book_clear(ci->fullbooks+i);
    }
    if(ci->fullbooks)
        _ogg_free(ci->fullbooks);

    for(i=0;i<ci->psys;i++)
      _vi_psy_free(ci->psy_param[i]);

    _ogg_free(ci);
  }

  memset(vi,0,sizeof(*vi));
}

/* Header packing/unpacking ********************************************/

static int _vorbis_unpack_info(vorbis_info *vi,oggpack_buffer *opb){
  codec_setup_info     *ci=vi->codec_setup;
  if(!ci)return(OV_EFAULT);

  vi->version=oggpack_read(opb,32);
  if(vi->version!=0)return(OV_EVERSION);

  vi->channels=oggpack_read(opb,8);
  vi->rate=oggpack_read(opb,32);

  vi->bitrate_upper=oggpack_read(opb,32);
  vi->bitrate_nominal=oggpack_read(opb,32);
  vi->bitrate_lower=oggpack_read(opb,32);

  ci->blocksizes[0]=1<<oggpack_read(opb,4);
  ci->blocksizes[1]=1<<oggpack_read(opb,4);

  if(vi->rate<1)goto err_out;
  if(vi->channels<1)goto err_out;
  if(ci->blocksizes[0]<64)goto err_out;
  if(ci->blocksizes[1]<ci->blocksizes[0])goto err_out;
  if(ci->blocksizes[1]>8192)goto err_out;

  if(oggpack_read(opb,1)!=1)goto err_out; /* EOP check */

  return(0);
 err_out:
  vorbis_info_clear(vi);
  return(OV_EBADHEADER);
}

static int _vorbis_unpack_comment(vorbis_comment *vc,oggpack_buffer *opb){
  int i;
  int vendorlen=oggpack_read(opb,32);
  if(vendorlen<0)goto err_out;
  if(vendorlen>opb->storage-8)goto err_out;
  vc->vendor=_ogg_calloc(vendorlen+1,1);
  _v_readstring(opb,vc->vendor,vendorlen);
  i=oggpack_read(opb,32);
  if(i<0)goto err_out;
  if(i>((opb->storage-oggpack_bytes(opb))>>2))goto err_out;
  vc->comments=i;
  vc->user_comments=_ogg_calloc(vc->comments+1,sizeof(*vc->user_comments));
  vc->comment_lengths=_ogg_calloc(vc->comments+1, sizeof(*vc->comment_lengths));

  for(i=0;i<vc->comments;i++){
    int len=oggpack_read(opb,32);
    if(len<0)goto err_out;
    if(len>opb->storage-oggpack_bytes(opb))goto err_out;
    vc->comment_lengths[i]=len;
    vc->user_comments[i]=_ogg_calloc(len+1,1);
    _v_readstring(opb,vc->user_comments[i],len);
  }
  if(oggpack_read(opb,1)!=1)goto err_out; /* EOP check */

  return(0);
 err_out:
  vorbis_comment_clear(vc);
  return(OV_EBADHEADER);
}

/* all of the real encoding details are here.  The modes, books,
   everything */
static int _vorbis_unpack_books(vorbis_info *vi,oggpack_buffer *opb){
  codec_setup_info     *ci=vi->codec_setup;
  int i;

  /* codebooks */
  ci->books=oggpack_read(opb,8)+1;
  if(ci->books<=0)goto err_out;
  for(i=0;i<ci->books;i++){
    ci->book_param[i]=vorbis_staticbook_unpack(opb);
    if(!ci->book_param[i])goto err_out;
  }

  /* time backend settings; hooks are unused */
  {
    int times=oggpack_read(opb,6)+1;
    if(times<=0)goto err_out;
    for(i=0;i<times;i++){
      int test=oggpack_read(opb,16);
      if(test<0 || test>=VI_TIMEB)goto err_out;
    }
  }

  /* floor backend settings */
  ci->floors=oggpack_read(opb,6)+1;
  if(ci->floors<=0)goto err_out;
  for(i=0;i<ci->floors;i++){
    ci->floor_type[i]=oggpack_read(opb,16);
    if(ci->floor_type[i]<0 || ci->floor_type[i]>=VI_FLOORB)goto err_out;
    ci->floor_param[i]=_floor_P[ci->floor_type[i]]->unpack(vi,opb);
    if(!ci->floor_param[i])goto err_out;
  }

  /* residue backend settings */
  ci->residues=oggpack_read(opb,6)+1;
  if(ci->residues<=0)goto err_out;
  for(i=0;i<ci->residues;i++){
    ci->residue_type[i]=oggpack_read(opb,16);
    if(ci->residue_type[i]<0 || ci->residue_type[i]>=VI_RESB)goto err_out;
    ci->residue_param[i]=_residue_P[ci->residue_type[i]]->unpack(vi,opb);
    if(!ci->residue_param[i])goto err_out;
  }

  /* map backend settings */
  ci->maps=oggpack_read(opb,6)+1;
  if(ci->maps<=0)goto err_out;
  for(i=0;i<ci->maps;i++){
    ci->map_type[i]=oggpack_read(opb,16);
    if(ci->map_type[i]<0 || ci->map_type[i]>=VI_MAPB)goto err_out;
    ci->map_param[i]=_mapping_P[ci->map_type[i]]->unpack(vi,opb);
    if(!ci->map_param[i])goto err_out;
  }

  /* mode settings */
  ci->modes=oggpack_read(opb,6)+1;
  if(ci->modes<=0)goto err_out;
  for(i=0;i<ci->modes;i++){
    ci->mode_param[i]=_ogg_calloc(1,sizeof(*ci->mode_param[i]));
    ci->mode_param[i]->blockflag=oggpack_read(opb,1);
    ci->mode_param[i]->windowtype=oggpack_read(opb,16);
    ci->mode_param[i]->transformtype=oggpack_read(opb,16);
    ci->mode_param[i]->mapping=oggpack_read(opb,8);

    if(ci->mode_param[i]->windowtype>=VI_WINDOWB)goto err_out;
    if(ci->mode_param[i]->transformtype>=VI_WINDOWB)goto err_out;
    if(ci->mode_param[i]->mapping>=ci->maps)goto err_out;
    if(ci->mode_param[i]->mapping<0)goto err_out;
  }

  if(oggpack_read(opb,1)!=1)goto err_out; /* top level EOP check */

  return(0);
 err_out:
  vorbis_info_clear(vi);
  return(OV_EBADHEADER);
}

/* Is this packet a vorbis ID header? */
int vorbis_synthesis_idheader(ogg_packet *op){
  oggpack_buffer opb;
  char buffer[6];

  if(op){
    oggpack_readinit(&opb,op->packet,op->bytes);

    if(!op->b_o_s)
      return(0); /* Not the initial packet */

    if(oggpack_read(&opb,8) != 1)
      return 0; /* not an ID header */

    memset(buffer,0,6);
    _v_readstring(&opb,buffer,6);
    if(memcmp(buffer,"vorbis",6))
      return 0; /* not vorbis */

    return 1;
  }

  return 0;
}

/* The Vorbis header is in three packets; the initial small packet in
   the first page that identifies basic parameters, a second packet
   with bitstream comments and a third packet that holds the
   codebook. */

int vorbis_synthesis_headerin(vorbis_info *vi,vorbis_comment *vc,ogg_packet *op){
  oggpack_buffer opb;

  if(op){
    oggpack_readinit(&opb,op->packet,op->bytes);

    /* Which of the three types of header is this? */
    /* Also verify header-ness, vorbis */
    {
      char buffer[6];
      int packtype=oggpack_read(&opb,8);
      memset(buffer,0,6);
      _v_readstring(&opb,buffer,6);
      if(memcmp(buffer,"vorbis",6)){
        /* not a vorbis header */
        return(OV_ENOTVORBIS);
      }
      switch(packtype){
      case 0x01: /* least significant *bit* is read first */
        if(!op->b_o_s){
          /* Not the initial packet */
          return(OV_EBADHEADER);
        }
        if(vi->rate!=0){
          /* previously initialized info header */
          return(OV_EBADHEADER);
        }

        return(_vorbis_unpack_info(vi,&opb));

      case 0x03: /* least significant *bit* is read first */
        if(vi->rate==0){
          /* um... we didn't get the initial header */
          return(OV_EBADHEADER);
        }
        if(vc->vendor!=NULL){
          /* previously initialized comment header */
          return(OV_EBADHEADER);
        }

        return(_vorbis_unpack_comment(vc,&opb));

      case 0x05: /* least significant *bit* is read first */
        if(vi->rate==0 || vc->vendor==NULL){
          /* um... we didn;t get the initial header or comments yet */
          return(OV_EBADHEADER);
        }
        if(vi->codec_setup==NULL){
          /* improperly initialized vorbis_info */
          return(OV_EFAULT);
        }
        if(((codec_setup_info *)vi->codec_setup)->books>0){
          /* previously initialized setup header */
          return(OV_EBADHEADER);
        }

        return(_vorbis_unpack_books(vi,&opb));

      default:
        /* Not a valid vorbis header type */
        return(OV_EBADHEADER);
        break;
      }
    }
  }
  return(OV_EBADHEADER);
}

/* pack side **********************************************************/

static int _vorbis_pack_info(oggpack_buffer *opb,vorbis_info *vi){
  codec_setup_info     *ci=vi->codec_setup;
  if(!ci||
     ci->blocksizes[0]<64||
     ci->blocksizes[1]<ci->blocksizes[0]){
    return(OV_EFAULT);
  }

  /* preamble */
  oggpack_write(opb,0x01,8);
  _v_writestring(opb,"vorbis", 6);

  /* basic information about the stream */
  oggpack_write(opb,0x00,32);
  oggpack_write(opb,vi->channels,8);
  oggpack_write(opb,vi->rate,32);

  oggpack_write(opb,vi->bitrate_upper,32);
  oggpack_write(opb,vi->bitrate_nominal,32);
  oggpack_write(opb,vi->bitrate_lower,32);

  oggpack_write(opb,ov_ilog(ci->blocksizes[0]-1),4);
  oggpack_write(opb,ov_ilog(ci->blocksizes[1]-1),4);
  oggpack_write(opb,1,1);

  return(0);
}

static int _vorbis_pack_comment(oggpack_buffer *opb,vorbis_comment *vc){
  int bytes = strlen(ENCODE_VENDOR_STRING);

  /* preamble */
  oggpack_write(opb,0x03,8);
  _v_writestring(opb,"vorbis", 6);

  /* vendor */
  oggpack_write(opb,bytes,32);
  _v_writestring(opb,ENCODE_VENDOR_STRING, bytes);

  /* comments */

  oggpack_write(opb,vc->comments,32);
  if(vc->comments){
    int i;
    for(i=0;i<vc->comments;i++){
      if(vc->user_comments[i]){
        oggpack_write(opb,vc->comment_lengths[i],32);
        _v_writestring(opb,vc->user_comments[i], vc->comment_lengths[i]);
      }else{
        oggpack_write(opb,0,32);
      }
    }
  }
  oggpack_write(opb,1,1);

  return(0);
}

static int _vorbis_pack_books(oggpack_buffer *opb,vorbis_info *vi){
  codec_setup_info     *ci=vi->codec_setup;
  int i;
  if(!ci)return(OV_EFAULT);

  oggpack_write(opb,0x05,8);
  _v_writestring(opb,"vorbis", 6);

  /* books */
  oggpack_write(opb,ci->books-1,8);
  for(i=0;i<ci->books;i++)
    if(vorbis_staticbook_pack(ci->book_param[i],opb))goto err_out;

  /* times; hook placeholders */
  oggpack_write(opb,0,6);
  oggpack_write(opb,0,16);

  /* floors */
  oggpack_write(opb,ci->floors-1,6);
  for(i=0;i<ci->floors;i++){
    oggpack_write(opb,ci->floor_type[i],16);
    if(_floor_P[ci->floor_type[i]]->pack)
      _floor_P[ci->floor_type[i]]->pack(ci->floor_param[i],opb);
    else
      goto err_out;
  }

  /* residues */
  oggpack_write(opb,ci->residues-1,6);
  for(i=0;i<ci->residues;i++){
    oggpack_write(opb,ci->residue_type[i],16);
    _residue_P[ci->residue_type[i]]->pack(ci->residue_param[i],opb);
  }

  /* maps */
  oggpack_write(opb,ci->maps-1,6);
  for(i=0;i<ci->maps;i++){
    oggpack_write(opb,ci->map_type[i],16);
    _mapping_P[ci->map_type[i]]->pack(vi,ci->map_param[i],opb);
  }

  /* modes */
  oggpack_write(opb,ci->modes-1,6);
  for(i=0;i<ci->modes;i++){
    oggpack_write(opb,ci->mode_param[i]->blockflag,1);
    oggpack_write(opb,ci->mode_param[i]->windowtype,16);
    oggpack_write(opb,ci->mode_param[i]->transformtype,16);
    oggpack_write(opb,ci->mode_param[i]->mapping,8);
  }
  oggpack_write(opb,1,1);

  return(0);
err_out:
  return(-1);
}

int vorbis_commentheader_out(vorbis_comment *vc,
                                          ogg_packet *op){

  oggpack_buffer opb;

  oggpack_writeinit(&opb);
  if(_vorbis_pack_comment(&opb,vc)){
    oggpack_writeclear(&opb);
    return OV_EIMPL;
  }

  op->packet = _ogg_malloc(oggpack_bytes(&opb));
  memcpy(op->packet, opb.buffer, oggpack_bytes(&opb));

  op->bytes=oggpack_bytes(&opb);
  op->b_o_s=0;
  op->e_o_s=0;
  op->granulepos=0;
  op->packetno=1;

  oggpack_writeclear(&opb);
  return 0;
}

int vorbis_analysis_headerout(vorbis_dsp_state *v,
                              vorbis_comment *vc,
                              ogg_packet *op,
                              ogg_packet *op_comm,
                              ogg_packet *op_code){
  int ret=OV_EIMPL;
  vorbis_info *vi=v->vi;
  oggpack_buffer opb;
  private_state *b=v->backend_state;

  if(!b||vi->channels<=0){
    ret=OV_EFAULT;
    goto err_out;
  }

  /* first header packet **********************************************/

  oggpack_writeinit(&opb);
  if(_vorbis_pack_info(&opb,vi))goto err_out;

  /* build the packet */
  if(b->header)_ogg_free(b->header);
  b->header=_ogg_malloc(oggpack_bytes(&opb));
  memcpy(b->header,opb.buffer,oggpack_bytes(&opb));
  op->packet=b->header;
  op->bytes=oggpack_bytes(&opb);
  op->b_o_s=1;
  op->e_o_s=0;
  op->granulepos=0;
  op->packetno=0;

  /* second header packet (comments) **********************************/

  oggpack_reset(&opb);
  if(_vorbis_pack_comment(&opb,vc))goto err_out;

  if(b->header1)_ogg_free(b->header1);
  b->header1=_ogg_malloc(oggpack_bytes(&opb));
  memcpy(b->header1,opb.buffer,oggpack_bytes(&opb));
  op_comm->packet=b->header1;
  op_comm->bytes=oggpack_bytes(&opb);
  op_comm->b_o_s=0;
  op_comm->e_o_s=0;
  op_comm->granulepos=0;
  op_comm->packetno=1;

  /* third header packet (modes/codebooks) ****************************/

  oggpack_reset(&opb);
  if(_vorbis_pack_books(&opb,vi))goto err_out;

  if(b->header2)_ogg_free(b->header2);
  b->header2=_ogg_malloc(oggpack_bytes(&opb));
  memcpy(b->header2,opb.buffer,oggpack_bytes(&opb));
  op_code->packet=b->header2;
  op_code->bytes=oggpack_bytes(&opb);
  op_code->b_o_s=0;
  op_code->e_o_s=0;
  op_code->granulepos=0;
  op_code->packetno=2;

  oggpack_writeclear(&opb);
  return(0);
 err_out:
  memset(op,0,sizeof(*op));
  memset(op_comm,0,sizeof(*op_comm));
  memset(op_code,0,sizeof(*op_code));

  if(b){
    oggpack_writeclear(&opb);
    if(b->header)_ogg_free(b->header);
    if(b->header1)_ogg_free(b->header1);
    if(b->header2)_ogg_free(b->header2);
    b->header=NULL;
    b->header1=NULL;
    b->header2=NULL;
  }
  return(ret);
}

double vorbis_granule_time(vorbis_dsp_state *v,ogg_int64_t granulepos){
  if(granulepos == -1) return -1;

  /* We're not guaranteed a 64 bit unsigned type everywhere, so we
     have to put the unsigned granpo in a signed type. */
  if(granulepos>=0){
    return((double)granulepos/v->vi->rate);
  }else{
    ogg_int64_t granuleoff=0xffffffff;
    granuleoff<<=31;
    granuleoff|=0x7ffffffff;
    return(((double)granulepos+2+granuleoff+granuleoff)/v->vi->rate);
  }
}

const char *vorbis_version_string(void){
  return GENERAL_VENDOR_STRING;
}