vorbis/lib/info.c

/********************************************************************
 *                                                                  *
 * 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 1994-2007             *
 * by the Xiph.Org Foundation http://www.xiph.org/                  *
 *                                                                  *
 ********************************************************************

 function: maintain the info structure, info <-> header packets
 last mod: $Id$

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

/* 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 1.2.3pre"
#define ENCODE_VENDOR_STRING "Xiph.Org libVorbis I 20090610"

/* helpers */
static int ilog2(unsigned int v){
  int ret=0;
  if(v)--v;
  while(v){
    ret++;
    v>>=1;
  }
  return(ret);
}

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){
  if(vc)
    memset(vc,0,sizeof(*vc));
}

void vorbis_comment_add(vorbis_comment *vc,const char *comment){
  if(vc && vc->comments>=0){
    void *ret =_ogg_realloc(vc->user_comments,
				   (vc->comments+2)*sizeof(*vc->user_comments));
    if(!ret)goto err;
    vc->user_comments=ret;

    ret=_ogg_realloc(vc->comment_lengths,
		     (vc->comments+2)*sizeof(*vc->comment_lengths));
    if(!ret)goto err;
    vc->comment_lengths=ret;
    vc->comment_lengths[vc->comments]=strlen(comment);

    ret=_ogg_malloc(vc->comment_lengths[vc->comments]+1);
    if(!ret)goto err;
    vc->user_comments[vc->comments]=ret;
    strcpy(vc->user_comments[vc->comments], comment);
    vc->comments++;
    vc->user_comments[vc->comments]=NULL;
  }
  return;
 err:
  vorbis_comment_clear(vc);
  vc->comments=OV_EHEAP;
}

void vorbis_comment_add_tag(vorbis_comment *vc, const char *tag, const char *contents){
  if(vc && vc->comments>=0 && tag && contents){
    char *comment=alloca(strlen(tag)+strlen(contents)+2); /* +2 for = and \0 */
    if(comment==NULL){
      vorbis_comment_clear(vc);
      vc->comments=OV_ESTACK;
    }else{
      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);

  if(fulltag){
    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++;
      }
    }
  }else{
    vorbis_comment_clear(vc);
    vc->comments=OV_ESTACK;
  }
  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);

  if(fulltag){
    strcpy(fulltag,tag);
    strcat(fulltag, "=");
    
    for(i=0;i<vc->comments;i++){
      if(!tagcompare(vc->user_comments[i], fulltag, taglen))
	count++;
    }
    
  }else{
    vorbis_comment_clear(vc);
    vc->comments=OV_ESTACK;
  }
  
  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));
  }
}

int vorbis_comment_check(vorbis_comment *vc){
  return (vc ? (vc->comments<0 ? vc->comments:0) : OV_EFAULT);
}

/* 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){
  if(vi && vi->version>=0){
    codec_setup_info *ci = vi->codec_setup;
    return ci ? ci->blocksizes[zo] : -1;
  }
  return -1;
}

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

void vorbis_info_clear(vorbis_info *vi){
  if(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));
  }
}

int vorbis_info_check(vorbis_info *vi){
  return(vi ? (vi->version>=0?0:vi->version) : OV_EFAULT);
}

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

static int _vorbis_unpack_info(vorbis_info *vi,oggpack_buffer *opb){
  if(vi && opb){
    codec_setup_info     *ci=vi->codec_setup;
    if(vi->version<0)return vi->version;
    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);
    vi->version=OV_EBADHEADER;
    return(vi->version=OV_EBADHEADER);
  }
  return(OV_EFAULT);
}

static int _vorbis_unpack_comment(vorbis_comment *vc,oggpack_buffer *opb){
  int i;
  int ret=OV_EBADHEADER;
  int vendorlen=oggpack_read(opb,32);
  if(vendorlen<0)goto err_out;
  if(vendorlen+8>opb->storage)goto err_out;
  vc->vendor=_ogg_calloc(vendorlen+1,1);
  if(!vc->vendor){
    ret=OV_EHEAP;
    goto err_out;
  }
  _v_readstring(opb,vc->vendor,vendorlen);
  i=oggpack_read(opb,32);
  if(i<0)goto err_out;
  if(4*i+oggpack_bytes(opb)>opb->storage)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));
  if(!vc->user_comments || !vc->comment_lengths){
    ret=OV_EHEAP;
    goto err_out;
  }

  for(i=0;i<vc->comments;i++){
    int len=oggpack_read(opb,32);
    if(len<0)goto err_out;
    if(len+oggpack_bytes(opb)>opb->storage)goto err_out;
    vc->comment_lengths[i]=len;
    vc->user_comments[i]=_ogg_calloc(len+1,1);
    if(!vc->user_comments[i]){
      ret=OV_EHEAP;
      goto err_out;
    }
    _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);
  vc->comments= -1;
  return(ret);
}

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

    if(vi->version<0)return(vi->version);
    if(!ci)return(OV_EFAULT);

    /* codebooks */
    ci->books=oggpack_read(opb,8)+1;
    /*ci->book_param=_ogg_calloc(ci->books,sizeof(*ci->book_param));*/
    for(i=0;i<ci->books;i++){
      ci->book_param[i]=_ogg_calloc(1,sizeof(*ci->book_param[i]));
      if(!ci->book_param[i]){
	ret=OV_EHEAP;
	goto err_out;
      }
      if((ret=vorbis_staticbook_unpack(opb,ci->book_param[i])))goto err_out;
    }
    
    /* time backend settings; hooks are unused */
    {
      int times=oggpack_read(opb,6)+1;
      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;
    /*ci->floor_type=_ogg_malloc(ci->floors*sizeof(*ci->floor_type));*/
    /*ci->floor_param=_ogg_calloc(ci->floors,sizeof(void *));*/
    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;
    /*ci->residue_type=_ogg_malloc(ci->residues*sizeof(*ci->residue_type));*/
    /*ci->residue_param=_ogg_calloc(ci->residues,sizeof(void *));*/
    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;
    /*ci->map_type=_ogg_malloc(ci->maps*sizeof(*ci->map_type));*/
    /*ci->map_param=_ogg_calloc(ci->maps,sizeof(void *));*/
    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;
    /*vi->mode_param=_ogg_calloc(vi->modes,sizeof(void *));*/
    for(i=0;i<ci->modes;i++){
      ci->mode_param[i]=_ogg_calloc(1,sizeof(*ci->mode_param[i]));
      if(!ci->mode_param[i]){
	ret=OV_EHEAP;
	goto err_out;
      }
      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(oggpack_read(opb,1)!=1)goto err_out; /* top level EOP check */
    
    return(0);
  err_out:
    if(vi->version<0)ret=vi->version; /* hack to return error state
					 from unpack functions called
					 through dispatch table */
    vorbis_info_clear(vi);
    vi->version=ret;
    return(ret);
  }
  return(OV_EFAULT);
}

/* 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);
        }

        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);
        }

        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){
  if(opb && vi){
    codec_setup_info     *ci=vi->codec_setup;
    if(vi->version<0)return(vi->version);
    if(!ci)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,ilog2(ci->blocksizes[0]),4);
    oggpack_write(opb,ilog2(ci->blocksizes[1]),4);
    oggpack_write(opb,1,1);
    return(oggpack_writecheck(opb)?OV_EHEAP:0);
  }
  return OV_EFAULT;
}

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(oggpack_writecheck(opb)?OV_EHEAP:0);
}
 
static int _vorbis_pack_books(oggpack_buffer *opb,vorbis_info *vi){
  int ret=OV_EFAULT;
  if(opb && vi){
    codec_setup_info     *ci=vi->codec_setup;
    int i;
    if(vi->version<0)return(vi->version);
    if(!ci)goto err_out;
    
    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((ret=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{
	ret=OV_EFAULT;
	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(oggpack_writecheck(opb)?OV_EHEAP:0);
  }
err_out:
  return(ret);
} 

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

  if(op){
    oggpack_buffer opb;
    int ret;

    oggpack_writeinit(&opb);
    if((ret=_vorbis_pack_comment(&opb,vc)))return(ret);
    
    op->packet = _ogg_malloc(oggpack_bytes(&opb));
    if(!op->packet){
      oggpack_writeclear(&opb);
      memset(op,0,sizeof(*op));
      return OV_EHEAP;
    }
    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;
  }
  return OV_EFAULT;
}

int vorbis_analysis_headerout(vorbis_dsp_state *v,
                              vorbis_comment *vc,
                              ogg_packet *op,
                              ogg_packet *op_comm,
                              ogg_packet *op_code){
  if(v){
    vorbis_info *vi=v->vi;
    oggpack_buffer opb;
    private_state *b=v->backend_state;
    int ret=0;
  
    if(!vc || !b || !op || !op_comm || !op_code) goto err_out;
    
    /* first header packet **********************************************/
    
    oggpack_writeinit(&opb);
    if((ret=_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));
    if(!b->header){
      ret=OV_EHEAP;
      goto err_out;
    }
    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((ret=_vorbis_pack_comment(&opb,vc)))goto err_out;
    if(b->header1)_ogg_free(b->header1);
    b->header1=_ogg_malloc(oggpack_bytes(&opb));
    if(!b->header1){
      ret=OV_EHEAP;
      goto err_out;
    }
    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((ret=_vorbis_pack_books(&opb,vi)))goto err_out;
    
    if(b->header2)_ogg_free(b->header2);
    b->header2=_ogg_malloc(oggpack_bytes(&opb));
    if(!b->header2){
      ret=OV_EHEAP;
      goto err_out;
    }
    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:
    oggpack_writeclear(&opb);
    memset(op,0,sizeof(*op));
    memset(op_comm,0,sizeof(*op_comm));
    memset(op_code,0,sizeof(*op_code));
    
    if(b){
      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);
  }

  return(OV_EFAULT);
}

double vorbis_granule_time(vorbis_dsp_state *v,ogg_int64_t granulepos){
  if(v && v->vi && v->vi->version>=0)
    if(granulepos>=0)
      return((double)granulepos/v->vi->rate);
  return(-1);
}

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