text: /********************************************************************
   *                                                                  *
   * 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 1994-2010             *
   * by the Xiph.Org Foundation http://www.xiph.org/                  *
   *                                                                  *
   ********************************************************************
  
   function: maintain the info structure, info <-> header packets
   last mod: $Id: info.c 19058 2014-01-22 18:03:15Z 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 1.3.4"
  #define ENCODE_VENDOR_STRING "Xiph.Org libVorbis I 20140122 (Turpakäräjiin)"
  
  /* 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){
    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;
    if(!ci)return(OV_EFAULT);
  
    /* 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);
          }
  
          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){
    codec_setup_info     *ci=vi->codec_setup;
    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(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){
      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 (vorbis/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;
  }
  