Method decodeSymbol1

Libraries/unrar/model.cpp:412–454

inline bool RARPPM_CONTEXT::decodeSymbol1(ModelPPM *Model)
{
  Model->Coder.SubRange.scale=U.SummFreq;
  RARPPM_STATE* p=U.Stats;
  int i, HiCnt;
  int count=Model->Coder.GetCurrentCount();
  if (count>=(int)Model->Coder.SubRange.scale)
    return(false);
  if (count < (HiCnt=p->Freq)) 
  {
    Model->PrevSuccess=(2*(Model->Coder.SubRange.HighCount=HiCnt) > Model->Coder.SubRange.scale);
    Model->RunLength += Model->PrevSuccess;
    (Model->FoundState=p)->Freq=(HiCnt += 4);
    U.SummFreq += 4;
    if (HiCnt > MAX_FREQ)
      rescale(Model);
    Model->Coder.SubRange.LowCount=0;
    return(true);
  }
  else
    if (Model->FoundState==NULL)
      return(false);
  Model->PrevSuccess=0;
  i=NumStats-1;
  while ((HiCnt += (++p)->Freq) <= count)
    if (--i == 0) 
    {
      Model->HiBitsFlag=Model->HB2Flag[Model->FoundState->Symbol];
      Model->Coder.SubRange.LowCount=HiCnt;
      Model->CharMask[p->Symbol]=Model->EscCount;
      i=(Model->NumMasked=NumStats)-1;
      Model->FoundState=NULL;
      do 
      { 
        Model->CharMask[(--p)->Symbol]=Model->EscCount; 
      } while ( --i );
      Model->Coder.SubRange.HighCount=Model->Coder.SubRange.scale;
      return(true);
    }
  Model->Coder.SubRange.LowCount=(Model->Coder.SubRange.HighCount=HiCnt)-p->Freq;
  update1(Model,p);
  return(true);
}


inline void RARPPM_CONTEXT::update2(ModelPPM *Model,RARPPM_STATE* p)