Function DetectTextEncoding

Libraries/unrar/filestr.cpp:151–166

RAR_CHARSET DetectTextEncoding(const byte *Data,size_t DataSize)
{
  if (DataSize>3 && Data[0]==0xef && Data[1]==0xbb && Data[2]==0xbf &&
      IsTextUtf8(Data+3,DataSize-3))
    return RCH_UTF8;

  bool LittleEndian=DataSize>2 && Data[0]==255 && Data[1]==254;
  bool BigEndian=DataSize>2 && Data[0]==254 && Data[1]==255;

  if (LittleEndian || BigEndian)  
    for (size_t I=LittleEndian ? 3 : 2;I<DataSize;I+=2)
      if (Data[I]<32 && Data[I]!='\r' && Data[I]!='\n')
        return RCH_UNICODE; // High byte in UTF-16 char is found.

  return RCH_DEFAULT;
}