In file included from main.cpp:35:0:
buffered_reader.h: In member function 'int32_t BufferedReader::Read(char*, int32_t)':
buffered_reader.h:12:23: error: 'const int32_t PackageStream::package_len_' is private within this context
         this->stream->package_len_ = buffer_len;
                       ^~~~~~~~~~~~
main.cpp:29:19: note: declared private here
     const int32_t package_len_;
                   ^~~~~~~~~~~~
In file included from main.cpp:35:0:
buffered_reader.h:12:38: error: assignment of read-only member 'PackageStream::package_len_'
         this->stream->package_len_ = buffer_len;
                                      ^~~~~~~~~~