bool ProxySession::Transfer(FileDesc& src, FileDesc& dest, IParser& parser, std::error_code &ec)
{
// until we're using an actual plugin, just read and write to a local buffer
auto inBuff = parser.GetWriteSlice();
auto numRead = read(src, inBuff, inBuff.Size());
if(numRead < 0) {
ec = std::error_code(errno, std::system_category());
return false;
}
if(numRead == 0) {
ec = Error::END_OF_FILE;
return false;
}
if(m_config.observeOnly)
{
// in observe only mode we just write the data we read immediately
// there is no guarantee that the parser doesn't modify the buffer
this->WriteAll(dest, RSlice(inBuff, numRead), ec);
// regardless of if there is any error or not, we feed the parser
// but ignore whatever it outputs
parser.Parse(numRead);
}
else
{
// now notify the parser that we wrote some data into its input buffer
if(parser.Parse(numRead))
{
// if the parser didn't reject it, pass output anything the parser kicked back
this->WriteOutputTo(dest, ec);
}
else
{
ec = Error::PARSER_REJECT;
}
}
// always clear any unwritten slices due to error or explicit parser rejection
this->m_output_vec.clear();
return ec.value();
}
void LinkLayerParser::TransferUserData()
{
uint32_t len = header.GetLength() - LPDU_MIN_LENGTH;
LinkFrame::ReadUserData(buffer.ReadBuffer() + LPDU_HEADER_SIZE, rxBuffer, len);
userData = RSlice(rxBuffer, len);
}