src/marnav-io/default_seatalk_reader.cpp

   1 #include <marnav-io/default_seatalk_reader.hpp>
   2
   3 /// @example simple_seatalk_nmea_converter.cpp
   4 /// This is a very simplistic conversion from SeaTalk messages to NMEA sentences.
   5 ///
   6 /// SeaTalk message are being read from a serial port, converted to a corresponding
   7 /// NMEA message, which is sent on another serial port.
   8 ///
   9 /// This example uses the marnav::io::default_seatalk_reader to read SeaTalk
  10 /// messages and \c boost.asio to send NMEA sentences.
  11
  12 namespace marnav
  13 {
  14 namespace io
  15 {
  16 default_seatalk_reader::default_seatalk_reader(std::unique_ptr<device> && dv)
  17         : seatalk_reader(std::move(dv))
  18         , message_received_(false)
  19 {
  20 }
  21
  22 /// Reads synchronously messages from the device.
  23 ///
  24 /// @param[out] data The received message.
  25 /// @retval true  Success.
  26 /// @retval false End of file.
  27 /// @exception std::runtime_error
  28 bool default_seatalk_reader::read_message(seatalk::raw & data)
  29 {
  30         // reads as long as the message is not complete.
  31         while (read()) {
  32                 // the message was received, return it and reset the 'semaphore'.
  33                 // please note: this works only in single threaded environment,
  34                 // since the 'semaphore' isn't really one.
  35                 if (message_received_) {
  36                         data = message_;
  37                         message_received_ = false;
  38                         return true;
  39                 }
  40         }
  41         return false;
  42 }
  43
  44 /// Processes the received message. Uses the data member 'message_received'
  45 /// as poor-mans semaphore to signal the receipt.
  46 ///
  47 /// After the reception, the message will be stored temporarily.
  48 void default_seatalk_reader::process_message(const seatalk::raw & msg)
  49 {
  50         message_ = msg;
  51         message_received_ = true;
  52 }
  53 }
  54 }