Re-work MPSoC handler module

linux/payload/MpsocCommunication.cpp

@@ -0,0 +1,75 @@
+#include "MpsocCommunication.h"
+
+#include "fsfw/globalfunctions/CRC.h"
+#include "fsfw/returnvalues/returnvalue.h"
+#include "fsfw/tmtcpacket/ccsds/SpacePacketReader.h"
+#include "fsfw/tmtcpacket/ccsds/header.h"
+#include "linux/payload/plocMpsocHelpers.h"
+#include "unistd.h"
+
+MpsocCommunication::MpsocCommunication(object_id_t objectId, SerialConfig cfg)
+    : SystemObject(objectId), readRingBuf(4096, true), helper(cfg) {}
+
+ReturnValue_t MpsocCommunication::initialize() { return helper.initialize(); }
+
+ReturnValue_t MpsocCommunication::send(const uint8_t* data, size_t dataLen) {
+  if (MPSOC_LOW_LEVEL_TX_WIRETAPPING) {
+    sif::debug << "SEND MPSOC packet with size " << dataLen << std::endl;
+  }
+  return helper.send(data, dataLen);
+}
+
+ReturnValue_t MpsocCommunication::parseAndRetrieveNextPacket() {
+  // We do not have a data link layer, so this whole thing is a mess in any case..
+  // But basically, we try to parse space packets from the internal ring buffer and trasnfer
+  // them to the higher level device handler. The CRC check is performed here as well, with
+  // few other ways to detect if we even have a valid packet.
+  size_t availableReadData = readRingBuf.getAvailableReadData();
+  // Minimum valid size for a space packet header.
+  if (availableReadData < ccsds::HEADER_LEN + 1) {
+    return returnvalue::OK;
+  }
+  readRingBuf.readData(readBuf, availableReadData);
+  spReader.setReadOnlyData(readBuf, sizeof(readBuf));
+  auto res = spReader.checkSize();
+  if (res != returnvalue::OK) {
+    return res;
+  }
+  // The packet might be garbage, with no way to recover without a data link layer.
+  if (spReader.getFullPacketLen() > 4096) {
+    readRingBuf.clear();
+    // TODO: Maybe we should also clear the serial input buffer in Linux?
+    return FAULTY_PACKET_SIZE;
+  }
+  if (availableReadData < spReader.getFullPacketLen()) {
+    // Might be split packet where the rest still has to be read.
+    return returnvalue::OK;
+  }
+  if (CRC::crc16ccitt(readBuf, spReader.getFullPacketLen()) != 0) {
+    // Possibly invalid packet. We can not even trust the detected packet length.
+    // Just clear the whole read buffer as well.
+    readRingBuf.clear();
+    triggerEvent(mpsoc::CRC_FAILURE);
+    return CRC_CHECK_FAILED;
+  }
+  readRingBuf.deleteData(spReader.getFullPacketLen());
+  return PACKET_RECEIVED;
+}
+
+ReturnValue_t MpsocCommunication::readSerialInterface() {
+  int bytesRead = read(helper.rawFd(), readBuf, sizeof(readBuf));
+  if (bytesRead < 0) {
+    return returnvalue::FAILED;
+  }
+  if (bytesRead > 0) {
+    if (MPSOC_LOW_LEVEL_RX_WIRETAPPING) {
+      sif::debug << "Read " << bytesRead << " bytes on the MPSoC interface" << std::endl;
+    }
+    return readRingBuf.writeData(readBuf, bytesRead);
+  }
+  return returnvalue::OK;
+}
+
+const SpacePacketReader& MpsocCommunication::getSpReader() const { return spReader; }
+
+SerialCommunicationHelper& MpsocCommunication::getComHelper() { return helper; }