fsfw/datalinklayer/DataLinkLayer.cpp
2020-08-13 20:53:35 +02:00

140 lines
4.3 KiB
C++

#include "DataLinkLayer.h"
#include "../globalfunctions/CRC.h"
#include "../serviceinterface/ServiceInterfaceStream.h"
DataLinkLayer::DataLinkLayer(uint8_t* set_frame_buffer, ClcwIF* setClcw,
uint8_t set_start_sequence_length, uint16_t set_scid) :
spacecraftId(set_scid), frameBuffer(set_frame_buffer), clcw(setClcw), receivedDataLength(0), currentFrame(
NULL), startSequenceLength(set_start_sequence_length) {
//Nothing to do except from setting the values above.
}
DataLinkLayer::~DataLinkLayer() {
}
ReturnValue_t DataLinkLayer::frameDelimitingAndFillRemoval() {
if ((receivedDataLength - startSequenceLength) < FRAME_PRIMARY_HEADER_LENGTH) {
return SHORTER_THAN_HEADER;
}
//Removing start sequence.
//SHOULDDO: Not implemented here.
while ( *frameBuffer == START_SEQUENCE_PATTERN ) {
frameBuffer++;
}
TcTransferFrame frame_candidate(frameBuffer);
this->currentFrame = frame_candidate; //should work with shallow copy.
return RETURN_OK;
}
ReturnValue_t DataLinkLayer::frameValidationCheck() {
//Check TF_version number
if (this->currentFrame.getVersionNumber() != FRAME_VERSION_NUMBER_DEFAULT) {
return WRONG_TF_VERSION;
}
//Check SpaceCraft ID
if (this->currentFrame.getSpacecraftId() != this->spacecraftId) {
return WRONG_SPACECRAFT_ID;
}
//Check other header limitations:
if (!this->currentFrame.bypassFlagSet() && this->currentFrame.controlCommandFlagSet()) {
return NO_VALID_FRAME_TYPE;
}
//- Spares are zero
if (!this->currentFrame.spareIsZero()) {
return NO_VALID_FRAME_TYPE;
}
//Compare detected frame length with the one in the header
uint16_t length = currentFrame.getFullSize();
if (length > receivedDataLength) {
//Frame is too long or just right
// error << "frameValidationCheck: Too short.";
// currentFrame.print();
return TOO_SHORT;
}
if (USE_CRC) {
return this->frameCheckCRC();
}
return RETURN_OK;
}
ReturnValue_t DataLinkLayer::frameCheckCRC() {
uint16_t checkValue = CRC::crc16ccitt(this->currentFrame.getFullFrame(),
this->currentFrame.getFullSize());
if (checkValue == 0) {
return RETURN_OK;
} else {
return CRC_FAILED;
}
}
ReturnValue_t DataLinkLayer::allFramesReception() {
ReturnValue_t status = this->frameDelimitingAndFillRemoval();
if (status != RETURN_OK) {
return status;
}
return this->frameValidationCheck();
}
ReturnValue_t DataLinkLayer::masterChannelDemultiplexing() {
//Nothing to do at present. Ideally, there would be a map of MCID's identifying which MC to use.
return virtualChannelDemultiplexing();
}
ReturnValue_t DataLinkLayer::virtualChannelDemultiplexing() {
uint8_t vcId = currentFrame.getVirtualChannelId();
virtualChannelIterator iter = virtualChannels.find(vcId);
if (iter == virtualChannels.end()) {
//Do not report because passive board will get this error all the time.
return RETURN_OK;
} else {
return (iter->second)->frameAcceptanceAndReportingMechanism(&currentFrame, clcw);
}
}
ReturnValue_t DataLinkLayer::processFrame(uint16_t length) {
receivedDataLength = length;
ReturnValue_t status = allFramesReception();
if (status != RETURN_OK) {
sif::error << "DataLinkLayer::processFrame: frame reception failed. "
"Error code: " << std::hex << status << std::dec << std::endl;
// currentFrame.print();
return status;
} else {
return masterChannelDemultiplexing();
}
}
ReturnValue_t DataLinkLayer::addVirtualChannel(uint8_t virtualChannelId,
VirtualChannelReceptionIF* object) {
std::pair<virtualChannelIterator, bool> returnValue = virtualChannels.insert(
std::pair<uint8_t, VirtualChannelReceptionIF*>(virtualChannelId, object));
if (returnValue.second == true) {
return RETURN_OK;
} else {
return RETURN_FAILED;
}
}
ReturnValue_t DataLinkLayer::initialize() {
ReturnValue_t returnValue = RETURN_FAILED;
//Set Virtual Channel ID to first virtual channel instance in this DataLinkLayer instance to avoid faulty information (e.g. 0) in the VCID.
if ( virtualChannels.begin() != virtualChannels.end() ) {
clcw->setVirtualChannel( virtualChannels.begin()->second->getChannelId() );
} else {
sif::error << "DataLinkLayer::initialize: No VC assigned to this DLL instance! " << std::endl;
return RETURN_FAILED;
}
for (virtualChannelIterator iterator = virtualChannels.begin();
iterator != virtualChannels.end(); iterator++) {
returnValue = iterator->second->initialize();
if (returnValue != RETURN_OK)
break;
}
return returnValue;
}