libicsneo/communication/packet/spipacket.cpp

83 lines
3.4 KiB
C++

#include "icsneo/communication/packet/spipacket.h"
#include "icsneo/communication/command.h"
#include <cstring>
#include <vector>
using namespace icsneo;
static size_t SPISubHeaderLength = 5u;
std::shared_ptr<Message> HardwareSPIPacket::DecodeToMessage(const std::vector<uint8_t>& bytestream) {
if(bytestream.size() < sizeof(HardwareSPIPacket)) {
return nullptr;
}
const HardwareSPIPacket* packet = (const HardwareSPIPacket*)bytestream.data();
size_t totalPackedLength = static_cast<size_t>(bytestream.size()) - sizeof(HardwareSPIPacket); // First 28 bytes are message header.
if(totalPackedLength < SPISubHeaderLength) {
return nullptr;
}
const uint8_t* bytes = bytestream.data() + sizeof(HardwareSPIPacket);
std::shared_ptr<SPIMessage> msg = std::make_shared<SPIMessage>();
msg->direction = static_cast<SPIMessage::Direction>(bytes[0]);
msg->address = *reinterpret_cast<const uint16_t*>(&bytes[1]);
msg->mms = bytes[3];
msg->stats = packet->stats;
msg->timestamp = packet->timestamp.TS;
size_t numWords = (totalPackedLength - SPISubHeaderLength) / 4;
msg->payload.reserve(numWords);
for(size_t offset = SPISubHeaderLength; offset < totalPackedLength; offset += 4) {
msg->payload.push_back(*reinterpret_cast<const uint32_t*>(bytes + offset));
}
return msg;
}
bool HardwareSPIPacket::EncodeFromMessage(const SPIMessage& message, std::vector<uint8_t>& bytestream, const device_eventhandler_t& /*report*/) {
// Payload length is everything excluding cmdHeader (note at the beginning there is an offset of 2)
uint16_t payloadLength = static_cast<uint16_t>(
2 +
sizeof(HardwareSPIPacket) +
SPISubHeaderLength +
message.payload.size() * sizeof(uint32_t)
);
if(payloadLength % 2) {
// Pad payload to even number
payloadLength++;
}
// +1 for AA, another +1 for firmware nuance
uint16_t fullSize = 1 + sizeof(ExtendedCommandHeader) + payloadLength + 1;
uint16_t unwrappedSize = sizeof(ExtendedCommandHeader) + payloadLength; // fullSize without AA and firmware nuance
bytestream.resize(unwrappedSize, 0);
uint32_t offset = 0;
auto* cmdHeader = reinterpret_cast<ExtendedCommandHeader*>(bytestream.data() + offset);
cmdHeader->netid = static_cast<uint8_t>(Network::NetID::Main51);
cmdHeader->fullLength = fullSize;
cmdHeader->command = static_cast<uint8_t>(Command::Extended);
cmdHeader->extendedCommand = static_cast<uint16_t>(ExtendedCommand::TransmitCoreminiMessage);
cmdHeader->payloadLength = payloadLength;
offset += sizeof(ExtendedCommandHeader) + 2; // Offset of 2 between header and packet
auto* packet = reinterpret_cast<HardwareSPIPacket*>(bytestream.data() + offset);
packet->header.frameLength = static_cast<uint16_t>(SPISubHeaderLength + message.payload.size() * sizeof(uint32_t));
packet->networkID = static_cast<uint16_t>(message.network.getNetID());
packet->length = packet->header.frameLength;
packet->timestamp.IsExtended = 1;
offset += sizeof(HardwareSPIPacket);
// Write the sub header details
bytestream[offset++] = static_cast<uint8_t>(message.direction);
bytestream[offset++] = static_cast<uint8_t>(message.address & 0xFF);
bytestream[offset++] = static_cast<uint8_t>((message.address >> 8) & 0xFF);
bytestream[offset++] = static_cast<uint8_t>(message.mms);
bytestream[offset++] = static_cast<uint8_t>(message.payload.size());
// Write the words
for(uint32_t word : message.payload) {
*reinterpret_cast<uint32_t*>(bytestream.data() + offset) = word;
offset += sizeof(uint32_t);
}
return true;
}