LiveData: Initial implementation

Add support for live data subscription via Device::subscribeLiveData() and
Device::unsubscribeLiveData(). The live data API can be used to subscribe to
individual "signals", a full list of which can be found in LiveDataValueType.

include/icsneo/communication/livedata.h

@@ -0,0 +1,146 @@
+#ifndef __LIVEDATA_H__
+#define __LIVEDATA_H__
+#ifdef __cplusplus
+
+#include <cstdint>
+#include <vector>
+#include <memory>
+#include "icsneo/communication/command.h"
+#include "icsneo/api/eventmanager.h"
+
+namespace icsneo {
+
+typedef uint32_t LiveDataHandle;
+static constexpr size_t MAX_LIVE_DATA_ENTRIES = 20;
+
+enum class LiveDataCommand : uint32_t {
+	STATUS = 0,
+	SUBSCRIBE,
+	UNSUBSCRIBE,
+	RESPONSE,
+	CLEAR_ALL,
+};
+
+enum class LiveDataStatus : uint32_t {
+	SUCCESS = 0,
+	ERR_UNKNOWN_COMMAND,
+	ERR_HANDLE,
+	ERR_DUPLICATE,
+	ERR_FULL
+};
+
+enum LiveDataObjectType : uint16_t {
+	MISC = 8,
+	SNA = UINT16_MAX,
+};
+
+enum class LiveDataValueType : uint32_t {
+	GPS_LATITUDE = 2,
+	GPS_LONGITUDE,
+	GPS_ALTITUDE,
+	GPS_SPEED,
+	GPS_VALID,
+	GPS_ENABLE = 62,
+	GPS_ACCURACY = 120,
+	GPS_BEARING = 121,
+	GPS_TIME = 122,
+	GPS_TIME_VALID = 123,
+};
+
+inline std::ostream& operator<<(std::ostream& os, const LiveDataCommand cmd) {
+	switch (cmd) {
+		case LiveDataCommand::STATUS: return os << "Status";
+		case LiveDataCommand::SUBSCRIBE: return os << "Subscribe";
+		case LiveDataCommand::UNSUBSCRIBE: return os << "Unsubscribe";
+		case LiveDataCommand::RESPONSE: return os << "Response";
+	}
+	return os;
+}
+
+inline std::ostream& operator<<(std::ostream& os, const LiveDataStatus cmd) {
+	switch (cmd) {
+		case LiveDataStatus::SUCCESS: return os << "Success";
+		case LiveDataStatus::ERR_UNKNOWN_COMMAND: return os << "Error: Unknown Command";
+		case LiveDataStatus::ERR_HANDLE: return os << "Error: Handle";
+		case LiveDataStatus::ERR_DUPLICATE: return os << "Error: Duplicate";
+		case LiveDataStatus::ERR_FULL: return os << "Error: Argument limit reached";
+	}
+	return os;
+}
+
+inline std::ostream& operator<<(std::ostream& os, const LiveDataValueType cmd) {
+	switch (cmd) {
+		case LiveDataValueType::GPS_LATITUDE: return os << "GPS Latitude";
+		case LiveDataValueType::GPS_LONGITUDE: return os << "GPS Longitude";
+		case LiveDataValueType::GPS_ALTITUDE: return os << "GPS Altitude";
+		case LiveDataValueType::GPS_SPEED: return os << "GPS Speed";
+		case LiveDataValueType::GPS_VALID: return os << "GPS Valid";
+		case LiveDataValueType::GPS_ENABLE: return os << "GPS Enabled";
+		case LiveDataValueType::GPS_ACCURACY: return os << "GPS Accuracy";
+		case LiveDataValueType::GPS_BEARING: return os << "GPS Bearing";
+		case LiveDataValueType::GPS_TIME: return os << "GPS Time";
+		case LiveDataValueType::GPS_TIME_VALID: return os << "GPS Time Valid";
+	}
+	return os;
+}
+
+#pragma pack(push,2)
+struct LiveDataHeader {
+	uint32_t version; // See LiveDataVersion
+	uint32_t cmd;
+	uint32_t handle;
+};
+
+struct LiveDataArgument {
+	LiveDataObjectType objectType;
+	uint32_t objectIndex;
+	uint32_t signalIndex;
+	LiveDataValueType valueType;
+};
+
+struct LiveDataValueHeader {
+	uint16_t length; // Number of bytes to follow header
+	uint8_t reserved[2];
+};
+
+typedef struct
+{
+	LiveDataValueHeader header;
+	int64_t value;
+} LiveDataValue;
+
+struct LiveDataValueResponse : public LiveDataHeader {
+	uint32_t numArgs;
+	LiveDataValue values[1];
+};
+
+struct LiveDataStatusResponse : public LiveDataHeader {
+	LiveDataCommand requestedCommand;
+	LiveDataStatus status;
+};
+
+struct LiveDataSubscribe : public LiveDataHeader {
+	uint32_t numArgs;
+	uint32_t freqMs;
+	uint32_t expireMs;
+	LiveDataArgument args[1];
+};
+
+struct ExtResponseHeader {
+	ExtendedCommand command;
+	uint16_t length;
+};
+#pragma pack(pop)
+
+namespace LiveDataUtil
+{
+
+LiveDataHandle getNewHandle();
+double liveDataValueToDouble(const LiveDataValue& val);
+static constexpr uint32_t LiveDataVersion = 1;
+
+} // namespace LiveDataUtil
+} // namespace icsneo
+
+#endif // _cplusplus
+#endif // __LIVEDATA_H__