livoxGen/Proto1: Refine auto-detection vs heuristic logic

commonLibs/livoxProto1/device.cpp

@@ -81,7 +81,7 @@ Device::Device(const std::string &deviceIdentifier,
 	""),
 componentThread(componentThread),
 handshakeTimeoutMs(handshakeTimeoutMs), retryDelayMs(retryDelayMs),
-smoIp(smoIp), smoSubnetNbits(smoSubnetNbits),
+smoIp(smoIp), detectedSmoListeningIp(""), smoSubnetNbits(smoSubnetNbits),
 dataPort(dataPort), cmdPort(cmdPort), imuPort(imuPort),
 heartbeatFd(-1),
 heartbeatActive(false)
@@ -286,7 +286,8 @@ void Device::connectToKnownDeviceReq(
 	)
 {
 	// Create the connection request object to hold state and callbacks
-	auto request = std::make_shared<ConnectToKnownDeviceReq>(*this, std::move(callback));
+	auto request = std::make_shared<ConnectToKnownDeviceReq>(
+		*this, std::move(callback));
 
 	auto& protoState = livoxProto1::getProtoState();
 	if (!protoState.deviceManager)
@@ -314,6 +315,30 @@ void Device::connectToKnownDeviceReq(
 	// Use the IP address from the broadcast message
 	request->deviceIP = request->deviceInfo->ipAddr;
 
+	// Determine the final listening IP address
+	auto smoIpResult = request->device.getSmoIp(request->deviceIP);
+	if (!smoIpResult.has_value())
+	{
+		// Auto-detection failed, fail early
+		std::cerr << __func__ << ": Failed to detect SMO listening IP for "
+			<< "known device ("
+			<< request->device.discoveredDevice.deviceIdentifier << ")"
+			<< " @(" << request->deviceIP << ").\n";
+
+		request->callOriginalCallbackWithFailure();
+		return;
+	}
+
+	if (OptionParser::getOptions().verbose)
+	{
+		std::cout << __func__ << ": Detected SMO listening IP for known device "
+			<< request->device.discoveredDevice.deviceIdentifier
+			<< " @(" << request->deviceIP << ") is "
+			<< smoIpResult.value() << ". About to try to handshake.\n";
+	}
+
+	request->device.detectedSmoListeningIp = smoIpResult.value();
+
 	// Execute handshake with the known device using async method
 	request->device.executeHandshakeReq(
 		request->deviceIP,
@@ -358,6 +383,24 @@ void Device::connectByDeviceIdentifierReq(
 	Device::connectByDeviceIdentifierReqCbFn callback
 	)
 {
+	/**		EXPLANATION:
+	 * This method uses heuristic device IP construction from the serial number.
+	 * This requires smoIp to be provided because:
+	 * 1. We need the network prefix to generate a valid device IP address
+	 * 2. Without a target device IP, we cannot detect which interface faces the device
+	 * 3. Therefore, if smoIp is omitted, heuristic construction is impossible
+	 *
+	 * If smoIp is not provided, the driver must rely only on broadcast advertisements
+	 * from the device (handled by connectToKnownDeviceReq).
+	 */
+
+	// Check if smoIp is provided - required for heuristic construction
+	if (smoIp.empty())
+	{
+		callback(false, "", -1);
+		return;
+	}
+
 	// Create the connection request object to hold state and callbacks
 	auto request = std::make_shared<ConnectByDeviceIdentifierReq>(
 		*this, std::move(callback));
@@ -366,6 +409,16 @@ void Device::connectByDeviceIdentifierReq(
 	request->deviceIP = generateClientDeviceIpFromSerialNumber(
 		request->device.discoveredDevice.deviceIdentifier);
 
+	// For heuristic construction, always use the provided smoIp.
+	request->device.detectedSmoListeningIp = request->device.smoIp;
+
+	if (OptionParser::getOptions().verbose)
+	{
+		std::cout << __func__ << ": About to try to connect to device by "
+			<< "identifier (" << discoveredDevice.deviceIdentifier << ")"
+			<< " at IP (" << smoIp << ").\n";
+	}
+
 	// Execute handshake using async method
 	request->device.executeHandshakeReq(
 		request->deviceIP,
@@ -508,9 +561,9 @@ private:
 		/**		EXPLANATION:
 		 * Prepare handshake request.
 		 */
-		std::string smoIp = device.getSmoIp(deviceIP);
 		comms::HandshakeRequest handshakeReq(
-			smoIp, device.dataPort, device.cmdPort, device.imuPort);
+			device.detectedSmoListeningIp,
+			device.dataPort, device.cmdPort, device.imuPort);
 		handshakeReq.swapContentsToProtocolEndianness();
 		handshakeReq.header.setCrc16FromRawBytes();
 		handshakeReq.header.swapCrc16ToProtocolEndianness();
@@ -764,6 +817,14 @@ void Device::executeHandshakeReq(
 	auto request = std::make_shared<ExecuteHandshakeReq>(
 		*this, deviceIP, std::move(callback));
 
+	// Check if detectedSmoListeningIp is empty - this should not happen
+	if (detectedSmoListeningIp.empty())
+	{
+		// This should not happen as it should be set by the calling method
+		request->callOriginalCallbackWithFailure();
+		return;
+	}
+
 	try {
 		if (!request->setupSocket())
 		{
@@ -1143,25 +1204,42 @@ std::optional<std::string> Device::detectSmoIp(const std::string& deviceIP)
 	}
 }
 
-std::string Device::getSmoIp(const std::string& deviceIP)
+std::optional<std::string> Device::getSmoIp(const std::string& deviceIP)
 {
 	/**		EXPLANATION:
-	 * If smo-ip was provided, return it.
-	 * Otherwise, try to detect it based on the client device's IP address.
-	 * If detection failed, throw an exception.
+	 * This is only used when connecting to a device that's already known to
+	 * the broadcastListener.
+	 * It is NOT and SHOULD not be used when connecting by heuristic IP
+	 * construction using the client device's serial number.
+	 *
+	 * Determines the SMO listening IP address for this device.
+	 * If smoIp is provided, validate it against detected IP and return it.
+	 * If smoIp is empty, attempt auto-detection based on device IP.
+	 * Returns std::optional<std::string> - empty if detection fails.
 	 */
-	if (!smoIp.empty()) {
+	auto detectedIp = detectSmoIp(deviceIP);
+
+	if (!smoIp.empty())
+	{
+		// smoIp was provided, validate it against detected IP
+		if (detectedIp.has_value() && detectedIp.value() != smoIp)
+		{
+			// Print warning if provided smoIp doesn't match detected IP
+			std::cerr << "Warning: Provided smo-ip (" << smoIp 
+				<< ") doesn't match detected IP (" << detectedIp.value() 
+				<< ") for device " << discoveredDevice.deviceIdentifier
+				<< " @(" << deviceIP << ")"
+				<< ". Using provided smo-ip anyway." << std::endl;
+		}
 		return smoIp;
 	}
 
-	auto detectedIp = detectSmoIp(deviceIP);
 	if (detectedIp.has_value()) {
 		return detectedIp.value();
 	}
 
-	throw std::runtime_error(
-		std::string(__func__) + ": Failed to detect SMO IP address for device "
-		+ deviceIP + " with subnet mask /" + std::to_string(smoSubnetNbits));
+	// Auto-detection failed
+	return std::nullopt;
 }
 
 } // namespace livoxProto1

commonLibs/livoxProto1/device.h

@@ -73,6 +73,7 @@ public:
 	std::shared_ptr<smo::ComponentThread> componentThread;
 	int handshakeTimeoutMs, retryDelayMs;
 	std::string smoIp;
+	std::string detectedSmoListeningIp;
 	uint8_t smoSubnetNbits;
 	uint16_t dataPort, cmdPort, imuPort;
 
@@ -96,7 +97,7 @@ private:
 
 public:
 	// Utility methods
-	std::string getSmoIp(const std::string& deviceIP);
+	std::optional<std::string> getSmoIp(const std::string& deviceIP);
 
 	// Callback function type definitions for async methods
 	typedef std::function<void(bool success)> connectReqCbFn;

docs/livox-gen1-lidar-dap-spec.md

@@ -145,7 +145,23 @@ The `livoxProto1` provider accepts the following parameters:
 
 ## Device Discovery and Connection
 
-The specification uses a retry-based connection strategy:
+The specification uses a retry-based connection strategy with two different approaches:
+
+### Connection Methods
+
+**1. Broadcast-Based Connection (connectToKnownDeviceReq)**
+- Uses device IP addresses discovered from broadcast advertisements
+- **smo-ip parameter**: Optional - if omitted, driver auto-detects the appropriate interface
+- **smo-subnet-nbits parameter**: Optional - used for validation if smo-ip is provided
+- **When to use**: When devices are actively broadcasting their presence
+
+**2. Heuristic Connection (connectByDeviceIdentifierReq)**
+- Generates device IP addresses from serial numbers using network prefix
+- **smo-ip parameter**: **Required** - needed to determine network prefix for IP generation
+- **smo-subnet-nbits parameter**: **Required** - needed to calculate valid device IP addresses
+- **When to use**: When devices are not broadcasting or for initial setup
+
+### Connection Strategy
 
 1. **Initial Check**: Check if device is already known from broadcasts
 2. **Direct Connect**: Attempt direct connection based on calculated IP address

senseApis/livoxGen1/livoxGen1.cpp

@@ -176,8 +176,8 @@ extern "C" int livoxGen1_attachDeviceReq(
 	uint16_t dataPort = 56000;		// Default data port
 	uint16_t cmdPort = 56001;		// Default command port
 	uint16_t imuPort = 56002;		// Default IMU port
-	// Default: 10.42.0.1
-	std::string smoIp = "10.42.0.1";
+	// Default: empty string (will trigger IP auto-detection)
+	std::string smoIp = "";
 
 	// Parse optional integer parameters from provider params
 	for (const auto& param : desc->providerParams)