Bug:BcastListener: Add SpinLock for races around stop()

commonLibs/livoxProto1/broadcastListener.cpp

@@ -1,5 +1,6 @@
 #include <algorithm>
 #include <iostream>
+#include <functional>
 #include <opts.h>
 #include <componentThread.h>
 #include "broadcastListener.h"
@@ -54,7 +55,6 @@ void BroadcastListener::broadcastMsgInd(
 		return;
 	}
 
-
 	// Use placement new to construct BroadcastMessage in the buffer
 	BroadcastMessage* msg = new (bcastMsgRecvBuffer) BroadcastMessage;
 
@@ -94,6 +94,8 @@ void BroadcastListener::broadcastMsgInd(
 		reinterpret_cast<const char*>(msg->broadcast_code));
 
 	// Early return if device already exists
+	smo::SpinLock::Guard lock(isListeningLock);
+
 	if (deviceExists(broadcastCode))
 	{
 		// Device already exists, just log the update
@@ -103,21 +105,23 @@ void BroadcastListener::broadcastMsgInd(
 				<< ": Received broadcast from known device: "
 				<< broadcastCode << " at " << senderIP << "\n";
 		}
-		return;
+	}
+	else
+	{
+		// Create new DiscoveredDevice using conversion constructor
+		auto device = std::make_shared<DiscoveredDevice>(*msg, senderIP);
+		discoveredDevices.push_back(device);
+		// Output device information using stringify
+		std::cout << __func__ << ": Discovered new Livox device: "
+			<< device->stringify() << "\n";
 	}
 
-	// Create new DiscoveredDevice using conversion constructor
+	startReceive();
-	auto device = std::make_shared<DiscoveredDevice>(*msg, senderIP);
-	discoveredDevices.push_back(device);
-
-	// Output device information using stringify
-	std::cout << __func__ << ": Discovered new Livox device: "
-		<< device->stringify() << "\n";
 }
 
 void BroadcastListener::start(void)
 {
-	if (isListening.load()) { return; }
+	if (isListening) { return; }
 
 	try
 	{
@@ -132,7 +136,7 @@ void BroadcastListener::start(void)
 		socket.open(boost::asio::ip::udp::v4());
 		socket.bind(listeningEndpoint);
 
-		isListening.store(true);
+		isListening = true;
 		// Start the first async receive operation
 		startReceive();
 		std::cout << __func__ << ": BroadcastListener started on port "
@@ -140,7 +144,7 @@ void BroadcastListener::start(void)
 	}
 	catch (const boost::system::system_error& e)
 	{
-		isListening.store(false);
+		isListening = false;
 		std::cerr << __func__ << ": Failed to start BroadcastListener: "
 			<< e.what() << std::endl;
 		throw;
@@ -149,27 +153,25 @@ void BroadcastListener::start(void)
 
 void BroadcastListener::startReceive(void)
 {
-	if (!isListening.load()) { return; }
+	if (!isListening) { return; }
 
 	socket.async_receive_from(
 		boost::asio::buffer(bcastMsgRecvBuffer, sizeof(bcastMsgRecvBuffer)),
 		senderEndpoint,
-		[this](const boost::system::error_code& ec, std::size_t bytes_received)
+		std::bind(
-		{
+			&BroadcastListener::broadcastMsgInd, this,
-			broadcastMsgInd(ec, bytes_received);
+			std::placeholders::_1, std::placeholders::_2)
-
-			// Continue listening for the next packet
-			if (isListening.load())
-				{ startReceive(); }
-		}
 	);
 }
 
 void BroadcastListener::stop(void)
 {
-	if (!isListening.load()) { return; }
+	{
+		smo::SpinLock::Guard lock(isListeningLock);
+		if (!isListening) { return; }
 
-	isListening.store(false);
+		isListening = false;
+	}
 
 	try
 	{

commonLibs/livoxProto1/broadcastListener.h

@@ -8,6 +8,7 @@
 #include <atomic>
 #include <boost/asio/ip/udp.hpp>
 #include <user/senseApiDesc.h>
+#include <spinLock.h>
 #include "device.h"
 
 namespace livoxProto1 {
@@ -67,7 +68,8 @@ private:
 
 	boost::asio::ip::udp::socket socket;
 	boost::asio::ip::udp::endpoint listeningEndpoint, senderEndpoint;
-	std::atomic<bool> isListening;
+	smo::SpinLock isListeningLock;
+	bool isListening;
 
 	uint8_t bcastMsgRecvBuffer[UDP_BCAST_MSG_BUFFER_NBYTES];
 };