From 81da1cdb26227d252abb93071b158348e0b8f144 Mon Sep 17 00:00:00 2001
From: "Alexander A. Klimov" <alexander.klimov@icinga.com>
Date: Wed, 7 Feb 2024 13:46:13 +0100
Subject: [PATCH] JsonRpcConnection#Disconnect(): spawn coroutine only if
 necessary

by checking the now atomic #m_ShuttingDown outside of it.
---
 lib/remote/jsonrpcconnection.cpp | 12 +++++-------
 lib/remote/jsonrpcconnection.hpp |  3 ++-
 2 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/lib/remote/jsonrpcconnection.cpp b/lib/remote/jsonrpcconnection.cpp
index 3bae3cafd..c86d59eb0 100644
--- a/lib/remote/jsonrpcconnection.cpp
+++ b/lib/remote/jsonrpcconnection.cpp
@@ -190,12 +190,10 @@ void JsonRpcConnection::Disconnect()
 {
 	namespace asio = boost::asio;
 
-	JsonRpcConnection::Ptr keepAlive (this);
-
-	IoEngine::SpawnCoroutine(m_IoStrand, [this, keepAlive](asio::yield_context yc) {
-		if (!m_ShuttingDown) {
-			m_ShuttingDown = true;
+	if (!m_ShuttingDown.exchange(true)) {
+		JsonRpcConnection::Ptr keepAlive (this);
 
+		IoEngine::SpawnCoroutine(m_IoStrand, [this, keepAlive](asio::yield_context yc) {
 			Log(LogWarning, "JsonRpcConnection")
 				<< "API client disconnected for identity '" << m_Identity << "'";
 
@@ -243,8 +241,8 @@ void JsonRpcConnection::Disconnect()
 			shutdownTimeout->Cancel();
 
 			m_Stream->lowest_layer().shutdown(m_Stream->lowest_layer().shutdown_both, ec);
-		}
-	});
+		});
+	}
 }
 
 void JsonRpcConnection::MessageHandler(const String& jsonString)
diff --git a/lib/remote/jsonrpcconnection.hpp b/lib/remote/jsonrpcconnection.hpp
index 591ddcb1f..3515573bb 100644
--- a/lib/remote/jsonrpcconnection.hpp
+++ b/lib/remote/jsonrpcconnection.hpp
@@ -5,6 +5,7 @@
 
 #include "remote/i2-remote.hpp"
 #include "remote/endpoint.hpp"
+#include "base/atomic.hpp"
 #include "base/io-engine.hpp"
 #include "base/tlsstream.hpp"
 #include "base/timer.hpp"
@@ -77,7 +78,7 @@ private:
 	std::vector<String> m_OutgoingMessagesQueue;
 	AsioConditionVariable m_OutgoingMessagesQueued;
 	AsioConditionVariable m_WriterDone;
-	bool m_ShuttingDown;
+	Atomic<bool> m_ShuttingDown;
 	boost::asio::deadline_timer m_CheckLivenessTimer, m_HeartbeatTimer;
 
 	JsonRpcConnection(const String& identity, bool authenticated, const Shared<AsioTlsStream>::Ptr& stream, ConnectionRole role, boost::asio::io_context& io);