From 14e26f5c17b43ffbc3b2467d752386edf46db0af Mon Sep 17 00:00:00 2001
From: SChernykh <sergey.v.chernykh@gmail.com>
Date: Mon, 13 Sep 2021 19:11:59 +0200
Subject: [PATCH] Fix: always check before closing TCP handles

---
 src/json_rpc_request.cpp |  6 ++++--
 src/tcp_server.inl       | 15 ++++++++++++---
 2 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/src/json_rpc_request.cpp b/src/json_rpc_request.cpp
index 2a2cb4d..7ed54d2 100644
--- a/src/json_rpc_request.cpp
+++ b/src/json_rpc_request.cpp
@@ -216,8 +216,10 @@ void JSONRPCRequest::on_read(const char* data, size_t size)
 
 void JSONRPCRequest::close()
 {
-	uv_tcp_t* s = &m_socket;
-	uv_close(reinterpret_cast<uv_handle_t*>(s), on_close);
+	uv_handle_t* h = reinterpret_cast<uv_handle_t*>(&m_socket);
+	if (!uv_is_closing(h)) {
+		uv_close(h, on_close);
+	}
 }
 
 void JSONRPCRequest::on_close(uv_handle_t* handle)
diff --git a/src/tcp_server.inl b/src/tcp_server.inl
index 6ecc1b3..aa438b0 100644
--- a/src/tcp_server.inl
+++ b/src/tcp_server.inl
@@ -385,10 +385,16 @@ void TCPServer<READ_BUF_SIZE, WRITE_BUF_SIZE>::close_sockets(bool listen_sockets
 
 	if (listen_sockets) {
 		for (uv_tcp_t* s : m_listenSockets6) {
-			uv_close(reinterpret_cast<uv_handle_t*>(s), [](uv_handle_t* h) { delete reinterpret_cast<uv_tcp_t*>(h); });
+			uv_handle_t* h = reinterpret_cast<uv_handle_t*>(s);
+			if (!uv_is_closing(h)) {
+				uv_close(h, [](uv_handle_t* h) { delete reinterpret_cast<uv_tcp_t*>(h); });
+			}
 		}
 		for (uv_tcp_t* s : m_listenSockets) {
-			uv_close(reinterpret_cast<uv_handle_t*>(s), [](uv_handle_t* h) { delete reinterpret_cast<uv_tcp_t*>(h); });
+			uv_handle_t* h = reinterpret_cast<uv_handle_t*>(s);
+			if (!uv_is_closing(h)) {
+				uv_close(h, [](uv_handle_t* h) { delete reinterpret_cast<uv_tcp_t*>(h); });
+			}
 		}
 	}
 
@@ -621,7 +627,10 @@ void TCPServer<READ_BUF_SIZE, WRITE_BUF_SIZE>::on_connect(uv_connect_t* req, int
 			LOGWARN(5, "failed to connect to " << static_cast<char*>(client->m_addrString) << ", error " << uv_err_name(status));
 		}
 		server->on_connect_failed(client->m_isV6, client->m_addr, client->m_port);
-		uv_close(reinterpret_cast<uv_handle_t*>(&client->m_socket), nullptr);
+		uv_handle_t* h = reinterpret_cast<uv_handle_t*>(&client->m_socket);
+		if (!uv_is_closing(h)) {
+			uv_close(h, nullptr);
+		}
 		server->m_preallocatedClients.push_back(client);
 		return;
 	}