event/net/ConnectSocket: use class TimeoutError in OnSocketConnectTimeout()

Author: MaxKellermann

src/event/net/ConnectSocket.cxx

@@ -7,6 +7,7 @@
 #include "net/SocketAddress.hxx"
 #include "net/AddressInfo.hxx"
 #include "net/SocketError.hxx"
+#include "net/TimeoutError.hxx"
 
 #include <cassert>
 #include <stdexcept>
@@ -15,7 +16,7 @@ void
 ConnectSocketHandler::OnSocketConnectTimeout() noexcept
 {
 	/* default implementation falls back to OnSocketConnectError() */
-	OnSocketConnectError(std::make_exception_ptr(std::runtime_error("Connect timeout")));
+	OnSocketConnectError(std::make_exception_ptr(TimeoutError{"Connect timeout"}));
 }
 
 ConnectSocket::ConnectSocket(EventLoop &_event_loop,

src/net/TimeoutError.hxx

@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: BSD-2-Clause
+// Copyright CM4all GmbH
+// author: Max Kellermann <[email protected]>
+
+#pragma once
+
+#include <stdexcept>
+
+/**
+ * Some operation has timed out (e.g. connecting to a server, waiting
+ * for reply from a server).
+ */
+class TimeoutError : public std::runtime_error {
+public:
+	using std::runtime_error::runtime_error;
+
+	TimeoutError() noexcept
+		:std::runtime_error("Timeout") {}
+};