lib/upnp/Discovery: use DeferredMonitor instead of BlockingCall()

src/lib/upnp/Discovery.cxx

@@ -22,7 +22,6 @@
 #include "ContentDirectoryService.hxx"
 #include "Log.hxx"
 #include "lib/curl/Global.hxx"
-#include "event/Call.hxx"
 #include "util/DeleteDisposer.hxx"
 #include "util/ScopeExit.hxx"
 #include "util/RuntimeError.hxx"
@@ -34,7 +33,7 @@
 
 UPnPDeviceDirectory::Downloader::Downloader(UPnPDeviceDirectory &_parent,
 					    const Upnp_Discovery &disco)
-	:parent(_parent),
+	:DeferredMonitor(_parent.GetEventLoop()), parent(_parent),
 	 id(disco.DeviceId), url(disco.Location),
 	 expires(std::chrono::seconds(disco.Expires)),
 	 request(*parent.curl, url.c_str(), *this)
@@ -43,20 +42,16 @@ UPnPDeviceDirectory::Downloader::Downloader(UPnPDeviceDirectory &_parent,
 }
 
 void
-UPnPDeviceDirectory::Downloader::Start()
+UPnPDeviceDirectory::Downloader::Destroy()
 {
-	auto &event_loop = parent.GetEventLoop();
-
-	BlockingCall(event_loop, [this](){
-			request.Start();
-		});
+	parent.downloaders.erase_and_dispose(parent.downloaders.iterator_to(*this),
+					     DeleteDisposer());
 }
 
 void
-UPnPDeviceDirectory::Downloader::Destroy()
+UPnPDeviceDirectory::Downloader::RunDeferred()
 {
-	parent.downloaders.erase_and_dispose(parent.downloaders.iterator_to(*this),
-					     DeleteDisposer());
+	request.Start();
 }
 
 void

src/lib/upnp/Discovery.hxx

@@ -26,6 +26,7 @@
 #include "lib/curl/Handler.hxx"
 #include "lib/curl/Request.hxx"
 #include "thread/Mutex.hxx"
+#include "event/DeferredMonitor.hxx"
 #include "Compiler.h"
 
 #include <upnp/upnp.h>
@@ -83,7 +84,7 @@ class UPnPDeviceDirectory final : UpnpCallback {
 
 	class Downloader final
 		: public boost::intrusive::list_base_hook<boost::intrusive::link_mode<boost::intrusive::normal_link>>,
-		CurlResponseHandler {
+		DeferredMonitor, CurlResponseHandler {
 
 		UPnPDeviceDirectory &parent;
 
@@ -99,10 +100,16 @@ class UPnPDeviceDirectory final : UpnpCallback {
 		Downloader(UPnPDeviceDirectory &_parent,
 			   const Upnp_Discovery &disco);
 
-		void Start();
+		void Start() {
+			DeferredMonitor::Schedule();
+		}
+
 		void Destroy();
 
 	private:
+		/* virtual methods from DeferredMonitor */
+		void RunDeferred() override;
+
 		/* virtual methods from CurlResponseHandler */
 		void OnHeaders(unsigned status,
 			       std::multimap<std::string, std::string> &&headers) override;