lib/{curl,upnp}: add more exception handlers

Bugs found by Coverity.

src/lib/curl/Request.cxx

@@ -72,7 +72,7 @@ CurlRequest::~CurlRequest() noexcept
 }
 
 void
-CurlRequest::Start() noexcept
+CurlRequest::Start()
 {
 	assert(!registered);
 

src/lib/curl/Request.hxx

@@ -91,7 +91,7 @@ public:
 	 *
 	 * This method must be called in the event loop thread.
 	 */
-	void Start() noexcept;
+	void Start();
 
 	/**
 	 * Unregister this request via CurlGlobal::Remove().

src/lib/upnp/Discovery.cxx

@@ -174,15 +174,19 @@ UPnPDeviceDirectory::OnAlive(Upnp_Discovery *disco) noexcept
 {
 	if (isMSDevice(disco->DeviceType) ||
 	    isCDService(disco->ServiceType)) {
-		auto *downloader = new Downloader(*this, *disco);
-
 		try {
-			downloader->Start();
-		} catch (...) {
-			BlockingCall(GetEventLoop(), [downloader](){
-					downloader->Destroy();
-				});
+			auto *downloader = new Downloader(*this, *disco);
 
+			try {
+				downloader->Start();
+			} catch (...) {
+				BlockingCall(GetEventLoop(), [downloader](){
+						downloader->Destroy();
+					});
+
+				throw;
+			}
+		} catch (...) {
 			LogError(std::current_exception());
 			return UPNP_E_SUCCESS;
 		}
@@ -251,7 +255,7 @@ UPnPDeviceDirectory::ExpireDevices()
 
 UPnPDeviceDirectory::UPnPDeviceDirectory(EventLoop &event_loop,
 					 UpnpClient_Handle _handle,
-					 UPnPDiscoveryListener *_listener) noexcept
+					 UPnPDiscoveryListener *_listener)
 	:curl(event_loop), handle(_handle),
 	 listener(_listener)
 {

src/lib/upnp/Discovery.hxx

@@ -110,7 +110,11 @@ class UPnPDeviceDirectory final : UpnpCallback {
 
 	private:
 		void OnDeferredStart() noexcept {
-			request.Start();
+			try {
+				request.Start();
+			} catch (...) {
+				OnError(std::current_exception());
+			}
 		}
 
 		/* virtual methods from CurlResponseHandler */
@@ -147,7 +151,7 @@ class UPnPDeviceDirectory final : UpnpCallback {
 
 public:
 	UPnPDeviceDirectory(EventLoop &event_loop, UpnpClient_Handle _handle,
-			    UPnPDiscoveryListener *_listener=nullptr) noexcept;
+			    UPnPDiscoveryListener *_listener=nullptr);
 	~UPnPDeviceDirectory() noexcept;
 
 	UPnPDeviceDirectory(const UPnPDeviceDirectory &) = delete;

src/storage/plugins/CurlStorage.cxx

@@ -140,7 +140,11 @@ private:
 	void OnDeferredStart() noexcept {
 		assert(!done);
 
-		request.Start();
+		try {
+			request.Start();
+		} catch (...) {
+			OnError(std::current_exception());
+		}
 	}
 
 	/* virtual methods from CurlResponseHandler */