[Summary] Fixed error with draining IOChannel in CrossthreadChannel on Windows.

Used IOChannel for base_ui on Windows instead of workaround which used to be working instead.

[Reviewed by] Paul Davis

libs/pbd/base_ui.cc

@@ -51,15 +51,10 @@ BaseUI::BaseUI (const string& str)
 	: m_context(MainContext::get_default())
 	, run_loop_thread (0)
 	, _name (str)
-#ifndef PLATFORM_WINDOWS
 	, request_channel (true)
-#endif
 {
 	base_ui_instance = this;
-
-#ifndef PLATFORM_WINDOWS
 	request_channel.set_receive_handler (sigc::mem_fun (*this, &BaseUI::request_handler));
-#endif
 
 	/* derived class must set _ok */
 }
@@ -124,24 +119,6 @@ BaseUI::quit ()
 	}
 }
 
-#ifdef PLATFORM_WINDOWS
-gboolean
-BaseUI::_request_handler (gpointer data)
-{
-	BaseUI* ui = static_cast<BaseUI*>(data);
-	return ui->request_handler ();
-}
-
-bool
-BaseUI::request_handler ()
-{
-	DEBUG_TRACE (DEBUG::EventLoop, "BaseUI::request_handler\n");
-	handle_ui_requests ();
-	// keep calling indefinitely at the timeout interval
-	return true;
-}
-
-#else
 bool
 BaseUI::request_handler (Glib::IOCondition ioc)
 {
@@ -166,17 +143,12 @@ BaseUI::request_handler (Glib::IOCondition ioc)
 
 	return true;
 }
-#endif
 
 void
 BaseUI::signal_new_request ()
 {
 	DEBUG_TRACE (DEBUG::EventLoop, "BaseUI::signal_new_request\n");
-#ifdef PLATFORM_WINDOWS
-	// handled in timeout, how to signal...?
-#else
 	request_channel.wakeup ();
-#endif
 }
 
 /**
@@ -186,11 +158,5 @@ void
 BaseUI::attach_request_source ()
 {
 	DEBUG_TRACE (DEBUG::EventLoop, "BaseUI::attach_request_source\n");
-#ifdef PLATFORM_WINDOWS
-	GSource* request_source = g_timeout_source_new(200);
-	g_source_set_callback (request_source, &BaseUI::_request_handler, this, NULL);
-	g_source_attach (request_source, m_context->gobj());
-#else
 	request_channel.attach (m_context);
-#endif
 }

libs/pbd/crossthread.win.cc

@@ -38,7 +38,7 @@ CrossThreadChannel::CrossThreadChannel (bool non_blocking)
 	// Create Send Socket
     send_socket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
     send_address.sin_family = AF_INET;
-    send_address.sin_addr.s_addr = INADDR_ANY;
+    send_address.sin_addr.s_addr = inet_addr("127.0.0.1");
     send_address.sin_port = htons(0);
     int status = bind(send_socket, (SOCKADDR*)&send_address,   
                   sizeof(send_address));
@@ -70,14 +70,7 @@ CrossThreadChannel::CrossThreadChannel (bool non_blocking)
         return;
 	}
 
-	// make the socket non-blockable if required
+	// recieve socket will be made non-blocking by GSource which will use it
-	mode = (u_long)non_blocking;
-	otp_result = 0;
-	
-	otp_result = ioctlsocket(receive_socket, FIONBIO, &mode);
-	if (otp_result != NO_ERROR) {
-		std::cerr << "CrossThreadChannel::CrossThreadChannel() Receive socket cannot be set to non blocking mode with error: " << WSAGetLastError() << std::endl;
-	}
 
 	// get assigned port number for Receive Socket
 	int recv_addr_len = sizeof(recv_address);
@@ -91,18 +84,15 @@ CrossThreadChannel::CrossThreadChannel (bool non_blocking)
 	// construct IOChannel
 	receive_channel = g_io_channel_win32_new_socket((gint)receive_socket);
 	
-	int flags = G_IO_FLAG_APPEND;
+	// set binary data type
-	if (non_blocking) {
+	GIOStatus g_status = g_io_channel_set_encoding (receive_channel, NULL, NULL);
-		flags |= G_IO_FLAG_NONBLOCK;
-	}
-	
-	GIOStatus g_status = g_io_channel_set_flags(receive_channel, (GIOFlags)flags,
-                           NULL);
-
 	if (G_IO_STATUS_NORMAL != g_status ) {
-		std::cerr << "CrossThreadChannel::CrossThreadChannel() Cannot set IOChannel flags " << std::endl;
+		std::cerr << "CrossThreadChannel::CrossThreadChannel() Cannot set flag for IOChannel. " << g_status << std::endl;
 		return;
 	}
+
+	// disable channel buffering
+	g_io_channel_set_buffered (receive_channel, false);
 }
 
 CrossThreadChannel::~CrossThreadChannel ()
@@ -132,11 +122,28 @@ CrossThreadChannel::drain ()
 {
 	/* flush the buffer - empty the channel from all requests */
 	GError *g_error = 0;
-	gchar* buffer;
+	gchar buffer[512];
 	gsize read = 0;
 
-	g_io_channel_read_to_end (receive_channel, &buffer, &read, &g_error);
+	while (1) {
-	g_free(buffer);
+		GIOStatus g_status = g_io_channel_read_chars (receive_channel, buffer, sizeof(buffer), &read, &g_error);
+
+		if (G_IO_STATUS_AGAIN == g_status) {
+			break;
+		}
+
+		if (G_IO_STATUS_NORMAL != g_status) {
+			std::cerr << "CrossThreadChannel::CrossThreadChannel() Cannot drain from read buffer! " << g_status << std::endl;
+			
+			if (g_error) {
+				std::cerr << "Error is Domain: " << g_error->domain << " Code: " << g_error->code << std::endl;
+				g_clear_error(&g_error);
+			} else {
+				std::cerr << "No error provided\n";
+			}
+			break;
+		}
+	}
 }
 
 

libs/pbd/pbd/base_ui.h

@@ -93,14 +93,9 @@ class LIBPBD_API BaseUI : public sigc::trackable, public PBD::EventLoop
 
 	virtual void thread_init () {};
 
-#ifdef PLATFORM_WINDOWS
-	static gboolean _request_handler (gpointer);
-	bool request_handler ();
-#else
 	/** Called when there input ready on the request_channel
 	 */
 	bool request_handler (Glib::IOCondition);
-#endif
 
 	void signal_new_request ();
 	void attach_request_source ();
@@ -115,9 +110,7 @@ class LIBPBD_API BaseUI : public sigc::trackable, public PBD::EventLoop
 	std::string _name; 
 	BaseUI* base_ui_instance;
 
-#ifndef PLATFORM_WINDOWS
 	CrossThreadChannel request_channel;
-#endif
 
 	static uint64_t rt_bit;