media library/tag editor: block idle while doing hierarchical searches

idle should be blocked in such cases since it would be enabled and
disabled a few times by each mpd command, which makes no sense and
slows down the whole process.

src/media_library.cpp

@@ -201,6 +201,10 @@ void MediaLibrary::Update()
 	
 	if (!hasTwoColumns && !Artists->Empty() && Albums->Empty() && Songs->Empty())
 	{
+		// idle has to be blocked for now since it would be enabled and
+		// disabled a few times by each mpd command, which makes no sense
+		// and slows down the whole process.
+		Mpd.BlockIdle(1);
 		Albums->Reset();
 		MPD::TagList list;
 		locale_to_utf(Artists->Current());
@@ -239,6 +243,7 @@ void MediaLibrary::Update()
 			Albums->AddOption(SearchConstraints("", AllTracksMarker));
 		}
 		Albums->Refresh();
+		Mpd.BlockIdle(0);
 	}
 	else if (hasTwoColumns && Albums->Empty())
 	{
@@ -246,6 +251,7 @@ void MediaLibrary::Update()
 		MPD::TagList artists;
 		*Albums << XY(0, 0) << "Fetching albums...";
 		Albums->Window::Refresh();
+		Mpd.BlockIdle(1);
 		Mpd.GetList(artists, Config.media_lib_primary_tag);
 		for (MPD::TagList::iterator i = artists.begin(); i != artists.end(); ++i)
 		{
@@ -289,6 +295,7 @@ void MediaLibrary::Update()
 				}
 			}
 		}
+		Mpd.BlockIdle(0);
 		if (!Albums->Empty())
 			Albums->Sort<SearchConstraintsSorting>();
 		Albums->Refresh();

src/mpdpp.cpp

@@ -142,18 +142,21 @@ void MPD::Connection::SetErrorHandler(ErrorHandler handler, void *data)
 
 void MPD::Connection::GoIdle()
 {
-	if (supportsIdle && !isIdle && mpd_send_idle(itsConnection))
+	if (supportsIdle && !itsIdleBlocked && !isIdle && mpd_send_idle(itsConnection))
 		isIdle = 1;
 }
 
 int MPD::Connection::GoBusy()
 {
+	int flags = 0;
 	if (isIdle && mpd_send_noidle(itsConnection))
 	{
 		isIdle = 0;
-		return mpd_recv_idle(itsConnection, 1);
+		if (hasData)
+			flags = mpd_recv_idle(itsConnection, 1);
+		mpd_response_finish(itsConnection);
 	}
-	return 0;
+	return flags;
 }
 
 void MPD::Connection::UpdateStatus()

src/mpdpp.h

@@ -95,6 +95,7 @@ namespace MPD
 			unsigned Version() const;
 			
 			void SetIdleEnabled(bool val) { isIdleEnabled = val; }
+			void BlockIdle(bool val) { itsIdleBlocked = val; }
 			bool SupportsIdle() const { return supportsIdle; }
 			void OrderDataFetching() { hasData = 1; }
 			int GetFD() const { return itsFD; }
@@ -227,6 +228,7 @@ namespace MPD
 			int itsFD;
 			bool isIdle;
 			bool isIdleEnabled;
+			bool itsIdleBlocked;
 			bool supportsIdle;
 			bool hasData;
 			

src/tag_editor.cpp

@@ -232,6 +232,7 @@ void TagEditor::Update()
 		{
 			*Albums << XY(0, 0) << "Fetching albums...";
 			Albums->Window::Refresh();
+			Mpd.BlockIdle(1); // for the same reason as in media library
 			Mpd.GetList(list, MPD_TAG_ALBUM);
 			for (MPD::TagList::const_iterator it = list.begin(); it != list.end(); ++it)
 			{
@@ -246,6 +247,7 @@ void TagEditor::Update()
 				}
 				MPD::FreeSongList(l);
 			}
+			Mpd.BlockIdle(0);
 			Albums->Sort<CaseInsensitiveSorting>();
 		}
 		else