status: make idle events handling independent of the order of their arrival

src/actions.cpp

@@ -2681,7 +2681,7 @@ void seek()
 	Progressbar::lock();
 	Statusbar::lock();
 
-	unsigned songpos = Status::elapsedTime();
+	unsigned songpos = Status::get().elapsedTime();
 	auto t = Timer;
 	
 	int old_timeout = wFooter->getTimeout();

src/ncmpcpp.cpp

@@ -170,6 +170,7 @@ int main(int argc, char **argv)
 						throw MPD::ClientError(MPD_ERROR_STATE, "MPD < 0.16.0 is not supported", false);
 					}
 					wFooter->addFDCallback(Mpd.GetFD(), Statusbar::Helpers::mpd);
+					Status::clear(); // reset local status info
 					Status::update(-1); // we need info about new connection
 					
 					if (Config.jump_to_now_playing_song_at_start)
@@ -179,7 +180,9 @@ int main(int argc, char **argv)
 							myPlaylist->main().highlight(curr_pos);
 					}
 					
-					// Set TCP_NODELAY on the tcp socket as this significantly speeds up operations.
+					// Set TCP_NODELAY on the tcp socket as we are using write-write-read pattern
+					// a lot (idle - write, noidle - write, then read the result of noidle), which
+					// kills the performance.
 					int flag = 1;
 					setsockopt(Mpd.GetFD(), IPPROTO_TCP, TCP_NODELAY, &flag, sizeof(flag));
 

src/status.cpp

@@ -55,17 +55,18 @@ size_t playing_song_scroll_begin = 0;
 size_t first_line_scroll_begin = 0;
 size_t second_line_scroll_begin = 0;
 
+MPD::Status m_status;
+
+// local copies of these are needed to be independent
+// of the order of idle events incoming from MPD.
 char m_repeat = 0;
 char m_random = 0;
 char m_single = 0;
 char m_consume = 0;
 char m_crossfade = 0;
 char m_db_updating = 0;
-
-MPD::Status m_status;
-// needed for the way events are emitted in consume mode after song ends
 int m_current_song_id = 0;
-unsigned m_elapsed_time = 0;
+unsigned m_playlist_version = 0;
 
 void drawTitle(const MPD::Song &np)
 {
@@ -169,21 +170,23 @@ void Status::update(int event)
 {
 	MPD::Status old_status = m_status;
 	m_status = Mpd.getStatus();
-	m_elapsed_time = m_status.elapsedTime();
 	
 	if (event & MPD_IDLE_DATABASE)
 		Changes::database();
 	if (event & MPD_IDLE_STORED_PLAYLIST)
 		Changes::storedPlaylists();
 	if (event & MPD_IDLE_PLAYLIST)
-		Changes::playlist(old_status.empty() ? 0 : old_status.playlistVersion());
+	{
+		Changes::playlist(m_playlist_version);
+		m_playlist_version = m_status.playlistVersion();
+	}
 	if (event & MPD_IDLE_PLAYER)
 	{
 		Changes::playerState();
 		if (m_current_song_id != m_status.currentSongID())
 		{
-			m_current_song_id = m_status.currentSongID();
 			Changes::songID();
+			m_current_song_id = m_status.currentSongID();
 		}
 	}
 	if (event & MPD_IDLE_MIXER)
@@ -192,20 +195,21 @@ void Status::update(int event)
 		Changes::outputs();
 	if (event & (MPD_IDLE_UPDATE | MPD_IDLE_OPTIONS))
 	{
+		bool show_msg = !old_status.empty();
 		if (event & MPD_IDLE_UPDATE)
-			Changes::dbUpdateState(!old_status.empty());
+			Changes::dbUpdateState(show_msg);
 		if (event & MPD_IDLE_OPTIONS)
 		{
-			if (old_status.empty() || old_status.repeat() != m_status.repeat())
+			if (('r' == m_repeat) != m_status.repeat())
-				Changes::repeat(!old_status.empty());
+				Changes::repeat(show_msg);
-			if (old_status.empty() || old_status.random() != m_status.random())
+			if (('z' == m_random) != m_status.random())
-				Changes::random(!old_status.empty());
+				Changes::random(show_msg);
-			if (old_status.empty() || old_status.single() != m_status.single())
+			if (('s' == m_single) != m_status.single())
-				Changes::single(!old_status.empty());
+				Changes::single(show_msg);
-			if (old_status.empty() || old_status.consume() != m_status.consume())
+			if (('c' == m_consume) != m_status.consume())
-				Changes::consume(!old_status.empty());
+				Changes::consume(show_msg);
-			if (old_status.empty() || old_status.crossfade() != m_status.crossfade())
+			if (('x' == m_crossfade) != m_status.crossfade())
-				Changes::crossfade(!old_status.empty());
+				Changes::crossfade(show_msg);
 		}
 		Changes::flags();
 	}
@@ -217,18 +221,25 @@ void Status::update(int event)
 		applyToVisibleWindows(&BaseScreen::refreshWindow);
 }
 
-/*************************************************************************/
+void Status::clear()
+{
+	// reset local variables
+	m_status.clear();
+	m_repeat = 0;
+	m_random = 0;
+	m_single = 0;
+	m_consume = 0;
+	m_crossfade = 0;
+	m_db_updating = 0;
+	m_current_song_id = 0;
+	m_playlist_version = 0;
+}
 
 const MPD::Status &Status::get()
 {
 	return m_status;
 }
 
-unsigned Status::elapsedTime()
-{
-	return m_elapsed_time;
-}
-
 /*************************************************************************/
 
 void Status::Changes::playlist(unsigned previous_version)
@@ -388,7 +399,7 @@ void Status::Changes::songID()
 void Status::Changes::elapsedTime(bool update_elapsed)
 {
 	if (update_elapsed)
-		m_elapsed_time = Mpd.getStatus().elapsedTime();
+		m_status = Mpd.getStatus();
 	const auto &st = m_status;
 	
 	if (st.playerState() == MPD::psStop)
@@ -420,17 +431,17 @@ void Status::Changes::elapsedTime(bool update_elapsed)
 					if (Config.display_remaining_time)
 					{
 						tracklength += "-";
-						tracklength += MPD::Song::ShowTime(st.totalTime()-m_elapsed_time);
+						tracklength += MPD::Song::ShowTime(st.totalTime()-st.elapsedTime());
 					}
 					else
-						tracklength += MPD::Song::ShowTime(m_elapsed_time);
+						tracklength += MPD::Song::ShowTime(st.elapsedTime());
 					tracklength += "/";
 					tracklength += MPD::Song::ShowTime(st.totalTime());
 					tracklength += "]";
 				}
 				else
 				{
-					tracklength += MPD::Song::ShowTime(m_elapsed_time);
+					tracklength += MPD::Song::ShowTime(st.elapsedTime());
 					tracklength += "]";
 				}
 				NC::WBuffer np_song;
@@ -444,10 +455,10 @@ void Status::Changes::elapsedTime(bool update_elapsed)
 			if (Config.display_remaining_time)
 			{
 				tracklength = "-";
-				tracklength += MPD::Song::ShowTime(st.totalTime()-m_elapsed_time);
+				tracklength += MPD::Song::ShowTime(st.totalTime()-st.elapsedTime());
 			}
 			else
-				tracklength = MPD::Song::ShowTime(m_elapsed_time);
+				tracklength = MPD::Song::ShowTime(st.elapsedTime());
 			if (st.totalTime())
 			{
 				tracklength += "/";
@@ -487,7 +498,7 @@ void Status::Changes::elapsedTime(bool update_elapsed)
 			flags();
 	}
 	if (Progressbar::isUnlocked())
-		Progressbar::draw(m_elapsed_time, st.totalTime());
+		Progressbar::draw(st.elapsedTime(), st.totalTime());
 }
 
 void Status::Changes::repeat(bool show_msg)

src/status.h

@@ -32,9 +32,9 @@ void handleServerError(MPD::ServerError &e);
 void trace(bool update_timer, bool update_window_timeout);
 inline void trace() { trace(true, false); }
 void update(int event);
+void clear();
 
 const MPD::Status &get();
-unsigned elapsedTime();
 
 namespace Changes {//
 

src/statusbar.cpp

@@ -112,7 +112,7 @@ void Statusbar::unlock()
 				put() << wclrtoeol;
 				break;
 			case Design::Alternative:
-				Progressbar::draw(Status::elapsedTime(), Status::get().totalTime());
+				Progressbar::draw(Status::get().elapsedTime(), Status::get().totalTime());
 				break;
 		}
 		wFooter->refresh();
@@ -145,7 +145,7 @@ void Statusbar::tryRedraw()
 					Status::Changes::elapsedTime(false);
 					break;
 				case Design::Alternative:
-					Progressbar::draw(Status::elapsedTime(), Status::get().totalTime());
+					Progressbar::draw(Status::get().elapsedTime(), Status::get().totalTime());
 					break;
 			}
 			wFooter->refresh();