Cleanup

No functional change.

nncmpp.c

@@ -82,6 +82,9 @@ enum
 
 // ncurses is notoriously retarded for input handling, we need something
 // different if only to receive mouse events reliably.
+//
+// 2020 update: ncurses is mostly reliable now but rxvt-unicode needs to start
+// supporting 1006, or ncurses needs to start supporting the 1015 mode.
 
 #include "termo.h"
 
@@ -609,7 +612,7 @@ static struct app_context
 	struct str_map playback_info;       ///< Current song info
 
 	struct poller_timer elapsed_event;  ///< Seconds elapsed event
-	int64_t elapsed_since;              ///< Time of the last tick
+	int64_t elapsed_since;              ///< Last tick ts or last elapsed time
 	bool elapsed_poll;                  ///< Poll MPD for the elapsed time?
 
 	// TODO: initialize these to -1
@@ -716,7 +719,7 @@ static struct config_schema g_config_settings[] =
 	  .comment   = "Whether to actively poll MPD for the elapsed time",
 	  .type      = CONFIG_ITEM_BOOLEAN,
 	  .on_change = on_poll_elapsed_time_changed,
-	  .default_  = "off" },
+	  .default_  = "on" },
 	{}
 };
 
@@ -3360,6 +3363,7 @@ mpd_read_time (const char *value, int *sec, int *optional_msec)
 		unsigned long n = strtoul (period + 1, &end, 10);
 		if (*end)
 			return;
+		// XXX: this relies on three decimal places
 		*optional_msec = MIN (INT_MAX, n);
 	}
 	unsigned long n = strtoul (value, &end, 10);
@@ -3383,6 +3387,33 @@ mpd_update_playlist_time (void)
 	}
 }
 
+static void
+mpd_set_elapsed_timer (int msec_past_second)
+{
+	int delay_msec = 1000 - msec_past_second;  // Until the next round second
+	if (!g.elapsed_poll)
+	{
+		poller_timer_set (&g.elapsed_event, delay_msec);
+		// Remember when the last round second was, relative to monotonic time
+		g.elapsed_since = clock_msec (CLOCK_BEST) - msec_past_second;
+		return;
+	}
+
+	// We may receive an earlier time, this seems to compensate for it well
+	// (I haven't seen it trigger more than 50ms too early)
+	delay_msec += 100;
+
+	// When playback stalls, avoid busy looping with the server
+	int elapsed_msec = g.song_elapsed * 1000 + msec_past_second;
+	if (elapsed_msec == g.elapsed_since)
+		delay_msec = MAX (delay_msec, 500);
+
+	// In polling mode, we're interested in progress rather than stability.
+	// We can reuse both the poller_timer struct and the timestamp field.
+	poller_timer_set (&g.elapsed_event, delay_msec);
+	g.elapsed_since = elapsed_msec;
+}
+
 static void
 mpd_update_playback_state (void)
 {
@@ -3421,20 +3452,9 @@ mpd_update_playback_state (void)
 
 	poller_timer_reset (&g.elapsed_event);
 	if (g.state == PLAYER_PLAYING)
-	{
-		int until_next = 1000 - msec_past_second;
-
-		// We could make use of "until_next", however this might create
-		// an intensive busy loop when playback stalls (typically because of
-		// some network issues).  Half a second will work reasonably well.
-		if (g.elapsed_poll)
-			until_next = 500;
-
-		// Set a timer for when the next round second of playback happens
-		poller_timer_set (&g.elapsed_event, until_next);
-		// Remember when the last round second was, relative to monotonic time
-		g.elapsed_since = clock_msec (CLOCK_BEST) - msec_past_second;
-	}
+		mpd_set_elapsed_timer (msec_past_second);
+	else
+		g.elapsed_since = -1;
 
 	// The server sends -1 when nothing is being played right now
 	unsigned long n;