[listener] Rename LISTENER_PLAYLIST to LISTENER_QUEUE

src/db.c

@@ -4006,7 +4006,7 @@ db_queue_get_version()
 }
 
 /*
- * Increments the version of the queue in the admin table and notifies listener of LISTENER_PLAYLIST
+ * Increments the version of the queue in the admin table and notifies listener of LISTENER_QUEUE
  * about the change.
  *
  * This function must be called after successfully modifying the queue table in order to send
@@ -4044,7 +4044,7 @@ queue_inc_version_and_notify()
 
   db_transaction_end();
 
-  listener_notify(LISTENER_PLAYLIST);
+  listener_notify(LISTENER_QUEUE);
 }
 
 void

src/listener.h

@@ -6,8 +6,8 @@ enum listener_event_type
 {
   /* The player has been started, stopped or seeked */
   LISTENER_PLAYER    = (1 << 0),
-  /* The current playlist has been modified */
+  /* The current playback queue has been modified */
-  LISTENER_PLAYLIST  = (1 << 1),
+  LISTENER_QUEUE     = (1 << 1),
   /* The volume has been changed */
   LISTENER_VOLUME    = (1 << 2),
   /* A speaker has been enabled or disabled */

src/mpd.c

@@ -596,7 +596,7 @@ mpd_command_idle(struct evbuffer *evbuf, int argc, char **argv, char **errmsg)
 	    }
 	  else if (0 == strcmp(argv[i], "playlist"))
 	    {
-	      client->events |= LISTENER_PLAYLIST;
+	      client->events |= LISTENER_QUEUE;
 	    }
 	  else if (0 == strcmp(argv[i], "mixer"))
 	    {
@@ -617,7 +617,7 @@ mpd_command_idle(struct evbuffer *evbuf, int argc, char **argv, char **errmsg)
 	}
     }
   else
-    client->events = LISTENER_PLAYER | LISTENER_PLAYLIST | LISTENER_VOLUME | LISTENER_SPEAKER | LISTENER_OPTIONS;
+    client->events = LISTENER_PLAYER | LISTENER_QUEUE | LISTENER_VOLUME | LISTENER_SPEAKER | LISTENER_OPTIONS;
 
   idle_clients = client;
 
@@ -4544,7 +4544,7 @@ mpd_notify_idle_client(struct idle_client *client, enum listener_event_type type
 	evbuffer_add(client->evbuffer, "changed: player\n", 16);
 	break;
 
-      case LISTENER_PLAYLIST:
+      case LISTENER_QUEUE:
 	evbuffer_add(client->evbuffer, "changed: playlist\n", 18);
 	break;
 
@@ -4871,7 +4871,7 @@ int mpd_init(void)
 #endif
 
   idle_clients = NULL;
-  listener_add(mpd_listener_cb, LISTENER_PLAYER | LISTENER_PLAYLIST | LISTENER_VOLUME | LISTENER_SPEAKER | LISTENER_OPTIONS);
+  listener_add(mpd_listener_cb, LISTENER_PLAYER | LISTENER_QUEUE | LISTENER_VOLUME | LISTENER_SPEAKER | LISTENER_OPTIONS);
 
   return 0;
 

src/player.c

@@ -27,10 +27,25 @@
  * - notify about playback status changes
  * - maintain the playback queue
  * 
- * The player thread should *never* be making operations that may block, since
+ * The player thread should never be making operations that may block, since
  * that could block callers requesting status (effectively making forked-daapd
- * unresponsive) and it could also starve the outputs.
+ * unresponsive) and it could also starve the outputs. In practice this rule is
+ * not always obeyed, for instance some outputs do their setup in ways that
+ * could block.
  *
+ *
+ * About metadata
+ * --------------
+ * The player gets metadata from library + inputs and passes it to the outputs
+ * and other clients (e.g. Remotes). Text metadata is handled differently than
+ * artwork. Here's how text works:
+ *
+ *  1. On playback start, the player will TODO
+ *  2. During playback, the input may signal new metadata by making a
+ *     input_write() with the INPUT_FLAG_METADATA flag. When the player read
+ *     reaches that data, the player will request the metadata from the input
+ *     with input_metadata_get().
+ *  3. If the new metadata is different than the TODO
  */
 
 #ifdef HAVE_CONFIG_H
@@ -2796,7 +2811,7 @@ playerqueue_clear_history(void *arg, int *retval)
 
   cur_plversion++; // TODO [db_queue] need to update db queue version
 
-  listener_notify(LISTENER_PLAYLIST);
+  listener_notify(LISTENER_QUEUE);
 
   *retval = 0;
   return COMMAND_END;