From cd25bc2b76be720e974b3b5aa4bf3d433081b163 Mon Sep 17 00:00:00 2001
From: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Date: Thu, 13 Oct 2011 09:57:02 -0300
Subject: [PATCH] Don't overwrite metadata when changing track

If we use the same hash table to set the new metadata, we have 2
undesired behaviors:

1) New track may contain fields from previous track if it didn't set all
the fields
2) If we fail on parsing the signal, we will still change some of the
fields
---
 audio/media.c     | 42 ++++++++++++++++++++++++++++--------------
 doc/media-api.txt |  6 ++++++
 2 files changed, 34 insertions(+), 14 deletions(-)

diff --git a/audio/media.c b/audio/media.c
index 5848fb513..eecb44da0 100644
--- a/audio/media.c
+++ b/audio/media.c
@@ -1366,6 +1366,7 @@ static gboolean parse_player_metadata(struct media_player *mp,
 {
 	DBusMessageIter dict;
 	DBusMessageIter var;
+	GHashTable *track;
 	int ctype;
 	gboolean title = FALSE;
 
@@ -1375,6 +1376,9 @@ static gboolean parse_player_metadata(struct media_player *mp,
 
 	dbus_message_iter_recurse(iter, &dict);
 
+	track = g_hash_table_new_full(g_direct_hash, g_direct_equal, NULL,
+							metadata_value_free);
+
 	while ((ctype = dbus_message_iter_get_arg_type(&dict)) !=
 							DBUS_TYPE_INVALID) {
 		DBusMessageIter entry;
@@ -1383,21 +1387,21 @@ static gboolean parse_player_metadata(struct media_player *mp,
 		int id;
 
 		if (ctype != DBUS_TYPE_DICT_ENTRY)
-			return FALSE;
+			goto parse_error;
 
 		dbus_message_iter_recurse(&dict, &entry);
 		if (dbus_message_iter_get_arg_type(&entry) != DBUS_TYPE_STRING)
-			return FALSE;
+			goto parse_error;
 
 		dbus_message_iter_get_basic(&entry, &key);
 		dbus_message_iter_next(&entry);
 
 		id = metadata_to_val(key);
 		if (id < 0)
-			return FALSE;
+			goto parse_error;
 
 		if (dbus_message_iter_get_arg_type(&entry) != DBUS_TYPE_VARIANT)
-			return FALSE;
+			goto parse_error;
 
 		dbus_message_iter_recurse(&entry, &var);
 
@@ -1412,7 +1416,7 @@ static gboolean parse_player_metadata(struct media_player *mp,
 		case AVRCP_MEDIA_ATTRIBUTE_GENRE:
 			if (value->type != DBUS_TYPE_STRING) {
 				g_free(value);
-				return FALSE;
+				goto parse_error;
 			}
 
 			dbus_message_iter_get_basic(&var, &value->value.str);
@@ -1422,13 +1426,13 @@ static gboolean parse_player_metadata(struct media_player *mp,
 		case AVRCP_MEDIA_ATTRIBUTE_DURATION:
 			if (value->type != DBUS_TYPE_UINT32) {
 				g_free(value);
-				return FALSE;
+				goto parse_error;
 			}
 
 			dbus_message_iter_get_basic(&var, &value->value.num);
 			break;
 		default:
-			return FALSE;
+			goto parse_error;
 		}
 
 		switch (value->type) {
@@ -1440,24 +1444,34 @@ static gboolean parse_player_metadata(struct media_player *mp,
 			DBG("%s=%u", key, value->value.num);
 		}
 
-		if (!mp->track)
-			mp->track = g_hash_table_new_full(g_direct_hash,
-							g_direct_equal, NULL,
-							metadata_value_free);
-
-		g_hash_table_replace(mp->track, GUINT_TO_POINTER(id), value);
+		g_hash_table_replace(track, GUINT_TO_POINTER(id), value);
 		dbus_message_iter_next(&dict);
 	}
 
 	if (title == FALSE)
-		return TRUE;
+		goto parse_error;
+
+	if (g_hash_table_size(track) == 0) {
+		g_hash_table_unref(track);
+		track = NULL;
+	}
 
+	if (mp->track != NULL)
+		g_hash_table_unref(mp->track);
+
+	mp->track = track;
 	mp->position = 0;
 	g_timer_start(mp->timer);
 
 	avrcp_player_event(mp->player, AVRCP_EVENT_TRACK_CHANGED, NULL);
 
 	return TRUE;
+
+parse_error:
+	if (track)
+		g_hash_table_unref(track);
+
+	return FALSE;
 }
 
 static gboolean track_changed(DBusConnection *connection, DBusMessage *msg,
diff --git a/doc/media-api.txt b/doc/media-api.txt
index 7dc766103..b8dcdbd23 100644
--- a/doc/media-api.txt
+++ b/doc/media-api.txt
@@ -144,6 +144,12 @@ Signals		PropertyChanged(string setting, variant value)
 
 		TrackChanged(dict metadata)
 
+			This signal indicates that current track has changed.
+			All available metadata for the new track shall be set
+			at once in the metadata argument. Metadata cannot be
+			updated in parts, otherwise it will be interpreted as
+			multiple track changes.
+
 			Possible values:
 
 				string Title:
-- 
2.47.3