[vlc-devel] [PATCH] lib: media_track: don't return an empty list

[Thomas Guillem]

This was done to make the distinction between errors (NULL) and 0 tracks (empty
list). Making this distinction is quite useless, specially since only alloc
errors can occur.
---
 include/vlc/libvlc_media.h        |  6 +++---
 include/vlc/libvlc_media_player.h |  6 +++---
 lib/media_track.c                 | 14 +++++++++-----
 test/libvlc/media.c               |  3 ++-
 4 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/include/vlc/libvlc_media.h b/include/vlc/libvlc_media.h
index d7ae42bb058..cc953c33f57 100644
--- a/include/vlc/libvlc_media.h
+++ b/include/vlc/libvlc_media.h
@@ -677,9 +677,9 @@ unsigned libvlc_media_tracks_get( libvlc_media_t *p_md,
  * \param p_md media descriptor object
  * \param type type of the track list to request
  *
- * \return a valid libvlc_media_tracklist_t or NULL in case of error, if there
- * is no track for a category, the returned list will have a size of 0, delete
- * with libvlc_media_tracklist_delete()
+ * \return a valid libvlc_media_tracklist_t or NULL if there is no tracks for
+ * that category, or in case of error, delete with
+ * libvlc_media_tracklist_delete()
  */
 LIBVLC_API libvlc_media_tracklist_t *
 libvlc_media_get_tracklist( libvlc_media_t *p_md, libvlc_track_type_t type );
diff --git a/include/vlc/libvlc_media_player.h b/include/vlc/libvlc_media_player.h
index e861cd5fca7..a67d243426d 100644
--- a/include/vlc/libvlc_media_player.h
+++ b/include/vlc/libvlc_media_player.h
@@ -1304,9 +1304,9 @@ LIBVLC_API void libvlc_media_player_set_video_title_display( libvlc_media_player
  * \param p_mi the media player
  * \param type type of the track list to request
  *
- * \return a valid libvlc_media_tracklist_t or NULL in case of error, if there
- * is no track for a category, the returned list will have a size of 0, delete
- * with libvlc_media_tracklist_delete()
+ * \return a valid libvlc_media_tracklist_t or NULL if there is no tracks for
+ * that category, or in case of error, delete with
+ * libvlc_media_tracklist_delete()
  */
 LIBVLC_API libvlc_media_tracklist_t *
 libvlc_media_player_get_tracklist( libvlc_media_player_t *p_mi,
diff --git a/lib/media_track.c b/lib/media_track.c
index a11c2973c65..76ad34e31d3 100644
--- a/lib/media_track.c
+++ b/lib/media_track.c
@@ -199,10 +199,12 @@ libvlc_media_tracklist_from_es_array( es_format_t **es_array,
             count++;
     }
 
-    libvlc_media_tracklist_t *list = libvlc_media_tracklist_alloc( count );
+    if( count == 0 )
+        return NULL;
 
-    if( count == 0 || list == NULL )
-        return list;
+    libvlc_media_tracklist_t *list = libvlc_media_tracklist_alloc( count );
+    if( list == NULL )
+        return NULL;
 
     for( size_t i = 0; i < es_count; ++i )
     {
@@ -253,9 +255,11 @@ libvlc_media_tracklist_from_player( vlc_player_t *player,
     const enum es_format_category_e cat = libvlc_track_type_to_escat( type );
 
     size_t count = vlc_player_GetTrackCount( player, cat );
-    libvlc_media_tracklist_t *list = libvlc_media_tracklist_alloc( count );
+    if( count == 0 )
+        return NULL;
 
-    if( count == 0 || list == NULL )
+    libvlc_media_tracklist_t *list = libvlc_media_tracklist_alloc( count );
+    if( list == NULL )
         return NULL;
 
     for( size_t i = 0; i < count; ++i )
diff --git a/test/libvlc/media.c b/test/libvlc/media.c
index 65673c855ff..4442dd36422 100644
--- a/test/libvlc/media.c
+++ b/test/libvlc/media.c
@@ -51,7 +51,8 @@ static void print_media(libvlc_media_t *media)
         const libvlc_track_type_t type = types[i];
         libvlc_media_tracklist_t *tracklist =
             libvlc_media_get_tracklist(media, type);
-        assert(tracklist);
+        if (tracklist == NULL)
+            continue;
 
         for (size_t j = 0; j < libvlc_media_tracklist_count(tracklist); ++j)
         {
-- 
2.20.1