player: add a number of new playlist contol commands/properties

Should give a good deal more explicit control and insight over the
player state.

Some feel a bit pointless, and/or expose internal weirdness. However,
it's not like the existing weirdness didn't exist before, or can be made
go away. (In part, the weirdness is because certain in-between states
are visible. Hiding them would make things simpler, but less flexible.)

Maybe this actually gives users a better idea how the API _should_ look
like, too.

On a side note, this tries to really guarantee that mpctx->playing is
set between playback start/end. For that, the loadfile.c changes assume
that mpctx->playing is set (guaranteed by code above the change), and
that playing->filename is set (probably could never be false; was broken
before and actually would have crashed if that could ever happen; in any
case, also add an assert to playlist.c for this).

playlist_entry_to_index() now tolerates playlist_entrys that are not
part of the playlist. This is also needed for mpctx->playing.

1 files changed, 2 insertions, 2 deletions

diff --git a/common/playlist.c b/common/playlist.c
index 1fd202b98f..89c644dc33 100644
--- a/common/playlist.c
+++ b/common/playlist.c
@@ -62,6 +62,7 @@ static void playlist_update_indexes(struct playlist *pl, int start, int end)
 
 void playlist_add(struct playlist *pl, struct playlist_entry *add)
 {
+    assert(add->filename);
     MP_TARRAY_APPEND(pl, pl->entries, pl->num_entries, add);
     add->pl = pl;
     add->pl_index = pl->num_entries - 1;
@@ -283,9 +284,8 @@ void playlist_append_entries(struct playlist *pl, struct playlist *source_pl)
 // Return -1 if e is not on the list, or if e is NULL.
 int playlist_entry_to_index(struct playlist *pl, struct playlist_entry *e)
 {
-    if (!e)
+    if (!e || e->pl != pl)
         return -1;
-    assert(e->pl == pl);
     return e->pl_index;
 }