player: enable cache and demuxer thread for subtitles too

Includes some logic for not starting the demuxer thread for fully read
subtitles. (Well, the cache will still waste _lots_ of resources, and
the cache always has to be created, because we don't know whether it'll
be needed _before_ opening the file.)

See #1597.

2 files changed, 7 insertions, 3 deletions

diff --git a/player/loadfile.c b/player/loadfile.c
index aba8b6c7df..bbfff46fe2 100644
--- a/player/loadfile.c
+++ b/player/loadfile.c
@@ -291,8 +291,8 @@ static void enable_demux_thread(struct MPContext *mpctx)
         demux_start_thread(mpctx->demuxer);
         for (int n = 0; n < mpctx->num_tracks; n++) {
             struct track *track = mpctx->tracks[n];
-            if (track->is_external && track->stream &&
-                track->stream->type != STREAM_SUB)
+            if (track->is_external && track->stream && !track->preloaded &&
+                !track->demuxer->fully_read)
             {
                 demux_set_wakeup_cb(track->demuxer, wakeup_demux, mpctx);
                 demux_start_thread(track->demuxer);
@@ -689,6 +689,7 @@ struct track *mp_add_external_file(struct MPContext *mpctx, char *filename,
     struct stream *stream = stream_open(filename, mpctx->global);
     if (!stream)
         goto err_out;
+    stream_enable_cache(&stream, &opts->stream_cache);
 
     char *demuxer_name = NULL;
     switch (filter) {
@@ -697,7 +698,6 @@ struct track *mp_add_external_file(struct MPContext *mpctx, char *filename,
         break;
     case STREAM_AUDIO:
         demuxer_name = opts->audio_demuxer_name;
-        stream_enable_cache(&stream, &opts->stream_cache);
         break;
     }
 
@@ -731,6 +731,8 @@ struct track *mp_add_external_file(struct MPContext *mpctx, char *filename,
     }
 
     MP_TARRAY_APPEND(NULL, mpctx->sources, mpctx->num_sources, demuxer);
+    if (mpctx->playback_initialized)
+        enable_demux_thread(mpctx);
     return first;
 
 err_out:
diff --git a/player/sub.c b/player/sub.c
index 16affc4448..f4c9e7822b 100644
--- a/player/sub.c
+++ b/player/sub.c
@@ -321,6 +321,8 @@ static void reinit_subdec(struct MPContext *mpctx, struct track *track,
     if (!track->preloaded && track->is_external && !opts->sub_clear_on_seek) {
         demux_seek(track->demuxer, 0, SEEK_ABSOLUTE);
         track->preloaded = sub_read_all_packets(dec_sub, track->stream);
+        if (track->preloaded)
+            demux_stop_thread(track->demuxer);
     }
 }