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.

1 files changed, 5 insertions, 0 deletions

diff --git a/demux/demux.h b/demux/demux.h
index cd897be7e2..1d0038a5b0 100644
--- a/demux/demux.h
+++ b/demux/demux.h
@@ -192,6 +192,11 @@ typedef struct demuxer {
     //   monotonically increasing
     // - seeking leaves packet positions invariant
     bool allow_refresh_seeks;
+    // The file data was fully read, and there is no need to keep the stream
+    // open, keep the cache active, or to run the demuxer thread. Generating
+    // packets is not slow either (unlike e.g. libavdevice pseudo-demuxers).
+    // Typical examples: text subtitles, playlists
+    bool fully_read;
 
     // Bitmask of DEMUX_EVENT_*
     int events;