core: add demux_sub pseudo demuxer

Subtitle files are opened in mplayer.c, not using the demuxer
infrastructure in general. Pretend that this is not the case (outside of
the loading code) by opening a pseudo demuxer that does nothing. One
advantage is that the initialization code is now the same, and there's
no confusion about what the difference between track->stream,
track->sh_sub and mpctx->sh_sub is supposed to be.

This is a bit stupid, and it would be much better if there were proper
subtitle demuxers (there are many in recent FFmpeg, but not Libav). So
for now this is just a transition to a more proper architecture. Look
at demux_sub like an artifical limb: it's ugly, but don't hate it - it
helps you to get on with your life.

2 files changed, 5 insertions, 30 deletions

diff --git a/sub/dec_sub.h b/sub/dec_sub.h
index 263df19bc0..4eb833c52b 100644
--- a/sub/dec_sub.h
+++ b/sub/dec_sub.h
@@ -21,9 +21,6 @@ void sub_reset(struct sh_sub *sh, struct osd_state *osd);
 void sub_switchoff(struct sh_sub *sh, struct osd_state *osd);
 void sub_uninit(struct sh_sub *sh);
 
-struct sh_sub *sd_ass_create_from_track(struct ass_track *track,
-                                        const char *codec, struct MPOpts *opts);
-
 #ifdef CONFIG_ASS
 struct ass_track *sub_get_ass_track(struct osd_state *osd);
 #endif
diff --git a/sub/sd_ass.c b/sub/sd_ass.c
index 02d0ed15bf..b107e0438f 100644
--- a/sub/sd_ass.c
+++ b/sub/sd_ass.c
@@ -79,7 +79,9 @@ static int init(struct sh_sub *sh, struct osd_state *osd)
     } else {
         ctx = talloc_zero(NULL, struct sd_ass_priv);
         sh->context = ctx;
-        if (ass) {
+        if (sh->track) {
+            ctx->ass_track = sh->track;
+        } else if (ass) {
             ctx->ass_track = ass_new_track(osd->ass_library);
             if (sh->extradata)
                 ass_process_codec_private(ctx->ass_track, sh->extradata,
@@ -277,7 +279,8 @@ static void uninit(struct sh_sub *sh)
 {
     struct sd_ass_priv *ctx = sh->context;
 
-    ass_free_track(ctx->ass_track);
+    if (sh->track != ctx->ass_track)
+        ass_free_track(ctx->ass_track);
     talloc_free(ctx);
 }
 
@@ -293,31 +296,6 @@ const struct sd_functions sd_ass = {
     .uninit = uninit,
 };
 
-static int sd_ass_track_destructor(void *ptr)
-{
-    uninit(ptr);
-    return 1;
-}
-
-struct sh_sub *sd_ass_create_from_track(struct ass_track *track,
-                                        const char *codec, struct MPOpts *opts)
-{
-    struct sh_sub *sh = talloc(NULL, struct sh_sub);
-    talloc_set_destructor(sh, sd_ass_track_destructor);
-    *sh = (struct sh_sub) {
-        .opts = opts,
-        .gsh = talloc_struct(sh, struct sh_stream, {
-            .codec = codec,
-        }),
-        .context = talloc_struct(sh, struct sd_ass_priv, {
-            .ass_track = track,
-            .vsfilter_aspect = is_ass_sub(codec),
-        }),
-        .initialized = true,
-    };
-    return sh;
-}
-
 struct ass_track *sub_get_ass_track(struct osd_state *osd)
 {
     struct sh_sub *sh = osd ? osd->sh_sub : NULL;