stream_libarchive: remove base filename stuff

Apparently this was so that when playing a video file from a .rar file,
it would load external subtitles with the same name (instead of looking
for mpv's rar:// mangled URL). This was requested on github almost 5
years ago. Seems like a shit feature, and why should I give a fuck? Drop
it, because it complicates some in progress change.

demux/demux.c

@@ -222,8 +222,6 @@ struct demux_internal {
     int64_t last_speed_query;
     uint64_t bytes_per_second;
     int64_t next_cache_update;
-    // Updated during init only.
-    char *stream_base_filename;
 
     // -- Access from demuxer thread only
     bool enable_recording;
@@ -2244,16 +2242,6 @@ void demux_update(demuxer_t *demuxer)
     pthread_mutex_unlock(&in->lock);
 }
 
-static void demux_init_cache(struct demuxer *demuxer)
-{
-    struct demux_internal *in = demuxer->in;
-    struct stream *stream = demuxer->stream;
-
-    char *base = NULL;
-    stream_control(stream, STREAM_CTRL_GET_BASE_FILENAME, &base);
-    in->stream_base_filename = talloc_steal(demuxer, base);
-}
-
 static void demux_init_cuesheet(struct demuxer *demuxer)
 {
     char *cue = mp_tags_get_str(demuxer->metadata, "cuesheet");
@@ -2417,7 +2405,6 @@ static struct demuxer *open_given_type(struct mpv_global *global,
             in->d_thread->partially_seekable = true;
         }
         demux_init_cuesheet(in->d_thread);
-        demux_init_cache(demuxer);
         demux_init_ccs(demuxer, opts);
         demux_copy(in->d_user, in->d_thread);
         in->duration = in->d_thread->duration;
@@ -3137,11 +3124,6 @@ static int cached_stream_control(struct demux_internal *in, int cmd, void *arg)
             return STREAM_UNSUPPORTED;
         *(int64_t *)arg = in->stream_size;
         return STREAM_OK;
-    case STREAM_CTRL_GET_BASE_FILENAME:
-        if (!in->stream_base_filename)
-            return STREAM_UNSUPPORTED;
-        *(char **)arg = talloc_strdup(NULL, in->stream_base_filename);
-        return STREAM_OK;
     }
     return STREAM_ERROR;
 }

player/loadfile.c

@@ -816,14 +816,7 @@ void autoload_external_files(struct MPContext *mpctx, struct mp_cancel *cancel)
         return;
 
     void *tmp = talloc_new(NULL);
-    char *base_filename = mpctx->filename;
+    struct subfn *list = find_external_files(mpctx->global, mpctx->filename,
-    char *stream_filename = NULL;
-    if (mpctx->demuxer) {
-        if (demux_stream_control(mpctx->demuxer, STREAM_CTRL_GET_BASE_FILENAME,
-                                    &stream_filename) > 0)
-            base_filename = talloc_steal(tmp, stream_filename);
-    }
-    struct subfn *list = find_external_files(mpctx->global, base_filename,
                                              mpctx->opts);
     talloc_steal(tmp, list);
 

stream/stream.h

@@ -54,9 +54,6 @@ enum stream_ctrl {
     // stream_memory.c
     STREAM_CTRL_SET_CONTENTS,
 
-    // stream_libarchive.c
-    STREAM_CTRL_GET_BASE_FILENAME,
-
     // Certain network protocols
     STREAM_CTRL_AVSEEK,
     STREAM_CTRL_HAS_AVSEEK,

stream/stream_libarchive.c

@@ -460,9 +460,6 @@ static int archive_entry_control(stream_t *s, int cmd, void *arg)
 {
     struct priv *p = s->priv;
     switch (cmd) {
-    case STREAM_CTRL_GET_BASE_FILENAME:
-        *(char **)arg = talloc_strdup(NULL, p->src->url);
-        return STREAM_OK;
     case STREAM_CTRL_GET_SIZE:
         if (p->entry_size < 0)
             break;