[rhythmbox] xfade: handle streams fully buffering before preroll finishes

[Jonathan Matthew <jmatthew src gnome org>]

commit 87aedc5a2b5db84e917192b413b977be641e152e
Author: Jonathan Matthew <jonathan d14n org>
Date:   Sat Dec 5 20:52:03 2020 +1000

    xfade: handle streams fully buffering before preroll finishes
    
    If the stream is already buffered when preroll finishes, waiting
    for buffering to finish after that won't get us anywhere.

 backends/gstreamer/rb-player-gst-xfade.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)
---
diff --git a/backends/gstreamer/rb-player-gst-xfade.c b/backends/gstreamer/rb-player-gst-xfade.c
index 98b4b1781..e73dc1838 100644
--- a/backends/gstreamer/rb-player-gst-xfade.c
+++ b/backends/gstreamer/rb-player-gst-xfade.c
@@ -361,6 +361,7 @@ typedef struct
        gboolean fading;
        gboolean starting_eos;
        gboolean use_buffering;
+       gboolean buffered;
 
        gulong adjust_probe_id;
        gulong block_probe_id;
@@ -1881,6 +1882,7 @@ rb_player_gst_xfade_bus_cb (GstBus *bus, GstMessage *message, RBPlayerGstXFade *
 
                if (progress >= 100) {
                        GError *error = NULL;
+                       stream->buffered = TRUE;
                        switch (stream->state) {
                        case PREROLLING:
                                rb_debug ("stream %s is buffered, now waiting", stream->uri);
@@ -1942,10 +1944,13 @@ rb_player_gst_xfade_bus_cb (GstBus *bus, GstMessage *message, RBPlayerGstXFade *
                                progress = 100;
                                break;
                        default:
-                               rb_debug ("stream buffering, stopping playback");
-                               unlink_and_block_stream (stream);
+                               if (stream->buffered) {
+                                       rb_debug ("stream buffering, stopping playback");
+                                       unlink_and_block_stream (stream);
+                               }
                                break;
                        }
+                       stream->buffered = FALSE;
                }
 
                _rb_player_emit_buffering (RB_PLAYER (player), stream->stream_data, progress);
@@ -2178,6 +2183,7 @@ create_stream (RBPlayerGstXFade *player, const char *uri, gpointer stream_data,
        stream->state = WAITING;
 
        stream->use_buffering = FALSE;
+       stream->buffered = FALSE;
        for (i = 0; i < G_N_ELEMENTS (stream_schemes); i++) {
                if (gst_uri_has_protocol (uri, stream_schemes[i])) {
                        stream->use_buffering = TRUE;
@@ -2578,7 +2584,7 @@ stream_src_blocked_cb (GstPad *pad, GstPadProbeInfo *info, RBXFadeStream *stream
        gst_query_unref (query);
        g_object_unref (src);
 
-       if (stream->use_buffering) {
+       if (stream->use_buffering && (stream->buffered == FALSE)) {
                rb_debug ("stream %s requires buffering", stream->uri);
                switch (stream->state) {
                case PREROLL_PLAY: