From bfd03537f0971271583f85183136aafedad60794 Mon Sep 17 00:00:00 2001
From: Matthew Waters <matthew@centricular.com>
Date: Tue, 2 Jun 2020 17:35:00 +1000
Subject: [PATCH] ccconverter: also copy buffer metadata when draining

Fixes buffers without PTS/DTS/meta/etc when receiving an EOS with data
still stored in the internal scratch buffer.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1318>
---
 ext/closedcaption/gstccconverter.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/ext/closedcaption/gstccconverter.c b/ext/closedcaption/gstccconverter.c
index 6db0490460..a9da170f93 100644
--- a/ext/closedcaption/gstccconverter.c
+++ b/ext/closedcaption/gstccconverter.c
@@ -2195,6 +2195,7 @@ reset_counters (GstCCConverter * self)
 static GstFlowReturn
 drain_input (GstCCConverter * self)
 {
+  GstBaseTransformClass *bclass = GST_BASE_TRANSFORM_GET_CLASS (self);
   GstBaseTransform *trans = GST_BASE_TRANSFORM (self);
   GstFlowReturn ret = GST_FLOW_OK;
 
@@ -2202,8 +2203,22 @@ drain_input (GstCCConverter * self)
       || self->scratch_cea608_2_len > 0 || can_generate_output (self)) {
     GstBuffer *outbuf;
 
+    if (!self->previous_buffer) {
+      GST_WARNING_OBJECT (self, "Attempt to draining without a previous "
+          "buffer.  Aborting");
+      return GST_FLOW_OK;
+    }
+
     outbuf = gst_buffer_new_allocate (NULL, MAX_CDP_PACKET_LEN, NULL);
 
+    if (bclass->copy_metadata) {
+      if (!bclass->copy_metadata (trans, self->previous_buffer, outbuf)) {
+        /* something failed, post a warning */
+        GST_ELEMENT_WARNING (self, STREAM, NOT_IMPLEMENTED,
+            ("could not copy metadata"), (NULL));
+      }
+    }
+
     ret = gst_cc_converter_transform (self, NULL, outbuf);
     if (gst_buffer_get_size (outbuf) <= 0) {
       /* try to move the output along */