aacparse: Add function for the baseparse subclass to push buffers downstream

Also handle the case gracefully where the subclass decides to drop
the first buffers and has no caps set yet. It's still required to
have valid caps set when the first buffer should be passed downstream.

gst/aacparse/gstbaseparse.c

@@ -735,7 +735,6 @@ gst_base_parse_handle_and_push_buffer (GstBaseParse * parse,
     GstBaseParseClass * klass, GstBuffer * buffer)
 {
   GstFlowReturn ret;
-  GstClockTime last_stop = GST_CLOCK_TIME_NONE;
 
   if (parse->priv->discont) {
     GST_DEBUG_OBJECT (parse, "marking DISCONT");
@@ -749,6 +748,46 @@ gst_base_parse_handle_and_push_buffer (GstBaseParse * parse,
    *        keep track of timestamp and calculate everything possible
    *        if not set already */
 
+  /* First buffers are dropped, this means that the subclass needs more
+   * frames to decide on the format and queues them internally */
+  if (ret == GST_BASE_PARSE_FLOW_DROPPED && !GST_PAD_CAPS (parse->srcpad)) {
+    gst_buffer_unref (buffer);
+    return GST_FLOW_OK;
+  }
+
+  /* convert internal flow to OK and mark discont for the next buffer. */
+  if (ret == GST_BASE_PARSE_FLOW_DROPPED) {
+    parse->priv->discont = TRUE;
+    ret = GST_FLOW_OK;
+
+    gst_buffer_unref (buffer);
+
+    return ret;
+  } else if (ret != GST_FLOW_OK) {
+    return ret;
+  }
+
+  return gst_base_parse_push_buffer (parse, buffer);
+}
+
+/**
+ * gst_base_parse_push_buffer:
+ * @parse: #GstBaseParse.
+ * @buffer: #GstBuffer.
+ *
+ * Pushes the buffer downstream, sends any pending events and
+ * does some timestamp and segment handling.
+ *
+ * This must be called with srcpad STREAM_LOCK held.
+ *
+ * Returns: #GstFlowReturn
+ */
+GstFlowReturn
+gst_base_parse_push_buffer (GstBaseParse * parse, GstBuffer * buffer)
+{
+  GstFlowReturn ret = GST_FLOW_OK;
+  GstClockTime last_stop = GST_CLOCK_TIME_NONE;
+
   if (GST_BUFFER_TIMESTAMP_IS_VALID (buffer))
     last_stop = GST_BUFFER_TIMESTAMP (buffer);
   if (last_stop != GST_CLOCK_TIME_NONE && GST_BUFFER_DURATION_IS_VALID (buffer))
@@ -792,7 +831,6 @@ gst_base_parse_handle_and_push_buffer (GstBaseParse * parse,
 
   /* TODO: Add to seek table */
 
-  if (ret == GST_FLOW_OK) {
   if (GST_BUFFER_TIMESTAMP_IS_VALID (buffer) &&
       GST_CLOCK_TIME_IS_VALID (parse->segment.stop) &&
       GST_BUFFER_TIMESTAMP (buffer) > parse->segment.stop) {
@@ -812,19 +850,11 @@ gst_base_parse_handle_and_push_buffer (GstBaseParse * parse,
     GST_LOG_OBJECT (parse, "frame (%d bytes) pushed: %d",
         GST_BUFFER_SIZE (buffer), ret);
   }
-  } else {
-    gst_buffer_unref (buffer);
-  }
 
   /* Update current running segment position */
   if (ret == GST_FLOW_OK && last_stop != GST_CLOCK_TIME_NONE)
     gst_segment_set_last_stop (&parse->segment, GST_FORMAT_TIME, last_stop);
 
-  /* convert internal flow to OK and mark discont for the next buffer. */
-  if (ret == GST_BASE_PARSE_FLOW_DROPPED) {
-    parse->priv->discont = TRUE;
-    ret = GST_FLOW_OK;
-  }
   return ret;
 }
 

gst/aacparse/gstbaseparse.h

@@ -225,6 +225,9 @@ struct _GstBaseParseClass {
 GType           gst_base_parse_get_type         (void);
 
 
+GstFlowReturn gst_base_parse_push_buffer (GstBaseParse *parse,
+                                          GstBuffer *buffer);
+
 void gst_base_parse_set_duration (GstBaseParse *parse,
                                   GstFormat fmt,
                                   gint64 duration);